• Title/Summary/Keyword: Negative Selection

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Studies on Search for Varieties of Higher Sulfur Containing Protein with Lower Lipoxygenase Activity and Their Inheritance and Selection Efficiency for Breeding of Good Quality Soybean Cultivar 2. Variation of Lipoxygenase Activity and its Inheritance with Selection Efficiency (양질대두 품종 육성을 위한 고함황 단백질 및 lipoxygenase 저활성도 품종의 탐색과 그의 유전 및 선발효과 2. Lipoxygenase 저활성도 품종의 탐색과 그 유전 및 선발효과 연구)

  • 이홍석;박의호;구자환
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.2
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    • pp.180-186
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    • 1994
  • Lipoxygenase activity of soybean seeds of approximately 507 genotypes as well as its inheritance and selection efficiency in early breeding generation was measured in the Department of Agronomy, Seoul National University to facilitate breeding for low lipoxygenase activity of soybean. Average seed lipoxygenase activity of 507 cultivars and strains was 350 unit (unit: $\Delta$0.01 /min. /mg at 234nm) and ranged from 50 to 670 unit. There was no difference in mean lipoxygenase activity according to apparent seed characters such as seed coat and embryo color. But early mature soybean genotypes had fairly low lipoxygenase activity. Lipoxygenase activity was inherited quantitatively, in which additive effect was greater than dominant one and proportion of gene with positive effects was similar to that with negative ones. Estimated narrow- and broad-sense heritabilities were 0.78 and 0.86 for lipoxygenase activity, respectively. Heritability measured from selection in early breeding lines for high or low lipoxygenase activity was 64~76% or 54~62%, respectively. And selection for high lipoxygenase activity increased by 29.7~44.7%, whereas that for low ones decreased by 21.8~27.3%, respectively, when compared to random population. Clear effect in selecting of lipoxygenase activity was present in early generation.

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Genetic Trends for Laying Traits in the Brown Tsaiya (Anas platyrhynchos) Selected with Restricted Genetic Selection Index

  • Chen, D.T.;Lee, S.R.;Hu, Y.H.;Huang, C.C.;Cheng, Y.S.;Tai, C.;Poivey, J.P.;Rouvier, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.12
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    • pp.1705-1710
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    • 2003
  • A small body size of Brown Tsaiya laying duck is desirable to reduce maintenance requirements, so the body weight at 40 weeks of age (BW40) has to be maintained at its current level. Egg weight has to be maintained at around 65 g to meet market requirements. Eggshell strength at 40 weeks of age (ES40) must to be increased in order to maintain a low incidence of broken eggs. Thus, number of eggs laid up to 52 weeks of age (EN52) has to be increased without negative correlated response on ES40. A new linear genetic selection index was used: $I_g=a_0{\times}GEW40\;(g)+a_1{\times}GBW40\;(g)+a_2{\times}GES40\;(kg/cm^2)+a_3{\times}GEN52\;(eggs)$ where GEW40, GBW40, GES40 and GEN52 were the multitrait best linear unbiased prediction (MT-BLUP) animal model predictors of the breeding values respectively of egg weight and body weight at 40 weeks of age (EW40, BW40), ES40 and EN52. The coefficients $a_0$, $a_1$, $a_2$ and $a_3$ were calculated with constraints of 0.0 g, 0.0 g and $0.013kg/cm^2$ for expected genetic gains in EW40, BW40 and ES40 respectively and maximum gain in EN52. Since 1997, the drakes and the ducks were selected according to their own indexes, with this new genetic selection index. From G0 to G4, the average per generation predicted genetic responses in female duck were +0.05 g for EW40, +0.92 g for BW40, $+0.035kg/cm^2$ for ES40 and +2.13 eggs for EN52. Which represented respectively 0.07%, 0.06%, 0.67% and 1.0% of the means of the EW40, BW40, ES40 and EN52. For ES40 and EN52, it represented also respectively 16.1% and 21.6% of the additive genetic standard deviation of these traits. Thevse results indicated that selection of laying Brown Tsaiya by a restricted genetic selection index and with MT-BLUP animal model could be an efficient tool for improving the efficiency of egg production, increasing egg shell strength and egg number while holding egg weight and body weight constants.

Establishment of a Selection System for the Site-Specific Incorporation of Unnatural Amino Acids into Protein (비천연 아미노산의 위치특이적 단백질 삽입을 위한 Amino Acyl-tRNA Synthetase 선별시스템 개발)

  • Edan, Dawood Salim;Choi, Inkyung;Park, Jungchan
    • Korean Journal of Microbiology
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    • v.50 no.1
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    • pp.1-7
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    • 2014
  • Site-specific incorporation of unnatural amino acids (SSIUA) into protein can be achieved in vivo by coexpression of an orthogonal pair of suppressor tRNA and engineered aminoacyl-tRNA synthetase (ARS) that specifically ligates an unnatural amino acid to the suppressor tRNA. As a step to develop the SSIUA technique in Escherichia coli, here we established a new 2-step screening system that can be used for selecting an ARS variant(s) that ligates an unnatural amino acid to a suppressor tRNA. A positive selection system consists of chloramphenicol acetyl transferase gene containing an amber mutation at the $27^{th}$ residue, and efficiently concentrated amber suppressible ARS with a maximum enrichment factor of $9.0{\times}10^5$. On the other hand, a negative selection system was constructed by adding multiple amber codons in front of a lethal gene encoding the control of cell death B toxin (ccdB) which acts as an inhibitory protein of bacterial topoisomerase II. Amber suppression of ccdB by an orthogonal pair of Saccharomyces cerevisiae tyrosyl-tRNA synthetase (TyrRS) and an amber suppressor tRNA significantly inhibits bacterial growth. This selection system was also able to efficiently remove amber suppressible ARS which could ligate natural amino acids to the suppressor tRNA. Thus, sequential combination of these two selection systems might be able to function as a powerful tool for selecting an ARS variant that specifically ligates an unnatural amino acid to the suppressor tRNA from an ARS mutant pool.

Perception on Impact of Climate Change on Forest Ecosystem in Protected Area of West Bengal, India

  • Dey, Tanusri;Pala, Nazir A.;Shukla, Gopal;Pal, Prabhat K.;Chakravarty, Sumit
    • Journal of Forest and Environmental Science
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    • v.33 no.1
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    • pp.1-7
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    • 2017
  • In the present exploration we identified perception of forest dependent communities in relation to impact of climate change on forest ecosystem in and around Chilapatta reserve forest in northern part of West Bengal, India. Purposive sampling method was used for selection of area and random sampling method was used for selection of respondent. The data collection in this study was through questionnaire based personal in-depth interviews. Almost all the respondents (94%) were farmers and rest had occupation other than farming. Almost all the respondents perceived negative impact of climate change on forest though the level of perception varies from very low to medium (0.23-0.52) based on average perception score after assigning score to individual statements. The level of perception on impact of climate change on forest ecology and forest flora of the community is low and very low as the average perception score is 0.39 and 0.23, respectively while, it is medium (0.52) for forest fauna. Alternately their perception on decreased stream/river flow and quick drying of seasonal streams or water bodies is based on their livelihood experience as they depend on these for their domestic and irrigation water use and fish catch for family diet.

A novel classification approach based on Naïve Bayes for Twitter sentiment analysis

  • Song, Junseok;Kim, Kyung Tae;Lee, Byungjun;Kim, Sangyoung;Youn, Hee Yong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.6
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    • pp.2996-3011
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    • 2017
  • With rapid growth of web technology and dissemination of smart devices, social networking service(SNS) is widely used. As a result, huge amount of data are generated from SNS such as Twitter, and sentiment analysis of SNS data is very important for various applications and services. In the existing sentiment analysis based on the $Na{\ddot{i}}ve$ Bayes algorithm, a same number of attributes is usually employed to estimate the weight of each class. Moreover, uncountable and meaningless attributes are included. This results in decreased accuracy of sentiment analysis. In this paper two methods are proposed to resolve these issues, which reflect the difference of the number of positive words and negative words in calculating the weights, and eliminate insignificant words in the feature selection step using Multinomial $Na{\ddot{i}}ve$ Bayes(MNB) algorithm. Performance comparison demonstrates that the proposed scheme significantly increases the accuracy compared to the existing Multivariate Bernoulli $Na{\ddot{i}}ve$ Bayes(BNB) algorithm and MNB scheme.

Seismic Influence on Subsea Pipeline Stresses

  • Choi, Byoung-Yeol;Lee, Sang-Gil;Kim, Jin-Kwang;Oh, Jin-Soo
    • Journal of Advanced Research in Ocean Engineering
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    • v.3 no.1
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    • pp.1-14
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    • 2017
  • The safety analysis of an earthquake is carried out during the operation of a subsea pipeline and an onshore pipeline. Several cases are proposed for consideration. In the case of a buried pipeline, permanent ground deformation by the earthquake and an increase of internal pressure by the acceleration of the earthquake should be considered. In the case of a subsea pipeline, a bending moment is caused by liquefaction of the backfill material on a trenched seabed, etc., which results in a high bending moment of the buried pipeline. The bending moment causes the collapse of the subsea pipeline or a leak of crude oil or gas, which results in economic loss due to enormous environmental contamination and social economic loss owing to operation functional failure. Thus, in order to prevent economic loss and operation loss, structurally sensitive design with regard to seismic characteristics must be performed in the buried pipeline in advance, and the negative impact on the buried pipeline must be minimized by conducting a thorough analysis on the seabed and backfilling material selection. Moreover, it is proposed to consider the selection of material properties for the buried pipeline. A more economical review is also required for detailed study.

The Analysis on the Relationship between Household Debts and Married Women's Labor Supply (가계부채와 기혼여성 노동공급의 관계 분석)

  • Song, Heonjae;Shin, Woori
    • Journal of Labour Economics
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    • v.40 no.1
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    • pp.37-68
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    • 2017
  • This study analyzes the relationship between household debts and married female's labor supply. For doing this we construct effective interest rate faced by each household using interest paid amount and household financial debt amount. The effective interests rate for the households which have no financial debt are estimated by Heckman Selection model. The estimation results show that the increase in effective interest rate has led to the expansion of married women's the labor market participation. This suggests a possibility that negative scenarios resulting from an increase in interest rate can be partially offset by an increase in household labor supply and a rise in labor income.

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The Selection and Assessment system of Manufacturer in the Home Shopping Industry (홈쇼핑 업종에서의 협력업체 선정과 평가체계)

  • Mun, je-ok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.4
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    • pp.147-155
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    • 2015
  • Home Shopping companies haven't have any possible means of product quality control process in spite of the fact that they are selling average 16,000 different kinds of product every month. Under this condition, increases of return and product liability can have a strong negative influence on customers' trust in a home shopping brand and intentional repurchase through the same home shopping channel. To solve the problems, we applied adjusted selection and assessment system of manufacturers in home shopping industry, and the consequence of system effect was verified that there is a decrease of 10.3% in the number of returns and a decrease of 11.7% in the number of product liability.

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PSE (pale, soft, exudative) Pork : The Causes and Solutions - Review -

  • Lee, Y.B.;Choi, Y.I.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.2
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    • pp.244-252
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    • 1999
  • Intensive selection for muscle development and against fat deposition in pigs during the last 50 years has contributed to the increased incidence of porcine stress syndrome (PSS) and pale soft exudative pork (PSE). Genetics, nutrition and management, preslaughter animal handling, stunning, dehairing and carcass chilling influence the incidence and magnitude of the PSE condition. The normal incidence of PSE has been reported to range from 10 to 30%, but in some isolated instances is up to 60%. The elimination of halothane-positive pigs in breeding programs has reduced PSS and PSE. Further improvements in meat quality by terminal sire evaluation and selection can be achieved within halothane-negative populations because around 20% of the variation in meat color and water binding capacity seems to be genetically related. Pre-slaughter handling on the farm, during transit to the packing plant and at the packing plant can greatly influence the meat quality, contributing 10 to 25% of the variation. An effective stunning method, skinning instead of scalding/dehairing and rapid post-slaughter chilling further reduce the incidence of PSE pork. In addition to proper care and handling a carcass-merit based marketing system, that reflected the value differential between desirable and undesirable meat quality in the pricing system for pigs, would provide a great incentive to change pork production systems in order to improve meat quality, thus improving the image and usefulness of pork as food.

The Effect of Counterfactual Thinking on Post-purchase Behavior of Retail Management

  • Kim, Young-Ei;Yang, Hoe-Chang
    • Journal of Distribution Science
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    • v.16 no.2
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    • pp.25-33
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    • 2018
  • Purpose - This study focused on the effect of counter-factual thinking on post-purchase behavior producing consumer regret at HMR selection and purchase. We have analyzed the factors that HMR production and distribution businesses should consider because distribution and marketing strategy reflecting consumers' demand. Research design, data, and methodology - For the purpose of carrying out this research, we conducted a direst structured questionnaire to students at 'J' college. A total of 237 valid questionnaires were collected for students and their parents at 'J' university. For the hypothesis test, exploratory factor analysis, t-test, regression and structure equation path analysis were performed. Results - The consumers who often resented HMR purchase did counter-factual thinking on post-purchase behavior were likely to do switching purchases. Counter-factual thinking on post-purchase behavior had a negative influence upon consumer's satisfaction with HMR safety and marketing characteristics. Conclusions - Consumers who had been satisfied to a certain degree might have cognitive dissonance of minor mistakes of HMR product were likely to have downward counter-factual thinking through contrast effects. Therefore, HMR producer and distribution businesses that had production, distribution and marketing strategy to satisfy consumers by raw material, freshness and safety were likely to switch to another product at one time mistake of selection, purchase and use.