• 한국전기전자재료학회논문지
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• 제16권7호
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• pp.634-640
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• 2003

This paper is to be researched into ozone generation character of Bi-Ti-Si type high dielectric yield ceramic catalyst discharge tube. And conditions of basic experiment are the outside diameter of discharge tube : 52 mm, the length of discharge tube : 350 mm, the frequence : 900 Hz, the temperature of cooling water : 25 $^{\circ}C$, quantity of flow : 5, 10, 20 l/min, pressure : 1.2, 1.4, 1.6 atm, and distance of discharge gap : 0.4, 0.6, 0.8 mm. Ozone generation characteristics were measured to consumption power. At quantity of flow : 20 l/min, discharge gap : 0.6 mm, pressure : 1.6, and consumption power : 150 W, Maximum ozone generation efficiency of 175 g/kWh was obtained. Maximum ozone generation efficiency was measured below the flow quantity of 20 l/min at below pressure of 1.6 atm. However, Maximum ozone generation efficiency was measured over the flow quantity of 20 l/min at over pressure of 1.6 atm.

• BMB Reports
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• 제32권1호
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• pp.72-75
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• 1999

In an effort to understand the function of the eryBVII gene in the erythromycin biosynthetic gene cluster, we overexpressed the eryBVII gene in E. coli and TDP-6-deoxy-L-threo-D-glycero-4-hexulose was used as a substrate of the overexpressed EryBVII enzyme. The enzymatic reaction product was chemically modified by reduction and peracetylation. Structural analysis of the derivatized enzymatic products by GC-Mass Spectrophotometry indicated that TDP-6-deoxy-L-threo-D-glycero-4-hexulose could be converted into its epimer by EryBVII enzyme. Based on this result, TDP-6-deoxy-L-threo-D-glycero-4-hexulose was indeed the substrate of EryBVII enzyme and the function of the eryBVII gene was confirmed.

• 한국임상수의학회지
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• 제15권1호
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• pp.79-82
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• 1998

This study was performed to determine the changes of serum enzyme activities in rats with hepatic injury induced by the administration of AAPH. Minor behavioral change, brittleness of skin hair and decreased water and fled intake were observed in rats administered intraperitoneally with AAPH. Serum AST and ALT activities pre-treatment were $65{\pm} 13.8 and 32{\pm}$ 12.6 IU/L, respectively and increased sharply from 2 hours of administration and reached $1248{\pm} 77.6 and 946{\pm}$ 45.6 IU/L, respectively at 48 hours of administration. Serum ALP and $\gamma -GTP activities pretreatment were 221 {\pm} 75.6 and 2.2{\pm}$ 0.35 IU/L respectively and increased sharply from 8 hours of administration and reached $767{\pm} 44.9 IU/L and 8.0{\pm} 1.23 IU/L,$ respectively at 48 hours of administration.

• 대한수학회지
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• 제44권6호
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• pp.1383-1396
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• 2007

The aim of this paper is to study L-fuzzy uniformizable spaces. A new kind of topological fuzzy remote neighborhood system is defined and used for investigating the relationship between L-fuzzy co-topology and L-fuzzy (quasi-)uniformity. It is showed that this fuzzy remote neighborhood system is different from that in [23] when $\mathcal{U}$ is an L-fuzzy quasi-uniformity and they will be coincident when $\mathcal{U}$ is an L-fuzzy uniformity. It is also showed that each L-fuzzy co-topological space is L-fuzzy quasi-uniformizable.

• 미생물학회지
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• 제26권1호
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• pp.52-59
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• 1988

A partially purified preparation of L-galactonolactone oxidase which catalyzes the last step of L-ascorbic acid biosynthesis was obtained from Saccharomyces cerevisiae ATCc 26787. The purification procedures included Triton X-100 treatment, protamine sulfate precipitation, ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange chromatography, Sephadex G-150 gel filtration chromatography, and Phenyl-Sepharose CL-4B hydrophobic interaction chromatography. The optimum temperature for the enzyme activity was about $34^{\circ}C$ and the optimum pH was 6.8-7.0. The substrate specificity was confined to L-aldonolactones, L-galactono-1,4-lactone and L-gulono-1,4-lactone. An apparent Km value of 0.294mM with L-galactono-1,4-lactone as a substrate was found. By comparing the substrate specificities of this enzyme with those of isofunctional enzymes of higher plants and animals, it becomes evident that the enzyme of S. cerevisiae ATCC 26787 is rather similar to the L-gulonolactone oxidase of animals than the galactonolactone dehydrogenase of higher plants.

• 생명과학회지
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• 제28권1호
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• pp.17-25
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• 2018

본 연구에서는 아토피 피부염 동물 모델에 대한 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004의 면역조절 효과를 확인하고자 하였다. 가려움증의 횟수와 유출된 evans blue, 그리고 혈청 IgE와 histamine의 농도는 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004를 섭취한 그룹에서 아토피 피부염 유발그룹에 비해 유의적으로 감소하는 결과를 나타내었다. 아토피 피부염이 유발되면 전사 수준에서 Th2 및 Th17 세포의 전사인자 및 cytokine은 과발현되며, ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004를 섭취하였을 때 이를 유의적으로 감소되었다. 또한 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004는 Th1 및 Treg 세포의 전사인자(T-bet, GATA-3, $ROR{\gamma}T$, Foxp3) 및 cytokine (INF-${\gamma}$, IL-4, IL-17, TGF-${\beta}$)의 발현을 증가시킴으로써 면역 균형을 조절하는 것으로 나타났다. Galectin-9과 filaggrin은 아토피피부염 유발 처리군에서 유의적으로 가장 낮았으며, ${\beta}$-1,3/1,6-glucan 처리군에서 유의적으로 가장 높게 나타났다. 이와 반대로 TSLP는 아토피 피부염 유발그룹에서 유의적으로 가장 높았으며 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004를 섭취한 그룹은 대조군과 유사한 수준이었다. 이러한 결과를 통해 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004는 아토피 피부염 동물 모델에서 면역조절 작용 및 아토피 피부염의 개선 효과를 가짐을 알 수 있었다. 따라서 ${\beta}$-1,3/1,6-glucan과 L. plantarum LM1004는 아토피 피부염에 유용한 천연소재로서 사용될 것으로 기대된다.

• 한국환경농학회지
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• 제26권1호
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• pp.42-48
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• 2007

본 조사는 충북지역의 양액재배 농가에서 양액재배를 위한 지하수 수질과 양액 재배 후 버려지는 폐양액의 수질에 대한 기초 자료를 얻고자 수행되었다. 양액재배를 위한 지하수의 수질 조사는 19개 지점의 양액재배농가에서 수집하여 분석하였고, 폐양액은 그중 15개 지점을 선택하여 분석하였다. 양액재배에 이용되는 지하수의 수질 분석결과 pH의 수준은 $6.2\sim7.7$이었고, 평균은 6.8이었다. EC의 분포범위는$0.10\sim0.45$ dS $m^{-1}$ 이었고, 평균은 0.23 dS $m^{-1}$ 이었다. $NO_3-N$ 농도의 분포범위는 $0.12\sim13.77$ mg $L^{-1}$, $SO_4^{2-}$의 분포범위는 $1.84\sim63.01$ mg $L^{-1}$, 그리고 $Cl^-$의 분포범위는 $10.46\sim72.09$ mg $L^{-1}$이었다. 그들의 평균값은 각각 4.00 mg $L^{-1}$, 12.70 mg $L^{-1}$ 및 27.57 mg $L^{-1}$이었다. $Ca^{2+}$, $Mg^{2+}$ 및 $Na^+$의 분포 범위는 각각 $3.24\sim36.99$ mg $L^{-1}$, $1.44\sim14.93$ mg $L^{-1}$ 및 $6.12\sim25.25$ mg $L^{-1}$이었고, 평균 농도 값은 $Ca^{2+}$ 13.06, $Mg^{2+}$ 6.02 및 $Na^+$ 12.08 mg $L^{-1}$이었다. 양액재배 후 버려지는 폐양액에서 pH 수준은 $4.3\sim8.8$ 이었고, 평균은 6.7이었다. EC의 분포범위는 $0.44\sim2.37$ dS $m^{-1}$이었고, 평균은 1.15 dS $m^{-1}$이었다. $NO_3-N$, $PO_4-P$, $K^+$, $Ca^{2+}$, $Mg^{2+}$ 및 $Na^+$ 의 분포범위는 각각 $10\sim212$, $0.56\sim26.1$, $10\sim295$, $16\sim215$, $9\sim54$ 및 $10\sim53$ mg $L^{-1}$이었다. 평균 농도 값은 $NO_3-N$ 100, $PO_4-P$ 12.15, $K^+$ 99, $Ca^{2+}$ 78, $Mg^{2+}$ 26 및 $Na^+$ 26 mg $L^{-1}$이었다. 양액 재배 후 버려지는 폐양액 중의 무기성분 함량은 양액재배에 이용되는 원수에 비해 상당히 높아졌다.

• 한국양식학회지
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• 제13권4호
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• pp.303-308
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• 2000

대하 양식에 있어 저질성상에 따른 환경변화를 아질산, 암모니아 및 황화수소와 같은 유해물질을 중심으로 파악하고, 이에 따른 대하의 생존 및 성장 등에 미치는 저질조성의 영향을 검토하여 생산성을 평가하기 위하여 실험실 조건에서 6주 동안 실험하였다. 실험종료시 DO는 sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율의 혼합조건에서는 5.1~5.9mg/l까지 감소하였으나, mud 조건에서는 4.6mg/l까지 감소하였다. 또한, 아질산, 암모니아농도 및 황화수소는 sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율 조건에서 각각 0.07~0.12mg/l, 0.16~0.29mg/l 및 0.009~0.014mg/l까지 증가하였으나, mud 조건에서는 0.15mg/l, 0.36mg/l 및 0.018mg/l로 높은 증가를 나타냈다. 대하의 생존율은 bare와 mud 조건에서 60% 이하의 낮은 생존율을 나타냈으나, sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율의 혼합조건에서는 70%이상을 나타냈다. 저질 성상에 따른 대하의 성장과 사료효율은 bare 조건에서 각각 7.6%와 29.4%을 나타내어 성장과 사료효율이 가장 높은 sand+mud 조건에 비해 유의한 감소를 나타냈다.

• Journal of Biosystems Engineering
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• 제30권4호
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• pp.202-209
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• 2005

The output of Stirling engine is influenced by the regenerator effectiveness. The regenerator effectiveness is influenced by heat transfer and flow friction loss of the regenerator matrix. In this paper, in order to provide a basic data for the design of regenerator matrix, characteristics of heat transfer and flow friction loss were investigated by a packed method of matrix in the oscillating flow as the same condition of operation in a Stirling engine. As matrices, 6 kinds of steel wires, 4 kinds of combined steel wires, 8 kinds of combined steel wires with screen meshes were used. The results are summarized as follows; Among 6 kinds of steel wires $({\phi}0.7\;mm,\;{\phi}0.9\;mm,\;{\phi}1.2\;mm,\;{\phi}\;1.6\;mm,\;{\phi}2.0\;mm,\;{\phi}2.7\;mm),$ the two steel wires $({\phi}0.7\;mm,\;{\phi}0.9\;mm)$ showed the highest in effectiveness. Among 4 kinds of combined steel wires $({\phi}l.6-{\phi}l.2\;mm,\;{\phi}1.2-{\phi}l.6\;mm,\;{\phi}0.9-{\phi}l.2\;mm,\;{\phi}l.2-{\phi}0.9\;mm),\;the\;{\phi}1.2-{\phi}0.9\;mm$ showed the highest in effectiveness. Among 8 kinds of combined steel wires with screen meshes $(150-{\phi}0.9\;mm,\;150-{\phi}l.2\;mm,\;{\phi}0.9\;mm-150,\;{\phi}1.2\;mm-150,\;150-{\phi}0.9\;mm-150,\;150-{\phi}1.2\;mm-150,\;150-{\phi}l.6\;mm-150,\;150-{\phi}2.0\;mm-150),\;the\;{\phi}l.2\;mm-150$ showed the highest in effectiveness.

• Plant Biotechnology Reports
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• 제2권4호
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• pp.245-252
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• 2008

The genetic status of somatic embryo-derived plantlets of Cymbopogon flexuosus was examined by randomly amplified polymorphic DNA (RAPD) analysis. Auxins such as 2, 4-dichlorophenoxyacetic acid (2, 4-D) (1-4 mg/l) were used in Murashige and Skoog (MS) medium for induction of calli from rhizomatous explants of Cymbopogon flexuosus. Optimum calli were induced on MS medium supplemented with 2, 4-dichlorophenoxyacetic acid (2, 4-D) (3.5 mg/l) alone or in combination with $N^6-benzyladenine$ (2 mg/l). Somatic embryogenesis was achieved from long term calli when cultured on MS medium containing 2, 4-dichlorophenoxyacetic acid (2, 4-D) (2 mg/l) along with $N^6-benzyladenine$ (BA) (1-2 mg/l). Regeneration was achieved when freshly induced embryogenic calli were sub-cultured on MS medium supplemented with $N^6-benzyladenine$ (3 mg/l) alone. Long-term cultured embryos showed profuse minute rooting on regeneration medium supplemented with N6 -benzyladenine (3 mg/l). Microshoots were rooted in the presence of indole-butyric acid (IBA) (2 mg/l). DNA samples from the mother plant and 18 randomly selected regenerated plants from a single callus were subjected to RAPD analysis with 6 arbitrary decamer primers for the selection of putative somaclones. A total of 64 band positions were scored, out of which 19 RAPD bands were polymorphic. From genetic similarity coefficient based on RAPD band data sharing, it was found that the majority of the clones were almost identical or more than 92% similar to the mother plant, except CL2 and CL9 (66%) which showed highest degree of genetic change with CL2 and CL9 showing presence of two non-parental bands each.