• Herbal Formula Science
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• v.12 no.1
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• pp.195-208
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• 2004

Objective: This study was conducted to investigate the effects of Aconiti Tuber on the plasma IL-6 and $TNF-{\alpha}$ level in mice stimulated by intracerebroventricular(I.C.V.) Injection of Lipopolysaccharide(LPS). Method: 6 mice were assigned to each of the normal group, the control group, and the experimental group. In the normal group only saline was administered intragastrically, and in the control group LPS was injected intracerebro-ventricularly 1 hr after intragastric administration of saline. In the experimental groups (Aconiti Tuber 0.5g/kg, Aconiti Tuber 1.0g/kg, Aconiti Tuber 3.0g/kg) each sample was administered intragastrically to mice 1 hr prior to the stimulation by LPS I.C.V. Injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of plasma IL-6 and $TNF-{\alpha}$. Result : 1. LPS I.C.V. Injection increased plasma IL-6 level significantly in a dose-dependent manner compared with normal group(P<0.01). The plasma IL-6 concentration reached a significant maximal level about 1 hr after LPS I.C.V. Injection(P<0.001). LPS I.C.V. Injection increased plasma $TNF-{\alpha}$ level significantly in a dose-dependent manner(P<0.05). The plasma $TNF-{\alpha}$ concentration reached a significant maximal level about 1 hr after LPS I.C.V. Injection(P<0.001). 2. Sample A group to which Aconiti Tuber(0.5g/kg) was administered intragastrically 1 hr prior to the stimulation by LPS I.C.V. Injection showed insignificant lower plasma IL-6 level in 1 hr than control group(P<0.0635), and sample B group (Aconiti Tuber 1.0g/kg) showed significant lower plasma IL-6 level in 1 hr than control group(P〈0.05), and sample C group (Aconiti Tuber 3.0g/kg) showed significant lower IL-6 plasma level in 1 hr than control group(P<0.01). 3. sample A group to which Aconiti Tuber(0.5g/kg) was administered intragastrically 1 hr prior to the stimulation by LPS I.C.V. Injection showed insignificant lower plasma $TNF-{\alpha}$ level in 1 hr than control group(P>0.05), and Both sample B(1.0g/kg) and sample C(3.0g/kg) groups showed significant lower $TNF-{\alpha}$ plasma level in 1 hr than control group(P<0.01). These data revealed that Aconiti Tuber might have the anti inflammatory effect by reducing the plasma IL-6 and $TNF-{\alpha}$ level in a dose dependent manner in mice LPS I.C.V. Injection.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.7
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• pp.1-6
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• 2004

For MOSFET devices with nanometer range gate length, accurate extraction of effective gate length is highly important because transistor characteristics become very sensitive to effective channel length. In this paper, we propose a new approach to extract the effective channel length of nanometer range MOSFET by Capacitance Voltage(C-V) method. The effective channel length is extracted using gate to source/drain capacitance( $C_{gsd}$). It is shown that 1/$\beta$ method, Terada method and other C-V method are inadequate to extract the accurate effective channel length. Therefore, the proposed method is highly effective for extraction of effective channel length of 100nm CMOSFETs.s.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.5
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• pp.181-188
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• 2006

Rutile single crystals grown by skull melting method were cut parallel and perpendicular to growth axis, and both sides of the cut wafers (${\phi}5.5mmx1.0mm$) were then polished to be mirror surfaces. The black wafers were changed into pale yellow color by annealing in air at 1200 and $1300^{\circ}C$ for $3{\sim}15\;and\;10{\sim}50$ hours, respectively. After annealing, structural and optical properties were examined by specific gravity (S.G), SEM-electron backscattered pattern (SEM-EBSP), X-ray diffraction (XRD), FT-IR transmittance spectra, laser Raman spectroscopy (LRS), photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). These results are analyzed increase of weight in air, decrease of weight in water and specific gravity, shown secondary phase of needle shape, diffusion of oxygen ion and increase of $Ti^{3+}$. From the above results, we suggest that the skull melting method grown rutile single crystals contain defect centers such as $O_v,\;Ti^{3+},\;O_v-Ti^{3+}$ interstitials and $F^+-H^+$.

• Journal of Power Electronics
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• v.9 no.4
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• pp.604-611
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• 2009

A dP/dV feedback-controlled MPPT (Maximum Power Point Tracking) method for photovoltaic power systems using II-SEPIC (Isolated Inverse-SEPIC; Single Ended Primary Inductance Converter) is presented and a current-mode dP/dV feedback-controlled MPPT method is devised to apply for the PV power converter system. A control strategy for the current-mode dP/dV feedback control system is developed in this paper and the proposed MPPT shows relatively satisfactory dynamics against rapidly changing insolation conditions. In order to verify the validity and effectiveness of the proposed method, simulations and experiments of the PV power system using II-SEPlC converter are performed. These simulation and experiment results show that the proposed method enables the PV power system to extract maximum power from the photovoltaic module against the solar insolation variation.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.987-996
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• 2018

Bacterial programmed cell death is regulated by the toxin-antitoxin (TA) system. YhaV (toxin) and Pr1F (antitoxin) have been recently identified as a type II TA system in Escherichia coli. YhaV homologs have conserved active residues within the C-terminus, and to characterize the function of this region, we purified native YhaV protein (without denaturing) and constructed YhaV proteins of varying lengths. Here, we report a new low-temperature method of purifying native YhaV, which is notable given the existing challenges of purifying this highly toxic protein. The secondary structures and thermostability of the purified native protein were characterized and no significant structural destruction was observed, suggesting that the observed inhibition of cell growth in vivo was not the result of structural protein damage. However, it has been reported that excessive levels of protein expression may result in protein misfolding and changes in cell growth and mRNA stability. To exclude this possibility, we used an [$^{35}S$]-methionine prokaryotic cell-free protein synthesis system in vitro in the presence of purified YhaV, and two C-terminal truncated forms of this protein (YhaV-L and YhaV-S). Our results suggest that the YhaV C-terminal region is essential for mRNA interferase activity, and the W143 or H154 residues may play an analogous role to Y87 of RelE.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.56-61
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• 2015

Ideal and stretch-out C-V curve were shown at high frequency using SiGe p-FinFET simulation. Average interface trap density can be extracted by the difference of voltage axis on ideal and stretch-out C-V curve. Also, interface trap density(Dit) was extracted by Terman's method that uses the same stretch-out of C-V curve with interface trap characteristic, and average interface trap density was calculated at same energy level. Comparing the average interface trap density, which was found by method using difference of voltage, with Terman's method, it was verified that the two methods almost had the same average interface trap density.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.

• Herbal Formula Science
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• v.12 no.1
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• pp.209-223
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• 2004

Objective: This study was conducted to investigate the effects of Coptidis Rhizoma on the plasma IL-6 and $TNF-{\alpha}$ level in mice by intracerebroventricular(I.C.V.) injection of Lipopolysaccharide (LPS). Method: 6 mice were assigned to each of the Normal group, the Control group, and the individual Experimental groups. In the Normal group only saline was administered intragastrically, and in the Control group LPS was injected intracerebroventricularly 1 hr after intragastric administration of saline. In the Experimental groups Coptidis Rhizoma(0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS (100ng/mouse) I.C.V. Injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital venous plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of plasma IL-6 and $TNF-{\alpha}$. Result: 1. LPS I.C.V. Injection increased plasma IL-6 level significantly in a dose-dependent manner compared with Normal group. (P<0.01) The plasma IL-6 concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 2. Both the 0.5g/kg(Sample A) and 1.0g/kg(Sample B) groups to which Coptidis Rhizoma was administered intragastrically 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed insignificant lower plama IL-6 level in 1 hr than Control group(P>0.05), and 3.0g/kg group(Sample C) conversely showed higher plama IL-6 level than Control group. 3. LPS I.C.V. Injection increased plasma $TNF-{\alpha}$ level significantly in a dose-dependent manner compared with Normal group.(P<0.05) The plasma $TNF-{\alpha}$ concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 4. All Sample groups(0.5g/kg, 1.0g/kg, and 3.0g/kg) to which Coptidis Rhizoma was administered intragastrically with each constituent-dose 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed significant lower $TNF-{\alpha}$ plama level in 1 hr than Control group.(P<0.001) These data revealed that Coptidis Rhizoma might have anti inflammatory effect by reducing the plasma $TNF-{\alpha}$ level in a dose dependent manner in mice LPS I.C.V. Injection.

• Journal of the Korean Society for Heat Treatment
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• v.30 no.2
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• pp.43-52
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• 2017

Heat treatment condition for dissolution of the M23C6 carbides in 2.25Cr-1Mo-V-Ti material for thermal power plant tube was investigated using a dilatometer method. 2.25Cr-1Mo-V-Ti material was heat-treated at $900{\sim}1,100^{\circ}C$ for 0, 10, 30 min to find the proper dissolution condition of M23C6 carbides. The phase identification and volume fraction of the carbide were measured by using OM, SEM, EBSD and TEM analysis. Optimal heat treatment condition of M23C6 carbide dissolution was selected by predicting dissolution temperature of carbide using Bs points appeared at dilatometer curve. Experimental results showed that the conditions of carbide dissolution was 900, 1,000, $1,100^{\circ}C$ for 30 min. Eventually, the optimal heat treatment condition for dissolution was 30 min at $1,000^{\circ}C$ considering the minimum coarsening of Austenite grain size.

• Journal of Sensor Science and Technology
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• v.8 no.6
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• pp.448-453
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• 1999

A Pd-SiC Schottky diode for detection of hydrogen gas operating at high temperature was explored. Hydrogen-sensing behaviors of Pd-SiC Schottky diode were analyzed as a function of hydrogen concentration and temperature by I-V and ${\Delta}I$-t methods under steady-state and transient conditions. The effect of hydrogen adsorption on the barrier height was investigated. Analysis of the steady-state kinetics using I-V method confirmed that the atomistic hydrogen adsorption process is responsible for the barrier height change in the diode.