• 한국식품저장유통학회지
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• 제12권6호
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• pp.643-649
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• 2005

전통발효식품인 된장으로부터 높은 활성의 fibrinolytic enzyme를 생산하는 미생물을 수십 종 분리하였다. 산업적으로 우수한 균종을 선별하기 위하여 분리된 미생물중 fibrinolytic enzyme활성과 성장 속도면에서 가장 우수한 균주를 선별하여 하였으며, 형태학적, 생화학적 및 생리학적 특성을 조사한 후 Bacillus sp.로 동정되었다. Fibrinolytic enzyme생산을 위한 최적 배양조건은 초기 pH $6\~8$일 때 상대활성도가 $80\%$이상을 나타내었고, 배양 12시간째에 가장 높은 활성도를 나타내었다. Fibrin plate를 이용한 혈전용해능을 확인한 결과 높은 혈전용해능을 가지고 있었다. 탄소원으로 galactose를 $4\%$ 첨가 하였을 때 가장 우수하였으며, 질소원은 malt extract를 $4\%$ 첨가 하였을 때 가장 우수하였다. 무기염은 $K_2HPO_4$를 첨가하였을 때 가장 우수한 활성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.226-231
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• 2006

Several white-rot fungi are able to produce extracellular lignin-degrading enzymes such as manganese peroxidase (MnP), lignin peroxidase (LiP), and laccase. In order to enhance the production of laccase and MnP using Trametes versicolor KCTC 16781 in suspension culture, the effects of major medium ingredients, such as carbon and nitrogen sources, on the production of the enzymes were investigated. The decolorization mechanism in terms of biodegradation and biosorption was also investigated. Among the carbon sources used, glucose showed the highest potential for the production of laccase and MnP. Ammonium tartrate was a good nitrogen source for the enzyme production. No significant difference in the laccase production was observed, when glucose concentration was varied between 5 g/l and 30 g/l. As the concentration of nitrogen source increased, a lower MnP activity was observed. The optimal C/N ratio was 25 for the production of laccase and MnP. When the concentrations of glucose and ammonium tartrate were simultaneously increased, the laccase and MnP activities increased dramatically. The maximum laccase and MnP activities were 33.7 U/ml at 72 h and 475 U/ml at 96 h, respectively, in the optimal condition. In this condition, over 90% decolorization efficiency was observed.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.78-78
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• 1995

Increasing evidence indicates that the production of nitric oxide (NO) by inducible NO synthase (NOS) is tightely regulated. Transforming growth factor-${\beta}$ (TGF-${\beta}$) is a homodimeric protein secreted during macrophage activation, but several lines of evidence suggest that TGF-${\beta}$ is selectively suppressive for macrophage NO production. We therefore reasoned that a strategy employing oligodeoxynucleotides(ODNs) complemently to TGF-${\beta}$ mRNA (antisense ODNs) might increase NO production in IFN-${\gamma}$-treated murine peritoneal macrophages. To evaluate this concept, we tested the effects of antisense ODNs targeted to TGF-${\beta}$ mRNA (25-mer ODNs complemently to TGF-${\beta}$mRNA sequences) by introducing it into the medium of cultured macrophages. Phosphorothiolation of ODNs were employed to retard their degradation. Antisense ODNs had no effect on NO production by itself, whereas IFN-${\gamma}$ alone had modest effect. When antisense ODNs were used in combination with IFN-${\gamma}$, there was a marked cooperative induction of NO production, These effects of antisense ODNs were associated with decreased TGF-${\beta}$ expression in activated macrophages. ODNs with the same nucleotides but a scrambled sequence had no effect. Adding anti-TGF-${\beta}$ antibodies to the IFN-${\gamma}$-treated macrophages mimicked the positive effect of antisense ODNs on NO production. In addition, the effects of either antisense ODNs or anti-TGF-${\beta}$ antibodies were blocked by adding TGF-${\beta}$ in cultured macrophages. These results indicate that the generation of TGF-${\beta}$ by activated macrophages provides a self-regulating mechanism by which the temporal and perhaps spatial production of NO, a reactive and potentially toxic mediator, can be finely regulated.

• 디지털융복합연구
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• 제14권6호
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• pp.85-91
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• 2016

최근의 여러 연구는 럭셔리 브랜드가 자선과 결부될 때 긍정적으로 나타나는 소비자 반응의 기저에 죄책감 감소가 있음을 밝혔다. 본 연구는 더 나아가 럭셔리 브랜드가 부정적인 경영활동을 통해 이윤을 취함을 소비자가 알때, 럭셔리 브랜드가 자선활동을 하거나 하지 않음에 따라 죄책감 감소의 영향이 달라지며, 이로 인해 소비자의 구매의도도 상이하게 나타남을 보이고자 하였다. 2(자선활동 연계 여부) x 2(생산방식 지각: 부정 vs. 통제) 피험자 간 설계로 진행된 실험 결과, 럭셔리 브랜드의 자선 연계는 제품 구매의도에 긍정적으로 영향을 미쳤으며, 제품 생산방식이 부정적이라고 지각한 경우 그렇지 않을 때보다 구매의도가 낮았다. 그런데 자선 연계가 구매의도에 미치는 영향은 제품 생산방식의 지각에 의해 조절되었는데, 자선 연계가 되어있을 때의 지각의 차이가 미치는 영향이 자선 연계가 없을 때의 지각의 차이가 미치는 영향보다 큰 것으로 나타났다. 한편 자선 연계 여부가 구매의도에 미치는 영향 및 자선 연계 여부와 생산방식 지각의 상호작용이 구매의도에 미치는 영향 모두 죄책감 감소에 의해 매개되는 것으로 나타났다. 본 연구는 럭셔리 브랜드 제품의 자선연계에 있어 소비자가 제품 생산 방식의 윤리성을 어떻게 지각하는 지가 중요한 요인이 될 수 있음을 밝혔다는 데 학문적 및 실무적으로 기여하고 있다.

• 한국축산식품학회지
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• 제24권3호
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• pp.303-309
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• 2004

Conjugated linoleic acid (CLA) is currently under intensive investigation due to its health benefits. A great deal of interest has been paid to the possible health-promoting roles of CLA, but there are not many studies available on the mechanism of CLA production by ruminal microorganisms. CLA is produced as an intermediate of the characteristic biohydrogenation process of linoleic acid(LA) in the rumen and its production has direct relationship to numerous environmental factors including particle association, substrate concentration, forage-to-grain ratio, pH, ionopore, bacterial cell density, etc. Some of these factors were known to affect hydrogenating activities of Butyrivibrio fibrisolvens A38 which is an active rumen bacterium in CLA production. Dairy cow is a main source of CLA, and its level could be increased by dietary manipulation changing the physiological environment of rumen bacteria such as B. fibrisolvens A38. Therefore, the effects of various factors on. ruminal biohydrogenation should be carefully considered to optimize not only CLA production, but also other fatty acid metabolism, both of which are directly affecting nutritional quality and functionality of dairy products. In this review, the relationship between various environmental factors and ruminal CLA production is discussed focusing on the CLA production of B. fibrisolvens A38.

• Journal of Welding and Joining
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• 제14권1호
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• pp.99-106
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• 1996

Development of an automatic TIG welding system incorporating a vision sensor and torch control mechanism leads to an improved welding quality and greater production efficiency. The automatic welding system should be greatly restricted in its size and weight for the LNG(Liquefied Natural Gas) storage tank and also provide a unique torch rotating mechanism which keeps the torch tip in the constant position while the angle is changed continuously to maintain the welding torch substantially perpendicular to the weld line. The developed system is driven by two translation axes X, Z and one rotational axis. A moving line window method is adopted to the image recognition of the corrugated membranes with specular reflection. This method decides original laser stripe patterns in image which is affected by multi-reflection. A self-teaching algorithm, which guides the automatic welding machine with the information provided by the CCD camera without any previous learning of a reference trajectory, was developed for tracking the corrugated membrane of the LNG tank along the weld line.

• International Journal of Precision Engineering and Manufacturing
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• 제2권1호
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• pp.43-55
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• 2001

A continuously variable transmission(CVT) mechanism composed of one differential gear unit and one continuously variable unit(CVU) can be classified according to the coupling of CVU and the direction of power flows. The mechanism has many advantages which are the decrease of CVT size, the increase of overall efficiency, the extension of speed ratio range and generation of geared neutral. The CVT mechanism considered here is the input coupled type which combines the functions of a 2K-H I type differential gear unit and a V-belt type CVU. One shaft of the CVU is connected directly to the input shaft and another shaft of it is linked to the differential gear unit. It is shown that some fundamental relations(speed ratios, power flows and efficiencies) for twelve mechanisms previously described are valid by various experimental studies, six of them produce a power circulation and the others produce a power split. Some useful comparisons between theoretical analysis and experimental results are presented. General properties also are discussed, which connect following power flow modes : (a) power circulation mode; (b) power split mode.

• The Plant Pathology Journal
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• 제25권4호
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• pp.389-399
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• 2009

A group of beneficial plant bacteria has been shown to increase crop growth referring to as plant growth-promoting rhizobacteria (PGPR). PGPR can decrease plant disease directly, through the production of antagonistic compounds, and indirectly, through the elicitation of a plant defense response termed induced systemic resistance (ISR). While the mechanism of PGPR-elicited ISR has been studied extensively in the model plant Arabidopsis, it is less well characterized in crop plants such as pepper. In an effort to better understand the mechanism of ISR in crop plants, we investigated the induction of ISR by Bacillus cereus strain BS107 against Xanthomonas axonopodis pv. vesicatoria in pepper leaves. We focused on the priming effect of B. cereus strain BS107 on plant defense genes as an ISR mechanism. Of ten known pepper defense genes that were previously reported to be involved in pathogen defense signaling, the expression of Capsicum annum pathogenesis-protein 4 and CaPR1 was systemically primed by the application of strain BS107 onto pepper roots confirming by quantitative-reverse transcriptase PCR. Our results provide novel genetic evidence of the priming effect of a rhizobacterium on the expression of pepper defense genes involved in ISR.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.208-219
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• 2000

In this study, static axial crush tests were performed with the new aluminum/GFRP hybrid tube. Glass/Epoxy prepregs were wrapped around an aluminum tube and co-cured. The failure of the hybrid tube was stable and progressive without trigger mechanism, and specific energy absorption was increased to the maximum of 33% in comparison with the aluminum tube. Effective energy absorption is possible for an inner aluminum tube because a wrapped composite tube constrains the deflection of an aluminum tube. The failure of a hybrid composite tube was stable without trigger mechanism because the inner aluminum tube could play the role of the crack initiator and controller. Mean crushing load could be calculated by modifying the plastic hinge collapse model for hybrid materials. The predicted results by this analytical model showed good agreement with the experimental results. It can be said that Aluminum/Glass-Epoxy hybrid tube is suitable for the vehicle front structure because this hybrid tube shows effective energy absorption, easy production, and simple application capability for RTM process.

• 약학회지
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• 제56권2호
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• pp.80-85
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• 2012

Previously, we have reported that arachidonic acid (AA) appears to be involved in the induction of apoptosis in HepG2 human hepatoblastoma cells. In this study we investigated the possible role of the NADPH oxidase, a membranebound enzyme generating reactive oxygen species (ROS), in the mechanism of AA-induced apoptosis in HepG2 cells. Apoptotic cell death induced by AA was significantly suppressed by various inhibitors of the NADPH oxidase, diphenylene iodonium (DPI), apocynin (Apo) and neopterine (NP). In addition, these inhibitors of the NADPH oxidase completely blunted the AA-induced ROS elevation. Next, we investigated the implication of metabolic pathway of AA in these AA actions. Both apoptosis and ROS production induced by AA were not significantly altered by treatment with indomethacin (Indo) or nordihydroguaiaretic acid (NDGA), selective inhibitors of cyclooxygenase (COX) and lipoxygenase (LOX), respectively, suggesting that AA metabolites produced by COX or LOX may not have an essential role in the AA-induced apoptosis and ROS generation. Collectively, these results suggest that the NADPH oxidase may be a key player in the mechanism of AA-induced apoptosis in HepG2 cells. These results further suggest that NADPH oxidase may be a good target for the management of human hepatomas.