• Title/Summary/Keyword: Deletion

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Multi-level Optimization for Orthotropic Steel Deck Bridges (강바닥판교의 다단계 최적설계)

  • Cho, Hyo-Nam;Chung, Jee-Sung;Min, Daee-Hong;Lee, Kwang-Min
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.04b
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    • pp.439-448
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    • 2000
  • A multi-level design synthesis (MLDA) algorithm for efficiently optimizing orthotropic steel deck bridges is proposed in the paper, because it is usually very difficult to optimize orthotropic steel deck bridges using a conventional single-level (CSL) algorithn since the bridges have a large number of members and show complex structural behaviors. In the proposed MLDS algorithms a coordination method is introduced to divide the bridges into main girders and orthotropic steel decks and decomposition method is also used to reduce the number of design variables of the decks for system level optimization. For efficient optimization of the bridges the MLDS algorithm incorporates the crucial approximation techliques such as constraints deletion and stress reanalysis. The constraint deletion technique for deflection is found to be very useful for the optimization problem of the bridges, since a deflection constraint is usually inactive in the design. Considering the complex system of the bridges, the proposed the efficient stress reanalysis technique may prove to be a very effective method, since it does not require expensive design sensitivity analyses. The applicability and robustness of the MLDS algorithm is demonstrated using various numerical examples and compared with other algorithm presently available so far.

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Optimization of Reinforced Concrete Piers Based on Efficient Reanalysis Technique (효율적인 재해석 기법에 의한 철근콘크리트 교각의 최적설계)

  • 조효남;민대홍;신만규
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.14 no.4
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    • pp.505-513
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    • 2001
  • In this study, an optimum design algorithm using efficient reanalysis is proposed for seismic design of Reinforced Concrete (RC) piers. The proposed algorithm for optimization of RC piers is based on efficient reanalysis technique. Considering structural behavior of RC piers, the other approximation technique such as artificial constraint deletion is introduced to increase the efficiency of optimization. The efficiency and robustness of the proposed algorithm including the proposed reanalysis technique is demonstrated by comparing it with a conventional optimization algorithm. A few of design examples are optimized to show the applicability of the proposed algorithm.

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Insertion/deletion (I/D) in the Angiotensin-converting Enzyme Gene and Breast Cancer Risk: Lack of Association in a Meta-analysis

  • Pei, Xin-Hong;Li, Hui-Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5633-5636
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    • 2012
  • Purpose: Breast cancer is an important cause of cancer-related death in women. Numerous studies have evaluated the association between the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene and breast cancer risk. However, the specific association is still controversial rather than conclusive. Therefore, we performed a meta-analysis of related studies to address this controversy. Methods: PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association between the I/D polymorphism in the ACE gene and susceptibility to breast cancer. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Results: 10 separate studies of 7 included articles with 10,888 subjects on the relation between the I/D polymorphism in the ACE gene and breast cancer were analyzed by meta-analysis, and our results showed no association between the I/D polymorphism in the ACE gene and breast cancer in total population and different populations. No publication bias was found in the present study. Conclusions: The ACE I/D polymorphism may not be associated with breast cancer risk. Further large and well-designed studies are needed to confirm this conclusion.

Lack of Association Between GSTM1 and GSTT1 Polymorphisms and Brain Tumour Risk

  • Sima, Xiu-Tian;Zhong, Wei-Ying;Liu, Jian-Gang;You, Chao
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.1
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    • pp.325-328
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    • 2012
  • Objective: Glutathione S-transferases (GSTs) are important enzymes that are involved in detoxification of environmental carcinogens. Molecular epidemiological studies have been conducted to investigate the association between GSTM1 and GSTT1 homozygous deletion polymorphisms and brain tumours but results have been conflicting. The aim of this study was to clarify this problem using a meta-analysis. Methods: A total of 9 records were identified by searching the PubMed and Embase databases. Fixed- and random-effects models were performed to estimate the pooled odds ratios. Results: No significant association was found between the GSTM1 and GSTT1 homozygous deletion polymorphisms and risk of brain tumours, including glioma and meningioma. Similar negative results were also observed in both population-based and hospital-based studies. Conclusion: These findings indicate that the GSTM1 and GSTT1 polymorphisms may not be related to the development of brain tumours.

Forkhead Genes are Key Regulators of Developmental Processes in Aspergillus nidulans

  • Oh, Dong-Soon;Kim, Jong-Hwa;Han, Dong-Min;Han, Kap-Hoon
    • 한국균학회소식:학술대회논문집
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    • 2014.05a
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    • pp.39-39
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    • 2014
  • In a homothallic filamentous fungus Aspergillus nidulans, sexual and asexual developments are largely affected by the genetic and environmental factors. To regulate the complex subsets of genes involved in the developmental processes accurately, tight regulations of transcription factors are required. The forkhead type transcription factors are the class of regulators that function in a broad spectrum of cellular and developmental processes in many species from yeast to human. Here, we identified the fkhA and fkhB genes that encode a conserved forkhead transcription factors. The fkhA deletion resulted in the complete loss of fruiting body formation under all conditions favoring sexual development, suggesting that the fkhA gene is required for sexual development in A. nidulans. Overexpression of fkhA resulted in enhanced formation of fruiting bodies under induction condition not only in the normal condition but also in the condition of presence of 0.6 M KCl, which strongly inhibits sexual development. To know the function of the fkhB gene, we also generated fkhB knock-out strain in A. nidulans. Deletion of fkhB resulted in abnormal conidiophore formation under standard conditions and delayed sexual development process, suggesting that the fkhB gene plays an important role in conidiophore morphogenesis Taken together, these results suggest that the fkhA gene is necessary and sufficient for regulating sexual development and the fkhB gene is a transcription factor related in asexual developmental process in A. nidulans.

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The Studies on the Statistical Reliability and Significancy of the Questionnaire for the Sasang Constitution (사상체질판별(四象體質判別) 검사지(檢査紙) 문항(問項)의 타당성(妥當性)과 신뢰성(信賴性) 및 응답자(應答者) 개체분석(應答者)에 관한 연구(硏究))

  • Lee, Hwa-Seop;An, Taek-Won
    • Journal of Haehwa Medicine
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    • v.12 no.2
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    • pp.177-197
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    • 2004
  • 1. The values of Cronbach's alpha for the Taeyang, Taeum, Soyang and Soeum questionnaire were 0.7955, 0.7776, 0.8545, and 0.8601 respectively. These results indicate a highly satisfactory level of internal consistency for the questionnaire. 2. If the deletion of an item increases Cronbach's alpha then what that means is that the deletion of that item improves reliability. Therefore, any items that result in substantially greater values of alpha than the overall alpha may need to be deleted from the questionnaire to improve its reliability. 3. Factor analysis was performed on the 81 questionnaires. Based on the scree plot and the number and decrement of eigen values greater than one, three to four factor solution was most significant. 4. The hierarchical cluster analysis was performed on the 81 Sasang constitution questionnaire. These results suggested that two or four clusters identified with homogeneous groups 5. The hierarchical cluster analysis was performed on the 1046 responders. These results suggested that two, three, or four clusters might identified with homogeneous groups. Furthemore, there were statistically significant difference among the each group by ANOVA(P<0.0001).

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