• 식물병연구
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• 제8권4호
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• pp.215-219
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• 2002

2002년 7월 경남 통영시 광도면 석류재배 농가포장에서 열매가 부패되는 이상증상이 발생하였다. 분리된 병원균은 감자한천배지에서 균총의 색깔은 흰색이며 물결모양을 이루면서 왕성하게 자랐고, 배지상에서 분생포자각을 잘 형성하였다. 분생포자는 단세포이며 모양은 방추형이고, 색깔은 갈색 또는 올리브색이다. 크기는 10.3~17.4$\times$2.8~4.0 $\mu\textrm{m}$ 였다. 분생포자 형성 세포는 짧은 원통형이며 무색으로 크기는 12.4~1.4$\times$2.8~3.6 $\mu\textrm{m}$ 였다. 불생포자각의 모양은 구형이며 갈색으로, 각벽은 2~3세포이고, 크기는 124.6~228.4 $\mu\textrm{m}$ 였다. 균사생육 적온은 $25^{\circ}C$였다. 분리된 병원균을 건전한 석류에 유상, 무상접종한 결과 접종 3일 후 감염을 일으켰으며, 병원성이 강하였다. 이상과 같이 이 병원균을 Coniella granati에 의한 석류열매 썩음병으로 명명할 것을 제안한다.

• 한국항행학회논문지
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• 제22권5호
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• pp.420-428
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• 2018

본 논문은 태양광 발전시스템을 승압쵸퍼와 단상 펄스폭변조 전압형인버터를 사용하여 전원차단 경우나 전압변동 및 부하변동에 의한 출력전류 변화에도 일정한 출력전압을 유지하는 무정전 전원 공급장치(UPS)를 구성하였다. 본 시스템은 전압형인버터를 교류전원과 동기 시켜서 운전하고 정상상태에서는 전원으로부터 운전하고 정상상태에서는 전원으로부터 직류 측에 연결된 축전지를 태양전지를 이용한 광기전력효과와 함께 일정전압을 충전하며, 전원의 차단, 전원의 전압변동 및 부하전류의 변화에도 일정한 전압을 유지하도록 하였다. 에너지 저장장치 (ESS; energy storage system)를 상시 운영하여 공항의 기상 변화에 따른 파장별 LED 항공 유도신호 등을 효율적으로 운용하는 시스템을 구성 하였고, 전력절감효과를 얻을 수 있는 에너지절약 전원복합형 전력변환장치로 구성되어 있다. 출력은 PWM방식에 의하여 양호한 파형이 되도록 하고 전원차단과 부하의 상태의 변화 및 전원 전압 변동에도 일정한 전압으로 출력됨을 실험을 통하여 확인 할 수 있었다.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 추계국제학술대회
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• pp.159-159
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• 2003

Comet assay is a potential monitoring tool because DNA strand breakage may be produced by a wide range of agents. The comet assay, also called the single-cell gell electrophoresis (SCGE) assay, is rapid and sensitive method for the detection of DNA damage in cells. This study was performed for the identification of DNA damage in the cells from flounders and clams exposed to PAHs. As a control experiments, flounder and clam cells were exposed to $H_2O$$_2$. The cells exposed to $H_2O$$_2$ were displayed a typical nuclei movement DNA damage of cells were significantly increased when the isolated cells from the blood of flounders and the tissue of clams were in vitro exposed to the different concentrations (5, 10, 50, 100 ppb) of five kinds of PAHs (benzo[a]pyrene, pyrene, fluoranthene, anthrancene, and phenanthrene). For the in vivo test, flounders and clams were exposed to the different concentrations of BaP for 4 days. The results showed that DNA strand breakage was effected by the concentration of BaP and the duration of exposure. In high concentration of BaP, the mean tail lengths of nuclei was longer than it In low concentration, while the mean size of head DNA decreased. In this research, both in vitro and in vivo genotoxicity of PAHs could be biomonitored by the comet assay. Especially, clams and flounders seem to be useful as materials for monitoring genotoxic damage by comet assay.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.234-241
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• 1996

Two hundreds and thirty lactic acid bacteria, mostly isolated from Kimchi, including type strains were used for analysis of cellular fatty acids. The 230 test strains were recoverd in 7 major and 1 single clusters defined at Euclidian distance of 17.5. These aggregate taxa were equivalent to the genus Leuconostoc (aggregate group A, B, C and D), the genus Lactobacillus (aggregate group F), the genera Lactobacillus and Pediococcus (aggregate group E) and the genera Leuconostoc and Lactobacillus (aggregate group G). It is concluded as evident that FAMEs (Fatty Acid Methyl Esters) profile of cell can be used as a criterion in classification of lactic acid bacteria from kimchi. Additional comparative taxonomic studies need to be carried out on well chosen representative strains to determine the most appropriate methods of value.

• 한국가축번식학회지
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• 제21권3호
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• pp.287-292
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• 1997

This study was carried out to investigate the effects of concentration and kinds of cryoprotectants, equilibraction time, thawing temperature and time, sucrose concentration on the survival rates of frozen bovine demi-embryos. The bovine demi-embryos following dehydration by cryoprotectants a various concentration of sucrose were freezed by cell freezer and thawed in 3$0^{\circ}C$ water bath. Survival and in vitro developmental rates was defined as development rates on in vitro culture or FDA-test. The results are summarized as follows : 1. The high survival rates of demi-embryos after frozen-thawing in freezing medium was attained 2.0M glycerol. The high survival rates of demi-embryos after frozen-thawing in freezing medium was obtained using single cryoprotectant(25.0~30.0%) than mixed cryoprotectants(16.7~19.0%). 2. The survival rates of demi-embryos after frozen-thawing in freezing medium added 1.5M, 2.0M glycerol＋0.25M sucrose(37.5~33.3%) were higher survival rates than those of sucrose concentration of 0.50, 0.75M(12.5~26.7%). 3. The equilibration time on the survival rates of demi-embryos was attained after short period of time(30.0~35.0%) in the freezing medium higher than long period of time(21.1%). 4. The thawing temperature on the survival rates of demi-embryos was attained at 3$0^{\circ}C$ of thawing temperature(26.7~40.0%) higher than $25^{\circ}C$ or 37$^{\circ}C$ of thawing temperature(13.3~20.0%). 5. The thawing time on the survival rates of demi-embryos was attained at 1~5 minutes of thawing time(26.7~33.3%) in the freezing medium higher than 10 minutes of thawing time(13.3~18.8%).

• 한국해양환경ㆍ에너지학회지
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• 제9권4호
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• pp.187-192
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• 2006

조선소에서 배출되는 처리수, 혼합방류수 및 주변 하천수가 양식 생물에 미치는 생물 독성영향을 알아보기 위해 48시간 급성독성과 DNA 손상을 조사하였다. 조사대상 생물종으로는 조선소 주변에서 양식되고 있는 넙치, 조피볼락, 피조개, 멍게가 사용되었으며, 48 시간 노출 후 치사율을 파악하였고, DNA 손상 정도는 Comet assay을 이용하여 측정되었다. 급성독성 실험 결과, 넙치는 장평천에서 치사가 나타났고(26%), 조피볼락은 혼합방류수 1에서 치사가 나타났다(13%). 멍게는 고현천에서 10%의 치사율을 보였고, 피조개는 어느 시료에서도 치사가 나타나지 않았다. 본 연구에 사용되어진 어떠한 시료에서도 실험생물을 50%까지 치사시키는 독성이 나타나지 않아 $LC_{50}$은 계산될 수 없었다. 넙치는 장평천과 혼합방류수에서 대조구보다 유의하게 높은 DNA 손상을 보여주었고, 조피볼락은 장평천에서 유의하게 높은 DNA손상이 나타났다(p<0.05). 멍게는 세탁폐수에서 유의한 DNA손상이 나타났지만, 피조개에서는 모든 처리구에서 DNA 손상을 보이지 않았다. 치사율과 DNA 손상을 고려하였을 때 조선소의 처리수와 혼합방류수보다는 장평천에서 놀은 생물독성을 보여주는 것으로 나타났다.

• The Korean Journal of Physiology and Pharmacology
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• 제15권3호
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• pp.163-169
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• 2011

Corticosterone is known to modulate GABAergic synaptic transmission in the hypothalamic paraventricular nucleus. However, the underlying receptor mechanisms are largely unknown. In the anterior hypothalamic area (AHA), the sympathoinhibitory center that project GABAergic neurons onto the PVN, we examined the expression of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) of GABAergic neurons using intact GAD65-eGFP transgenic mice, and the effects of corticosterone on the burst firing using adrenalectomized transgenic mice. GR or MR immunoreactivity was detected from the subpopulations of GABAergic neurons in the AHA. The AHA GABAergic neurons expressed mRNA of GR (42%), MR (38%) or both (8%). In addition, in brain slices incubated with corticosterone together with RU486 (MR-dominant group), the proportion of neurons showing a burst firing pattern was significantly higher than those in the slices incubated with vehicle, corticosterone, or corticosterone with spironolactone (GR-dominant group; 64 vs. 11~14%, p<0.01 by $x^2$-test). Taken together, the results show that the corticosteroid receptors are expressed on the GABAergic neurons in the AHA, and can mediate the corticosteroid-induced plasticity in the firing pattern of these neurons. This study newly provides the experimental evidence for the direct glucocorticoid modulation of GABAergic neurons in the AHA in the vicinity of the PVN.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.152-152
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• 2003

As utilization of radiation in medicine, industry and biochemical research increases, the protection against radiation damage has become an important issue. Natural products such as herbal medicines are beginning to receive attention as modifiers on the radiation response. In the present study, the protective effect of a herb, Menthae Herba, against radiation-induced DNA damage was evaluated using alkaline single-cell gel electrophoresis (SCGE; comet assay) in the mouse peripheral blood Iymphocytes and the micronucleus formation test in the Chinese hamster ovary (CHO) cells. The tail moment, which was a marker of DNA damage in the SCGE, and the frequency of micronuclei was decreased in groups treated with Mentae Herba extract before exposure to 200 cGy of gamma-ray. We also confirmed its activities to scavenge DPPH and hydroxyl radicals. These experiments demonstrated that Menthae Herba was effective at reducing the radiation-induced damage of DNA and scavenging free radicals. It is plausible that scavenging of free radicals by Menthae Herba may have played an important role in providing the protection against the radiation-induced damage to the DNA. These results indicated that Menthae Herba might be a useful radioprotector and that radical scavenging appears to be one of the mechanisms of radiation protection.

• 한국수소및신에너지학회논문집
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• 제25권1호
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• pp.28-38
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• 2014

The organic-inorganic composite membrane in polymer exchange membrane fuel cells (PEMFCs) have several fascinating technological advantages such as a proton conductivity, thermal stability and mechanical properties. As the inorganic filler, silicon carbide (SiC) fiber have been used in various fields due to its unique properties such as thermal stability, conductivity, and tensile strength. In this study, composite membrane was successfully fabricated by modified-silicon carbide fiber. Modified process, as a novel process in SiC, takes reaction by phosphoric acid after oxidation process (generated homogeniusly $SiO_2$ layer on SiC fiber). The mechanical property which was conducted by tensile test of the 5wt% modified-$SiO_2@SiCf$ composite membrane was better than that of Aquivion casting membrane as well as ion cxchange capacity(IEC) and proton conductivity. In addition, the single cell performance was observed that the 5wt% modified-$SiO_2@SiCf$ composite membrane was approximately $0.2A/cm^2$ higher than that of a Aquivion casting electrolyte membrane and electrochemical impedance was improved with the charge transfer resistance and membrane resistance.

• 전력전자학회논문지
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• 제16권3호
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• pp.258-265
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• 2011

본 논문은 다이어프램의 공기압력을 제어하기 위한 가변 주파수 전류 제어기를 제안한다. 제안된 제어기는 기존의 다이어프램의 공기압력을 제어하는 방법과는 달리 단상 인버터를 이용하여 상 전류와 주파수를 제어한다. 한 상의 전류는 다이어프램의 지령 공기 압력을 추종하도록 조절되고, 전류 주파수는 기계적인 진동을 줄이기 위해 변화한다. 일정한 공기압력으로 부드럽게 변화하기 위해서 전류 주파수는 전류 제어기에서 제어전압에 따라 제어되며, 이 때의 상전류가 일정한 공기압력에 만족하게 되면 전류주파수는 다이어프램의 진동을 줄이기 위해 증가된다. 제어 전압에 의한 상 전류가 지령값보다 높게 되면 전류 주파수는 공기압력을 추종하기 위해 감소된다. 제안된 제어방식은 상용 다이어프램을 이용한 실험을 통해 확인하였다.