• Korean Journal of Microbiology
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• v.36 no.3
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• pp.236-241
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• 2000

A defensin is an inducible antibacterial peptide from a fleshfly and contains 40 residues basic peptide with six cysteines. For the consiruction of recombinant S cerevisiae expressing defensin, the structural gene coding for active defensin was chemically synthesized and fused in fiam to GAP promoter, MFul preprosequence and the GAL7 transcription terminator, generating a recombinant plasnlid pGMD18. S. ce~evisine 2805 Gells were transror~ned to uracil prototroph by the pGMDl8 arid the transformed cells showing antibacterial activity against 111. luteus TAM1056 were selected by growth inhibition zone assay. The optimal culture conditions for the unprovement of the defensin production of a selected tmdonnant were investigated. The optirmzed medium containing 0.4% yeast extract, 2% corn steep liquor, 2.5% glucose and 0.05% $C_2CO_3$, could be determined and the optimum lemperature. and initial pH could be detennnied as $28^{\circ}C$ and pH 3, ~mpectively. The optimized conditioiis revealed the trvofold Increase in the cell growth and the fourfold in the antibaclerial activity. coinpar-ed with tllc Yl'D medium.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.409-441
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• 2018

This study is a case study about the Valero Energy Corporation, the largest American independent refinery company, examining the characteristics of human resource management as a union avoidance strategy. The main research questions here are whether union substitution strategy differs clearly from union suppression strategy in the context of Valero Energy. Since the establishment in 1980, the Valero had maintained non-union tradition. The typical examples of human resource management in the non-unionized American companies are easily found in the Valero, such as strong CEO leadership, manpower policy emphasizing corporate culture and teamwork, direct communication between company and individual employees, no lay-off policy and no outsourcing policy of HRM, salary level around average of industry and best level of fringe benefits in the industry, non-union tradition and well-functioned alternative dispute resolution system and so on. Until now, based on tremendous growth and profitability, the company have applied union substitution method adopted by good companies as concrete method of union avoidance strategy instead of union suppression method that marginal enterprise prefers.

• The Mathematical Education
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• v.37 no.1
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• pp.35-54
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• 1998

Half century has passed since Korean peninsula was divided into South and North Korea. Now a days, there are many differences of politics, economy, culture and education between South and North Korea. Especially mathematics education in which I am interested has a lot of changes and differences. This is proved true by defects' proof. For those reasons, I compared South Korea's education ideology, goal and system, and goals of mathematics education with North Korea's. I compared geometric(1-4 years, published by Pyong-yang Educational Book Publication Co. 1991) of mathematics texts(1-6 years) which are used in the secondary school with mathematics text of South Korea in contents and organization of them. As a result of this comparison, education ideology and goal are distinctly different from those of South Korea because of the difference of pursuing humanity. In North Korea, the curriculum is very strict without autonomy. There are 1283 mathematics classes which are occupied 19% for six years during the secondary school. The contents are very similar, but there is a little difference in the definition of a term. The problems which praise Kim Il-sung and his son and reveal loyalty to them were found, and there were a lot of problems in order to promote hostile feeling against U.S.A and South Korea, too. In conclusion, mathematics education of Korean peninsula should be reunified in the fields of the terms and contents at first.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.353-357
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• 2008

A series of studies has been conducted to establish a base infrastructure for an ovarian follicle culture system in the porcine and this study was designed to develop an effective retrieval protocol of preantral follicles. Five different methods using collagenase type I (A) or IV (B, C1, C2 and C3), which employed different treatment durations and/or conditions, were employed and sliced ovarian tissue of prepubertal gilts was provided for the retrieval. A significant increase in total number of follicles retrieved was detected when collagenase IV (methods B or C) was used. In total, more ovarian follicles were retrieved by method B undertaking agitation and method C2 without the agitation than method C1 and C3, while the number of preantral follicles collected was the largest in method B. Neither incubation in 5% $CO_2$ in air atmosphere instead of the agitation nor increased duration of enzymatic treatment up to 120 minutes improved the efficiency of follicle retrieval. There were no differences in the number of follicles retrieved from intact ovaries and from used ovaries for oocyte collection. These results demonstrate the collagenase IV treatment with agitation is effective for retrieving porcine preantral follicles from the ovaries.

• Journal of Biosystems Engineering
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• v.24 no.6
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• pp.487-492
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• 1999

One of effective utilization method of rice husk is to utilize it as culture material by carbonizing the rice husk. As a second part of a series to investigate the effective and continuous production of carbonized rice husk by a cyclone combustor, a non-slagging vertical cyclone combustor without vortex collector pocket was introduced. Isothermal and mixed firing with LPG and rice husk were undertaken in order to characterize the system. Inert rice husk was used during the isothermal test to find mass of rice husk collected. It was impossible to ignite rice husk itself over the experimental conditions considered in this experiment. Cyclone combustor was operated at temperatures of 1,273~1,473K. Detailed combustion data were obtained from a pilot unit with the air flow rate of 70m$^3$/h and rice husk feed of 2kg. The equivalence ratio ranged from 0.66 to 3.48. The auxiliary gas flow rate was varied from 3.22 to 12.86$\ell$/min. The weight reduction, pH and particle size distribution of carbonized rice husk were measured to evaluate the quality of carbonized rice husk. An analysis of exhaust gas emission was conducted to characterize the combustor. The required carbonized rice husk could be obtained at equivalence ratio of 1.68~2.17, combustor temperature of 1,273~1,373K and auxiliary gas flow rate of 3.22~6.43$\ell$/min. A method to reduce CO emissions should be employed.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2190-2199
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• 2009

Nihombashi is located in the central area of Tokyo, Japan. Tokyo has been the capital in Japan since the Edo period, which started approximately 400 years ago, and has accepted a variety of cultures, human resources, businesses for the last 400 years. This has resulted in building up the present prosperity. The Sumida River, one of the symbols of Tokyo and its tributaries including the Kanda River and the Nihombashi River, flows through the Nihombashi district. The river and tributaries used to benefit to the City of Edo. Due to the economic development and the industrial growth in Tokyo, however, they were polluted and lost their functions. In 1960s, approximately 40 years ago, the Sumida River became so dirty that local citizens kept away from it. The Nihombashi River was covered with an expressway, which was obscuring the river view. Since 1970s, local communities have proposed to rehabilitate rivers in Tokyo successively, and have proceeded with measures for river floods, improvement of sewage systems and construction of water purification facilities. Consequently, the quality of the river water was considerably improved in 1990. The stagnant rivers were turned into ones that local citizens were physically able to come close by. Today, restoring of the environment and the appearance of the city in the old days, Nihombashi district has been proposed as a model city of the future, which is alive with history and culture and harmonizing with rivers. The concept is "To Create, To Reserve, To Restore." This paper introduces a case study of the urban development, in which the local communities and public authorities collaborated with and proposed a brand-new style of the urban city harmonizing with the environment.

• Journal of Embryo Transfer
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• v.9 no.3
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• pp.269-277
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• 1994

The objective of this study was to develop an effective in vitro production system capable of obtaining more porcine embryos from immature oocytes These experiments were conducted to examine the effect of sperm factor on the IVF and IVD, and the effect of coculture with somatic cells on the IVD of embryos. Although the concentration of epididymal sperm for IVF did not affect on cleavage rate, but 5 x 105 sperm/mi showed the highest cleavage rate(48.7%) and the developmental potential of IVF oocytes from this concentration was also greatly higher (P$^{\circ}C$-stored sperm for l2hrs and the cleavage rate from fresh sperm was significantly higher (P<0.05) than that from frozen sperm, but the developmental potential after IVF was slightly high from the frozen sperm. The cleavage rate of IVF oocytes cocultured with oviductal epithelial cells and cumulus cells was 76.3% and 72.9%, respectively. There was no difference between two coculture systems but this rate was significantly higher(P<0.05) than that of medium alone(42.0%).

• BMB Reports
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• v.43 no.10
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• pp.688-692
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• 2010

In a previous study, we recently claimed that dihydrotestosterone (DHT)-inducible dickkopf-1 (DKK-1) expression is one of the key factors involved in androgen-potentiated balding. We also demonstrated that L-ascorbic acid 2-phosphate (Asc 2-P) represses DHT-induced DKK-1 expression in cultured dermal papilla cells (DPCs). Here, we investigated whether or not L-threonate could attenuate DHT-induced DKK-1 expression. We observed via RT-PCR analysis and enzyme-linked immunosorbent assay that DHT-induced DKK-1 expression was attenuated in the presence of L-threonate. We also found that DHT-induced activation of DKK-1 promoter activity was significantly repressed by L-threonate. Moreover, a co-culture system featuring outer root sheath (ORS) keratinocytes and DPCs showed that DHT inhibited the growth of ORS cells, which was then significantly reversed by L-threonate. Collectively, these results indicate that L-threonate inhibited DKK-1 expression in DPCs and therefore is a good treatment for the prevention of androgen-driven balding.

• Journal of Korean Society of Rural Planning
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• v.14 no.3
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• pp.99-110
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• 2008

Tourist destination remodeling project is the tourist destination activation program to promote underdeveloped tourist destination that the Ministry of Culture and Sports has been implementing as a pilot program since 2005. Since previous tourist destination development programs focused on developing facilities, they could not quite cope with the changes in the tourism paradigm. Especially for caves, they could not escape from the simple sightseeing for the characteristics of the resource were fit to the caves. These results failed to meet tourist demands to experience and participate that the number of tourists is continuously decreasing. To cope with the circumstances, the government introduced a pilot program, a comprehensive tourist destination reorganization plan designed to comprehensively promote the tourism contents development (software) that can differentiate the region such as the tourism activation programs, tourist destination management and operation system reorganization (humanware) along with the repair of facilities (hardware project). This study emphasized the participation of residents who are the actual subject of management and operation of tourist facilities and programs in the course of establishing the master plan for remodeling for Gossi Cave that it can be used as the reference for establishing remodeling plan based on resident participation in the future.

• YAKHAK HOEJI
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• v.38 no.2
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• pp.158-165
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• 1994

A protein-polysaccaride fraction Kp(53.9% polysaccharide, 14.2% protein) was separated from the shake-cultured mycelia of a basidiomycetous fungus, Phellinus linteus, and its antitumor activity against sarcoma 180 in ICR mice was investigated. When administered after the tumor implantation, Kp exerted antitumor activity by inhibiting the growth of the sarcoma 180 solid tumor by 71.5% and increasing the life span of the sarcoma 180 ascitic mice by 51.5% at 100 mg/kg. In pretreatment tests, in which Kp was administered once daily for 9 days before the tumor implantation, Kp inhibited the growth of the solid and ascites form of sarcoma 180, respectively, by 35.4% and by 80.3% at 100 mg/kg. However, Kp showed no in vitro cytotoxic activity against a murine leukemia L1210 and a human gastric tumor SNU.1 upto the concentration of $200\;{\mu}g/ml$. From these results, it is clear that the antitumor activity of Kp is exerted through its immunomodulating activity on the host's immune system.