• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.122-127
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• 2007

In this study, an analytical method was optimized for detecting dioxin-like PCBs in fish and shellfish. Here, homogenized samples were extracted using an accelerated solvent extraction (ASE) system with 33 mL cell size. Multilayer column chromatography, which consisted of acidic, basic and neutral silica gels, was used for the clean up of the extracts. The instrumental analysis was executed by HRGC/HRMS to a resolution of 10,000 using 4 window multiple ion detection (MID) mode. For the results, the average recoveries ranged from 94.1 to 104.1% (${\pm}8.4$) and the limit of detection was approximately 0.1 pg/g at S/N ratio >3. Finally, the detected concentrations of dioxin-like PCBs for fish and shellfish were in the range of 0.030-1.836 pg TEQ/g.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.95-100
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• 2004

The main objectives of the study were to investigate cultural characteristics of Phellinus linteus. The optimum culture media for mycelial growth of P. linteus were MYA (malt yeast agar) and SMS (soybean powder malt Sucrose). Similarly, optimum temperature and pH were $30^{\circ}C$ and 6.0, respectively. Malt extract (2%, v/v) and yeast extract (0.2%, v/v) were optimum carbon and nitrogen sources. Similarly, 0.1% $KH_2PO_4$ was optimum mineral salt. Highest mycelial growth was observed when C/N ratio was 10 : 1. Optimum inoculum amount for flask culture was $5{\sim}6$ mycelial discs (6 mm diameter) per 100 ml of liquid medium, Highest mycelial dry weight was obtained when cultured in 100 ml liquid medium in 300 ml shaking flask after 20 days of shaking culture, For mass liquid culture (8 l), flask culture was homogenized and used as an inoculum. Optimum culture period and aeration rate for 8l fermentation culture were 12 days and 2.0 vvm, respectively.

• Korean Journal of Medicinal Crop Science
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• v.10 no.3
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• pp.155-161
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• 2002

Using semi-selective (SS-) and selective (Jee-) medium, we identified the pathogens isolated from the symptomatic plants and soils collected from different locations, such as Suwon, Andong, and Youngju, as P. drechsleri, which is Phytophthora root rot causal agent of A. macrocephala. At $25^{\circ}C$, these isolates were grown faster on 10% V8A (V8 juice agar) medium than on PDA (potato dextrose agar) with hyphal swelling, but no growing was observed at below $5^{\circ}C$ and over $40^{\circ}C$. In order to identify the pathogenicity of each isolate, seedlings of A. macrocephala were inoculated with mycelium -zoospore suspended inoculum, which was prepared by culturing on 10% V8A medium and homogenizing in distilled water. By this method, wide ranges of pathogenicity were observed as follows; $5.0%{\sim}26.4%$ of disease severities concerning the lesion areas of the top plants and $23.5%{\sim}72.2%$ of disease incidences. Therefore, this was considered as a efficient method to identify the pathogenicity of P. drechsleri in large scale screening. P-A200073, isolated from soils in Andong, and P-9755, from the root of symptomatic plant of A. macrocephala in Suwon, showed the highest degree of pathogenicity to the seedlings. By these isolates, lesion areas and disease incidences of the inoculated seedlings were occurred $26.4%{\sim}63.2%$ and $25.1%{\sim}72.2%$, respectively. However, no symptoms were observed in uninoculated control. Same pathogens were reisolated from roots and lower stems of the inoculated plants, but not from leaves.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.80-84
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• 1988

The change of cell counts of Vibrio vulnificus in meat homogenates of fish and shellfish by the storage time and temperature was examined to get basic information for precautionary steps against septicemia from slices of raw fish (sashimi). Therefore, we inoculated raw and cooked meat homogenates of fish and shellfish with Vibrio vulificus M-8 (isolated from shellfish ) and stored them at $-20^{\circ}C,\;4^{\circ}C\;and\;30^{\circ}C$ for 72 hours. Vibrio vulnificus M-8 was not detected in 32 hours when it was frozen and stored at $-20^{\circ}C$ after inoculating them into phosphate buffer solution at concentration of $10^5\;cell/ml$, while the existance of Vibrio vulnificus was identified after 72 hours of storage at the same temperature in case of inoculation into the meat homogenate of yellow tail. The cell count of Vibrio vulnificus was decreased as about $20\%$ of initial count after 2 hours storage at $4^{\circ}C$ in phosphate buffer solution with fish and shellfish homgenates. From the experimental results it was recognized that Vibrio vulnificus was labile to the cold stress. In comparison to the growth of growth of Vibrio M-8 at $30^{\circ}C$ in the raw and cooked meat of the yellow tail(Seriola guingueradita), snapper(Chrysophrys major), ark shell(Anadra brouhgtonii), and oyster(Crassostrea gigas), the raw meat homogenates were more excellent than the cooked ones though all fish and shellfish meat homogenates were proves to be good for the growth of the microbe.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.109-117
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• 1989

The changes in adenosine triphosphate (ATP), creatine phosphate (CP) and lactic acid (LA) contents of guinea pig hearts were studied during the cardioplegia and recovery phase. 1) ATP and CP contents in cardiac ventricular tissue were decreased during the cardioplegia, regardless of $Ca^{2+}$ concentration in the cardioplegic solutions, and CP contents were recovered with the reperfusion of normal Tyrode solution faster than those of ATP. And there were no significant differences in the recovery of CP contents with different concentration of $Ca^{2+}$ in the cardioplegic solutions tested, while the recovery of ATP contents was faster with 15 mM $K^{+}$, 0.1 mM $Ca^{2+}$ cardioplegic solutions. 2) LA contents were increased during the cardioplegia and decreased with the reperfusion of normal Tyrode solution. 3) The more recovery time (up to 3 hrs), the more CP contents were recovered with the reperfusion of normal Tyrode solution faster than those of ATP. And LA contents were decreased as the duration of recovery time. These results suggest that $Ca^{2+}$ and $K^{+}$ concentration in the cardioplegic solution is one of the major factors influencing the recovery of cardiac tissue from the cardioplegia.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.2
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• pp.113-118
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• 2014

So many nationwide drinking water treatment plants are under much difficulties by new reinforced discharged effluent standards. Generally, the sludge at thickener should be retended for a long time during usual days. Sometime, the soluble manganese and chloroform may be formed under the anaerobic condition in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. It was necessary to improve the operation conditions and process itself in order to meet water quality standard recently reinforced. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. Sludge aeration prevent particle oxidated Manganese eluting soluble de-oxidated Manganese, excrete formated Chloroform from effluent to air, and improve sludge settling through homogenized sludge particle. We aerated sludge at the conventional water treatment plant, measured Manganese and Chloroform of clarified water at upper sludge, and solid-fluid interface height of sludge in mass cylinder. As a result, contaminant's concentrations of the final effluent was much decreased : 41% of manganese, approximately 62% of chloroform and 35% of sludge volume, compared with non-aeration sludge.

• Applied Microscopy
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• v.33 no.2
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• pp.117-130
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• 2003

This research investigates the fine structural as well as the morphological changes of the mouse ovarian tissue after irradiation of various dose rates of 6 MeV LINAC radiation. The normal structure of the ovarian tissue is consisted of various stages of follicles including primordial and growing follicles, and ovarian stromal connectives. When we observed the ovarian tissues irradiated with a dose rate of 200 cGy/min using light and electron microscopes, granular cells in growing follicles are in irregular shape unlike normal follicles. Small segments of cells scattered in follicular antrum among granular cells. We could observe neutrophils and macrophages around the segments, which means the cells already got in the process of decease owing to the effects radiation. With coincident to the increase of the dose rate of x-ray irradiation as 400 or 600 cGy/min, the mature follicles appeared as an irregular form and the granular cells surrounding oocyte also deformed comparing to their normal counterparts. The granulosa cells within mature follicle are already occurred necrotic change and apoptosis. The nuclei in some cells got so fragmented that the segments formed the shape of a horseshoe or scattered in small and condensed pieces. All the cells at a granular layer irradiated with a dose rate of 600 cGy/min show typical characteristics of apoptosis. The neutrophils involved in inflammatory reaction appear evidently in follicular antrum of growing follicles, and macrophage scattered with residual and apoptotic bodies.

• Journal of Life Science
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• v.27 no.7
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• pp.790-795
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• 2017

The purpose of this study was to evaluate the anti-oxidative effects of fermented Hibiscus syriacus extract on obese mice. The antioxidant experiments were conducted both in vivo and in vitro. The in vitro experiment was measured through the use of nitric oxide (NO) free radical scavenging activity. The results showed that the scavenging activity of the NO free radical in fermented Hibiscus syriacus extract had higher activity than unfermented Hibiscus syriacus extract. The in vivo experiments were divided into a normal dietary group, a high fat dietary group (CON), a high fat dietary + fermented Hibiscus syriacus extract group (FH), and a high fat dietary + unfermented Hibiscus syriacus extract group. These four groups received intraperitoneal administrations for four weeks. Next, the levels of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) in a liver homogenate were measured. The results showed that the levels of SOD and CAT in FH were higher than the CON and MDA levels, which were significantly decreased in FH. Consequently, fermented Hibiscus syriacus extract had an inhibitive effect on oxidative stress and a heightening effect on antioxidant enzyme activity in obese mice, suggesting that fermented Hibiscus syriacus extract could be utilized as a useful, natural antioxidant.

• Journal of Life Science
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• v.19 no.8
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• pp.1055-1061
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• 2009

${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors are widespread throughout the central nervous system and appear to serve as synaptic receptors for fast excitatory synaptic transmission mediated by glutamate. Their modulation is believed to affect learning and memory. To identify the interaction proteins for the AMPA receptor subunit glutamate receptor-interacting protein 1 (GRIPl), GRIP1 interactions with armadillo family protein p0071/plakophilin-4 were investigated. GRIP1 protein bound to the tail region of p0071/plakophilin-4 but not to other armadillo family protein members in a yeast two-hybrid assay. The "S-X-V" motif at the carboxyl (C)-terminal end of p0071/plakophilin-4 is essential for interaction with GRIP1. p0071/plakophilin-4 interacted with the Postsynaptic density-95/Discs large/Zona occludens-1 (PDZ) domains of GRIPI in the yeast two-hybrid assay, as is indicated also by Glutathione S-transferase (GST) pull-down, and co-immunoprecipitated with GRIP1 antibody in brain fraction. The findings of this study provide evidence that p0071/plakophilin-4 is an interactor of GRIP1.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.196-196
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• 2016

치과나 기공소로부터 높은 원가로 인한 재료선택에 어려움을 겪고 있어 귀금속 금합금의 물성을 가질 수 있도록 하면서 가격급등으로 인한 문제 해결하기 위한 비귀금속 합금으로 대체가 필요하기에 이에 따른 연구가 이루어져 국산 제품의 상품화를 위해 파라듐을 이용하여 적합한 새로운 합금을 개발하는 것이 필요하다. 치과용 골드합금은 미국치과의사 협회의 구정에 의하면 1형부터 4형까지 분류하고 있으며 3형에 해당하는 강도와 기계적인 특성을 갖도록 파라듐으로 대체하는 연구가 진행중이거나 시판되고 있다. 따라서 본 연구에서는 2형, 3형 및 4형을 대체가능하도록 팔라듐을 기반으로 한 새로운 합금을 설계하고 합금의 성분원 소인 Au(1~5), Pd(20~25), Ag(70~75), In(1.5) 및 Zn(2)등으로 조성을 변화시켜 측량 후 합금을 제조하기 위하여 아르곤 분위기하의 진공아크용해로를 이용하여 용해하였다. 정량된 금속을 진공아크 용해로에 장입하고 용해는 균질한 합금이 되도록 최소한 6회 이상 용융을 실시하며 합금성분의 손실이 발행하지 않도록 보정을 하였다. 합금의 미세조직 관찰을 위하여 샘플을 고속 다이아몬드 정밀 절단기(Acculom-5, STRUERS, Denmark)를 이용하여 절단한 후 2000 grit의 Sic 연마지에서 단계적으로 $0.3{\mu}m$ 알루미나 분말까지 연마한 후 초음파 세척을 하였다. 준비한 시편은 KCN과 $(NH_4)_2S_2O_8$을 1:1로 혼합한 부식액으로 에칭한 후 OM과 SEM을 이용하여 조직을 관찰하였으며 각 샘플의 성분변화는 EDS 분석을 통해 확인하고 결정구조는 XRD를 사용하여 분석하였다. 경도시험은 비커스경도시험기를 이용하여 5kg의 하중을 30초간 작동시켜 압흔을 연결된 micron으로 평균값을 측정하였다. 각 시편의 부식거동은 POTENTIOSTAT(Model PARSTAT 2273, EG&G, USA)을 이용하여 구강 내환경화 유사한 $36.5{\pm}1^{\circ}C$의 0.9% NaCl에서 실시하였다. 인가전위는 -1500mV에서 1000mV까지 1.67 mV/min의 주사속도로 인가하여 시험을 수행하였으며 분극곡선으로부터 부식전위와 부식전류밀도 및 부동태영역의 전류밀도로 금속의 용출거동을 조사하였으며 부식이 끝난 시편은 FE-SEM과 EDS를 사용하여 조사하였다. 기계적인 특성은 Pd-Ag에 3wt%의 Au를 첨가한 합금이 Pd-Ag에 1.5wt%합금을 첨가한 경우에 비하여 기계적인 특성이 증가하고 내식성이 크게 증가하였다. 이들 합금에 Cu를 11wt%를 첨가한 경우는 비커스경도가 200이상으로 높게 나타났지만 내식성이 크게 감소하였다.