• Title/Summary/Keyword: K-6

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An Association Study of a D6S274(6p23) Polymorphism on Chromosome 6 with Korean Schizophrenic Patients (한국인 정신분열증 환자와 6번 염색체 D6S274(6p23) 다형성의 연합)

  • Kim, Gil-Sook;Lee, Young-Ho;Yang, Byung-Hwan;Han, Jin-Hee;Kim, Leen;Oh, Dong-Yul;Kwak, Sang-Kon;Choi, Jae-Young;Yrm, Sang-Hwa
    • Korean Journal of Biological Psychiatry
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    • v.3 no.2
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    • pp.162-169
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    • 1996
  • An association study with korean schizophrenic patients(N=75) and normal controls(N=87) was performed to find the relationship between D6S274 polymorphism and schizophrenia using polymerase chain reaction. Nine different alleles of a dinucleotide polymorphism on D6S273 locus were observed in both group. When we compared the frequencies of alleles between schizophrenics and normal controls, there was no significant difference between two groups. To increase homogeneity of schizophrenic group, we divided schizophrenic group by clinical phenotypes such as DSM-IV diagnostic subtype, family history, negative and positive symptoms(PANSS), soft neurologic signs(NES-K). Then we compared the frequencies of alleles among subgroups of clinical phenotypes. there was only significant difference between two subgroups on soft neurologic signs(p<0.05). Although our findings fail to provide on evidence of association between schizophrenia and D6S274 locus, follow-up investigation of this locus may be needed in homogeneous subtypes of schizophrenia and schizophrenic pedigrees.

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Measurement and Characterization of Atmospheric SF6 at Korea GAW Center in 2007 (기후변화감시센터의 대기 중 2007년 육불화황 측정 결과 및 특성)

  • Yoo, Hee-Jung;Kim, Jeong-Sik;Lee, Jeong-Soon;Moon, Dong-Min;Lee, Jin-Bok;Kim, Jong-Ho;Kim, Sang-Hoon;Lee, Il-Yong
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.1
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    • pp.1-15
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    • 2011
  • Korea Global Atmosphere Watch Center (KGAWC), which is located in Anmyeondo and, belongs to the Korea Meteorological Administration (KMA), measures sulfur hexafluoride ($SF_6$) in every hour since 2007. In this study, $SF_6$ observed in 2007 are discussed. A gas chromatograph-electron capture detector (GC-ECD) with pre-cooled device is applied during the observation, and produced data are qualified by means of periodic calibration with $SF_6$ standard gas made by Korea Research Institute of Standard and Science (KRISS). $SF_6$ has been greatly paid attention since Kyoto protocol because of its high global warming potential(GWP) with 22,200 times of $CO_2$ in the period of 100 years. It is a man-made compound and has been usually used for gas insulation since 1970s and for etching process in the information technology-based industry since 1990. Average mixing ratio of $SF_6$ in 2007 was 6.65 pmol/mol at Anmyeondo. According to the GAW report published in 2008, average mixing ratio of $SF_6$ in the atmosphere is continuously growing. At present, the average mixing ratio of $SF_6$ in the atmosphere is known to be approximately 6.25 pmol/mol at global observatory. $SF_6$ value in Anmyeondo shows 0.40 pmol/mol greater than that of the Mauna Loa observatory in 2007.

5-Hydroxytryptamine 6 Receptor (5-HT6R)-Mediated Morphological Changes via RhoA-Dependent Pathways

  • Rahman, Md. Ataur;Kim, Hanna;Lee, Kang Ho;Yun, Hyung-Mun;Hong, Jung-Hwa;Kim, Youngjae;Choo, Hyunah;Park, Mikyoung;Rhim, Hyewhon
    • Molecules and Cells
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    • v.40 no.7
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    • pp.495-502
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    • 2017
  • The $5-HT_6R$ has been considered as an attractive therapeutic target in the brain due to its exclusive expression in the brain. However, the mechanistic linkage between $5-HT_6Rs$ and brain functions remains poorly understood. Here, we examined the effects of $5-HT_6R$-mediated cell morphological changes using immunocytochemistry, Western blot, and live-cell imaging assays. Our results showed that the activation of $5-HT_6Rs$ caused morphological changes and increased cell surface area in HEK293 cells expressing $5-HT_6Rs$. Treatment with 5-HT specifically increased RhoA-GTP activity without affecting other Rho family proteins, such as Rac1 and Cdc42. Furthermore, live-cell imaging in hippocampal neurons revealed that activation of $5-HT_6Rs$ using a selective agonist, ST1936, increased the density and size of dendritic protrusions along with the activation of RhoA-GTP activity and that both effects were blocked by pretreatment with a selective $5-HT_6R$ antagonist, SB258585. Taken together, our results show that $5-HT_6R$ plays an important role in the regulation of cell morphology via a RhoA-dependent pathway in mammalian cell lines and primary neurons.

Heteroexpression and Functional Characterization of Glucose 6-Phosphate Dehydrogenase from Industrial Aspergillus oryzae

  • Guo, Hongwei;Han, Jinyao;Wu, Jingjing;Chen, Hongwen
    • Journal of Microbiology and Biotechnology
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    • v.29 no.4
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    • pp.577-586
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    • 2019
  • The engineered Aspergillus oryzae has a high NADPH demand for xylose utilization and overproduction of target metabolites. Glucose-6-phosphate dehydrogenase (G6PDH, E.C. 1.1.1.49) is one of two key enzymes in the oxidative part of the pentose phosphate pathway, and is also the main enzyme involved in NADPH regeneration. The open reading frame and cDNA of the putative A. oryzae G6PDH (AoG6PDH) were obtained, followed by heterogeneous expression in Escherichia coli and purification as a his6-tagged protein. The purified protein was characterized to be in possession of G6PDH activity with a molecular mass of 118.0 kDa. The enzyme displayed maximal activity at pH 7.5 and the optimal temperature was $50^{\circ}C$. This enzyme also had a half-life of 33.3 min at $40^{\circ}C$. Kinetics assay showed that AoG6PDH was strictly dependent on $NADP^+$ ($K_m=6.3{\mu}M$, $k_{cat}=1000.0s^{-1}$, $k_{cat}/K_m=158.7s^{-1}{\cdot}{\mu}M^{-1}$) as cofactor. The $K_m$ and $k_{cat}/K_m$ values of glucose-6-phosphate were $109.7s^{-1}{\cdot}{\mu}M^{-1}$ and $9.1s^{-1}{\cdot}{\mu}M^{-1}$ respectively. Initial velocity and product inhibition analyses indicated the catalytic reaction followed a two-substrate, steady-state, ordered BiBi mechanism, where $NADP^+$ was the first substrate bound to the enzyme and NADPH was the second product released from the catalytic complex. The established kinetic model could be applied in further regulation of the pentose phosphate pathway and NADPH regeneration of A. oryzae to improve its xylose utilization and yields of valued metabolites.

Metal Ion Catalysis and Inhibition in Nucleophilic Substitution Reactions of 4-Nitrophenyl Nicotinate and Isonicotinate with Alkali Metal Ethoxides in Anhydrous Ethanol

  • Choi, Seo-Young;Hong, Yeon-Ju;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1951-1956
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    • 2011
  • A kinetic study is reported on nucleophilic substitution reactions of 4-nitrophenyl nicotinate 5 and isonicotinate 6 with alkali metal ethoxide EtOM (M = K, Na, and Li) in anhydrous ethanol at $25.0{\pm}0.1^{\circ}C$. Plots of pseudo-first-order rate constant $k_{obsd}$ vs. EtOM concentration exhibit upward curvature for the reactions of 5 and 6 with EtOK and EtONa but are almost linear for those with EtOLi. Dissection of $k_{obsd}$ into $k_{EtO^-}$ and $k_{EtOM}$ (i.e., the second-order rate constant for the reaction with dissociated $EtO^-$ and ion-paired EtOM, respectively) has shown that $k_{EtOK}$ ${\geq}$ $k_{EtONa}$ > $k_{EtO^-}$ but $k_{EtOLi}$ < $k_{EtO^-}$. It has been concluded that $K^+$ and $Na^+$ ions catalyze the reactions by increasing the electrophilicity of the carbonyl carbon atom through formation of a 4-membered cyclic transition state $TS_3$ or $TS_4$. However, $M^+$ ion catalysis has been found to be much less significant for the reactions of 5 and 6 than for the corresponding reactions of 4-nitrophenyl picolinate 4, which was reported to proceed through a 5-membered cyclic transition state $TS_2$. Although 5 and 6 are significantly more reactive than 4-nitrophenyl benzoate 3, the reactions of 5 and 6 result in smaller $k_{EtOK}/k_{EtO^-}$ ratios than those of 3. The electron-withdrawing ability of the nitrogen atom in the acyl moiety of 5 and 6 has been suggested to be responsible for the increase in reactivity and the decrease in the $k_{EtOK}/k_{EtO^-}$ ratio.

A study on the Relationship between Load Current and Temperature of 6.6 kV Cable Systems in Operation (운전중 6.6kV 케이블 시스템의 부하전류와 온도의 상관관계 연구)

  • Lee, Kwan-Woo;Hwang, Yung-Ha;Lee, Sang-Hun;Um, Keehong
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1157-1158
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    • 2015
  • This work is to study the effect of load current on 6.6 kV power cables in operation. In order to figure out the relationship between load current and temperature of the power cables, we have developed measuring equipment for insulation resistance, temperature, and current tested on 9 cables at power station, Western Power Co. Ltd. The cables used in our test were in operation for the last 18 years. Our research over a year showed that the remaining lifetime of 8 cables was more than 20 years. The remaining lifetime of one cable was about 16 to 18 years.

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The Accident Analysis of 6.6kV CV Cable (6.6kV 케이블 사고분석)

  • Shong, Kil-Mok;Kim, Young-Seok;Kim, Hyang-Kon;Choi, Chung-Seog
    • Proceedings of the KIEE Conference
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    • 2005.11c
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    • pp.60-63
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    • 2005
  • In this paper, the accidents of 6.6kV CV cable using many analysis methods such as a pattern anlysis were analyzed; the inner structure analysis; cross section analysis; SEM; EDX, etc. With the analysis and the accident reconstruction, It was possible to analyze the accident causes. For more correct assessment, another accident reconstruction and simulation with a software were required.

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6.6kW High Power Density Bridgeless Single-stage On-board Charger (고전력밀도를 갖는 6.6kW급 브리지리스 단일단 차량탑재형 충전기)

  • Kim, Byeongwoo;Park, Junsung;Kim, Minjae;Choi, Sewan
    • Proceedings of the KIPE Conference
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    • 2015.07a
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    • pp.297-298
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    • 2015
  • 본 논문에서는 고전력밀도를 갖는 6.6kW급 브리지리스 단일단 차량탑재형 충전기를 제안한다. 제안하는 충전기는 넓은 동작영역에서 스위치의 ZVS 턴온 및 다이오드의 ZCS 턴오프를 성취한다. 또한 변압기 1차측에 제안한 결선방식을 적용하여 변압기에 저주파 성분을 제거함으로써 변압기 코아부피를 최적화할 수 있다. 본 논문에서는 제안하는 충전기의 동작원리를 제시하고 모의실험을 통해 본 논문의 타당성을 검증하였다.

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Design of 6.6kW On-Board Battery Charger for Electric Vehicle using Phase-Shift Full-Bridge Converter (PSFB 컨버터를 이용한 전기자동차용 6.6kW 탑재형 충전기 설계)

  • Ahn, Jung-Hoon;Kim, Yun-Sung;Koo, Keun-Wan;Lee, Byoung-Kuk
    • Proceedings of the KIPE Conference
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    • 2012.07a
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    • pp.166-167
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    • 2012
  • 본 논문은 전기자동차 (Electric Vehicles, EVs)용 리튬 이온 (Li-Ion) 배터리의 충전 및 충전 속도 향상을 위하여 6.6kW급 고전력 탑재형 충전기 (On-Board Charger, OBC)를 설계한다. 높은 부하 가변범위와 차량 실장 특성을 고려하여 가용 가능한 토폴로지들 중 최적의 토폴로지로 위상천이 풀-브릿지 컨버터 (Phase-Shift Full-Bridge, PSFB)를 제안하고 타당성을 밝힌다. 또한 토폴로지를 구동하는 스위칭 주파수와 주요 수동소자의 변화에 따른 부피와 효율 등의 Trade-Off 관계를 이론적으로 전개하여 최적화한다.

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Development of simulation on parallel operation of the On-Board Charger (차량용 OBC 병렬운전 시뮬레이션 개발)

  • Zhu, Helin;Mok, HyungSoo;Choi, Sungho;Park, SungUk;Sung, KiHak
    • Proceedings of the KIPE Conference
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    • 2018.11a
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    • pp.225-226
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    • 2018
  • 전기자동차 배터리팩을 충전하기 위한 장치인 차량용 OBC(On-Board Charger)는 AC/DC 컨버터 기능을 담당하는 PFC(Power Factor Correction)와 DC/DC 전력변환 및 전기적 절연을 담당하는 Phase-Shifted Full Bridge Converter를 포함 한다. 현재 시중에 3.3kW급 OBC를 기준으로 규격화되어 생산되고 있지만 전기자동차의 배터리 용량이 날로 증가하고 전기자동차 보급, 사용률이 증가함에 따라 완속충전에 대한 요구가 높아지고 있다. 여기에 전력 인프라 시설 개선과 더불어 6.6kW급 완속충전이 보편화될 수 있게 된다. 차량용 OBC 공급업체에 있어서는 기존의 3.3kW급과 6.6kW급 OBC의 개발 중 어느 쪽에 중심을 둘지 고민에 대한 대안으로 기존의 3.3kW급을 모듈화하여 병렬운전하는 방법으로 6.6kW급 OBC 시장수요에 대응 할 수 있다. 본 논문에서는 3.3kW급 OBC 및 2병렬운전에 관한 시뮬레이션을 개발하고 분석하였다.

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