• 대한화학회지
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• 제62권5호
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• pp.412-416
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• 2018

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.980-981
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• 2008

Mechanical spring and hydraulic pressure operated mechanisms are applied in most of today's High Voltage Gas Insulated Switchgear(GIS)s. This paper proposes a new type of operation mechanism for GIS circuit breakers rated at 245kV and 40kA. The Motor-Direct-Drive-Mechanism (MDDM) has many advantages compared to conventional operating mechanisms. It has a very simple structure with only one moving part, low mechanical stress and audible noise. It also allows monitoring, operation speed control and self-diagnosis functions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.114-116
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• 2007

Mechanical spring and hydraulic pressure operated mechanisms are applied in most of today's High Voltage Gas Insulated Switchgear(GIS)s. This paper proposes a new type of operation mechanism for GIS circuit breakers rated at 245kV and 40kA. The Motor-Direct-Drive-Mechanism (MDDM) has many advantages compared to conventional operating mechanisms. It has a very simple structure with only one moving part, low mechanical stress and audible noise. It also allows monitoring, operation speed control and self-diagnosis functions.

• 동의생리병리학회지
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• 제17권4호
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• pp.1013-1018
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• 2003

Cheonghunhwadam-tang(CHT) have been used in oriental medicine for many centuries as a therapeutic agent of vertigo by wind, fire and phlegm. CTG was CHT adding Aurantii FructusㆍGastrodae Rhizoma. CTG was significantly increased regional cerebral blood f1ow(rCBF) in a dose-dependent, and CTG was decreased mean arterial blood pressure(MABP) compared with normal MABP(100%) in a low dosage, but was increased MABP in a dose-dependent, was aliked with normal MABP in a high-dosage. Therefore, purpose of this Study was to investigate experimental mechanism of CHTAG on the cerebral hemodynamics(rCBF, MABP) in rats. The changes of rCBF and MABP were determinated by Laser-Doppler Flowmetry(LDF). The results were as follows ; Pretreatment with indomethacin(3㎎/㎏, i.v.) was significantly inhibited CTG induced increase of rCBF and pretreated with propranolol(3㎎/㎏, i.v.) was inhibited CTG induced increase of rCBF, but pretreatment with methylene blue(10㎍/㎏, i.v) was increased CTG induced increase of rCBF. Pretreatment with indomethacin was decreased CTG induced increase of MABP, but pretreatment with propranolol and methylene blue were increased CTG induced increase of MABP. This results suggest that the mechanism of CTG is mediated by cyclooxygenase.

• 대한화학회지
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• 제60권6호
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• pp.462-466
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• 2016

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권2호
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• pp.239-244
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• 2017

We experimentally investigate the physical mechanism for asymmetrical degradation in amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) under simultaneous gate and drain bias stresses. The transfer curves exhibit an asymmetrical negative shift after the application of gate-to-source ($V_{GS}$) and drain-to-source ($V_{DS}$) bias stresses of ($V_{GS}=24V$, $V_{DS}=15.9V$) and ($V_{GS}=22V$, $V_{DS}=20V$), but the asymmetrical degradation is more significant after the bias stress ($V_{GS}$, $V_{DS}$) of (22 V, 20 V) nevertheless the vertical electric field at the source is higher under the bias stress ($V_{GS}$, $V_{DS}$) of (24 V, 15.9 V) than (22 V, 20 V). By using the modified external load resistance method, we extract the source contact resistance ($R_S$) and the voltage drop at $R_S$ ($V_{S,\;drop}$) in the fabricated a-IGZO TFT under both bias stresses. A significantly higher RS and $V_{S,\;drop}$ are extracted under the bias stress ($V_{GS}$, $V_{DS}$) of (22 V, 20V) than (24 V, 15.9 V), which implies that the high horizontal electric field across the source contact due to the large voltage drop at the reverse biased Schottky junction is the dominant physical mechanism causing the asymmetrical degradation of a-IGZO TFTs under simultaneous gate and drain bias stresses.

• Applied Biological Chemistry
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• 제37권2호
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• pp.124-129
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• 1994

25%(v/v) dioxane 수용액의 넓은 pH범위에서 살충성 $O,O-Diethyl-{\alpha}-cyanobenzylideneamino-oxyphosphorothioate(Volaton^{\circledR})$의 가수분해 반응은 용매효과 (pH 6.0; m=0.21, n=1.55, pH 12.0; m=0.42, n=3.14 및 $|m|{\ll}|l|$), 반응 속도식, 일반염기 촉매효과, 가수분해 반응생성물 분석 및 분자 궤도(MO) 함수 계산 등의 결과로부터 trigonal bipyramidal$(sp^3d^2)$중간체를 경유하여 pH 7.0 이하에서는 $A_{AC}2$형 반응, 그리고 pH 9.0 이상에서는 $B_{AC}2$형 반응이 일어난다. Volaton의 가수분해 반응성은 입체 장애보다는 양하전 크기$(p{\gg}{\alpha}C_2)$에 의존적이며 $pH\;7.0{\sim}9.0$ 사이에서는 이들 두 반응이 경쟁적으로 일어나는 반응 메카니즘을 제안하였다.

• 대한한방내과학회지
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• 제23권1호
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• pp.91-98
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• 2002

Objective : Bangpungtongseongsan(BTS) has been used in oriental medicine for many centuries as a prescription for a heat syndrome of apoplexy. The effects of BTS on the vascular system are not well known. This study is designed to identify the effects of BTS on the regional cerebral blood flow(rCBF), arterial blood pressure and action mechanism in mice. Methods : We measured the change of rCBF and BP by BTS. Secondly, we investigated changes of rCBF and BP for 30 minutes interval after venous inject 0.01, 0.1, 1.0, 10.0mg/kg each density BTS infusion into mice, which were premanaged with methylene blue(10mg/kg, i.v), indomethacin(3mg/kg, i.v.), propranolo(3mg/kg, i.v.) for 30minutes. Results : rCBF increased significantly by BTS in a dose-dependent and BP was not affected by BTS in mice. Pretreatment with methylene blue significantly inhibited rCBF increased by BTS and aceelrated BP not affected by BTS. Pretreatment with indomethacin significantly inhibited rCBF increased by BTS and inhibited BP not affected by BTS. Conclusion : These results show that BTS causes the increasement of rCBF and non-change of BP. The action mechanism is related to prostaglandid activated by cyclooxygenase.

• Molecules and Cells
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• 제43권11호
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• pp.953-963
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• 2020

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an infectious disease with multiple severe symptoms, such as fever over 37.5℃, cough, dyspnea, and pneumonia. In our research, microRNAs (miRNAs) binding to the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory-related coronavirus (MERS-CoV), and SARS-CoV-2 were identified by bioinformatic tools. Five miRNAs (hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-16-5p, and hsa-miR-196a-1-3p) were found to commonly bind to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also identified miRNAs that bind to receptor proteins, such as ACE2, ADAM17, and TMPRSS2, which are important for understanding the infection mechanism of SARS-CoV-2. The expression patterns of those miRNAs were examined in hamster lung samples infected by SARS-CoV-2. Five miRNAs (hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-221-3p, hsa-miR-140-3p, and hsa-miR-422a) showed differential expression patterns in lung tissues before and after infection. Especially, hsa-miR-15b-5p and hsa-miR-195-5p showed a large difference in expression, indicating that they may potentially be diagnostic biomarkers for SARS-CoV-2 infection.

• 약학회지
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• 제58권1호
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• pp.7-11
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• 2014

To study the resistance mechanism of E. faecalis to LCB01-0371, several resistant mutants to LCB01-0371 or linezolid were isolated by step-wise selection. The frequency of spontaneous mutations resistant to LCB01-0371 was lower than that of linezolid in E. faecalis. The genetic variations in resistant mutants were analyzed by DNA sequencing of domain V of 23S rRNA in each mutant. The first-step mutant to LCB01-0371 had a G2576T point mutation in V domain of 23S rRNA. However, no resistant mutant to LCB01-0371 was isolated in second-step mutant selection.