• ALGAE
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• 제22권3호
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• pp.235-240
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• 2007

The red tide-causing flagellate Chattonella anticfua can cause mass fish kills by their clogging in fish gills. Thisstudy examined the nutrient requirements of C. antiqua isolated from Korea. C. anticfua displayed maximum growthat the day five, followed by a decrease in cell density. Nitrate and nitrite were the preferred nitrogen sources, alonewith adenosine diphosphate for phosphorus compounds. In medium that contained ammonium, a significantdecrease in cell density was observed. Half-saturation constants, Ks, calculated from the maximum growth ratewere 4.94 U|M for NC>3 and 0.79 flM for P04. The growth of C. antiqua was not within the function of the N:P ratio (RU= 0.29). With an N:P ratio as low as 10, the increase in cell density was apparent, with a higher division rate. At lev-els above 50 fiM of NaNOg or 8 ;uM of NaHUPCU, the growth rates were somewhat decreased. Phosphate was thelimiting factor for C. antiqua growth since the starvation of phosphate had brought about a rapid decrease in celldensity in semi-continuous culture. Studies about the temporal modification of the efficiency of nitrate or phosphateuptake may be necessary to explain the bloom dynamics of C. antiaua.

• 수산해양교육연구
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• 제16권2호
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• pp.218-226
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• 2004

During the last two decades, the rapid increase in aquaculture world wide, particularly in finfish and shellfish culture, is the result of both area expansion and production intensification. Under these conditions, the prevalence and spread of infectious diseases have increased as a result of higher infection pressure and decreased resistance of the aquatic animals. Accordingly, the effective control of infectious diseases has become more and more important to development of aquaculture. Recently the Pathology Team of National Fisheries Research and Development(NFRDI), has played pivotal roles in establishing the national management and control system of aquatic animal health and disease by new legislative works and technical guidelines. Under the national aquatic animal disease control framework, the Pathology Team of NFRDI and MOMAF(Ministry of Maritime Affairs and Fisheries) should also establish effective management and regulations, with the support of enforcement and monitoring policies. In conjunction with effective aquatic disease national management, financial assistance or alternative compensation options for aquaculture should also be available in the event of production losses or eradication system.

• 한국게임학회 논문지
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• 제18권6호
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• pp.83-94
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• 2018

본 연구는 게임개발 성과를 효율적으로 향상시키기 위해 게임개발 조직의 특성이 게임성과에 미치는 영향을 살펴보고자 하였다. 게임개발 조직의 특성으로는 게임 프로젝트 관리 특성, PM 특성, 게임개발팀 특성, 조직문화로 구성하여 독립변수로 설정하였으며, 게임성과를 게임프로젝트 성과와 게임개발 최종성과로 나누어 종속변수로 설정하였다. 분석결과 4가지 게임개발 조직의 특성이 게임 프로젝트 성과 및 게임개발 최종 성과에 영향을 미치는 요인으로 나타났다. 본 연구를 통해 게임개발팀 내 구성원들의 역량을 제고하기 위해 게임개발에 집중할 수 있는 환경과 관리자들을 위한 적합한 매니지먼트 교육이 필요함을 시사하였다.

• 한국치위생학회지
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• 제20권6호
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• pp.925-936
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• 2020

Objectives: This study proposes a hypothetical model for job stress, job satisfaction, organizational commitment, and turnover intention through social exchange relations (LMX, TMX) and political skills (LPS) for dental hygienists working in dental clinics hygienists. Methods: A self-administrated questionnaire was administered from April 1 to May 12, 2020, with 171 dental clinic hygienists participating in Seoul, Busan and Gyeongnam. The data were analyzed using SPSS and AMOS statistical analysis programs. Results: First, in the hypotheses testing, a total of 7 of 18 hypotheses were supported. Second, the relatonship between leader-member exchange (LMX) or team-member exchange (TMX) and turnover intention, a full mediating effect of job stress or job satisfaction or organizational commitment on that exchange was found. However, the leader's political skills on the path to turnover intention were not statistically significant. Conclusions: It is considered that education to enhance job skills, support for leisure activities, and time to communicate opinions with each other should be provided to create an organizational culture that satisfies all members, thereby lowering the intention to turnover.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.335-339
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• 2011

The unique characteristics of the construction industry - such as the fragmentation of its processes, varied scope of works and diversity of its participants - are contributory factors to poor project performance. Several issues are unresolved due to the lack of a comprehensive technique to measure project outcomes including: inefficient decision making, insufficient communication, uncertain site conditions, a continuously changing environment, inharmonious working relationships, mismatched objectives within the project team and a blame culture. One approach to overcoming these problems appears to be to measure performance by gauging contractor satisfaction (Co-S) levels, but this has not been widely investigated as yet. Additionally, the key Co-S dimensions at the project level are still not fully identified. This paper concerns a study of satisfaction dimensions, primarily by a postal questionnaire survey of construction contractors registered by the Malaysian Construction Industry Development Board (CIDB). Eight satisfaction dimensions are identified that are significantly and substantially relate to these contractors - comprising: project cost performance, schedule performance, product performance, design satisfaction, site safety, project profitability, business performance and relationships between participants. -Each of these dimensions is accorded different priority levels of satisfaction by different contractors. The output of this study will be useful in raising the awareness and understanding of project teams regarding contractors' needs, mutual objectives and open communication to help to deliver a successful project.

• Journal of Pharmaceutical Investigation
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• 제38권3호
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• pp.183-189
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• 2008

The present study compared the feasibility of Caco-2 and MDCK cells as an efficient in-vitro model for the drug classification based on Biopharmaceutics Classification System (BCS) as well as an in-vitro model for drug interactions mediated by P-gp inhibition or P-gp induction. Thirteen model drugs were selected to cover BCS Class I{\sim}IV$ and their membrane permeability values were evaluated in both Caco-2 and MDCK cells. P-gp inhibition studies were conducted by using vinblastine and verapamil in MDCK cells. P-gp induction studies were also performed in MDCK cells using rifampin and the P-gp expression level was determined by western blot analysis. Compared to Caco-2 cells, MDCK cells required shorter period of time to culture cells before running the transport study. Both Caco-2 and MDCK cells exhibited the same rank order relationship between in-vitro permeability values and human permeability values of all tested model compounds, implying that those in-vitro models may be useful in the prediction of human permeability (rank order) of new chemical entities at the early drug discovery stage. However, in the case of BCS drug classification, Caco-2 cells appeared to be more suitable than MDCK cells. P-gp induction by rifampin was negligible in MDCK-cells while MDCK cells appeared to be feasible for P-gp inhibition studies. Taken all together, the present study suggests that Caco-2 cells might be more applicable to the BCS drug classification than MDCK-cells, although MDCK cells may provide some advantage in terms of capacity and speed in early ADME screening process.

• Journal of Nutrition and Health
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• 제39권8호
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• pp.742-747
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• 2006

This study was performed to investigate the lipolytic effects of Portulaca oleracea L. extract in 3T3-L1 adipocytes. The Portulaca oleracea L. was extracted with extrusion method using twin-screw extruder under $58{\sim}60rpm$ screw speed, $4{\sim}5kg/hr$ feed rate, $140^{\circ}C$ extrusion temperature. The lipolytic action of Portulaca oleracea L. extract was estimated by measuring the amount of glycerol and free fatty acids (FFA) released from 3T3-L1 adipocytes and by measuring the cellular lipid content in 3T3-L1 adipocytes. The hormone sensitive lipase (HSL) mRNA level was analyzed using quantitative real-time PCR. The Portulaca oleracea L. extract at 1 to $100{\mu}g/ml$ suppressed lipid accumulation. The release of glycerol and FFA into the medium, and the mRNA level of HSL were significantly increased by the addition of Portulaca oleracea L. extract at dose-dependent manner. In conclusion, the Portulaca oleracea L. extract was suggested to have the lipolytic effect through release of lipolytic products (FFA and glycerol) of triacylglyceride to the culture medium and suppression of lipid accumulation via up-regulation of HSL gene expression in 3T3-L1 adipocytes.

• Food Science and Biotechnology
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• 제18권2호
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• pp.500-505
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• 2009

The fibrinolytic enzyme, subtilisin D5, was purified from the culture supernatant of the isolated Bacillus amyloliquefaciens DJ-5. The molecular weight of subtilisin D5 was estimated to be 30 kDa. Subtilisin D5 was optimally active at pH 10.0 and $45^{\circ}C$. Subtilisin D5 had high degrading activity for the A$\alpha$-chain of human fibrinogen and hydrolyzed the $B{\beta}$-chain slowly, but did not affect the $\gamma$-chain, indicating that it is an $\alpha$-fibrinogenase. Subtilisin D5 was completely inhibited by phenylmethylsulfonyl fluoride, indicating that it belongs to the serine protease. The specific activity (F/C, fibrinolytic/caseinolytic activity) of subtilisin D5 was 2.37 and 3.52 times higher than those of subtilisin BPN' and Carlsberg, respectively. Subtilisin D5 exhibited high specificity for Meo-Suc-Arg-Pro-Tyr-pNA (S-2586), a synthetic chromogenic substrate for chymotrypsin. The first 15 amino acid residues of the N-terminal sequence of subtilisin D5 are AQSVPYGISQIKAPA; this sequence is identical to that of subtilisin NAT and subtilisin E.

• 대한본초학회지
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• 제23권3호
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• pp.11-18
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• 2008

SunBangHwalMyungEum (SBH) has the effects of subduing swelling, resolving masses and alleviating pain in traditional oriental medicine. Recent studies showed that SunBangHwalMyungEum produced anti-cancer, anti-metastasis and immuno-modulatory effects. However there is lack of studies regarding the effects of SBH on the immunological activities. The present study was conducted to evaluate the effect of SBH on the regulatory mechanism of cytokines and nitric oxide (NO) in Raw 264.7 cells. Methods : After the treatment of SBH, cell viability was measured by MTT assay, NO production was monitored by measuring the nitrite content in culture medium. Inducible nitric oxide synthase (iNOS) was determined by immunoblot analysis, and levels of cytokine were analyzed by sandwich immunoassays. Results : Results provided evidence that SBH inhibited the production of NO, iNOS, $interleukin-1{\beta}$ ($(IL-1{\beta})$), IL-6, and the activation of phospholylation of inhibitor ${\kappa}B{\alpha}$ in Raw 264.7 cells activated with lipopolysaccharide. Conclusions : These findings suggest that SBH can produce anti-inflammatory effect, which may play a role in adjunctive therapy in Gram-negative bacterial infections.

• 해양환경안전학회지
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• 제25권7호
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• pp.858-866
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• 2019

해운산업구조의 변화에 따라 다양한 국적의 선원을 자국민 선원과 함께 승선시키는 혼승선박이 증가하고 있다. 선상 업무의 특성과 함께 혼승에 따른 문화가 형성되고 이는 선내 생활환경의 변화를 초래하여 의사소통의 문제, 교육훈련의 부족 등 다양한 문제점을 야기하고 있다. 본 연구에서는 혼승에 따른 문제점을 파악하고 해결하기 위해 외항선 외국인선원 입국 후 교육의 체계화를 위한 방안을 제시하였다. 다양한 규모의 선사에서 외국인선원의 인사 관련 업무를 담당하고 있는 인원을 대상으로 설문을 실시하고 IBM SPSS Statistic 26 프로그램을 사용하여 설문 결과를 분석하였다. 설문 조사 결과에 따라 외국인선원 교육형태, 교육방법, 문제점 등을 파악하고 이를 기반으로 관련 교육의 체계화를 통해 문제점을 해결할 3가지 개선방안을 제시하였다.