• Progress in Superconductivity
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• v.4 no.2
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• pp.144-147
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• 2003

We investigated superconducting property of ($Mg_{1-x}$$Zn_{x}$)$CNi_3$ (x=0,0.03, 0.06, 0.09, 0.12, 0.15, and 0.18) sample where Mg is substituted with Zn. The samples were synthesized us ins the solid state reaction method under As atmosphere. X -ray diffraction spectra show that the $MgCNi_3$ structure is maintained up to x=18. With increasing x, the lattice constant (or the Ni-Ni distance) decreases. Magnetic susceptibility measurement shows that $T_{c}$ decreases systematically with x and becomes ～2K at x =0.18. Surprisingly, the transition width remains sharp (～0.3K). Under some assumptions, we estimate the coupling constant in the McMillan formula as a function of x which we interpret in terms of the BCS theory.y.y.y.

• The Korean Journal of Community Living Science
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• v.26 no.2
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• pp.335-349
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• 2015

The system of School Meal Service Support Centers was established to support the supply of high-quality food ingredients for school meal services when the School Meal Service Act was amended in 2006. A case study was conducted to examine the operating effects, success factors, and major obstacles of a School Meal Service Support Center which was highly evaluated for its operational efficiency and customer satisfaction. Qualitative data were collected from eight stakeholders (two individuals each from the center, farms, schools, and distributors) through in-depth interviews in July 2013 and analyzed by using the thematic analysis method. The successful operation of the center helped to stabilize income and price among the stakeholders, increase ingredient quality, increase school meal reliability, reduce costs, and promote the consumption of agricultural products. Success factors were identified as the center director's commitment and insights, and the competitive operating system including fair operations, rational pricing, liberal consumer choice, total quality management, and partnerships with distributors. Major obstacles included a lack of diversity in supplied ingredients and a lack of administrative and financial support form the local government. The results can be used as baseline information to vitalize the system of School Meal Service Support Centers and increase the quality of school meal services.

• Human Ecology Research
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• v.61 no.4
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• pp.709-721
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• 2023

This study aimed to enhance awareness of diverse families and promote an inclusive, family-friendly culture by implementing the metaverse in a family festival and assessing its effects during the Covid-19 pandemic. To achieve this, the metaverse was applied and operated at the Jung-gu Family Center Family Festival in Seoul from October 29 to November 6, 2021. The design of the Metaverse Family Festival prioritized the integration of metaverse technology and the layout of program-linked spaces to create a realistic experience. The festival was operated with a focus on providing experiential activities and exhibitions. Data comprised program satisfaction and reviews from a sample of 228 festival participants. The key findings were as follows. Firstly, participants shared their interest and joy in experiencing new activities with their families through the Metaverse Family Festival. Secondly, creating a realistic family festival environment proved practical for encouraging active participation. Thirdly, the Metaverse Family Festival was perceived as promoting an inclusive, family-friendly culture by facilitating safe and accessible communication. Fourthly, the festival effectively bridged the digital gap within families, thereby enhancing digital literacy. This study offers new insights for the future design and operation of various programs in family centers and public institutions.

• Journal of Microbiology
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• v.33 no.4
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• pp.339-343
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• 1995

We isolated a 10 kb Bam HI fragment originated from the chromosome of a $H_2O$$^2$-resistant mutant strain of Streptomyces coelicolor, which confer $H_2O$$^2$-resistance to S. lividance upon transformation. Among various subclones ot 10kb Bam HI fragment tested for their $H_2O$$^2$-resistant phenotype in S. lividans, a subclone containing 5.2 kb Bam HI-BglII fragment was found to be responsible for $H_2O$$^2$-resistance. The plasmid containing this 5.2 kb fragment was then transformed into S. coellicolor A3(2) at early and tested for their phenotype of $H_2O$$^2$-resistance and the change in various enzymes whose activity can be stained in the gel. We found out that the 5.2 kb insert DNA conferred $H_2O$$^2$-resisstance in S. coelicolor A3(2) at early phase of cell growth. The presence of this DNA also resulted in higher level of peroxidase compared with the wild type cell containing parental vector (pIJ702) only. Esterase activity was also higher in this clone. However, alcohol dehydrogenase activity decreased compared with the wild type. These results suggest that the presence of a gene in 5.2 kb BamHI-BglII DNA fragment causes multiple changes in S. coelicolor related to its response against hydrogen peroxide. The result also implies that not only peroxidase but also esterase may function in the defencse meahsnism agianst $H_2O$$^2$-.

• Safety and Health at Work
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• v.12 no.3
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• pp.377-383
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• 2021

Background: This study investigated the longitudinal associations between the degrees of positive and negative spillover in work-life balance (WLB) at baseline and reports of depressive mood at a 2-year follow-up in Korean women employees. Methods: We used a panel study design data of 1386 women employees who participated in the Korean Longitudinal Survey of Women and Families in both 2014 and 2016. Depressive mood was measured using the "10-item Center for Epidemiologic Studies Depression Scale." Associations between the positive and negative spillover in WLB at baseline and reports of new incidence of depressive mood at 2-year follow-up were explored using a multivariate logistic regression model. Results: Negative spillover in WLB at baseline showed a significant linear association with reports of depressive mood at 2-yearfollow-up after adjusting for age, education level, marital status, number of children, and positive spillover (P = 0.014). The highest scoring group in negative spillover (fourth quartile) showed a significant higher odds ratio of 1.95 compared with the lowest scoring group (first quartile; P = 0.036). Conclusion: Positive spillover in WLB showed a U-shaped association with depression. The degrees of positive and negative spillover in WLB among Korean women employees at baseline were associated with new incidence of depressive mood within 2 years. To prevent depression of female workers, more discrete and differentiated policies on how to maintain healthy WLB are required.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.297-298
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• 2003

Chitin is a natural biopolymer that, with its derivative chitosan, has been represented as a biomaterial with considerable potential in wide ranging medical applications. But there are some limitations in using chitosan as attained, for instance, the problem of water solubility$^1$. In order to use chitosan in various applications (e.g. drug carrier), chemical modifications are often necessary$^2$. (omitted)

• Applied Biological Chemistry
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• v.41 no.4
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• pp.273-274
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• 1998

In vitro cytotoxicity of sambutoxin was measured by using various human and murine tumor cells and $IC_{50}$ values of sambutoxin ranged from 46.2 to 1,425.6 ng/ml.

• Journal of Applied Biological Chemistry
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• v.43 no.2
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• pp.117-118
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• 2000

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2304-2310
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• 2014

The synthesis and in vivo evaluation of 5-methoxy-2-(phenylethynyl)quinoline (MPEQ) 3 as a potential mGluR5 selective radioligand is described. We have identified MPEQ 3 exhibiting the analgesic effect in the neuropathic pain animal model. The effect of mGluR5 on neuronal activity in rat brain was evaluated through FDG/PET imaging in the presence of MPEQ 3. In addition, the PET study of [$^{11}C$]MPEQ 3 proved that accumulation of [$^{11}C$]MPEQ 3 in rat brain was correlated to the localization of the mGluR5.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.335-343
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• 2005

Inorganic bovine bone mineral has been widely researched as bone substitution materials in orthopedic and oral and maxillofacial application. OCS-B(NIBEC, Korea) is newly-developed inorganic bovine bone mineral. The aim of this study is to evaluate the safety and efficacy of bovine bone-derived bone graft material(OCS-B). Micro-structure of newly-developed inorganic bovine bone mineral(OCS-B) was analyzed by scanning electron microscope(SEM). Round cranial defects with eight mm diameter were made and filled with OCS-B in rabbits. OCS-B was inserted into femoral quadrant muscle in mouse. In scanning electron microscope, OCS-B was equal to natural hydroxyapatite. Rabbits were sacrificed at 2 weeks and 4 weeks after surgery and mice were sacrificed at 1 week and 2 weeks after surgery. Decalcified specimens were prepared and observed by microscope. In calvarial defects, osteoid and new bone were formed in the neighborhood of OCS-B at 2 weeks after surgery. And at 4 weeks after surgery osteoid and new bone bridge formed flourishingly. No inflammatory cells were seen on the surface of OCS-B at 1 week and 2 weeks in mouse experimental group. It is concluded that newly-developed inorganic bovine bone mineral(OCS-B) is a flourishing bone-forming material and biocompatible material.