• Title/Summary/Keyword: Causal association

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Labor Market Participation Effects of the Earned Income Tax Credit in Korea (근로장려세제가 노동시장 참여에 미치는 효과)

  • Park, Jihye;Lee, Jungmin
    • Journal of Labour Economics
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    • v.41 no.3
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    • pp.1-59
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    • 2018
  • The Earned Income Tax Credit (EITC) is a policy that supports low-income households financially as well as provides an economic incentive to participate in the labor market. Thus, estimating the causal effect of the policy on the labor force participation rate of low-income households is critical for the policy evaluation. In this paper, we exploit the variation in the eligibility to the EITC and the size of the benefit over several reforms of the EITC in South Korea since 2008 and estimate the impact on the participation in the labor market. Using data from four major household surveys, we find that the results are mixed; in some samples and specifications, we find that the effect is positive and statistically significant, while it is insignificant in others. The estimated effect is more likely to be positive and significant when we restrict the sample to the period before 2014. It is an important topic of future research whether the EITC's effect gets weaker because it is extended to cover the self-employed and beneficiaries of the National Basic Livelihood Security.

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Genome re-sequencing to identify single nucleotide polymorphism markers for muscle color traits in broiler chickens

  • Kong, H.R.;Anthony, N.B.;Rowland, K.C.;Khatri, B.;Kong, B.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.13-18
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    • 2018
  • Objective: Meat quality including muscle color in chickens is an important trait and continuous selective pressures for fast growth and high yield have negatively impacted this trait. This study was conducted to investigate genetic variations responsible for regulating muscle color. Methods: Whole genome re-sequencing analysis using Illumina HiSeq paired end read method was performed with pooled DNA samples isolated from two broiler chicken lines divergently selected for muscle color (high muscle color [HMC] and low muscle color [LMC]) along with their random bred control line (RAN). Sequencing read data was aligned to the chicken reference genome sequence for Red Jungle Fowl (Galgal4) using reference based genome alignment with NGen program of the Lasergene software package. The potential causal single nucleotide polymorphisms (SNPs) showing non-synonymous changes in coding DNA sequence regions were chosen in each line. Bioinformatic analyses to interpret functions of genes retaining SNPs were performed using the ingenuity pathways analysis (IPA). Results: Millions of SNPs were identified and totally 2,884 SNPs (1,307 for HMC and 1,577 for LMC) showing >75% SNP rates could induce non-synonymous mutations in amino acid sequences. Of those, SNPs showing over 10 read depths yielded 15 more reliable SNPs including 1 for HMC and 14 for LMC. The IPA analyses suggested that meat color in chickens appeared to be associated with chromosomal DNA stability, the functions of ubiquitylation (UBC) and quality and quantity of various subtypes of collagens. Conclusion: In this study, various potential genetic markers showing amino acid changes were identified in differential meat color lines, that can be used for further animal selection strategy.

Effective Leadership in Public Organizations: The Impact of Organizational Structure in Asian Countries

  • Valero, Jesus N.
    • Journal of Contemporary Eastern Asia
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    • v.14 no.2
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    • pp.69-79
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    • 2015
  • Among public organizations, does variation in organizational structure explain variation in public managers' leadership styles (e.g., transformational and transactional leadership)? The study of leadership in public organizations is increasingly an area of scholarly interest partly sparked by movements to reform public organizations, particularly in the context of emergency management. There is, for example, a need for effective leadership that can help organizations respond to disasters (Kapucu et al. 2010; Van Wart and Kapucu 2011; Stern 2013). There are numerous documented cases where the lack of leadership skills has been linked to major social and economic losses as a result of poor disaster response (e.g., Hurricane Katrina in the U.S.). Yet, leadership is a complex concept and numerous theoretical frameworks have been developed to help explain it (Van Wart 2005). Practically speaking, the existence of different theories of leadership suggests that public managers can decide to exercise various styles of leadership. The style of leadership that a public manager exhibits matters because some styles are perceived to be more effective than others (Trottier et al. 2008). While the effects of leadership have been extensively studied, antecedents or predictors of leadership style have received little scholarly attention (Wright and Pandey 2009; Nielsen and Cleal 2011). The purpose of this research note then is to explore the potential causal relationship between the structure of an organization and the ability of a public manager to exercise transformational leadership in the context of emergency management in two Asian countries: South Korea and Japan. This research note consists of three main sections. The following section explores the relationship between leadership and organizational structure. The second section examines how certain concepts of leadership and organizational structure were applied in two case studies of disaster response. The final section presents some directions for future research.

Collaborative Consumption Motivation Factor Model under the Sharing Economy (공유경제 모형에서의 협력적 소비 영향요인)

  • Roh, Tae-Hyup;Choi, Hwa-Yeol
    • The Journal of Information Systems
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    • v.27 no.2
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    • pp.197-219
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    • 2018
  • Purpose The purpose of this study is to examine what motivates users to adopt one of the emerging applications for collaborative consumption of sharing economy. Using the self-determination theory, motivation theory and TAM(Technology Acceptance Model) as the theoretical framework, this study illustrates important factors that influence adoption of collaborative consumption service. We develops the ICTs(Information and Communications Technologies) initiatives and motivation model to collaborative consumption. Design/methodology/approach This paper makes use of a quantitative methodology using survey questionnaire that allows for the measurement of the eight constructs(System Availability, Contents Quality, Design & Personalization, Security & Privacy, Emotional & Social Value, Economic Value, Attitude, Adoption & Consumption) contained in the hypothesized theoretical model on the basis of the prior literatures. Data collected from a sample of 227 respondents who have used the collaborative consumption services and provided the foundation for the examination of the proposed relationships in the model. Findings This study has the following implications for the users and providers of CC platforms and services. The ICTs initiatives (System Availability, Contents Quality, Design & Personalization, Security & Privacy) are the influential factors that motivate the emotional and social value to CC. On the other hand, The ICTs initiatives (System Availability, Contents Quality) are not very significant factors of economic value to CC. The empirical analysis result indicate that there are significant causal effect among emotional & social value, economic value, and adoption to CC. This study provides important theoretical implications for innovation adoption research through an empirical examination of the relationship between ICTs initiatives, motivation factors to collaborative consumption in the sharing economy.

Analysis of extended haplotype in Korean cattle (Hanwoo) population

  • Lim, Dajeong;Choi, Bong Hwan;Cho, Yong Min;Chai, Han Ha;Jang, Gul Won;Gondro, Cedric;Jeoung, Yeoung Ho;Lee, Seung Hwan
    • BMB Reports
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    • v.49 no.9
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    • pp.514-519
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    • 2016
  • Korean cattle (Hanwoo) are categorized into three breeds based on color: brown, brindle, and black. Among these breeds, brown Hanwoo has been subjected to intensive selection to improve meat traits. To identify genetic traces driven by recent selection in brown Hanwoo, we scanned the genomes of brown and brindle Hanwoo using a bovine SNP chip. We identified 17 candidate selection signatures in brown Hanwoo and sequenced four candidate regions from 10 individuals each of brown and brindle Hanwoo. In particular, non-synonymous SNPs in the ADSL gene (K88M, L189H, and R302Q) might have had mutational effects on protein structure as a result of altering the purine pathway during nucleotide breakdown. The ADSL gene was previously reported to affect meat quality and yield in livestock. Meat quality and yield are main breeding goals for brown Hanwoo, and our results support a potential causal influence of non-synonymous SNPs in the ADSL gene.

The Effect of Media Richness, Social Presence, and Life Satisfaction on Continuance Usage Intention or Withdrawal Intention of SNS Users via Relative Deprivation (매체 풍요도, 사회적 존재감 및 생활 만족도가 상대적 박탈감을 통해 SNS 이용자의 이용 지속 의도 또는 이탈 의도에 미치는 영향)

  • Lee, Un-Kon
    • Journal of Distribution Science
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    • v.14 no.10
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    • pp.165-178
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    • 2016
  • Purpose - This study aims to empirically verify the impact of media richness, social presence, and prior life satisfaction on various continual usage or withdrawal behaviors of SNS users via both a positive path of satisfaction and a negative path of relative deprivation. By identifying these causal paths, we observe dynamic interactions of SNS user psychology in a balanced view, and provide some implications about design principles for SNS providers. Research design, data, and methodology - We developed 16 hypothesis based on media richness theory, social presence theory, social comparison theory, the literature about relative deprivation, and the literature about the various reactions of IS users. The rich SNS media, social presence recognition among peer SNS users, and prior life satisfaction could generate positive experience, attitude, and virtuous behavioral intentions among SNS users. At the same time, rich media, low social presence, and low prior life satisfaction could generate relative deprivation and could increase withdrawal behavioral intentions such as refusal to provide information, misrepresentation of information, and removal of uploaded information in SNS. Scenario surveys were conducted to collect data from potential SNS users. Data from 357 surveys were collected and analyzed through a PLS algorithm to test the hypotheses. Results - Media richness, social presence, and prior life satisfaction could significantly increase perceived enjoyment, satisfaction, and behavioral intention of continual usage and knowledge sharing. They also could significantly decrease refusal and misrepresentation intention. Relative deprivation is significantly decreased only by prior life satisfaction. Relative deprivation could not significantly decrease satisfaction, but it could significantly increase misrepresentation and removal intention, which could be regarded as information distortion intention. Conclusions - SNS providers should focus on developing rich media and social presence support because these two variables could impact the positive experiences of SNS users. Moreover, the positive experiences could heavily influence SNS user behavior. Some management is needed to prevent relative deprivation and its consequences of misrepresentation and removal intention. SNS providers should prevent SNS users from excessive image misrepresentation and removal as this information distortion could be the source of relative deprivation.

An Exploratory Study on the Structural Relationship of Brand Equity, Internal Brand, Conflict and Relationship Dissolution on Franchise System (프랜차이즈 시스템에서 브랜드 자산, 내부브랜드 활동, 갈등 및 관계해지의 구조적 관계에 관한 탐색적 연구)

  • Kim, Kyung-Min;Na, June-Hee;Lee, Young-Chan
    • Journal of Distribution Research
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    • v.12 no.1
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    • pp.65-84
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    • 2007
  • The relation between franchiser and franchisee participated the franchise system was studied focused on brand for the correlation of relationship dissolution. Basically the relation among brand equity, internal brand, conflict and relationship dissolution based on brand on franchise system were investigated. The study of external factor and internal one of brand recognized by franchisee was conducted. The questionnaire was carried out for franchisee participated of national franchise system. The results showed that the brand external factor of brand transaction cost, brand equity and brand communication had influence on brand dissolution by the affection of brand identification and conflict classified as brand internal factor. In addition, brand internal reinforcement factor affected brand dissolution also. The structural causal inference between internal factor and external one was examined. Finally, the theoretical and managerial insight were suggested on the brand role for the consecutive relation as well as the limit of the study and future suggestion were included.

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Brassica rapa Sec14-like protein gene BrPATL4 determines the genetic architecture of seed size and shape

  • Kim, Joonki;Lee, Hye-Jung;Nogoy, Franz Marielle;Yu, Dal-A;Kim, Me-Sun;Kang, Kwon-Kyoo;Nou, Illsup;Cho, Yong-Gu
    • Journal of Plant Biotechnology
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    • v.43 no.3
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    • pp.332-340
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    • 2016
  • Seed size traits are controlled by multiple genes in crops and determine grain yield, quality and appearance. However, the molecular mechanisms controlling the size of plant seeds remain unclear. We performed functional analysis of BrPATL4 encoding Sec14-like protein to determine the genetic architecture of seed size, shape and their association analyses. We used 60 $T_3$ transgenic rice lines to evaluate seed length, seed width and seed height as seed size traits, and the ratios of these values as seed shape traits. Pleiotropic effects on general architecture included small seed size, erect panicles, decreased grain weight, reduced plant height and increased sterility, which are common to other mutants deficient in gibberellic acid (GA) biosynthesis. To test whether BrPATL4 overexpression is deleterious for GA signal transduction, we compared the relative expression of GA related gene and the growth rate of second leaf sheath supplied with exogenous $GA_3$. Overexpression of BrPATL4 did not affect GA biosynthesis or signaling pathway, with the same response shown under GA treatment compared to the wild type. However, the causal genes for the small seed phenotype (D1, SRS1, and SRS5) and the erection of panicles showed significantly decreased levels in mRNA accumulation compared to the wild type. These results suggest that the overexpression of BrPATL4 can control seed size through the suppression of those genes related to seed size regulation. Although the molecular function of BrPATL4 is not clear for small seed and erect panicles of BrPALT4 overexpression line, this study provides some clues about the genetic engineering of rice seed architecture.

Examination of Correlations Between Several Biochemical Components and Powdery Mildew Resistance of Flax Cultivars

  • Aly, Aly A.;Mansour, Mahmoud T. M.;Mohamed, Heba I.;Abd-Elsalam, Kamel A.
    • The Plant Pathology Journal
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    • v.28 no.2
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    • pp.149-155
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    • 2012
  • A field trial was conducted in 2009/2010 and 2010/2011 growing seasons at Giza Agricultural Research Station to examine correlations between some biochemical componets and powdery mildews ($PM_s$) resistance in flax cultivars. Nine flax cultivars could be divided into five distinct groups, i.e., highly susceptible (Cortland and C.I. 2008), moderately susceptible (Giza 7, and Marshall), moderately resistant (Cass), resistant (Koto, Dakota and Wilden), and highly resistant (Ottowa 770B). The cultivars showed considerable variation in PM severity ranged from 8.05 on Ottowa 770B to 97.02% on Cortland. Total soluble proteins, total phenols, antioxidant enzymes (peroxidase and polyphenoloxidase), ascorbic acid, tocopherol, and malondialdehyde (MDA), were determined in uninfected leaves of the tested cultivars. Pearson's correlation coefficient was calculated to measure the degree of association between PM severity and each component. All components showed significant (P < 0.05) or highly significant (P < 0.01) negative correlation with PM severity except MDA, which showed positive correlation (P < 0.01). Linear regression analysis was used to evaluate the causal relationship between the biochemical components (independent variables) and PM severity (dependent variable). Coefficient of determination ($R^2$) values of the generated models ranged from 48.76 to 77.15%. Tocopherol, MDA, and proteins were the most important contributors to the total variation in PM severity as the $R^2$ values of their models were 71.78, 75.28, and 77.15%, respectively. The results of the present study suggest that tocopherol, MDA, and proteins in uninfected leaves can be used as biochemical markers to predict PM resistance in flax.

Pink Mold Rot on Asian Pear (Pyrus serotina Rehder) Caused by Trichothecium roseum (Pers.) Link ex Gray in Korea (Trichothecium roseum에 의한 배 분홍빛썩음병 발생)

  • Kwon, Jin-Hyeuk;Lee, Heung-Su;Choi, Si-Lim;Cho, Cho-Yong;Choi, Ok-Hee;Cho, Hyeoun-Suk;Shim, Chang-Ki
    • Korean Journal of Organic Agriculture
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    • v.21 no.3
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    • pp.373-380
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    • 2013
  • A severe pink mold rot on matured asian pear (Pyrus serotina Rehder) fruit occurred in the organic farmers' orchard in Jinju, Korea in October, 2012. Decay of pear fruit appeared as a softened water-soaked symptom that was easily punctured by pressure. Later pink mycelium appeared on the surface of pear fruit and produced a mass of powdery pink conidia spores. Optimum temperature for mycelial growth of T. roseum was $25^{\circ}C$. Conidia showed hyaline, smooth, 2-celled, thick-walled with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $10{\sim}22(34){\times}6{\sim}10(12){\mu}m$ in size. Conidiophore was erect, colorless, unbranched type, and 4-5 ${\mu}m$ width. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.