• Title/Summary/Keyword: 자기 감수성

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Functional analysis of seaR protein identified from Saccharopolyspora erythraea (희소방선균의 seaR 단백질 발현을 통한 기능 분석)

  • Ryu, Jae Ki;Kwon, Pil-Seung;Lee, Hyeong Seon
    • Korean Journal of Microbiology
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    • v.51 no.1
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    • pp.39-47
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    • 2015
  • Secondary metabolism in actinomycetes has been known to be controlled by a small molecule, ${\gamma}$-butyrolactone autoregulator, the binding of which to each corresponding receptor leads to the regulation of the transcriptional expression of the secondary metabolites. We expected that expression of an autoregulator receptor or a pleiotropic regulator in a non-host was to be gained insight of effective production of new metabolic materials. In order to study the function of the receptor protein (seaR), which is isolated from Saccharopolyspora erythraea, we introduced the seaR gene to Streptomyces coelicolor A3(2) as host strains. An effective transformation procedure for S. coelicolor A3(2) was established based on transconjugation by Escherichia coli ET12567/pUZ8002 with a ${\varphi}C31$-derived integration vector, pSET152, which contained int, oriT, attP and $ermEp^*$ (erythromycin promotor). Therefore, the pEV615 was introduced into S. coelicolor A3(2) by conjugation and integrated at the attB locus in the chromosome of the recipients by the ${\varphi}C31$ integrase (int) function. Exconjugant of S. coelicolor A3(2) containing the seaR gene was confirmed by PCR and transcriptional expression of the seaR gene in the transformant was analyzed by RT-PCR. In case of S. coelicolor A3(2), a phenotype microarray was used to analyze the phenotype of transformant compared with wild type by seaR expression. After that, in order to confirm the accuracy of the results obtained from the phenotype microarray, an antimicrobial susceptibility test was carried out. This test indicated that sensitivity of the transformant was higher than wild type in tetracycline case. These results indicated that some biosynthesis genes or resistance genes for tetracycline biosynthesis in transformant might be repressed by seaR expression. Therefore, subsequent experiments, analysis of transcriptional pattern of genes for tetracycline production or resistance, are needed to confirm whether biosynthesis genes or resistance genes for tetracycline are repressed or not.

The Factors Affecting Hepatitis B Vaccination of Dental Hygiene Students (일부 치위생과 학생의 B형간염 예방접종에 영향을 미치는 요인)

  • Yu, Ji-Su;Hwang, Su-Hyun;Han, Yang-Keum
    • Journal of dental hygiene science
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    • v.15 no.2
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    • pp.138-144
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    • 2015
  • The purpose of this study was to investigate the differences in health belief related to vaccination among dental hygiene students, identify the factors affecting hepatitis B vaccination, and provide basic data for health education concerning hepatitis B prevention. Hepatitis B vaccination was positively correlated (r=0.179, p=0.003) with seriousness of believing that hepatitis B would affect psychological, physical, and social activities and negative correlation (r=-0.183, p=0.002) was also found between perceived barriers related to hepatitis B. As for the factors affecting hepatitis B vaccination, juniors were 0.39 times (95% confidence interval [CI]=0.21, 0.71) more likely to have it affected than seniors and those who were more serious, and who had greater barriers were more likely to have it affected-1.80 times (95% CI=1.29, 2.52), 0.61 times (95% CI=0.41, 0.90) respectively (p<0.05). It is therefore urgent to develop a program within a curriculum that can begin with freshmen along with specific education with the objective of obliging dental hygiene students to receive hepatitis B vaccination. It is also necessary to provide consecutive sessions of education rather than one-time education and to develop a specific plan for obligatory hepatitis B vaccination through correct and thorough education.

A Study on Cinematic Representations of Posthuman Girls in South Korea-Focused on The Silenced and The Witch: Part 1. The Subversion (한국 영화에 나타난 포스트휴먼 소녀의 재현 양상 연구 -<경성학교: 사라진 소녀들>, <마녀>를 중심으로)

  • Kim, Eun Joung
    • Journal of Popular Narrative
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    • v.27 no.3
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    • pp.95-124
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    • 2021
  • As the symbolic images of girls besides its definition have varied according to the age and society, a posthuman girl character recently appears in the digital cinema. This study aims to analyze its cinematic representations and the social contexts in which they are created. For this purpose, the study focuses on what extent the society allows its imagined figurations as a future female body and the meanings revolving around the image of 'technologically body-enhanced female fighter'. Current digital visualization technology has developed to the extent any imaged future humans can be represented, but posthuman girls' representations have its limitation that only a human-like figuration can be allowed in accord with the traditionally idolized image of girls. It is because of the representation logic in which digital cinema is visualized based on perceptual realism that values audiences' experiences. Despite such less critical figuration which does not dare to cross the boundary between the image of human and inhuman, the posthuman girl characters create a new category of the 'dangerous girls' who are both void of sexual femininity and independent of motherhood and heterosexual romance narrative. Of course, they support the modern human-centered belief that humans can take entire control of technology with their moral behaviors and dispel the fear about the negative impact the nature of technology may have on society at large by showing their child-like figuration protecting ethical values. However, the new character of 'unruly girl' exerts her subversive act that seeks to fight against the human-centered liberal humanistic values and melancholic feeling and vulnerability that the neoliberalism and technocracy enforce. When posthuman girl characters are considered to be a marker through which we can see how different social forces are intervening and competing each other in the upcoming posthuman age, the limited figuration of the posthuman girl characters in South Korean movies illustrates the opinionated thoughts toward the instrumentalism in technology but their bloodshed struggles reveal how the corporate or state-governed techno-biopower has oppressively treated and appropriated the human body as the technology-object and also provide a meaningful opportunity to rethink its unethical violence.

The Impact of Entrepreneurs' Cognitive Biases on Business Opportunity Evaluation Depending on Social Networks (기업가의 인지편향이 사회적 네트워크에 따라 사업 기회 평가에 미치는 영향)

  • Jang, Hyo Shik;Yang, Dong Woo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.185-196
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    • 2023
  • This paper investigates the effects of entrepreneurs' cognitive biases on business opportunity evaluation, given their strong entrepreneurial spirit, which is characterized by innovation, proactivity, and risk-taking. When making decisions related to business activities, entrepreneurs typically make rational judgments based on their knowledge, experience, and the advice of external experts. However, in situations of extreme stress or when quick decisions are required, they often rely on heuristics based on their cognitive biases. In particular, we often see cases where entrepreneurs fail because they make decisions based on heuristics in the process of evaluating and selecting new business opportunities that are planned to guarantee the growth and sustainability of their companies. This study was conducted in response to the need for research to clarify the effects of entrepreneurs' cognitive biases on new business opportunity evaluation, given that the cognitive biases of entrepreneurs, which are formed by repeated successful experiences, can sometimes lead to business failure. Although there have been many studies on the effects of cognitive biases on entrepreneurship and opportunity evaluation among university students and general people who aspire to start a business, there have been few studies that have clarified the relationship between cognitive biases and social networks among entrepreneurs. In contrast to previous studies, this study conducted empirical surveys of entrepreneurs only, and also conducted research on the relationship with social networks. For the study, a survey was conducted using a parallel survey method using online mobile surveys and self-report questionnaires from 150 entrepreneurs of small and medium-sized enterprises. The results of the study showed that 'overconfidence' and 'illusion of control', among the independent variables of entrepreneurs' cognitive biases, had a statistically significant positive(+) effect on business opportunity evaluation. In addition, it was confirmed that the moderating variable, social network, moderates the effect of overconfidence on business opportunity evaluation. This study showed that entrepreneurs' cognitive biases play a role in the process of evaluating and selecting new business opportunities, and that social networks play a role in moderating the structural relationship between entrepreneurs' cognitive biases and business opportunity evaluation. This study is expected to be of great help not only to entrepreneurs, but also to entrepreneur education and policy making, by showing how entrepreneurs can use cognitive biases in a positive way and the influence of social networks.

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Studies on Controlling Mixed Annual and Perennial Weeds in Paddy Fields - On the Herbicidal Properties of Perfluidone - (수종(數種) 다년생잡초혼생답(多年生雜草混生沓)에 있어서 제초제(除草劑)에 의한 효과적(效果的)인 잡초방제(雜草防除) - Perfluidone의 작용특성구명(作用特性究明)을 중심(中心)으로 -)

  • Ryang, H.S.;Han, S.S.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.75-99
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    • 1983
  • The herbicidal properties of perfluidone [1,1,1-trifluoro-N-2-methyl-4-(phenylsulponyl) phenyl methanesulfonamide] were investigated in pots and paddy fields. At the rate of 2.0kg prod./10a, perfluidone did not cause any injury to the 4 leaf stage (LS) rice seedlings. Although the crop injury increased with increasing the application rate, the injury caused by 16kg prod. perfluidone/10a gave rise to only 30% yield reduction. The crop injury was greatest when perfluidone was applied 2 days before transplanting and decreased as the application time delayed. Perfluidone showed greater crop injury to the 3 LS seedlings, at more than 7cm water depth, and at high temperature than to the 4 LS seedlings, at 3-5cm water depth, and at low temperature. Indica and indica ${\times}$ japonica rice varieties were generally more sensitive to perfluidone than japonica rice variety. Perfluidone effectively controlled most of annual weeds and such perennial weeds as Sagittaria pygmaea MIQ., Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB, Scirpus maritimus L., Eleocharis kuroguwai OHWL, and Scirpus hotarui OHWL, whereas Sagittaria trifolia L. and Polygonum hydropiper SPACH. were tolerent to perfluidone. The weeding effect decreased with increasing the leaching amount of water and the overflowing of irrigated water within 24 hours after the herbicide application. When the application time was done later than 8 days after transplanting, the perennial weeds were shown at deeper soil layers, and the standing water was deeper than 7cm, the effect tended to decrease. However, there was no difference in the weeding effect between soil types. Downward movement of perfluidone in flooded soil ranged from 2 to 8cm deep. The movement increased with increasing the leaching amount of water and the application rate and at a sandy loam soil which possessed less adsorptive capacity. Residual effect of perfluidone was found at 35 to 80 days after application, which varied such factors as Soil types. Increase in the leaching amount of water resulted in decrease in the period of the residual effect. The period was shorter at non-sterilized soil than at sterilized soil. The 0.75kg ai perfluidone + 1.5kg ai SL-49 (1,3-dimethyl-6-(2,4-dichlor-benzoyl)-5-phenacyloxy-pyrazole)/ha and 1.5kg ai perfluidone + 1.05kg ai bifenox (2,4-dichlorophenyl-3-methoxy carbonyl-4-nitro phenyl ether)/ha showed less crop injury than 1.5kg ai/ha perfluidone alone. However, the weeding effect of the former was similar to that of the later.

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