• Title/Summary/Keyword: well integrity

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Sperm chromatin and DNA integrity, methyltransferase mRNA levels, and global DNA methylation in oligoasthenoteratozoospermia

  • Rahiminia, Tahereh;Yazd, Ehsan Farashahi;Fesahat, Farzaneh;Moein, Mohammad Reza;Mirjalili, Ali Mohammad;Talebi, Ali Reza
    • Clinical and Experimental Reproductive Medicine
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    • v.45 no.1
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    • pp.17-24
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    • 2018
  • Objective: To investigate sperm chromatin/DNA integrity, global DNA methylation, and DNMT mRNA transcription in men with oligoasthenoteratozoospermia (OAT) compared with normozoospermic men. Methods: Semen samples from 32 OAT patients who comprised the case group and 32 normozoospermic men who comprised the control group were isolated and purified using a standard gradient isolation procedure according to World Health Organization criteria. DNMT1, DNMT3A, and DNMT3B transcripts were then compared between groups using real-time quantitative reverse-transcription polymerase chain reaction. Global DNA methylation in sperm was determined by an enzyme-linked immunosorbent assay. Protamine deficiency and the proportion of apoptotic spermatozoa were evaluated using chromomycin A3 (CMA3), aniline blue (AB), and toluidine blue (TB) staining, as well as the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The p-values < 0.05 were considered to indicate statistical significance. Results: Significantly higher proportions of AB+, TB+, CMA3+, and TUNEL+ spermatozoa, as well as DNMT3A and DNMT3B transcription, were found in the OAT group. Positive correlations were detected between sperm parameters, DNA/chromatin damage, and DNMT3A and DNMT3B transcripts. Global DNA methylation was significantly higher in the OAT patients and had a significant correlation with abnormal results of all sperm chromatin integrity tests, but was not associated with DNMT1, DNMT3A, or DNMT3B expression. Conclusion: Oligoasthenoteratozoospermic men showed abnormal sperm parameters, abnormal chromatin/DNA integrity, and a higher global DNA methylation rate, as well as overexpression of DNMT mRNA.

Effects of Social Support, Abuse on the Ego-Integrity in the Elderly (노인이 지각한 사회적 지지, 학대가 자아통합감에 미치는 영향)

  • Kim, Soon Yi;Lee, Jung In
    • 한국노년학
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    • v.29 no.1
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    • pp.231-242
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    • 2009
  • Purpose: The purpose of this study was to examine the effects of social support, abuse on the ego-integrity in the elderly. Method: This is a descriptive survey study. Data were collected from March to June, 2008 with 306 older adults living at home. The questionnaires consisted of social support, abuse, and ego-integrity. Result: The average score of the subjects for social support was 4.5, for abuse 1.16, and for ego-integrity 2.91. There were positive correlations between social support and ego-integrity. The negative correlations were shown between social support and abuse, as well as between ego-integrity and abuse. The correlations were statistically significant. The social support and abuse were a significant predictor of ego-integrity. Conclusion: A program for improving social support and preventing abuse should be developed. In addition nursing intervention should be provided based on the developed program for this population.

REVIEW OF SPENT FUEL INTEGRITY EVALUATION FOR DRY STORAGE

  • Kook, Donghak;Choi, Jongwon;Kim, Juseong;Kim, Yongsoo
    • Nuclear Engineering and Technology
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    • v.45 no.1
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    • pp.115-124
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    • 2013
  • Among the several options to solve PWR spent fuel accumulation problem in Korea, the dry storage method could be the most realistic and applicable solution in the near future. As the basic objectives of dry storage are to prevent a gross rupture of spent fuel during operation and to keep its retrievability until transportation, at the same time the importance of a spent fuel integrity evaluation that can estimate its condition at the final stage of dry storage is very high. According to the national need and technology progress, two representative nations of spent fuel dry storage, the USA and Japan, have established different system temperature criteria, which is the only controllable factor in a dry storage system. However, there are no technical criteria for this evaluation in Korea yet, it is necessary to review the previously well-organized methodologies of advanced countries and to set up our own domestic evaluation direction due to the nation's need for dry storage. To satisfy this necessity, building a domestic spent fuel test database should be the first step. Based on those data, it is highly recommended to compare domestic data range with foreign results, to build our own criteria, and to expand on evaluation work into recently issued integrity problems by using a comprehensive integrity evaluation code.

An Overview of Seabed Storage Methods for Pipelines and Other Oil and Gas Equipment

  • Fatah, M.C.;Mills, A.;Darwin, A.;Selman, C.
    • Corrosion Science and Technology
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    • v.16 no.2
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    • pp.76-84
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    • 2017
  • In the construction of subsea oil and gas developments, it is increasingly common that subsea oil and gas equipment will be installed in subsea well before final hookup and production. Installation of wellheads, subsea hardware, pipelines, and surface facilities (platforms, FPSO, FLNG, connected terminals, or gas plants) are increasingly driven by independent cost and vessel availability schedules; this gives rise to requirements that the subsea facilities must be stored in the seabed for a specific time. In addition, schedule delays, particularly in the installation or startup of the connected platform, FPSO, FLNG, or onshore plant may cause unexpected extensions of the intended storage period. Currently, there are two methods commonly used for storage subsea facilities in the seabed: dry parking and wet parking. Each method has its own risks, challenges, and implications for the facility life and its integrity. The corrosion management and preservation method selection is a crucial factor to be considered in choosing the appropriate storage method and achieving a successful seabed storage. An overview of those factors is presented, along with a discussion on the internal corrosion threats and assessments.

Reliability-Based Capacity Rating of High-Speed Rail-Road Bridges (신뢰성에 기초한 고속철도 교량의 내하력평가)

  • 조효남;이승재
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1995.04a
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    • pp.73-81
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    • 1995
  • In Korea, the pilot construction of the first high-speed railroad on the Seoul-Pusan has already started 2 years ago. In the thesis, an attempt is made to develop reliability-based integrity-assessment models for the computer-aided control and maintenance of high-speed railroad bridges. The strength limit state models for PC railroad bridges encompass the bending and shear strengths as well as the strength interaction equations which simultaneously take into the element and system reliablities of the proposed limit states and reliability models. Then, the actual load carrying capacity and the realistic safety of bridges are evaluated using the system reliability-based equivalent strength, and the results are compared with those of the element reliability-based or conventional methods. Various parametric studies are performed for the proposed reliability-based safety and integrity-assessment models using the actual PC box girder bridges used in the pilot construction. And the sensitivity analyses are performed for the basic random variables included in strength limit state models. It is concluded that proposed models may be practically applied for the rational assessment of safety and integrity of high speed railroad bridges.

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Backward Propagation of User-Defined Integrity Constraints On Active Object-Oriented Database (능동적 객체지향 데이타베이스에서 사용자 정의 제약조건의 역방향 전달에 관한 연구)

  • 도남철;최인준
    • The Journal of Information Technology and Database
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    • v.1 no.1
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    • pp.63-81
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    • 1994
  • The trigger mechanism in active object-oriented database systems is known to be a good tool for describing user-defined integrity constraints. It cannot adequately support, however, certain integrity constrains specified on the objects in class composition hierarchy. Those are the cases where the constraints must be maintained in the forward direction along the composition hierarchy as well as in the backward direction We call theses kinds of problems "backward propagation problem" and investigate several ways to resolve them using the currently available techniques. Based on them, a new constructor, called CONSTRAIN $T^{cch}$, is proposed. The constructor can be realized with enhanced facilities for active OODBMS which we recommend in this paper.d facilities for active OODBMS which we recommend in this paper.r.

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Integrity Evaluation Model for a Straight Pipe with Local Wall Thinning Defect (직관 배관의 국부 감육결함에 대한 건전성 평가 모델)

  • Park Chi Yong;Kim Jin Weon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.5 s.236
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    • pp.734-742
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    • 2005
  • The present study proposes the integrity evaluation model for a straight pipe with local wall thinning defect, which reflects the characteristics of training shape and loading condition in the Piping of nuclear power plant. For this purpose, a series of finite element analyses are performed under various defect geometries and loading conditions, and real pipe experiment data performed previously is employed. The model includes the effect of thinning length as well as thinning depth and width, and also it considers the combined loading effect between internal pressure and bending moment. The proposed model has been validated using the results of finite element analysis and pipe experiment data. The results indicate that the proposed model provides more reliable predictions of pipe failure than the current existing model, in terms of accuracy, consistency, and conservativeness of results.

Provably-Secure Public Auditing with Deduplication

  • Kim, Dongmin;Jeong, Ik Rae
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.4
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    • pp.2219-2236
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    • 2017
  • With cloud storage services, users can handle an enormous amount of data in an efficient manner. However, due to the widespread popularization of cloud storage, users have raised concerns about the integrity of outsourced data, since they no longer possess the data locally. To address these concerns, many auditing schemes have been proposed that allow users to check the integrity of their outsourced data without retrieving it in full. Yuan and Yu proposed a public auditing scheme with a deduplication property where the cloud server does not store the duplicated data between users. In this paper, we analyze the weakness of the Yuan and Yu's scheme as well as present modifications which could improve the security of the scheme. We also define two types of adversaries and prove that our proposed scheme is secure against these adversaries under formal security models.

A Study on Surface Integrity in Ground Layers (연삭 가공면의 표면성상에 관한 연구)

  • Kim, Gyung-Nyun;Cheong, Chae-Cheon;Cha, Il-Nam
    • Journal of the Korean Society for Precision Engineering
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    • v.8 no.4
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    • pp.64-75
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    • 1991
  • The design of structures of modern industry has developed to satisfy stringent service, realiability and safety. Up to now, geometric profile which means surface foughness and dimension accuracy is mainly treated in manufacturing process of work surface. But it is inevitable to evaluate changes of surface geometry as well as the nature of alterations in surface layers because surface of workpiece changes as a result of phase transformation, chemical changes, plastic deformation and stress changes. This paper is to present principal data for safety design by verifying the effect of grinding conditions and method in grinding layers and to explain the method of measuring surface integrity. In this paper, structural steel(SM20C) is used as a workpiece. Of integrity, surface roughness in view of surface texture is analyzed by frequency domain and residual stress, structures and defect of ground layers in view of surface metallurgy are investigated.

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Integrity evaluations of bogie frame using ultrasonic-fractography analysis (초음파-파면해석에 의한 대차 프레임의 건전성 평가)

  • 윤인식;권성태;정우현;박덕신;김경국
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.461-467
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    • 2000
  • This study proposes the integrity evaluation of bogie frame using ultrasonic waves-fractography analysis. Analysis objectives in this study are to investigate fracture planes of damaged zone by the A-scan method. The surface condition of fracture plane shows degree of degradation by stress concentration. The detection of the natural defects in bogie frame is performed using the characteristics of echodynamic pattern in ultrasonic signal. Results of ultrasonic testing agree fairly well with those of actual fracture plane. In quantitative fractography analysis, microstructures of actual fracture plane turned out to be intergranular and transgranular fracture, Proposed ultrasonic-fractography analysis in this study can be used for the integrity evaluation of the bogie frame

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