• Korean Journal of Soil Science and Fertilizer
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• v.30 no.1
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• pp.41-45
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• 1997

This study was conducted to investigate methane production, emission and diffusion under organic matter application in paddy soil (Jeonbug Series). The rates of application of rice straw were 5,000kg/ha in combination with 110kg N/ha as chemical fertilizer. In seasonal variations of the $CH_4$ emission rates two maxima were found during the ear formation stage and the heading stage of the rice plant. Entrapped methane increased dining the early growing season, declined thereafter and especially increased during the heading stage. Methane concentration in the soil solution was the higest at 5cm depth, but decreased with upper and lower depth. The gas diffusion rate of $CH_4$ was very slow in the liquid phase. Eh of soil solution varied from -150~-160mV and methane prodution rate was highly correlated with Eh.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.271-277
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• 2015

Anaerobic decomposition of organic material in flooded rice fields produces methane, which escapes to the atmosphere primarily by transport through the rice plants. The annual amount of $CH_4$ emitted from a given area of rice is a function of the number and duration of crops grown, water regimes before and during cultivation period, and organic and inorganic soil amendments. Soil type, temperature, and rice cultivar also affect $CH_4$ emissions. The field experiment was conducted for three years to develop methane emission factor for water regime before the cultivation period from the rice fields. It was treated with three different water regimes prior to rice cultivation, namely: non-flooded pre-season < 180 days, non-flooded pre-season > 180 days, flooded per-season in which the minimum flooding interval is set to 30 days. Methane emission increased with days after transplanting and soil redox potential (Eh) decreased rapidly after flooding during the rice cultivation. The average methane emission fluxes were $5.47kg\;CH_4\;ha^{-1}day^{-1}$in flooded pre-season > 30 days, 5.04 in non-flooded pre-season < 180 days and 4.62 in non-flooded pre-season > 180. Methane emission flux was highly correlated with soil temperature and soil Eh. Rice yields showed no difference among treatments with water regime before the cultivation period.

• Tuberculosis and Respiratory Diseases
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• v.47 no.5
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• pp.691-696
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• 1999

Epithelioid hemangioendothelioma(EH) is a rare pulmonary vascular malignancy. Clinically, EH has been considered as an indolent, generally non-aggressive tumor. We report a case of EH which was confirmed by open lung biopsy. A 34-year-old woman was admitted for further evaluation of multiple small(less than 2cm in size) nodules, incidentally detected on screening chest radiograph. The chest CT showed multiple, relatively well-marginated, variable sized nodules at both whole lung. Transbronchial lung biopsy and transthoracic needle aspiration were nondiagnostic and open lung biopsy was performed from right middle lobe of lung. On light-microscopic examination, the nodules were composed of a poorly cellular hyaline core and a more cellular peripheral zone which extended into air space in a micropolypoid fashion and obliterated blood vessels. The tumor cells at the peripheral zone had intracytoplasmic vacuoles which suggested primitive, vascular differentiation. Immuno-histochemical study revealed the cellular area which gave positive reaction to factor VIII-related antigen. She received no specific therapy after open lung biopsy and chest X-ray films had showed no change for about two years.

• Journal of Life Science
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• v.20 no.5
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• pp.799-804
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• 2010

In humans, CYP2C19, a member of the cytochrome P450 subfamily, metabolizes arachidonic acid to produce epoxyicosanoid acids, which are involved in vascular tone and regulation of blood pressure (BP). Recent findings suggest that CYP2C19 gene polymorphisms might be considered as a novel candidate gene for cardiovascular disease. We thus focused on the Korean population to explore the association of two polymorphisms ($CYP2C19^*2$ and $^*3$) in this gene and essential hypertension (EH). A total of 1,241 participants (537 hypertensive subjects and 704 healthy controls) were recruited from the Yonsei Cardiovascular Genome Center in Korea. The CYP2C19 polymorphisms were genotyped using the $SNaPShot^{TM}$ assay. The allele and genotype frequencies of $CYP2C19^*3$ showed significant difference between hypertensives and normotensives (P=0.019 and P=0.023, respectively). Logistic regression analysis indicated that the $CYP2C19^*3$ A allele carriers were significantly associated with EH (OR, 0.723; 95% CI, 0.538-0.972, P=0.032) under a dominant model. In addition, CYP2C19 G-A haplotype ($2C19^*2\;G-^*3$ A combination) was found to significantly reduce EH risk (OR, 0.714, P=0.015). We believe this provides evidence that $CYP2C19^*3$ polymorphism may contribute to a protective effect in the development of EH.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3447-3452
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• 2014

Detailed chemical investigation of Boscia senegalensis (Per) Lam. ex Poir. led to the isolation of one new flavonol glycoside, rhamnocitrin-3-O-${\beta}$-$\small{D}$-(6"-O-E-feruloyl)-glucopyranoside named bosenegaloside A (1), with seven known compounds, rhamnocitrin-3-O-${\beta}$-$\small{D}$-(6"-O-E-p-coumaroyl)-glucopyranoside (2), rhamnocitrin-3-O-${\beta}$-$\small{D}$-glucopyranoside (3), 3,4,5-trimethoxyphenol-${\beta}$-$\small{D}$-glucopyrinoside (4), lasianthionoside A (5), 3,7-dimethyl-1-octene-3,6,7-triol-6-O-${\beta}$-$\small{D}$-glucopyranoside (6), syringin (7), and austroside B (8). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of these data with previously published results. The inhibitory activity of the isolated compounds on soluble epoxide hydrolase (sEH) was assessed. Compounds 1-3 potently inhibited sEH activity with $IC_{50}$ values of $12.8{\pm}0.5$, $18.4{\pm}0.2$, and $11.3{\pm}0.9{\mu}M$, respectively.

• KSBB Journal
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• v.23 no.5
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• pp.369-374
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• 2008

The effects of reaction temperature and the addition of various detergents on the enantioselective hyrolysis activity of the recombinant Escherichia coli containing the epoxide hydrolase (EH) gene of Rhodotorula glutinis were investigated for the production of enantiopure styrene oxide. The recombinant E. coli harboring the EH gene from R. glutinis exhibited the enantiopreference toward (R)-styrene oxide with the maximum hydrolytic activity of $165.04{\mu}mol/min/mg$ of dry cell weight (dcw). The addition of 0.5% (w/v) Tween 20 at $10^{\circ}C$ increased the initial hydrolysis rate and enantioselectivity by 1.45-fold and 2.0-fold, respectively. Enantiopure (S)-styrene oxide was prepared with 99% ee enantiopurity and 46.0% yield (theoretical yield=50%) from 20 mM racemic styrene oxide.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.112-119
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• 1998

The objective of this study was to investigate the effect of bulking agents including cow manure, saw dust and rice straw in the ripening of leather sludge for vermistabilization. The changes of the waste properties for ripening time for 50 days were observed according to the various mixture ratios of leather sludge and bulking agents. The pH values of the mixture wastes were decreased from 7.5-8.0 to 6.4-7.3 with the ripening time for 50 days, and it was indifferent of the mixture ratio and type of the bulking agent. The initial value of oxidation-reduction potential(Eh) of the mixture waste was a negative(-)value indicating an unfavorable condition for earthworm life, but the values of Eh were increased with the ripening time. The increase rate of Eh value was proportional to the mixture ratio of bulking agents, but the increase rate for saw dust was higher than that of the cow manure and the rice straw. The value of alkalinity was also changed into the favorable range for earthworm after 50 days except for 10% of the mixture ratio of the bulking agents. When the mixture ratios of the bulking agents were increased from 10% to 40%, the growth characteristics of earthworms were increased from 31.7% to 95% for the survival rate, 103% to 225% for the liveweight increase rate and 32% to 91% for hatching rate of the cocoons. It can be concluded that the proper content of the bulking agents in the leather sludge to ensure effective vermistabilization was over 30%, when the mixture was ripened during 50 days. The contents of heavy metals in the ripened sludge were lower than the other regulatory standards for compost.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.134-139
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• 2004

Hybrid cluster protein (HCP) was investigated because of its unique iron-sulfur clusters, which have been found in bacteria and archaea. Here, HCP homologous proteins from the third domain, 'eukarya'(3 amitochondriate protozoans, Giardia lamblia, Entamoeba histolytica, and Trichomonas vaginalis), were identified. All three amitochondriate protozoan HCPs (GlHCP, EhHCP, and TvHCP) belonged to Class I on the basis of two key characters, the cysteine spacing, Cys-(Xaa)₂Cys(Xaa)/sub 7-8/-Cys(Xaa)/sub 5/-Cys, and the absence of N-terminal deletion characteristic to the Class III. In phylogenetic analysis performed with amino acid sequences of 3 eukaryal, 5 bacterial, and 4 archaeal HCPs, the maximum likelihood (ML) tree indicated that TvHCP was clustered with Class I HCPs, whereas the other two HCPs (GlHCP and EhHCP) formed an independent clade with a high bootstrapping value (96%) not belonging to any previously recognized HCP class. In spite of the relatively lower bootstrapping value (61%), the position of the new eukaryal GlHCP-EhHCP clade was close to Class I, including the TvHCP, and Classes II and III were closely related with each other. The finding of eukaryal HCPs would help to understand the evolutionary history of HCP.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.81-81
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• 1995

No Abstract, See Full Text

• JOURNAL OF ELECTRICAL WORLD
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• no.9 s.105
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• pp.92-95
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• 1985

OA기기에서의 접지기술은 어디라든지 그랜드라는 용어를 목적에 따라 구분, 사용하거나 포함하고 있는데 기본적인 목적은 네가지의 경우로 대별된다. 즉 (1)안전면에서 본 감전방지 (2)전자회로에서의 전자방해의 억제는 임피던스를 가진 접지이며 본질적인 문제는 여기에 있다. 한편 OA기기를 설치하는 환경은 대지 접지를 할 수 없는 케이스가 증가되고 있으며 EH 다른 문제가 부상되고 있다. 이같은 시점에서 OA기기에서의 접지기술의 현상과 문제점의 일단을 설명한다.