Generating and repairing genetically programmed DNA breaks during immunoglobulin class switch recombination

Science.gov (United States)

Nicolas, Laura; Cols, Montserrat; Choi, Jee Eun; Chaudhuri, Jayanta; Vuong, Bao

2018-01-01

Adaptive immune responses require the generation of a diverse repertoire of immunoglobulins (Igs) that can recognize and neutralize a seemingly infinite number of antigens. V(D)J recombination creates the primary Ig repertoire, which subsequently is modified by somatic hypermutation (SHM) and class switch recombination (CSR). SHM promotes Ig affinity maturation whereas CSR alters the effector function of the Ig. Both SHM and CSR require activation-induced cytidine deaminase (AID) to produce dU:dG mismatches in the Ig locus that are transformed into untemplated mutations in variable coding segments during SHM or DNA double-strand breaks (DSBs) in switch regions during CSR. Within the Ig locus, DNA repair pathways are diverted from their canonical role in maintaining genomic integrity to permit AID-directed mutation and deletion of gene coding segments. Recently identified proteins, genes, and regulatory networks have provided new insights into the temporally and spatially coordinated molecular interactions that control the formation and repair of DSBs within the Ig locus. Unravelling the genetic program that allows B cells to selectively alter the Ig coding regions while protecting non-Ig genes from DNA damage advances our understanding of the molecular processes that maintain genomic integrity as well as humoral immunity. PMID:29744038

Component Repair Times Obtained from MSPI Data

Energy Technology Data Exchange (ETDEWEB)

Eide, Steven A. [Curtiss-Wright/Scietech, Ketchum, ID (United States); Cadwallader, Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-05-01

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

Semi-Automated Diagnosis, Repair, and Rework of Spacecraft Electronics

Science.gov (United States)

Struk, Peter M.; Oeftering, Richard C.; Easton, John W.; Anderson, Eric E.

2008-01-01

NASA's Constellation Program for Exploration of the Moon and Mars places human crews in extreme isolation in resource scarce environments. Near Earth, the discontinuation of Space Shuttle flights after 2010 will alter the up- and down-mass capacity for the International Space Station (ISS). NASA is considering new options for logistics support strategies for future missions. Aerospace systems are often composed of replaceable modular blocks that minimize the need for complex service operations in the field. Such a strategy however, implies a robust and responsive logistics infrastructure with relatively low transportation costs. The modular Orbital Replacement Units (ORU) used for ISS requires relatively large blocks of replacement hardware even though the actual failed component may really be three orders of magnitude smaller. The ability to perform in-situ repair of electronics circuits at the component level can dramatically reduce the scale of spares and related logistics cost. This ability also reduces mission risk, increases crew independence and improves the overall supportability of the program. The Component-Level Electronics Assembly Repair (CLEAR) task under the NASA Supportability program was established to demonstrate the practicality of repair by first investigating widely used soldering materials and processes (M&P) performed by modest manual means. The work will result in program guidelines for performing manual repairs along with design guidance for circuit reparability. The next phase of CLEAR recognizes that manual repair has its limitations and some highly integrated devices are extremely difficult to handle and demand semi-automated equipment. Further, electronics repairs require a broad range of diagnostic capability to isolate the faulty components. Finally repairs must pass functional tests to determine that the repairs are successful and the circuit can be returned to service. To prevent equipment demands from exceeding spacecraft volume

Component Repair Times Obtained from MSPI Data

International Nuclear Information System (INIS)

Eide, Steven A.; Cadwallader, Lee

2015-01-01

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

Auto Body Repair 103, 203, 303.

Science.gov (United States)

Manitoba Dept. of Education, Winnipeg.

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

Factors affecting healing after arthroscopic rotator cuff repair

Science.gov (United States)

Abtahi, Amir M; Granger, Erin K; Tashjian, Robert Z

2015-01-01

Rotator cuff repair has been shown to have good long-term results. Unfortunately, a significant proportion of repairs still fail to heal. Many factors, both patient and surgeon related, can influence healing after repair. Older age, larger tear size, worse muscle quality, greater muscle-tendon unit retraction, smoking, osteoporosis, diabetes and hypercholesterolemia have all shown to negatively influence tendon healing. Surgeon related factors that can influence healing include repair construct-single vs double row, rehabilitation, and biologics including platelet rich plasma and mesenchymal stem cells. Double-row repairs are biomechanically stronger and have better healing rates compared with single-row repairs although clinical outcomes are equivalent between both constructs. Slower, less aggressive rehabilitation programs have demonstrated improved healing with no negative effect on final range of motion and are therefore recommended after repair of most full thickness tears. Additionally no definitive evidence supports the use of platelet rich plasma or mesenchymal stem cells regarding improvement of healing rates and clinical outcomes. Further research is needed to identify effective biologically directed augmentations that will improve healing rates and clinical outcomes after rotator cuff repair. PMID:25793161

Workplace safety and health programs, practices, and conditions in auto collision repair businesses.

Science.gov (United States)

Brosseau, L M; Bejan, A; Parker, D L; Skan, M; Xi, M

2014-01-01

This article describes the results of a pre-intervention safety assessment conducted in 49 auto collision repair businesses and owners' commitments to specific improvements. A 92-item standardized audit tool employed interviews, record reviews, and observations to assess safety and health programs, training, and workplace conditions. Owners were asked to improve at least one-third of incorrect, deficient, or missing (not in compliance with regulations or not meeting best practice) items, of which a majority were critical or highly important for ensuring workplace safety. Two-thirds of all items were present, with the highest fraction related to electrical safety, machine safety, and lockout/tagout. One-half of shops did not have written safety programs and had not conducted recent training. Many had deficiencies in respiratory protection programs and practices. Thirteen businesses with a current or past relationship with a safety consultant had a significantly higher fraction of correct items, in particular related to safety programs, up-to-date training, paint booth and mixing room conditions, electrical safety, and respiratory protection. Owners selected an average of 58% of recommended improvements; they were most likely to select items related to employee Right-to-Know training, emergency exits, fire extinguishers, and respiratory protection. They were least likely to say they would improve written safety programs, stop routine spraying outside the booth, or provide adequate fire protection for spray areas outside the booth. These baseline results suggest that it may be possible to bring about workplace improvements using targeted assistance from occupational health and safety professionals.

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

Energy Technology Data Exchange (ETDEWEB)

Roach, Dennis Patrick; Rackow, Kirk A.

2007-07-01

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

DNA repair , cell repair and radiosensitivity

International Nuclear Information System (INIS)

Zhestyanikov, V.D.

1983-01-01

Data obtained in laboratory of radiation cytology and literature data testifying to a considerable role of DNA repair in cell sensitivity to radiation and chemical DNA-tropic agents have been considered. Data pointing to the probability of contribution of inducible repair of DNA into plant cells sensitivity to X-rays are obtained. Certain violations of DNA repair do not result in the increase of radiosensitivity. It is assumed that in the cases unknown mechanisms of DNA repair operate

Fission yeast mating-type switching: programmed damage and repair

DEFF Research Database (Denmark)

Egel, Richard

2005-01-01

Mating-type switching in fission yeast follows similar rules as in budding yeast, but the underlying mechanisms are entirely different. Whilst the initiating double-strand cut in Saccharomyces cerevisiae requires recombinational repair for survival, the initial damage in Schizosaccharomyces pombe...

Honolulu Community College Program Health Indicators: 2000-2001 Program Reviews.

Science.gov (United States)

Hawaii Univ., Honolulu. Honolulu Community Coll.

This report presents an overall health summation of 21 programs offered at Honolulu Community College (Hawaii) during 2000-2001. The programs profiled are: (1) Auto Body Repair and Painting; (2) Aeronautics Maintenance Technology; (3) Administration of Justice; (4) Automotive Mechanics Technology; (5) Boat Maintenance Repair; (6) Carpentry; (7)…

Role of DNA repair in repair of cytogenetic damages. Slowly repaired DNA injuries involved in cytogenetic damages repair

International Nuclear Information System (INIS)

Zaichkina, S.I.; Rozanova, O.M.; Aptikaev, G.F.; Ganassi, E.Eh.

1989-01-01

Caffeine was used to study the kinetics of cytogenetic damages repair in Chinese hamster fibroblasts. Its half-time (90 min) was shown to correlate with that of repair of slowly repaired DNA damages. The caffeine-induced increase in the number of irreparable DNA damages, attributed to inhibition of double-strand break repair, is in a quantitative correlation with the effect of the cytogenetic damage modification

DNA Repair and Genome Maintenance in Bacillus subtilis

Science.gov (United States)

Lenhart, Justin S.; Schroeder, Jeremy W.; Walsh, Brian W.

2012-01-01

Summary: From microbes to multicellular eukaryotic organisms, all cells contain pathways responsible for genome maintenance. DNA replication allows for the faithful duplication of the genome, whereas DNA repair pathways preserve DNA integrity in response to damage originating from endogenous and exogenous sources. The basic pathways important for DNA replication and repair are often conserved throughout biology. In bacteria, high-fidelity repair is balanced with low-fidelity repair and mutagenesis. Such a balance is important for maintaining viability while providing an opportunity for the advantageous selection of mutations when faced with a changing environment. Over the last decade, studies of DNA repair pathways in bacteria have demonstrated considerable differences between Gram-positive and Gram-negative organisms. Here we review and discuss the DNA repair, genome maintenance, and DNA damage checkpoint pathways of the Gram-positive bacterium Bacillus subtilis. We present their molecular mechanisms and compare the functions and regulation of several pathways with known information on other organisms. We also discuss DNA repair during different growth phases and the developmental program of sporulation. In summary, we present a review of the function, regulation, and molecular mechanisms of DNA repair and mutagenesis in Gram-positive bacteria, with a strong emphasis on B. subtilis. PMID:22933559

Role of DNA repair in repair of cytogenetic damages. Contribution of repair of single-strand DNA breaks to cytogenetic damages repair

International Nuclear Information System (INIS)

Rozanova, O.M.; Zaichkina, S.I.; Aptikaev, G.F.; Ganassi, E.Eh.

1989-01-01

The comparison was made between the results of the effect of poly(ADP-ribosylation) ingibitors (e.g. nicotinamide and 3-aminobenzamide) and a chromatin proteinase ingibitor, phenylmethylsulfonylfluoride, on the cytogenetic damages repair, by a micronuclear test, and DNA repair in Chinese hamster fibroblasts. The values of the repair half-periods (5-7 min for the cytogenetic damages and 5 min for the rapidly repaired DNA damages) and a similar modyfying effect with regard to radiation cytogenetic damages and kynetics of DNA damages repair were found to be close. This confirms the contribution of repair of DNA single-strand breaks in the initiation of structural damages to chromosomes

DNA repair

International Nuclear Information System (INIS)

Setlow, R.

1978-01-01

Some topics discussed are as follows: difficulty in extrapolating data from E. coli to mammalian systems; mutations caused by UV-induced changes in DNA; mutants deficient in excision repair; other postreplication mechanisms; kinds of excision repair systems; detection of repair by biochemical or biophysical means; human mutants deficient in repair; mutagenic effects of UV on XP cells; and detection of UV-repair defects among XP individuals

Wellbore Seal Repair Using Nanocomposite Materials

Energy Technology Data Exchange (ETDEWEB)

Stormont, John [Univ. of New Mexico, Albuquerque, NM (United States)

2016-08-31

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

CrowdAidRepair: A Crowd-Aided Interactive Data Repairing Method

KAUST Repository

Zhou, Jian

2016-03-25

Data repairing aims at discovering and correcting erroneous data in databases. Traditional methods relying on predefined quality rules to detect the conflict between data may fail to choose the right way to fix the detected conflict. Recent efforts turn to use the power of crowd in data repairing, but the crowd power has its own drawbacks such as high human intervention cost and inevitable low efficiency. In this paper, we propose a crowd-aided interactive data repairing method which takes the advantages of both rule-based method and crowd-based method. Particularly, we investigate the interaction between crowd-based repairing and rule-based repairing, and show that by doing crowd-based repairing to a small portion of values, we can greatly improve the repairing quality of the rule-based repairing method. Although we prove that the optimal interaction scheme using the least number of values for crowd-based repairing to maximize the imputation recall is not feasible to be achieved, still, our proposed solution identifies an efficient scheme through investigating the inconsistencies and the dependencies between values in the repairing process. Our empirical study on three data collections demonstrates the high repairing quality of CrowdAidRepair, as well as the efficiency of the generated interaction scheme over baselines.

Value maximizing maintenance policies under general repair

International Nuclear Information System (INIS)

Marais, Karen B.

2013-01-01

One class of maintenance optimization problems considers the notion of general repair maintenance policies where systems are repaired or replaced on failure. In each case the optimality is based on minimizing the total maintenance cost of the system. These cost-centric optimizations ignore the value dimension of maintenance and can lead to maintenance strategies that do not maximize system value. This paper applies these ideas to the general repair optimization problem using a semi-Markov decision process, discounted cash flow techniques, and dynamic programming to identify the value-optimal actions for any given time and system condition. The impact of several parameters on maintenance strategy, such as operating cost and revenue, system failure characteristics, repair and replacement costs, and the planning time horizon, is explored. This approach provides a quantitative basis on which to base maintenance strategy decisions that contribute to system value. These decisions are different from those suggested by traditional cost-based approaches. The results show (1) how the optimal action for a given time and condition changes as replacement and repair costs change, and identifies the point at which these costs become too high for profitable system operation; (2) that for shorter planning horizons it is better to repair, since there is no time to reap the benefits of increased operating profit and reliability; (3) how the value-optimal maintenance policy is affected by the system's failure characteristics, and hence whether it is worthwhile to invest in higher reliability; and (4) the impact of the repair level on the optimal maintenance policy. -- Highlights: •Provides a quantitative basis for maintenance strategy decisions that contribute to system value. •Shows how the optimal action for a given condition changes as replacement and repair costs change. •Shows how the optimal policy is affected by the system's failure characteristics. •Shows when it is

A Review of the Labor Market, Manpower Characteristics and Training of Motor Vehicle Repair Personnel. Final Report.

Science.gov (United States)

McCutcheon, R. W.; And Others

To determine whether current automotive mechanic training programs provide adequate exposure to the knowledge and skills needed to properly service and repair motor vehicles, data were gathered on the tasks, service and repair establishments, job market, labor force, and training programs. Primary sources of data are reports prepared by various…

Cell Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath

Science.gov (United States)

2017-07-01

to subsequently guide tissue regeneration , for example, by seeded tissue progenitor cells . To achieve this objective, the first step is to develop...AWARD NUMBER: W81XWH-15-1-0104 TITLE: Cell -Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath PRINCIPAL INVESTIGATOR...SUBTITLE 5a. CONTRACT NUMBER Cell -Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath 5b. GRANT NUMBER W81XWH-15-1-0104 5c. PROGRAM

Telemetry Group Inter-Range Instrumentation Group Range Commanders Council

Science.gov (United States)

1975-11-01

PMR-AFWR-NWC- AFETR -•AMTEC-ADTC-AFFTC-AFSCF REPLY TO STEWS-SA-R ATTN OF, SuWu, IRIG Standard 106-73 (Revised November 1975) TO% Holders of IRIG...ETV-TM-67-16, "Multiple-Link Reception Through Wideband Nonlinear Components," 31 March 1967. 1. Purpose - To provide guidelines for the most effective ...telemetering must be restricted to .the 1435-1535 MHz and 2200-2300 MHz bands, effective 1 January 1970, in ord’er to permit unrestricted use of the 225-400

AVACOM-ETAP, Availability and Element Transient and Asymptotic Repair Process

International Nuclear Information System (INIS)

Reina, G.

1987-01-01

1 - Description of program or function: In reliability theory, the term 'availability' generally indicates the probability of the proper functioning of a system or of a component at a general time t when various possible replacement or repair policies are considered. AVACOM-ETARP calculates the transient and asymptotic availability of a component subject to a repair process with generic failure and repair laws. Five of the most commonly used distributions have been included as options: exponential, normal; lognormal; gamma; Weibull. 2 - Method of solution: The used mathematical model considers the failure-restoration process as a 2-state non-homogeneous Markov process containing the homogeneous Markov one as a particular case

Efficacy of Low Level Laser Therapy After Hand Flexor Tendon Repair

Science.gov (United States)

Ayad, K. E.; El Gohary, H. M.; Abd Elrahman, M.; Abd El Mejeed, S. F.; Bekheet, A. B.

2009-09-01

Flexor tendon injury is a common problem requiring suturing repair followed by early postoperative mobilization. Muscle atrophy, joint stiffness, osteoarthritis, infection, skin necrosis, ulceration of joint cartilage and tendocutaneous adhesion are familiar complications produced by prolonged immobilization of surgically repaired tendon ruptures. The purpose of this study was to clarify the importance of low level laser therapy after hand flexor tendon repair in zone II. Thirty patients aging between 20 and 40 years were divided into two groups. Patients in group A (n = 15) received a conventional therapeutic exercise program while patients in group B (n = 15) received low level laser therapy combined with the same therapeutic exercise program. The results showed a statistically significant increase in total active motion of the proximal and distal interphalangeal joints as well as maximum hand grip strength at three weeks and three months postoperative, but improvement was more significant in group B. It was concluded that the combination of low level laser therapy and early therapeutic exercises was more effective than therapeutic exercises alone in improving total active motion of proximal and distal interphalangeal joints and hand grip strength after hand flexor tendon repair.

Repairable-conditionally repairable damage model based on dual Poisson processes.

Science.gov (United States)

Lind, B K; Persson, L M; Edgren, M R; Hedlöf, I; Brahme, A

2003-09-01

The advent of intensity-modulated radiation therapy makes it increasingly important to model the response accurately when large volumes of normal tissues are irradiated by controlled graded dose distributions aimed at maximizing tumor cure and minimizing normal tissue toxicity. The cell survival model proposed here is very useful and flexible for accurate description of the response of healthy tissues as well as tumors in classical and truly radiobiologically optimized radiation therapy. The repairable-conditionally repairable (RCR) model distinguishes between two different types of damage, namely the potentially repairable, which may also be lethal, i.e. if unrepaired or misrepaired, and the conditionally repairable, which may be repaired or may lead to apoptosis if it has not been repaired correctly. When potentially repairable damage is being repaired, for example by nonhomologous end joining, conditionally repairable damage may require in addition a high-fidelity correction by homologous repair. The induction of both types of damage is assumed to be described by Poisson statistics. The resultant cell survival expression has the unique ability to fit most experimental data well at low doses (the initial hypersensitive range), intermediate doses (on the shoulder of the survival curve), and high doses (on the quasi-exponential region of the survival curve). The complete Poisson expression can be approximated well by a simple bi-exponential cell survival expression, S(D) = e(-aD) + bDe(-cD), where the first term describes the survival of undamaged cells and the last term represents survival after complete repair of sublethal damage. The bi-exponential expression makes it easy to derive D(0), D(q), n and alpha, beta values to facilitate comparison with classical cell survival models.

Tissue repair capacity and repair kinetics deduced from multifractionated or continuous irradiation regimens with incomplete repair

International Nuclear Information System (INIS)

Thames, H.D. Jr.; Peters, L.J.

1984-01-01

A model is proposed for cell survival after multiple doses, when the interfraction interval is insufficient for complete Elkind repair. In the limit of ever-increasing number of ever-smaller fractional doses, the model transforms into the accumulation model of survival after continuous irradiation. When adapted to describe tissue responses to isoeffective multifractionated regimens, wherein repair is incomplete, a generalization of the usually linear plot of reciprocal total dose versus dose per fraction is obtained, in which downward curvature is evident. There is an advantage in studying tissue responses to multifractionated regimens with incomplete repair in the interfraction intervals, or continuous exposures at various dose rates since, in addition to determination of repair capacity, there is an estimate of repair kinetics. Results of analyses of previously published data are presented as illustration. Estimated from the response of three acutely responding normal tissues in the mouse (jejunum, colon and bone marrow), repair halftimes ranged from 0.3-0.9 h and values of β/delta were approximately 0.1 Gy -1 . From the response of mouse lung (LD50 for pneumonitis) to multifractionated regimens with incomplete repair, the repair halftime was estimated at 1.5 h and β/delta was 0.27 Gy -1 . In the rat spinal cord β/delta was 0.7 Gy -1 and Tsub(1/2) was 1.5 h. (U.K.)

Comparing Biomechanical Properties, Repair Times, and Value of Common Core Flexor Tendon Repairs.

Science.gov (United States)

Chauhan, Aakash; Schimoler, Patrick; Miller, Mark C; Kharlamov, Alexander; Merrell, Gregory A; Palmer, Bradley A

2018-05-01

The aim of the study was to compare biomechanical strength, repair times, and repair values for zone II core flexor tendon repairs. A total of 75 fresh-frozen human cadaveric flexor tendons were harvested from the index through small finger and randomized into one of 5 repair groups: 4-stranded cross-stitch cruciate (4-0 polyester and 4-0 braided suture), 4-stranded double Pennington (2-0 knotless barbed suture), 4-stranded Pennington (4-0 double-stranded braided suture), and 6-stranded modified Lim-Tsai (4-0 looped braided suture). Repairs were measured in situ and their repair times were measured. Tendons were linearly loaded to failure and multiple biomechanical values were measured. The repair value was calculated based on operating room costs, repair times, and suture costs. Analysis of variance (ANOVA) and Tukey post hoc statistical analysis were used to compare repair data. The braided cruciate was the strongest repair ( P > .05) but the slowest ( P > .05), and the 4-stranded Pennington using double-stranded suture was the fastest ( P > .05) to perform. The total repair value was the highest for braided cruciate ( P > .05) compared with all other repairs. Barbed suture did not outperform any repairs in any categories. The braided cruciate was the strongest of the tested flexor tendon repairs. The 2-mm gapping and maximum load to failure for this repair approached similar historical strength of other 6- and 8-stranded repairs. In this study, suture cost was negligible in the overall repair cost and should be not a determining factor in choosing a repair.

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

International Nuclear Information System (INIS)

NONE

1999-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-02-12

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

Component-Level Electronic-Assembly Repair (CLEAR) Operational Concept

Science.gov (United States)

Oeftering, Richard C.; Bradish, Martin A.; Juergens, Jeffrey R.; Lewis, Michael J.; Vrnak, Daniel R.

2011-01-01

This Component-Level Electronic-Assembly Repair (CLEAR) Operational Concept document was developed as a first step in developing the Component-Level Electronic-Assembly Repair (CLEAR) System Architecture (NASA/TM-2011-216956). The CLEAR operational concept defines how the system will be used by the Constellation Program and what needs it meets. The document creates scenarios for major elements of the CLEAR architecture. These scenarios are generic enough to apply to near-Earth, Moon, and Mars missions. The CLEAR operational concept involves basic assumptions about the overall program architecture and interactions with the CLEAR system architecture. The assumptions include spacecraft and operational constraints for near-Earth orbit, Moon, and Mars missions. This document addresses an incremental development strategy where capabilities evolve over time, but it is structured to prevent obsolescence. The approach minimizes flight hardware by exploiting Internet-like telecommunications that enables CLEAR capabilities to remain on Earth and to be uplinked as needed. To minimize crew time and operational cost, CLEAR exploits offline development and validation to support online teleoperations. Operational concept scenarios are developed for diagnostics, repair, and functional test operations. Many of the supporting functions defined in these operational scenarios are further defined as technologies in NASA/TM-2011-216956.

Developing a Model for Optimizing Inventory of Repairable Items at Single Operating Base

OpenAIRE

Le, Tin

2016-01-01

The use of EOQ model in inventory management is popular. However, EOQ models has many disadvantages, especially, when the model is applied to manage repairable items. In order to deal with high-cost and repairable items, Craig C. Sherbrooke introduced a model in his book “Optimal Inventory Modeling of Systems: Multi-Echelon Techniques”. The research focus is to implement and develop a program to execute the single-site in-ventory model for repairable items. The model helps to significantl...

Brain aneurysm repair

Science.gov (United States)

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

Rapid road repair vehicle

Science.gov (United States)

Mara, Leo M.

1998-01-01

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

Optimizing pressurized contact area in rotator cuff repair: the diamondback repair.

Science.gov (United States)

Burkhart, Stephen S; Denard, Patrick J; Obopilwe, Elifho; Mazzocca, Augustus D

2012-02-01

The purpose of this study was to compare tendon-bone footprint contact area over time under physiologic loads for 4 different rotator cuff repair techniques: single row (SR), triangle double row (DR), chain-link double row (CL), and diamondback double row (DBK). A supraspinatus tear was created in 28 human cadavers. Tears were fixed with 1 of 4 constructs: SR, DR, CL, or DBK. Immediate post-repair measurements of pressurized contact area were taken in neutral rotation and 0° of abduction. After a static tensile load, pressurized contact area was observed over a 160-minute period after repair. Cyclic loading was then performed. The DBK repair had the highest pressurized contact area initially, as well as the highest pressurized contact area and lowest percentage decrease in pressurized contact area after 160 minutes of testing. The DBK repair had significantly larger initial pressurized contact than CL (P = .003) and SR (P = .004) but not DR (P = .06). The DBK technique was the only technique that produced a pressurized contact area that exceeded the native footprint both at initial repair (P = .01) and after 160 minutes of testing (P = .01). DBK had a significantly larger mean pressurized contact area than all the repairs after 160 minutes of testing (P = .01). DBK had a significantly larger post-cyclic loading pressurized contact area than CL (P = .01) and SR (P = .004) but not DR (P = .07). This study showed that a diamondback repair (a modification of the transosseous repair) can significantly increase the rotator cuff pressurized contact area in comparison with other standard rotator cuff repair constructs when there is sufficient tendon mobility to perform a double-row repair without excessive tension on the repair site. The persistent pressurized contact area of a DBK repair may be desirable to enhance healing potential when there is sufficient tendon mobility to perform a double-row repair, particularly for large or massive rotator cuff tears where it is

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

Energy Technology Data Exchange (ETDEWEB)

Roach, David W.; Rackow, Kirk A.

2005-06-01

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

The Design of Intelligent Repair Welding Mechanism and Relative Control System of Big Gear

Directory of Open Access Journals (Sweden)

Hong-Yu LIU

2014-10-01

Full Text Available Effective repair of worn big gear has large influence on ensuring safety production and enhancing economic benefits. A kind of intelligent repair welding method was put forward mainly aimed at the big gear restriction conditions of high production cost, long production cycle and high- intensity artificial repair welding work. Big gear repair welding mechanism was designed in this paper. The work principle and part selection of big gear repair welding mechanism was introduced. The three dimensional mode of big gear repair welding mechanism was constructed by Pro/E three dimensional design software. Three dimensional motions can be realized by motor controlling ball screw. According to involute gear feature, the complicated curve motion on curved gear surface can be transformed to linear motion by orientation. By this way, the repair welding on worn gear area can be realized. In the design of big gear repair welding mechanism control system, Siemens S7-200 series hardware was chosen. Siemens STEP7 programming software was chosen as system design tool. The entire repair welding process was simulated by experiment simulation. It provides a kind of practical and feasible method for the intelligent repair welding of big worn gear.

A spacecraft computer repairable via command.

Science.gov (United States)

Fimmel, R. O.; Baker, T. E.

1971-01-01

The MULTIPAC is a central data system developed for deep-space probes with the distinctive feature that it may be repaired during flight via command and telemetry links by reprogramming around the failed unit. The computer organization uses pools of identical modules which the program organizes into one or more computers called processors. The interaction of these modules is dynamically controlled by the program rather than hardware. In the event of a failure, new programs are entered which reorganize the central data system with a somewhat reduced total processing capability aboard the spacecraft. Emphasis is placed on the evolution of the system architecture and the final overall system design rather than the specific logic design.

Remote tooling for inspection and repair in Pickering NGS-A calandria vault

International Nuclear Information System (INIS)

Hadji-Mirzai, M.; Tokarz, A.; Vandenberg, J.P.

1993-01-01

In recent years it has been necessary to develop capabilities for the inspection and repair of carbon steel components located within calandria vaults at Ontario Hydro's Pickering Nuclear Generating Station 'A'. Concerns about corrosion of piping and some of the structural components have made necessary the development of remote manipulators to inspect and repair carbon steel components within the vaults to ensure continued reliable operation of the units. Remote manipulators for this program have been designed to perform a number of inspection and repair tasks, and several versions have been developed to specialise in detailed inspection techniques and precision tooling module manipulation. (author)

The timing of spontaneous detection and repair of naming errors in aphasia.

Science.gov (United States)

Schuchard, Julia; Middleton, Erica L; Schwartz, Myrna F

2017-08-01

This study examined the timing of spontaneous self-monitoring in the naming responses of people with aphasia. Twelve people with aphasia completed a 615-item naming test twice, in separate sessions. Naming attempts were scored for accuracy and error type, and verbalizations indicating detection were coded as negation (e.g., "no, not that") or repair attempts (i.e., a changed naming attempt). Focusing on phonological and semantic errors, we measured the timing of the errors and of the utterances that provided evidence of detection. The effects of error type and detection response type on error-to-detection latencies were analyzed using mixed-effects regression modeling. We first asked whether phonological errors and semantic errors differed in the timing of the detection process or repair planning. Results suggested that the two error types primarily differed with respect to repair planning. Specifically, repair attempts for phonological errors were initiated more quickly than repair attempts for semantic errors. We next asked whether this difference between the error types could be attributed to the tendency for phonological errors to have a high degree of phonological similarity with the subsequent repair attempts, thereby speeding the programming of the repairs. Results showed that greater phonological similarity between the error and the repair was associated with faster repair times for both error types, providing evidence of error-to-repair priming in spontaneous self-monitoring. When controlling for phonological overlap, significant effects of error type and repair accuracy on repair times were also found. These effects indicated that correct repairs of phonological errors were initiated particularly quickly, whereas repairs of semantic errors were initiated relatively slowly, regardless of their accuracy. We discuss the implications of these findings for theoretical accounts of self-monitoring and the role of speech error repair in learning. Copyright �

Criteria for maintenance and repair - LMFBR steam generators

International Nuclear Information System (INIS)

Essebaggers, J.

1975-01-01

The maintenance and repair criteria will be reviewed with respect to the designs presently under construction for the SNR-300 plant. This criteria shall be based upon the philosophy that safety and reliability are of the highest importance at all operating modes, while availability shall be maximized. To maximize the safety of the steam generator, measures have been taken to reduce the possibilities of failure by simplicity in design, choice of material, methods of fabrication and high quality assurance of critical parts of the pressure boundaries. The maintenance and repair program shall meet the same criteria or the intent of these criteria as applied for the original product. (author)

DNA repair

International Nuclear Information System (INIS)

Van Zeeland, A.A.

1984-01-01

In this chapter a series of DNA repair pathways are discussed which are available to the cell to cope with the problem of DNA damaged by chemical or physical agents. In the case of microorganisms our knowledge about the precise mechanism of each DNA repair pathway and the regulation of it has been improved considerably when mutants deficient in these repair mechanisms became available. In the case of mammalian cells in culture, until recently there were very little repair deficient mutants available, because in almost all mammalian cells in culture at least the diploid number of chromosomes is present. Therefore the frequency of repair deficient mutants in such populations is very low. Nevertheless because replica plating techniques are improving some mutants from Chinese hamsters ovary cells and L5178Y mouse lymphoma cells are now available. In the case of human cells, cultures obtained from patients with certain genetic diseases are available. A number of cells appear to be sensitive to some chemical or physical mutagens. These include cells from patients suffering from xeroderma pigmentosum, Ataxia telangiectasia, Fanconi's anemia, Cockayne's syndrome. However, only in the case of xeroderma pigmentosum cells, has the sensitivity to ultraviolet light been clearly correlated with a deficiency in excision repair of pyrimidine dimers. Furthermore the work with strains obtained from biopsies from man is difficult because these cells generally have low cloning efficiencies and also have a limited lifespan in vitro. It is therefore very important that more repair deficient mutants will become available from established cell lines from human or animal origin

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

Energy Technology Data Exchange (ETDEWEB)

Oland, C.B.; Naus, D.J. [Oak Ridge National Lab., TN (United States)

1998-05-01

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

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

International Nuclear Information System (INIS)

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

1998-05-01

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

Residual strength of repaired graphite/epoxy laminates after 5 years of outdoor exposure

Science.gov (United States)

Deaton, Jerry W.

1990-01-01

The NASA Langley Research Center has sponsored research to develop generic repair techniques and processes for advanced graphite/epoxy (Gr/Ep) composites applicable to secondary structures for commercial transport aircraft. The long-term durability of such repairs is being addressed in a 10-year outdoor exposure program at the Langley Research Center. Details of the program and results of residual strength tests after 5 years of outdoor exposure are presented. Four repair methods are being evaluated. These include: (1) externally bolted aluminum-plus adhesive; (2) precured, bonded external Gr/Ep; (3) cure-in-place external Gr/Ep; and (4) cure-in-place flush Gr/Ep. Repaired specimens as well as undamaged and damaged unrepaired controls are being exposed outdoors for 1, 3, 5, 7, and 10 years. The residual tensile strength of stressed, unstressed, and fatigue specimens from each group is reported and compared with the tensile strength of baseline specimens which received no outdoor exposure. Identification of the commercial products and companies is used to describe adequately the test materials. The identification of these commercial products does not constitute endorsement, expressed or implied, of such products by the National Aeronautics and Space Administration.

Repairing liner of the reactor

International Nuclear Information System (INIS)

Aguilar H, F.

2001-07-01

Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

Repair kinetics in tissues

International Nuclear Information System (INIS)

Thames, H.D.

1989-01-01

Monoexponential repair kinetics is based on the assumption of a single, dose-independent rate of repair of sublethal injury in the target cells for tissue injury after exposure to ionizing radiation. Descriptions of the available data based on this assumption have proved fairly successful for both acutely responding (skin, lip mucosa, gut) and late-responding (lung, spinal cord) normal tissues. There are indications of biphasic exponential repair in both categories, however. Unfortunately, the data usually lack sufficient resolution to permit unambiguous determination of the repair rates. There are also indications that repair kinetics may depend on the size of the dose. The data are conflicting on this account, however, with suggestions of both faster and slower repair after larger doses. Indeed, experiments that have been explicitly designed to test this hypothesis show either no effect (gut, spinal cord), faster repair after higher doses (lung, kidney), or slower repair after higher doses (skin). Monoexponential repair appears to be a fairly accurate description that provides an approximation to a more complicated picture, the elucidation of whose details will, however, require very careful and extensive experimental study. (author). 30 refs.; 1 fig

DNA Double Strand Break Response and Limited Repair Capacity in Mouse Elongated Spermatids

Directory of Open Access Journals (Sweden)

Emad A. Ahmed

2015-12-01

Full Text Available Spermatids are extremely sensitive to genotoxic exposures since during spermiogenesis only error-prone non homologous end joining (NHEJ repair pathways are available. Hence, genomic damage may accumulate in sperm and be transmitted to the zygote. Indirect, delayed DNA fragmentation and lesions associated with apoptotic-like processes have been observed during spermatid elongation, 27 days after irradiation. The proliferating spermatogonia and early meiotic prophase cells have been suggested to retain a memory of a radiation insult leading later to this delayed fragmentation. Here, we used meiotic spread preparations to localize phosphorylate histone H2 variant (γ-H2AX foci marking DNA double strand breaks (DSBs in elongated spermatids. This technique enabled us to determine the background level of DSB foci in elongated spermatids of RAD54/RAD54B double knockout (dko mice, severe combined immunodeficiency SCID mice, and poly adenosine diphosphate (ADP-ribose polymerase 1 (PARP1 inhibitor (DPQ-treated mice to compare them with the appropriate wild type controls. The repair kinetics data and the protein expression patterns observed indicate that the conventional NHEJ repair pathway is not available for elongated spermatids to repair the programmed and the IR-induced DSBs, reflecting the limited repair capacity of these cells. However, although elongated spermatids express the proteins of the alternative NHEJ, PARP1-inhibition had no effect on the repair kinetics after IR, suggesting that DNA damage may be passed onto sperm. Finally, our genetic mutant analysis suggests that an incomplete or defective meiotic recombinational repair of Spo11-induced DSBs may lead to a carry-over of the DSB damage or induce a delayed nuclear fragmentation during the sensitive programmed chromatin remodeling occurring in elongated spermatids.

A geometric process repair model for a repairable cold standby system with priority in use and repair

International Nuclear Information System (INIS)

Zhang Yuanlin; Wang Guanjun

2009-01-01

In this paper, a deteriorating cold standby repairable system consisting of two dissimilar components and one repairman is studied. For each component, assume that the successive working times form a decreasing geometric process while the consecutive repair times constitute an increasing geometric process, and component 1 has priority in use and repair. Under these assumptions, we consider a replacement policy N based on the number of repairs of component 1 under which the system is replaced when the number of repairs of component 1 reaches N. Our problem is to determine an optimal policy N* such that the average cost rate (i.e. the long-run average cost per unit time) of the system is minimized. The explicit equation of the average cost rate of the system is derived and the corresponding optimal replacement policy N* can be determined analytically or numerically. Finally, a numerical example with Weibull distribution is given to illustrate some theoretical results in this paper.

Phenomenology of an inducible mutagenic DNA repair pathway in Escherichia coli: SOS repair hypothesis

International Nuclear Information System (INIS)

Radman, M.

1974-01-01

A hypothesis is proposed according to which E. coli possesses an inducible DNA repair system. This hypothetical repair, which we call SOS repair, is manifested only following damage to DNA, and requires de novo protein synthesis. SOS repair in E. coli requires some known genetic elements: recA + , lex + and probably zab + . Mutagenesis by ultraviolet light is observed only under conditions of functional SOS repair: we therefore suspect that this is a mutation-prone repair. A number of phenomena and experiments is reviewed which at this point can best be interpreted in terms of an inducible mutagenic DNA repair system. Two recently discovered phenomena support the proposed hypothesis: existence of a mutant (tif) which, after a shift to elevated temperature, mimicks the effect of uv irradiation in regard to repair of phage lambda and uv mutagenesis, apparent activation of SOS repair by introduction into the recipient cell of damaged plasmid or Hfr DNA. Several specific predictions based on SOS repair hypothesis are presented in order to stimulate further experimental tests. (U.S.)

X-ray repair cross complementing protein 1 in base excision repair

DEFF Research Database (Denmark)

Hanssen-Bauer, Audun; Solvang-Garten, Karin; Akbari, Mansour

2012-01-01

X-ray Repair Cross Complementing protein 1 (XRCC1) acts as a scaffolding protein in the converging base excision repair (BER) and single strand break repair (SSBR) pathways. XRCC1 also interacts with itself and rapidly accumulates at sites of DNA damage. XRCC1 can thus mediate the assembly of large...

Analysis for a two-dissimilar-component cold standby repairable system with repair priority

International Nuclear Information System (INIS)

Leung, Kit Nam Francis; Zhang Yuanlin; Lai, Kin Keung

2011-01-01

In this paper, a cold standby repairable system consisting of two dissimilar components and one repairman is studied. Assume that working time distributions and repair time distributions of the two components are both exponential, and Component 1 has repair priority when both components are broken down. After repair, Component 1 follows a geometric process repair while Component 2 obeys a perfect repair. Under these assumptions, using the perfect repair model, the geometric process repair model and the supplementary variable technique, we not only study some important reliability indices, but also consider a replacement policy T, under which the system is replaced when the working age of Component 1 reaches T. Our problem is to determine an optimal policy T* such that the long-run average loss per unit time (i.e. average loss rate) of the system is minimized. The explicit expression for the average loss rate of the system is derived, and the corresponding optimal replacement policy T* can be found numerically. Finally, a numerical example for replacement policy T is given to illustrate some theoretical results and the model's applicability. - Highlights: → A two-dissimilar-component cold standby system with repair priority is formulated. → The successive up/repair times of Component 1 form a decreasing/increasing geometric process. → Not only some reliability indices but also a replacement policy are studied.

Risk factors for morbidity in infants undergoing tetralogy of fallot repair

Directory of Open Access Journals (Sweden)

Alexander C Egbe

2014-01-01

Full Text Available Background: Primary repair of tetralogy of Fallot (TOF has low surgical mortality, but some patients still experience significant postoperative morbidity. Aim: To review our institutional experience with primary TOF repair, and identify predictors of intensive care unit (ICU morbidity. Settings and Design: Medium-sized pediatric cardiology program. Retrospective study. Subjects and Methods: We retrospectively reviewed all the patients with TOF and pulmonic stenosis who underwent primary repair in infancy at our institution from January 2001 to December 2012. Preoperative, operative, and postoperative demographic and morphologic data were analyzed. ICU morbidity was defined as prolonged ICU stay (≥7 days, and/or prolonged duration of mechanical ventilation (≥48 h. Statistical Analysis Used: Multiple logistic regression analysis. Results: Ninety-seven patients underwent primary surgical repair during the study period. The median age was 4.9 months (1-9 months and the median weight was 5.3 kg (3.1-9.8 kg. There was no early surgical mortality. Incidence of junctional ectopic tachycardia (JET and persistent complete heart block was 2 and 1%, respectively. The median length of ICU stay was 6 days (2-21 days and median duration of mechanical ventilation was 19 h (0-136 h. By multiple regression analysis, age and weight were independent predictors of length of ICU stay, while surgical era was an independent predictor of duration of mechanical ventilation. Conclusion: Primary TOF repair is a safe procedure with low mortality and morbidity in a medium-sized program with outcomes comparable to national standards. Age and weight at the time of surgery remain significant predictors of morbidity.

RCC Plug Repair Thermal Tools for Shuttle Mission Support

Science.gov (United States)

Rodriguez, Alvaro C.; Anderson, Brian P.

2010-01-01

A thermal math model for the Space Shuttle Reinforced Carbon-Carbon (RCC) Plug Repair was developed to increase the confidence in the repair entry performance and provide a real-time mission support tool. The thermal response of the plug cover plate, local RCC, and metallic attach hardware can be assessed with this model for any location on the wing leading edge. The geometry and spatial location of the thermal mesh also matches the structural mesh which allows for the direct mapping of temperature loads and computation of the thermoelastic stresses. The thermal model was correlated to a full scale plug repair radiant test. To utilize the thermal model for flight analyses, accurate predictions of protuberance heating were required. Wind tunnel testing was performed at CUBRC to characterize the heat flux in both the radial and angular directions. Due to the complexity of the implementation of the protuberance heating, an intermediate program was developed to output the heating per nodal location for all OML surfaces in SINDA format. Three Design Reference Cases (DRC) were evaluated with the correlated plug thermal math model to bound the environments which the plug repair would potentially be used.

CARDIAC TRANSPLANT REJECTION AND NON-INVASIVE COMON CAROTID ARTERY WALL FUNCTIONAL INDICES

Directory of Open Access Journals (Sweden)

A. O. Shevchenko

2015-01-01

Full Text Available Allograft rejection would entail an increase in certain blood biomarkers and active substances derived from activated inflammatory cells which could influence entire vascular endothelial function and deteriorate arterial wall stiffness. We propose that carotid wall functional indices measured with non-invasive ultrasound could we valuable markers of the subclinical cardiac allograft rejection. Aim. Our goal was to analyze the clinical utility of functional common carotid wall (CCW variables measured with high-resolution Doppler ultrasound as a non-invasive screening tool for allograft rejection in cardiac transplant patients (pts. Methods. One hundred and seventy one pts included 93 cardiac recipients, 30 dilated cardiomyopathy waiting list pts, and 48 stable coronary artery disease (SCAD pts without decompensated heart failure were included. Along with resistive index (Ri, pulsative index (Pi, and CCW intima-media thickness (IMT, CCW rigidity index (iRIG was estimated using empirical equation. Non-invasive evaluation was performed in cardiac transplant recipients prior the endomyo- cardial biopsy. Results. Neither of Ri, Pi, or CCW IMT were different in studied subgroups. iRIG was signifi- cantly lower in SCAD pts when compared to the dilated cardiomyopathy subgroup. The later had similar values with cardiac transplant recipients without rejection. Antibody-mediated and cellular rejection were found in 22 (23.7% and 17 (18.3% cardiac recipients, respectively. Mean iRIG in pts without rejection was significantly lower in comparison to antibody-mediated rejection and cell-mediated (5514.7 ± 2404.0 vs 11856.1 ± 6643.5 and 16071.9 ± 10029.1 cm/sec2, respectively, p = 0.001. Area under ROC for iRIG was 0.90 ± 0.03 units2. Analysis showed that iRIG values above estimated treshold 7172 cm/sec2 suggested relative risk of any type of rejection 17.7 (95%CI = 6.3–49.9 sensitivity 80.5%, specificity – 81.1%, negative predictive value – 84

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

Science.gov (United States)

2010-07-01

... repair proficient and repair deficient bacteria: âBacterial DNA damage or repair tests.â 798.5500 Section... inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA damage or repair tests.” (a... killing or growth inhibition of repair deficient bacteria in a set of repair proficient and deficient...

DNA repair protocols

DEFF Research Database (Denmark)

Bjergbæk, Lotte

In its 3rd edition, this Methods in Molecular Biology(TM) book covers the eukaryotic response to genomic insult including advanced protocols and standard techniques in the field of DNA repair. Offers expert guidance for DNA repair, recombination, and replication. Current knowledge of the mechanisms...... that regulate DNA repair has grown significantly over the past years with technology advances such as RNA interference, advanced proteomics and microscopy as well as high throughput screens. The third edition of DNA Repair Protocols covers various aspects of the eukaryotic response to genomic insult including...... recent advanced protocols as well as standard techniques used in the field of DNA repair. Both mammalian and non-mammalian model organisms are covered in the book, and many of the techniques can be applied with only minor modifications to other systems than the one described. Written in the highly...

DNA repair in human cells

International Nuclear Information System (INIS)

Regan, J.D.; Carrier, W.L.; Kusano, I.; Furuno-Fukushi, I.; Dunn, W.C. Jr.; Francis, A.A.; Lee, W.H.

1982-01-01

Our primary objective is to elucidate the molecular events in human cells when cellular macromolecules such as DNA are damaged by radiation or chemical agents. We study and characterize (i) the sequence of DNA repair events, (ii) the various modalities of repair, (iii) the genetic inhibition of repair due to mutation, (iv) the physiological inhibition of repair due to mutation, (v) the physiological inhibition of repair due to biochemical inhibitors, and (vi) the genetic basis of repair. Our ultimate goals are to (i) isolate and analyze the repair component of the mutagenic and/or carcinogenic event in human cells, and (ii) elucidate the magnitude and significance of this repair component as it impinges on the practical problems of human irradiation or exposure to actual or potential chemical mutagens and carcinogens. The significance of these studies lies in (i) the ubiquitousness of repair (most organisms, including man, have several complex repair systems), (ii) the belief that mutagenic and carcinogenic events may arise only from residual (nonrepaired) lesions or that error-prone repair systems may be the major induction mechanisms of the mutagenic or carcinogenic event, and (iii) the clear association of repair defects and highly carcinogenic disease states in man [xeroderma pigmentosum (XP)

Flexor tendon repair: a comparative study between a knotless barbed suture repair and a traditional four-strand monofilament suture repair.

LENUS (Irish Health Repository)

Joyce, C W

2014-01-01

We compared the tensile strength of a novel knotless barbed suture method with a traditional four-strand Adelaide technique for flexor tendon repairs. Forty fresh porcine flexor tendons were transected and randomly assigned to one of the repair groups before repair. Biomechanical testing demonstrated that the tensile strengths between both tendon groups were very similar. However, less force was required to create a 2 mm gap in the four-strand repair method compared with the knotless barbed technique. There was a significant reduction in the cross-sectional area in the barbed suture group after repair compared with the Adelaide group. This would create better gliding within the pulley system in vivo and could decrease gapping and tendon rupture.

Employing Organizational Modeling and Simulation to Deconstruct the KC-135 Aircraft's Programmed Depot Maintenance Flight Controls Repair Cell

National Research Council Canada - National Science Library

Paskin, Matthew A; Trevino, Alice W

2007-01-01

...), Tinker Air Force Base, Oklahoma. The researchers focused on the repair cell's internal formal and informal communication flows and information processing to evaluate the impact on flight controls repair throughput time...

Basalt FRP Spike Repairing of Wood Beams

Directory of Open Access Journals (Sweden)

Luca Righetti

2015-08-01

Full Text Available This article describes aspects within an experimental program aimed at improving the structural performance of cracked solid fir-wood beams repaired with Basalt Fiber Reinforced Polymer (BFRP spikes. Fir wood is characterized by its low density, low compression strength, and high level of defects, and it is likely to distort when dried and tends to fail under tension due to the presence of cracks, knots, or grain deviation. The proposed repair technique consists of the insertion of BFRP spikes into timber beams to restore the continuity of cracked sections. The experimental efforts deal with the evaluation of the bending strength and deformation properties of 24 timber beams. An artificially simulated cracking was produced by cutting the wood beams in half or notching. The obtained results for the repaired beams were compared with those of solid undamaged and damaged beams, and increases of beam capacity, bending strength and of modulus of elasticity, and analysis of failure modes was discussed. For notched beams, the application of the BFRP spikes was able to restore the original bending capacity of undamaged beams, while only a small part of the original capacity was recovered for beams that were cut in half.

INNOVATIVE HYBRIDSIL POLY(SILOXANE IMIDE) COMPOSITE REPAIR MATERIALS AND METHODS, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Through the proposed STTR program, NanoSonic and Virginia Tech will create an innovative low viscosity, high Tg copolymer injection repair material and methodology...

Employing organizational modeling and simulation of the KC-135 depot's flight controls repair cell

OpenAIRE

Paskin, Matthew A.; Trevino, Alice W.; Ferrer, Geraldo; Dillard, John T.

2008-01-01

Today’s environment of increased operations tempo is stressing the KC- 135 Stratotanker fleet. With an 80-year life span expectancy, effectively maintaining these aircraft is challenging. This research modeled the KC- 135 programmed depot maintenance (PDM) flight controls repair cell to identify improvement opportunities within the repair process. Computational organizational modeling (COM) incorporates the human element along with organizational design theory. By employing ...

Hsp90: A New Player in DNA Repair?

Directory of Open Access Journals (Sweden)

Rosa Pennisi

2015-10-01

Full Text Available Heat shock protein 90 (Hsp90 is an evolutionary conserved molecular chaperone that, together with Hsp70 and co-chaperones makes up the Hsp90 chaperone machinery, stabilizing and activating more than 200 proteins, involved in protein homeostasis (i.e., proteostasis, transcriptional regulation, chromatin remodeling, and DNA repair. Cells respond to DNA damage by activating complex DNA damage response (DDR pathways that include: (i cell cycle arrest; (ii transcriptional and post-translational activation of a subset of genes, including those associated with DNA repair; and (iii triggering of programmed cell death. The efficacy of the DDR pathways is influenced by the nuclear levels of DNA repair proteins, which are regulated by balancing between protein synthesis and degradation as well as by nuclear import and export. The inability to respond properly to either DNA damage or to DNA repair leads to genetic instability, which in turn may enhance the rate of cancer development. Multiple components of the DNA double strand breaks repair machinery, including BRCA1, BRCA2, CHK1, DNA-PKcs, FANCA, and the MRE11/RAD50/NBN complex, have been described to be client proteins of Hsp90, which acts as a regulator of the diverse DDR pathways. Inhibition of Hsp90 actions leads to the altered localization and stabilization of DDR proteins after DNA damage and may represent a cell-specific and tumor-selective radiosensibilizer. Here, the role of Hsp90-dependent molecular mechanisms involved in cancer onset and in the maintenance of the genome integrity is discussed and highlighted.

Satisfaction, function and repair integrity after arthroscopic versus mini-open rotator cuff repair.

Science.gov (United States)

Barnes, L A Fink; Kim, H M; Caldwell, J-M; Buza, J; Ahmad, C S; Bigliani, L U; Levine, W N

2017-02-01

Advances in arthroscopic techniques for rotator cuff repair have made the mini-open approach less popular. However, the mini-open approach remains an important technique for repair for many surgeons. The aims of this study were to compare the integrity of the repair, the function of the shoulder and satisfaction post-operatively using these two techniques in patients aged > 50 years. We identified 22 patients treated with mini-open and 128 patients treated with arthroscopic rotator cuff repair of July 2007 and June 2011. The mean follow-up was two years (1 to 5). Outcome was assessed using the American Shoulder and Elbow Surgeons (ASES) and Simple Shoulder Test (SST) scores, and satisfaction. The integrity of the repair was assessed using ultrasonography. A power analysis ensured sufficient enrolment. There was no statistically significant difference between the age, function, satisfaction, or pain scores (p > 0.05) of the two groups. The integrity of the repair and the mean SST scores were significantly better in the mini-open group (91% of mini-open repairs were intact versus 60% of arthroscopic repairs, p = 0.023; mean SST score 10.9 (standard deviation (sd) 1.3) in the mini-open group; 8.9 (sd 3.5) in arthroscopic group; p = 0.003). The ASES scores were also higher in the mini-open group (mean ASES score 91.0 (sd 10.5) in mini-open group; mean 82.70 (sd 19.8) in the arthroscopic group; p = 0.048). The integrity of the repair and function of the shoulder were better after a mini-open repair than after arthroscopic repair of a rotator cuff tear in these patients. The functional difference did not translate into a difference in satisfaction. Mini-open rotator cuff repair remains a useful technique despite advances in arthroscopy. Cite this article: Bone Joint J 2017;99-B:245-9. ©2017 The British Editorial Society of Bone & Joint Surgery.

Immunochemical approach to the study of DNA repair. Proposed technical program and technical progress report

International Nuclear Information System (INIS)

1982-01-01

A simple immunochemical assay to quantify DNA lesions is being developed in order to facilitate the study of DNA repair. Antibodies have been raised to 5,6-dihydroxy-dihydrothymine and to thymine dimers and these have been used to measure DNA damages produced by osmium tetroxide and ultraviolet light, respectively. An enzyme immunoassay has been developed and the sensitivity of this method will be compared to physical, enzymatic, and chemical methods using PM2 bacteriophage DNA. Finally DNA repair will be assayed in several model systems

Peripherally Inserted Central Catheters in Pediatric Patients: To Repair or Not Repair

International Nuclear Information System (INIS)

Gnannt, Ralph; Patel, Premal; Temple, Michael; Al Brashdi, Yahya; Amaral, Joao; Parra, Dimitri; Rea, Vanessa; Stephens, Derek; Connolly, Bairbre

2017-01-01

IntroductionPreservation of venous access in children is a major concern in pediatric interventional radiology. If a peripherally inserted central catheter (PICC) breaks, there are two options: repair the line with a repair kit or exchange the line over a wire in the interventional suite. The purpose of this study is to assess the outcome of PICC repairs in children and to compare these with the outcomes of PICC exchange.Materials and MethodsThis is a single-center, retrospective study of central line-associated bloodstream infection (CLABSI) following management of externally broken PICCs (2010–2014). The occurrence of CLABSI within 30 days after repair (Group A) or exchange (Group B) of a line was analyzed, as well as PICCs exchanged following an initial and failed repair.ResultsA total of 235 PICC breaks were included in the study, of which 161 were repaired, and 116 of whom were successful (68%, Group A). No repair was performed in 74 PICCs—55/74 of these were exchanged over a wire (74%, Group B), and 19/74 lines were removed. The 30 days post-repair CLABSI rate (Group A) was 2.0 infections per 1000 catheter days, and the calculated risk was 4.3%. In comparison the 30 days post-exchange CLABSI rate (Group B) was 4.0 per 1000 catheter days and the calculated risk 10.9%. This difference was significant when adjusted for antibiotic use (OR 3.87; 95% CI 1.07–14.0, p = 0.039).ConclusionThe results of this study support repairing a broken PICC instead of removing or replacing the line.

Peripherally Inserted Central Catheters in Pediatric Patients: To Repair or Not Repair

Energy Technology Data Exchange (ETDEWEB)

Gnannt, Ralph, E-mail: ralph.gnannt@usz.ch; Patel, Premal; Temple, Michael; Al Brashdi, Yahya; Amaral, Joao; Parra, Dimitri; Rea, Vanessa [University of Toronto, Image Guided Therapy, Diagnostic Imaging, The Hospital for Sick Children (Canada); Stephens, Derek [University of Toronto, Child Health Evaluative Sciences (Canada); Connolly, Bairbre [University of Toronto, Image Guided Therapy, Diagnostic Imaging, The Hospital for Sick Children (Canada)

2017-06-15

IntroductionPreservation of venous access in children is a major concern in pediatric interventional radiology. If a peripherally inserted central catheter (PICC) breaks, there are two options: repair the line with a repair kit or exchange the line over a wire in the interventional suite. The purpose of this study is to assess the outcome of PICC repairs in children and to compare these with the outcomes of PICC exchange.Materials and MethodsThis is a single-center, retrospective study of central line-associated bloodstream infection (CLABSI) following management of externally broken PICCs (2010–2014). The occurrence of CLABSI within 30 days after repair (Group A) or exchange (Group B) of a line was analyzed, as well as PICCs exchanged following an initial and failed repair.ResultsA total of 235 PICC breaks were included in the study, of which 161 were repaired, and 116 of whom were successful (68%, Group A). No repair was performed in 74 PICCs—55/74 of these were exchanged over a wire (74%, Group B), and 19/74 lines were removed. The 30 days post-repair CLABSI rate (Group A) was 2.0 infections per 1000 catheter days, and the calculated risk was 4.3%. In comparison the 30 days post-exchange CLABSI rate (Group B) was 4.0 per 1000 catheter days and the calculated risk 10.9%. This difference was significant when adjusted for antibiotic use (OR 3.87; 95% CI 1.07–14.0, p = 0.039).ConclusionThe results of this study support repairing a broken PICC instead of removing or replacing the line.

Influence of repair length on residual stress in the repair weld of a clad plate

International Nuclear Information System (INIS)

Jiang Wenchun; Xu, X.P.; Gong, J.M.; Tu, S.T.

2012-01-01

Highlights: ► Residual stress in the repair weld of a stainless steel clad plate is investigated. ► The effect of repair length on residual stress has been studied. ► Large tensile residual stress is generated in the repair weld and heat affected zone. ► With the increase of repair length, transverse stress is decreased. ► Repair length has little effect on longitudinal stress. - Abstract: A 3-D sequential coupling finite element simulation is performed to investigate the temperature field and residual stress in the repair weld of a stainless steel clad plate. The effect of repair length on residual stress has been studied, aiming to provide a reference for repairing the cracked clad plate. The results show that large tensile residual stresses are generated in the repair weld and heat affected zone (HAZ), and then decrease gradually away from the weld and HAZ. The residual stresses through thickness in the clad layer are relative uniform, while they are non-uniform in the base metal. A discontinuous stress distribution is generated across the interface between weld metal and base metal. The repair length has a great effect on transverse stress. With the increase of repair length, the transverse stress is decreased. When the repair length is increased to 14 cm, the peak of transverse stress has been decreased below yield strength, and the transverse stress in the weld and HAZ has also been greatly decreased. But the repair length has little effect on longitudinal stress.

Integer goal programming approach for finding a compromise ...

African Journals Online (AJOL)

In second model the cost and time spent on repairing the components are considered as two different objectives. Selective maintenance operation is used to select the repairable components and a multi-objective goal programming algorithm is proposed to obtain compromise selection of repairable components for the two ...

Service water system repair/replacement guidelines: Planning and implementation

International Nuclear Information System (INIS)

Frederick, G.J.; Gandy, D.W.; Peterson, A.G. Jr.; Findlan, S.J.

1993-11-01

Service water system failures have prompted concerns related to extended power plant operating life and plant availability. Selection and procurement of materials for repair or replacement of piping and components may be the most important factors in improving service water system reliability. The authors examined factors that contribute to reduced SWS reliability. The factors include material selection inadequacies, water treatment problems, operational/maintenance practices, fabrication procedures, environmental degradation mechanisms, and coating problems. The authors investigated material selection for replacement and repair, taking into account fabrication practices, environmental concerns, and cost comparisons of materials. They examined specific components such as piping, pumps, valves, and heat exchangers with regard to material selection and fabrication practice. Although proper material selection is essential in upgrading and maintaining the designed functions of a SWS, it is critical to address SWS repair/replacement activities with a systemwide approach. Degradation of materials in SWS applications are plant specific, depending on factors unique to each site such as geographic location, existing materials, operating procedures, and environment. All these characteristics must be addressed in making repair/replacement decisions. Criteria that must be integrated for successful long-term operation of SWS include the following: Materials selection (upgrade or in-kind replacement), Evaluation of root cause or nature of the failure mechanism, Scope of the repair/replacement activities, Material compatibility of the existing materials, Operational and maintenance procedures, Code or jurisdictional requirements, Economic considerations, Water treatment programs, System design improvements or modifications

DNA repair deficiency in neurodegeneration

DEFF Research Database (Denmark)

Jeppesen, Dennis Kjølhede; Bohr, Vilhelm A; Stevnsner, Tinna V.

2011-01-01

Deficiency in repair of nuclear and mitochondrial DNA damage has been linked to several neurodegenerative disorders. Many recent experimental results indicate that the post-mitotic neurons are particularly prone to accumulation of unrepaired DNA lesions potentially leading to progressive...... neurodegeneration. Nucleotide excision repair is the cellular pathway responsible for removing helix-distorting DNA damage and deficiency in such repair is found in a number of diseases with neurodegenerative phenotypes, including Xeroderma Pigmentosum and Cockayne syndrome. The main pathway for repairing oxidative...... base lesions is base excision repair, and such repair is crucial for neurons given their high rates of oxygen metabolism. Mismatch repair corrects base mispairs generated during replication and evidence indicates that oxidative DNA damage can cause this pathway to expand trinucleotide repeats, thereby...

Improvement of adhesion performance of mortar-repair interface with inducing crack path into repair

Directory of Open Access Journals (Sweden)

A. Satoh

2015-10-01

Full Text Available The most important performance for repair materials is adhesion to the substrate. The authors experimentally find out that high modulus fine aggregates in repair material enhance strength of it as well as the strength of the interface repaired with it, compared to the ordinary repair without fine aggregates. This paper elaborates the mechanisms for that with fractographic observation and FEM analysis based on the results of experiment. Also the authors discuss the ways for enhancing the strength and ductility of the repaired mortar

Programmed Death Ligand 1 Expression Among 700 Consecutive Endometrial Cancers: Strong Association With Mismatch Repair Protein Deficiency.

Science.gov (United States)

Li, Zaibo; Joehlin-Price, Amy S; Rhoades, Jennifer; Ayoola-Adeola, Martins; Miller, Karin; Parwani, Anil V; Backes, Floor J; Felix, Ashley S; Suarez, Adrian A

2018-01-01

This study aims to determine the prevalence of programmed death ligand 1 (PD-L1) expression in endometrial carcinoma (EC) and determine clinical and pathological associations. Immunohistochemistry for PD-L1 was performed on sections of a triple-core tissue microarray of 700 ECs. Positive PD-L1 expression, defined as 1% of cells staining positive, was evaluated in tumor and stromal compartments. Using age-adjusted logistic regression, we estimated odds ratios and 95% confidence intervals for associations between PD-L1 expression (overall and by staining compartment) with clinical and tumor characteristics. Kaplan-Meier plots and log-rank tests were used to evaluate associations between PD-L1 expression and EC-specific survival. PD-L1 expression was observed in 100 cases (14.3%), including 27 (3.9%) with expression in tumor cells only, 35 (5.0%) with expression in both tumor cells and stroma, and 38 (5.4%) with expression in stroma only. Expression was observed in ECs of different histologic types. Tumors characterized by loss of mismatch repair proteins were significantly associated with tumoral PD-L1 expression (P < 0.0001), but not with stromal PD-L1 expression. Both tumoral and stromal PD-L1 expressions were associated with high-grade endometrioid histology, nonendometrioid histology, and lymphovascular space invasion. We observed no significant associations between PD-L1 expression and EC-specific survival. PD-L1 is expressed in a significant proportion of EC and is associated with mismatch repair deficiency, potentially representing a mechanism of tumor immune evasion and a therapeutic target in EC.

Radiobiological significance of DNA repair

International Nuclear Information System (INIS)

Kuzin, A.M.

1978-01-01

A short outline is given on the history of the problem relating to the repair of radiation injuries, specifically its molecular mechanisms. The most urgent problems which currently confront the researchers are noted. This is a further study on the role of DNA repair in post-radiation recovery, search for ways to activate and suppress DNA repair, investigations into the activity balance of various repair enzymes as well as the problem of errors in the structure of repairing DNA. An important role is attached to the investigations of DNA repair in solving a number of practical problems

DNA repair in neurons: So if they don't divide what's to repair?

International Nuclear Information System (INIS)

Fishel, Melissa L.; Vasko, Michael R.; Kelley, Mark R.

2007-01-01

Neuronal DNA repair remains one of the most exciting areas for investigation, particularly as a means to compare the DNA repair response in mitotic (cancer) vs. post-mitotic (neuronal) cells. In addition, the role of DNA repair in neuronal cell survival and response to aging and environmental insults is of particular interest. DNA damage caused by reactive oxygen species (ROS) such as generated by mitochondrial respiration includes altered bases, abasic sites, and single- and double-strand breaks which can be prevented by the DNA base excision repair (BER) pathway. Oxidative stress accumulates in the DNA of the human brain over time especially in the mitochondrial DNA (mtDNA) and is proposed to play a critical role in aging and in the pathogenesis of several neurological disorders including Parkinson's disease, ALS, and Alzheimer's diseases. Because DNA damage accumulates in the mtDNA more than nuclear DNA, there is increased interest in DNA repair pathways and the consequence of DNA damage in the mitochondria of neurons. The type of damage that is most likely to occur in neuronal cells is oxidative DNA damage which is primarily removed by the BER pathway. Following the notion that the bulk of neuronal DNA damage is acquired by oxidative DNA damage and ROS, the BER pathway is a likely area of focus for neuronal studies of DNA repair. BER variations in brain aging and pathology in various brain regions and tissues are presented. Therefore, the BER pathway is discussed in greater detail in this review than other repair pathways. Other repair pathways including direct reversal, nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination and non-homologous end joining are also discussed. Finally, there is a growing interest in the role that DNA repair pathways play in the clinical arena as they relate to the neurotoxicity and neuropathy associated with cancer treatments. Among the numerous side effects of cancer treatments, major clinical effects

Reward optimization of a repairable system

International Nuclear Information System (INIS)

Castro, I.T.; Perez-Ocon, R.

2006-01-01

This paper analyzes a system subject to repairable and non-repairable failures. Non-repairable failures lead to replacement of the system. Repairable failures, first lead to repair but they lead to replacement after a fixed number of repairs. Operating and repair times follow phase type distributions (PH-distributions) and the pattern of the operating times is modelled by a geometric process. In this context, the problem is to find the optimal number of repairs, which maximizes the long-run average reward per unit time. To this end, the optimal number is determined and it is obtained by efficient numerical procedures

Reward optimization of a repairable system

Energy Technology Data Exchange (ETDEWEB)

Castro, I.T. [Departamento de Matematicas, Facultad de Veterinaria, Universidad de Extremadura, Avenida de la Universidad, s/n. 10071 Caceres (Spain)]. E-mail: inmatorres@unex.es; Perez-Ocon, R. [Departamento de Estadistica e Investigacion Operativa, Facultad de Ciencias, Universidad de Granada, Avenida de Severo Ochoa, s/n. 18071 Granada (Spain)]. E-mail: rperezo@ugr.es

2006-03-15

This paper analyzes a system subject to repairable and non-repairable failures. Non-repairable failures lead to replacement of the system. Repairable failures, first lead to repair but they lead to replacement after a fixed number of repairs. Operating and repair times follow phase type distributions (PH-distributions) and the pattern of the operating times is modelled by a geometric process. In this context, the problem is to find the optimal number of repairs, which maximizes the long-run average reward per unit time. To this end, the optimal number is determined and it is obtained by efficient numerical procedures.

Retinal detachment repair

Science.gov (United States)

... medicines Problems breathing You may not recover full vision. ... detachments can be repaired. Failure to repair the retina always results in loss of vision to some degree. After surgery, the quality of ...

A new incomplete-repair model based on a ''reciprocal-time'' pattern of sublethal damage repair

International Nuclear Information System (INIS)

Dale, R.G.; Fowler, J.F.

1999-01-01

A radiobiological model for closely spaced non-instantaneous radiation fractions is presented, based on the premise that the time process of sublethal damage (SLD) repair is 'reciprocal-time' (second order), rather than exponential (first order), in form. The initial clinical implications of such an incomplete-repair model are assessed. A previously derived linear-quadratic-based model was revised to take account of the possibility that SLD may repair with time such that the fraction of an element of initial damage remaining at time t is given as 1/(1+zt), where z is an appropriate rate constant; z is the reciprocal of the first half-time (τ) of repair. The general equation so derived for incomplete repair is applicable to all types of radiotherapy delivered at high, low and medium dose-rate in fractions delivered at regular time intervals. The model allows both the fraction duration and interfraction intervals to vary between zero and infinity. For any given value of z, reciprocal repair is associated with an apparent 'slowing-down' in the SLD repair rate as treatment proceeds. The instantaneous repair rates are not directly governed by total dose or dose per fraction, but are influenced by the treatment duration and individual fraction duration. Instantaneous repair rates of SLD appear to be slower towards the end of a continuous treatment, and are also slower following 'long' fractions than they are following 'short' fractions. The new model, with its single repair-rate parameter, is shown to be capable of providing a degree of quantitative explanation for some enigmas that have been encountered in clinical studies. A single-component reciprocal repair process provides an alternative explanation for the apparent existence of a range of repair rates in human tissues, and which have hitherto been explained by postulating the existence of a multi-exponential repair process. The build-up of SLD over extended treatments is greater than would be inferred using a

CrowdAidRepair: A Crowd-Aided Interactive Data Repairing Method

KAUST Repository

Zhou, Jian; Li, Zhixu; Gu, Binbin; Xie, Qing; Zhu, Jia; Zhang, Xiangliang; Li, Guoliang

2016-01-01

turn to use the power of crowd in data repairing, but the crowd power has its own drawbacks such as high human intervention cost and inevitable low efficiency. In this paper, we propose a crowd-aided interactive data repairing method which takes

Complex networks under dynamic repair model

Science.gov (United States)

Chaoqi, Fu; Ying, Wang; Kun, Zhao; Yangjun, Gao

2018-01-01

Invulnerability is not the only factor of importance when considering complex networks' security. It is also critical to have an effective and reasonable repair strategy. Existing research on network repair is confined to the static model. The dynamic model makes better use of the redundant capacity of repaired nodes and repairs the damaged network more efficiently than the static model; however, the dynamic repair model is complex and polytropic. In this paper, we construct a dynamic repair model and systematically describe the energy-transfer relationships between nodes in the repair process of the failure network. Nodes are divided into three types, corresponding to three structures. We find that the strong coupling structure is responsible for secondary failure of the repaired nodes and propose an algorithm that can select the most suitable targets (nodes or links) to repair the failure network with minimal cost. Two types of repair strategies are identified, with different effects under the two energy-transfer rules. The research results enable a more flexible approach to network repair.

Simulation based mask defect repair verification and disposition

Science.gov (United States)

Guo, Eric; Zhao, Shirley; Zhang, Skin; Qian, Sandy; Cheng, Guojie; Vikram, Abhishek; Li, Ling; Chen, Ye; Hsiang, Chingyun; Zhang, Gary; Su, Bo

2009-10-01

As the industry moves towards sub-65nm technology nodes, the mask inspection, with increased sensitivity and shrinking critical defect size, catches more and more nuisance and false defects. Increased defect counts pose great challenges in the post inspection defect classification and disposition: which defect is real defect, and among the real defects, which defect should be repaired and how to verify the post-repair defects. In this paper, we address the challenges in mask defect verification and disposition, in particular, in post repair defect verification by an efficient methodology, using SEM mask defect images, and optical inspection mask defects images (only for verification of phase and transmission related defects). We will demonstrate the flow using programmed mask defects in sub-65nm technology node design. In total 20 types of defects were designed including defects found in typical real circuit environments with 30 different sizes designed for each type. The SEM image was taken for each programmed defect after the test mask was made. Selected defects were repaired and SEM images from the test mask were taken again. Wafers were printed with the test mask before and after repair as defect printability references. A software tool SMDD-Simulation based Mask Defect Disposition-has been used in this study. The software is used to extract edges from the mask SEM images and convert them into polygons to save in GDSII format. Then, the converted polygons from the SEM images were filled with the correct tone to form mask patterns and were merged back into the original GDSII design file. This merge is for the purpose of contour simulation-since normally the SEM images cover only small area (~1 μm) and accurate simulation requires including larger area of optical proximity effect. With lithography process model, the resist contour of area of interest (AOI-the area surrounding a mask defect) can be simulated. If such complicated model is not available, a simple

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

Science.gov (United States)

2010-10-01

... repair, equipment damaged, dismantling retired property, fringe benefits, other casualties and insurance, lease rentals, joint facility rents, other rents, depreciation, joint facility, repairs billed to others... maintenance, machinery repair, equipment damaged, dismantling retired property, fringe benefits, other...

Collision Repair Campaign

Science.gov (United States)

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

Repair mechanisms and exposure standards

International Nuclear Information System (INIS)

Mills, W.A.

1978-01-01

The following topics are discussed; public policy for setting radiation standards; use of linear, nonthreshold theory in setting radiation standards; dose-rate dependence; occupational exposure to radiation; radon inhalation from radium in the soil in the vicinity of the phosphate industry; relation of repair mechanisms for cell survival to cancer induction; application of information on genetic repair to humans and to cancer induction; importance of repair processes in radiation protection standards; corrective factors for repair processes; relation of repair processes to age, sex, and other factors; and population distribution in radiosensitivity

Laparoscopic repair of postoperative perineal hernia.

LENUS (Irish Health Repository)

Ryan, Stephen

2010-01-01

Perineal hernias are infrequent complications following abdominoperineal operations. Various approaches have been described for repair of perineal hernias including open transabdominal, transperineal or combined abdominoperineal repairs. The use of laparoscopic transabdominal repair of perineal hernias is not well-described. We present a case report demonstrating the benefits of laparoscopic repair of perineal hernia following previous laparoscopic abdominoperineal resection (APR) using a nonabsorbable mesh to repair the defect. We have demonstrated that the use of laparoscopy with repair of the pelvic floor defect using a non absorbable synthetic mesh offers an excellent alternative with many potential advantages over open transabdominal and transperineal repairs.

Transfer of Chinese hamster DNA repair gene(s) into repair-deficient human cells (Xeroderma pigmentosum)

International Nuclear Information System (INIS)

Karentz, D.; Cleaver, J.E.

1985-01-01

Transfer of repair genes by DNA transfection into repair-deficient Xeroderma pigmentosum (XP) cells has thus far been unsuccessful, presenting an obstacle to cloning XP genes. The authors chose an indirect route to transfer repair genes in chromosome fragments. DNA repair-competent (UV resistant) hybrid cell lines were established by PEG-mediated fusions of DNA repair-deficient (UV sensitive) human fibroblasts (XP12RO) with wild type Chinese hamster (CHO) cells (AA8). CHO cells were exposed to 5 Krad X-rays prior to fusions, predisposing hybrid cells to lose CHO chromosome fragments preferentially. Repair-competent hybrids were selected by periodic exposures to UV light. Secondary and tertiary hybrid cell lines were developed by fusion of X-irradiated hybrids to XP12RO. The hybrid cell lines exhibit resistance to UV that is comparable to that of CHO cells and they are proficient at repair replication after UV exposure. Whole cell DNA-DNA hybridizations indicate that the hybrids have greater homology to CHO DNA than is evident between XP12RO and CHO. These observations indicate that CHO DNA sequences which can function in repair of UV-damaged DNA in human cells have been transferred into the genome of the repair-deficient XP12RO cells

Generic and Automated Runtime Program Repair

Science.gov (United States)

2012-09-01

embedded systems, instead targeting desktop client software such as Firefox [63, 64], server software such as MySQL [63] or webservers [21], or design-by...server php 1,046,000 8,471 44 web programming python 407,000 355 11 general coding wireshark 2,814,000 63 7 packet analyzer total 5,139,000 10,193 105...0.25 php 28 / 44 13.00 8.80 1.84 0.62 python 1 / 11 13.00 8.80 1.22 0.16 wireshark 1 / 7 13.00 8.80 1.23 0.17 total 55 / 105 11.22h 1.60h 4.1.1. Program

Transperitoneal versus retroperitoneal approach for open abdominal aortic aneurysm repair in the targeted vascular National Surgical Quality Improvement Program

NARCIS (Netherlands)

Buck, Dominique B.; Ultee, Klaas H J; Zettervall, Sara L.; Soden, Pete A.; Darling, Jeremy; Wyers, Mark; van Herwaarden, Joost A.; Schermerhorn, Marc L.

Objective: We sought to compare current practices in patient selection and 30-day outcomes for transperitoneal and retroperitoneal abdominal aortic aneurysm (AAA) repairs. Methods: All patients undergoing elective transperitoneal or retroperitoneal surgical repair for AAA between January 2011 and

Aging and DNA repair capability. [Review

Energy Technology Data Exchange (ETDEWEB)

Tice, R R

1977-01-01

A review of the literature on DNA repair processes in relation to aging is presented under the following headings: DNA repair processes; age-related occurrence of unrepaired DNA lesions; DNA repair capability as a function of age; tissue-specific DNA repair capability; acceleration of the aging process by exposure to DNA damaging agents; human genetic syndromes; and longevity and DNA repair processes. (HLW)

Repair of UV-irradiated plasmid DNA in excision repair deficient mutants of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Ikai, K.; Tano, K.; Ohnishi, T.; Nozu, K.

1985-01-01

The repair of UV-irradiated DNA of plasmid YEp13 was studied in the incision defective strains by measurement of cell transformation frequency. In Saccharomyces cerevisiae, rad1,2,3 and 4 mutants could repair UV-damaged plasmid DNA. In Escherichia coli, uvrA mutant was unable to repair UV-damaged plasmid DNA; however, pretreatment of the plasmid with Micrococcus luteus endonuclease increased repair. It was concluded that all the mutations of yeast were probably limited only to the nuclear DNA. (author)

A hypothesis: factor VII governs clot formation, tissue repair and apoptosis.

Science.gov (United States)

Coleman, Lewis S

2007-01-01

A hypothesis: thrombin is a "Universal Enzyme of Energy Transduction" that employs ATP energy in flowing blood to activate biochemical reactions and cell effects in both hemostasis and tissue repair. All cells possess PAR-1 (thrombin) receptors and are affected by thrombin elevations, and thrombin effects on individual cell types are determined by their unique complement of PAR-1 receptors. Disruption of the vascular endothelium (VE) activates a tissue repair mechanism (TRM) consisting of the VE, tissue factor (TF), and circulating Factors VII, IX and X that governs localized thrombin elevations to activate clot formation and cellular effects that repair tissue damage. The culmination of the repair process occurs with the restoration of the VE followed by declines in thrombin production that causes Apoptosis ("programmed cell death") in wound-healing fibroblasts, which functions as a mechanism to draw wound edges together. The location and magnitude of TRM activity governs the location and magnitude of Factor VIII activity and clot formation, but the large size of Factor VIII prevents it from penetrating the clot formed by its activity, so that its effects are self-limiting. Factors VII, IX and X function primarily as tissue repair enzymes, while Factor VIII and Factor XIII are the only serine protease enzymes in the "Coagulation Cascade" that are exclusively associated with hemostasis.

DNA repair in Mycobacterium tuberculosis revisited.

Science.gov (United States)

Dos Vultos, Tiago; Mestre, Olga; Tonjum, Tone; Gicquel, Brigitte

2009-05-01

Our understanding of Mycobacterium tuberculosis DNA repair mechanisms is still poor compared with that of other bacterial organisms. However, the publication of the first complete M. tuberculosis genome sequence 10 years ago boosted the study of DNA repair systems in this organism. A first step in the elucidation of M. tuberculosis DNA repair mechanisms was taken by Mizrahi and Andersen, who identified homologs of genes involved in the reversal or repair of DNA damage in Escherichia coli and related organisms. Genes required for nucleotide excision repair, base excision repair, recombination, and SOS repair and mutagenesis were identified. Notably, no homologs of genes involved in mismatch repair were identified. Novel characteristics of the M. tuberculosis DNA repair machinery have been found over the last decade, such as nonhomologous end joining, the presence of Mpg, ERCC3 and Hlr - proteins previously presumed to be produced exclusively in mammalian cells - and the recently discovered bifunctional dCTP deaminase:dUTPase. The study of these systems is important to develop therapeutic agents that can counteract M. tuberculosis evolutionary changes and to prevent adaptive events resulting in antibiotic resistance. This review summarizes our current understanding of the M. tuberculosis DNA repair system.

Repair-modification of radiodamaged genes

International Nuclear Information System (INIS)

Volpe, P.; Institute of Experimental Medicine, Rome; Eremenko, T.

1995-01-01

It is proposed that through repair-modification, the modified base 5mC may have facilitated the divergent evolution of coding (hypomethylated exon) and uncoding (hypermethylated promoter and intron) sequences in eukaryotic genes. The radioinduced repair patches appearing in regions lacking 5mC are fully reconstructed by excision-repair, whereas those appearing in regions containing 5mC are incompletely reconstructed by this conventional mechanism. Such a second class of repair patches may, however, become fully reconstructed, in the S phase, by repair-modification. In fact, while DNA polymerase β - which is a key enzyme of excision-repair - is active through the whole interphase. DNA methylase - which is responsible for post-synthetic DNA modification - is essentially active in S. Uncoupling of these two enzyme systems, outside S, might explain why in unsynchronised cells repair patches of non-replicating strands are hypomethylated when compared with specific methylation of replicating strands. In other words, excision-repair would always be able to re-establish the primary ATGC language of both damaged unmethylated and methylated regions, while repair-modification would be able to re-establish the modified ATGC(5mC) language of the damaged methylated regions, only in S, but not in G 1 or G 2 . In these two phases, when DNA methylation is inversely correlated with pre-mRNA transcription (as in the case of many tissue-specific genes), such demethylation might induce a silent transcriptional unit to become active. (Author)

Maintenance and repair of LMFBR steam generators

International Nuclear Information System (INIS)

Verriere, P.; Alanche, J.; Minguet, J.L.

1984-06-01

After some general remarks on the French fast neutron system, this paper presents the state of the program for the construction of fast reactor in France. Then, the general design of Super Phenix 1 steam generator components is outlined and, the in-service monitoring systems and protective devices with which they are equiped are briefly described. The methods used, in the event of leakage, for leak location, steam generator inspection, steam generator repair and putting the affected loop back into service, are discussed. There are two main lines of research, relating respectively to the means of water leak detection in sodium and the inspection arrangements that will be used either periodically, or following a sodium-water reaction. Finally, after a brief description of the steam generator, this paper describes the four incidents (leaks) that occurred on the Phenix steam generator in the course of 1982 and 1983, and the subsequent repair operations

Repair promoted by plasmid pKM101 is different from SOS repair

International Nuclear Information System (INIS)

Goze, A.; Devoret, R.

1979-01-01

In E. coli K12 bacteria carrying plasmid pKM101, prophage lambda was induced at UV doses higher than in plasmid-less parental bacteria. UV-induced reactivation per se was less effective. Bacteria with pKM101 showed no alteration in their division cycle. Plasmid PKM101 coded for a constitutive error-prone repair different from the inducible error-prone repair called SOS repair. Plasmid pKM101 protected E. coli bacteria from UV damage but slightly sensitized them to X-ray lesions. Protection against UV damage was effective in mutant bacteria deficient in DNA excision-repair provided that the recA, lexA and uvrE genes were functional. Survival of phages lambda and S13 after UV irradiation was enhanced in bacteria carrying plasmid pKM101; phage lambda mutagenesis was also increased. Plasmid pKM101 repaired potentially lethal DNA lesions, although Wild-type DNA sequences may not necessarily be restored; hence the mutations observed are the traces of the original DNA lesions. (Auth.)

Draft environmental statement related to steam-generator repair at Point Beach Nuclear Plant, Unit No. 1. Docket No. 50-266

International Nuclear Information System (INIS)

1983-07-01

The staff has considered the environmental impacts and economic costs of the proposed steam generator repair at the Point Beach Nuclear Plant Unit No. 1 along with reasonable alternatives to the proposed action. The staff has concluded that the proposed repair will not significantly affect the quality of the human environment and that there are no preferable alternatives to the proposed action. Furthermore, any impacts from the repair program are outweighed by its benefits

Final environmental statement related to steam-generator repair at Point Beach Nuclear Plant, Unit No. 1 (Docket No. 50-266)

International Nuclear Information System (INIS)

1983-09-01

The staff hhas considered the environental impacts and economic costs of the proposed steam generator repair at the Point Beach Nuclear Plant, Unit No. 1 along with reasonable alternatives to the proposed action. The staff has concluded that the proposed repair will not significantly affect the quality of the human environment and that there are no preferable alternatives to the proposed action. Furthermore, any impacts from the repair program are outweighed by its benefits

The role of a certified calibration laboratory in a station's measuring and test equipment calibration, repair, and documentation program

International Nuclear Information System (INIS)

Ebenstreit, K.; MacIntosh, N.

1995-01-01

This paper outlines the role of a Certified Calibration Laboratory in- ensuring that the requirements of Measuring and Test Equipment calibration, identification, and traceability are met and documented. The Nuclear environment is one which is subject to influences from numerous 'quality agents'. One of the fields which comes under the scrutiny of the quality agents is that of equipment calibration and repair (both field components and M and TE). There is a responsibility to produce a superior product for the Ontario Consumer. The maintenance and calibration of Station Systems and their components have a direct impact on this output. The Measuring and Test Equipment element in each of these needs can be addressed by having a defined group of Maintenance Staff to execute a Measuring and Test Equipment Program which meets specific parameters. (author)

Cleft lip and palate repair

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/002979.htm Cleft lip and palate repair To use the sharing features on this ... Cheiloplasty; Cleft rhinoplasty; Palatoplasty; Tip rhinoplasty Patient Instructions Cleft lip and palate repair - discharge Images Cleft lip repair - series References ...

'Regular' and 'emergency' repair

International Nuclear Information System (INIS)

Luchnik, N.V.

1975-01-01

Experiments on the combined action of radiation and a DNA inhibitor using Crepis roots and on split-dose irradiation of human lymphocytes lead to the conclusion that there are two types of repair. The 'regular' repair takes place twice in each mitotic cycle and ensures the maintenance of genetic stability. The 'emergency' repair is induced at all stages of the mitotic cycle by high levels of injury. (author)

Current practices of laparoscopic inguinal hernia repair: a population-based analysis.

Science.gov (United States)

Trevisonno, M; Kaneva, P; Watanabe, Y; Fried, G M; Feldman, L S; Andalib, A; Vassiliou, M C

2015-10-01

The selection of a laparoscopic approach for inguinal hernias varies among surgeons. It is unclear what is being done in actual practice. The purpose of this study was to report practice patterns for treatment of inguinal hernias among Quebec surgeons, and to identify factors that may be associated with the choice of operative approach. We studied a population-based cohort of patients who underwent an inguinal hernia repair between 2007 and 2011 in Quebec, Canada. A generalized linear model was used to identify predictors associated with the selection of a laparoscopic approach. 49,657 inguinal hernias were repaired by 478 surgeons. Laparoscopic inguinal hernia repair (LIHR) was used in 8 % of all cases. LIHR was used to repair 28 % of bilateral hernias, 10 % of recurrent hernias, 6 % of unilateral hernias, and 4 % of incarcerated hernias. 268 (56 %) surgeons did not perform any laparoscopic repairs, and 11 (2 %) surgeons performed more than 100 repairs. These 11 surgeons performed 61 % of all laparoscopic cases. Patient factors significantly associated with having LIHR included younger age, fewer comorbidities, bilateral hernias, and recurrent hernias. An open approach is favored for all clinical scenarios, even for situations where published guidelines recommend a laparoscopic approach. Surgeons remain divided on the best technique for inguinal hernia repair: while more than half never perform LIHR, the small proportion who perform many use the technique for a large proportion of their cases. There appears to be a gap between the best practices put forth in guidelines and what surgeons are doing in actual practice. Identification of barriers to the broader uptake of LIHR may help inform the design of educational programs to train those who have the desire to offer this technique for certain cases, and have the volume to overcome the learning curve.

Mechanical and mechanobiological influences on bone fracture repair : identifying important cellular characteristics

NARCIS (Netherlands)

Isaksson, H.E.

2007-01-01

Fracture repair is a complex and multifactorial process, which involves a well-programmed series of cellular and molecular events that result in a combination of intramembranous and endochondral bone formation. The vast majority of fractures is treated successfully. They heal through ‘secondary

When is cartilage repair successful?

International Nuclear Information System (INIS)

Raudner, M.; Roehrich, S.; Zalaudek, M.; Trattnig, S.; Schreiner, M.M.

2017-01-01

Focal cartilage lesions are a cause of long-term disability and morbidity. After cartilage repair, it is crucial to evaluate long-term progression or failure in a reproducible, standardized manner. This article provides an overview of the different cartilage repair procedures and important characteristics to look for in cartilage repair imaging. Specifics and pitfalls are pointed out alongside general aspects. After successful cartilage repair, a complete, but not hypertrophic filling of the defect is the primary criterion of treatment success. The repair tissue should also be completely integrated to the surrounding native cartilage. After some months, the transplants signal should be isointense compared to native cartilage. Complications like osteophytes, subchondral defects, cysts, adhesion and chronic bone marrow edema or joint effusion are common and have to be observed via follow-up. Radiological evaluation and interpretation of postoperative changes should always take the repair method into account. (orig.) [de

Betonreparationers holdbarhed (Durability of Concrete Repairs)

DEFF Research Database (Denmark)

Brimnes, Eydbjørn; Dali, Bogi í; Larsen, Erik Stoklund

1999-01-01

Concrete repairs on 11 pillars on bridges built in the sixties and repaired 8 to 9 years ago have been examined. Especially the chloride penetration in the repair concrete have been measured. Chloride penetration in the repair concrete is much lower than in the original concrete....

Meniscal repair devices.

Science.gov (United States)

Barber, F A; Herbert, M A

2000-09-01

Meniscal repair devices not requiring accessory incisions are attractive. Many factors contribute to their clinical effectiveness including their biomechanical characteristics. This study compared several new meniscal repair devices with standard meniscal suture techniques. Using a porcine model, axis-of-insertion loads were applied to various meniscal sutures and repair devices. A single device or stitch was placed in a created meniscal tear and a load applied. Both loads and modes of failure were recorded. The load-to-failure data show stratification into 4 distinct statistical groups. Group A, 113 N for a double vertical stitch; group B, 80 N for a single vertical stitch; group C, 57 N for the BioStinger, 56 N for a horizontal mattress stitch, and 50 N for the T-Fix stitch; and group D, 33 N for the Meniscus Arrow (inserted by hand or gun), 32 N for the Clearfix screw, 31 N for the SDsorb staple, 30 N for the Mitek meniscal repair system, and 27 N for the Biomet staple. The failure mechanism varied. Sutures broke away from the knot. The Meniscus Arrow and BioStinger pulled through the inner rim with the crossbar intact. The Clearfix screw failed by multiple mechanisms, whereas 1 leg of the SDsorb staple always pulled out of the outer rim. The Mitek device usually failed by pullout from the inner rim. The Biomet staple always broke at the crosshead or just below it. Although the surgeon should be aware of the material properties of the repair technique chosen for a meniscal repair, this information is only an indication of device performance and may not correlate with clinical healing results.

Residual stress by repair welds

International Nuclear Information System (INIS)

Mochizuki, Masahito; Toyoda, Masao

2003-01-01

Residual stress by repair welds is computed using the thermal elastic-plastic analysis with phase-transformation effect. Coupling phenomena of temperature, microstructure, and stress-strain fields are simulated in the finite-element analysis. Weld bond of a plate butt-welded joint is gouged and then deposited by weld metal in repair process. Heat source is synchronously moved with the deposition of the finite-element as the weld deposition. Microstructure is considered by using CCT diagram and the transformation behavior in the repair weld is also simulated. The effects of initial stress, heat input, and weld length on residual stress distribution are studied from the organic results of numerical analysis. Initial residual stress before repair weld has no influence on the residual stress after repair treatment near weld metal, because the initial stress near weld metal releases due to high temperature of repair weld and then stress by repair weld regenerates. Heat input has an effect for residual stress distribution, for not its magnitude but distribution zone. Weld length should be considered reducing the magnitude of residual stress in the edge of weld bead; short bead induces high tensile residual stress. (author)

Biomechanical Analysis of an Arthroscopic Broström Ankle Ligament Repair and a Suture Anchor-Augmented Repair.

Science.gov (United States)

Giza, Eric; Whitlow, Scott R; Williams, Brady T; Acevedo, Jorge I; Mangone, Peter G; Haytmanek, C Thomas; Curry, Eugene E; Turnbull, Travis Lee; LaPrade, Robert F; Wijdicks, Coen A; Clanton, Thomas O

2015-07-01

Secondary surgical repair of ankle ligaments is often indicated in cases of chronic lateral ankle instability. Recently, arthroscopic Broström techniques have been described, but biomechanical information is limited. The purpose of the present study was to analyze the biomechanical properties of an arthroscopic Broström repair and augmented repair with a proximally placed suture anchor. It was hypothesized that the arthroscopic Broström repairs would compare favorably to open techniques and that augmentation would increase the mean repair strength at time zero. Twenty (10 matched pairs) fresh-frozen foot and ankle cadaveric specimens were obtained. After sectioning of the lateral ankle ligaments, an arthroscopic Broström procedure was performed on each ankle using two 3.0-mm suture anchors with #0 braided polyethylene/polyester multifilament sutures. One specimen from each pair was augmented with a 2.9-mm suture anchor placed 3 cm proximal to the inferior tip of the lateral malleolus. Repairs were isolated and positioned in 20 degrees of inversion and 10 degrees of plantarflexion and loaded to failure using a dynamic tensile testing machine. Maximum load (N), stiffness (N/mm), and displacement at maximum load (mm) were recorded. There were no significant differences between standard arthroscopic repairs and the augmented repairs for mean maximum load and stiffness (154.4 ± 60.3 N, 9.8 ± 2.6 N/mm vs 194.2 ± 157.7 N, 10.5 ± 4.7 N/mm, P = .222, P = .685). Repair augmentation did not confer a significantly higher mean strength or stiffness at time zero. Mean strength and stiffness for the arthroscopic Broström repair compared favorably with previous similarly tested open repair and reconstruction methods, validating the clinical feasibility of an arthroscopic repair. However, augmentation with an additional proximal suture anchor did not significantly strengthen the repair. © The Author(s) 2015.

The time course of repair of ultraviolet-induced DNA damage; implications for the structural organization of repair

International Nuclear Information System (INIS)

Collins, A.; Squires, S.

1986-01-01

Alternative molecular mechanisms can be envisaged for the cellular repair of UV-damaged DNA. In the 'random collision' model, DNA damage distributed throughout the genome is recognised and repaired by a process of random collision between DNA damage and repair enzymes. The other model assumes a 'processive' mechanism, whereby DNA is scanned for damage by a repair complex moving steadily along its length. Random collision should result in a declining rate of repair with time as the concentration of lesions in the DNA falls; but the processive model predicts a constant rate until scanning is complete. The authors have examined the time course of DNA repair in human fibroblasts given low doses of UV light. Using 3 distinct assays, the authors find no sign of a constant repair rate after 4 J/m 2 or less, even when the first few hours after irradiation are examined. Thus DNA repair is likely to depend on random collision. (Auth.)

A biomechanical evaluation of all-inside 2-stitch meniscal repair devices with matched inside-out suture repair.

Science.gov (United States)

Ramappa, Arun J; Chen, Alvin; Hertz, Benjamin; Wexler, Michael; Grimaldi Bournissaint, Leandro; DeAngelis, Joseph P; Nazarian, Ara

2014-01-01

Many all-inside suture-based devices are currently available, including the Meniscal Cinch, FasT-Fix, Ultra FasT-Fix, RapidLoc, MaxFire, and CrossFix System. These different devices have been compared in various configurations, but to our knowledge, the Sequent meniscal repair device, which applies running sutures, has not been compared with the Ultra FasT-Fix, nor has it been compared with its suture, No. 0 Hi-Fi, using an inside-out repair technique. To assess the quality of the meniscal repair, all new devices should be compared with the gold standard: the inside-out repair. To that end, this study aims to compare the biomechanical characteristics of running sutures delivered by the Sequent meniscal repair device with 2 vertical mattress sutures applied using the Ultra FasT-Fix device and with 2 vertical mattress sutures using an inside-out repair technique with No. 0 Hi-Fi suture. Controlled laboratory study. Paired (medial and lateral), fresh-frozen porcine menisci were randomly assigned to 1 of 3 groups: Sequent (n = 17), Ultra FasT-Fix (n = 19), and No. 0 Hi-Fi inside-out repair (n = 20). Bucket-handle tears were created in all menisci and were subjected to repair according to their grouping. Once repaired, the specimens were subjected to cyclic loading (100, 300, and 500 cycles), followed by loading to failure. The Sequent and Ultra FasT-Fix device repairs and the suture repair exhibited low initial displacements. The Sequent meniscal repair device demonstrated the lowest displacement in response to cyclic loading. No. 0 Hi-Fi suture yielded the highest load to failure. With the development of the next generation of all-inside meniscal repair devices, surgeons may use these findings to select the method best suited for their patients. The Sequent meniscal repair device displays the least amount of displacement during cyclic loading but has a similar failure load to other devices.

The journey of DNA repair.

Science.gov (United States)

Saini, Natalie

2015-12-01

21 years ago, the DNA Repair Enzyme was declared "Molecule of the Year". Today, we are celebrating another "year of repair", with the 2015 Nobel Prize in Chemistry being awarded to Aziz Sancar, Tomas Lindahl and Paul Modrich for their collective work on the different DNA repair pathways.

Thymus repair compared with hemopoiesis repair in spleen after protracted irradiation

International Nuclear Information System (INIS)

Mackova, N.

1987-01-01

Matured female mice of ICR strain were irradiated from a 60 Co source with a daily dose rate of 5 Gy till total accumulated dose of 10 Gy for 2 days. Animals were examined in various intervals within 42 days after irradiation. The results revealed that protracted irradiation will induce a massive injury to hemopoiesis. The first repair processes occurred in thymus and were characterized by two phases. The first repair wave peaked about the day 10 and the second about the day 30 after irradiation. The repair processes observed in the red pulp of the spleen reached their highest intensity approximately between the days 14-16 after irradiation. (author)

Laparoscopic totally extraperitoneal inguinal hernia repair: lessons learned from 3,100 hernia repairs over 15 years.

Science.gov (United States)

Dulucq, Jean-Louis; Wintringer, Pascal; Mahajna, Ahmad

2009-03-01

Two revolutions in inguinal hernia repair surgery have occurred during the last two decades. The first was the introduction of tension-free hernia repair by Liechtenstein in 1989 and the second was the application of laparoscopic surgery to the treatment of inguinal hernia in the early 1990s. The purposes of this study were to assess the safety and effectiveness of laparoscopic totally extraperitoneal (TEP) repair and to discuss the technical changes that we faced on the basis of our accumulative experience. Patients who underwent an elective inguinal hernia repair at the Department of Abdominal Surgery at the Institute of Laparoscopic Surgery (ILS), Bordeaux, between June 1990 and May 2005 were enrolled retrospectively in this study. Patient demographic data, operative and postoperative course, and outpatient follow-up were studied. A total of 3,100 hernia repairs were included in the study. The majority of the hernias were repaired by TEP technique; the repair was done by transabdominal preperitoneal (TAPP) repair in only 3%. Eleven percent of the hernias were recurrences after conventional repair. Mean operative time was 17 min in unilateral hernia and 24 min in bilateral hernia. There were 36 hernias (1.2%) that required conversion: 12 hernias were converted to open anterior Liechtenstein and 24 to laparoscopic TAPP technique. The incidence of intraoperative complications was low. Most of the patients were discharged at the second day of the surgery. The overall postoperative morbidity rate was 2.2%. The incidence of recurrence rate was 0.35%. The recurrence rate for the first 200 repairs was 2.5%, but it decreased to 0.47% for the subsequent 1,254 hernia repairs According to our experience, in the hands of experienced laparoscopic surgeons, laparoscopic hernia repair seems to be the favored approach for most types of inguinal hernias. TEP is preferred over TAPP as the peritoneum is not violated and there are fewer intra-abdominal complications.

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

Energy Technology Data Exchange (ETDEWEB)

Darr, Paul S. [US Department of Energy, Washington, DC (United States). Office of Legacy Management

2016-01-01

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

40 CFR 63.1024 - Leak repair.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Leak repair. 63.1024 Section 63.1024... Standards for Equipment Leaks-Control Level 2 Standards § 63.1024 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected as soon as practical, but not later than 15 calendar...

Evaluation of Repair Tension in Arthroscopic Rotator Cuff Repair: Does It Really Matter to the Integrity of the Rotator Cuff?

Science.gov (United States)

Kim, Do Hoon; Jang, Young Hoon; Choi, Young Eun; Lee, Hwa-Ryeong; Kim, Sae Hoon

2016-11-01

Repair tension of a torn rotator cuff can affect healing after repair. However, a measurement of the actual tension during arthroscopic rotator cuff repair is not feasible. The relationship between repair tension and healing of a rotator cuff repair remains unclear. The purpose of this study was to evaluate the effect of repair tension on healing at the repair site. The hypothesis was that repair tension would be a major factor in determining the anatomic outcome of rotator cuff repair. Cohort study; Level of evidence, 2. Arthroscopic rotator cuff repairs (132 patients) for full-thickness rotator cuff tears were analyzed. An intraoperative model was designed for the estimation of repair tension using a tensiometer. Magnetic resonance imaging (MRI) was performed approximately 1 year (mean [±SD], 12.7 ± 3.2 months) postoperatively for the evaluation of healing at the repair site. Multivariable analysis was performed for tear size, amount of retraction, and fatty degeneration (FD) of rotator cuff muscles. The mean repair tension measured during the arthroscopic procedure was 28.5 ± 23.1 N. There was a statistically significant correlation between tension and tear size (Pearson correlation coefficient [PCC], 0.529; P repair tension also showed a significant inverse correlation with healing at the repair site (SCC, 0.195; P = .025). However, when sex, age, tear size, amount of retraction, tendon quality, and FD of rotator cuff muscles were included for multivariable logistic regression analysis, only FD of the infraspinatus showed an association with the anatomic outcome of repair (Exp(B) = 0.596; P = .010). Our intraoperative model for the estimation of rotator cuff repair tension showed an inverse correlation of repair tension with healing at the repair site, suggesting that complete healing is less likely with high-tension repairs. A significant association was observed on MRI between a high level of FD of the infraspinatus and repaired tendon integrity. © 2016

40 CFR 63.1005 - Leak repair.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Leak repair. 63.1005 Section 63.1005... Standards for Equipment Leaks-Control Level 1 § 63.1005 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected no later than 15 calendar days after it is detected, except as...

40 CFR 65.105 - Leak repair.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Leak repair. 65.105 Section 65.105... FEDERAL AIR RULE Equipment Leaks § 65.105 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected as soon as practical but not later than 15 calendar days after it is...

Effect of repair resin type and surface treatment on the repair strength of polyamide denture base resin.

Science.gov (United States)

Gundogdu, Mustafa; Yanikoglu, Nuran; Bayindir, Funda; Ciftci, Hilal

2015-01-01

The purpose of the present study was to evaluate the effects of different repair resins and surface treatments on the repair strength of a polyamide denture base material. Polyamide resin specimens were prepared and divided into nine groups according to the surface treatments and repair materials. The flexural strengths were measured with a 3-point bending test. Data were analyzed with a 2-way analysis of variance, and the post-hoc Tukey test (α=0.05). The effects of the surface treatments on the surface of the polyamide resin were examined using scanning electron microscopy. The repair resins and surface treatments significantly affected the repair strength of the polyamide denture base material (p0.05). The flexural strength of the specimens repaired with the polyamide resin was significantly higher than that of those repaired with the heat-polymerized and autopolymerizing acrylic resins.

75 FR 6383 - Lead-Based Paint Renovation, Repair and Painting, and Pre-Renovation Education Activities in...

Science.gov (United States)

2010-02-09

..., Repair and Painting, and Pre- Renovation Education Activities in Target Housing and Child Occupied....C. 2682(c)(3), and a lead-based paint pre-renovation education program in accordance with section... TSCA, and a lead-based paint pre-renovation education program in accordance with section 406(b) of TSCA...

The impact of endovascular repair on specialties performing abdominal aortic aneurysm repair

NARCIS (Netherlands)

Ultee, Klaas H J; Hurks, Rob; Buck, Dominique B.; Dasilva, George S.; Soden, Peter A.; Van Herwaarden, Joost A.; Verhagen, Hence J M; Schermerhorn, Marc L.

2015-01-01

Background Abdominal aortic aneurysm (AAA) repair has been performed by various surgical specialties for many years. Endovascular aneurysm repair (EVAR) may be a disruptive technology, having an impact on which specialties care for patients with AAA. Therefore, we examined the proportion of AAA

The impact of endovascular repair on specialties performing abdominal aortic aneurysm repair

NARCIS (Netherlands)

K.H.J. Ultee (Klaas); R. Hurks (Rob); D.B. Buck (Dominique B.); G.S. Dasilva (George S.); P.A. Soden (Peter A.); J.A. van Herwaarden (Joost); H.J.M. Verhagen (Hence); M.L. Schermerhorn (Marc)

2015-01-01

textabstractBackground Abdominal aortic aneurysm (AAA) repair has been performed by various surgical specialties for many years. Endovascular aneurysm repair (EVAR) may be a disruptive technology, having an impact on which specialties care for patients with AAA. Therefore, we examined the proportion

Treatment and Controversies in Paraesophageal Hernia Repair

Directory of Open Access Journals (Sweden)

P. Marco eFisichella

2015-04-01

Full Text Available Background: Historically all paraesophageal hernias were repaired surgically, today intervention is reserved for symptomatic paraesophageal hernias. In this review, we describe the indications for repair and explore the controversies in paraesophageal hernia repair, which include a comparison of open to laparoscopic paraesophageal hernia repair, the necessity of complete sac excision, the routine performance of fundoplication, and the use of mesh for hernia repair.Methods: We searched Pubmed for papers published between 1980 and 2015 using the following keywords: hiatal hernias, paraesophageal hernias, regurgitation, dysphagia, gastroesophageal reflux disease, aspiration, GERD, endoscopy, manometry, pH monitoring, proton pump inhibitors, anemia, iron deficiency anemia, Nissen fundoplication, sac excision, mesh, mesh repair. Results: Indications for paraesophageal hernia repair have changed, and currently symptomatic paraesophageal hernias are recommended for repair. In addition, it is important not to overlook iron-deficiency anemia and pulmonary complaints, which tend to improve with repair. Current practice favors a laparoscopic approach, complete sac excision, primary crural repair with or without use of mesh, and a routine fundoplication.

Double-Strand DNA Break Repair in Mycobacteria.

Science.gov (United States)

Glickman, Michael S

2014-10-01

Discontinuity of both strands of the chromosome is a lethal event in all living organisms because it compromises chromosome replication. As such, a diversity of DNA repair systems has evolved to repair double-strand DNA breaks (DSBs). In part, this diversity of DSB repair systems has evolved to repair breaks that arise in diverse physiologic circumstances or sequence contexts, including cellular states of nonreplication or breaks that arise between repeats. Mycobacteria elaborate a set of three genetically distinct DNA repair pathways: homologous recombination, nonhomologous end joining, and single-strand annealing. As such, mycobacterial DSB repair diverges substantially from the standard model of prokaryotic DSB repair and represents an attractive new model system. In addition, the presence in mycobacteria of a DSB repair system that can repair DSBs in nonreplicating cells (nonhomologous end joining) or when DSBs arise between repeats (single-strand annealing) has clear potential relevance to Mycobacterium tuberculosis pathogenesis, although the exact role of these systems in M. tuberculosis pathogenesis is still being elucidated. In this article we will review the genetics of mycobacterial DSB repair systems, focusing on recent insights.

Ultrasound determination of rotator cuff tear repairability

Science.gov (United States)

Tse, Andrew K; Lam, Patrick H; Walton, Judie R; Hackett, Lisa

2015-01-01

Background Rotator cuff repair aims to reattach the torn tendon to the greater tuberosity footprint with suture anchors. The present study aimed to assess the diagnostic accuracy of ultrasound in predicting rotator cuff tear repairability and to assess which sonographic and pre-operative features are strongest in predicting repairability. Methods The study was a retrospective analysis of measurements made prospectively in a cohort of 373 patients who had ultrasounds of their shoulder and underwent rotator cuff repair. Measurements of rotator cuff tear size and muscle atrophy were made pre-operatively by ultrasound to enable prediction of rotator cuff repairability. Tears were classified following ultrasound as repairable or irreparable, and were correlated with intra-operative repairability. Results Ultrasound assessment of rotator cuff tear repairability has a sensitivity of 86% (p tear size (p tear size ≥4 cm2 or anteroposterior tear length ≥25 mm indicated an irreparable rotator cuff tear. Conclusions Ultrasound assessment is accurate in predicting rotator cuff tear repairability. Tear size or anteroposterior tear length and age were the best predictors of repairability. PMID:27582996

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

Energy Technology Data Exchange (ETDEWEB)

SUGAMA,T.

2007-01-01

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

Handbook of adhesive bonded structural repair

CERN Document Server

Wegman, Raymond F

1992-01-01

Provides repair methods for adhesive bonded and composite structures; identifies suitable materials and equipment for repairs; describes damage evaluation criteria and techniques, and methods of inspection before and after repair.

Scarf Repair of Composite Laminates

Directory of Open Access Journals (Sweden)

Xie Zonghong

2016-01-01

Full Text Available The use of composite materials, such as carbon-fiber reinforced plastic (CFRP composites, aero-structures has led to an increased need of advanced assembly joining and repair technologies. Adhesive bonded repairs as an alternative to recover full or part of initial strength were investigated. Tests were conducted with the objective of evaluating the effectiveness of techniques used for repairing damage fiber reinforced laminated composites. Failure loads and failure modes were generated and compared with the following parameters: scarf angles, roughness of grind tool and number of external plies. Results showed that scarf angle was the critical parameter and the largest tensile strength was observed with the smallest scarf angle. Besides, the use of external plies at the outer surface could not increase the repairs efficiency for large scarf angle. Preparing the repair surfaces by sanding them with a sander ranging from 60 to 100 grit number had significant effect on the failure load. These results allowed the proposal of design principles for repairing CFRP structures.

Overlapping sphincteroplasty and posterior repair.

Science.gov (United States)

Crane, Andrea K; Myers, Erinn M; Lippmann, Quinn K; Matthews, Catherine A

2014-12-01

Knowledge of how to anatomically reconstruct extensive posterior-compartment defects is variable among gynecologists. The objective of this video is to demonstrate an effective technique of overlapping sphincteroplasty and posterior repair. In this video, a scripted storyboard was constructed that outlines the key surgical steps of a comprehensive posterior compartment repair: (1) surgical incision that permits access to posterior compartment and perineal body, (2) dissection of the rectovaginal space up to the level of the cervix, (3) plication of the rectovaginal muscularis, (4) repair of internal and external anal sphincters, and (5) reconstruction of the perineal body. Using a combination of graphic illustrations and live video footage, tips on repair are highlighted. The goals at the end of repair are to: (1) have improved vaginal caliber, (2) increase rectal tone along the entire posterior vaginal wall, (3) have the posterior vaginal wall at a perpendicular plane to the perineal body, (4) reform the hymenal ring, and (5) not have an overly elongated perineal body. This video provides a step-by-step guide on how to perform an overlapping sphincteroplasty and posterior repair.

Refinement of Foam Backfill Technology for Expedient Airfield Damage Repair; Phase 2: Development of Prototype Foam Dispensing Equipment and Improved Tactics, Techniques and Procedures

Science.gov (United States)

2017-12-01

ER D C TR -1 7- 14 U.S. Air Force Rapid Airfield Damage Repair Modernization Program Refinement of Foam Backfill Technology for...Backfill Technology for Expedient Airfield Damage Repair Phase II: Development of Prototype Foam Dispensing Equipment and Improved Tactics...procedures (TTPs) for rapid airfield damage repair (RADR) using foam backfill technology . Three different prototype foam dispensing systems were

Both base excision repair and nucleotide excision repair in humans are influenced by nutritional factors.

Science.gov (United States)

Brevik, Asgeir; Karlsen, Anette; Azqueta, Amaya; Tirado, Anna Estaban; Blomhoff, Rune; Collins, Andrew

2011-01-01

Lack of reliable assays for DNA repair has largely prevented measurements of DNA repair from being included in human biomonitoring studies. Using newly developed modifications of the comet assay we tested whether a fruit- and antioxidant-rich plant-based intervention could affect base excision repair (BER) and nucleotide excision repair (NER) in a group of 102 male volunteers. BER and NER repair capacities were measured in lymphocytes before and after a dietary intervention lasting 8 weeks. The study had one control group, one group consuming three kiwifruits per day and one group consuming a variety of antioxidant-rich fruits and plant products in addition to their normal diet. DNA strand breaks were reduced following consumption of both kiwifruits (13%, p = 0.05) and antioxidant-rich plant products (20%, p = 0.02). Increased BER (55%, p = 0.01) and reduced NER (-39%, p plant products. Reduced NER was also observed in the kiwifruit group (-38%, p = 0.05), but BER was not affected in this group. Here we have demonstrated that DNA repair is affected by diet and that modified versions of the comet assay can be used to assess activity of different DNA repair pathways in human biomonitoring studies. Copyright © 2010 John Wiley & Sons, Ltd.

Magnetic Resonance Imaging of Cartilage Repair

Science.gov (United States)

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

2011-01-01

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

My journey to DNA repair.

Science.gov (United States)

Lindahl, Tomas

2013-02-01

I completed my medical studies at the Karolinska Institute in Stockholm but have always been devoted to basic research. My longstanding interest is to understand fundamental DNA repair mechanisms in the fields of cancer therapy, inherited human genetic disorders and ancient DNA. I initially measured DNA decay, including rates of base loss and cytosine deamination. I have discovered several important DNA repair proteins and determined their mechanisms of action. The discovery of uracil-DNA glycosylase defined a new category of repair enzymes with each specialized for different types of DNA damage. The base excision repair pathway was first reconstituted with human proteins in my group. Cell-free analysis for mammalian nucleotide excision repair of DNA was also developed in my laboratory. I found multiple distinct DNA ligases in mammalian cells, and led the first genetic and biochemical work on DNA ligases I, III and IV. I discovered the mammalian exonucleases DNase III (TREX1) and IV (FEN1). Interestingly, expression of TREX1 was altered in some human autoimmune diseases. I also showed that the mutagenic DNA adduct O(6)-methylguanine (O(6)mG) is repaired without removing the guanine from DNA, identifying a surprising mechanism by which the methyl group is transferred to a residue in the repair protein itself. A further novel process of DNA repair discovered by my research group is the action of AlkB as an iron-dependent enzyme carrying out oxidative demethylation. Copyright © 2013. Production and hosting by Elsevier Ltd.

The Weekend Effect in AAA Repair.

Science.gov (United States)

O'Donnell, Thomas F X; Li, Chun; Swerdlow, Nicholas J; Liang, Patric; Pothof, Alexander B; Patel, Virendra I; Giles, Kristina A; Malas, Mahmoud B; Schermerhorn, Marc L

2018-04-18

Conflicting reports exist regarding whether patients undergoing surgery on the weekend or later in the week experience worse outcomes. We identified patients undergoing abdominal aortic aneurysm (AAA) repair in the Vascular Quality Initiative between 2009 and 2017 [n = 38,498; 30,537 endovascular aneurysm repair (EVAR) and 7961 open repair]. We utilized mixed effects logistic regression to compare adjusted rates of perioperative mortality based on the day of repair. Tuesday was the most common day for elective repair (22%), Friday for symptomatic repairs (20%), and ruptured aneurysms were evenly distributed. Patients with ruptured aneurysms experienced similar adjusted mortality whether they underwent repair during the week or on weekends. Transfers of ruptured AAA were more common over the weekend. However, patients transferred on the weekend experienced higher adjusted mortality than those transferred during the week (28% vs 21%, P = 0.02), despite the fact that during the week, transferred patients actually experienced lower adjusted mortality than patients treated at the index hospital (21% vs 31%, P AAA repair. However, patients with ruptured AAA transferred on the weekend experienced higher mortality than those transferred during the week, suggesting a need for improvement in weekend transfer processes.

Systems Maintenance Automated Repair Tasks (SMART)

Science.gov (United States)

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

2010-01-01

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

Laparoscopic repair of large suprapubic hernias.

Science.gov (United States)

Sikar, Hasan Ediz; Çetin, Kenan; Eyvaz, Kemal; Kaptanoglu, Levent; Küçük, Hasan Fehmi

2017-09-01

Suprapubic hernia is the term to describe ventral hernias located less than 4 cm above the pubic arch in the midline. Hernias with an upper margin above the arcuate line encounter technical difficulties, and the differences in repair methods forced us to define them as large suprapubic hernias. To present our experience with laparoscopic repair of large suprapubic hernias that allows adequate mesh overlap. Nineteen patients with suprapubic incisional hernias who underwent laparoscopic repair between May 2013 and January 2015 were included in the study. Patients with laparoscopic extraperitoneal repair who had a suprapubic hernia with an upper margin below the arcuate line were excluded. Two men and 17 women, with a mean age of 58.2, underwent laparoscopic repair. Most of the incisions were midline vertical (13/68.4%). Twelve (63.1%) of the patients had previous incisional hernia repair (PIHR group); the mean number of previous incisional hernia repair was 1.4. Mean defect size of the PIHR group was higher than in patients without previous repair - 107.3 cm 2 vs. 50.9 cm 2 (p < 0.05). Mean operating time of the PIHR group was higher than in patients without repair - 126 min vs. 77.9 min (p < 0.05). Although all complications occurred in the PIHR group, there was no statistically significant difference. Laparoscopic repair of large suprapubic hernias can be considered as the first option in treatment. The low recurrence rates reported in the literature and the lack of recurrence, as observed in our study, support this view.

DNA repair in neurons: So if they don't divide what's to repair?

Energy Technology Data Exchange (ETDEWEB)

Fishel, Melissa L. [Department of Pediatrics (Section of Hematology/Oncology), Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, 1044 W. Walnut, Room 302C, Indianapolis, IN 46202 (United States); Vasko, Michael R. [Department of Pharmacology and Toxicology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202 (United States); Kelley, Mark R. [Department of Pediatrics (Section of Hematology/Oncology), Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, 1044 W. Walnut, Room 302C, Indianapolis, IN 46202 (United States) and Department of Pharmacology and Toxicology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202 (United States) and Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 1044 W. Walnut, Room 302C, Indianapolis, IN 46202 (United States)]. E-mail: mkelley@iupui.edu

2007-01-03

Neuronal DNA repair remains one of the most exciting areas for investigation, particularly as a means to compare the DNA repair response in mitotic (cancer) vs. post-mitotic (neuronal) cells. In addition, the role of DNA repair in neuronal cell survival and response to aging and environmental insults is of particular interest. DNA damage caused by reactive oxygen species (ROS) such as generated by mitochondrial respiration includes altered bases, abasic sites, and single- and double-strand breaks which can be prevented by the DNA base excision repair (BER) pathway. Oxidative stress accumulates in the DNA of the human brain over time especially in the mitochondrial DNA (mtDNA) and is proposed to play a critical role in aging and in the pathogenesis of several neurological disorders including Parkinson's disease, ALS, and Alzheimer's diseases. Because DNA damage accumulates in the mtDNA more than nuclear DNA, there is increased interest in DNA repair pathways and the consequence of DNA damage in the mitochondria of neurons. The type of damage that is most likely to occur in neuronal cells is oxidative DNA damage which is primarily removed by the BER pathway. Following the notion that the bulk of neuronal DNA damage is acquired by oxidative DNA damage and ROS, the BER pathway is a likely area of focus for neuronal studies of DNA repair. BER variations in brain aging and pathology in various brain regions and tissues are presented. Therefore, the BER pathway is discussed in greater detail in this review than other repair pathways. Other repair pathways including direct reversal, nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination and non-homologous end joining are also discussed. Finally, there is a growing interest in the role that DNA repair pathways play in the clinical arena as they relate to the neurotoxicity and neuropathy associated with cancer treatments. Among the numerous side effects of cancer treatments, major

Procedures for maintenance and repairs

International Nuclear Information System (INIS)

Pickel, E.

1981-01-01

After a general review of the operation experience in the history of more than 12 operating years, the organization in the plant will be shown with special aspect to quality assurance, capacity of the workshops and connected groups as radiation protection, chemical laboratories etc. The number, time intervals and manpower effort for the repeating tests will be discussed. Reasons and examples for back-fitting activities in the plant are given. Besides special repair and maintenance procedures as repair of the steam generators, in-service inspection of the reactor pressure vessel, repair of a feed-water pipe and repair of the core structure in the pressure vessel, the general system to handle maintenance and repair-work in the KWO-plant will be shown. This includes also the detailed planning of the annual refueling and revision of the plant. (orig./RW)

DNA repair genes

International Nuclear Information System (INIS)

Morimyo, Mitsuoki

1995-01-01

Fission yeast S. pombe is assumed to be a good model for cloning of human DNA repair genes, because human gene is normally expressed in S. pombe and has a very similar protein sequence to yeast protein. We have tried to elucidate the DNA repair mechanisms of S. pombe as a model system for those of mammals. (J.P.N.)

In service inspection and repair of sodium cooled ASTRID prototype

Energy Technology Data Exchange (ETDEWEB)

Baque, F.; Jadot, F. [French Atomic Commission, Cadarache Centre, 13108 Saint Paul lez Durance Cedex, (France); Marlier, R. [AREVA, 10 rue Recamier, 69456 Lyon cedex 06, (France); Saillant, J-F. [AREVA/NDE Solutions, 4 rue Thomas Dumorey, BP 70385, 71109 Chalon sur Saone Cedex, (France); Delalande, V. [EDF R and D, 6, quai Watier, 78400 Chatou, (France)

2015-07-01

In the frame of the large R and D work which is performed for the future ASTRID sodium cooled prototype, In Service Inspection and Repair (ISI and R) has been identified as a major issue to be taken into account in order to enlarge the plant safety, to consolidate its availability and to protect the associated investment. After the first part of pre-conceptual design phase (2008-2012), the running second part of pre-conceptual phase (2013-2015) allows to increase the ISI and R tool ability for immersed sodium structures of ASTRID, at about 200 deg. C, on the basis of consolidated specifications and thanks to their qualification through more and more realistic laboratory tests and simulation with CIVA code. ISI and R items are being developed and qualified during a pluri-annual program which mainly deals with the reactor block structures, the primary components and circuit, and the Power Conversion System. It ensures a strong connection between the reactor designers and inspection specialists, as the optimization of inspectability and repairability is looked at: this already induced specific rules for design, in order to shorten and ease the ISI and R operations, which have been merged into RCC-MRx rules. In the frame of increasing technology readiness level with corresponding performance demonstration, this paper presents R and D dealing with the ISI and R items: it highlights the sensor development (both ultrasonic and electromagnetic concepts, compatible with sodium at 200 deg. C), then their applications for ASTRID structure control (under sodium telemetry, imaging and NDE). Activity for repair is also presented (a single laser tool for sodium sweeping, machining and welding), and finally the effort for associated robotic (generic program for ASTRID applications, specific technological tools for sodium medium, tight immersed bell). The main results of testing and simulation are given for telemetry, vision, NDE applications, laser process repair and under sodium

Radiation shielding design for a hot repair facility

International Nuclear Information System (INIS)

Courtney, J.C.; Dwight, C.C.

1991-01-01

A new repair and decontamination area is being built to support operations at the demonstration fuel cycle facility for the Integral Fast Reactor program at Argonne National Laboratory's site at the Idaho National Engineering Laboratory. Provisions are made for remote, glove wall, and contact maintenance on equipment removed from hot cells where spent fuel will be electrochemically processed and recycled to the Experimental Breeder Reactor-II. The source for the shielding design is contamination from a mix of fission and activation products present on items removed from the hot cells. The repair facility also serves as a transfer path for radioactive waste produced by processing operations. Radiation shields are designed to limit dose rates to no more than 5 microSv h-1 (0.5 mrem h-1) in normally occupied areas. Point kernel calculations with buildup factors have been used to design the shielding and to position radiation monitors within the area

ASTRID In Service Inspection and Repair: Review of R&D program and associated results

International Nuclear Information System (INIS)

Baqué, François; Jadot, Françoise; Bourdais, Florian le; Sibilo, Julien; Augem, Jean-Michel; Gastaldi, Olivier

2013-01-01

In Service Inspection & Repair (ISI&R): → range of provisions enabling to verify that the equipments state is in compliance with design criteria; → other range of provisions allowing to characterize an abnormal situation (failure, operation mistake) and to perform necessary actions to reach again an achievable plant configuration

Learning curve analysis of mitral valve repair using telemanipulative technology.

Science.gov (United States)

Charland, Patrick J; Robbins, Tom; Rodriguez, Evilio; Nifong, Wiley L; Chitwood, Randolph W

2011-08-01

To determine if the time required to perform mitral valve repairs using telemanipulation technology decreases with experience and how that decrease is influenced by patient and procedure variables. A single-center retrospective review was conducted using perioperative and outcomes data collected contemporaneously on 458 mitral valve repair surgeries using telemanipulative technology. A regression model was constructed to assess learning with this technology and predict total robot time using multiple predictive variables. Statistical analysis was used to determine if models were significantly useful, to rule out correlation between predictor variables, and to identify terms that did not contribute to the prediction of total robot time. We found a statistically significant learning curve (P learning percentage∗ derived from total robot times† for the first 458 recorded cases of mitral valve repair using telemanipulative technology is 95% (R(2) = .40). More than one third of the variability in total robot time can be explained through our model using the following variables: type of repair (chordal procedures, ablations, and leaflet resections), band size, use of clips alone in band implantation, and the presence of a fellow at bedside (P Learning in mitral valve repair surgery using telemanipulative technology occurs at the East Carolina Heart Institute according to a logarithmic curve, with a learning percentage of 95%. From our regression output, we can make an approximate prediction of total robot time using an additive model. These metrics can be used by programs for benchmarking to manage the implementation of this new technology, as well as for capacity planning, scheduling, and capital budget analysis. Copyright © 2011 The American Association for Thoracic Surgery. All rights reserved.

Repair of steam turbines by welding

International Nuclear Information System (INIS)

Bohnstedt, H.J.; Loebert, P.

1987-01-01

In some cases, turbine parts can be repaired by welding, even rotating parts such as the shaft or the blades. Practical examples of successful repair work are explained, as for instance: welding of the last web of the turbine wheel of two MD-rotors, repair of erosion damage on turbine blades, of solid-matter erosion on a medium-pressure blading, or welding repair of a high-pressure turbine casing. (DG) [de

IRIG 106 Chapter 10 Programmers Handbook

Science.gov (United States)

2016-08-16

szDataItem. Specific parsers are called for specific attribute types, indicated by the first letter of the code name. After all TMATS attributes are...EnI106Status I106_CALL_DECL enI106Ch10Close(int iHandle) { // If handles have been init’ed then bail if

Current Biomechanical Concepts for Rotator Cuff Repair

Science.gov (United States)

2013-01-01

For the past few decades, the repair of rotator cuff tears has evolved significantly with advances in arthroscopy techniques, suture anchors and instrumentation. From the biomechanical perspective, the focus in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. To accomplish these objectives, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. In addition, the healing response may be compromised by intrinsic factors such as decreased vascularity, hypoxia, and fibrocartilaginous changes or aforementioned extrinsic compression factors. Furthermore, it is well documented that torn rotator cuff muscles have a tendency to atrophy and become subject to fatty infiltration which may affect the longevity of the repair. Despite all the aforementioned factors, initial fixation strength is an essential consideration in optimizing rotator cuff repair. Therefore, numerous biomechanical studies have focused on elucidating the strongest devices, knots, and repair configurations to improve contact characteristics for rotator cuff repair. In this review, the biomechanical concepts behind current rotator cuff repair techniques will be reviewed and discussed. PMID:23730471

Early discharge after external anal sphincter repair

DEFF Research Database (Denmark)

Rosenberg, J; Kehlet, H

1999-01-01

and complications within 30 days after the operation. Surgery was performed during the period of March 1993 to May 1997. The accelerated-stay program included preoperative information, no premedication, a surgical procedure without colostomy, single-dose prophylactic antibiotics, paracetamol for analgesia, free...... surgery and 5 patients stayed for 48 hours after the operation. There was no 30-day morbidity, and no patient received a colostomy in conjunction with the sphincter repair. Fourteen of 19 patients available for follow-up reported a significantly improved functional result compared with preoperative state...

Human DNA repair and recombination genes

International Nuclear Information System (INIS)

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

1988-09-01

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

A study of everyday repair: informing interaction design

OpenAIRE

Maestri, Leah Adriana

2012-01-01

Repair is typically seen in design as the restoration of broken objects to their original state. Repair by non-experts, or everyday repair, can often lead to novel forms of repair resulting in the creative repurposing of objects that are often unforeseen by designers. Using a grounded theory approach, this study describes key aspects of repair including: the techniques non-experts employ for repairing their objects; the motivations that prompt acts of repair; and the outcomes that result fr...

Molecular biological mechanisms I. DNA repair

International Nuclear Information System (INIS)

Friedl, A.A.

2000-01-01

Cells of all living systems possess a variety of mechanisms that allow to repair spontaneous and exogeneously induced DNA damage. DNA repair deficiencies may invoke enhanced sensitivity towards DNA-damaging agents such as ionizing radiation. They may also enhance the risk of cancer development, both spontaneously or after induction. This article reviews several DNA repair mechanisms, especially those dealing with DNA double-strand breaks, and describes hereditary diseases associated with DNA repair defects. (orig.) [de

Primary tetralogy of Fallot repair: predictors of intensive care unit morbidity.

Science.gov (United States)

Egbe, Alexander C; Uppu, Santosh C; Mittnacht, Alexander J C; Joashi, Umesh; Ho, Deborah; Nguyen, Khanh; Srivastava, Shubhika

2014-09-01

Primary repair of tetralogy of Fallot has low surgical mortality, but some patients still experience significant postoperative morbidity. Our objectives were to review our institutional experience with primary tetralogy of Fallot repair, and identify predictors of intensive care unit morbidity. We reviewed all patients with tetralogy of Fallot who underwent primary repair in infancy from 2001 to 2012. Preoperative, operative, and postoperative demographic and morphologic data were analyzed. Intensive care unit morbidity was defined as prolonged intensive care unit stay (≥ 7 days) and/or prolonged duration of mechanical ventilation (≥ 48 h). 97 patients who underwent primary surgical repair during the study period were included in the study. The median age was 4.9 months (range 1-9 months) and the median weight was 5.3 kg (range 3.1-9.8 kg). There was no early surgical mortality. The incidence of junctional ectopic tachycardia and persistent complete heart block was 2% and 1%, respectively. The median intensive care unit stay was 6 days (range 2-21 days) and the median duration of mechanical ventilation was 19 h (range 0-136 h). Age and weight were independent predictors of intensive care unit stay, while surgical era predicted the duration of mechanical ventilation. Primary tetralogy of Fallot repair is a safe procedure with low mortality and morbidity in a medium-sized program with outcomes comparable to national standards. Age and weight at the time of surgery were significant predictors of morbidity. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Draft environmental statement related to steam generator repair at H.B. Robinson Steam Electric Plant Unit No. 2, (Docket No. 50-261)

International Nuclear Information System (INIS)

1983-09-01

The staff has considered the environmental impacts and economic costs of the proposed steam generator repair at the H.B. Robinson Steam Electric Plant Unit No. 2 along with reasonable alternatives to the proposed action. The staff has concluded that the proposed repair will not significantly affect the quality of the human environment and that there are no preferable alternatives to the proposed action. Furthermore, any impacts from the repair program are outweighted by its benefits

Metabolic modulation of mammalian DNA excision repair

Energy Technology Data Exchange (ETDEWEB)

Schrader, T.J.

1988-01-01

First, ultraviolet light (UVL)- and dimethylsulfate (DMS)-induced excision repair was examined in quiescent and lectin-stimulated bovine lymphocytes. Upon mitogenic stimulation, UVL-induced repair increased by a factor of 2 to 3, and reached this maximum 2 days before the onset of DNA replication. However, DMS-induced repair increased sevenfold in parallel with DNA replication. Repair patch sizes were smaller for DMS-induced damage reflecting patches of 7 nucleotides in quiescent lymphocytes compared to 20 nucleotides induced by UVL. The patch size increased during lymphocyte stimulation until one day prior to the peak of DNA replication when patch sizes of 45 and 35 nucleotides were produced in response to UVL- and DMS-induced damage, respectively. At the peak of DNA replication, the patch sizes were equal for both damaging agents at 34 nucleotides. In the second study, a small amount of repair replication was observed in undamaged quiescent and concanavalin A-stimulated bovine lymphocytes as well as in human T98G glioblastoma cells. Repair incorporation doubled in the presence of hydroxyurea. Thirdly, the enhanced repair replication induced by the poly (ADP-ribose) polymerase inhibitor, 3-aminobenzamide, (3-AB), could not be correlated either with an increased rate of repair in the presence of 3-AB or with the use of hydroxyurea in the repair protocol. Finally, treatment of unstimulated lymphocytes with hyperthermia was accompanied by decreased repair replication while the repair patches remained constant at 20 nucleotides.

Flexural Strength of Carbon Fiber Reinforced Polymer Repaired Cracked Rectangular Hollow Section Steel Beams

Directory of Open Access Journals (Sweden)

Tao Chen

2015-01-01

Full Text Available The flexural behavior of rectangular hollow section (RHS steel beams with initial crack strengthened externally with carbon fiber reinforced polymer (CFRP plates was studied. Eight specimens were tested under three-point loading to failure. The experimental program included three beams as control specimens and five beams strengthened with CFRP plates with or without prestressing. The load deflection curves were graphed and failure patterns were observed. The yield loads and ultimate loads with or without repairing were compared together with the strain distributions of the CFRP plate. It was concluded that yield loads of cracked beams could be enhanced with repairing. Meanwhile, the ultimate loads were increased to some extent. The effect of repair became significant with the increase of the initial crack depth. The failure patterns of the repaired specimens were similar to those of the control ones. Mechanical clamping at the CFRP plate ends was necessary to avoid premature peeling between the CFRP plate and the steel beam. The stress levels in CFRP plates were relatively low during the tests. The use of prestressing could improve the utilization efficiency of CFRP plates. It could be concluded that the patching repair could be used to restore the load bearing capacity of the deficient steel beams.

Self-repair of cracks in brittle material systems

Science.gov (United States)

Dry, Carolyn M.

2016-04-01

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

Impact of radiotherapy on PBMCs DNA repair capacity - Use of a multiplexed functional repair assay

International Nuclear Information System (INIS)

Sauvaigo, S.; Sarrazy, F.; Breton, J.; Caillat, S.; Chapuis, V.

2012-01-01

Radiation therapy is an essential part of cancer treatment as about 50% of patients will receive radiations at least once. Significant broad variation in radiosensitivity has been demonstrated in patients. About 5-10% of patients develop acute toxicity after radiotherapy. Therefore there is a need for the identification of markers able to predict the occurrence of adverse effects and thus adapt the radiotherapy regimen for radiosensitive patients. As a first step toward this goal, and considering the DNA repair defects associated with hypersensitivity radiation syndromes, we investigated the DNA repair phenotype of patients receiving radiotherapy. More precisely, we used a functional repair assay on support to follow the evolution of the glycosylases/AP endonuclease activities of PBMCs extracts of a series of patients during the time course of radiotherapy. For each patient, we collected one PBMCs sample before the first radiotherapy application (S1) and three samples after (S2 to S4) (one day and one week after application 1, and one at the end of the radiotherapy protocol). These four samples have been analysed for 11 donors. Clustering analyses of the results demonstrated a great heterogeneity of responses among the patients. Interestingly, this heterogeneity decreased between S1 and S4 where only 2 classes of patients remained if we except one patient that exhibited an atypical DNA repair phenotype. Furthermore, we showed that repair of several oxidized bases significantly increased between S1 and S3 or S4 (8oxoG, thymine glycol, A paired with 8oxoG), suggesting an adaptation of patients repair systems to the oxidative stress generated by the ionising radiations. Our preliminary results provided evidence that the DNA repair phenotype was impacted by the radiotherapy regimen. Further characterization of patients with known repair defects are needed to determine if atypical repair phenotypes could be associated with radiotherapy complications. Finally

Country program review Myanmar

International Nuclear Information System (INIS)

Boussaha, A.; Naqvi, S.H.M.; Poshyachinda, M.; Con, T.T.; Nemoto, S.

1994-03-01

Review of the past and present IAEA technical cooperation activities in the field of repair and maintenance of nuclear instrumentation and sectoral programs and institutional review in the same field are presented

Country program review Myanmar

Energy Technology Data Exchange (ETDEWEB)

Boussaha, A; Naqvi, S H.M.; Poshyachinda, M; Con, T T; Nemoto, S

1994-03-01

Review of the past and present IAEA technical cooperation activities in the field of repair and maintenance of nuclear instrumentation and sectoral programs and institutional review in the same field are presented.

DNA Damage, Repair, and Cancer Metabolism

Science.gov (United States)

Turgeon, Marc-Olivier; Perry, Nicholas J. S.; Poulogiannis, George

2018-01-01

Although there has been a renewed interest in the field of cancer metabolism in the last decade, the link between metabolism and DNA damage/DNA repair in cancer has yet to be appreciably explored. In this review, we examine the evidence connecting DNA damage and repair mechanisms with cell metabolism through three principal links. (1) Regulation of methyl- and acetyl-group donors through different metabolic pathways can impact DNA folding and remodeling, an essential part of accurate double strand break repair. (2) Glutamine, aspartate, and other nutrients are essential for de novo nucleotide synthesis, which dictates the availability of the nucleotide pool, and thereby influences DNA repair and replication. (3) Reactive oxygen species, which can increase oxidative DNA damage and hence the load of the DNA-repair machinery, are regulated through different metabolic pathways. Interestingly, while metabolism affects DNA repair, DNA damage can also induce metabolic rewiring. Activation of the DNA damage response (DDR) triggers an increase in nucleotide synthesis and anabolic glucose metabolism, while also reducing glutamine anaplerosis. Furthermore, mutations in genes involved in the DDR and DNA repair also lead to metabolic rewiring. Links between cancer metabolism and DNA damage/DNA repair are increasingly apparent, yielding opportunities to investigate the mechanistic basis behind potential metabolic vulnerabilities of a substantial fraction of tumors. PMID:29459886

DNA repair in PHA stimulated human lymphocytes

International Nuclear Information System (INIS)

Catena, C.; Mattoni, A.

1984-01-01

Damage an repair of radiation induced DNA strand breaks were measured by alkaline lysis and hydroxyapatite chromatography. PHA stimulated human lymphocytes show that the rejoining process is complete within the first 50 min., afterwords secondary DNA damage and chromatid aberration. DNA repair, in synchronized culture, allows to evaluate individual repair capacity and this in turn can contribute to the discovery of individual who, although they do not demonstrate apparent clinical signs, are carriers of DNA repair deficiency. Being evident that a correlation exists between DNA repair capacity and carcinogenesis, the possibility of evaluating the existent relationship between DNA repair and survival in tumor cells comes therefore into discussion

Small-Molecule Inhibitors Targeting DNA Repair and DNA Repair Deficiency in Research and Cancer Therapy.

Science.gov (United States)

Hengel, Sarah R; Spies, M Ashley; Spies, Maria

2017-09-21

To maintain stable genomes and to avoid cancer and aging, cells need to repair a multitude of deleterious DNA lesions, which arise constantly in every cell. Processes that support genome integrity in normal cells, however, allow cancer cells to develop resistance to radiation and DNA-damaging chemotherapeutics. Chemical inhibition of the key DNA repair proteins and pharmacologically induced synthetic lethality have become instrumental in both dissecting the complex DNA repair networks and as promising anticancer agents. The difficulty in capitalizing on synthetically lethal interactions in cancer cells is that many potential targets do not possess well-defined small-molecule binding determinates. In this review, we discuss several successful campaigns to identify and leverage small-molecule inhibitors of the DNA repair proteins, from PARP1, a paradigm case for clinically successful small-molecule inhibitors, to coveted new targets, such as RAD51 recombinase, RAD52 DNA repair protein, MRE11 nuclease, and WRN DNA helicase. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Friedberg, Errol C

2016-01-01

This article reviews the early history of the discovery of an DNA repair pathway designated as base excision repair (BER), since in contrast to the enzyme-catalyzed removal of damaged bases from DNA as nucleotides [called nucleotide excision repair (NER)], BER involves the removal of damaged or inappropriate bases, such as the presence of uracil instead of thymine, from DNA as free bases. Copyright © 2015. Published by Elsevier B.V.

Revision Arthroscopic Repair Versus Latarjet Procedure in Patients With Recurrent Instability After Initial Repair Attempt: A Cost-Effectiveness Model.

Science.gov (United States)

Makhni, Eric C; Lamba, Nayan; Swart, Eric; Steinhaus, Michael E; Ahmad, Christopher S; Romeo, Anthony A; Verma, Nikhil N

2016-09-01

To compare the cost-effectiveness of arthroscopic revision instability repair and Latarjet procedure in treating patients with recurrent instability after initial arthroscopic instability repair. An expected-value decision analysis of revision arthroscopic instability repair compared with Latarjet procedure for recurrent instability followed by failed repair attempt was modeled. Inputs regarding procedure cost, clinical outcomes, and health utilities were derived from the literature. Compared with revision arthroscopic repair, Latarjet was less expensive ($13,672 v $15,287) with improved clinical outcomes (43.78 v 36.76 quality-adjusted life-years). Both arthroscopic repair and Latarjet were cost-effective compared with nonoperative treatment (incremental cost-effectiveness ratios of 3,082 and 1,141, respectively). Results from sensitivity analyses indicate that under scenarios of high rates of stability postoperatively, along with improved clinical outcome scores, revision arthroscopic repair becomes increasingly cost-effective. Latarjet procedure for failed instability repair is a cost-effective treatment option, with lower costs and improved clinical outcomes compared with revision arthroscopic instability repair. However, surgeons must still incorporate clinical judgment into treatment algorithm formation. Level IV, expected value decision analysis. Copyright © 2016. Published by Elsevier Inc.

Two-Tunnel Transtibial Repair of Radial Meniscus Tears Produces Comparable Results to Inside-Out Repair of Vertical Meniscus Tears.

Science.gov (United States)

Cinque, Mark E; Geeslin, Andrew G; Chahla, Jorge; Dornan, Grant J; LaPrade, Robert F

2017-08-01

Radial meniscus tears disrupt the circumferential fibers and thereby compromise meniscus integrity. Historically, radial tears were often treated with meniscectomy because of an incomplete understanding of the biomechanical consequences of these tears, limited information regarding the biomechanical performance of repair, and the technical difficulty associated with repair. There is a paucity of studies on the outcomes of the repair of radial meniscus tears. Purpose/Hypothesis: The purpose was to determine the outcomes of 2-tunnel transtibial repair of radial meniscus tears and compare these results to the outcomes of patients who underwent the repair of vertical meniscus tears with a minimum of 2-year follow-up. The hypothesis was that radial and vertical meniscus tear repair outcomes were comparable. Cohort study; Level of evidence, 3. Patients who underwent 2-tunnel transtibial pullout repair for a radial meniscus tear were included in this study and compared with patients who underwent inside-out repair for a vertical meniscus tear. Subjective questionnaires were administered preoperatively and at a minimum of 2-year follow-up, including the Lysholm score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Short Form-12 (SF-12) physical component summary (PCS), the Tegner activity scale, and patient satisfaction. Analysis of covariance was used to compare postoperative outcome scores between the meniscus repair groups while accounting for baseline scores. Adjusted mean effects relative to the radial repair group were reported with 95% CIs. Twenty-seven patients who underwent 2-tunnel transtibial pullout repair for radial meniscus tears and 33 patients who underwent inside-out repair for vertical meniscus tears were available for follow-up at a mean of 3.5 years (range, 2.0-5.4 years). No preoperative outcome score significantly differed between the groups. There were no significant group differences for any of the 2-year

Meniscal repair by fibrocartilage in the dog : Characterization of the repair tissue and the role of vascularity

NARCIS (Netherlands)

Veth, RPH; Jansen, HWB; Nielsen, HKL; deGroot, JH; Pennings, AJ; Kuijer, R

Lesions in the avascular part of 20 canine menisci were repaired by implantation of a porous polyurethane. Seven menisci were not repaired and served as controls. The repair tissue was characterized by biochemical and immunological analysis. The role of vascularity in healing was studied by

30 CFR 56.6801 - Vehicle repair.

Science.gov (United States)

2010-07-01

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

Shuttle Repair Tools Automate Vehicle Maintenance

Science.gov (United States)

2013-01-01

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

Repairing fuel for reinsertion

International Nuclear Information System (INIS)

Krukshenk, A.

1986-01-01

Eqiupment for nuclear reactor fuel assembly repairing produced by Westinghouse and Brawn Bovery companies is described. Repair of failed fuel assemblies replacement of defect fuel elements gives a noticeable economical effect. Thus if the cost of a new fuel assembly is 450-500 thousand dollars, the replacement of one fuel element in it costs approximately 40-60 thousand dollars. In simple cases repairing includes either removal of failed fuel elements from a fuel assembly and its reinsertion with the rest of fuel elements into the reactor core (reactor refueling), or replacement of unfailed fuel elements from one fuel assembly to a new one (fuel assembly overhaul and reconditioning)

Bacteriophage T4 gene 32 participates in excision repair as well as recombinational repair of UV damages

International Nuclear Information System (INIS)

Mosig, G.

1985-01-01

Gene 32 of phage T4 has been shown previously to be involved in recombinational repair of UV damages but, based on a mutant study, was thought not to be required for excision repair. However, a comparison of UV-inactivation curves of several gene 32 mutants grown under conditions permissive for progeny production in wild-type or polA- hosts demonstrates that gene 32 participates in both kinds of repair. Different gene 32 mutations differentially inactivate these repair functions. Under conditions permissive for DNA replication and progeny production, all gene 32 mutants investigated here are partially defective in recombinational repair, whereas only two of them, P7 and P401, are also defective in excision repair. P401 is the only mutant whose final slope of the inactivation curve is significantly steeper than that of wild-type T4. These results are discussed in terms of interactions of gp32, a single-stranded DNA-binding protein, with DNA and with other proteins

Snowmobile Repair. Teacher Edition.

Science.gov (United States)

Hennessy, Stephen S.; Conrad, Rex

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

Innovative repair of subsidence damage

International Nuclear Information System (INIS)

Marino, G.G.

1992-01-01

In order to improve handling of subsidence damages the Illinois Mine Subsidence Insurance Fund supported the development of novel cost-effective methods of repair. The research in developing the repairs was directed towards the most common and costly damages that had been observed. As a result repair techniques were designed for structurally cracked foundations in the tension zone; structurally cracked foundations in the compression zone; and damaged or undamaged tilted foundations. When appropriate the postulated methods would result in: 1. significant cost savings (over conventional procedures); 2. a structural capacity greater than when the foundation was uncracked; and 3. an aesthetic appeal. All the postulated repair methodologies were laboratory and/or field tested. This paper will summarize the essentials of each technique developed and the test results

Laparoscopic inguinal hernia repair: gold standard in bilateral hernia repair? Results of more than 2800 patients in comparison to literature.

Science.gov (United States)

Wauschkuhn, Constantin Aurel; Schwarz, Jochen; Boekeler, Ulf; Bittner, Reinhard

2010-12-01

Advantages and disadvantages of open and endoscopic hernia surgery are still being discussed. Until now there has been no study that evaluated the advantages and disadvantages of bilateral hernia repair in a large number of patients. Our prospectively collected database was analyzed to compare the results of laparoscopic bilateral with laparoscopic unilateral hernia repair. We then compared these results with the results of a literature review regarding open and laparoscopic bilateral hernia repair. From April 1993 to December 2007 there were 7240 patients with unilateral primary hernia (PH) and 2880 patients with bilateral hernia (5760 hernias) who underwent laparoscopic transabdominal preperitoneal patch plastic (TAPP). Of the 10,120 patients, 28.5% had bilateral hernias. Adjusted for the number of patients operated on, the mean duration of surgery for unilateral hernia repair was shorter than that for bilateral repair (45 vs. 70 min), but period of disability (14 vs. 14 days) was the same. Adjusted for the number of hernias repaired, morbidity (1.9 vs. 1.4%), reoperation (0.5 vs. 0.43%), and recurrence rate (0.63 vs. 0.42%) were similar for unilateral versus bilateral repair, respectively. The review of the literature shows a significantly shorter time out of work after laparoscopic bilateral repair than after the bilateral open approach. Simultaneous laparoscopic repair of bilateral inguinal hernias does not increase the risk for the patient and has an equal length of down time compared with unilateral repair. According to literature, recovery after laparoscopic repair is faster than after open simultaneous repair. Laparoscopic/endoscopic inguinal hernia repair of bilateral hernias should be recommended as the gold standard.

The two faces of plan repair

NARCIS (Netherlands)

Van der Krogt, R.P.J.; De Weerdt, M.M.

2004-01-01

Plan repair has two faces. Alternately, a plan repair method looks like a planning method, or looks like a method that does exactly the opposite, i.e., removing actions from a plan. We propose a general framework for plan repair that shows the relation between these two alternating steps. Any plan

Concrete structures protection, repair and rehabilitation

CERN Document Server

Woodson, R Dodge

2009-01-01

The success of a repair or rehabilitation project depends on the specific plans designed for it. Concrete Structures: Protection, Repair and Rehabilitation provides guidance on evaluating the condition of the concrete in a structure, relating the condition of the concrete to the underlying cause or causes of that condition, selecting an appropriate repair material and method for any deficiency found, and using the selected materials and methods to repair or rehabilitate the structure. Guidance is also provided for engineers focused on maintaining concrete and preparing concrete investigation r

DNA damage and repair in plants

International Nuclear Information System (INIS)

Britt, A.B.

1996-01-01

The biological impact of any DNA damaging agent is a combined function of the chemical nature of the induced lesions and the efficiency and accuracy of their repair. Although much has been learned frommicrobes and mammals about both the repair of DNA damage and the biological effects of the persistence of these lesions, much remains to be learned about the mechanism and tissue-specificity of repair in plants. This review focuses on recent work on the induction and repair of DNA damage in higher plants, with special emphasis on UV-induced DNA damage products. (author)

Imaging of cartilage repair procedures

International Nuclear Information System (INIS)

Sanghvi, Darshana; Munshi, Mihir; Pardiwala, Dinshaw

2014-01-01

The rationale for cartilage repair is to prevent precocious osteoarthritis in untreated focal cartilage injuries in the young and middle-aged population. The gamut of surgical techniques, normal postoperative radiological appearances, and possible complications have been described. An objective method of recording the quality of repair tissue is with the magnetic resonance observation of cartilage repair tissue (MOCART) score. This scoring system evaluates nine parameters that include the extent of defect filling, border zone integration, signal intensity, quality of structure and surface, subchondral bone, subchondral lamina, and records presence or absence of synovitis and adhesions. The five common techniques of cartilage repair currently offered include bone marrow stimulation (microfracture or drilling), mosaicplasty, synthetic resorbable scaffold grafts, osteochondral allograft transplants, and autologous chondrocyte implantation (ACI). Complications of cartilage repair procedures that may be demonstrated on magnetic resonance imaging (MRI) include plug loosening, graft protuberance, graft depression, and collapse in mosaicplasty, graft hypertrophy in ACI, and immune response leading to graft rejection, which is more common with synthetic grafts and cadaveric allografts

Human mismatch repair protein hMutLα is required to repair short slipped-DNAs of trinucleotide repeats.

Science.gov (United States)

Panigrahi, Gagan B; Slean, Meghan M; Simard, Jodie P; Pearson, Christopher E

2012-12-07

Mismatch repair (MMR) is required for proper maintenance of the genome by protecting against mutations. The mismatch repair system has also been implicated as a driver of certain mutations, including disease-associated trinucleotide repeat instability. We recently revealed a requirement of hMutSβ in the repair of short slip-outs containing a single CTG repeat unit (1). The involvement of other MMR proteins in short trinucleotide repeat slip-out repair is unknown. Here we show that hMutLα is required for the highly efficient in vitro repair of single CTG repeat slip-outs, to the same degree as hMutSβ. HEK293T cell extracts, deficient in hMLH1, are unable to process single-repeat slip-outs, but are functional when complemented with hMutLα. The MMR-deficient hMLH1 mutant, T117M, which has a point mutation proximal to the ATP-binding domain, is defective in slip-out repair, further supporting a requirement for hMLH1 in the processing of short slip-outs and possibly the involvement of hMHL1 ATPase activity. Extracts of hPMS2-deficient HEC-1-A cells, which express hMLH1, hMLH3, and hPMS1, are only functional when complemented with hMutLα, indicating that neither hMutLβ nor hMutLγ is sufficient to repair short slip-outs. The resolution of clustered short slip-outs, which are poorly repaired, was partially dependent upon a functional hMutLα. The joint involvement of hMutSβ and hMutLα suggests that repeat instability may be the result of aberrant outcomes of repair attempts.

About the Collision Repair Campaign

Science.gov (United States)

EPA developed the Collision Repair Campaign to focus on meaningful risk reduction in the Collision Repair source sector to complement ongoing community air toxics work and attain reductions at a faster rate.

Composite Repair System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — GTL has developed an innovative composite repair methodology known as the Composite Repair System (CRS). In this phase I effort, CRS is being developed for the...

Vesicovaginal Fistula Repair During Pregnancy

African Journals Online (AJOL)

Vesicovaginal Fistula Repair During Pregnancy: A Case Report ... Abstract. We report a repair of Vesicovaginal fistula during pregnancy that was aimed at preventing another spontaneous ... practices that encourage teenage marriage and girl.

Heterogenous mismatch-repair status in colorectal cancer

DEFF Research Database (Denmark)

Joost, Patrick; Veurink, Nynke; Holck, Susanne

2014-01-01

BACKGROUND: Immunohistochemical staining for mismatch repair proteins is efficient and widely used to identify mismatch repair defective tumors. The tumors typically show uniform and widespread loss of MMR protein staining. We identified and characterized colorectal cancers with alternative......, heterogenous mismatch repair protein staining in order to delineate expression patterns and underlying mechanisms. METHODS: Heterogenous staining patterns that affected at least one of the mismatch repair proteins MLH1, PMS2, MSH2 and MSH6 were identified in 14 colorectal cancers. Based on alternative....... CONCLUSIONS: Heterogenous mismatch repair status can be demonstrated in colorectal cancer. Though rare, attention to this phenomenon is recommended since it corresponds to differences in mismatch repair status that are relevant for correct classification. VIRTUAL SLIDES: The virtual slide(s) for this article...

A cell-free scaffold-based cartilage repair provides improved function hyaline-like repair at one year.

Science.gov (United States)

Siclari, Alberto; Mascaro, Gennaro; Gentili, Chiara; Cancedda, Ranieri; Boux, Eugenio

2012-03-01

Bone marrow stimulation techniques in cartilage repair such as drilling are limited by the formation of fibrous to hyaline-like repair tissue. It has been suggested such techniques can be enhanced by covering the defect with scaffolds. We present an innovative approach using a polyglycolic acid (PGA)-hyaluronan scaffold with platelet-rich-plasma (PRP) in drilling. We asked whether (1) PRP immersed in a cell-free PGA-hyaluronan scaffold improves patient-reported 1-year outcomes for the Knee injury and Osteoarthritis Score (KOOS), and (2) implantation of the scaffold in combination with bone marrow stimulation leads to the formation of hyaline-like cartilage repair tissue. We reviewed 52 patients who had arthroscopic implantation of the PGA-hyaluronan scaffold immersed with PRP in articular cartilage defects of the knee pretreated with Pridie drilling. Patients were assessed by KOOS. At 9 months followup, histologic staining was performed in specimens obtained from five patients to assess the repair tissue quality. The KOOS subscores improved for pain (55 to 91), symptoms (57 to 88), activities of daily living (69 to 86), sports and recreation (36 to 70), and quality of life (38 to 73). The histologic evaluation showed a homogeneous hyaline-like cartilage repair tissue. The cell-free PGA-hyaluronan scaffold combined with PRP leads to cartilage repair and improved patient-reported outcomes (KOOS) during 12 months of followup. Histologic sections showed morphologic features of hyaline-like repair tissue. Long-term followup is needed to determine if the cartilage repair tissue is durable. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Radiation damage and its repair in non-sporulating bacteria

International Nuclear Information System (INIS)

Moseley, B.E.B.

1984-01-01

A review is given of radiation damage and its repair in non-sporulating bacteria. The identification and measurement of radiation damage in the DNA of the bacteria after exposure to ultraviolet radiation and ionizing radiation is described. Measuring the extent of DNA repair and ways of isolating repair mutants are also described. The DNA repair mechanisms for UV-induced damage are discussed including photoreactivation repair, excision repair, post-replication recombination repair and induced error-prone repair. The DNA repair mechanisms for ionizing radiation damage are also discussed including the repair of both single and double-strand breaks. Other aspects discussed include the effects of growth, irradiation medium and recovery medium on survival, DNA repair in humans, the commercial use of UV and ionizing radiations and the future of ionizing irradiation as a food treatment process. (U.K.)

Stochastic Modelling Of The Repairable System

Directory of Open Access Journals (Sweden)

Andrzejczak Karol

2015-11-01

Full Text Available All reliability models consisting of random time factors form stochastic processes. In this paper we recall the definitions of the most common point processes which are used for modelling of repairable systems. Particularly this paper presents stochastic processes as examples of reliability systems for the support of the maintenance related decisions. We consider the simplest one-unit system with a negligible repair or replacement time, i.e., the unit is operating and is repaired or replaced at failure, where the time required for repair and replacement is negligible. When the repair or replacement is completed, the unit becomes as good as new and resumes operation. The stochastic modelling of recoverable systems constitutes an excellent method of supporting maintenance related decision-making processes and enables their more rational use.

A new incision for unilateral cleft lip repair developed using animated simulation of repair on computer

Directory of Open Access Journals (Sweden)

Sahay A

2007-01-01

Full Text Available Background: Unilateral cleft lip repair continues to leave behind some amount of dissatisfaction, as a scope for further improvement is always felt. Most surgeons do not like to deviate from the standard Millard′s/ triangular techniques, or their minor modifications, as no one likes to experiment on the face for fear of unfavourable outcomes. The computer can be utilized as a useful tool in the analysis and planning of surgery and new methods can be developed and attempted subsequently with greater confidence. Aim: We decided to see if an improved lip repair could be developed with the use of computers. Materials and Methods: Analysis of previous lip repairs was done to determine where an improvement was required. Movement of tissues, by simulating an ideal repair, using image warping software, on digital images of cleft lip was studied in animation sequences. A repair which could reproduce these movements was planned. A new incision emerged, which had combined the principles of Millard′s and Randall / Tennyson repairs, with additional features. The new method was performed on 30 cases. Conclusions: The results were encouraging as the shortcomings of these methods were minimized, and the advantages maximized.

30 CFR 57.14104 - Tire repairs.

Science.gov (United States)

2010-07-01

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

30 CFR 56.14104 - Tire repairs.

Science.gov (United States)

2010-07-01

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

Lichtenstein Mesh Repair (LMR) v/s Modified Bassini's Repair (MBR) + Lichtenstein Mesh Repair of Direct Inguinal Hernias in Rural Population - A Comparative Study.

Science.gov (United States)

Patil, Santosh M; Gurujala, Avinash; Kumar, Ashok; Kumar, Kuthadi Sravan; Mithun, Gorre

2016-02-01

Lichtenstein's tension free mesh hernioplasty is the commonly done open technique for inguinal hernias. As our hospital is in rural area, majority of patients are labourers, open hernias are commonly done. The present study was done by comparing Lichtenstein Mesh Repair (LMR) v/s Modified Bassini's repair (MBR) + Lichtenstein mesh repair (LMR) of direct Inguinal Hernias to compare the technique of both surgeries and its outcome like postoperative complications and recurrence rate. A comparative randomized study was conducted on patients reporting to MNR hospital, sangareddy with direct inguinal hernias. A total of fifty consecutive patients were included in this study of which, 25 patients were operated by LMR and 25 patients were operated by MBR+LMR and followed up for a period of two years. The outcomes of the both techniques were compared. Study involved 25 each of Lichtenstein's mesh repair (LMR) and modified bassini's repair (MBR) + LMR, over a period of 2 years. The duration of surgery for lichtenstein mesh repair is around 34.56 min compared to LMR+MBR, which is 47.56 min which was statistically significant (p-value is MBR group in POD 1, but not statistically significant (p-value is 0.0949) and from POD 7 the pain was almost similar in both groups. The recurrence rate is 2% for LMR and 0% for MBR+LMR. LMR+MBR was comparatively better than only LMR in all direct inguinal hernias because of low recurrence rate (0%) and low postoperative complications, which showed in our present study.

DNA repair and cancer

International Nuclear Information System (INIS)

Rathore, Shakuntla; Joshi, Pankaj Kumar; Gaur, Sudha

2012-01-01

DNA repair refers to a collection of processes by which a cell identifies and corrects damage to the DNA molecule that encode it's genome. In human cells, both normal metabolic activities and environmental factors such as UV light and radiation can cause DNA damage, resulting in as many one million individual molecular lesions per day. Many of these lesions cause structural damage to the DNA molecule and can alter or eliminate the cell's ability to transcribe the gene that the affected DNA encodes. Other lesions include potentially harmful mutation in cell's genome which affect the survival of it's daughter cells after it undergoes mitosis. As a consequence, the DNA repair process is constantly active as it responds to damage in the DNA structure. Inherited mutation that affect DNA repair genes are strongly associated with high cancer risks in humans. Hereditary non polyposis colorectal cancer (HNPCC) is strongly associated with specific mutation in the DNA mismatch repair pathway. BRCA1, BRCA2 two famous mutation conferring a hugely increased risk of breast cancer on carrier, are both associated with a large number of DNA repair pathway, especially NHEJ and homologous recombination. Cancer therapy procedures such as chemotherapy and radiotherapy work by overwhelming the capacity of the cell to repair DNA damage, resulting in cell death. Cells that are most rapidly dividing most typically cancer cells are preferentially affected. The side effect is that other non-cancerous but rapidly dividing cells such as stem cells in the bone marrow are also affected. Modern cancer treatment attempt to localize the DNA damage to cells and tissue only associated with cancer, either by physical means (concentrating the therapeutic agent in the region of the tumor) or by biochemical means (exploiting a feature unique to cancer cells in the body). (author)

Ship Repair Workflow Cost Model

National Research Council Canada - National Science Library

McDevitt, Mike

2003-01-01

The effects of intermittent work patterns and funding on the costs of ship repair and maintenance were modeled for the San Diego region in 2002 for Supervisor of Shipbuilding and Repair (SUPSHIP) San Diego...

Content-Related Repairing of Inconsistencies in Distributed Data

Institute of Scientific and Technical Information of China (English)

Yue-Feng Du; De-Rong Shen; Tie-Zheng Nie; Yue Kou; Ge Yu

2016-01-01

Conditional functional dependencies (CFDs) are a critical technique for detecting inconsistencies while they may ignore some potential inconsistencies without considering the content relationship of data. Content-related conditional functional dependencies (CCFDs) are a type of special CFDs, which combine content-related CFDs and detect potential inconsistencies by putting content-related data together. In the process of cleaning inconsistencies, detection and repairing are interactive: 1) detection catches inconsistencies, 2) repairing corrects caught inconsistencies while may bring new incon-sistencies. Besides, data are often fragmented and distributed into multiple sites. It consequently costs expensive shipment for inconsistencies cleaning. In this paper, our aim is to repair inconsistencies in distributed content-related data. We propose a framework consisting of an inconsistencies detection method and an inconsistencies repairing method, which work iteratively. The detection method marks the violated CCFDs for computing the inconsistencies which should be repaired preferentially. Based on the repairing-cost model presented in this paper, we prove that the minimum-cost repairing using CCFDs is NP-complete. Therefore, the repairing method heuristically repairs the inconsistencies with minimum cost. To improve the efficiency and accuracy of repairing, we propose distinct values and rules sequences. Distinct values make less data shipments than real data for communication. Rules sequences determine appropriate repairing sequences to avoid some incorrect repairs. Our solution is proved to be more effective than CFDs by empirical evaluation on two real-life datasets.

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

Science.gov (United States)

Hamlin, Larry

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

Pretreatment with mixed-function oxidase inducers increases the sensitivity of the hepatocyte/DNA repair assay

International Nuclear Information System (INIS)

Shaddock, J.G.; Heflich, R.H.; McMillan, D.C.; Hinson, J.A.; Casciano, D.A.

1989-01-01

A recent National Toxicology Program evaluation indicates that the rat hepatocyte/DNA repair assay has a high false-negative rate and that it is insensitive to some genotoxic hepatocarcinogens as well as other species and organ-specific carcinogens. In this study, the authors examined whether the sensitivity of the hepatocyte/DNA repair assay might be increased through animal pretreatment with various hepatic mixed-function oxidase inducers, i.e., Aroclor 1254, phenobarbital, and 3,3',4,4'-tetrachloroazobenzene (TCAB). The effects on unscheduled DNA synthesis (UDS), a measured of DNA damage and repair, were studied in cultures exposed to known and/or potential carcinogens that had been evaluated as negative or questionable or that produced conflicting results with hepatocytes isolated from uninduced animals. 4,4'-Oxydianiline, 1-nitropy-rene, and TCAB produced concentration-dependent increases in UDS in hepatocytes from rats pretreated with Aroclor 1254. 4,4'-Oxydianiline and TCAB also induced a dose-dependent increase in DNA repair in hepatocytes from rats pretreated with phenobarbital, whereas 1-nitropyrene was negative. These data indicate that the limited sensitivity to chemical carcinogens displayed by the hepatocyte/DNA repair assay may be increased by using hepatocytes isolated from animals exposed to hepatic mixed-function oxidase inducers

Pretreatment with mixed-function oxidase inducers increases the sensitivity of the hepatocyte/DNA repair assay

Energy Technology Data Exchange (ETDEWEB)

Shaddock, J.G.; Heflich, R.H.; McMillan, D.C.; Hinson, J.A.; Casciano, D.A. (National Center for Toxicological Research, Jefferson, AK (USA) Univ. of Arkansas for Medical Sciences, Little Rock (USA))

1989-01-01

A recent National Toxicology Program evaluation indicates that the rat hepatocyte/DNA repair assay has a high false-negative rate and that it is insensitive to some genotoxic hepatocarcinogens as well as other species and organ-specific carcinogens. In this study, the authors examined whether the sensitivity of the hepatocyte/DNA repair assay might be increased through animal pretreatment with various hepatic mixed-function oxidase inducers, i.e., Aroclor 1254, phenobarbital, and 3,3{prime},4,4{prime}-tetrachloroazobenzene (TCAB). The effects on unscheduled DNA synthesis (UDS), a measured of DNA damage and repair, were studied in cultures exposed to known and/or potential carcinogens that had been evaluated as negative or questionable or that produced conflicting results with hepatocytes isolated from uninduced animals. 4,4{prime}-Oxydianiline, 1-nitropy-rene, and TCAB produced concentration-dependent increases in UDS in hepatocytes from rats pretreated with Aroclor 1254. 4,4{prime}-Oxydianiline and TCAB also induced a dose-dependent increase in DNA repair in hepatocytes from rats pretreated with phenobarbital, whereas 1-nitropyrene was negative. These data indicate that the limited sensitivity to chemical carcinogens displayed by the hepatocyte/DNA repair assay may be increased by using hepatocytes isolated from animals exposed to hepatic mixed-function oxidase inducers.

The use of a cognitive task analysis-based multimedia program to teach surgical decision making in flexor tendon repair.

Science.gov (United States)

Luker, Kali R; Sullivan, Maura E; Peyre, Sarah E; Sherman, Randy; Grunwald, Tiffany

2008-01-01

The aim of this study was to compare the surgical knowledge of residents before and after receiving a cognitive task analysis-based multimedia teaching module. Ten plastic surgery residents were evaluated performing flexor tendon repair on 3 occasions. Traditional learning occurred between the first and second trial and served as the control. A teaching module was introduced as an intervention between the second and third trial using cognitive task analysis to illustrate decision-making skills. All residents showed improvement in their decision-making ability when performing flexor tendon repair after each surgical procedure. The group improved through traditional methods as well as exposure to our talk-aloud protocol (P > .01). After being trained using the cognitive task analysis curriculum the group displayed a statistically significant knowledge expansion (P multimedia surgical curriculum instruction achieved greater command of problem solving and are better equipped to make correct decisions in flexor tendon repair.

Section 609 Technician Training and Certification Programs

Science.gov (United States)

EPA-approved programs for technicians who service motor vehicle air conditioning (MVAC) systems. Any person who repairs or services a MVAC system for consideration must be certified under section 609 of the Clean Air Act by an EPA-approved program.

Mississippi Curriculum Framework for Diesel Equipment Repair & Service (Program CIP: 47.0605--Diesel Engine Mechanic & Repairer). Secondary Programs.

Science.gov (United States)

Mississippi Research and Curriculum Unit for Vocational and Technical Education, State College.

This document, which reflects Mississippi's statutory requirement that instructional programs be based on core curricula and performance-based assessment, contains outlines of the instructional units required in local instructional management plans and daily lesson plans for diesel engine mechanics I and II. Presented first are a program…

DNA repair in non-mammalian animals

International Nuclear Information System (INIS)

Mitani, Hiroshi

1984-01-01

Studies on DNA repair have been performed using microorganisms such as Escherichia coli and cultured human and mammalian cells. However, it is well known that cultured organic cells differ from each other in many respects, although DNA repair is an extremely fundamental function of organisms to protect genetic information from environmental mutagens such as radiation and 0 radicals developing in the living body. To answer the question of how DNA repair is different between the animal species, current studies on DNA repair of cultured vertebrate cells using the methods similar to those in mammalian experiments are reviewed. (Namekawa, K.)

Relationship of DNA repair and chromosome aberrations to potentially lethal damage repair in X-irradiated mammalian cells

International Nuclear Information System (INIS)

Fornace, A.J. Jr.; Nagasawa, H.; Little, J.B.

1980-01-01

By the alkaline elution technique, the repair of x-ray-induced DNA single strand breaks and DNA-protein cross-links was investigated in stationary phase, contact-inhibited mouse cells. During the first hour of repair, approximately 90% of x-ray induced single strand breaks were rejoined whereas most of the remaining breaks were rejoined more slowly during the next 5 h. The number of residual non-rejoined single strand breaks was approximately proportional to the x-ray dose at early repair times. DNA-protein cross-links were removed at a slower rate - T 1/2 approximately 10 to 12 h. Cells were subcultured at low density at various times after irradiation and scored for colony survival, and chromosome aberrations in the first mitosis after sub-culture. Both cell lethality and the frequency of chromosome aberrations decreased during the first several hours of repair, reaching a minimum level by 6 h; this decrease correlated temporally with the repair of the slowly rejoining DNA strand breaks. The possible relationship of DNA repair to changes in survival and chromosome aberrations is discussed

Repairing and Upgrading Your PC

CERN Document Server

Thompson, Robert

2009-01-01

Repairing and Upgrading Your PC delivers start-to-finish instructions, simple enough for even the most inexperienced PC owner, for troubleshooting, repairing, and upgrading your computer. Written by hardware experts Robert Bruce Thompson and Barbara Fritchman Thompson, this book covers it all: how to troubleshoot a troublesome PC, how to identify which components make sense for an upgrade, and how to tear it all down and put it back together. This book shows how to repair and upgrade all of your PC's essential components.

Base excision repair in Archaea: back to the future in DNA repair.

Science.gov (United States)

Grasso, Stefano; Tell, Gianluca

2014-09-01

Together with Bacteria and Eukarya, Archaea represents one of the three domain of life. In contrast with the morphological difference existing between Archaea and Eukarya, these two domains are closely related. Phylogenetic analyses confirm this evolutionary relationship showing that most of the proteins involved in DNA transcription and replication are highly conserved. On the contrary, information is scanty about DNA repair pathways and their mechanisms. In the present review the most important proteins involved in base excision repair, namely glycosylases, AP lyases, AP endonucleases, polymerases, sliding clamps, flap endonucleases, and ligases, will be discussed and compared with bacterial and eukaryotic ones. Finally, possible applications and future perspectives derived from studies on Archaea and their repair pathways, will be taken into account. Copyright © 2014 Elsevier B.V. All rights reserved.

Stripped-down DNA repair in a highly reduced parasite

Directory of Open Access Journals (Sweden)

Fast Naomi M

2007-03-01

Full Text Available Abstract Background Encephalitozoon cuniculi is a member of a distinctive group of single-celled parasitic eukaryotes called microsporidia, which are closely related to fungi. Some of these organisms, including E. cuniculi, also have uniquely small genomes that are within the prokaryotic range. Thus, E. cuniculi has undergone a massive genome reduction which has resulted in a loss of genes from diverse biological pathways, including those that act in DNA repair. DNA repair is essential to any living cell. A loss of these mechanisms invariably results in accumulation of mutations and/or cell death. Six major pathways of DNA repair in eukaryotes include: non-homologous end joining (NHEJ, homologous recombination repair (HRR, mismatch repair (MMR, nucleotide excision repair (NER, base excision repair (BER and methyltransferase repair. DNA polymerases are also critical players in DNA repair processes. Given the close relationship between microsporidia and fungi, the repair mechanisms present in E. cuniculi were compared to those of the yeast Saccharomyces cerevisiae to ascertain how the process of genome reduction has affected the DNA repair pathways. Results E. cuniculi lacks 16 (plus another 6 potential absences of the 56 DNA repair genes sought via BLASTP and PSI-BLAST searches. Six of 14 DNA polymerases or polymerase subunits are also absent in E. cuniculi. All of these genes are relatively well conserved within eukaryotes. The absence of genes is not distributed equally among the different repair pathways; some pathways lack only one protein, while there is a striking absence of many proteins that are components of both double strand break repair pathways. All specialized repair polymerases are also absent. Conclusion Given the large number of DNA repair genes that are absent from the double strand break repair pathways, E. cuniculi is a prime candidate for the study of double strand break repair with minimal machinery. Strikingly, all of the

Situation-dependent repair of DNA damage in yeast

International Nuclear Information System (INIS)

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

1985-01-01

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

Remote mechanized equipment for the repair and replacement of boiling water reactor recirculation loop piping

International Nuclear Information System (INIS)

Mauser, D.; Busch, D.F.

1983-01-01

Equipment has been assembled for the remote repair or replacement of boiling water reactor nuclear plant piping in the diameter range of 4 to 28 inches (10-71 cm). The objectives of this program were to produce high-quality pipe welds, reduce plant downtime, and reduce man-rem exposure. The repair strategy was to permit repair personnel to install and check out the repair subsystems and then leave the radiation zone allowing the operations to be conducted at a distance of up to 300 feet (91 m) from the operator. The complete repair system comprises subsystems for pipe severing, dimensional gaging, joint preparation, counterboring, welding, postweld nondestructive inspection (conceptual design), and audio, electronic, and visual monitoring of all operations. Components for all subsystems, excluding those for postweld nondestructive inspection, were purchased and modified as needed for integration into the repair system. Subsystems were designed for two sizes of Type 304 stainless steelpipe. For smaller, 12-inch-diameter (30.5 cm) pipe, severing is accomplished by a power hack saw and joint preparation and counterboring by an internally mounted lathe. The 22-inch-diameter (56 cm) pipe is severed, prepared, and counterbored using an externally mounted, single-point machining device. Dimensional gaging is performed to characterize the pipe geometry relative to a fixed external reference surface, allowing the placement of the joint preparation and the counterbore to be optimized. For both pipe sizes, a track-mounted gas tungsten-arc welding head with filler wire feed is used

Unanticipated Admission Following Outpatient Rotator Cuff Repair: An Analysis of 18,061 Cases.

Science.gov (United States)

Gil, Joseph A; Durand, Wesley M; Johnson, Joey P; Goodman, Avi D; Owens, Brett D; Daniels, Alan H

2018-05-01

The objective of this investigation was to examine the characteristics that place patients at risk for unanticipated inpatient admission after outpatient arthroscopic rotator cuff repair. This retrospective cohort study used the American College of Surgeons National Surgical Quality Improvement Program data sets from years 2012 to 2015. Patients were included in the study based on the presence of a primary Current Procedural Terminology code for rotator cuff repair (23410, 23412, 23420, and 29827). Only outpatient, nonemergent, and elective procedures performed on patients with American Society of Anesthesiologists classification of 4 or less were considered. The primary outcome variable was admission after outpatient surgery (defined as length of initial hospital stay >0). This study examined risk factors for unanticipated admission following rotator cuff repair, finding that age of 65 years or older, female sex, hypertension, body mass index of 35 kg/m 2 or greater, American Society of Anesthesiologists classification of 2 or greater, and open surgical technique were significant predictors of admission, whereas monitored anesthesia care and regional anesthesia were associated with decreased odds of admission. Identifying patients with these characteristics will be critical in risk adjusting the anticipated cost of the episode of care in outpatient rotator cuff repair. [Orthopedics. 2018; 41(3):164-168.]. Copyright 2018, SLACK Incorporated.

Cost-effectiveness of endovascular repair, open repair, and conservative management of splenic artery aneurysms

NARCIS (Netherlands)

Hogendoorn, Wouter; Lavida, Anthi; Hunink, M. G Myriam; Moll, Frans L.; Geroulakos, George; Muhs, Bart E.; Sumpio, Bauer E.

2015-01-01

Objective Open repair (OPEN) and conservative management (CONS) have been the treatments of choice for splenic artery aneurysms (SAAs) for many years. Endovascular repair (EV) has been increasingly used with good short-term results. In this study, we evaluated the cost-effectiveness of OPEN, EV, and

Recent advances in DNA repair and recombination.

Science.gov (United States)

Iwanejko, L A; Jones, N J

1998-09-11

The subjects of the talks at this 1-day DNA Repair Network meeting, held at City University, London on December 15, 1997, encompassed a range of topics and reflected some of the current areas of research in the United Kingdom. Topics included DNA double-strand break repair, V(D)J recombination, DNA ligases, the RecQ family of helicases and Bloom's syndrome, UVB and immunosuppression, the repair of oxidative damage and mismatch repair mechanisms.

Laparoscopic hernia repair and bladder injury.

Science.gov (United States)

Dalessandri, K M; Bhoyrul, S; Mulvihill, S J

2001-01-01

Bladder injury is a complication of laparoscopic surgery with a reported incidence in the general surgery literature of 0.5% and in the gynecology literature of 2%. We describe how to recognize and treat the injury and how to avoid the problem. We report two cases of bladder injury repaired with a General Surgical Interventions (GSI) trocar and a balloon device used for laparoscopic extraperitoneal inguinal hernia repair. One patient had a prior appendectomy; the other had a prior midline incision from a suprapubic prostatectomy. We repaired the bladder injury, and the patients made a good recovery. When using the obturator and balloon device, it is important to stay anterior to the preperitoneal space and bladder. Prior lower abdominal surgery can be considered a relative contraindication to extraperitoneal laparoscopic hernia repair. Signs of gas in the Foley bag or hematuria should alert the surgeon to a bladder injury. A one- or two-layer repair of the bladder injury can be performed either laparoscopically or openly and is recommended for a visible injury. Mesh repair of the hernia can be completed provided no evidence exists of urinary tract infection. A Foley catheter is placed until healing occurs.

Contact Dermatitis In Automobile Repair workers

Directory of Open Access Journals (Sweden)

Joshi M P

1997-01-01

Full Text Available Automobile repair workers are at risk of developing skin morbidity including occupational dermatoses because of their exposure to mineral oils, petroleum products and its derivatives and lubricating oil. This cross- sectional study was carried out at Maharashtra State Road Transport Corporation workshops in Nagpur city to investigate prevalence of skin morbidity including contact dermatitis in automobile repair workers. The study included 288 (49.9% automobile repair workers 180 (31.3% workshop office staff and 109 (18.8% divisional office employees. Dermatitis was the commonest skin morbidity in all the study subjects and it was significantly more prevalent in automobile repair workers. Folliculitis was detected in 13.2% of auto â€" repair workers and was not seen in the other two groups. Increasing trend of skin morbidity was correlated with the length of service of employees. Proper protective measures along with suitable washing facilities should be provided

Exploiting global information in complex network repair processes

Institute of Scientific and Technical Information of China (English)

Tianyu WANG; Jun ZHANG; Sebastian WANDELT

2017-01-01

Robustness of complex networks has been studied for decades,with a particular focus on network attack.Research on network repair,on the other hand,has been conducted only very lately,given the even higher complexity and absence of an effective evaluation metric.A recently proposed network repair strategy is self-healing,which aims to repair networks for larger compo nents at a low cost only with local information.In this paper,we discuss the effectiveness and effi ciency of self-healing,which limits network repair to be a multi-objective optimization problem and makes it difficult to measure its optimality.This leads us to a new network repair evaluation metric.Since the time complexity of the computation is very high,we devise a greedy ranking strategy.Evaluations on both real-world and random networks show the effectiveness of our new metric and repair strategy.Our study contributes to optimal network repair algorithms and provides a gold standard for future studies on network repair.

Repair of traumatized mammalian hair cells via sea anemone repair proteins.

Science.gov (United States)

Tang, Pei-Ciao; Smith, Karen Müller; Watson, Glen M

2016-08-01

Mammalian hair cells possess only a limited ability to repair damage after trauma. In contrast, sea anemones show a marked capability to repair damaged hair bundles by means of secreted repair proteins (RPs). Previously, it was found that recovery of traumatized hair cells in blind cavefish was enhanced by anemone-derived RPs; therefore, the ability of anemone RPs to assist recovery of damaged hair cells in mammals was tested here. After a 1 h incubation in RP-enriched culture media, uptake of FM1-43 by experimentally traumatized murine cochlear hair cells was restored to levels comparable to those exhibited by healthy controls. In addition, RP-treated explants had significantly more normally structured hair bundles than time-matched traumatized control explants. Collectively, these results indicate that anemone-derived RPs assist in restoring normal function and structure of experimentally traumatized hair cells of the mouse cochlea. © 2016. Published by The Company of Biologists Ltd.

DNA Damage Induced by Alkylating Agents and Repair Pathways

Science.gov (United States)

Kondo, Natsuko; Takahashi, Akihisa; Ono, Koji; Ohnishi, Takeo

2010-01-01

The cytotoxic effects of alkylating agents are strongly attenuated by cellular DNA repair processes, necessitating a clear understanding of the repair mechanisms. Simple methylating agents form adducts at N- and O-atoms. N-methylations are removed by base excision repair, AlkB homologues, or nucleotide excision repair (NER). O6-methylguanine (MeG), which can eventually become cytotoxic and mutagenic, is repaired by O6-methylguanine-DNA methyltransferase, and O6MeG:T mispairs are recognized by the mismatch repair system (MMR). MMR cannot repair the O6MeG/T mispairs, which eventually lead to double-strand breaks. Bifunctional alkylating agents form interstrand cross-links (ICLs) which are more complex and highly cytotoxic. ICLs are repaired by complex of NER factors (e.g., endnuclease xeroderma pigmentosum complementation group F-excision repair cross-complementing rodent repair deficiency complementation group 1), Fanconi anemia repair, and homologous recombination. A detailed understanding of how cells cope with DNA damage caused by alkylating agents is therefore potentially useful in clinical medicine. PMID:21113301

PTMC in post-MV repair status

Directory of Open Access Journals (Sweden)

Lachikarathman Devegowda

2016-09-01

Full Text Available MV repair in the rheumatic population is feasible with acceptable long-term results.1 Incidence of mitral stenosis (MS following mitral valve (MV repair for severe rheumatic mitral regurgitation (MR and usefulness of percutaneous transluminal mitral valvuloplasty (PTMC in these patients is not described in literature. We report a case of successful PTMC in severe MS following MV repair for severe rheumatic MR.

Hepatopancreaticobiliary Values after Thoracoabdominal Aneurysm Repair

OpenAIRE

Wu, Darrell; Coselli, Joseph S.; Johnson, Michael L.; LeMaire, Scott A.

2014-01-01

Background: After thoracoabdominal aortic aneurysm (TAAA) repair, blood tests assessing hepatopancreaticobiliary (HPB) organs commonly have abnormal results. The clinical significance of such abnormalities is difficult to determine because the expected postoperative levels have not been characterized. Therefore, we sought to establish expected trends in HPB laboratory values after TAAA repair. Methods: This 5-year study comprised 155 patients undergoing elective Crawford extent II TAAA repair...

Patient selection, echocardiographic screening and treatment strategies for interventional tricuspid repair using the edge-to-edge repair technique.

Science.gov (United States)

Hausleiter, Jörg; Braun, Daniel; Orban, Mathias; Latib, Azeem; Lurz, Philipp; Boekstegers, Peter; von Bardeleben, Ralph Stephan; Kowalski, Marek; Hahn, Rebecca T; Maisano, Francesco; Hagl, Christian; Massberg, Steffen; Nabauer, Michael

2018-04-24

Severe tricuspid regurgitation (TR) has long been neglected despite its well known association with mortality. While surgical mortality rates remain high in isolated tricuspid valve surgery, interventional TR repair is rapidly evolving as an alternative to cardiac surgery in selected patients at high surgical risk. Currently, interventional edge-to-edge repair is the most frequently applied technique for TR repair even though the device has not been developed for this particular indication. Due to the inherent differences in tricuspid and mitral valve anatomy and pathology, percutaneous repair of the tricuspid valve is challenging due to a variety of factors including the complexity and variability of tricuspid valve anatomy, echocardiographic visibility of the valve leaflets, and device steering to the tricuspid valve. Furthermore, it remains to be clarified which patients are suitable for a percutaneous tricuspid repair and which features predict a successful procedure. On the basis of the available experience, we describe criteria for patient selection including morphological valve features, a standardized process for echocardiographic screening, and a strategy for clip placement. These criteria will help to achieve standardization of valve assessment and the procedural approach, and to further develop interventional tricuspid valve repair using either currently available devices or dedicated tricuspid edge-to-edge repair devices in the future. In summary, this manuscript will provide guidance for patient selection and echocardiographic screening when considering edge-to-edge repair for severe TR.

Discrete time analysis of a repairable machine

OpenAIRE

Alfa, Attahiru Sule; Castro, I. T.

2002-01-01

We consider, in discrete time, a single machine system that operates for a period of time represented by a general distribution. This machine is subject to failures during operations and the occurrence of these failures depends on how many times the machine has previously failed. Some failures are repairable and the repair times may or may not depend on the number of times the machine was previously repaired. Repair times also have a general distribution. The operating times...

Telemetry Attributes Transfer Standard (TMATS) Handbook

Science.gov (United States)

2017-01-01

intermediate frequency IRIG Inter-Range Instrumentation Group kbps kilobits per second kHz kilohertz LHCP left hand circular polarization lsb...repeatedly to automate the setup of the station for a particular test. The receiver filters are defined below. The receiver intermediate

Autologous chondrocyte implantation: superior biologic properties of hyaline cartilage repairs.

Science.gov (United States)

Henderson, Ian; Lavigne, Patrick; Valenzuela, Herminio; Oakes, Barry

2007-02-01

Information regarding the quality of autologous chondrocyte implantation repair is needed to determine whether the current autologous chondrocyte implantation surgical technology and the subsequent biologic repair processes are capable of reliably forming durable hyaline or hyaline-like cartilage in vivo. We report and analyze the properties and qualities of autologous chondrocyte implantation repairs. We evaluated 66 autologous chondrocyte implantation repairs in 57 patients, 55 of whom had histology, indentometry, and International Cartilage Repair Society repair scoring at reoperation for mechanical symptoms or pain. International Knee Documentation Committee scores were used to address clinical outcome. Maximum stiffness, normalized stiffness, and International Cartilage Repair Society repair scoring were higher for hyaline articular cartilage repairs compared with fibrocartilage, with no difference in clinical outcome. Reoperations revealed 32 macroscopically abnormal repairs (Group B) and 23 knees with normal-looking repairs in which symptoms leading to arthroscopy were accounted for by other joint disorders (Group A). In Group A, 65% of repairs were either hyaline or hyaline-like cartilage compared with 28% in Group B. Autologous chondrocyte repairs composed of fibrocartilage showed more morphologic abnormalities and became symptomatic earlier than hyaline or hyaline-like cartilage repairs. The hyaline articular cartilage repairs had biomechanical properties comparable to surrounding cartilage and superior to those associated with fibrocartilage repairs.

Adaptive repair induced by small doses of γ radiation in repair-defective human cells

International Nuclear Information System (INIS)

Zasukhina, G.D.; L'vova, G.N.; Vasil'eva, I.M.; Sinel'shchikova, T.A.; Semyachkina, A.N.

1993-01-01

Adaptive repair induced by small doses of gamma radiation was studied in repair-defective xeroderma pigmentosum, gout, and homocystinuria cells. The adaptation of cells induced by small doses of radiation was estimated after subsequent exposure to gamma radiation, 4-nitroquinoline-1-oxide, and N-methyl-N-nitro-N-nitrosoguanidine by three methods: (1) by the reduction in DNA breaks; (2) by induction of resistant DNA synthesis; and (3) by increased reactivation of vaccinia virus. The three cell types in response to the three different mutagens revealed differences in the mechanism of cell defense in excision repair, in the adaptive response, and in Weigl reactivation

Repair-misrepair model of cell survival

International Nuclear Information System (INIS)

Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.

1980-01-01

During the last three years a new model, the repair-misrepair model (RMR) has been proposed, to interpret radiobiological experiments with heavy ions. In using the RMR model it became apparent that some of its features are suitable for handling the effects produced by a variety of environmental agents in addition to ionizing radiation. Two separate sequences of events are assumed to take place in an irradiated cell. The first sequence begins with an initial energy transfer consisting of ionizations and excitations, culminating via fast secondary physical and chemical processes in established macromolecular lesions in essential cell structures. The second sequence contains the responses of the cell to the lesions and consists of the processes of recognition and molecular repair. In normal cells there exists one repair process or at most a few enzymatic repair processes for each essential macromolecular lesion. The enzymatic repair processes may last for hours and minutes, and can be separated in time from the initial physicochemical and later genetic phases

Combining rhinoplasty with septal perforation repair.

Science.gov (United States)

Foda, Hossam M T; Magdy, Emad A

2006-11-01

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

Oxidative DNA damage & repair: An introduction.

Science.gov (United States)

Cadet, Jean; Davies, Kelvin J A

2017-06-01

This introductory article should be viewed as a prologue to the Free Radical Biology & Medicine Special Issue devoted to the important topic of Oxidatively Damaged DNA and its Repair. This special issue is dedicated to Professor Tomas Lindahl, co-winner of the 2015 Nobel Prize in Chemistry for his seminal discoveries in the area repair of oxidatively damaged DNA. In the past several years it has become abundantly clear that DNA oxidation is a major consequence of life in an oxygen-rich environment. Concomitantly, survival in the presence of oxygen, with the constant threat of deleterious DNA mutations and deletions, has largely been made possible through the evolution of a vast array of DNA repair enzymes. The articles in this Oxidatively Damaged DNA & Repair special issue detail the reactions by which intracellular DNA is oxidatively damaged, and the enzymatic reactions and pathways by which living organisms survive such assaults by repair processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Endogenous DNA Damage and Repair Enzymes

Directory of Open Access Journals (Sweden)

Arne Klungland

2016-06-01

Full Text Available Tomas Lindahl completed his medical studies at Karolinska Institute in 1970. Yet, his work has always been dedicated to unraveling fundamental mechanisms of DNA decay and DNA repair. His research is characterized with groundbreaking discoveries on the instability of our genome, the identification of novel DNA repair activities, the characterization of DNA repair pathways, and the association to diseases, throughout his 40 years of scientific career.

Nucleotide excision repair in differentiated cells

Energy Technology Data Exchange (ETDEWEB)

Wees, Caroline van der [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Jansen, Jacob [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Vrieling, Harry [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Laarse, Arnoud van der [Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Zeeland, Albert van [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Mullenders, Leon [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands)]. E-mail: l.mullenders@lumc.nl

2007-01-03

Nucleotide excision repair (NER) is the principal pathway for the removal of a wide range of DNA helix-distorting lesions and operates via two NER subpathways, i.e. global genome repair (GGR) and transcription-coupled repair (TCR). Although detailed information is available on expression and efficiency of NER in established mammalian cell lines, little is known about the expression of NER pathways in (terminally) differentiated cells. The majority of studies in differentiated cells have focused on repair of UV-induced cyclobutane pyrimidine dimers (CPD) and 6-4-photoproducts (6-4PP) because of the high frequency of photolesions at low level of toxicity and availability of sensitive technologies to determine photolesions in defined regions of the genome. The picture that emerges from these studies is blurred and rather complex. Fibroblasts and terminally differentiated myocytes of the rat heart display equally efficient GGR of 6-4PP but poor repair of CPD due to the absence of p48 expression. This repair phenotype is clearly different from human terminal differentiated neurons. Furthermore, both cell types were found to carry out TCR of CPD, thus mimicking the repair phenotype of established rodent cell lines. In contrast, in intact rat spermatogenic cells repair was very inefficient at the genome overall level and in transcriptionally active genes indicating that GGR and TCR are non-functional. Also, non-differentiated mouse embryonic stem (ES) cells exhibit low levels of NER after UV irradiation. However, the mechanisms that lead to low NER activity are clearly different: in differentiated spermatogenic cells differences in chromatin compaction and sequestering of NER proteins may underlie the lack of NER activity in pre-meiotic cells, whereas in non-differentiated ES cells NER is impaired by a strong apoptotic response.

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair.

Science.gov (United States)

Lightsey, Harry M; Kantrowitz, David E; Swindell, Hasani W; Trofa, David P; Ahmad, Christopher S; Lynch, T Sean

2018-02-01

The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Cross-sectional study. Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises. Fifteen protocols (43%) required completion of

An apology for primary repair of tetralogy of Fallot.

Science.gov (United States)

Van Arsdell, Glen; Yun, Tae-Jin

2005-01-01

The first repair of tetralogy of Fallot (TOF) was 50 years ago, so it would seem that the details for optimal management strategies would be clear. Timing of repair and operative repair strategy for TOF are still a source of debate. Varying institutions have published excellent outcomes with a primary repair strategy or a selective staged repair strategy. In this article, the current and historic strategy for repair of TOF at the Hospital for Sick Children in Toronto is delineated along with associated outcomes. Data from our institution indicate a clear survival advantage for primary repair of TOF.

Monogenic diseases of DNA repair

DEFF Research Database (Denmark)

Keijzers, Guido; Bakula, Daniela; Scheibye-Knudsen, Morten

2017-01-01

Maintaining the stability of the genome is essential for all organisms, and it is not surprising that damage to DNA has been proposed as an explanation for multiple chronic diseases.1-5 Conserving a pristine genome is therefore of central importance to our health. To overcome the genotoxic stress...... of a growing number of human diseases. Notably, many of these monogenic DNA-repair disorders display features of accelerated aging, supporting the notion that genome maintenance is a key factor for organismal longevity. This review focuses on the physiological consequences of loss of DNA repair, particularly...... in the context of monogenic DNA-repair diseases....

Radiation repair models for clinical application.

Science.gov (United States)

Dale, Roger G

2018-02-28

A number of newly emerging clinical techniques involve non-conventional patterns of radiation delivery which require an appreciation of the role played by radiation repair phenomena. This review outlines the main models of radiation repair, focussing on those which are of greatest clinical usefulness and which may be incorporated into biologically effective dose assessments. The need to account for the apparent "slowing-down" of repair rates observed in some normal tissues is also examined, along with a comparison of the relative merits of the formulations which can be used to account for such phenomena. Jack Fowler brought valuable insight to the understanding of radiation repair processes and this article includes reference to his important contributions in this area.

40 CFR 51.369 - Improving repair effectiveness.

Science.gov (United States)

2010-07-01

... vehicles that fail I/M tests. (a) Technical assistance. The oversight agency shall provide the repair industry with information and assistance related to vehicle inspection diagnosis and repair. (1) The agency... monitor the performance of individual motor vehicle repair facilities, and provide to the public at the...

Use of Drosophila to study DNA repair

International Nuclear Information System (INIS)

Boyd, J.B.; Harris, P.V.; Sakaguchi, K.

1988-01-01

This paper discusses Drosophila, the premier metazoan organism for analyzing many fundamental features of eukaryotic gene regulation. The authors present adaptations of several approaches for studying DNA repair to an analysis of repair-defective mutants in Drosophila. A current understanding of Drosophila DNA repair is described

Reprogramming Cells for Brain Repair

Directory of Open Access Journals (Sweden)

Randall D. McKinnon

2013-08-01

Full Text Available At present there are no clinical therapies that can repair traumatic brain injury, spinal cord injury or degenerative brain disease. While redundancy and rewiring of surviving circuits can recover some lost function, the brain and spinal column lack sufficient endogenous stem cells to replace lost neurons or their supporting glia. In contrast, pre-clinical studies have demonstrated that exogenous transplants can have remarkable efficacy for brain repair in animal models. Mesenchymal stromal cells (MSCs can provide paracrine factors that repair damage caused by ischemic injury, and oligodendrocyte progenitor cell (OPC grafts give dramatic functional recovery from spinal cord injury. These studies have progressed to clinical trials, including human embryonic stem cell (hESC-derived OPCs for spinal cord repair. However, ESC-derived allografts are less than optimal, and we need to identify a more appropriate donor graft population. The cell reprogramming field has developed the ability to trans-differentiate somatic cells into distinct cell types, a technology that has the potential to generate autologous neurons and glia which address the histocompatibility concerns of allografts and the tumorigenicity concerns of ESC-derived grafts. Further clarifying how cell reprogramming works may lead to more efficient direct reprogram approaches, and possibly in vivo reprogramming, in order to promote brain and spinal cord repair.

Recombinational repair: workshop summary

International Nuclear Information System (INIS)

Howard-Flanders, P.

1983-01-01

Recombinational repair may or may not be synonymous with postreplication repair. Considerable progress has been made in the study of the relevant enzymes, particularly those from bacteria. In this workshop we focus on the recombination enzyme RecA protein. What structural changes take place in the protein and in DNA during repair. How does homologous pairing take place. How is ATP hydrolysis coupled to the stand exchange reaction and the formation of heteroduplx DNA. Turning to another enzyme needed for certain kinds of bacterial recombination, we will ask whether the purified recB protein and recC protein complement each other and are sufficient for exonuclease V activity. In higher cells, we would like to know whether sister exchanges, which occur in bacteria after uv irradiation, are also seen in animal cells

Electron Transfer Mechanisms of DNA Repair by Photolyase

Science.gov (United States)

Zhong, Dongping

2015-04-01

Photolyase is a flavin photoenzyme that repairs two DNA base damage products induced by ultraviolet (UV) light: cyclobutane pyrimidine dimers and 6-4 photoproducts. With femtosecond spectroscopy and site-directed mutagenesis, investigators have recently made significant advances in our understanding of UV-damaged DNA repair, and the entire enzymatic dynamics can now be mapped out in real time. For dimer repair, six elementary steps have been characterized, including three electron transfer reactions and two bond-breaking processes, and their reaction times have been determined. A unique electron-tunneling pathway was identified, and the critical residues in modulating the repair function at the active site were determined. The dynamic synergy between the elementary reactions for maintaining high repair efficiency was elucidated, and the biological nature of the flavin active state was uncovered. For 6-4 photoproduct repair, a proton-coupled electron transfer repair mechanism has been revealed. The elucidation of electron transfer mechanisms and two repair photocycles is significant and provides a molecular basis for future practical applications, such as in rational drug design for curing skin cancer.

Meningocele repair

Science.gov (United States)

... is surgery to repair birth defects of the spine and spinal membranes. Meningocele and myelomeningocele ... is covered by a sterile dressing. Your child may then be transferred to a neonatal intensive ...

Arthroscopic Hip Labral Repair: The Iberian Suture Technique

OpenAIRE

Stubbs, Allston J.; Andersen, Jason S.; Mannava, Sandeep; Wooster, Benjamin M.; Howse, Elizabeth A.; Winter, S. Bradley

2014-01-01

Arthroscopic hip labral repair has beneficial short-term outcomes; however, debate exists regarding ideal surgical labral repair technique. This technical note presents an arthroscopic repair technique that uses intrasubstance labral suture passage to restore the chondrolabral interface. This “Iberian suture technique” allows for an anatomic repair while posing minimal risk of damage to the labral and chondral tissues.

DNA repair and radiation sensitivity in mammalian cells

International Nuclear Information System (INIS)

Chen, D.J.C.; Stackhouse, M.; Chen, D.S.

1993-01-01

Ionizing radiation induces various types of damage in mammalian cells including DNA single-strand breaks, DNA double-strand breaks (DSB), DNA-protein cross links, and altered DNA bases. Although human cells can repair many of these lesions there is little detailed knowledge of the nature of the genes and the encoded enzymes that control these repair processes. We report here on the cellular and genetic analyses of DNA double-strand break repair deficient mammalian cells. It has been well established that the DNA double-strand break is one of the major lesions induced by ionizing radiation. Utilizing rodent repair-deficient mutant, we have shown that the genes responsible for DNA double-strand break repair are also responsible for the cellular expression of radiation sensitivity. The molecular genetic analysis of DSB repair in rodent/human hybrid cells indicate that at least 6 different genes in mammalian cells are responsible for the repair of radiation-induced DNA double-strand breaks. Mapping and the prospect of cloning of human radiation repair genes are reviewed. Understanding the molecular and genetic basis of radiation sensitivity and DNA repair in man will provide a rational foundation to predict the individual risk associated with radiation exposure and to prevent radiation-induced genetic damage in the human population

Repair of single-strand breaks induced in the DNA of Proteus mirabilis by excision repair after UV-irradiation

International Nuclear Information System (INIS)

Stoerl, K.; Mund, C.

1977-01-01

Single-strand breaks have been produced in the DNA of P. mirabilis after UV-irradiation in dependence on the incident UV-doses. It has been found that there exists a discrepancy between the single-strand breaks estimated from sedimentation in alkaline sucrose gradients and the expected single-strand breaks approximated from measurements of dimer excision. The low number in incision breaks observed by sedimentation experiments is an indication that the cells are able to repair the excision-induced breaks as fast as they are formed. Toluenized cells have been used for investigation of the incision step independently of subsequent repair processes. In presence of NMN the appearance of more single-strand breaks in the DNA has been observed. Furthermore, the number of incision breaks in toluenized cells increased in presence of exogenous ATP. The completion of the excision repair process has been investigated by observing the rejoining of incision breaks. After irradiation with UV-doses higher than approximately 240 erg/mm 2 the number of single-strand breaks remaining unrepaired in the DNA increased. Studies of the influence of nutrition conditions on the repair process have shown approximately the same capacity for repair of single-strand breaks in growth medium as well as in buffer. Progress in the excision repair was also followed by investigation of the DNA synthesized at the template-DNA containing the pyrimidine dimers. In comparison with E. coli, P. mirabilis showed a somewhat lower efficiency for the repair of single-strand breaks during the excision repair. (author)

Higher-order chromatin structure in DSB induction, repair and misrepair

Czech Academy of Sciences Publication Activity Database

Falk, Martin; Lukášová, Emilie; Kozubek, Stanislav

2010-01-01

Roč. 704, 1-3 (2010), s. 88-100 ISSN 1383-5742 R&D Projects: GA MŠk ME 919; GA AV ČR(CZ) IAA500040802; GA AV ČR(CZ) 1QS500040508 Grant - others:GA MŠk(CZ) LC535 Program:LC Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA double strand breaks * DSB repair * higher-order chromatin structure Subject RIV: BO - Biophysics Impact factor: 8.741, year: 2010

48 CFR 1371.118 - Changes-ship repair.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause...

27 CFR 555.216 - Repair of magazines.

Science.gov (United States)

2010-04-01

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

[Constitutional mismatch repair deficiency syndrome

NARCIS (Netherlands)

Jongmans, M.C.J.; Gidding, C.E.M.; Loeffen, J.; Wesseling, P.; Mensenkamp, A.; Hoogerbrugge, N.

2015-01-01

BACKGROUND: Constitutional mismatch repair deficiency (CMMR-D) syndrome is characterised by a significantly increased risk for developing cancer in childhood. It arises when both parents have a mutation in the same mismatch repair gene and pass it on to their child. CASE DESCRIPTION: An 8-year-old

Male Fertility After Inguinal Hernia Mesh Repair

DEFF Research Database (Denmark)

Kohl, Andreas Pagh; Andresen, Kristoffer; Rosenberg, Jacob

2017-01-01

OBJECTIVE:: To determine whether patients who receive an inguinal hernia repair father the same number of children as the background population. BACKGROUND:: Although the effect of inguinal hernia repair on male fertility has previously been investigated through indirect measures, no previous...... studies have evaluated the final measure of male fertility, which is the number of children fathered by patients. METHODS:: Prospectively collected data on 32,621 male patients between the ages of 18 and 55 years who received 1 or more inguinal hernia repairs during the years 1998 to 2012 were found in 5...... hernia repair using Lichtenstein technique or laparoscopic approach did not father fewer children than expected. Thus, inguinal hernia repair using Lichtenstein or laparoscopic approach did not impair male fertility....

Diverless pipeline repair system for deep water

Energy Technology Data Exchange (ETDEWEB)

Spinelli, Carlo M. [Eni Gas and Power, Milan (Italy); Fabbri, Sergio; Bachetta, Giuseppe [Saipem/SES, Venice (Italy)

2009-07-01

SiRCoS (Sistema Riparazione Condotte Sottomarine) is a diverless pipeline repair system composed of a suite of tools to perform a reliable subsea pipeline repair intervention in deep and ultra deep water which has been on the ground of the long lasting experience of Eni and Saipem in designing, laying and operating deep water pipelines. The key element of SiRCoS is a Connection System comprising two end connectors and a repair spool piece to replace a damaged pipeline section. A Repair Clamp with elastomeric seals is also available for pipe local damages. The Connection System is based on pipe cold forging process, consisting in swaging the pipe inside connectors with suitable profile, by using high pressure seawater. Three swaging operations have to be performed to replace the damaged pipe length. This technology has been developed through extensive theoretical work and laboratory testing, ending in a Type Approval by DNV over pipe sizes ranging from 20 inches to 48 inches OD. A complete SiRCoS system has been realised for the Green Stream pipeline, thoroughly tested in workshop as well as in shallow water and is now ready, in the event of an emergency situation.The key functional requirements for the system are: diverless repair intervention and fully piggability after repair. Eni owns this technology and is now available to other operators under Repair Club arrangement providing stand-by repair services carried out by Saipem Energy Services. The paper gives a description of the main features of the Repair System as well as an insight into the technological developments on pipe cold forging reliability and long term duration evaluation. (author)

Canadian company innovates dam repair

International Nuclear Information System (INIS)

Anon.

2000-01-01

Successful repair without any downtime, of the Sabana Yegua power and irrigation structure in the western Dominican Republic by Aquatic Sciences Ltd., a St. Catherine, Ontario-based underwater specialist company, is discussed. The structure was damaged by Hurricane George last when when rising water levels damaged a major valve in the control gate chamber. The repair strategy designed by Aquatic Sciences used a remotely operated vehicle with a mechanical arm for minor tasks which placed a specially-made plug into the inlet pipe. The work was completed in one week, saving the utility company a great deal of money by making it possible to make the repairs remotely in the gate chamber without having to drain the tunnel, as would have been necessary had the repair been completed manually. The remotely operated vehicles use a scanning sonar as well as light to find their way. They are particularly well adapted to work underwater under low-visibility conditions

Connecting inventory control and repair shop control : a differentiated control structure for repairable spare parts

NARCIS (Netherlands)

Driessen, M.A.; Rustenburg, W.D.; Houtum, van G.J.J.A.N.; Wiers, V.C.S.

2014-01-01

This paper presents a control structure for integrating decisions on spare parts inventory control and the control of repair shops for maintenance spare parts. A dierentiated control structure is proposed for the various repair shop types recognized in practice. Decisions functions are mapped and

Lichtenstein Mesh Repair (LMR) v/s Modified Bassini’s Repair (MBR) + Lichtenstein Mesh Repair of Direct Inguinal Hernias in Rural Population – A Comparative Study

Science.gov (United States)

Patil, Santosh M; Kumar, Ashok; Kumar, Kuthadi Sravan; Mithun, Gorre

2016-01-01

Introduction Lichtenstein’s tension free mesh hernioplasty is the commonly done open technique for inguinal hernias. As our hospital is in rural area, majority of patients are labourers, open hernias are commonly done. The present study was done by comparing Lichtenstein Mesh Repair (LMR) v/s Modified Bassini’s repair (MBR) + Lichtenstein mesh repair (LMR) of direct Inguinal Hernias to compare the technique of both surgeries and its outcome like postoperative complications and recurrence rate. Materials and Methods A comparative randomized study was conducted on patients reporting to MNR hospital, sangareddy with direct inguinal hernias. A total of fifty consecutive patients were included in this study of which, 25 patients were operated by LMR and 25 patients were operated by MBR+LMR and followed up for a period of two years. The outcomes of the both techniques were compared. Results Study involved 25 each of Lichtenstein’s mesh repair (LMR) and modified bassini’s repair (MBR) + LMR, over a period of 2 years. The duration of surgery for lichtenstein mesh repair is around 34.56 min compared to LMR+MBR, which is 47.56 min which was statistically significant (p-value is MBR group in POD 1, but not statistically significant (p-value is 0.0949) and from POD 7 the pain was almost similar in both groups. The recurrence rate is 2% for LMR and 0% for MBR+LMR. Conclusion LMR+MBR was comparatively better than only LMR in all direct inguinal hernias because of low recurrence rate (0%) and low postoperative complications, which showed in our present study. PMID:27042517

Hepatopancreaticobiliary Values after Thoracoabdominal Aneurysm Repair

Science.gov (United States)

Wu, Darrell; Coselli, Joseph S.; Johnson, Michael L.; LeMaire, Scott A.

2014-01-01

Background: After thoracoabdominal aortic aneurysm (TAAA) repair, blood tests assessing hepatopancreaticobiliary (HPB) organs commonly have abnormal results. The clinical significance of such abnormalities is difficult to determine because the expected postoperative levels have not been characterized. Therefore, we sought to establish expected trends in HPB laboratory values after TAAA repair. Methods: This 5-year study comprised 155 patients undergoing elective Crawford extent II TAAA repair. In accordance with a prospective study protocol, all repairs involved left-sided heart bypass, selective visceral perfusion, and cold renal perfusion. Blood levels of aspartate transaminase (AST), alanine transaminase (ALT), γ-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), total bilirubin, amylase, and lipase were measured before TAAA repair and for 7 days afterward. Ratios between postoperative and baseline levels were compared for each time point with 95% confidence intervals. Results: Temporal patterns for the laboratory values varied greatly. Amylase, lipase, and AST underwent significant early increases before decreasing to preoperative levels. LDH increased immediately and remained significantly elevated, whereas ALT increased more gradually. GGT remained near baseline through postoperative day 4, and then increased to more than twice baseline. Total bilirubin never differed significantly from baseline. After adjusted analysis, the ischemic time predicted the maximum AST, lipase, GGT, and LDH values. Conclusions: Although most HPB laboratory values increase significantly after elective TAAA repair, the temporal trends for different values vary substantially. The ischemic time predicts the maximum AST, lipase, GGT, and LDH levels. These trends should be considered when laboratory values are assessed after TAAA repair. PMID:26798731

Case study : a transformer repair facility

Energy Technology Data Exchange (ETDEWEB)

Jerade, L. [Jacques Whitford Environment Ltd., Vancouver, BC (Canada)

2006-07-01

Polychlorinated biphenyls (PCBs) are synthetic chemical compounds consisting of chlorine, carbon and hydrogen. They are very stable, fire resistant, do not conduct electricity and have low volatility at normal temperatures. They were mainly used as a cooling and insulating fluid for industrial transformers and capacitors. Some of the same properties that made PCBs so widely used, also make them environmentally hazardous, especially their extreme resistance to chemical and biological breakdown by natural processes in the environment. Typical chemicals associated with the presence of PCB oils are chlorobenzene, lead, xylene, and petroleum hydrocarbons. A case study of a transformer repair facility was discussed along with its soil and groundwater remediation. This presentation discussed the delineation program for the site which operated as a repair facility of PCB-containing transformers from 1968 until 1998. The property was bought by Siemens Canada Ltd. in 1998 and was sold in 2004. As part of the purchasing agreement, a Certificate of Compliance from the British Columbia Ministry of Environment was required. Remediation work was therefore needed. The presentation also covered: zones of contamination and contaminants of concern, soil impacts, groundwater impacts, and an evaluation of remediation options. In-situ treatment of soil with hydrogen peroxide and the selected remedial option were discussed. A soil economic analysis was also conducted. Last, challenges, solutions, and conclusions were presented. tabs., figs.

Impact of Methane Leak Detection and Repair Programs: Determining Pre- and Post-Survey Emissions Profiles

Science.gov (United States)

Roda-Stuart, D. J.; Ravikumar, A. P.; Brandt, A. R.

2017-12-01

Upstream production sites contribute 66 percent of methane emissions from natural gas systems [1]. Being a major greenhouse gas, many states and national governments are developing policies to reduce methane emissions. Recent policies to address this issue have focused on periodic leak detection and repair (LDAR) surveys at oil and gas facilities [2]. Development of effective LDAR surveys is complicated by two things. First, available empirical data makes it difficult to say anything definitive about which facilities or equipment are most prone to leakage. Second, there has been little research done on post-LDAR emissions profiles and the time evolution of leaks, two measures that would influence survey effectiveness and cost. In this work, we present data from LDAR operations conducted at upstream facilities of a Canadian natural gas producer. Surveys were done by an outside contractor using a FLIR optical gas imaging camera. Twenty-two well pads, five processing plants, and three compressor stations were surveyed, of which four, two, and one, respectively, were revisited. We examine the persistence of leaks over time periods ranging from 6 months to 15 months following the initial LDAR survey. Developing pre- and post-survey emission factors and distributions can help inform survey schedules and help update and monitor mitigation targets. Furthermore, we analyze the effect of weather conditions, survey frequency, and operational characteristics of equipment on the effectiveness of the LDAR program. For instance, we find that a survey done at the commissioning of a gas processing plant yields both safety and emissions reduction benefits. Using leak frequency distributions, we identify components and equipment that require more frequent and targeted surveying. Insights from this study can assist businesses and policy makers develop methane mitigation policies aimed at maximizing the marginal benefits of LDAR programs. [1] Inventory of U.S. Greenhouse Gas Emissions

Repairing liner of the reactor; Reparacion del liner del reactor

Energy Technology Data Exchange (ETDEWEB)

Aguilar H, F [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2001-07-15

Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

Nucleotide excision repair in yeast

NARCIS (Netherlands)

Eijk, Patrick van

2012-01-01

Nucleotide Excision Repair (NER) is a conserved DNA repair pathway capable of removing a broad spectrum of DNA damage. In human cells a defect in NER leads to the disorder Xeroderma pigmentosum (XP). The yeast Saccharomyces cerevisiae is an excellent model organism to study the mechanism of NER. The

Repair of DNA damage in Deinococcus radiodurans

International Nuclear Information System (INIS)

Evans, D.M.

1984-01-01

The repair of DNA lesions in Deinococcus radiodurans was examined with particular reference to DNA excision repair of ultraviolet light (UV) induced pyrimidine dimers. The characteristics of excision repair via UV endonucleases α and β in vivo varied with respect to (a) the substrate range of the enzymes, (b) the rate of repair of DNA damage (c) the requirement for a protein synthesised in response to DNA damage to attenuate exonuclease action at repairing regions. UV endonuclease α is postulated to incise DNA in a different manner from UV endonuclease β thus defining the method of subsequent repair. Several DNA damage specific endonuclease activities independent of α and β are described. Mutations of the uvsA, uvsF and uvsG genes resulted in an increase in single-strand breaks in response to DNA damage producing uncontrolled DNA degradation. Evidence is presented that these genes have a role in limiting the access of UV endonuclease β to DNA lesions. uvsF and uvsG are also shown to be linked to the mtoA gene. Mutation of uvsH and reo-1 produces further distinct phenotypes which are discussed. An overall model of excision repair of DNA damage in Deinococcus radiodurans is presented. (author)

Web-ADARE: A Web-Aided Data Repairing System

KAUST Repository

Gu, Binbin

2017-03-08

Data repairing aims at discovering and correcting erroneous data in databases. In this paper, we develop Web-ADARE, an end-to-end web-aided data repairing system, to provide a feasible way to involve the vast data sources on the Web in data repairing. Our main attention in developing Web-ADARE is paid on the interaction problem between web-aided repairing and rule-based repairing, in order to minimize the Web consultation cost while reaching predefined quality requirements. The same interaction problem also exists in crowd-based methods but this is not yet formally defined and addressed. We first prove in theory that the optimal interaction scheme is not feasible to be achieved, and then propose an algorithm to identify a scheme for efficient interaction by investigating the inconsistencies and the dependencies between values in the repairing process. Extensive experiments on three data collections demonstrate the high repairing precision and recall of Web-ADARE, and the efficiency of the generated interaction scheme over several baseline ones.

Web-ADARE: A Web-Aided Data Repairing System

KAUST Repository

Gu, Binbin; Li, Zhixu; Yang, Qiang; Xie, Qing; Liu, An; Liu, Guanfeng; Zheng, Kai; Zhang, Xiangliang

2017-01-01

Data repairing aims at discovering and correcting erroneous data in databases. In this paper, we develop Web-ADARE, an end-to-end web-aided data repairing system, to provide a feasible way to involve the vast data sources on the Web in data repairing. Our main attention in developing Web-ADARE is paid on the interaction problem between web-aided repairing and rule-based repairing, in order to minimize the Web consultation cost while reaching predefined quality requirements. The same interaction problem also exists in crowd-based methods but this is not yet formally defined and addressed. We first prove in theory that the optimal interaction scheme is not feasible to be achieved, and then propose an algorithm to identify a scheme for efficient interaction by investigating the inconsistencies and the dependencies between values in the repairing process. Extensive experiments on three data collections demonstrate the high repairing precision and recall of Web-ADARE, and the efficiency of the generated interaction scheme over several baseline ones.

Aircraft Propeller Hub Repair

Energy Technology Data Exchange (ETDEWEB)

Muth, Thomas R [ORNL; Peter, William H [ORNL

2015-02-13

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

Robotic Inguinal Hernia Repair: Technique and Early Experience.

Science.gov (United States)

Arcerito, Massimo; Changchien, Eric; Bernal, Oscar; Konkoly-Thege, Adam; Moon, John

2016-10-01

Laparoscopic inguinal hernia repair has been shown to have multiple advantages compared with open repair such as less postoperative pain and earlier resume of daily activities with a comparable recurrence rate. We speculate robotic inguinal hernia repair may yield equivalent benefits, while providing the surgeon added dexterity. One hundred consecutive robotic inguinal hernia repairs with mesh were performed with a mean age of 56 years (25-96). Fifty-six unilateral hernias and 22 bilateral hernias were repaired amongst 62 males and 16 females. Polypropylene mesh was used for reconstruction. All but, two patients were completed robotically. Mean operative time was 52 minutes per hernia repair (45-67). Five patients were admitted overnight based on their advanced age. Regular diet was resumed immediately. Postoperative pain was minimal and regular activity was achieved after an average of four days. One patient recurred after three months in our earlier experience and he was repaired robotically. Mean follow-up time was 12 months. These data, compared with laparoscopic approach, suggest similar recurrence rates and postoperative pain. We believe comparative studies with laparoscopic approach need to be performed to assess the role robotic surgery has in the treatment of inguinal hernia repair.

The effect of DNA repair defects on reproductive performance in nucleotide excision repair (NER) mouse models: an epidemiological approach

NARCIS (Netherlands)

Tsai, P.S.; Nielen, M.; Horst, G.T.J. van der; Colenbrander, B.; Heesterbeek, J.A.P.; Fentener van Vlissingen, J.M.

2005-01-01

In this study, we used an epidemiological approach to analyze an animal database of DNA repair deficient mice on reproductive performance in five Nucleotide Excision Repair (NER) mutant mouse models on a C57BL/6 genetic background, namely CSA, CSB, XPA, XPC [models for the human DNA repair disorders

On the optimal degree of imperfect repair

International Nuclear Information System (INIS)

Finkelstein, Maxim

2015-01-01

A simple cost-wise comparison between the minimal and perfect repair of a system is discussed first using a relevant example. The main focus of this note, however, is on imperfect (general) repair. The best repair for our system in this case is defined as the one that corresponds to the optimal level (extent) of repair actions that minimize the long-run expected cost per unit of time. This complex optimization problem is considered for a specific imperfect repair model (Kijima II), using the developed earlier asymptotic approach to the corresponding virtual age modelling. It is shown that the optimal solution exists when the failure rate of a system tends to infinity as t tends to infinity and the corresponding cost function decreases sufficiently fast. An example illustrating the optimization procedure is considered

Repair of DNA in xeroderma pigmentosum conjunctiva

International Nuclear Information System (INIS)

Newsome, D.A.; Kraemer, K.H.; Robbins, J.H.

1975-01-01

Xeroderma pigmentosum (XP) is an autosomal recessive disease with tumor formation on sun-exposed areas of the skin and eyes. Cells from most XP patients are deficient in repairing DNA damaged by ultraviolet (uv) light as shown by a reduced rate of tritiated thymidine (3HTdR) incorporation during their DNA repair synthesis. We have studied such repair synthesis in conjunctival cells from an XP patient with a conjunctival epithelioma and from normal cadaver conjunctiva. Cultured conjunctival cells were irradiated with uv light and then incubated with 3HTdR. Autoradiograms were prepared and showed that uv radiation induced a considerably slower rate of DNA repair synthesis in the XP cells than in normal cells. Many of the ocular abnormalities of XP, including tumor formation, may be the result of this defective DNA repair process

The journey of DNA repair

OpenAIRE

Saini, Natalie

2015-01-01

21 years ago, the DNA Repair Enzyme was declared “Molecule of the Year”. Today, we are celebrating another “year of repair”, with the 2015 Nobel Prize in Chemistry being awarded to Aziz Sancar, Tomas Lindahl and Paul Modrich for their collective work on the different DNA repair pathways.

DNA excision repair in permeable human fibroblasts

International Nuclear Information System (INIS)

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

1983-01-01

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

Celebrating DNA's Repair Crew.

Science.gov (United States)

Kunkel, Thomas A

2015-12-03

This year, the Nobel Prize in Chemistry has been awarded to Tomas Lindahl, Aziz Sancar, and Paul Modrich for their seminal studies of the mechanisms by which cells from bacteria to man repair DNA damage that is generated by normal cellular metabolism and stress from the environment. These studies beautifully illustrate the remarkable power of DNA repair to influence life from evolution through disease susceptibility. Copyright © 2015 Elsevier Inc. All rights reserved.

Current concepts in repair of extremity venous injury.

Science.gov (United States)

Williams, Timothy K; Clouse, W Darrin

2016-04-01

Extremity venous injury management remains controversial. The purpose of this communication is to offer perspective as well as experiential and technical insight into extremity venous injury repair. Available literature is reviewed and discussed. Historical context is provided. Indication, the decision process for repair, including technical conduct, is delineated. In particular, the authors' experiences in both civilian and wartime injury are used for perspective. Extremity venous injury repair was championed within data from the Vietnam Vascular Registry. However, patterns of extremity venous injury differ between combat and civilian settings. Since Vietnam, civilian descriptive series opine the benefits and potential complications associated with both venous injury repair and ligation. These surround extremity edema, chronic venous insufficiency, thromboembolism, and limb loss. Whereas no clear superiority in either approach has been identified to date, there appears to be no increased risk of pulmonary embolism or chronic venous changes with repair. Newer data from the wars in Iraq and Afghanistan and meta-analysis have reinforced this and also have suggested limb salvage benefit for extremity venous repair in combined arterial and venous injuries in modern settings. The patient's physiologic state and associated injury drive five triage categories suggesting vein injury management. Vein repair thrombosis occurs in a significant proportion, yet many recanalize and possibly have a positive impact on limb venous return. Further, early decompression favors reduced blood loss, acute edema, and inflammation, supporting collateral development. Large soft tissue injury minimizing collateral capacity increases the importance of repair. Constructs of repair are varied with modest differences in patency. Venous shunting is feasible, but specific roles remain nebulous. An aggressive posture toward extremity venous injury repair seems justified today because of the likely

Human diseases associated with defective DNA repair

International Nuclear Information System (INIS)

Friedberg, E.C.; Ehmann, U.K.; Williams, J.I.

1979-01-01

The observations on xeroderma pigmentosum (XP) cells in culture were the first indications of defective DNA repair in association with human disease. Since then, a wealth of information on DNA repair in XP, and to a lesser extent in other diseases, has accumulated in the literature. Rather than clarifying the understanding of DNA repair mechanisms in normal cells and of defective DNA repair in human disease, the literature suggests an extraordinary complexity of both of the phenomena. In this review a number of discrete human diseases are considered separately. An attempt was made to systematically describe the pertinent clinical features and cellular and biochemical defects in these diseases, with an emphasis on defects in DNA metabolism, particularly DNA repair. Wherever possible observations have been correlated and unifying hypotheses presented concerning the nature of the basic defect(s) in these diseases. Discussions of the following diseases are presented: XP, ataxia telangiectasia; Fanconi's anemia; Hutchinson-Gilford progeria syndrome; Bloom's syndrome, Cockayne's syndrome; Down's syndrome; retinoblastoma; chronic lymphocytic leukemia; and other miscellaneous human diseases with possble DNA repair defects

Energy and Technology Review: Unlocking the mysteries of DNA repair

Energy Technology Data Exchange (ETDEWEB)

Quirk, W.A.

1993-04-01

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

Analysis of mutagenic DNA repair in a thermoconditional mutant of Saccharomyces cerevisiae. IV. Influence of DNA replication and excision repair on REV2 dependent UV-mutagenesis and repair

Energy Technology Data Exchange (ETDEWEB)

Siede, W.; Eckardt, F.

1986-01-01

A double mutant being thermoconditionally defective in mutation induction as well as in repair of pre-lethal UV-induced DNA damage (rev2ts) and deficient in excision repair (rad3-2) was studied in temperature-shift experiments. The influence of inhibitors of DNA replication (hydroxyurea, aphidicolin) was determined. Additionally, an analysis of the dose-response pattern of mutation induction (mutation kinetics) at several ochre alleles was carried out. It was concluded that the UV-inducible REV2 dependent mutagenic repair process is not induced in excision-deficient cells. In excision-deficient cells, REV2 dependent mutation fixation is slow and mostly post-replicative though not dependent on DNA replication. The REV2 mediated mutagenic process could be separated from the repair function.

DNA repair: Dynamic defenders against cancer and aging

Energy Technology Data Exchange (ETDEWEB)

Fuss, Jill O.; Cooper, Priscilla K.

2006-04-01

You probably weren't thinking about your body's cellular DNA repair systems the last time you sat on the beach in the bright sunshine. Fortunately, however, while you were subjecting your DNA to the harmful effects of ultraviolet light, your cells were busy repairing the damage. The idea that our genetic material could be damaged by the sun was not appreciated in the early days of molecular biology. When Watson and Crick discovered the structure of DNA in 1953 [1], it was assumed that DNA is fundamentally stable since it carries the blueprint of life. However, over 50 years of research have revealed that our DNA is under constant assault by sunlight, oxygen, radiation, various chemicals, and even our own cellular processes. Cleverly, evolution has provided our cells with a diverse set of tools to repair the damage that Mother Nature causes. DNA repair processes restore the normal nucleotide sequence and DNA structure of the genome after damage [2]. These responses are highly varied and exquisitely regulated. DNA repair mechanisms are traditionally characterized by the type of damage repaired. A large variety of chemical modifications can alter normal DNA bases and either lead to mutations or block transcription if not repaired, and three distinct pathways exist to remove base damage. Base excision repair (BER) corrects DNA base alterations that do not distort the overall structure of the DNA helix such as bases damaged by oxidation resulting from normal cellular metabolism. While BER removes single damaged bases, nucleotide excision repair (NER) removes short segments of nucleotides (called oligonucleotides) containing damaged bases. NER responds to any alteration that distorts the DNA helix and is the mechanism responsible for repairing bulky base damage caused by carcinogenic chemicals such as benzo [a]pyrene (found in cigarette smoke and automobile exhaust) as well as covalent linkages between adjacent pyrimidine bases resulting from the ultraviolet

Novel Combinatory Approaches to Repair Visual System after Optic Nerve Damage

Science.gov (United States)

2014-09-01

Novel Combinatory Approaches to Repair Visual System After Optic Nerve Damage 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...biological functions such as metabolism, growth, cell cycle, and survival ( Cardone et al., 1998; Diehl, Cheng, Roussel, & Sherr, 1998; Hers, Vincent...of injured adult sensory neurons. The Journal of Neuroscience, 21, 7161–7170. Cardone , M. H., Roy, N., Stennicke, H. R., Salvesen, G. S., Franke, T. F

Isolating human DNA repair genes using rodent-cell mutants

International Nuclear Information System (INIS)

Thompson, L.H.; Weber, C.A.; Brookman, K.W.; Salazar, E.P.; Stewart, S.A.; Mitchell, D.L.

1987-01-01

The DNA repair systems of rodent and human cells appear to be at least as complex genetically as those in lower eukaryotes and bacteria. The use of mutant lines of rodent cells as a means of identifying human repair genes by functional complementation offers a new approach toward studying the role of repair in mutagenesis and carcinogenesis. In each of six cases examined using hybrid cells, specific human chromosomes have been identified that correct CHO cell mutations affecting repair of damage from uv or ionizing radiations. This finding suggests that both the repair genes and proteins may be virtually interchangeable between rodent and human cells. Using cosmid vectors, human repair genes that map to chromosome 19 have cloned as functional sequences: ERCC2 and XRCC1. ERCC1 was found to have homology with the yeast excision repair gene RAD10. Transformants of repair-deficient cell lines carrying the corresponding human gene show efficient correction of repair capacity by all criteria examined. 39 refs., 1 fig., 1 tab

Success of Meniscal Repair at ACL Reconstruction

Science.gov (United States)

Toman, Charles; Spindler, Kurt P.; Dunn, Warren R.; Amendola, Annunziata; Andrish, Jack T.; Bergfeld, John A.; Flanigan, David; Jones, Morgan; Kaeding, Christopher C.; Marx, Robert G.; Matava, Matthew J.; McCarty, Eric C.; Parker, Richard D.; Wolcott, Michelle; Vidal, Armando; Wolf, Brian R.; Huston, Laura J.; Harrell, Frank E.; Wright, Rick W.

2013-01-01

Background Meniscal repair is performed in an attempt to prevent posttraumatic arthritis resulting from meniscal dysfunction after meniscal tears. The socioeconomic implications of premature arthritis are significant in the young patient population. Investigations and techniques focusing on meniscus preservation and healing are now at the forefront of orthopaedic sports medicine. Hypothesis Concomitant meniscal repair with ACL reconstruction is a durable and successful procedure at two year follow-up. Study Design Case Series; Level of evidence, 4. Methods All unilateral primary ACL reconstructions entered in 2002 in a prospective cohort who had meniscal repair at the time of ACLR were evaluated. Validated patient oriented outcome instruments were completed preoperatively and then again at the two-year postoperative time point. Reoperation after the index procedure was also documented and confirmed by operative reports. Results 437 unilateral primary ACL reconstructions were performed with 86 concomitant meniscal repairs (57 medial, 29 lateral) in 84 patients during the study period. Patient follow-up was obtained on 94% (81/86) of the meniscal repairs, allowing confirmation of meniscal repair success (defined as no repeat arthroscopic procedure) or failure. The overall success rate for meniscal repairs was 96% (76/79 patients) at two-year follow-up. Conclusions Meniscal repair is a successful procedure in conjunction with ACL reconstruction. When confronted with a “repairable” meniscal tear at the time of ACL reconstruction, orthopaedic surgeons can expect an estimated >90% clinical success rate at two-year follow-up using a variety of methods as shown in our study. PMID:19465734

Repair of furocoumarin adducts in mammalian cells

International Nuclear Information System (INIS)

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

1984-01-01

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

41 CFR 101-26.301-2 - Issue of used, repaired, and rehabilitated items in serviceable condition.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Issue of used, repaired... and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 26-PROCUREMENT SOURCES AND PROGRAM 26.3-Procurement of GSA Stock Items...

Fragile DNA Repair Mechanism Reduces Ageing in Multicellular Model

DEFF Research Database (Denmark)

Bendtsen, Kristian Moss; Juul, Jeppe Søgaard; Trusina, Ala

2012-01-01

increases the amount of unrepaired DNA damage. Despite this vicious circle, we ask, can cells maintain a high DNA repair capacity for some time or is repair capacity bound to continuously decline with age? We here present a simple mathematical model for ageing in multicellular systems where cells subjected...... to DNA damage can undergo full repair, go apoptotic, or accumulate mutations thus reducing DNA repair capacity. Our model predicts that at the tissue level repair rate does not continuously decline with age, but instead has a characteristic extended period of high and non-declining DNA repair capacity......DNA damages, as well as mutations, increase with age. It is believed that these result from increased genotoxic stress and decreased capacity for DNA repair. The two causes are not independent, DNA damage can, for example, through mutations, compromise the capacity for DNA repair, which in turn...

Arthroscopic undersurface rotator cuff repair versus conventional arthroscopic double-row rotator cuff repair - Comparable results at 2-year follow-up.

Science.gov (United States)

Ang, Benjamin Fu Hong; Chen, Jerry Yongqiang; Yeo, William; Lie, Denny Tijauw Tjoen; Chang, Paul Chee Cheng

2018-01-01

The aim of our study is to compare the improvement in clinical outcomes after conventional arthroscopic double-row rotator cuff repair and arthroscopic undersurface rotator cuff repair. A consecutive series of 120 patients who underwent arthroscopic rotator cuff repair was analysed. Sixty-one patients underwent conventional double-row rotator cuff repair and 59 patients underwent undersurface rotator cuff repair. Several clinical outcomes, including numerical pain rating scale (NPRS), constant shoulder score (CSS), Oxford shoulder score (OSS) and University of California Los Angeles shoulder score (UCLASS), were prospectively recorded by a trained healthcare professional preoperatively and at 3, 6, 12 and 24 months after surgery. Comparing both groups, there were no differences in age, gender and preoperative NPRS, CSS, OSS and UCLASS. However, the tear size was 0.7 ± 0.2 (95% confidence interval (CI) 0.3-1.1) cm larger in the conventional group ( p = 0.002). There was no difference in the improvement of NPRS, CSS, OSS and UCLASS at all time points of follow-up, that is, at 3, 6, 12 and 24 months after surgery. The duration of operation was shorter by 35 ± 3 (95% CI 28-42) min in the undersurface group ( p rotator cuff repair and conventional arthroscopic double-row rotator cuff repair showed marked improvements in clinical scores when compared preoperatively, and there was no difference in improvements between both groups. Arthroscopic undersurface rotator cuff repair is a faster technique compared to the conventional arthroscopic double-row rotator cuff repair.

Improving Aviation Depot Level Repairable (AVDLR) Inventory and Repair Management

National Research Council Canada - National Science Library

Baird, Dennis

1997-01-01

.... Additionally, research was conducted to document the management process for determining repair requirements at the Naval Inventory Control Point Philadelphia and how those requirements are accepted...

Induced repair and mutagenesis in animal cells

International Nuclear Information System (INIS)

Takimoto, Koichi

1981-01-01

Induced repair and mutagenesis of animal cells against UV were studied in contrast with SOS repair of E. coli primarily by the use of viruses. Since UV-enhanced reactivation is a phenomenon similar to UV-reactivation (mutagenesis) and the presence of lesion bypass synthsis has been suggested, UV-enhanced reactivation has several common aspects with SOS reactivation of E. coli. However, correlation is not necessarily noted between increase in the viral survival rate and mutagenesis, nor do protease blockers exert any effect. Therefore, SOS repair of E. coli may have different mechansms from induced repair and mutagenesis in animal cells. (Ueda, J.)

Failure Modes in Concrete Repair Systems due to Ongoing Corrosion

Directory of Open Access Journals (Sweden)

Mladena Luković

2017-01-01

Full Text Available Corrosion of steel reinforcement is the main cause of deterioration in reinforced concrete structures. It can result in cracking and spalling of the concrete cover. After the damaged cover is repaired, reinforcement corrosion might continue and even accelerate. While the development of the corrosion cell is difficult to control, the damage can be possibly delayed and controlled by use of a suitable repair material. The lattice fracture model is used in this paper to investigate the performance of strain hardening cementitious composite (SHCC in concrete repair systems exposed to ongoing corrosion. Numerical results were verified by experimental tests when SHCC, nonreinforced material (repair mortar, and commercial repair mortar are used as repair materials. In experiments, reinforcement bars (surrounded by a repair material were exposed to accelerated corrosion tests. The influence of the substrate surface preparation, the type of repair material, the interface, and the substrate strength on the resulting damage and failure mode of repair systems are discussed. In general, SHCC repair enables distributed cracking with small crack widths, up to several times smaller compared to repair mortar. Furthermore, more warning signs prior to the final failure are present in the SHCC repair system.

Saturation of DNA repair in mammalian cells

Energy Technology Data Exchange (ETDEWEB)

Ahmed, F E; Setlow, R B

1979-01-01

Excision repair seems to reach a plateau in normal human cells at a 254 nm dose near 20 J/m/sup 2/. We measured excision repair in normal human fibroblasts up to 80 J/m/sup 2/. The four techniques used (unscheduled DNA synthesis, photolysis of BrdUrd incorporated during repair, loss of sites sensitive to a UV endonuclease from Micrococcus luteus, and loss of pyrimidine dimers from DNA) showed little difference between the two doses. Moreover, the loss of endonuclease sites in 24h following two 20 J/m/sup 2/ doses separated by 24h was similar to the loss observed following one dose. Hence, we concluded that the observed plateau in excision repair is real and does not represent some inhibitory process at high doses but a true saturation of one of the rate limiting steps in repair.

Exciting News From Va. Tech - Repaired Pallets May Be Stronger Than the Original

Science.gov (United States)

John W. Clarke; Marshall S. White; T.E. McLain; Philip A. Araman

1995-01-01

Virginia Tech, in cooperation with the NWPCA and the Southern Research Station of the USDA Forest Service, conducted a research program on the use of metal plates for repair of stringer pallets. This study looked at common stringer failure locations: splits between the notches, splits above the notches, and splits in the end feet. One of the research objectives was to...

Initial experience of laparoscopic incisional hernia repair.

Science.gov (United States)

Razman, J; Shaharin, S; Lukman, M R; Sukumar, N; Jasmi, A Y

2006-06-01

Laparoscopic repair of ventral and incisional hernia has become increasingly popular as compared to open repair. The procedure has the advantages of minimal access surgery, reduction of post operative pain and the recurrence rate. A prospective study of laparoscopic incisional hernia repair was performed in our center from August 2002 to April 2004. Eighteen cases (n: 18) were performed during the study period. Fifteen cases (n: 15) had open hernia repair previously. Sixteen patients (n: 16) had successful repair of the hernia with the laparoscopic approach and two cases were converted to open repair. The mean hernia defect size was 156cm2. There was no intraoperative or immediate postoperative complication. The mean operating time was 100 +/- 34 minutes (75 - 180 minutes). The postoperative pain was graded as mild to moderate according to visual analogue score. The mean day of discharge after surgery was two days (1 - 3 days). During follow up, three patients (16.7%) developed seroma at the hernia sac which was resolved with conservative management after three weeks. One (5.6%) patient developed recurrence six months after surgery. In conclusion, laparoscopic repair of incisional hernia particularly recurrent hernia has been shown to be safe and effective in our centre. However, careful patient selection and acquiring the necessary advanced laparoscopic surgical skills coupled with the proper use of equipment are mandatory before embarking on this procedure.

Cloning human DNA repair genes

International Nuclear Information System (INIS)

Jeggo, P.A.; Carr, A.M.; Lehmann, A.R.

1994-01-01

Many human genes involved in the repair of UV damage have been cloned using different procedures and they have been of great value in assisting the understanding of the mechanism of nucleotide excision-repair. Genes involved in repair of ionizing radiation damage have proved more difficult to isolate. Positional cloning has localized the XRCC5 gene to a small region of chromosome 2q33-35, and a series of yeast artificial chromosomes covering this region have been isolated. Very recent work has shown that the XRCC5 gene encodes the 80 kDa subunit of the Ku DNA-binding protein. The Ku80 gene also maps to this region. Studies with fission yeast have shown that radiation sensitivity can result not only from defective DNA repair but also from abnormal cell cycle control following DNA damage. Several genes involved in this 'check-point' control in fission yeast have been isolated and characterized in detail. It is likely that a similar checkpoint control mechanism exists in human cells. (author)

Metabolite damage and repair in metabolic engineering design

Energy Technology Data Exchange (ETDEWEB)

Sun, Jiayi; Jeffryes, James G.; Henry, Christopher S.; Bruner, Steven D.; Hanson, Andrew D.

2017-11-01

The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields, and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects.

Mitral valve repair: an echocardiographic review: Part 2.

Science.gov (United States)

Maslow, Andrew

2015-04-01

Echocardiographic imaging of the mitral valve before and immediately after repair is crucial to the immediate and long-term outcome. Prior to mitral valve repair, echocardiographic imaging helps determine the feasibility and method of repair. After the repair, echocardiographic imaging displays the new baseline anatomy, assesses function, and determines whether or not further management is necessary. Three-dimensional imaging has improved the assessment of the mitral valve and facilitates communication with the surgeon by providing the surgeon with an image that he/she might see upon opening up the atrium. Further advancements in imaging will continue to improve the understanding of the function and dysfunction of the mitral valve both before and after repair. This information will improve treatment options, timing of invasive therapies, and advancements of repair techniques to yield better short- and long-term patient outcomes. The purpose of this review was to connect the echocardiographic evaluation with the surgical procedure. Bridging the pre- and post-CPB imaging with the surgical procedure allows a greater understanding of mitral valve repair.

OPTIMUM DISTRIBUTION OF REPAIRS IN ТS-8 OF ELECTRIC LOCOMOTIVES VL80С BETWEEN REPAIR DEPOTS IN THE REPUBLIC OF KAZAKHSTAN

Directory of Open Access Journals (Sweden)

Seidulla ABDULLAYEV

2017-06-01

Full Text Available The article presents the solution for the problem of optimal distribution of electric locomotives in repair enterprises for carrying out repairs in the frame of technical service - 8 (ТS-8 and increased technical service - 8 (ITS-8. The aim of the study is to improve the efficacy of a rolling stock with a simultaneous decrease in the total expenses connected with the repair of locomotives and their transportation in repair enterprises. This is possible due to a reduction in the requirement for repairs by optimization of a resource before change of wheel bandages in electric locomotives VL80С that promotes an increase in their between-repairs run.

Epigenetic changes of DNA repair genes in cancer.

Science.gov (United States)

Lahtz, Christoph; Pfeifer, Gerd P

2011-02-01

'Every Hour Hurts, The Last One Kills'. That is an old saying about getting old. Every day, thousands of DNA damaging events take place in each cell of our body, but efficient DNA repair systems have evolved to prevent that. However, our DNA repair system and that of most other organisms are not as perfect as that of Deinococcus radiodurans, for example, which is able to repair massive amounts of DNA damage at one time. In many instances, accumulation of DNA damage has been linked to cancer, and genetic deficiencies in specific DNA repair genes are associated with tumor-prone phenotypes. In addition to mutations, which can be either inherited or somatically acquired, epigenetic silencing of DNA repair genes may promote tumorigenesis. This review will summarize current knowledge of the epigenetic inactivation of different DNA repair components in human cancer.

Improved Aviation Readiness and Inventory Reductions Through Repair Cycle Time Reductions Using Modeling and Simulation.

Science.gov (United States)

1997-12-01

three NADEP’s within the continental United States and fleet repair sites in Italy and Japan. These facilities are located to support specific...number order. This same morning, P&E’s have a last opportunity to edit the induction file through the Planner and Estimator Cancellation Program ( PECAN

Performance of patch repaired composite panels under fatigue loads

International Nuclear Information System (INIS)

Darwish, Feras H.; Hamoush, S.; Shivakumar, K.

2006-01-01

This paper evaluates the performance of bonded patch-scarf repairs of full scale laminated composite panels under cyclic load conditions. Nondestructive testing to characterize the quality of repairs and destructive testing to evaluate the performance of repaired panels were used in this study. Carbon/Epoxy prepreg material used was used to lay up six-ply (12 in. x 27 in. /305x686mm) (-60/60/0) s quasi-isotropic laminates. 7-ply scarf repair with a gradient of 0.5 inch (12.7mm) per layer was used to perform the repair of a damaged zone. The patch consisted of 7.5 inches (190mm) diameter adhesive film, 1 inch (25.4mm) diameter filler ply at 90fiber orientation, and six plies (2-7 inches (51-178mm) diameter) to match the lay-up of the parent material. The study was extended to include defective repairs. The defect was engineered by inserting a 1 inch (25.4 mm) circular Teflon flaw between the fifth and sixth layers of the patch. A total of 28 panels were prepared and divided into five categories: (1) three pristine panels (undamaged parental materials); (2) three damaged panels (1-inch-centered-hole); (3) two repaired panels with wrong fiber orientation; (4) nine good repaired panels, and (5) eleven defective repair panels (1 inch flaw). A nondestructive evaluation to check the conditions of the repairs was performed on most of the tested panels that include the pulse-echo C-scan and pseudo through transmission air coupled and water coupled C-scan. Based on the results of the experimental evaluation of this study, good repair restored 95% of the tensile strength while defective repair restored 90% of the tensile strength of the pristine panels. Under fatigue loading, panels repaired with a 1 inch delamination flaw within the patch layers showed a major reduction in fatigue life compared to the good repair panels under similar loading conditions. (author)

Numerical simulation of CFRP-repaired reinforced concrete columns.

Science.gov (United States)

2014-07-01

The overarching goal of this study was to investigate the influence of repair to individual reinforced concrete bridge columns on the : post-repair seismic performance of the bridge system. A method was developed to rapidly repair an earthquake-damag...

Investigations of DNA-repair in New Zealand mice

Energy Technology Data Exchange (ETDEWEB)

Tuschl, H; Kovac, R; Altmann, H

1974-09-01

DNA repair was investigated in New Zealand mice strains which developed murine lupus and compared with Swiss control mice. Unscheduled DNA synthesis demonstrated by autoradiography was used to measure the repair capacity of spleen cells. After gamma-irradiation DNA repair was decreased in the autoimmune strains, while it was significantly increased after UV-irradiation. A possible relationship between repair capacity after gamma-respectively UV-irradiation and the etiologic factor of autoimmunity is discussed. (auth)

Nrf2 facilitates repair of radiation induced DNA damage through homologous recombination repair pathway in a ROS independent manner in cancer cells

Energy Technology Data Exchange (ETDEWEB)

Jayakumar, Sundarraj; Pal, Debojyoti; Sandur, Santosh K., E-mail: sskumar@barc.gov.in

2015-09-15

Highlights: • Nrf2 inhibition in A549 cells led to attenuated DNA repair and radiosensitization. • Influence of Nrf2 on DNA repair is not linked to its antioxidant function. • Nrf2 influences DNA repair through homologous recombination (HR) repair pathway. • Many genes involved in HR pathway show ARE sequences in their upstream region. - Abstract: Nrf2 is a redox sensitive transcription factor that is involved in the co-ordinated transcription of genes involved in redox homeostasis. But the role of Nrf2 in DNA repair is not investigated in detail. We have employed A549 and MCF7 cells to study the role of Nrf2 on DNA repair by inhibiting Nrf2 using all-trans retinoic acid (ATRA) or by knock down approach prior to radiation exposure (4 Gy). DNA damage and repair analysis was studied by γH2AX foci formation and comet assay. Results suggested that the inhibition of Nrf2 in A549 or MCF7 cells led to significant slowdown in DNA repair as compared to respective radiation controls. The persistence of residual DNA damage even in the presence of free radical scavenger N-acetyl cysteine, suggested that the influence of Nrf2 on DNA repair was not linked to its antioxidant functions. Further, its influence on non-homologous end joining repair pathway was studied by inhibiting both Nrf2 and DNA-PK together. This led to synergistic reduction of survival fraction, indicating that Nrf2 may not be influencing the NHEJ pathway. To investigate the role of homologous recombination repair (HR) pathway, RAD51 foci formation was monitored. There was a significant reduction in the foci formation in cells treated with ATRA or shRNA against Nrf2 as compared to their respective radiation controls. Further, Nrf2 inhibition led to significant reduction in mRNA levels of RAD51. BLAST analysis was also performed on upstream regions of DNA repair genes to identify antioxidant response element and found that many repair genes that are involved in HR pathway may be regulated by Nrf2

Exteriorization or in-situ repair, comparison of options for uterine repair at cesarean delivery

International Nuclear Information System (INIS)

Zafar, B.; Shehzad, F.; Safdar, C.A.

2016-01-01

Objective of study is to compare peri-operative complications between exteriorization and intraabdominal repair of uterus after cesarean delivery. Study Design: Randomized controlled trial. Place and Duration of Study: Obstetrics and Gynecology Department of Pakistan Ordinance Factory Hospital, Wah Cantt, from 1st April 2010 to 30th September 2010. Material and Methods: Patients planned for 1st cesarean section under spinal anesthesia were randomly allocated by lottery method to exteriorized (A) or in situ uterine repair (B) group. Patients with history of uterine surgeries and cesarean section were excluded from study. Variables analyzed were operation time, peri-operative hemoglobin (Hb) fall, nausea and vomiting during the cesarean delivery. Results: The study analyzed 170 patients and divided them in 2 groups, having no significant difference with respect to maternal demographics, procedure statistics and indication of cesarean section. Significant difference was observed in operation time being 32.78 min in exteriorized group and 36.38 min in situ uterine repair group (p-value 0.0001). Hb percent fall was 0.85 g/dl and 0.92 g/dl respectively in both groups (p-value 0.62) Nausea and vomiting was 23.5 percent in group A and 11.8 percent in group B (p-value 0.02, 0.04 respectively) Conclusion: Peri-operative complications like operative time and Hb fall are less in uterine repair after temporary exteriorization as compared to intra-abdominal repair of uterus after cesarean delivery. Nausea and vomiting were increased in exteriorized group but proper regional anesthetic technique and achieving adequate analgesia can reduce patient discomfort. (author)

Clamp wins pipe repair prize

Energy Technology Data Exchange (ETDEWEB)

Anon.

2001-04-01

This paper describes the permanent pipeline repair system, developed by Tekmar, which is powered by seawater hydraulics and is easily installed and tested by any workclass remotely operated vehicle (rov). Details are given of the two main components of the system, namely, the diverless high pressure split repair clamp and the rov-operated tool to install it.

Nucleotide excision repair II: From yeast to mammals

NARCIS (Netherlands)

J.H.J. Hoeijmakers (Jan)

1993-01-01

textabstractAn intricate network of repair systems safeguards the integrity of genetic material, by eliminating DNA lesions induced by numerous environmental and endogenous genotoxic agents. Nucleotide excision repair (NER) is one of the most versatile DNA repair systems. Deficiencies in this

Repair welding of cracked steam turbine blades

International Nuclear Information System (INIS)

Bhaduri, A.K.; Gill, T.P.S.; Albert, S.K.; Shanmugam, K.; Iyer, D.R.

1999-01-01

The procedure for repair welding of cracked steam turbine blades made of martensitic stainless steels has been developed using the gas tungsten arc welding process. Weld repair procedures were developed using both ER316L austenitic stainless steel filler wire and ER410 martensitic stainless steel filler wire. The repair welding procedure with austenitic filler wire was developed to avoid preheating of the blade as also hydrogen induced cold cracking, and involved evaluation of three different austenitic filler wires, viz. ER309L, ER316L and ERNiCr-3. The overall development of the repair welding procedure included selection of welding consumables (for austenitic filler metal), optimisation of post weld heat treatment parameters, selection of suitable method for local pre-heating and post-weld heat treatment (PWHT) of the blades, determination of mechanical properties of weldments in as-welded and PWHT conditions, and microstructural examination. After various trials using different procedures, the procedure of local PWHT using electrical resistance heating on the top surface of the weldment and monitoring the temperature by placing a thermocouple at the bottom of the weld, was found to give the most satisfactory results. A similar procedure was used for preheating while using ER410 filler metal. Mechanical testing of weldments before and after PWHT involved tensile tests at room temperature, face and root bend tests, and microhardness measurements across the fusion line and heat affected zone. During procedure qualification, mock-ups and actual repair welding, dye penetrant testing was used at different stages and where ever possible radiography was carried out. These procedures were developed for repair welding of cracked blades in the low-pressure (LP) steam turbines of Indian nuclear power plants. The procedure with ER316 L filler wire has so far been applied for repair welding of 2 cracked blades (made of AISI 410 SS) of LP steam turbines, while the procedure

DNA Damage Induced by Alkylating Agents and Repair Pathways

OpenAIRE

Natsuko Kondo; Akihisa Takahashi; Koji Ono; Takeo Ohnishi

2010-01-01

The cytotoxic effects of alkylating agents are strongly attenuated by cellular DNA repair processes, necessitating a clear understanding of the repair mechanisms. Simple methylating agents form adducts at N- and O-atoms. N-methylations are removed by base excision repair, AlkB homologues, or nucleotide excision repair (NER). O 6-methylguanine (MeG), which can eventually become cytotoxic and mutagenic, is repaired by O 6-methylguanine-DNA methyltransferase, and O 6MeG:T mispairs are recognized...

Repair and cell cycle response in cells exposed to environmental biohazards. Progress report, 1 June 1982-31 May 1983

International Nuclear Information System (INIS)

Billen, D.; Hadden, C.T.

1983-01-01

The research program has attempted to determine low environmental agents, especially ionizing radiation, interact with DNA and how the cells respond to the resulting damage. The focus has been on the spectrum of damage generated in DNA, the kinds of damage that can be repaired, and the mechanisms of repair. The effects of radioprotective agents and certain sensitizing conditions on breakage of DNA in bacterial cells by ionizing radiation, and mechanisms of enzymatic excision of pyrimidine dimers and other DNA adducts have been studied

Chitosan adhesive for laser tissue repair

Science.gov (United States)

Lauto, A.; Stoodley, M.; Avolio, A.; Foster, L. J. R.

2006-02-01

Background. Laser tissue repair usually relies on haemoderivate solders, based on serum albumin. These solders have intrinsic limitations that impair their widespread use, such as limited repair strength, high solubility, brittleness and viral transmission. Furthermore, the solder activation temperature (65-70 °C) can induce significant damage to tissue. In this study, a new laser-activated biomaterial for tissue repair was developed and tested in vitro and in vivo to overcome some of the shortcomings of traditional solders. Materials and Methods. Flexible and insoluble strips of chitosan adhesive (surface area ~34 mm2, thickness ~20 μm) were developed and bonded on sheep intestine with a laser fluence and irradiance of 52 +/- 2 J/cm2 and ~15 W/cm2 respectively. The temperature between tissue and adhesive was measured using small thermocouples. The strength of repaired tissue was tested by a calibrated tensiometer. The adhesive was also bonded in vivo to the sciatic nerve of rats to assess the thermal damage induced by the laser (fluence = 65 +/- 11 J/cm2, irradiance = 15 W/cm2) four days post-operatively. Results. Chitosan adhesives successfully repaired intestine tissue, achieving a repair strength of 0.50 +/- 0.15 N (shear stress = 14.7 +/- 4.7 KPa, n=30) at a temperature of 60-65 °C. The laser caused demyelination of axons at the operated site; nevertheless, the myelinated axons retained their normal morphology proximally and distally.

Artificial-Crack-Behavior Test Evaluation of the Water-Leakage Repair Materials Used for the Repair of Water-Leakage Cracks in Concrete Structures

Directory of Open Access Journals (Sweden)

Soo-Yeon Kim

2016-09-01

Full Text Available There are no existing standard test methods at home and abroad that can verify the performance of water leakage repair materials, and it is thus very difficult to perform quality control checks in the field of water leakage repair. This study determined that the key factors that have the greatest impact on the water leakage repair materials are the micro-behaviors of cracks, and proposed an artificial-crack-behavior test method for the performance verification of the repair materials. The performance of the 15 kinds of repair materials that are currently being used in the field of water leakage repair was evaluated by applying the proposed test method. The main aim of such a test method is to determine if there is water leakage by injecting water leakage repair materials into a crack behavior test specimen with an artificial 5-mm crack width, applying a 2.5 mm vertical behavior load at 100 cycles, and applying 0.3 N/mm2 constant water pressure. The test results showed that of the 15 kinds of repair materials, only two effectively sealed the crack and thus stopped the water leakage. The findings of this study confirmed the effectiveness of the proposed artificial-crack-behavior test method and suggest that it can be used as a performance verification method for checking the responsiveness of the repair materials being used in the field of water leakage repair to the repetitive water leakage behaviors that occur in concrete structures. The study findings further suggest that the use of the proposed test method makes it possible to quantify the water leakage repair quality control in the field.

Inhibition of DNA repair by trifluoperazine

Energy Technology Data Exchange (ETDEWEB)

Charp, P.A.; Regan, J.D.

1985-01-01

The authors examined the possible role of calmodulin in the excision repair of ultraviolet light-induced pyrimidine dimers in damaged DNA by means of specialized assay systems. These assays included bromodeoxyuridine photolysis, dimer chromatography and cytosine arabinoside incorporation in conjunction with hydroxyurea. The calmodulin antagonist, trifluoperazine, and the calcium-chelating agent, EGTA, were employed to ascertain what affect calmodulin played in the repair process. Normal human fibroblast cells are used in all studies described in this report. After exposure to 10 J/m2 of 254 nm light, the authors observed a decrease of about 30% in the number of single-strand breaks produced in the presence of 25 M trifluoperazine (1.9 vs. 3.3) in controls although the numbers of bases re-inserted in the repaired regions were similar (64 vs. 72). Measurement of thymine-containing dimers remaining throughout a 24 h time period indicated a 30% difference decrease in the number of cytosine arabinoside arrested repair sites in the presence of either EGTA or trifluoperazine. The results are discussed with relation to the possibility of calmodulin altering the initial incision by repair endonuclease. 27 references, 3 figures.

The Usefulness of International Cooperation in the Repair of Inguinal Hernias in Sub-Saharan Africa.

Science.gov (United States)

Gil, José; Rodriguez, J M; Gil, E; Hernández Agúera, Q; González, F M; García, J A; Balsalobre, M D; Tortosa, J A; Hernández Palazón, D; Diallo, A B; Parrilla, P

2015-11-01

The burden of disease and mortality associated with inguinal hernia in Africa, especially in sub-Saharan Africa, is very high. The purpose of this study is to show that International Cooperation work in the field of hernia repair is effective; it minimizes the delay in hernia repairs in the targeted population, and can prevent a large number of disability-adjusted life years (DALYs). As a part of an International Cooperation program, a total of 990 black patients with inguinal hernias were studied, in whom hernioplasty was performed using polypropylene mesh. The type of hernia and surgical technique were studied. Indicators of scientific and technical quality, indicators of efficiency and of effectiveness were analyzed. The results on the usefulness of interventions were calculated as avoided DALYs. Surgery was performed on 926 patients with a total of 1033 hernia repairs. 87.2 % of the repairs were made with mesh. There was no mortality in the series, complications were minor, and 85.7 % of patients remained less than 24 h in the center. There was a 2.8 % of recurrence, with a follow-up 58.7 % of the patients in the first year. 5014 DALYs were avoided, and the average of the avoided DALYs per patient was of 5.41. Hernia repair with mesh in low development countries is a procedure with low morbidity and high effectiveness that can prevent a large number of DALYs.

Nuclear translocation contributes to regulation of DNA excision repair activities

DEFF Research Database (Denmark)

Knudsen, Nina Østergaard; Andersen, Sofie Dabros; Lützen, Anne

2009-01-01

for regulation of nuclear import that is necessary for proper localization of the repair proteins. This review summarizes the current knowledge on nuclear import mechanisms of DNA excision repair proteins and provides a model that categorizes the import by different mechanisms, including classical nuclear import......DNA mutations are circumvented by dedicated specialized excision repair systems, such as the base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR) pathways. Although the individual repair pathways have distinct roles in suppressing changes in the nuclear DNA......, it is evident that proteins from the different DNA repair pathways interact [Y. Wang, D. Cortez, P. Yazdi, N. Neff, S.J. Elledge, J. Qin, BASC, a super complex of BRCA1-associated proteins involved in the recognition and repair of aberrant DNA structures, Genes Dev. 14 (2000) 927-939; M. Christmann, M...

Imperfect repair and lifesaving in heterogeneous populations

Energy Technology Data Exchange (ETDEWEB)

Finkelstein, Maxim [Department of Mathematical Statistics, University of the Free State, PO Box 339, 9300 Bloemfontein (South Africa) and Max Planck Institute for Demographic Research, Rostock (Germany)]. E-mail: FinkelM.SCl@mail.uovs.ac.za

2007-12-15

In this theoretical paper we generalize the notion of minimal repair to the heterogeneous case, when the lifetime distribution function can be modeled by continuous or a discrete mixture of distributions. The statistical (black box) minimal repair and the minimal repair based on information just before the failure of an object are considered. The corresponding failure (intensity) rate processes are defined and analyzed. Demographic lifesaving model is also considered: each life is saved (cured) with some probability (or equivalently a proportion of individuals who would have died are now resuscitated and given another chance). Those who are saved experience the statistical minimal repair. Both of these models are based on the Poisson or non-homogeneous Poisson processes of underlying events, which allow for considering heterogeneity. We also consider the new model of imperfect repair in the homogeneous case and present generalizations to the heterogeneous setting.

DNA replication and repair in Tilapia cells

International Nuclear Information System (INIS)

Yew, F.H.; Chang, L.M.

1984-01-01

The effect of ultraviolet radiation on a cell line established from the warm water fish Tilapia has been assessed by measuring the rate of DNA synthesis, excision repair, post-replication repair and cell survival. The cells tolerate ultraviolet radiation better than mammalian cells with respect to DNA synthesis, post-replication repair and cell survival. They are also efficient in excision repair, which in other fish cell lines has been found to be at a low level or absent. Their response to the inhibitors hydroxyurea and 1-β-D-arabinofuranosylcytosine is less sensitive than that of other cell lines, yet the cells seem to have very small pools of DNA precursor. (author)

Re-initiation repair in bacteriophage T4

International Nuclear Information System (INIS)

Cupido, M.

1981-01-01

Irradiation of bacteriophage T4 with ultraviolet light induces the formation of pyrimidine dimers in its DNA. These dimers hamper replication of DNA and, to a lesser extent, transcription of DNA after its infection of bacteria. A number of pathways enable phage T4 to multiply dimer-containing DNA. One of these pathways has been named replication repair and is described in this thesis. The properties of two phage strains, unable to perform replication repair, have been studied to obtain a picture of the repair process. The mutations in these strains that affect replication repair have been located on the genomic map of T4. (Auth.)

A structured, extended training program to facilitate adoption of new techniques for practicing surgeons.

Science.gov (United States)

Greenberg, Jacob A; Jolles, Sally; Sullivan, Sarah; Quamme, Sudha Pavuluri; Funk, Luke M; Lidor, Anne O; Greenberg, Caprice; Pugh, Carla M

2018-01-01

Laparoscopic inguinal hernia repair has been shown to have significant benefits when compared to open inguinal hernia repair, yet remains underutilized in the United States. The traditional model of short, hands-on, cognitive courses to enhance the adoption of new techniques fails to lead to significant levels of practice implementation for most surgeons. We hypothesized that a comprehensive program would facilitate the adoption of laparoscopic inguinal hernia repair (TEP) for practicing surgeons. A team of experts in simulation, coaching, and hernia care created a comprehensive training program to facilitate the adoption of TEP. Three surgeons who routinely performed open inguinal hernia repair with greater than 50 cases annually were recruited to participate in the program. Coaches were selected based on their procedural expertise and underwent formal training in surgical coaching. Participants were required to evaluate all aspects of the educational program and were surveyed out to one year following completion of the program to assess for sustained adoption of TEP. All three participants successfully completed the first three steps of the seven-step program. Two participants completed the full course, while the third dropped out of the program due to time constraints and low case volume. Participant surgeons rated Orientation (4.7/5), GlovesOn training (5/5), and Preceptored Cases (5/5) as highly important training activities that contributed to advancing their knowledge and technical performance of the TEP procedure. At one year, both participants were performing TEPs for "most of their cases" and were confident in their ability to perform the procedure. The total cost of the program including all travel, personal coaching, and simulation was $8638.60 per participant. Our comprehensive educational program led to full and sustained adoption of TEP for those who completed the course. Time constraints, travel costs, and case volume are major considerations for

Reasoning about repairability of workflows at design time

NARCIS (Netherlands)

Tagni, Gaston; Ten Teije, Annette; Van Harmelen, Frank

2009-01-01

This paper describes an approach for reasoning about the repairability of workflows at design time. We propose a heuristic-based analysis of a workflow that aims at evaluating its definition, considering different design aspects and characteristics that affect its repairability (called repairability

Autogenous Metallic Pipe Leak Repair in Potable Water Systems.

Science.gov (United States)

Tang, Min; Triantafyllidou, Simoni; Edwards, Marc A

2015-07-21

Copper and iron pipes have a remarkable capability for autogenous repair (self-repair) of leaks in potable water systems. Field studies revealed exemplars that metallic pipe leaks caused by nails, rocks, and erosion corrosion autogenously repaired, as confirmed in the laboratory experiments. This work demonstrated that 100% (N = 26) of 150 μm leaks contacting representative bulk potable water in copper pipes sealed autogenously via formation of corrosion precipitates at 20-40 psi, pH 3.0-11.0, and with upward and downward leak orientations. Similar leaks in carbon steel pipes at 20 psi self-repaired at pH 5.5 and 8.5, but two leaks did not self-repair permanently at pH 11.0 suggesting that water chemistry may control the durability of materials that seal the leaks and therefore the permanence of repair. Larger 400 μm holes in copper pipes had much lower (0-33%) success of self-repair at pH 3.0-11.0, whereas all 400 μm holes in carbon steel pipes at 20 psi self-repaired at pH 4.0-11.0. Pressure tests indicated that some of the repairs created at 20-40 psi ambient pressure could withstand more than 100 psi without failure. Autogenous repair has implications for understanding patterns of pipe failures, extending the lifetime of decaying infrastructure, and developing new plumbing materials.

Composite repairs qualification according to ISO/TS 24817

Energy Technology Data Exchange (ETDEWEB)

Meniconi, Luiz C.M.; Perrut, Valber A. [Petroleo Brasileiro S.A. (PETROBRAS/CENPES), Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

2009-07-01

Composite repairs for metallic pipes from three different suppliers were evaluated according to ISO Technical Specification TS 24817. The intended application scenarios are offshore production plants, but the design methodology is also applicable to onshore pipelines and pipework. The evaluation covered all the relevant mechanical properties and established the maximum application temperatures for each repair system. The tests also considered the application of composite repair sleeves to metallic pipes with through thickness defects, by measuring the strain energy release rates of the composite-metal interfaces. The test campaigns aimed to verify the applicability of the recently published ISO document, and to implement it as the routine procedure for composite repairs evaluation within PETROBRAS. The tests also addressed the influence of metallic pipe surface preparation on the final properties of the repair sleeves, especially in relation to the long term behavior of leaking pipes repaired by means of composite materials. (author)

Flexible Plug Repair for Shuttle Wing Leading Edge

Science.gov (United States)

Camarda, Charles J.; Sikora, Joseph; Smith, Russel; Rivers, H.; Scotti, Stephen J.; Fuller, Alan M.; Klacka, Robert; Reinders, Martin; Schwind, Francis; Sullivan, Brian;

46 CFR 35.25-5 - Repairs of boilers and unfired pressure vessels and reports of repairs or accidents by chief...

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Repairs of boilers and unfired pressure vessels and..., DEPARTMENT OF HOMELAND SECURITY TANK VESSELS OPERATIONS Engine Department § 35.25-5 Repairs of boilers and... any repairs to boilers or unfired pressure vessels, the chief engineer shall submit a report covering...

Additive Manufacturing in Offsite Repair of Consumer Electronics

Science.gov (United States)

Chekurov, Sergei; Salmi, Mika

Spare parts for products that are at the end of their life cycles, but still under warranty, are logistically difficult because they are commonly not stored in the central warehouse. These uncommon spare parts occupy valuable space in smaller inventories and take a long time to be transported to the point of need, thus delaying the repair process. This paper proposes that storing the spare parts on a server and producing them with additive manufacturing (AM) on demand can shorten the repair cycle by simplifying the logistics. Introducing AM in the repair supply chain lowers the number of products that need to be reimbursed to the customer due to lengthy repairs, improves the repair statistics of the repair shops, and reduces the number of items that are held in stock. For this paper, the functionality of the concept was verified by reverse engineering a memory cover of a portable computer and laser sintering it from polyamide 12. The additively manufactured component fit well and the computer operated normally after the replacement. The current spare part supply chain model and models with AM machinery located at the repair shop, the centralized spare part provider, and the original equipment manufacturer were provided. The durations of the repair process in the models were compared by simulating two scenarios with the Monte Carlo method. As the biggest improvement, the model with the AM machine in the repair shop reduced the duration of the repair process from 14 days to three days. The result points to the conclusion that placing the machine as close to the need as possible is the best option, if there is enough demand. The spare parts currently compatible with AM are plastic components without strict surface roughness requirements, but more spare parts will become compatible with the development of AM.

Subsequent Shoulder Surgery After Isolated Arthroscopic SLAP Repair.

Science.gov (United States)

Mollon, Brent; Mahure, Siddharth A; Ensor, Kelsey L; Zuckerman, Joseph D; Kwon, Young W; Rokito, Andrew S

2016-10-01

To quantify the incidence of and identify the risk factors for subsequent shoulder procedures after isolated SLAP repair. New York's Statewide Planning and Research Cooperative System database was searched between 2003 and 2014 to identify individuals with the sole diagnosis of a SLAP lesion who underwent isolated arthroscopic SLAP repair. Patients were longitudinally followed up for a minimum of 3 years to analyze for subsequent ipsilateral shoulder procedures. Between 2003 and 2014, 2,524 patients met our inclusion criteria. After 3 to 11 years of follow-up, 10.1% of patients (254 of 2,524) underwent repeat surgical intervention on the same shoulder as the initial SLAP repair. The mean time to repeat shoulder surgery was 2.3 ± 2.1 years. Subsequent procedures included subacromial decompression (35%), debridement (26.7%). repeat SLAP repair (19.7%), and biceps tenodesis or tenotomy (13.0%). After isolated SLAP repair, patients aged 20 years or younger were more likely to undergo arthroscopic Bankart repair (odds ratio [OR], 2.91; 95% confidence interval [CI], 1.36-6.21; P = .005), whereas age older than 30 years was an independent risk factor for subsequent acromioplasty (OR, 2.3; 95% CI, 1.4-3.7; P surgery after isolated SLAP repair, often related to an additional diagnosis, suggesting that clinicians should consider other potential causes of shoulder pain when considering surgery for patients with SLAP lesions. In addition, the number of isolated SLAP repairs performed has decreased over time, and management of failed SLAP repair has shifted toward biceps tenodesis or tenotomy over revision SLAP repair in more recent years. Level III, case-control study. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Underwater coating repair cuts nuclear maintenance costs

International Nuclear Information System (INIS)

Stuart, C.O.

1993-01-01

This article discusses the cleaning and recoating/repair of condensate tanks or other vessels in a nuclear power plant. The topics of the article include the safety and regulatory need for this system of repair, a description of the work done on the Brown's Ferry MK-1 suppression chamber, coating failure mechanisms, qualitative inspection, quantitative inspection, quantitative inspection results, spot repairs, and economic considerations

49 CFR 192.719 - Transmission lines: Testing of repairs.

Science.gov (United States)

2010-10-01

... pipe before it is installed. (b) Testing of repairs made by welding. Each repair made by welding in... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Testing of repairs. 192.719... Transmission lines: Testing of repairs. (a) Testing of replacement pipe. If a segment of transmission line is...

FLEXOR TENDON REPAIR IN THE HAND

African Journals Online (AJOL)

Method of Repair. Cases. AGE, SEX ... method is at fault and not the dexterity of the operator or his technique. .... Physio- therapy seldom makes stiff fingers work, but it prevents .... or repaired later by direct suture, graft or transplant. No. of.

A novel conduit-based coaptation device for primary nerve repair.

Science.gov (United States)

Bamba, Ravinder; Riley, D Colton; Kelm, Nathaniel D; Cardwell, Nancy; Pollins, Alonda C; Afshari, Ashkan; Nguyen, Lyly; Dortch, Richard D; Thayer, Wesley P

2018-06-01

Conduit-based nerve repairs are commonly used for small nerve gaps, whereas primary repair may be performed if there is no tension on nerve endings. We hypothesize that a conduit-based nerve coaptation device will improve nerve repair outcomes by avoiding sutures at the nerve repair site and utilizing the advantages of a conduit-based repair. The left sciatic nerves of female Sprague-Dawley rats were transected and repaired using a novel conduit-based device. The conduit-based device group was compared to a control group of rats that underwent a standard end-to-end microsurgical repair of the sciatic nerve. Animals underwent behavioral assessments at weekly intervals post-operatively using the sciatic functional index (SFI) test. Animals were sacrificed at four weeks to obtain motor axon counts from immunohistochemistry. A sub-group of animals were sacrificed immediately post repair to obtain MRI images. SFI scores were superior in rats which received conduit-based repairs compared to the control group. Motor axon counts distal to the injury in the device group at four weeks were statistically superior to the control group. MRI tractography was used to demonstrate repair of two nerves using the novel conduit device. A conduit-based nerve coaptation device avoids sutures at the nerve repair site and leads to improved outcomes in a rat model. Conduit-based nerve repair devices have the potential to standardize nerve repairs while improving outcomes.

Double-strand break repair-adox: Restoration of suppressed double-strand break repair during mitosis induces genomic instability.

Science.gov (United States)

Terasawa, Masahiro; Shinohara, Akira; Shinohara, Miki

2014-12-01

Double-strand breaks (DSBs) are one of the severest types of DNA damage. Unrepaired DSBs easily induce cell death and chromosome aberrations. To maintain genomic stability, cells have checkpoint and DSB repair systems to respond to DNA damage throughout most of the cell cycle. The failure of this process often results in apoptosis or genomic instability, such as aneuploidy, deletion, or translocation. Therefore, DSB repair is essential for maintenance of genomic stability. During mitosis, however, cells seem to suppress the DNA damage response and proceed to the next G1 phase, even if there are unrepaired DSBs. The biological significance of this suppression is not known. In this review, we summarize recent studies of mitotic DSB repair and discuss the mechanisms of suppression of DSB repair during mitosis. DSB repair, which maintains genomic integrity in other phases of the cell cycle, is rather toxic to cells during mitosis, often resulting in chromosome missegregation and aberration. Cells have multiple safeguards to prevent genomic instability during mitosis: inhibition of 53BP1 or BRCA1 localization to DSB sites, which is important to promote non-homologous end joining or homologous recombination, respectively, and also modulation of the non-homologous end joining core complex to inhibit DSB repair. We discuss how DSBs during mitosis are toxic and the multiple safeguard systems that suppress genomic instability. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Urinary function after Snodgrass repair of distal hypospadias: comparison with the Mathieu repair.

Science.gov (United States)

Scarpa, Maria Grazia; Castagnetti, Marco; Berrettini, Alfredo; Rigamonti, Waifro; Musi, Luciano

2010-05-01

To evaluate urinary function in patients with distal hypospadias undergoing repair by the tubularized incised-plate urethroplasty (TIP or Snodgrass), compare the results with those in patients treated by the Mathieu technique, and show the potential issues inherent to the evaluation of such results. A cross-sectional assessment was performed of uncomplicated distal hypospadias operated on during a 3-year period, already toilet trained, and able to void volitionally. Evaluation included clinical assessment urinary symptoms and urinary stream, and uroflowmetry. Out of 83 patients operated on during the study period, 10 (12%) developed complication and 32 were not toilet trained or refused to participate in the study. Median follow-up in the remaining 41 patients included in the study was 20 (3-36) months. None of these patients presented voiding symptoms or urinary stream abnormalities. Uroflowmetry was normal in 30 cases and obstructive in 11 (27%). An obstructive flow pattern was more common in patients undergoing TIP versus Mathieu repair, 8 of 19 (42%) versus 3 of 22 (14%), respectively (P = 0.07). Four TIP cases with an obstructive uroflow pattern were managed conservatively. Although both the TIP and the Mathieu repair allow good results in terms of urinary function after distal hypospadias repairs, the TIP technique seems more likely to be associated with urine flow pattern abnormalities. The actual clinical relevance of this finding remains ill defined.

Metabolite damage and repair in metabolic engineering design.

Science.gov (United States)

Sun, Jiayi; Jeffryes, James G; Henry, Christopher S; Bruner, Steven D; Hanson, Andrew D

2017-11-01

The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields, and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects. Copyright © 2017 International Metabolic Engineering Society. All rights reserved.

High performance repairing of reinforced concrete structures

International Nuclear Information System (INIS)

Iskhakov, I.; Ribakov, Y.; Holschemacher, K.; Mueller, T.

2013-01-01

Highlights: ► Steel fibered high strength concrete is effective for repairing concrete elements. ► Changing fibers’ content, required ductility of the repaired element is achieved. ► Experiments prove previously developed design concepts for two layer beams. -- Abstract: Steel fibered high strength concrete (SFHSC) is an effective material that can be used for repairing concrete elements. Design of normal strength concrete (NSC) elements that should be repaired using SFHSC can be based on general concepts for design of two-layer beams, consisting of SFHSC in the compressed zone and NSC without fibers in the tensile zone. It was previously reported that such elements are effective when their section carries rather large bending moments. Steel fibers, added to high strength concrete, increase its ultimate deformations due to the additional energy dissipation potential contributed by fibers. When changing the fibers’ content, a required ductility level of the repaired element can be achieved. Providing proper ductility is important for design of structures to dynamic loadings. The current study discusses experimental results that form a basis for finding optimal fiber content, yielding the highest Poisson coefficient and ductility of the repaired elements’ sections. Some technological issues as well as distribution of fibers in the cross section of two-layer bending elements are investigated. The experimental results, obtained in the frame of this study, form a basis for general technological provisions, related to repairing of NSC beams and slabs, using SFHSC.

The cutting edges in DNA repair, licensing, and fidelity: DNA and RNA repair nucleases sculpt DNA to measure twice, cut once.

Science.gov (United States)

Tsutakawa, Susan E; Lafrance-Vanasse, Julien; Tainer, John A

2014-07-01

To avoid genome instability, DNA repair nucleases must precisely target the correct damaged substrate before they are licensed to incise. Damage identification is a challenge for all DNA damage response proteins, but especially for nucleases that cut the DNA and necessarily create a cleaved DNA repair intermediate, likely more toxic than the initial damage. How do these enzymes achieve exquisite specificity without specific sequence recognition or, in some cases, without a non-canonical DNA nucleotide? Combined structural, biochemical, and biological analyses of repair nucleases are revealing their molecular tools for damage verification and safeguarding against inadvertent incision. Surprisingly, these enzymes also often act on RNA, which deserves more attention. Here, we review protein-DNA structures for nucleases involved in replication, base excision repair, mismatch repair, double strand break repair (DSBR), and telomere maintenance: apurinic/apyrimidinic endonuclease 1 (APE1), Endonuclease IV (Nfo), tyrosyl DNA phosphodiesterase (TDP2), UV Damage endonuclease (UVDE), very short patch repair endonuclease (Vsr), Endonuclease V (Nfi), Flap endonuclease 1 (FEN1), exonuclease 1 (Exo1), RNase T and Meiotic recombination 11 (Mre11). DNA and RNA structure-sensing nucleases are essential to life with roles in DNA replication, repair, and transcription. Increasingly these enzymes are employed as advanced tools for synthetic biology and as targets for cancer prognosis and interventions. Currently their structural biology is most fully illuminated for DNA repair, which is also essential to life. How DNA repair enzymes maintain genome fidelity is one of the DNA double helix secrets missed by James Watson and Francis Crick, that is only now being illuminated though structural biology and mutational analyses. Structures reveal motifs for repair nucleases and mechanisms whereby these enzymes follow the old carpenter adage: measure twice, cut once. Furthermore, to measure

Homozygous germ-line mutation of the PMS2 mismatch repair gene: a unique case report of constitutional mismatch repair deficiency (CMMRD)

OpenAIRE

Ramchander, N. C.; Ryan, N. A. J.; Crosbie, E. J.; Evans, D. G.

2017-01-01

BackgroundConstitutional mismatch repair deficiency syndrome results from bi-allelic inheritance of mutations affecting the key DNA mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. Individuals with bi-allelic mutations have a dysfunctional mismatch repair system from birth; as a result, constitutional mismatch repair deficiency syndrome is characterised by early onset malignancies. Fewer than 150 cases have been reported in the literature over the past 20 years. This is the first report of th...

A new barbed device for repair of flexor tendons.

LENUS (Irish Health Repository)

Hirpara, K M

2012-02-01

We split 100 porcine flexor tendons into five groups of 20 tendons for repair. Three groups were repaired using the Pennington modified Kessler technique, the cruciate or the Savage technique, one using one new device per tendon and the other with two new devices per tendon. Half of the tendons received supplemental circumferential Silfverskiold type B cross-stitch. The repairs were loaded to failure and a record made of their bulk, the force required to produce a 3 mm gap, the maximum force applied before failure and the stiffness. When only one device was used repairs were equivalent to the Pennington modified Kessler for all parameters except the force to produce a 3 mm gap when supplemented with a circumferential repair, which was equivalent to the cruciate. When two devices were used the repair strength was equivalent to the cruciate repair, and when the two-device repair was supplemented with a circumferential suture the force to produce a 3 mm gap was equivalent to that of the Savage six-strand technique.

Physical interaction between components of DNA mismatch repair and nucleotide excision repair

International Nuclear Information System (INIS)

Bertrand, P.; Tishkoff, D.X.; Filosi, N.; Dasgupta, R.; Kolodner, R.D.

1998-01-01

Nucleotide excision repair (NER) and DNA mismatch repair are required for some common processes although the biochemical basis for this requirement is unknown. Saccharomyces cerevisiae RAD14 was identified in a two-hybrid screen using MSH2 as 'bait,' and pairwise interactions between MSH2 and RAD1, RAD2, RAD3, RAD10, RAD14, and RAD25 subsequently were demonstrated by two-hybrid analysis. MSH2 coimmunoprecipitated specifically with epitope-tagged versions of RAD2, RAD10, RAD14, and RAD25. MSH2 and RAD10 were found to interact in msh3 msh6 and mlh1 pms1 double mutants, suggesting a direct interaction with MSH2. Mutations in MSH2 increased the UV sensitivity of NER-deficient yeast strains, and msh2 mutations were epistatic to the mutator phenotype observed in NER-deficient strains. These data suggest that MSH2 and possibly other components of DNA mismatch repair exist in a complex with NER proteins, providing a biochemical and genetical basis for these proteins to function in common processes

Rotator Cuff Repair in Adolescent Athletes.

Science.gov (United States)

Azzam, Michael G; Dugas, Jeffrey R; Andrews, James R; Goldstein, Samuel R; Emblom, Benton A; Cain, E Lyle

2018-04-01

Rotator cuff tears are rare injuries in adolescents but cause significant morbidity if unrecognized. Previous literature on rotator cuff repairs in adolescents is limited to small case series, with few data to guide treatment. Adolescent patients would have excellent functional outcome scores and return to the same level of sports participation after rotator cuff repair but would have some difficulty with returning to overhead sports. Case series; Level of evidence 4. A retrospective search of the practice's billing records identified all patients participating in at least 1 sport who underwent rotator cuff repair between 2006 and 2014 with an age Rotator Cuff Index. Thirty-two consecutive adolescent athletes (28 boys and 4 girls) with a mean age of 16.1 years (range, 13.2-17.9 years) met inclusion criteria. Twenty-nine patients (91%) had a traumatic event, and 27 of these patients (93%) had no symptoms before the trauma. The most common single tendon injury was to the supraspinatus (21 patients, 66%), of which 2 were complete tendon tears, 1 was a bony avulsion of the tendon, and 18 were high-grade partial tears. Fourteen patients (56%) underwent single-row repair of their rotator cuff tear, and 11 (44%) underwent double-row repair. All subscapularis injuries were repaired in open fashion, while all other tears were repaired arthroscopically. Twenty-seven patients (84%) completed the outcome questionnaires at a mean 6.2 years after surgery (range, 2-10 years). The mean ASES score was 93 (range, 65-100; SD = 9); mean Western Ontario Rotator Cuff Index, 89% (range, 60%-100%; SD = 13%); and mean numeric pain rating, 0.3 (range, 0-3; SD = 0.8). Overall, 25 patients (93%) returned to the same level of play or higher. Among overhead athletes, 13 (93%) were able to return to the same level of play, but 8 (57%) were forced to change positions. There were no surgical complications, but 2 patients did undergo a subsequent operation. Surgical repair of high-grade partial

Part II: Biomechanical assessment for a footprint-restoring transosseous-equivalent rotator cuff repair technique compared with a double-row repair technique.

Science.gov (United States)

Park, Maxwell C; Tibone, James E; ElAttrache, Neal S; Ahmad, Christopher S; Jun, Bong-Jae; Lee, Thay Q

2007-01-01

We hypothesized that a transosseous-equivalent repair would demonstrate improved tensile strength and gap formation between the tendon and tuberosity when compared with a double-row technique. In 6 fresh-frozen human shoulders, a transosseous-equivalent rotator cuff repair was performed: a suture limb from each of two medial anchors was bridged over the tendon and fixed laterally with an interference screw. In 6 contralateral matched-pair specimens, a double-row repair was performed. For all repairs, a materials testing machine was used to load each repair cyclically from 10 N to 180 N for 30 cycles; each repair underwent tensile testing to measure failure loads at a deformation rate of 1 mm/sec. Gap formation between the tendon edge and insertion was measured with a video digitizing system. The mean ultimate load to failure was significantly greater for the transosseous-equivalent technique (443.0 +/- 87.8 N) compared with the double-row technique (299.2 +/- 52.5 N) (P = .043). Gap formation during cyclic loading was not significantly different between the transosseous-equivalent and double-row techniques, with mean values of 3.74 +/- 1.51 mm and 3.79 +/- 0.68 mm, respectively (P = .95). Stiffness for all cycles was not statistically different between the two constructs (P > .40). The transosseous-equivalent rotator cuff repair technique improves ultimate failure loads when compared with a double-row technique. Gap formation is similar for both techniques. A transosseous-equivalent repair helps restore footprint dimensions and provides a stronger repair than the double-row technique, which may help optimize healing biology.

75 FR 39524 - Lead-Based Paint Renovation, Repair and Painting, and Pre-Renovation Education Activities in...

Science.gov (United States)

2010-07-09

..., Repair and Painting, and Pre- Renovation Education Activities in Target Housing and Child Occupied... pre-renovation education program in accordance with section 406(b) of TSCA, 15 U.S.C. 2686(b). This... and child-occupied facilities in the State of Oregon. Individuals and firms falling under the North...

76 FR 27044 - Lead-Based Paint Renovation, Repair and Painting, and Pre-Renovation Education Activities in...

Science.gov (United States)

2011-05-10

..., Repair and Painting, and Pre- Renovation Education Activities in Target Housing and Child Occupied...), and a lead-based paint pre-renovation education program in accordance with section 406(b) of TSCA, 15... renovation and remodeling activities of pre-1978 housing and child-occupied facilities in the State of...

DNA repair in ultraviolet-irradiated spores of Bacillus subtilis

International Nuclear Information System (INIS)

Wang, T.C.V.

1976-01-01

It has been shown previously by others that at least two independent repair mechanisms are present in Bacillus subtilis for removing ''spore photoproduct'' from DNA of ultraviolet (254 nm)-irradiated spores after germination. One of these, designated as ''spore repair,'' is shown in this study to restore ''spore photoproduct'' to two thymine residues, leaving the DNA backbone intact at the end of the process in vivo. The circumstances under which this repair can occur and some characteristics of its energy requirements have been clarified. The second repair process is identified as excision repair, which can excise both ''spore photoproduct'' from DNA of irradiated spores and cyclobutane-type pyrimidine dimers from DNA of irradiated vegetative cells. In this study it is shown that the gene hcr 1 affects an enzyme activity for the incision step initiating this repair, while the gene hcr 42 affects a step subsequent to incision in the mechanism. In addition a third, independent repair system, termed ''germinative excision repair,'' is discovered and shown to be specific for excising only cyclobutane-type pyrimidine dimers but not ''spore photoproduct.'' This repair system is responsible for the observed high ultraviolet-resistance and temporary capacity for host cell reactivation on recently germinated spores of Bacillus subtilis HCR - strains

Flexural strength of structural concrete repaired with HBPMM cement

International Nuclear Information System (INIS)

Memon, G.H.; Khaskheli, G.B.; Kumar, A.

2009-01-01

To repair damaged concrete structures, Dadabhoy Cement Factory in Sindh has launched a product known as HBPMM (Hi-Bond Polymer Modified Mortar) cement. HBPMM is used to repair various concrete structures in Pakistan but the experimental back up regarding the real performance of the product, as far as flexural strength of concrete is concerned, is not well known yet. This study is thus aimed to investigate the flexural strength of structural concrete repaired with HBPMM compared to that repaired with OPC (Ordinary Portland Cement). In total 32 concrete beams (6x6x18) having compressive strength of 3000 and 5000 psi were manufactured. To obtain flexural strength of the beams, these were splitted by using a UTM (Universal Testing Machine). Beams were then repaired with different applications of HBPMM and OPC. After 28 days of curing, the repaired beams were re-splitted to determine the flexural strength of repaired beams. Results show that both HBPMM and OPC are not very effective. However, the performance of HBPMM remained slightly better than that of OPC. Both OPC and HBPMM remained more efficient in case of 5000 psi concrete than that of 3000 psi concrete. Flexural strength of repaired beams could be increased by increasing application of the repairing material. (author)

Human diseases with genetically altered DNA repair processes

International Nuclear Information System (INIS)

Cleaver, J.E.; Bootsma, D.; Friedberg, E.

1975-01-01

DNA repair of single-strand breaks (produced by ionizing radiation) and of base damage (produced by ultraviolet (uv) light) are two repair mechanisms that most mammalian cells possess. Genetic defects in these repair mechanisms are exemplified by cells from the human premature-aging disease, progeria, which fail to rejoin single-strand breaks, and the skin disease, xeroderma pigmentosum (XP), which exhibits high actinic carcinogenesis and involves failure to repair base damage. In terms of the response of XP cells, many chemical carcinogens can be classified as either x-ray-like (i.e., they cause damage that XP cells can repair) or uv-like (i.e., they cause damage that XP cells cannot repair). The first group contains some of the more strongly carcinogenic chemicals (e.g., alkylating agents). XP occurs in at least two clinical forms, and somatic cell hybridization indicates at least three complementation groups. In order to identify cell lines from various different laboratories unambiguously, a modified nomenclature of XP lines is proposed. (U.S.)

Human diseases with genetically altered DNA repair processes

International Nuclear Information System (INIS)

Cleaver, J.E.; Bootsma, D.; Friedberg, E.

1975-01-01

DNA repair of single-strand breaks (produced by ionizing radiation) and of base damage (produced by ultraviolet (UV) light) are two repair mechanisms that most mammalian cells possess. Genetic defects in these repair mechanisms are exemplified by cells from the human premature-aging disease, progeria, which fail to rejoin single-strand breaks, and the skin disease, xeroderma pigmentosum (XP), which exhibits high actinic carcinogenesis and involves failure to repair base damage. In terms of the response of XP cells, many chemical carcinogens can be classified as either X-ray-like (i.e., they cause damage that XP cells can repair) or UV-like (i.e., they cause damage that XP cells cannot repair). The first group contains some of the more strongly carcinogenic chemicals (e.g., alkylating agents). XP occurs in at least two clinical forms, and somatic cell hybridization indicates at least three complementation groups. In order to identify cell lines from various different laboratories unambiguously, a modified nomenclature of XP lines is proposed

Programming Programmable Logic Controller. High-Technology Training Module.

Science.gov (United States)

Lipsky, Kevin

This training module on programming programmable logic controllers (PLC) is part of the memory structure and programming unit used in a packaging systems equipment control course. In the course, students assemble, install, maintain, and repair industrial machinery used in industry. The module contains description, objectives, content outline,…

Wide Panel Testing Technique for Evaluating Repair Weld Strengths

Science.gov (United States)

Rogers, Patrick R.; Bynum, Julian E.; Shah, Sandeep R.

1998-01-01

This paper describes a new tensile testing technique for evaluating the overall effect of a repair weld on the strength of a welded joint. Previously, repair weld strengths have been evaluated using one-inch width tensile specimens, but this technique does not capture all of the effects that result from a repair. The new technique involves testing of "wide panel" tensile specimens which contain the full length of a repair weld within a longer initial weld, allowing the specimen to capture the combined effects of residual stresses, local strength degradation, and load redistribution around a repair. The development of strains in the repair area of standard aluminum alloy specimens and new high-performance aluminum-lithium alloy specimens was observed and evaluated using photoelastic material. The results of this evaluation show an increased sensitivity to repair welding residual stresses in the aluminum-lithium alloy specimens.

Testing of self-repairing composite airplane components by use of CAI and the release of the repair chemicals from carefully inserted small tubes

Science.gov (United States)

Dry, Carolyn

2007-04-01

The research on self repair of airplane components, under an SBIR phase II with Wright Patterson Air Force Base, has investigated the attributes and best end use applications for such a technology. These attributes include issues related to manufacturability, cost, potential benefits such as weight reduction, and cost reduction. The goal of our research has been to develop self-repairing composites with unique strength for air vehicles. Our revolutionary approach involves the autonomous release of repair chemicals from within the composite matrix itself. The repair agents are contained in hollow, structural fibers that are embedded within the matrix. Under stress, the composite senses external environmental factors and reacts by releasing the repair agents from within the hollow vessels. This autonomous response occurs wherever and whenever cracking, debonding or other matrix damage transpires. Superior performance over the life of the composite is achieved through this self-repairing mechanism. The advantages to the military would be safely executed missions, fewer repairs and eventually lighter vehicles. In particular the research has addressed the issues by correlating the impact of the various factors, such as 1) delivery vessel placement, shape/size and effect on composite strength, chemicals released and their effect on the matrix, release trigger and efficacy and any impact on matrix properties 2) impact of composite processing methods that involve heat and pressure on the repair vessels. Our self repairing system can be processed at temperatures of 300-350F, repairs in less than 30 seconds and does not damage the composite by repair fiber insertion or chemical release. Scaling up and manufacture of components has revealed that anticipating potential problems allowed us to avoid those associated with processing temperatures and pressures. The presentation will focus on compression after impact testing and the placement of repair fibers/tubes into prepreg

Mechanical characterization of composite repairs for fiberglass wind turbine blades

Science.gov (United States)

Chawla, Tanveer Singh

While in service, wind turbine blades experience various modes of loading. An example is impact loading in the form of hail or bird strikes, which might lead to localized damage or formation of cracks a few plies deep on the blade surface. One of the methods to conduct repairs on wind turbine blades that are damaged while in service is hand lay-up of the repair part after grinding out the damaged portion and some of its surrounding area. The resin used for such repairs usually differs from the parent plate resin in composition and properties such as gel time, viscosity, etc. As a result the properties of the repaired parts are not the same as that of the undamaged blades. Subsequent repetitive loading can be detrimental to weak repairs to such an extent so as to cause delamination at the parent-repair bondline causing the repairs to eventually fall off the blade. Thus the strength and toughness of the repair are of critical importance. Initial part of this work consists of an effort to increase repair strength by identifying an optimum hand layup repair resin for fiberglass wind turbine blades currently being manufactured by a global company. As delamination of the repair from the parent blade is a major concern and unidirectional glass fibers along with a polymer resin are used to manufacture blades under consideration, testing method detailed in ASTM D 5528 (Test Method for Mode I Interlaminar Fracture Toughness of Unidirectional Fiber-Reinforced Polymer Matrix Composites) was followed to determine propagation fracture toughness values of the prospective vinyl ester repair resin candidates. These values were compared to those for a base polyester repair resin used by the company. Experimental procedure and results obtained from the above mentioned testing using double cantilever beam (DCB) specimens are detailed. Three new repair resins were shortlisted through mode I testing. It was also found that variation in the depth of the ground top ply of the parent part

The forked flap repair for hypospadias

Directory of Open Access Journals (Sweden)

Anil Chadha

2012-01-01

Full Text Available Context: Despite the abundance of techniques for the repair of Hypospadias, its problems still persist and a satisfactory design to correct the penile curvature with the formation of neourethra from the native urethral tissue or genital or extragenital tissues, with minimal postoperative complications has yet to evolve. Aim: Persisting with such an endeavor, a new technique for the repair of distal and midpenile hypospadias is described. Materials and Methods: The study has been done in 70 cases over the past 11 years. The "Forked-Flap" repair is a single stage method for the repair of such Hypospadias with chordee. It takes advantage of the rich vascular communication at the corona and capitalizes on the established reliability of the meatal based flip-flap. The repair achieves straightening of the curvature of the penis by complete excision of chordee tissue from the ventral surface of the penis beneath the urethral plate. The urethra is reconstructed using the native plate with forked flap extensions and genital tissue relying on the concept of meatal based flaps. Water proofing by dartos tissue and reinforcement by Nesbit′s prepucial tissue transfer completes the one stage procedure. Statistical Analysis: An analysis of 70 cases of this single stage technique of repair of penile hypospadias with chordee, operated at 3 to 5 years of age over the past 11 years is presented. Results and Conclusion: The Forked Flap gives comparable and replicable results; except for a urethrocutaneous fistula rate of 4% no other complications were observed.

Vesicovaginal fistula repair through vaginal approach

International Nuclear Information System (INIS)

Ashraf, S.; Rahim, J.

2014-01-01

Objectives: To evaluate the outcome of trans-vaginal repair of vesico-vaginal fistula through vaginal approach. Study Design: Prospective study. Material and Methods: This study was carried out in Department of Urology, Shaikh Zayed Postgraduate Medical Institute and National institute of Kidney Diseases, Lahore for the period extending from April 2009 to April 2014. Total 17 patients were included in the study. History, physical examination and findings on investigations were reviewed. In all patients cystoscopy and vaginal examination was performed to see fistula site and ureteral orfices. Then trans-vaginal repair was done in all cases. Results: VVF repair was performed on 17 patients aging 25 to 45 years (mean 35.83 ± 7.37 years). The symptoms preceded for a period of 3 months to 8 years. The cause was gynecological hysterectomy 8 (47.05%), obstetric C-section 7 (41.17%) and obstructed labor 2(11.76%). In three of our patients VVF was previously repaired trans-abdominally. On cystoscopy no patients had more than one fistula. In two (11.76%) patients fistula was supratrigonal. The average size of fistula was 2.05 em, detail of fistula site and size is given in table. One patient had leakage on second postop day that was managed with change of Foleys catheter. Successful repair was achieved in all patients and no patient required second attempt. No ureteric injury and other complications were observed. Conclusion: Trans-vaginal repair of VVF avoid laparotomy and bladder bisection. It has reduced hospital stay and morbidity. (author)

Regulatory Challenges for Cartilage Repair Technologies.

Science.gov (United States)

McGowan, Kevin B; Stiegman, Glenn

2013-01-01

In the United States, few Food and Drug Administration (FDA)-approved options exist for the treatment of focal cartilage and osteochondral lesions. Developers of products for cartilage repair face many challenges to obtain marketing approval from the FDA. The objective of this review is to discuss the necessary steps for FDA application and approval for a new cartilage repair product. FDA Guidance Documents, FDA Panel Meetings, scientific organization recommendations, and clinicaltrials.gov were reviewed to demonstrate the current thinking of FDA and the scientific community on the regulatory process for cartilage repair therapies. Cartilage repair therapies can receive market approval from FDA as medical devices, drugs, or biologics, and the specific classification of product can affect the nonclinical, clinical, and regulatory strategy to bring the product to market. Recent FDA guidance gives an outline of the required elements to bring a cartilage repair product to market, although these standards are often very general. As a result, companies have to carefully craft their study patient population, comparator group, and clinical endpoint to best showcase their product's attributes. In addition, regulatory strategy and manufacturing process validation need to be considered early in the clinical study process to allow for timely product approval following the completion of clinical study. Although the path to regulatory approval for a cartilage repair therapy is challenging and time-consuming, proper clinical trial planning and attention to the details can eventually save companies time and money by bringing a product to the market in the most expeditious process possible.

29 CFR 541.401 - Computer manufacture and repair.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Computer manufacture and repair. 541.401 Section 541.401... SALES EMPLOYEES Computer Employees § 541.401 Computer manufacture and repair. The exemption for employees in computer occupations does not include employees engaged in the manufacture or repair of...

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair

Science.gov (United States)

Lightsey, Harry M.; Kantrowitz, David E.; Swindell, Hasani W.; Trofa, David P.; Ahmad, Christopher S.; Lynch, T. Sean

2018-01-01

Background: The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. Purpose: To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Study Design: Cross-sectional study. Methods: Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Results: Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises

Midwives conducting perineal repair: The Danish Suture Trial

DEFF Research Database (Denmark)

Kindberg, Sara

2007-01-01

Midwives conducting perineal repair: The Danish Suture Trial.     Background Suture techniques and materials for repair of 2nd degree perineal lacerations and episiotomies have been tested in several clinical trials. Danish midwives and obstetricians have developed a new, simple and time-efficien......Midwives conducting perineal repair: The Danish Suture Trial.     Background Suture techniques and materials for repair of 2nd degree perineal lacerations and episiotomies have been tested in several clinical trials. Danish midwives and obstetricians have developed a new, simple and time...

Patient and Aneurysm Characteristics Predicting Prolonged Length of Stay After Elective Open AAA Repair in the Endovascular Era.

Science.gov (United States)

Casillas-Berumen, Sergio; Rojas-Miguez, Florencia A; Farber, Alik; Komshian, Sevan; Kalish, Jeffrey A; Rybin, Denis; Doros, Gheorghe; Siracuse, Jeffrey J

2018-01-01

Open aortic aneurysm repair (AAA) repair can be resource intensive and associated with a prolonged length of stay (LOS). We sought to examine patient and aneurysm predictors of prolonged LOS to better identify those at risk in the preoperative setting. Patient data were obtained from the targeted AAA American College of Surgery National Surgical Quality Improvement Program database from 2012 to 2014 of patients undergoing open AAA repair. Multivariable logistic regression was used to determine predictors of prolonged postoperative LOS defined as greater than 10 days (75th percentile). There were 1172 open AAA repairs identified. The majority (54%) of patients were older than 70 years and male (74%). Surgical approach was transperitoneal (70.9%) and retroperitoneal (29.1%). Aneurysms were 51.4% infrarenal, 33% juxtarenal, 5.7% pararenal, 7.4% suprarenal, and 2.5% type IV thoracoabdominal. Mean and median LOS were 9.1 ± 7.4 and 7 (0-72) days, respectively. Independently associated with extended LOS factors were visceral revascularization (odds ratio [OR]: 5.32, 95% confidence interval [CI]: 2.77-10.22, P AAA repair. Prospective identification of high-risk patients may allow physicians and hospitals to engage in multidisciplinary collaborations preoperatively to try to improve LOS in this resource-intensive population.

DNA repair: a changing geography? (1964-2008).

Science.gov (United States)

Maisonobe, Marion; Giglia-Mari, Giuseppina; Eckert, Denis

2013-07-01

This article aims to explain the current state of DNA Repair studies' global geography by focusing on the genesis of the community. Bibliometric data is used to localize scientific activities related to DNA Repair at the city level. The keyword "DNA Repair" was introduced first by American scientists. It started to spread after 1964 that is to say, after P. Howard-Flanders (Yale University), P. Hanawalt (Stanford University) and R. Setlow (Oak Ridge Laboratories) found evidence for Excision Repair mechanisms. It was the first stage in the emergence of an autonomous scientific community. In this article, we will try to assess to what extent the geo-history of this scientific field is determinant in understanding its current geography. In order to do so, we will localize the places where the first "DNA Repair" publications were signed fifty years ago and the following spatial diffusion process, which led to the current geography of the field. Then, we will focus on the evolution of the research activity of "early entrants" in relation to the activity of "latecomers". This article is an opportunity to share with DNA Repair scientists some research results of a dynamic field in Science studies: spatial scientometrics. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimal Overhaul-Replacement Policies for Repairable Machine Sold with Warranty

Directory of Open Access Journals (Sweden)

Kusmaningrum Soemadi

2014-12-01

Full Text Available This research deals with an overhaul-replacement policy for a repairable machine sold with Free Replacement Warranty (FRW. The machine will be used for a finite horizon, T (T <, and evaluated at a fixed interval, s (s< T. At each evaluation point, the buyer considers three alternative decisions i.e. Keep the machine, Overhaul it, or Replace it with a new identical one. An overhaul can reduce the machine age virtually, but not to a point that the machine is as good as new. If the machine fails during the warranty period, it is rectified at no cost to the buyer. Any failure occurring before and after the expiry of the warranty is restored by minimal repair. An overhaul-replacement policy is formulated for such machines by using dynamic programming approach to obtain the buyer’s optimal policy. The results show that a significant rejuvenation effect due to overhaul may extend the length of machine life cycle and delay the replacement decision. In contrast, the warranty stimulates early machine replacement and by then increases the replacement frequencies for a certain range of replacement cost. This demonstrates that to minimize the total ownership cost over T the buyer needs to consider the minimal repair cost reduction due to rejuvenation effect of overhaul as well as the warranty benefit due to replacement. Numerical examples are presented for both illustrating the optimal policy and describing the behavior of the optimal solution.

Functional Outcomes and Return to Sports After Acute Repair, Chronic Repair, and Allograft Reconstruction for Proximal Hamstring Ruptures.

Science.gov (United States)

Rust, David A; Giveans, M Russell; Stone, Rebecca M; Samuelson, Kathryn M; Larson, Christopher M

2014-06-01

There are limited data regarding outcomes and return to sports after surgery for acute versus chronic proximal hamstring ruptures. Surgery for chronic proximal hamstring ruptures leads to improved outcomes and return to sports but at a lower level than with acute repair. Proximal hamstring reconstruction with an Achilles allograft for chronic ruptures is successful when direct repair is not possible. Cohort study; Level of evidence, 3. Between 2002 and 2012, a total of 72 patients with a traumatic proximal hamstring rupture (51 acute, 21 chronic) underwent either direct tendon repair with suture anchors (n = 58) or Achilles allograft tendon reconstruction (n = 14). Results from the Single Assessment Numeric Evaluation (SANE) for activities of daily living (ADL) and sports-related activities, Short Form-12 (SF-12), visual analog scale (VAS), and a patient satisfaction questionnaire were obtained. The mean time to surgery in the chronic group was 441.4 days versus 17.8 days in the acute group. At a mean follow-up of 45 months, patients with chronic tears had inferior sports activity scores (70.2% vs 80.3%, respectively; P = .026) and a trend for decreased ADL scores (86.5% vs 93.3%, respectively; P = .085) compared with those with acute tears. Patients with chronic tears, however, reported significant improvements postoperatively for both sports activity scores (30.3% to 70.2%; P sports activity scores equal to those of chronic repair (P = .507 and P = .904, respectively). There were no significant differences between groups in SF-12, VAS, or patient satisfaction outcomes (mean, 85.2% satisfaction overall). Acute repair was superior to chronic surgery with regard to return to sports. Acute and chronic proximal hamstring repair and allograft reconstruction had favorable results for ADL. For low-demand patients or those with medical comorbidities, delayed repair or reconstruction might be considered with an expected 87% return to normal ADL. For patients who desire to

Potentially lethal damage and its repair

International Nuclear Information System (INIS)

Utsumi, Hiroshi

1989-01-01

Two forms termed fast-and slow-potentially lethal lethal damage (PLD) are introduced and discussed. The effect on the survival of x-irradiated Chinese hamster cells (V79) of two different post-treatments is examined in plateau- and in log-phases of growth. The postirradiation treatments used : a) incubation in hypertonic solution, and b) incubation in conditioned medium obtained from plateau-phase. Similar reduction in survival was caused by postirradiation treatment with hypertonic phosphate buffered saline, and similar increased in survival was effected by treatment in conditioned medium in plateau- and in log-phases cells. However, repair of PLD sensitive to hypertonic treatment was faster (half time, 5-10 min)(f-PLD repair) and independent from the repair of PLD (half time, 1-2 hour)(s-PLD repair) observed in conditioned medium. The results indicate the induction of two forms of PLD by radiation. Induction of both PLD was found to decrease with increasing LET of the radiation used. Identification of the molecular processes underlying repair and fixation of PLD is a task of particular interest, since it may allow replacement of a phenomenological definition with a molecular definition. Evidence is reviewed indicating the DNA double strand breaks (directly or indirectly induced) may be the DNA lesions underlying PLD. (author)

Remote repair of the dissolvers in Tokai reprocessing plant

International Nuclear Information System (INIS)

Otani, Yosikuni

1985-01-01

In the Tokai fuel reprocessing plant, there occurred failures (pinholes) in two dissolver tanks successively in 1982 and 1983. These dissolvers are set under high radiation field, not permitting access of the personnel. So, repair works were carried out after development of the remotely operated repair system. For repair of the failed dissolver tanks, after tests and studies, the means was employed of grinding off the wall surface to small depth and then forming over it a corrosion resistant sealing layer by padding welding. The repair system which enabled the repair and the inspection in the cell by remote operation consisted of six devices including polishing, welding, dye penetration test, etc. Repair works on the dissolvers took two months and a half from September 1983. (Mori, K.)

Anterior cruciate ligament repair - past, present and future.

Science.gov (United States)

Mahapatra, Piyush; Horriat, Saman; Anand, Bobby S

2018-06-15

This article provides a detailed narrative review on the history and current concepts surrounding ligamentous repair techniques in athletic patients. In particular, we will focus on the anterior cruciate ligament (ACL) as a case study in ligament injury and ligamentous repair techniques. PubMed (MEDLINE), EMBASE and Cochrane Library databases for papers relating to primary anterior cruciate ligament reconstruction were searched by all participating authors. All relevant historical papers were included for analysis. Additional searches of the same databases were made for papers relating to biological enhancement of ligament healing. The poor capacity of the ACL to heal is one of the main reasons why the current gold standard surgical treatment for an ACL injury in an athletic patient is ACL reconstruction with autograft from either the hamstrings or patella tendon. It is hypothesised that by preserving and repairing native tissues and negating the need for autograft that primary ACL repair may represent a key step change in the treatment of ACL injuries. The history of primary ACL repair will be discussed and the circumstances that led to the near-abandonment of primary ACL repair techniques will be reviewed. There has been a recent resurgence in interest with regards to primary ACL repair. Improvements in imaging now allow for identification of tear location, with femoral-sided injuries, being more suitable for repair. We will discuss in details strategies for improving the mechanical and biological environment in order to allow primary healing to occur. In particular, we will explain mechanical supplementation such as Internal Brace Ligament Augmentation and Dynamic Intraligamentary Stabilisation techniques. These are novel techniques that aim to protect the primary repair by providing a stabilising construct that connects the femur and the tibia, thus bridging the repair. In addition, biological supplementation is being investigated as an adjunct and we will

Nucleotide excision repair in the test tube.

NARCIS (Netherlands)

N.G.J. Jaspers (Nicolaas); J.H.J. Hoeijmakers (Jan)

1995-01-01

textabstractThe eukaryotic nucleotide excision-repair pathway has been reconstituted in vitro, an achievement that should hasten the full enzymological characterization of this highly complex DNA-repair pathway.

General Mechanical Repair. Minor Automotive Maintenance, Small Engine [Repair, and] Welding: Curriculum Guide and Lesson Plans.

Science.gov (United States)

Hamlin, Larry

This document contains a curriculum guide and lesson plans for a general mechanical repair course with three sections: minor automotive maintenance, small engine repair, and welding. The curriculum guide begins with a matrix that relates the lesson plans to essential elements of math, science, language arts, and social studies and to Texas…

Motorcycle Repair.

Science.gov (United States)

Hein, Jim; Bundy, Mike

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

Repairing liner of the reactor; Reparacion del liner del reactor

Energy Technology Data Exchange (ETDEWEB)

Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2001-07-15

Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

Cell sensitivity to irradiation and DNA repair processes

International Nuclear Information System (INIS)

Kozubek, S.; Krasavin, E.A.

1984-01-01

A new model of oxygen effect realisation is proposed for E.coli cells. The model explains differencies in oxygen enhancement ratio (OER) between wild type cells and repair deficient mutants. These differencies are logically linked to corresponding defects in repair systems. A quantitative analysis has been performed. The dependence of OER and cell sensitivity on the properties of cultivation medium is considered, too. Decreasing OER and increasing sensitivity in poor conditions are explained as the consequence of the shift of repair capacity from slow to fast repair system

Optimizing Computation of Repairs from Active Integrity Constraints

DEFF Research Database (Denmark)

Cruz-Filipe, Luís

2014-01-01

Active integrity constraints (AICs) are a form of integrity constraints for databases that not only identify inconsistencies, but also suggest how these can be overcome. The semantics for AICs defines different types of repairs, but deciding whether an inconsistent database can be repaired...... and finding possible repairs is a NP- or Σ2p-complete problem, depending on the type of repairs one has in mind. In this paper, we introduce two different relations on AICs: an equivalence relation of independence, allowing the search to be parallelized among the equivalence classes, and a precedence relation...

Laparoscopic Inguinal Hernia Repair in a Developing Nation: Short ...

African Journals Online (AJOL)

bilateral hernias, and recurrent hernias), there are data demonstrating an ... no reports of laparoscopic inguinal hernia repair from the. Anglophone ... MATERIALS AND METHODS .... inguinal hernia repair has advantages over open repair for.

Is Conventional Open Repair for Abdominal Aortic Aneurysm Feasible in Nonagenarians?

Science.gov (United States)

Uehara, Kyokun; Matsuda, Hitoshi; Inoue, Yosuke; Omura, Atsushi; Seike, Yoshimasa; Sasaki, Hiroaki; Kobayashi, Junjiro

2017-09-25

Background : Although endovascular repair for abdominal aortic aneurysm has been found to be beneficial in very elderly patients, some patients have contraindications to this procedure. For nonagenarians, the results of open repair remain unclear. The purpose of this study was to compare the outcomes of open vs. endovascular repair for abdominal aortic aneurysm in nonagenarian patients. Methods and Results : Fourteen patients undergoing open surgical repair and 24 undergoing endovascular repair for abdominal aortic aneurysm were evaluated. There was no significant difference in early mortality between the open and endovascular groups (0% vs. 4.1%, p=0.16). The open repair group required much longer hospital stays (26.4 vs. 10.6 days, respectively, p=0.003). Finally, 12 patients (86%) undergoing open repair vs. 21 (88%) undergoing endovascular repair returned home (p=0.49). During a mean follow-up period of 23.4±23.5 months, cumulative estimated 1- and 3-year survival rates were 90.0% and 48.0%, respectively in the open repair group and 90.6% and 54.9%, respectively in the endovascular repair group (p=0.51). Conclusion : Although endovascular repair for abdominal aortic aneurysm was superior in terms of recovery, the results of conventional open repair were acceptable even in nonagenarian patients. Open repair remains an alternative for patients with contraindications to endovascular repair.

Ontology Alignment Repair through Modularization and Confidence-Based Heuristics.

Directory of Open Access Journals (Sweden)

Emanuel Santos

Full Text Available Ontology Matching aims at identifying a set of semantic correspondences, called an alignment, between related ontologies. In recent years, there has been a growing interest in efficient and effective matching methods for large ontologies. However, alignments produced for large ontologies are often logically incoherent. It was only recently that the use of repair techniques to improve the coherence of ontology alignments began to be explored. This paper presents a novel modularization technique for ontology alignment repair which extracts fragments of the input ontologies that only contain the necessary classes and relations to resolve all detectable incoherences. The paper presents also an alignment repair algorithm that uses a global repair strategy to minimize both the degree of incoherence and the number of mappings removed from the alignment, while overcoming the scalability problem by employing the proposed modularization technique. Our evaluation shows that our modularization technique produces significantly small fragments of the ontologies and that our repair algorithm produces more complete alignments than other current alignment repair systems, while obtaining an equivalent degree of incoherence. Additionally, we also present a variant of our repair algorithm that makes use of the confidence values of the mappings to improve alignment repair. Our repair algorithm was implemented as part of AgreementMakerLight, a free and open-source ontology matching system.

Ontology Alignment Repair through Modularization and Confidence-Based Heuristics.

Science.gov (United States)

Santos, Emanuel; Faria, Daniel; Pesquita, Catia; Couto, Francisco M

2015-01-01

Ontology Matching aims at identifying a set of semantic correspondences, called an alignment, between related ontologies. In recent years, there has been a growing interest in efficient and effective matching methods for large ontologies. However, alignments produced for large ontologies are often logically incoherent. It was only recently that the use of repair techniques to improve the coherence of ontology alignments began to be explored. This paper presents a novel modularization technique for ontology alignment repair which extracts fragments of the input ontologies that only contain the necessary classes and relations to resolve all detectable incoherences. The paper presents also an alignment repair algorithm that uses a global repair strategy to minimize both the degree of incoherence and the number of mappings removed from the alignment, while overcoming the scalability problem by employing the proposed modularization technique. Our evaluation shows that our modularization technique produces significantly small fragments of the ontologies and that our repair algorithm produces more complete alignments than other current alignment repair systems, while obtaining an equivalent degree of incoherence. Additionally, we also present a variant of our repair algorithm that makes use of the confidence values of the mappings to improve alignment repair. Our repair algorithm was implemented as part of AgreementMakerLight, a free and open-source ontology matching system.

Internal audit of costs on fixed assets repair

Directory of Open Access Journals (Sweden)

M.Yu. Samchyk

2016-12-01

Full Text Available The article focuses on the approaches to the process and methods of expenditure audit on repair and modernization of fixed assets and the author considers that there is no single approach to understanding the issue. The author improves the organizational and methodological support of internal audit of expenditures on the fixed assets repair and modernization that forms the accurate information for management repair and modernization of fixed assets. The paper specifies the goals and objectives of internal expenditures on repair and modernization of fixed assets, depending on the sources of such facilities to the company, allowing the author to determine the documentary control methods to be applied by an auditor to perform each task. The article determines the areas of risk components of internal control that can lead to ineffective implementation of authority by officials of an enterprise in the process of fixed assets repair, which can cause inefficient use of resources and, consequently, decrease in the efficiency of the work of fixed assets repair and modernization. The author proposes the list of auditor’s questions to assess the internal control system in the repair of fixed assets and these questions will help identify the significant drawbacks of control means.

Improved criteria for the repair of fabrication flaws

International Nuclear Information System (INIS)

Doctor, S.R.; Schuster, G.J.; Simonen, F.A.

2003-01-01

Section III of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code for nuclear power plant components requires radiographic examinations (RT) of welds and requires repairs for RT indications that exceed code acceptable sizes. This paper describes research that has generated data on welding flaws, which indicated that the largest flaws occur in repaired welds. The fabrication flaws were detected in material removed from cancelled nuclear power plants using high sensitivity Nondestructive Examination (NDE) and validated by complementary NDE and destructive testing. Evidence suggests that repairs are often for small and benign RT indications at locations buried within the vessel or pipe wall. Probabilistic fracture mechanics calculations are described in this paper to predict the increases in vessel failure probabilities caused by the repair-induced flaws. Calculations address failures of embrittled vessel welds for pressurized thermal shock (PTS) transients. In this case small flaws, which are relatively common, can cause brittle fracture, such that the rarely encountered repair flaws of large sizes gave only modestly increased failure probabilities. The paper recommends the use of more discriminating ultrasonic examinations in place of RT examinations along with repair criteria based on a fitness-for-purpose approach that minimize the number of unjustified repairs. (author)

Regulation of DNA repair by parkin

International Nuclear Information System (INIS)

Kao, Shyan-Yuan

2009-01-01

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

Chemical repair of trypsin-histidinyl radical

International Nuclear Information System (INIS)

Jovanovic, S.V.; Ruvarac, I.; Jankovic, I.; Josimovic, L.

1991-01-01

Oxyl radicals, such as hydroxyl, alkoxyl and peroxyl, react with biomolecules to produce bioradicals. Unless chemically repaired by suitable antioxidants, these bioradicals form stable products. This leads to loss of biological function of parent biomolecules with deleterious biological results, such as mutagenesis and cancer. Consequently, the understanding of the mechanisms of oxyl radical damage to biomolecules and chemical repair of such damage is crucial for the development of strategies for anticarcinogenesis and radioprotection. In this study the chemical repair of the histidinyl radical generated upon the trichloromethylperoxyl radical reaction with trypsin vas investigated by gamma radiolysis. The trypsin histidinyl radical is a resonance-stabilized heterocyclic free radical which was found to be unreactive with oxygen. The efficacy of the chemical repair of the trypsin-histidinyl radical by endogenous antioxidants which are electron donors (e.g. 5-hydroxytryptophan, uric acid) is compared to that of antioxidants which are H-atom donors (e. g. glutathione). 9 refs., 2 figs., 1 tab

46 CFR 131.575 - Yearly inspections and repair.

Science.gov (United States)

2010-10-01

... repaired as needed at least once a year. This procedure includes emptying and cleaning each fuel tank and... 46 Shipping 4 2010-10-01 2010-10-01 false Yearly inspections and repair. 131.575 Section 131.575..., Drills, and Inspections § 131.575 Yearly inspections and repair. (a) Each lifeboat, rescue boat, rigid...

Smoking increases the risk of early meniscus repair failure.

Science.gov (United States)

Blackwell, Ryan; Schmitt, Laura C; Flanigan, David C; Magnussen, Robert A

2016-05-01

The goal of this study is to determine whether patients who smoke cigarettes at the time of surgery are at significantly increased risk of early meniscus repair failure relative to non-smokers. Retrospective chart review identified 64 current smokers within a series of 444 consecutive patients who underwent meniscus repair during a 7 years period. Fifty-two of these 64 smokers were available for follow-up and were matched by age, sex, and ACL status with non-smokers from the same cohort. Records of these 104 patients with a total of 120 meniscus repairs were reviewed to identify meniscus repair failure (defined as repeat surgery on the index meniscus) during the median 13-month (range: 3-79 months) follow-up period. The smoking and non-smoking groups were similar in age, sex, ACL status, BMI, meniscus repair technique, and meniscus involved. Meniscus repair failure occurred in 19 of the 112 menisci in 104 patients, for an overall failure risk of 17 %. Of the 19 failures, 14 occurred in 79 repaired medial menisci (18 % failure risk) and 5 occurred in 33 repaired lateral menisci (15 % failure risk). Meniscus repair failure occurred in significantly more smokers (15 failures in 56 menisci in 52 patients -27 % failure risk) than non-smokers (4 failures in 56 menisci in 52 patients -7 % failure risk) (p = 0.0076). Smoking is associated with significantly increased risk of early meniscus repair failure as defined by the incidence of repeat surgery on the index meniscus. III.

Comparative long-term results of mitral valve repair in adults with chronic rheumatic disease and degenerative disease: is repair for "burnt-out" rheumatic disease still inferior to repair for degenerative disease in the current era?

Science.gov (United States)

Dillon, Jeswant; Yakub, Mohd Azhari; Kong, Pau Kiew; Ramli, Mohd Faizal; Jaffar, Norfazlina; Gaffar, Intan Fariza

2015-03-01

Mitral valve repair is perceived to be of limited durability for advanced rheumatic disease in adults. We aim to examine the long-term outcomes of repair for rheumatic disease, identify predictors of durability, and compare with repair for degenerative disease. Rheumatic and degenerative mitral valve repairs in patients aged 40 years or more were prospectively analyzed. The primary outcomes investigated were mortality, freedom from reoperation, and valve failure. Logistic regression analysis was performed to define predictors of poor outcome. Between 1997 and 2011, 253 rheumatic and 148 degenerative mitral valves were repaired. The age of patients in both groups was similar, with a mean of 54.1 ± 8.4 years versus 55.6 ± 7.3 years (P = .49). Freedom from reoperation for rheumatic valves at 5 and 10 years was 98.4%, comparable to 95.3% (P = .12) for degenerative valves. Freedom from valve failure at 5 and 10 years was 91.4% and 81.5% for rheumatic repairs and 82.5% and 75.4% for degenerative repairs, respectively (P = .15). The presence of residual mitral regurgitation greater than 2+ before discharge was the only significant independent predictor of reoperation, whereas residual mitral regurgitation greater than 2+ and leaflet procedures were significant risk factors for valve failure. The durability of rheumatic mitral valve repair in the current era has improved and is comparable to the outstanding durability of repairs for degenerative disease, even in the adult rheumatic population. Modifications of standard repair techniques, adherence to the importance of good leaflet coaptation, and strict quality control with stringent use of intraoperative transesophageal echocardiography have all contributed to the improved long-term results. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

BMCloud: Minimizing Repair Bandwidth and Maintenance Cost in Cloud Storage

Directory of Open Access Journals (Sweden)

Chao Yin

2013-01-01

Full Text Available To protect data in cloud storage, fault tolerance and efficient recovery become very important. Recent studies have developed numerous solutions based on erasure code techniques to solve this problem using functional repairs. However, there are two limitations to address. The first one is consistency since the Encoding Matrix (EM is different among clouds. The other one is repairing bandwidth, which is a concern for most of us. We addressed these two problems from both theoretical and practical perspectives. We developed BMCloud, a new low repair bandwidth, low maintenance cost cloud storage system, which aims to reduce repair bandwidth and maintenance cost. The system employs both functional repair and exact repair while it inherits advantages from the both. We propose the JUDGE_STYLE algorithm, which can judge whether the system should adopt exact repair or functional repair. We implemented a networked storage system prototype and demonstrated our findings. Compared with existing solutions, BMCloud can be used in engineering to save repair bandwidth and degrade maintenance significantly.

Optimal maintenance policies in incomplete repair models

International Nuclear Information System (INIS)

Kahle, Waltraud

2007-01-01

We consider an incomplete repair model, that is, the impact of repair is not minimal as in the homogeneous Poisson process and not 'as good as new' as in renewal processes but lies between these boundary cases. The repairs are assumed to impact the failure intensity following a virtual age process of the general form proposed by Kijima. In previous works field data from an industrial setting were used to fit several models. In most cases the estimated rate of occurrence of failures was that of an underlying exponential distribution of the time between failures. In this paper, it is shown that there exist maintenance schedules under which the failure behavior of the failure-repair process becomes a homogeneous Poisson process

An Anatomic and Biomechanical Comparison of Bankart Repair Configurations.

Science.gov (United States)

Judson, Christopher H; Voss, Andreas; Obopilwe, Elifho; Dyrna, Felix; Arciero, Robert A; Shea, Kevin P

2017-11-01

Suture anchor repair for anterior shoulder instability can be performed using a number of different repair techniques, but none has been proven superior in terms of anatomic and biomechanical properties. Purpose/Hypothesis: The purpose was to compare the anatomic footprint coverage and biomechanical characteristics of 4 different Bankart repair techniques: (1) single row with simple sutures, (2) single row with horizontal mattress sutures, (3) double row with sutures, and (4) double row with labral tape. The hypotheses were as follows: (1) double-row techniques would improve the footprint coverage and biomechanical properties compared with single-row techniques, (2) horizontal mattress sutures would increase the footprint coverage compared with simple sutures, and (3) repair techniques with labral tape and sutures would not show different biomechanical properties. Controlled laboratory study. Twenty-four fresh-frozen cadaveric specimens were dissected. The native labrum was removed and the footprint marked and measured. Repair for each of the 4 groups was performed, and the uncovered footprint was measured using a 3-dimensional digitizer. The strength of the repair sites was assessed using a servohydraulic testing machine and a digital video system to record load to failure, cyclic displacement, and stiffness. The double-row repair techniques with sutures and labral tape covered 73.4% and 77.0% of the footprint, respectively. These percentages were significantly higher than the footprint coverage achieved by single-row repair techniques using simple sutures (38.1%) and horizontal mattress sutures (32.8%) ( P row and double-row groups or between the simple suture and horizontal mattress suture techniques. Likewise, there was no difference in the biomechanical properties of the double-row repair techniques with sutures versus labral tape. Double-row repair techniques provided better coverage of the native footprint of the labrum but did not provide superior

Evaluation of outcome of totally extra peritoneal laparoscopic inguinal hernia repair with lichtenstein open repair

International Nuclear Information System (INIS)

Ahmed, I.; Dian, A.; Azam, U.F.; Khan, M.

2015-01-01

The objective of this study was to evaluate outcome of total extraperitoneal laparoscopic inguinal hernia repair with Lichtenstein open repair in terms of postoperative pain. Study Design: Quasi experimental study. Place and Duration of Study: Surgical unit l Rawalpindi and Allied hospitals from January to June 2012. Patients and Methods: Sixty patients, with unilateral, primary, inguinal hernia were alternately allocated to undergo either total extraperitoneal (TEP) laparoscopic repair of inguinal hernia or Lichtenstein tension free, mesh repair of inguinal hernia. Pain scores at 12, 24, and 48 hours and at 7 days of follow up were noted using a visual analogue scale. Total number of intravenous injections of Diclofenac Sodium requested by the patient for pain relief was also noted. Results: At 12 hours after surgery, the mean pain scores in the TEP group were 3.1 ± 1.8 and in the Lichtenstein group they were 4.2 ± 2.1 (p 0.031). At 24 hours after surgery, the scores were 2.3 ± 1.5 and 3.1 ± 1.9 for the TEP and Lichtenstein groups, respectively (p = 0.026). At 48 hours after surgery, the mean pain scores in the TEP group were 1.5 ± 1.1 while in the Lichtenstein group they were 2.0 ± 1.6 (p = 0.041). At 7 days after surgery, the scores were 0.3 ± 0.5 in the TEP group and 0.4 ± 0.8 in the Lichtenstein group (0.137). The mean number of injection of Diclofenac Sodium required by the TEP and Lichtenstein groups was 3.1 ± 1.6 and 5.8 ± 2.2, respectively (p = 0.011). Conclusion: Less postoperative pain and requirement for analgesics were reported by patients who underwent total extraperitoneal laparoscopic repair of inguinal hernia as compared to those who underwent inguinal hernia repair by Lichtenstein tension free mesh hernioplasty. (author)

Repair of U/G and U/A in DNA by UNG2-associated repair complexes takes place predominantly by short-patch repair both in proliferating and growth-arrested cells

DEFF Research Database (Denmark)

Akbari, Mansour; Otterlei, Marit; Pena Diaz, Javier

2004-01-01

Nuclear uracil-DNA glycosylase UNG2 has an established role in repair of U/A pairs resulting from misincorporation of dUMP during replication. In antigen-stimulated B-lymphocytes UNG2 removes uracil from U/G mispairs as part of somatic hypermutation and class switch recombination processes. Using......, PCNA and DNA ligase, the latter detected as activity. Short-patch repair was the predominant mechanism both in extracts and UNG2-ARC from proliferating and less BER-proficient growth-arrested cells. Repair of U/G mispairs and U/A pairs was completely inhibited by neutralizing UNG...

Umbilical Hernia Repair and Pregnancy: Before, during, after…

Directory of Open Access Journals (Sweden)

Hakan Kulacoglu

2018-01-01

Full Text Available Umbilical hernias are most common in women than men. Pregnancy may cause herniation or render a preexisting one apparent, because of progressively raised intra-abdominal pressure. The incidence of umbilical hernia among pregnancies is 0.08%. Surgical algorithm for a pregnant woman with a hernia is not thoroughly clear. There is no consensus about the timing of surgery for an umbilical hernia in a woman either who is already pregnant or planning a pregnancy. If the hernia is incarcerated or strangulated at the time of diagnosis, an emergency repair is inevitable. If the hernia is not complicated, but symptomatic an elective repair should be proposed. When the patient has a small and asymptomatic hernia it may be better to postpone the repair until she gives birth. If the hernia is repaired by suture alone, a high risk of recurrence exists during pregnancy. Umbilical hernia repair during pregnancy can be performed with minimal morbidity to the mother and baby. Second trimester is a proper timing for surgery. Asymptomatic hernias can be repaired, following childbirth or at the time of cesarean section (C-section. Elective repair after childbirth is possible as early as postpartum of eighth week. A 1-year interval can give the patient a very smooth convalescence, including hormonal stabilization and return to normal body weight. Moreover, surgery can be postponed for a longer time even after another pregnancy, if the patients would like to have more children. Diastasis recti are very frequent in pregnancy. It may persist in postpartum period. A high recurrence risk is expected in patients with rectus diastasis. This risk is especially high after suture repairs. Mesh repairs should be considered in this situation.

Training and research reactor facility longevity extension program

International Nuclear Information System (INIS)

Carriveau, G.W.

1991-01-01

Since 1943, over 550 training and research reactors have been in operation. According to statistics from the International Atomic Energy Agency, ∼325 training and research reactors are currently in service. This total includes a wide variety of designs covering a range of power and research capabilities located virtually around the world. A program has been established at General Atomics (GA) that is dedicated to the support of extended longevity of training and research reactor facilities. Aspects of this program include the following: (1) new instrumentation and control systems; (2) improved and upgraded nuclear monitoring and control channels; (3) facility testing, repair and upgrade services that include (a) pool or tank integrity, (b) cooling system, and (c) water purification system; (4) fuel element testing procedures and replacement; (5) control rod drive rebuilding and upgrades; (6) control and monitoring system calibration and repair service; (7) training services, including reactor operations, maintenance, instrumentation calibration, and repair; and (8) expanded or new uses such as neutron radiography and autoradiography, isotope production, nuclear medicine, activation analysis, and material properties modification

49 CFR 192.311 - Repair of plastic pipe.

Science.gov (United States)

2010-10-01

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

Maintenance and Repair of Concrete Structures

NARCIS (Netherlands)

Bijen, J.M.J.M.

1989-01-01

In 1987 and 1988 a series of articles was published in the Dutchjournal "Cement" about maintenance and repair of concrete structures. The series was written to promote the transfer of know-how concerning maintenance and repair of concrete structures. Use has been made of know-how developed in the

30 CFR 57.6801 - Vehicle repair.

Science.gov (United States)

2010-07-01

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

Evidence for three types of x-ray damage repair in yeast and sensitivity of totally repair deficient strains to sunlight

International Nuclear Information System (INIS)

Game, J.C.; Schild, D.; Mortimer, R.K.

1987-01-01

Mutants of yeast that confer sensitivity to x-rays are known to fall into two epistasis groups, called here the RAD51 and RAD18 groups, which are each thought to control a different type of x-ray repair. They examine here the role of genes in a third repair pathways in x-ray repair. RAD1 and RAD3 are known to be important in the repair of pyrimidine dimers after uv-irradiation. They find that these genes can also play an important role in x-ray repair, but that this role is only exposed when both the other pathways of x-ray repair are blocked. Double mutants blocked in the RAD51 and RAD18 pathways are significantly less x-ray sensitive than triple mutants blocked in these pathways but also mutant in either the RAD1 or RAD3 genes. In a related experiment, they tested the importance of DNA repair in nature by determining the sensitivity to natural unfiltered sunlight of a strain lacking all known DNA repair pathways. They constructed a quadruple mutant strain containing RAD1-1, RAD18-2, RAD51-1 and PHR1-1. The latter mutation blocks the cell's ability to photoreactivate uv damage. They found that this strain was so sensitive to sunlight that less than three seconds' exposure would cause an average of one lethal hit per cell, and survival was less than 2% after ten seconds' exposure. Wild type yeast at sea level showed no killing after thirty minutes. the quadruple mutant is approximately one thousand times more sensitive to sunlight than the related wild type

Advances in biologic augmentation for rotator cuff repair

Science.gov (United States)

Patel, Sahishnu; Gualtieri, Anthony P.; Lu, Helen H.; Levine, William N.

2016-01-01

Rotator cuff tear is a very common shoulder injury that often necessitates surgical intervention for repair. Despite advances in surgical techniques for rotator cuff repair, there is a high incidence of failure after surgery because of poor healing capacity attributed to many factors. The complexity of tendon-to-bone integration inherently presents a challenge for repair because of a large biomechanical mismatch between the tendon and bone and insufficient regeneration of native tissue, leading to the formation of fibrovascular scar tissue. Therefore, various biological augmentation approaches have been investigated to improve rotator cuff repair healing. This review highlights recent advances in three fundamental approaches for biological augmentation for functional and integrative tendon–bone repair. First, the exploration, application, and delivery of growth factors to improve regeneration of native tissue is discussed. Second, applications of stem cell and other cell-based therapies to replenish damaged tissue for better healing is covered. Finally, this review will highlight the development and applications of compatible biomaterials to both better recapitulate the tendon–bone interface and improve delivery of biological factors for enhanced integrative repair. PMID:27750374

DNA Repair and Ethnic Differences in Prostate Cancer Risk

National Research Council Canada - National Science Library

Goldman, Radoslav

2008-01-01

.... To evaluate this hypothesis we quantify DNA repair capacity in blood cells using comet assay and evaluate how this repair capacity is related to genetic variants in OGG1 and XRCC1 DNA repair genes...

DNA Repair and Ethnic Differences in Prostate Cancer Risk

National Research Council Canada - National Science Library

Goldman, Radoslav

2007-01-01

.... To evaluate this hypothesis we quantify DNA repair capacity in blood cells using comet assay and evaluate how this repair capacity is related to genetic variants in OGG1 and XRCC1 DNA repair genes...

DNA Repair and Ethnic Differences in Prostate Cancer Risk

National Research Council Canada - National Science Library

Goldman, Radoslav

2006-01-01

.... To evaluate this hypothesis, we quantify DNA repair capacity in blood cells using comet assay and evaluate how this repair capacity is related to genetic variants in OGG1 and XRCC1 DNA repair genes...

[Biomarkers of radiation-induced DNA repair processes].

Science.gov (United States)

Vallard, Alexis; Rancoule, Chloé; Guy, Jean-Baptiste; Espenel, Sophie; Sauvaigo, Sylvie; Rodriguez-Lafrasse, Claire; Magné, Nicolas

2017-11-01

The identification of DNA repair biomarkers is of paramount importance. Indeed, it is the first step in the process of modulating radiosensitivity and radioresistance. Unlike tools of detection and measurement of DNA damage, DNA repair biomarkers highlight the variations of DNA damage responses, depending on the dose and the dose rate. The aim of the present review is to describe the main biomarkers of radiation-induced DNA repair. We will focus on double strand breaks (DSB), because of their major role in radiation-induced cell death. The most important DNA repair biomarkers are DNA damage signaling proteins, with ATM, DNA-PKcs, 53BP1 and γ-H2AX. They can be analyzed either using immunostaining, or using lived cell imaging. However, to date, these techniques are still time and money consuming. The development of "omics" technologies should lead the way to new (and usable in daily routine) DNA repair biomarkers. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

Frequency of intrachromosomal homologous recombination induced by UV radiation in normally repairing and excision repair-deficient human cells

International Nuclear Information System (INIS)

Tsujimura, T.; Maher, V.M.; McCormick, J.J.; Godwin, A.R.; Liskay, R.M.

1990-01-01

To investigate the role of DNA damage and nucleotide excision repair in intrachromosomal homologous recombination, a plasmid containing duplicated copies of the gene coding for hygromycin resistance was introduced into the genome of a repair-proficient human cell line, KMST-6, and two repair-deficient lines, XP2OS(SV) from xeroderma pigmentosum complementation group A and XP2YO(SV) from complementation group F. Neither hygromycin-resistance gene codes for a functional enzyme because each contains an insertion/deletion mutation at a unique site, but recombination between the two defective genes can yield hygromycin-resistant cells. The rates of spontaneous recombination in normal and xeroderma pigmentosum cell strains containing the recombination substrate were found to be similar. The frequency of UV-induced recombination was determined for three of these cell strains. At low doses, the group A cell strain and the group F cell strain showed a significant increase in frequency of recombinants. The repair-proficient cell strain required 10-to 20-fold higher doses of UV to exhibit comparable increases in frequency of recombinants. These results suggest that unexcised DNA damage, rather than the excision repair process per se, stimulates such recombination

Plasma membrane wounding and repair in pulmonary diseases.

Science.gov (United States)

Cong, Xiaofei; Hubmayr, Rolf D; Li, Changgong; Zhao, Xiaoli

2017-03-01

Various pathophysiological conditions such as surfactant dysfunction, mechanical ventilation, inflammation, pathogen products, environmental exposures, and gastric acid aspiration stress lung cells, and the compromise of plasma membranes occurs as a result. The mechanisms necessary for cells to repair plasma membrane defects have been extensively investigated in the last two decades, and some of these key repair mechanisms are also shown to occur following lung cell injury. Because it was theorized that lung wounding and repair are involved in the pathogenesis of acute respiratory distress syndrome (ARDS) and idiopathic pulmonary fibrosis (IPF), in this review, we summarized the experimental evidence of lung cell injury in these two devastating syndromes and discuss relevant genetic, physical, and biological injury mechanisms, as well as mechanisms used by lung cells for cell survival and membrane repair. Finally, we discuss relevant signaling pathways that may be activated by chronic or repeated lung cell injury as an extension of our cell injury and repair focus in this review. We hope that a holistic view of injurious stimuli relevant for ARDS and IPF could lead to updated experimental models. In addition, parallel discussion of membrane repair mechanisms in lung cells and injury-activated signaling pathways would encourage research to bridge gaps in current knowledge. Indeed, deep understanding of lung cell wounding and repair, and discovery of relevant repair moieties for lung cells, should inspire the development of new therapies that are likely preventive and broadly effective for targeting injurious pulmonary diseases. Copyright © 2017 the American Physiological Society.

Three dimensional multi-pass repair weld simulations

International Nuclear Information System (INIS)

Elcoate, C.D.; Dennis, R.J.; Bouchard, P.J.; Smith, M.C.

2005-01-01

Full 3-dimensional (3-D) simulation of multi-pass weld repairs is now feasible and practical given the development of improved analysis tools and significantly greater computer power. This paper presents residual stress results from 3-D finite element (FE) analyses simulating a long (arc length of 62 deg. ) and a short (arc length of 20 deg. ) repair to a girth weld in a 19.6 mm thick, 432 mm outer diameter cylindrical test component. Sensitivity studies are used to illustrate the importance of weld bead inter-pass temperature assumptions and to show where model symmetry can be used to reduce the analysis size. The predicted residual stress results are compared with measured axial, hoop and radial through-wall profiles in the heat affected zone of the test component repairs. A good overall agreement is achieved between neutron diffraction and deep hole drilling measurements and the prediction at the mid-length position of the short repair. These results demonstrate that a coarse 3-D FE model, using a 'block-dumped' weld bead deposition approach (rather than progressively depositing weld metal), can accurately capture the important components of a short repair weld residual stress field. However, comparisons of measured with predicted residual stress at mid-length and stop-end positions in the long repair are less satisfactory implying some shortcomings in the FE modelling approach that warrant further investigation

Weld Repair of Thin Aluminum Sheet

Science.gov (United States)

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

1986-01-01

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

The relationship of transcription and repair of radioinduced DNA damage

International Nuclear Information System (INIS)

Zhestyanikov, V.D.; Igusheva, O.A.

1997-01-01

The data are discussed which has become a basement of such important findings as involvement of transcription into repair or existence of transcription-coupling repair factors. Thymine glycols which are appear under ionizing radiation exposure, are repaired preferentially in transcribed DNA. In present review the preferential repair of ionizing radiation-induced singlestrand breaks (SSBa) in transcribed DNA of human cells. Discontinuous distribution of DNA repair along hole genome has a grate role in biological processes

The development of a remote repair system for deep water pipelines

Energy Technology Data Exchange (ETDEWEB)

Frazer, Ian; Giles, John [Stolt Offshore MS Ltd., Aberdeen (United Kingdom)

2000-07-01

The ability to maintain a high level of flexibility within the contingency plans for sub sea pipeline repair is a critical issue normally achieved by basing the repair plans on diver intervention. This allows the pipeline operator flexibility to respond to particular repair situations as they occur, minimize up front planning and optimize the investment in repair equipment and stock. However for deep water pipelines all intervention must be performed by remote methods, which require the development of suitable equipment and more detailed repair procedures. This paper describes the development of a remotely operated pipeline repair system capable of working down to 3000 m and allowing a relatively high level of flexibility with minimum investment in repair stock. The repair system is based upon the Modular Advanced Tie-In System (MATIS) which has been successfully developed for the tie-in of deep water flow lines. The MATIS repair system is based on the use of standard flanges to replace a damaged section of pipe with a spool piece in a similar manner to a hyperbaric welded repair. Various repair scenarios are discussed in the paper together with the equipment and the procedures used to perform the repair. The paper will also discuss the other remote repair options such as hot tapping and friction stitch welding. (author)

Investigation of DNA damage and repair mechanism using deinococcus radiodurans

International Nuclear Information System (INIS)

Lau How Mooi; Kikuchi, M.; Kobayashi, Y.; Narumi, I.; Watanabe, H.

1997-01-01

Deninococcus Radiodurans, formerly known as Micrococcus Radiodurans, is a popular bacterium because of its high resistance to damage by carcinogens such as ionizing radiation (Dean et. al. 1966; Kitayama and Matsuyama 1968) and UV radiation (Gasvon et. al., 1995; Arrange et. al. 1993). In this report, we investigated the high resistance to ionizing radiation by this bacterium. The bacteria had been exposed from I to 5 kGy of gamma radiation and then incubated in TGY medium to study their ability to repair the broken DNA. The repair time was measured by Pulse Field Gel Electrophoresis (PFGE) method. The repair time for each dose was determined. Also in order to ensure that the repair was perfect, the bacterium was subjected to a second exposure of ionizing radiation after it has fully repaired. It was found that the 'second' repair characteristic was similar to the first repair. This confirmed that the repair after the exposure to the ionizing radiation was perfect

DNA repair systems as targets of cadmium toxicity

International Nuclear Information System (INIS)

Giaginis, Constantinos; Gatzidou, Elisavet; Theocharis, Stamatios

2006-01-01

Cadmium (Cd) is a heavy metal and a potent carcinogen implicated in tumor development through occupational and environmental exposure. Recent evidence suggests that proteins participating in the DNA repair systems, especially in excision and mismatch repair, are sensitive targets of Cd toxicity. Cd by interfering and inhibiting these DNA repair processes might contribute to increased risk for tumor formation in humans. In the present review, the information available on the interference of Cd with DNA repair systems and their inhibition is summarized. These actions could possibly explain the indirect contribution of Cd to mutagenic effects and/or carcinogenicity

Pure robotic retrocaval ureter repair

Directory of Open Access Journals (Sweden)

Ashok k. Hemal

2008-12-01

Full Text Available PURPOSE: To demonstrate the feasibility of pure robotic retrocaval ureter repair. MATERIALS AND METHODS: A 33 year old female presented with right loin pain and obstruction on intravenous urography with the classical "fish-hook" appearance. She was counseled on the various methods of repair and elected to have a robot assisted repair. The following steps are performed during a pure robotic retrocaval ureter repair. The patient is placed in a modified flank position, pneumoperitoneum created and ports inserted. The colon is mobilized to expose the retroperitoneal structures: inferior vena cava, right gonadal vein, right ureter, and duodenum. The renal pelvis and ureter are mobilized and the renal pelvis transected. The ureter is transposed anterior to the inferior vena cava and a pyelopyelostomy is performed over a JJ stent. RESULTS: This patient was discharged on postoperative day 3. The catheter and drain tube were removed on day 1. Her JJ stent was removed at 6 weeks postoperatively. The postoperative intravenous urography at 3 months confirmed normal drainage of contrast medium. CONCLUSION: Pure robotic retrocaval ureter is a feasible procedure; however, there does not appear to be any great advantage over pure laparoscopy, apart from the ergonomic ease for the surgeon as well the simpler intracorporeal suturing.

Repair of damaged DNA in vivo: Final technical report

International Nuclear Information System (INIS)

Hanawalt, P.C.

1987-09-01

This contract was initiated in 1962 with the US Atomic Energy Commission to carry out basic research on the effects of radiation on the process of DNA replication in bacteria. Within the first contract year we discovered repair replication at the same time that Setlow and Carrier discovered pyrimidine dimer excision. These discoveries led to the elucidation of the process of excision-repair, one of the most important mechanisms by which living systems, including humans, respond to structural damage in their genetic material. We improved methodology for distinguishing repair replication from semiconservative replication and instructed others in these techniques. Painter then was the first to demonstrate repair replication in ultraviolet irradiated human cells. He, in turn, instructed James Cleaver who discovered that skin fibroblasts from patients with xeroderma pigmentosum were defective in excision-repair. People with this genetic defect are extremely sensitive to sunlight and they develop carcinomas and melanomas of the skin with high frequency. The existence of this hereditary disease attests to the importance of DNA repair in man. We certainly could not survive in the normal ultraviolet flux from the sun if our DNA were not continuously monitored for damage and repaired. Other hereditary diseases such as ataxia telangiectasia, Cockayne's syndrome, Blooms syndrome and Fanconi's anemia also involve deficiencies in DNA damage processing. The field of DNA repair has developed rapidly as we have learned that most environmental chemical carcinogens as well as radiation produce repairable damage in DNA. 251 refs

75 FR 16552 - High-Speed Intercity Passenger Rail (HSIPR) Program

Science.gov (United States)

2010-04-01

...; Enhancing intercity travel options; Ensuring a state of good repair of key intercity passenger rail assets... DEPARTMENT OF TRANSPORTATION Federal Railroad Administration High-Speed Intercity Passenger Rail... selections for the High-Speed Intercity Passenger Rail (HSIPR) Program. This notice builds on the program...

Use of duraseal in repair of cerebrospinal fluid leaks.

Science.gov (United States)

Chin, Christopher J; Kus, Lukas; Rotenberg, Brian W

2010-10-01

The purpose of our article is to review the use of the DuraSeal Sealant System (Confluent Surgical Inc., Waltham, MA) in the repair of complex cerebrospinal fluid (CSF) leaks in endoscopic skull-base surgery. Retrospective chart review. London Health Sciences Centre. A database of endoscopic skull-base cases between 2007 and 2009 that involved CSF leakage repaired with DuraSeal was created. Demographic data and operative reports were collected and analyzed qualitatively. Recurrence of CSF leak after repair. Five cases were identified that met study criteria. In four of the five cases, the repair was successful. There were no complications related to DuraSeal use. Comparison to a subset of patients using Tisseel Fibrin Sealant (Baxter, Toronto, ON) for repair did not show a significant difference in failure rate (χ2 = 0.029, p = .858). There are a variety of techniques described to repair CSF rhinorrhea, with various studies demonstrating the advantages of using tissue glues in CSF leak repairs. We used DuraSeal in five patients to enhance graft strength and form a watertight seal. The system was effective in the majority of patients. Our study is the first to report on endoscopic endonasal repair of CSF leaks using DuraSeal.

Three-dimensional echocardiographic assessment of the repaired mitral valve.

Science.gov (United States)

Maslow, Andrew; Mahmood, Feroze; Poppas, Athena; Singh, Arun

2014-02-01

This study examined the geometric changes of the mitral valve (MV) after repair using conventional and three-dimensional echocardiography. Prospective evaluation of consecutive patients undergoing mitral valve repair. Tertiary care university hospital. Fifty consecutive patients scheduled for elective repair of the mitral valve for regurgitant disease. Intraoperative transesophageal echocardiography. Assessments of valve area (MVA) were performed using two-dimensional planimetry (2D-Plan), pressure half-time (PHT), and three-dimensional planimetry (3D-Plan). In addition, the direction of ventricular inflow was assessed from the three-dimensional imaging. Good correlations (r = 0.83) and agreement (-0.08 +/- 0.43 cm(2)) were seen between the MVA measured with 3D-Plan and PHT, and were better than either compared to 2D-Plan. MVAs were smaller after repair of functional disease repaired with an annuloplasty ring. After repair, ventricular inflow was directed toward the lateral ventricular wall. Subgroup analysis showed that the change in inflow angle was not different after repair of functional disease (168 to 171 degrees) as compared to those presenting with degenerative disease (168 to 148 degrees; p<0.0001). Three-dimensional imaging provides caregivers with a unique ability to assess changes in valve function after mitral valve repair. Copyright © 2014 Elsevier Inc. All rights reserved.

Parametric study on patch repaired CFRP laminates using FEA

Energy Technology Data Exchange (ETDEWEB)

Kashfuddoja, M.; Ramji, M. [Indian Institute of Technology. Engineering Optics Lab. Dept. of Mechanical Engineering, Hyderabad (India)

2012-07-01

Carbon fibre reinforced plastic (CFRP) composite laminates have become popular for structural applications as they are lighter, stronger and tougher. Composite structures are also susceptible to damage while in service. For improved service life, the damage needs to be repaired so that repair structure integrity is enhanced. Various parameters like patch size and shape, it's layup sequence and adhesive thickness would influence the performance of the repaired structure. In present work, a parametric study is carried out using finite element analysis (FEA) to investigate the influence of various parameters involved in composite repair. The panel is made of carbon / epoxy composite laminate with stacking sequence of (0/{+-}45/900)s and is subjected to tensile load. Damaged CFRP laminates is repaired by symmetrical patch adhesively bonded over the damaged area. Circular patch of different stacking sequence and size is considered. Influence of adhesive material and it's thickness on repair efficiency is also investigated. The influence of various repair parameters on peel stress is also analysed. (Author)

Fatigue behaviour study on repaired aramid fiber/epoxy composites

Directory of Open Access Journals (Sweden)

Edson Cocchieri Botelho

2009-06-01

Full Text Available Aramid fiber reinforced polymer composites have been used in a wide variety of applications, such as aerospace, marine, sporting equipment and in the defense sector, due to their outstanding properties at low density. The most widely adopted procedure to investigate the repair of composites has been by repairing damages simulated in composite specimens. This work presents the structural repair influence on tensile and fatigue properties of a typical aramid fiber/epoxy composite used in the aerospace industry. According to this work, the aramid/epoxy composites with and without repair present tensile strength values of 618 and 680MPa, respectively, and tensile modulus of 26.5 and 30.1 GPa, respectively. Therefore, the fatigue results show that in loads higher than 170 MPa, both composites present a low life cycle (lower than 200,000 cycles and the repaired aramid/epoxy composite presented low fatigue resistance in low and high cycle when compared with non-repaired composite. With these results, it is possible to observe a decrease of the measured mechanical properties of the repaired composites.

Artificial-Crack-Behavior Test Evaluation of the Water-Leakage Repair Materials Used for the Repair of Water-Leakage Cracks in Concrete Structures

OpenAIRE

Soo-Yeon Kim; Sang-Keun Oh; Byoungil Kim

2016-01-01

There are no existing standard test methods at home and abroad that can verify the performance of water leakage repair materials, and it is thus very difficult to perform quality control checks in the field of water leakage repair. This study determined that the key factors that have the greatest impact on the water leakage repair materials are the micro-behaviors of cracks, and proposed an artificial-crack-behavior test method for the performance verification of the repair materials. The per...

The effect of double-row fixation on initial repair strength in rotator cuff repair: a biomechanical study.

Science.gov (United States)

Meier, Steven W; Meier, Jeffrey D

2006-11-01

The purpose of this study was to compare the initial mechanical strength of 3 rotator cuff repair techniques. A total of 30 fresh-frozen cadaveric shoulders were prepared, and full-thickness supraspinatus tears were created. Specimens were randomized and placed into 3 groups: (1) transosseous suture technique (group I: TOS, n = 10, 6F/4M), (2) single-row suture anchor fixation (group II: SRSA, n = 10, 6F/4M), and (3) double-row suture anchor fixation (group III: DRSA, n = 10, 6F/4M). Each specimen underwent cyclic load testing from 5 N to 180 N at a rate of 33 mm/sec. The test was stopped when complete failure (repair site gap of 10 mm) or a total of 5,000 cycles was attained. Group I (TOS) failed at an average of 75.3 +/- 22.49 cycles, and group II (SRSA) at an average of 798.3 +/- 73.28 cycles; group III (DRSA) had no failures because all samples were stopped when 5,000 cycles had been completed. Fixation strength of the DRSA technique proved to be significantly greater than that of SRSA (P row suture anchor fixation was significantly stronger than was single-row repair. Therefore, double-row fixation may be superior to other techniques in that it provides a substantially stronger repair that could lead to improved biologic healing. A high incidence of incomplete healing occurs in rotator cuff repair. Use of double-row fixation may help the clinician to address some deficiencies in current methods by increasing the strength of the repair, potentially leading to improved healing rates.

Repair/maintenance design for tokamak experimental fusion reactor

International Nuclear Information System (INIS)

1978-10-01

Repair and maintenance design for JXFR has been studied. The reactor is in eight modules so that a damaged module alone can be separated from the other modules and transferred from the reactor room to a repair shop. Design work covers overhaul procedure, dismounting equipments (overhead cranes, auto welder/cutter and remote handling equipments), transport system of a module (module mounting carriages and rotating carriage), repair equipment for blanket, earthquake-proof analysis of the reactor, reactor room structure, repair shop layout, management of radioactive wastes, time and the number of persons required for overhaul etc. Though the repair and maintenance system is almost complete, there still remain problems for further study in joints of blanket cooling piping, auto welder/cutter and earthquake-proof strength in reactor disassemblage. More detailed studies and R and D are necessary for engineering perfection. (author)

Outreach Materials for the Collision Repair Campaign

Science.gov (United States)

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

76 FR 25704 - Announcement of Funding Awards for the Emergency Capital Repair Grant Program; Fiscal Year 2010

Science.gov (United States)

2011-05-05

.... Four Freedoms House of Seattle.. Four Freedoms House of Seattle WA 302 431,113 Replace the brick canopy...,114 Repair the elevators and replace the windows, cooling chassis units in the through-wall... Castle......... PA 128 294,265 Replace the roof and grinder pump. Sandpiper Run National Church Ft. Myers...

Prognostic factors in sensory recovery after digital nerve repair

OpenAIRE

Bulut, Tugrul; Akgun, Ulas; Citlak, Atilla; Aslan, Cihan; Sener, Ufuk; Sener, Muhittin

2018-01-01

Objective: The prognostic factors that affect sensory nerve recovery after digital nerve repair are variable because of nonhomogeneous data, subjective tests, and different assessment/scoring methods. The aim of this study was to evaluate the success of sensory nerve recovery after digital nerve repair and to investigate the prognostic factors in sensorial healing.Methods: Ninety-six digital nerve repairs of 63 patients were retrospectively evaluated. All nerves were repaired with end-to-end ...

Repair of UV-damaged incoming plasmid DNA in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Keszenman-Pereyra, David

1990-01-01

A whole-cell transformation assay was used for the repair of UV-damaged plasma DNA in highly-transformable haploid strains of Saccharomyces cerevisiae having different repair capabilities. The experiments described demonstrate that three epistasis groups (Friedberg 1988) are involved in the repair of UV-incoming DNA and that the repair processes act less efficiently on incoming DNA than they do on chromosomal DNA. The implications of these findings for UV repair in Saccharomyces cerevisiae are discussed. (author)

Dependence of u.v.-induced DNA excision repair on deoxyribonucleoside triphosphate concentrations in permeable human fibroblasts: a model for the inhibition of repair by hydroxyurea

International Nuclear Information System (INIS)

Hunting, D.J.; Dresler, S.L.

1985-01-01

We have tested the hypothesis that the inhibition by hydroxyurea of repair patch ligation and chromatin rearrangement during u.v.-induced DNA excision repair results from a reduction in cellular deoxyribonucleotide concentrations and not from a direct effect of hydroxyurea on the repair process. Using permeable human fibroblasts, we have shown that hydroxyurea has no direct effect on either repair synthesis or repair patch ligation. We also have shown that by reducing the deoxyribonucleoside triphosphate concentrations in the permeable cell reaction mixture, we can mimic the inhibition of repair patch ligation and chromatin rearrangement seen when u.v.-damaged intact confluent fibroblasts are treated with hydroxyurea. Our results are consistent with the concept that hydroxyurea inhibits DNA repair in intact cells by inhibiting deoxyribonucleotide synthesis through its effect on ribonucleotide reductase and, conversely, that continued deoxyribonucleotide synthesis is required for the excision repair of u.v.-induced DNA damage even in resting cells

Is laparoscopic inguinal hernia repair more effective than open repair

International Nuclear Information System (INIS)

Aly, O.; Green, A.; Joy, M.; Wong, C.H.; Malik, M

2011-01-01

To systematically review randomized controlled trials, (RCT) evidence comparing Lichtenstein to total extraperitoneal (TEP) hernia repair in terms of clinical and cost effectiveness. Study Design: Case series. Place and Duration of Study: The study was conducted at University of Abderdeen, U.K. Methodology: A comprehensive online literature search was undertaken using databases such as MEDLINE, PubMed, EMBASE and Springerlink. Studies were then short listed according to the selection criteria (RCT with over 100 subject and English language publications from 1995 onwards) and appraised using the SIGN Methodology Checklist. A meta analysis of the data was also performed using RevMan software. Results: Analysis of reported data shows that TEP has less postoperative pain and return to work than Lichtenstein method. Operation time is shown to be longer in the TEP but this difference is shortened with increasing surgeon experience. The meta-analysis of the data on complications shows that there are no significant differences between the two types of procedures. TEP causes more short-term recurrences which are attributed to the learning curve effect. Long term recurrence rates on the other hand show no significant differences. At present TEP is slightly more expensive than Lichtenstein repair. Conclusion: Both TEP and Lichtenstein repair are clinically effective procedures. The choice between them should be made on a case-by-case basis; which depends on the patient's preference and characteristics such as age, work and health status. (author)

A comparison of the DNA and chromosome repair kinetics after #betta# irradiation

International Nuclear Information System (INIS)

Hittelman, W.N.; Pollard, M.

1982-01-01

The kinetics of repair at the chromosome and DNA levels were compared after #betta# irradiation of Chinese hamster ovary cells (CHO). Induction and repair of DNA damage were measured by the alkaline and neutral elution techniques, while chromosome damage and repair were determined by the technique of premature chromosome condensation. During and after #betta# irradiation, significant DNA repair occurred within 2 min. This fast repair could be inhibited by EDTA and pyrophosphate and probably reflected polynucleotide ligase activity. A slower component of DNA repair was detected between 15 and 60 min after irradiation, by which time most of the DNA had been repaired. In contrast, chromosome repair was not detectable until 45 min after irradiation, and nearly half of the chromatid breaks were repaired by 60 min. Cycloheximide, an inhibitor of protein synthesis, prevented chromosome break repair, yet had no effect on the immediate formation of chromatid exchanges or DNA repair. These results suggest the following: (1) the rapidly repairing DNA lesions are not important in the repair of chromosomes; (2) chromosome damage involves only a minority of the DNA lesions measured by alkaline and neutral DNA elution; and (3) chromosome repair may involve more than simply the repair of damaged DNA that can be detected by the alkaline and neutral elution assays

Laparoscopic Repair of Inguinal Hernias

OpenAIRE

Carter, Jonathan; Duh, Quan-Yang

2011-01-01

For patients with recurrent inguinal hernia, or bilateral inguinal hernia, or for women, laparoscopic repair offers significant advantages over open techniques with regard to recurrence risk, pain, and recovery. For unilateral first-time hernias, either laparoscopic or open repair with mesh can offer excellent results. The major drawback of laparoscopy is that the technique requires a significant number of cases to master. For surgeons in group practice, it makes sense to have one surgeon in ...

Repair Types, Procedures - Part 1

Science.gov (United States)

2010-05-01

Affordable Combat Aircraft, AGARD - CP -600, 1997. [17] Helbling J, Grover R and Ratwani M. M “Analysis and Structural Test of Composite Reinforcement to...considered suitable for the composite patch repair of aluminum structure. Ductile adhesives such as FM- 73 are preferred over brittle adhesives Repair Types...zone. A proper cure cycle is followed as prescribed by the adhesive manufacturer. For FM- 73 adhesive cure at 2500F (1210C) for 120 minutes is

Initial Development of Composite Repair Resins With Low Hazardous Air Pollutant Contents

National Research Council Canada - National Science Library

LaScala, John J; Bingham, Scott; Andrews, Kevin S; Sands, James M; Palmese, Guiseppe R

2008-01-01

Unsaturated polyester-based repair resins, such a Bondo, are widely used for automotive repair, marine repair, sporting equipment repair, and household repair of metal, composites, plastics, and wood...

Early sensory re-education of the hand after peripheral nerve repair based on mirror therapy: a randomized controlled trial

Science.gov (United States)

Paula, Mayara H.; Barbosa, Rafael I.; Marcolino, Alexandre M.; Elui, Valéria M. C.; Rosén, Birgitta; Fonseca, Marisa C. R.

2016-01-01

BACKGROUND: Mirror therapy has been used as an alternative stimulus to feed the somatosensory cortex in an attempt to preserve hand cortical representation with better functional results. OBJECTIVE: To analyze the short-term functional outcome of an early re-education program using mirror therapy compared to a late classic sensory program for hand nerve repair. METHOD: This is a randomized controlled trial. We assessed 20 patients with median and ulnar nerve and flexor tendon repair using the Rosen Score combined with the DASH questionnaire. The early phase group using mirror therapy began on the first postoperative week and lasted 5 months. The control group received classic sensory re-education when the protective sensation threshold was restored. All participants received a patient education booklet and were submitted to the modified Duran protocol for flexor tendon repair. The assessments were performed by the same investigator blinded to the allocated treatment. Mann-Whitney Test and Effect Size using Cohen's d score were used for inter-group comparisons at 3 and 6 months after intervention. RESULTS: The primary outcome (Rosen score) values for the Mirror Therapy group and classic therapy control group after 3 and 6 months were 1.68 (SD=0.5); 1.96 (SD=0.56) and 1.65 (SD=0.52); 1.51 (SD=0.62), respectively. No between-group differences were observed. CONCLUSION: Although some clinical improvement was observed, mirror therapy was not shown to be more effective than late sensory re-education in an intermediate phase of nerve repair in the hand. Replication is needed to confirm these findings. PMID:26786080

Early sensory re-education of the hand after peripheral nerve repair based on mirror therapy: a randomized controlled trial

Directory of Open Access Journals (Sweden)

Mayara H. Paula

2016-02-01

Full Text Available BACKGROUND: Mirror therapy has been used as an alternative stimulus to feed the somatosensory cortex in an attempt to preserve hand cortical representation with better functional results. OBJECTIVE: To analyze the short-term functional outcome of an early re-education program using mirror therapy compared to a late classic sensory program for hand nerve repair. METHOD: This is a randomized controlled trial. We assessed 20 patients with median and ulnar nerve and flexor tendon repair using the Rosen Score combined with the DASH questionnaire. The early phase group using mirror therapy began on the first postoperative week and lasted 5 months. The control group received classic sensory re-education when the protective sensation threshold was restored. All participants received a patient education booklet and were submitted to the modified Duran protocol for flexor tendon repair. The assessments were performed by the same investigator blinded to the allocated treatment. Mann-Whitney Test and Effect Size using Cohen's d score were used for inter-group comparisons at 3 and 6 months after intervention. RESULTS: The primary outcome (Rosen score values for the Mirror Therapy group and classic therapy control group after 3 and 6 months were 1.68 (SD=0.5; 1.96 (SD=0.56 and 1.65 (SD=0.52; 1.51 (SD=0.62, respectively. No between-group differences were observed. CONCLUSION: Although some clinical improvement was observed, mirror therapy was not shown to be more effective than late sensory re-education in an intermediate phase of nerve repair in the hand. Replication is needed to confirm these findings.

Biological radiolesions and repair

International Nuclear Information System (INIS)

Laskowski, W.

1981-01-01

In 7 chapters, the book answers the following questions: 1) What reactions are induced in biological matter by absorption of radiation energy. 2) In what parts of the cell do the radiation-induced reactions with detectable biological effects occur. 3) In which way are these cell components changed by different qualities of radiation. 4) What are the cell mechanisms by which radiation-induced changes can be repaired. 5) What is the importance of these repair processes for man, his life and evolution. At the end of each chapter, there is a bibliography of relevant publications in this field. (orig./MG) [de

Outcomes of fenestrated and branched endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms.

Science.gov (United States)

Schanzer, Andres; Simons, Jessica P; Flahive, Julie; Durgin, Jonathan; Aiello, Francesco A; Doucet, Danielle; Steppacher, Robert; Messina, Louis M

2017-09-01

More than 80% of infrarenal aortic aneurysms are treated by endovascular repair. However, adoption of fenestrated and branched endovascular repair for complex aortic aneurysms has been limited, despite high morbidity and mortality associated with open repair. There are few published reports of consecutive outcomes, inclusive of all fenestrated and branched endovascular repairs, starting from the inception of a complex aortic aneurysm program. Therefore, we examined a single center's consecutive experience of fenestrated and branched endovascular repair of complex aortic aneurysms. This is a single-center, prospective, observational cohort study evaluating 30-day and 1-year outcomes in all consecutive patients who underwent fenestrated and branched endovascular repair of complex aortic aneurysms (definition: requiring one or more fenestrations or branches). Data were collected prospectively through an Institutional Review Board-approved registry and a physician-sponsored investigational device exemption clinical trial (G130210). We performed 100 consecutive complex endovascular aortic aneurysm repairs (November 2010 to March 2016) using 58 (58%) commercially manufactured custom-made devices and 42 (42%) physician-modified devices to treat 4 (4%) common iliac, 42 (42%) juxtarenal, 18 (18%) pararenal, and 36 (36%) thoracoabdominal aneurysms (type I, n = 1; type II, n = 4; type III, n = 12; type IV, n = 18; arch, n = 1). The repairs included 309 fenestrations, branches, and scallops (average of 3.1 branch arteries/case). All patients had 30-day follow-up for 30-day event rates: three (3%) deaths; six (6%) target artery occlusions; five (5%) progressions to dialysis; eight (8%) access complications; one (1%) paraparesis; one (1%) bowel ischemia; and no instances of myocardial infarction, paralysis, or stroke. Of 10 type I or type III endoleaks, 8 resolved (7 with secondary intervention, 1 without intervention). Mean follow-up time was 563 days (interquartile range

Inhibition of DNA-double strand break repair by antimony compounds

International Nuclear Information System (INIS)

Takahashi, Sentaro; Sato, Hiroshi; Kubota, Yoshihisa; Utsumi, Hiroshi; Bedford, Joel S.; Okayasu, Ryuichi

2002-01-01

DNA double strand breaks (DSBs), induced by γ-irradiation in Chinese hamster ovary cells, were used to examine whether antimony compounds affect the repair of DNA damage. The cells were first incubated with antimony trichloride or antimony potassium tartrate (both Sb(III)) for 2 h, and then irradiated with γ-rays at a dose of 40 Gy. The DNA DSB was quantified with pulsed field gel electrophoresis immediately after irradiation (non-repair group) as well as at 30 min post-irradiation (repair group). The degree of repair inhibition was determined by the differences in the amount of DNA DSB between non-repair and repair groups. Both antimony compounds inhibited repair of DNA DSB in a dose dependent manner. In trichloride, 0.2 mM antimony significantly inhibited the rejoining of DSB, while 0.4 mM was necessary in potassium antimony tartrate. The mean lethal doses, D 0 , for the treatment with antimony trichloride and antimony potassium tartrate, were approximately 0.21 and 0.12 mM, respectively. This indicates that the repair inhibition by antimony trichloride occurred in the dose range near D 0 , but the antimony potassium tartrate inhibited the repair at doses where most cells lost their proliferating ability. This is the first report to indicate that antimony compounds may inhibit the repair of radiation-induced DNA DSB

Biomechanical comparison of single-row arthroscopic rotator cuff repair technique versus transosseous repair technique.

Science.gov (United States)

Tocci, Stephen L; Tashjian, Robert Z; Leventhal, Evan; Spenciner, David B; Green, Andrew; Fleming, Braden C

2008-01-01

This study determined the effect of tear size on gap formation of single-row simple-suture arthroscopic rotator cuff repair (ARCR) vs transosseous Mason-Allen suture open RCR (ORCR) in 13 pairs of human cadaveric shoulders. A massive tear was created in 6 pairs and a large tear in 7. Repairs were cyclically tested in low-load and high-load conditions, with no significant difference in gap formation. Under low-load, gapping was greater in massive tears. Under high-load, there was a trend toward increased gap with ARCR for large tears. All repairs of massive tears failed in high-load. Gapping was greater posteriorly in massive tears for both techniques. Gap formation of a modeled RCR depends upon the tear size. ARCR of larger tears may have higher failure rates than ORCR, and the posterior aspect appears to be the site of maximum gapping. Specific attention should be directed toward maximizing initial fixation of larger rotator cuff tears, especially at the posterior aspect.

Early postoperative repair status after rotator cuff repair cannot be accurately classified using questionnaires of patient function and isokinetic strength evaluation.

Science.gov (United States)

Colliver, Jessica; Wang, Allan; Joss, Brendan; Ebert, Jay; Koh, Eamon; Breidahl, William; Ackland, Timothy

2016-04-01

This study investigated if patients with an intact tendon repair or partial-thickness retear early after rotator cuff repair display differences in clinical evaluations and whether early tendon healing can be predicted using these assessments. We prospectively evaluated 60 patients at 16 weeks after arthroscopic supraspinatus repair. Evaluation included the Oxford Shoulder Score, 11-item version of the Disabilities of the Arm, Shoulder and Hand, visual analog scale for pain, 12-item Short Form Health Survey, isokinetic strength, and magnetic resonance imaging (MRI). Independent t tests investigated clinical differences in patients based on the Sugaya MRI rotator cuff classification system (grades 1, 2, or 3). Discriminant analysis determined whether intact repairs (Sugaya grade 1) and partial-thickness retears (Sugaya grades 2 and 3) could be predicted. No differences (P repair was intact. The ability to discriminate between groups was enhanced with up to 5 variables entered; however, only 87% of the partial-retear group and 36% of the intact-repair group were correctly classified. No differences in clinical scores existed between patients stratified by the Sugaya MRI classification system at 16 weeks. An intact repair or partial-thickness retear could not be accurately predicted. Our results suggest that correct classification of healing in the early postoperative stages should involve imaging. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

26 CFR 1.162-4 - Repairs.

Science.gov (United States)

2010-04-01

... the cost of acquisition or production or the gain or loss basis of the taxpayer's plant, equipment, or other property, as the case may be, is not increased by the amount of such expenditures. Repairs in the... incidental repairs which neither materially add to the value of the property nor appreciably prolong its life...

Aspects of DNA repair and nucleotide pool imbalance

Energy Technology Data Exchange (ETDEWEB)

Holliday, R.

1985-01-01

Evidence that optimum repair depends on adequate pools of deoxynucleotide triphosphates (dNTPs) comes from the study of pyrimidine auxotrophs of Ustilago maydis. These strains are sensitive to UV light and X-rays, and for pyr1-1 it has been shown that the intracellular concentration of dTTP is reduced about 7-fold. The survival curve of pyr1-1 after UV-treatment, and split dose experiments with wild-type cells, provide evidence for an inducible repair mechanism, which probably depends on genetic recombination. Although inducible repair saves cellular resources, it has the disadvantage of becoming ineffective at doses which are high enough to inactivate the repressed structural gene(s) for repair enzymes. It is clear that a wide variety of repair mechanisms have evolved to remove lesions which arise either spontaneously or as a result of damage from external agents. Nevertheless, it would be incorrect to assume that all species require all possible pathways of repair. It is now well established that the accuracy of DNA and protein synthesis depends on proof-reading or editing mechanisms. Optimum accuracy levels will evolve from the balance between error avoidance in macromolecular synthesis and physiological efficiency in growth and propagation.

Repair of abasic sites in DNA

Energy Technology Data Exchange (ETDEWEB)

Dianov, Grigory L.; Sleeth, Kate M.; Dianova, Irina I.; Allinson, Sarah L

2003-10-29

Repair of both normal and reduced AP sites is activated by AP endonuclease, which recognizes and cleaves a phosphodiester bond 5' to the AP site. For a short period of time an incised AP site is occupied by poly(ADP-ribose) polymerase and then DNA polymerase {beta} adds one nucleotide into the repair gap and simultaneously removes the 5'-sugar phosphate. Finally, the DNA ligase III/XRCC1 complex accomplishes repair by sealing disrupted DNA ends. However, long-patch BER pathway, which is involved in the removal of reduced abasic sites, requires further DNA synthesis resulting in strand displacement and the generation of a damage-containing flap that is later removed by the flap endonuclease. Strand-displacement DNA synthesis is accomplished by DNA polymerase {delta}/{epsilon} and DNA ligase I restores DNA integrity. DNA synthesis by DNA polymerase {delta}/{epsilon} is dependent on proliferating cell nuclear antigen, which also stimulates the DNA ligase I and flap endonuclease. These repair events are supported by multiple protein-protein interactions.

Weightbearing Versus Nonweightbearing After Meniscus Repair.

Science.gov (United States)

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

2015-01-01

Optimal rehabilitation after meniscal repair remains controversial. To review the current literature on weightbearing status after meniscal repairs and to provide evidence-based recommendations for postoperative rehabilitation. MEDLINE (January 1, 1993 to July 1, 2014) and Embase (January 1, 1993 to July 1, 2014) were queried with use of the terms meniscus OR/AND repair AND rehabilitation. Included studies were those with levels of evidence 1 through 4, with minimum 2 years follow-up and in an English publication. Systematic review. Level 4. Demographics and clinical and radiographic outcomes of meniscus repair at a minimum of 2 years follow-up were extracted. Successful clinical outcomes ranged from 70% to 94% with conservative rehabilitation. More recent studies using an accelerated rehabilitation protocol with full weightbearing and early range of motion reported 64% to 96% good results. Outcomes after both conservative (restricted weightbearing) protocols and accelerated rehabilitation (immediate weightbearing) yielded similar good to excellent results; however, lack of similar objective criteria and consistency among surgical techniques and existing studies makes direct comparison difficult. © 2015 The Author(s).