• 베이커리
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• no.11 s.352
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• pp.142-147
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• 1997

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.64-69
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• 2004

The deficiency of the neurotransmitter acetylcholine(ACh) is responsible for the initiation of Alzheimer's disease. In addition, there is a simple evidence that oxidative stress significantly increases in persons with Parkinson's disease compared to age-matched healthy persons. Therefore, the objective of the study was to investigate the neurodegeneration inhibitory effect of soybean(Glycine Max) and Yak-Kong(Rhynchosia Nolubilis) by measuring the degree of inhibiting Acetylcholinesterase (AChE) catabolizing the ACh and the free radical scavenger effect in vitro. AChE was measured by the minor modified Ellman assay. Free radical scavenging activity was measured using l-diphenyl-2-picrylhydrazyl (DPPH). First, the MeOH extracts of Soybean and Yak-Kong showed the AChE inhibiting activity of 62.0$\pm$2.43％ and 65.0$\pm$3.29％ at the 5 mg/$m\ell$ concentration. The 50％ inhibitory concentration ($IC_{50}$/) of AChE was 1.96 and 1.31 mg/$m\ell$ in the MeOH extracts of soybean and Yak-Kong. Second, the MeOH extracts of soybean and Yak-Kong showed the free radical scavenger activity of 23.1$\pm$4.26％ and 80.7$\pm$4.61％ at the 5 mg/$m\ell$. IC50 of free radical scavenger activity in Soybean and Yak-Kong was 13.00 and 1.41 mg/$m\ell$ in MeOH extracts and was 5.95 and 2.74 mg/$m\ell$ in hot-water extracts, respectively. In this study, the extracts of Soybean and Yak-Kong showed powerful effects in the AChE inhibition and free radical scavenging. The extracts of Soybean and Yak-Kong were expected to prevent the many neurodegenerative diseases.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.444-450
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• 2006

Skin anti-aging effect of Forsythia viridissima L. extract was evaluated by using antioxidant assay, expression of type I procollagen, and UVA-induced matrix metalloproteinase-1 in human dermal fibroblasts. Matairesinol-rich Forsythia viridissima L. extract was showed the scavenging activity of radicals and reactive oxygen species with the $IC_{50}$ values of $4.50\;{\mu}m/ml$ against 1,1-diphenyl-2-picrylhydrazly radical and $542.43\;{mu}m/ml$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. The type I procollagen was increased 33.76% by treatment with matairesinol-rich Forsythia viridissima L. extract, and UVA-induced MMP-1 was reduced 35.78% in a dose dependent manner. In the human skin irritation test, 2% matairesinol-rich Forsythia viridissima L. extract did not show any adverse effect. Also, the clinical study indicated that a cream group treated with 0.2% matairesinol-rich Forsythia viridissima L. extract significantly reduced skin wrinkles, as compared with a non-treated cream group (p < 0.05). These results suggest that Forsythia viridissima L. extract may be useful as a potential source of functional anti-aging cosmetics.

• Journal of Life Science
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• v.20 no.6
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• pp.877-884
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• 2010

We investigated the growth inhibitory effect of internal organs of Aplysia kurodai (AK) on proliferation in cancer cell lines in vitro. The internal organs of AK were extracted with methanol (AKM), which were then further fractionated into four subfractions by using solvent partition method, resulting in hexane (AKMH), methanol (AKMM), butanol (AKMB), and aqueous (AKMA) soluble fractions. We determined the cytotoxic effect of these four fractions in four kinds of cancer cell lines - HepG2, MCF-7, HT29 and B16-F10 - by MTT assay. Among the four subfractions of AKM, AKMM showed the strongest cytotoxic effects on all cancer cell lines which were used. Morphological changes such as membrane shrinking and blebbing of cells were also observed in AKMM treatment in HepG2 cells. In addition, we also observed quinone reductase (QR) induced effect in the methanol layer (AKMM) of HepG2 cells. AKMM showed the highest induction activity of quinone reductase on HepG2 cells among the partition layers. The QR induced effect of AKMM was determined to be 2.4 at $100\;{\mu}g/ml$ level with a control value of 1.0. Although further studies are needed, the present work suggests that internal organs of Aplysia kurodai (AK) may be a chemopreventive agent for the treatment of human cells.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.267-273
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• 1997

Various physico-chemical and microbiological parameters of a composting system were compared with respect to their potential use for the monitoring and evaluation of composting processes for cattle manure. The temperature changed within a range of $30-65^{\circ}C$ during the whole composting process, and the period of active composting (>$40^{\circ}C$) persisted for 16 days. The concentrations of total carbon, total nitrogen, and organic matter decreased by 15% during active composting, but significant changes in C/N ratio were not observed. The decrease of temperature in the latter period of active composting caused a decrease of $NH_4^+-N$ and an increase of $NO_3^--N$ in the composting pile. When temperature exceeded $50^{\circ}C$, the population of thermophiles was higher than that of mesophiles by more than 1 or 2 orders of magnitude. Correlation analyses showed that amylase activity correlated positively with the population of mesophiles and reducing sugar content, but negatively with the population of thermophiles. Amylase activity was higher at the beginning of active composting, whereas cellulase, xylanase and ligninase activities which showed close relationship with each other, increased continually during active cornposting, suggesting the distinction of temporal niches between amylose-degrading and lignocellulose-degrading bacteria in the same habitat.

• Journal of The Korean Association For Science Education
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• v.27 no.7
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• pp.570-582
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• 2007

The purpose of this study was to analyze the causal relationship among students' science-related career choice and its factors. The causal relationship was analyzed using structural equation modeling. According to the most fitting model, science career aspiration had a direct and total effect of 0.95 (standardized coefficient) on the science career choice, and personal factor had an indirect and total effect of 0.75 on the science career choice, educational factor, 0.46, and social factor, 0.11. Personal factor had a direct and total effect of 0.79 on the science career aspiration, educational factor with total effect of 0.48 (direct effect -0.21, indirect effect 0.69), and social factor with direct and total effect of 0.12. On the other hand, educational factor had a direct and total effect of 0.72 on the social factor, and a direct and total effect of 0.77 on the personal factor. The difference in the causal effect among grades and between gender was analyzed. The difference was only in the magnitude of influence among grades, showing the same tendency with the total number of students, but the difference between gender was contrastive. For the boys, social factor had the biggest effect on the science career choice, next was personal factor, and the educational factor had the smallest effect. The girls' science career choice influenced mostly from personal factor, and the other two factors' effects were not high. The social effect was negative for the girls' science career choice. The implications of proper science career education were discussed from these results, considering the causal relationship among factors of science career choice and its factors.

• Journal of Labour Economics
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• v.32 no.2
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• pp.125-150
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• 2009

This article analysed the effect of government intervention on the market failure in firm training in Korean. I used the Employment Insurance DB and the KISLINE DB and joined two data by the firm identification number 2004-2006 year. I estimated the effect of intervention of government by propensity score matching and difference-in-difference method to avoid of participation selection and endogeneity problem. The result is that government intervention on the firm training have made positive effect but it is not significant statistically. We have to investigate the market failure in firm training and to reassess the level of optimal firm training in Korea. After the study, the government intervention on the firm trainig will have to be rearranged.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.743-752
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• 2016

This study aims to investigate the overall effects of teaching grammar in the Korean EFL classroom. A meta-analysis of 67 research findings in 30 articles was conducted to synthesize the results of these studies by calculating the mean effect sizes. This study reviewed and analyzed the previous studies in terms of subjects, treatment period, and types of grammar teaching. The results showed that teaching grammar in the classroom had beneficial effects on learners in general (d=.907). It was found to be more effective for middle school and university students than for elementary and high school students (Q=37.065, df=3, p=.000). There was no statistically significant difference in terms of treatment period and types of grammar teaching. Pedagogical implications and suggestions for Korean EFL learners are also discussed.

• 한국벤처창업학회:학술대회논문집
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• 2024.04a
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• pp.17-20
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• 2024

우리는 대표적인 디지털 플랫폼인 온라인 음식 주문 배달 산업을 대상으로 디지털 경제의 긴꼬리 효과를 계량화한다. 특히, 코로나19 시기를 거치면서 음식배달플랫폼 입점으로 인한 긴꼬리 효과의 변화 양상을 고찰한다. 배달의민족에 입점한 음식점 15,000곳을 무작위로 선별하고 이들 매장의 2019년부터 2021년까지 전체 주문 정보를 취합(aggregation)하여 선형로그변환 후 기울기를 추정하여 디지털 경제의 긴꼬리 효과를 실증 분석하였다. 2019년부터 2021년까지 관찰기간 동안 음식 배달 플랫폼 활용 음식점 주비모수 분포의 긴꼬리 효과는 강건하게 관찰되었다. 이는 코로나19 이후 음식배달 플랫폼을 통한 음식점의 디지털 전환이 틈새시장 확장에 일정 부분 기여하였음을 의미한다. 또한, 긴꼬리 효과는 객단가가 높을수록 매출액 상위 집단일수록 더 커지는 반면, 비황금 시간대 매출비중이 높은 경우 긴꼬리 효과가 통계적으로 유의하게 증가하지 않았다. 이 결과는 피자, 족발 등 단가가 높고 비교적 배달서비스가 활발한 카테고리에서 음식 주문 및 배달 산업의 디지털 전환 효과가 증가한다는 업계 실무자들의 관찰과 부합한다. 타 업종에서도 상대적으로 경쟁이 치열한 시장 구분에서 디지털 경제의 긴꼬리 효과가 보다 강건하게 관찰될 것이라고 여겨진다. 음식점 간 경쟁강도가 상대적으로 약한 비황금시간대 매출비중이 긴꼬리 효과에 통계학적으로 유의한 영향을 주지 않는다는 실증결과 또한 동일한 함의가 있다.

• Korean Educational Research Journal
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• v.40 no.2
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• pp.17-33
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• 2019

This study examines the fundamental ethics of practice that Dasan Jung Yak-yong(1762-1836) argued at the book, "Dàxuégōngyì大學公議, The Public debate of Great Learning", by investigating the relationship between main agents of education. "Dàxuégōngyì", the book that Dasan wrote when he was 53 years old at his exiled place, Gangjin. As the title suggested, Dàxuégōngyì, it could be recognized as the impartial view based on the critical perspective to Zhūxǐ(朱憙)'s opinion. Zhuxi focused on the importance of "Great Learning 大學" as a study of the Great people and argued that "Great Learning" is the study for all the people should learn. On the other hand, Dasan claimed that "Tàixuézhīdào太學之道" in "Great Learning" is the study for the prince, not for the normal people. And he also interpreted "Dàxué 大學" as the school for teaching prince. In addition, "Great Learning" suggested the three practical principles; to illustrate illustrious virtue; to renovate the people; and to rest in the highest excellence. However, Dasan argued different way and emphasized three ethics of practice; filial piety(孝), admiration(弟), mercy(慈) and regarded as illustrious virtue of "Great Learning." He denied the three principle of "Great Learning" that Zhuxi reorganized and suggested including renovating the people(新民), and provided that close to the people(親民) is one of the main principles of "Great Learning." According to Dasan, if the king practices these three ethics of practice including filial piety, admiration, and mercy, so that the people will practice these ethics voluntarily. In other words, he indicated that the practice of three ethics is not only for the prince in the loyal family, but also for principles to educate the people in the nation. Thus, three ethics by Dasan including filial piety, admiration, and mercy could be recognized as the symbol of humanity. In other words, Dasan's three ethics in "Great Learning" can be recognized as the practical principles including educational issues and educational interactions. If these three ethics can be referred as the symbol of humanity as mentioned above, the implicit educational interactions are specifically constructed within the basic assumptions. Therefore, it is possible to clarify the specific ethics of practice by the indicating specific subjects and objects in the educational interactions between these three ethics of practice. Also, it helps more clear comprehension about the "Dàxuégōngyì大學公議, The Public debate of Great Learning", by Dasan.