• 한국가축번식학회지
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• 제27권4호
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• pp.309-315
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• 2003

DNA methylation at CpG sites, which is a epigenetic modification, is associated with gene expression without change of DNA sequences. During early mouse embryogenesis, dynamic changes of DNA methylation occur. In this study, DNA methylation patterns of porcine embryos produced in vivo and in vitro were examined at various developmental stages by the immunocytochemical staining method. Interestingly, active demethylation was not observed on the paternal pronucleus of porcine zygotes. However, differences were detected in the passive demethylation process between in vivo and in vitro embryos. There was no change in the DNA methylation state until the blastocyst stage of in vivo embryos, whereas partial demethylation was observed in several blastomeres from a 4 cell stage to a morula stage of in vitro embryos. The whole genome of inner cell mass (ICM) and trophectoderm (TE) cells in porcine blastocysts were evenly methylated without de novo methylation. Our findings demonstrate that genome-wide demethylation does not occur in pig embryos during preimplantation development unlike murine and bovine embryos. It indicates that the machinery regulating epigenetic reprogramming may be different between species.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.500-503
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• 2007

During the COMS system level test, the RF compatibility will be performed in order to verify that there is no issue in RF interface between satellite and COMS ground station, namely SOC (Satellite Operation Center) before the launch. As used for KOMPSAT1, the RF coaxial cable was chosen to be used to connect satellite and SOC with various advantages as compared with ground antennas. As the preparation step, RF cable and required multiplexer were tested in advance. This paper suggests the way for the RF compatibility tests between the satellite and the SOC over RF cable interface and presents the estimated level diagram as the signal power analysis result.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2007년도 6th OSONG INTERNATIONAL BIO-SYMPOSIUM
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• pp.241.1-241.1
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• 2007

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.247-247
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• 2005

• Fisheries and Aquatic Sciences
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• 제1권2호
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• pp.159-167
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• 1998

The environmental characteristics in shellfish farms were investigated in the western part of Jinhae Bay, 1996. During summer, anoxia and high nutrient concentrations were found in the bottom waters of shellfish farms. The concentrations of particulate organic species in seawaters were enriched, showing an average 57.44 uM for POC, an average 5.45 uM for PON, and an average 0.42uM for PP. The sediments environment in the farms was very polluted. The concentrations of COD and AVS were more than 20 mg/g.dry and 0.5 mg/g.dry, respectively. The total sedimentation rate was high as an average $7.81g/m^2/day$ with organic matter contents of $26\%$. Oxygen consumption rate was similar to polluted area as an average of $439mg/m^2/day$. Nutrient release rates were an average of $8.25mg/m^2/day$ for nitrogen and an average of $1.38mg/m^2/day$ for phosphorous. The cluster analysis through environmental data in summer indicated that DO, nutrient in the bottom water, and AVS in the sediment were important factors to characterize the polluted environmental site.

• 공학교육연구
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• 제17권5호
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• pp.33-40
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• 2014

This study aimed to analyze the current trends and future issues of the creativity development research in the Korean engineering education. The analysis led to categorizing the previous research topics into the following five domains: (i)systems and media (ii)instructional strategies and methodologies (iii)curriculum (iv)evaluation and (v) learner characteristics. The analysis further deduced more detailed sub-domains from each of the five domains. In addition, this study investigated publication frequencies of each domain and sub-domains and grasped specific flows of past research topics. Finally, based upon the analysis, this study drew implications and ramifications for creativity development studies in the Korean engineering education, elucidated future issues and refined upcoming research agendas. It is hoped that this research will articulate the present status of the studies that deal with creative education catering to engineering students and help set paths for future research.

• Journal of Animal Science and Technology
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• 제63권6호
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• pp.1301-1313
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• 2021

This study investigated the effects of applying cellulase and starch on the fermentation characteristics and microbial communities of Napier grass silage after ensiling for 30 d. Three groups were studied: No additives (control); added cellulase (Group 1); and added cellulase and starch (Group 2). The results showed that the addition of cellulase and starch decreased the crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and pH significantly (p < 0.05) and increased water-soluble carbohydrate (WSC) content (p < 0.05). The addition of additives in two treated groups exerted a positive effect on the lactic acid (LA) content, lactic acid bacteria (LAB) population, and lactic acid / acetic acid (LA/AA) ratio, even the changes were not significant (p > 0.05). Calculation of Flieg's scores indicated that cellulase application increased silage quality to some extent, while the application of cellulase and starch together significantly improved fermentation (p < 0.05). Compared with the control, both additive groups showed increased microbial diversity after ensiling with an abundance of favorable bacteria including Firmicutes and Weissella, and the bacteria including Proteobacteria, Bacteroidetes, Acinetobacter increased as well. For alpha diversity analysis, the combined application of cellulase and starch in Group 2 gave significant increases in all indices (p < 0.05). The study demonstrated that the application of cellulase and starch can increase the quality of Napier grass preserved as silage.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.72-78
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• 1998

The larvae of Balanus improvisus were reared in the laboratory from hatching to cyprid. Larval development consists of six nauplius stages and a cyprid. Morphological features of all the nauplius stages are illustrated and described.

• Genomics & Informatics
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• 제19권4호
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• pp.39.1-39.8
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• 2021

Tamoxifen (TAM) is an anticancer drug used to treat estrogen receptor (ER)-positive breast cancer. However, its ER-independent cytotoxic and antifungal activities have prompted debates on its mechanism of action. To achieve a better understanding of the ER-independent antifungal action mechanisms of TAM, we systematically identified TAM-sensitive genes through microarray screening of the heterozygous gene deletion library in fission yeast (Schizosaccharomyces pombe). Secondary confirmation was followed by a spotting assay, finally yielding 13 TAM-sensitive genes under the drug-induced haploinsufficient condition. For these 13 TAM-sensitive genes, we conducted a comparative analysis of their Gene Ontology (GO) 'biological process' terms identified from other genome-wide screenings of the budding yeast deletion library and the MCF7 breast cancer cell line. Several TAM-sensitive genes overlapped between the yeast strains and MCF7 in GO terms including 'cell cycle' (cdc2, rik1, pas1, and leo1), 'signaling' (sck2, oga1, and cki3), and 'vesicle-mediated transport' (SPCC126.08c, vps54, sec72, and tvp15), suggesting their roles in the ER-independent cytotoxic effects of TAM. We recently reported that the cki3 gene with the 'signaling' GO term was related to the ER-independent antifungal action mechanisms of TAM in yeast. In this study, we report that haploinsufficiency of the essential vps54 gene, which encodes the GARP complex subunit, significantly aggravated TAM sensitivity and led to an enlarged vesicle structure in comparison with the SP286 control strain. These results strongly suggest that the vesicle-mediated transport process might be another action mechanism of the ER-independent antifungal or cytotoxic effects of TAM.

• 농업과학연구
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• 제46권3호
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• pp.653-660
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• 2019

Ganoderma lucidum, an oriental polypore fungus and medicinal mushroom, has a long history of use for promoting health and longevity in Korea, China, and other Asian countries. This study was aimed at determining the anti-inflammatory activity and mechanism of action of Ganoderma lucidum in murine macrophage RAW 264.7 cells. Ganoderma lucidum was extracted with ethanol and freeze-dried. The anti-inflammatory effect (nitrite production) of Ganoderma lucidum extracts was tested using a nitric oxide (NO) colorimetric assay. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) was performed to quantify the mRNA expression of cytokines including tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6. Western blotting was performed to measure the expression levels of inflammation-related proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor kappa B ($NF-{\kappa}B$) p65, and phosphorylated $NF-{\kappa}B$ p65. The NO colorimetric assay showed that NO production increased with the treatment of lipopolysaccharide in (LPS)-activated RAW 264.7 macrophages and decreased with the cotreatment of Ganoderma lucidum extracts and LPS. Ganoderma lucidum extracts repressed the mRNA expressions of cytokines, which were increased after the LPS treatment. In addition, Ganoderma lucidum extracts inhibited the LPS-induced expression of iNOS and COX-2 and the LPS-induced phosphorylation of $NF-{\kappa}B$ p65. These results suggest that the Ganoderma lucidum extracts exert an anti-inflammatory activity by inhibiting $NF-{\kappa}B$ related proteins and cytokines.