• Plant Biotechnology Reports
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• v.4 no.2
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• pp.149-155
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• 2010

Expression of the genes for carotenoid bio-synthesis (crt) is dependent on light, but little is known about the underlying mechanism of light sensing and signalling in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter, Synechocystis). In the present study, we investigated the light-induced increase in the transcript levels of Synechocystis crt genes, including phytoene synthase (crtB), phytoene desaturase (crtP), ${\zeta}$-carotene desaturase (crtQ), and ${\beta}$-carotene hydroxylase (crtR), during a darkto-light transition period. During the dark-to-light shift, the increase in the crt transcript levels was not affected by mutations in cyanobacterial photoreceptors, such as phytochromes (cph1, cph2 and cph3) and a cryptochrome-type photoreceptor (ccry), or respiratory electron transport components NDH and Cyd/CtaI. However, treatment with photosynthetic electron transport inhibitors significantly diminished the accumulation of crt gene transcripts. Therefore, the light induction of the Synechocystis crt gene expression is most likely mediated by photosynthetic electron transport rather than by cyanobacterial photoreceptors during the dark-to-light transition.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.1
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• pp.107-113
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• 2004

Several transition metal complexes, [$M(L)X_2$](M=Pd(II), Ni(II); X=CI, Br) are prepared with aminophosphine ligands such as 1,2-bis{(diphenylphosphino)amino}ethane{$Ph_2PNHCH_2CH_2NHPPh_2$}($L_1$), 1,2-bis{(diphenylphosphino)amino}propane{$Ph_2PNHCH(CH_3)CH_2NHPPh_2$}($L_2$), trans-1,2-bis{(diphenylphosphino)amino}cyclohexane{$Ph_2PNHC_6H_{10}NHPPh_2$}($L_3$) and 1,2-bis{(diphenylphosphino)amino}benzene{$Ph_2PNHC_6H_4NHPPh_2$}($L_4$). The properties of these complexes are characterized by optical spectroscopic methods including UV/vis spectroscopy, CD, IR, $^1H$- and $^{31}P-NMR$ together with conductometer and elemental analysis. All complexes are stable under atmospheric environment. Catalytic reactivity for C-C coupling between [$M(L)X_2$] and Grignard reagents(RMgX; R=phenyl, propyl, buthyl) by thermolysis were investigated utilizing GC/mass, $^1H$- and $^{13}C-NMR$. When mol scale is 1:20 at [$Pd(L)Cl_2$] and Grignard reagents, the high catalytic activity for C-C coupling is apparent. The [$M(L)X_2$](X=Cl, Br) complexes which have strong bond at M-P exhibit high yields for C-C coupling reactions. When the central metal ion is Pd(II), the high catalytic activity for C-C coupling is apparent. The complex coordinated with Br shows higher catalytic activity for C-C coupling reactions compared to Cl.

• Journal of Energy Engineering
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• v.23 no.2
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• pp.93-101
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• 2014

How to determine the extent of national energy security? In this paper, we estimate it by comparative analysis of South Korea and other OECD countries in terms of energy diversity (fuel diversity). Energy security consists of 4 key factors such as availability, accessibility, acceptability, affordability. Especially the importance of accessibility can grow as local imbalance of supply and demand increases. As a proxy of the accessibility, fuel diversity can be a significant indicator to estimate a measure of energy security. In this paper, we use Shannon-Wiener index to measure energy diversity. If fuel diversity increases, the stability of energy security also should increase, because of the smoothing effect to lessen dependence on key energy sources. In 2012 Korean growth rate of H-index (energy diversity) is 18.38%, which is higher than other OECD countries. However, Korean H-index itself is 1.93, lesser than other countries. Shift from oil to coals/gas within fossil fuels has more impact on H-index than weight transition from fossil fuels to renewable energies in Korea. We conclude that more renewable energy is an effective solution to achieve higher energy diversity and ultimately higher energy security as the same as the German case.

• Journal of Service Research and Studies
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• v.9 no.4
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• pp.63-80
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• 2019

This study presents strategic implications for enhancing the competitiveness of the comprehensive health examination center through the study of its impact on the switching barrier with medical service value and medical service satisfaction as parameters. In order to achieve the purpose of this study, a total of 324 questionnaires were analyzed for customers who received health examinations at the general examination center. Covariance structure analysis was performed to test hypotheses and causal relationships. The results showed that the physical environment had a significant effect on the medical service value and medical service satisfaction. The value of medical service also had a significant effect on medical service satisfaction. The value of medical service was found to affect the transition barrier, but the satisfaction of medical service did not affect the transition barrier. The implications of this study are that physical environment has a significant effect on medical service value and medical service satisfaction. Therefore, modern medical equipment should be equipped with the latest medical equipment to minimize accurate examination and misdiagnosis through modernization of medical examination center. In addition, since the value of medical service has a significant effect on the switching barrier, it is necessary to establish a plan to enhance the value of medical service. We need to promote sustainable customer retention and creation of new customers through differentiated screening items and cost advantages over competitors. In addition to check-up services, efforts should be made to enhance the value of services such as strengthening medical communication and medical complex cultural spaces, and at the same time, establish an organizational culture of customer-first examination centers through the placement of excellent personnel and continuous education.

• Human Ecology Research
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• v.51 no.6
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• pp.603-612
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• 2013

With the increase of single-parent families in the Korean society, the perception of the function and structure of the family is changing. Thus, a public transition toward embracing single-parent families as another form of family is necessary. This study focuses on the families of divorced female single-parents using Walsh's family resilience framework with a strengths-based perspective. It aims to provide the basic data necessary for deducing policy-related and practical ways of supporting the families and for developing programs that help divorced female single-parent families maintain and reinforce resilience. Qualitative analysis was used as the research method. A preceding literature review was also carried out to collect data. The major findings of this study include the following: First, it was found that the average age of divorce is around 30-40, with children of school age. The mothers' level of education was relatively high, ranging from high school graduates to graduate school students. On Rothwell and Cohen's happiness scale, their objective level of happiness was higher (74.1) than that of the average Korean (64). Second, it was found they were very careful to avoid violence in everyday life as an after-effect of domestic violence, which was the major cause of their divorce. Third, their positive and optimistic attitudes about life even in adversity can be interpreted as Walsh's belief systems taking a more important role among other characteristics of family resilience.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.99-101
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• 2015

Massive stars are some of the most influential objects in the Universe, shaping the evolution of galaxies, creating chemical elements and hence shaping the evolution of the Universe. However, the processes by which they form and how they shape their environment during their birth processes are not well understood. We use $NH_3$ data from "The $H_2O$ Southern Galactic Plane Survey" (HOPS) survey to define the positions of dense cores/clumps of gas in the southern Galactic plane that are likely to form stars. Then, using data from "The Millimetre Astronomy Legacy Team 90 GHz" (MALT90) survey, we search for the presence of infall and outflow associated with these cores. We subsequently use the "3D Molecular Line Radiative Transfer Code" (MOLLIE) to constrain properties of the infall and outflow, such as velocity and mass flow. The aim of the project is to determine how common infall and outflow are in star forming cores, and therefore to provide valuable constraints on the timescales and physical process involved in massive star formation. Preliminary results are presented here.

• Journal of Electrochemical Science and Technology
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• v.15 no.2
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• pp.207-219
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• 2024

Metal-N-C (MNC) catalysts have been anticipated as promising candidates for oxygen reduction reaction (ORR) to achieve low-cost polymer electrolyte membrane fuel cells. The structure of the M-N_x moiety enabled a high catalytic activity that was not observed in previously reported transition metal nanoparticle-based catalysts. Despite progress in non-precious metal catalysts, the low density of active sites of MNCs, which resulted in lower single-cell performance than Pt/C, needs to be resolved for practical application. This review focused on the recent studies and methodologies aimed to overcome these limitations and develop an inexpensive catalyst with excellent activity and durability in an alkaline environment. It included the possibility of non-precious metals as active materials for ORR catalysts, starting from Co phthalocyanine as ORR catalyst and the development of methodologies (e.g., metal-coordinated N-containing polymers, metal-organic frameworks) to form active sites, M-N_x moieties. Thereafter, the motivation, procedures, and progress of the latest research on the design of catalyst morphology for improved mass transport ability and active site engineering that allowed the promoted ORR kinetics were discussed.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.136-141
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• 2010

North Korean defectors who settle in South Korea have experienced severe food shortage and transition of food environment which could affect their health status. However, little is known about their anthropometric measurements and dietary intake after settlement in South Korea. The purpose of this study is to compare anthropometric measurements and dietary intake between North Korean young adults who defected to South Korea and those of South Koreans. We hypothesized that North Korean young adults' physiques and dietary intake would be poorer than that of South Koreans. We compared anthropometric measurements and dietary intake from 3-day food records in a cross-sectional study of 103 North Korean young adult defectors, aged 12 to 24 and 309 South Korean subjects. North Korean subjects were significantly shorter (4.9 to 10.8 cm) and lighter (6.0 to 12.5 kg) than the control group. Body mass index were significantly different between North and South Korean groups only in men. North Korean young adult defectors had lower mean daily intakes of energy and most nutrients and food groups compared to the control group, while North Korean subjects had higher nutrient density diet than that of South Koreans. The proportion of subjects who had dietary intakes of nutrients of less than the Estimated Average Requirement was higher in North Korean subjects than in controls except for in the cases of vitamin A and vitamin C. In conclusion, we recommend providing nutrition support programs for North Korean young adult defectors to secure adequate nutrient intake.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.1
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• pp.1-13
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• 2010

Gravure printing and manufacturing of advanced electronic components in a way that is going extra hold position. It is to print the electronic components of the rapid productivity improvements as well as cost-saving and environment-friendly industries such as the transition is a big advantage. However the mechanism of gravure is difficult to study scientifically because of high speed and excessively small size of the cell. To approach the mechanism we experimented using gravure printability. The condition of variables of IGT is pressure and velocity. By using Flow-3D simulation software, we built up the theoretical model under the constant variables. Then, we compared the real test with the simulation results. Therefore, it is studied the mechanism of gravure scientifically and it can be analysed the effect of the variable conditions.

• The Plant Pathology Journal
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• v.17 no.3
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• pp.169-173
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• 2001

Virus disease occurred up to 62% in average in the greenhouse production of table tomato Seokwang in Suwon, Korea. From symptomatic transition of the labeled tomatoes, two different symptoms, mosaic and bud necrosis, were developed independently. Cucumber mosaic virus necrosis strain (CMV-N) was isolated from table tomato showing bud necrosis symptoms. The isolate caused the bud necrosis on four tomato cultivars and locally infected Chenopodium spp. and Vicia faba by mechanical inculation. The 5th RNA segment, satellite RNA, was identified from CMV-N-infected plants by dsRNA analysis. Crystals of virus particles were observed in cytosols and vacuoles. The virus particles of CMV-N presented abundantly in xylem vessel.