• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1204-1207
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• 2009

We investigated the device performance of bulk heterojunction solar cells depending on the active layer thickness. For the systematic comparison, the polymer solar cells comprising RR-P3HT:PCBM (1:0.8 (wt%:wt%)) blend films with different thickness were characterized by impedance spectroscopy, and J-V measurement in dark and solar simulated illumination. The device with 120 nm thickness of active layer exhibited maximum power conversion efficiency of 3.5 % under AM 1.5 100mW/$cm^2$ illumination condition.

• Molecules and Cells
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• v.26 no.3
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• pp.228-235
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• 2008

Thiol-dependent redox systems are involved in regulation of diverse biological processes, such as response to stress, signal transduction, and protein folding. The thiol-based redox control is provided by mechanistically similar, but structurally distinct families of enzymes known as thiol oxidoreductases. Many such enzymes have been characterized, but identities and functions of the entire sets of thiol oxidoreductases in organisms are not known. Extreme sequence and structural divergence makes identification of these proteins difficult. Thiol oxidoreductases contain a redox-active cysteine residue, or its functional analog selenocysteine, in their active sites. Here, we describe computational methods for in silico prediction of thiol oxidoreductases in nucleotide and protein sequence databases and identification of their redox-active cysteines. We discuss different functional categories of cysteine residues, describe methods for discrimination between catalytic and noncatalytic and between redox and non-redox cysteine residues and highlight unique properties of the redox-active cysteines based on evolutionary conservation, secondary and three-dimensional structures, and sporadic replacement of cysteines with catalytically superior selenocysteine residues.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.72-72
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• 2020

Various mixtures were prepared depending on the mixing ratio of Scutellaria baicalensis hot water extract (SB-HW) and Chrysanthemum morifolium ethanol extract (CM-E) and their anti-inflammatory activity were compared. Among them, SB-HW (80 ㎍/mL)/CM-E (120 ㎍/mL) or SB-HW (40 ㎍/mL)/CM-E (160 ㎍/mL) significantly inhibited LPS-stimulated NO and IL-6 levels in RAW 264.7 cells. The SB-HW (80 ㎍/mL)/CM-E (120 ㎍/mL) mixture, which was determined as active mixture, significantly reduced MUC5AC secretion in PMA and LPS-induced NCI-H292 cells. The active mixture also reduced the production of PGE2 and IL-8 in PMA-induced A549 cells. LC-MS/MS analysis showed that the active mixture was composed of high contents of flavone glycosides, such as baicalin and cynaroside. Western blot analysis indicated that the active mixture suppressed phosphorylation of ERK, JNK, and p38, associating with the inhibition of MAPK signaling. Taken together, our results suggest that the active mixture could be applied as a new anti-inflammatory herbal medicine

• Journal of Ginseng Research
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• v.46 no.6
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• pp.759-770
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• 2022

Background: Aerobic cellular respiration provides chemical energy, adenosine triphosphate (ATP), to maintain multiple cellular functions. Sirtuin 1 (SIRT1) can deacetylate peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) to promote mitochondrial biosynthesis. Targeting energy metabolism is a potential strategy for the prevention and treatment of various diseases, such as cardiac and neurological disorders. Ginsenosides, one of the major bioactive constituents of Panax ginseng, have been extensively used due to their diverse beneficial effects on healthy subjects and patients with different diseases. However, the underlying molecular mechanisms of total ginsenosides (GS) on energy metabolism remain unclear. Methods: In this study, oxygen consumption rate, ATP production, mitochondrial biosynthesis, glucose metabolism, and SIRT1-PGC-1α pathways in untreated and GS-treated different cells, fly, and mouse models were investigated. Results: GS pretreatment enhanced mitochondrial respiration capacity and ATP production in aerobic respiration-dominated cardiomyocytes and neurons, and promoted tricarboxylic acid metabolism in cardiomyocytes. Moreover, GS clearly enhanced NAD⁺-dependent SIRT1 activation to increase mitochondrial biosynthesis in cardiomyocytes and neurons, which was completely abrogated by nicotinamide. Importantly, ginsenoside monomers, such as Rg1, Re, Rf, Rb1, Rc, Rh1, Rb2, and Rb3, were found to activate SIRT1 and promote energy metabolism. Conclusion: This study may provide new insights into the extensive application of ginseng for cardiac and neurological protection in healthy subjects and patients.

• BMB Reports
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• v.32 no.6
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• pp.547-553
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• 1999

Aminoacyl-tRNA synthetases are essential enzymes catalyzing the attachment of specific amino acids to cognate tRNAs. In the present work, the substrate analogue L-methionine hydroxamate was used to identify functional residues located in the active site of the E. coli methionyl-tRNA synthetase (MetRS). This compound inhibited bacteria, yeast, and human MetRS activities to a similar degree, suggesting a conserved active site structure and mechanism between MetRSs of different phylogenetic domains. Mutants of the E. coli MetRS resistant to methionine hydroxamate were also isolated. These mutants contained a substitution either at T10, Y15, or Y94. These residues are highly conserved among the different MetRSs and the mutants showed decreased aminoacylation activity, suggesting their functional and structural significances. The putative roles of these residues are discussed on a structural basis.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.609-613
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• 2005

Advanced mobile communication devices require a bright, high information content display in a small, light-weight, low power consumption package. In this paper we will outline our progress towards developing such a low power consumption active-matrix flexible OLED ($FOLED^{TM}$) display. Our work in this area is focused on three critical enabling technologies. The first is the development of a high efficiency long-lived phosphorescent OLED ($PHOLED{TM}$) device technology, which has now proven itself to be capable of meeting the low power consumption performance requirements for mobile display applications. Secondly, is the development of flexible active matrix backplanes, and for this our team are employing poly-Si TFTs formed on metal foil substrates as this approach represents an attractive alternative to fabricating poly-Si TFTs on plastic for the realization of first generation flexible active matrix OLED displays. Unlike most plastics, metal foil substrates can withstand a large thermal load and do not require a moisture and oxygen permeation barrier. Thirdly, the key to reliable operation is to ensure that the organic materials are fully encapsulated in a package designed for repetitive flexing. We also present progress in operational lifetime of encapsulated T-PHOLED pixels on planarized metal foil and discuss PHOLED encapsulation strategy.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1131-1140
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• 2016

A simple design for a sliding mode observer is proposed for EV lithium battery SOC estimation in this paper. The proposed observer does not have the limiting conditions of existing observers. Compared to the design of previous sliding mode observers, the new observer does not require a solving matrix equation and it does not need many observers for all of the state components. As a result, it is simple in terms of calculations and convenient for engineering applications. The new observer is suitable for both time-variant and time-invariant models of battery SOC estimation, and the robustness of the new observer is proved by Liapunov stability theorem. Battery tests are performed with simulated FUDS cycles. The proposed observer is used for the SOC estimation on both unchanging parameter and changing parameter models. The estimation results show that the new observer is robust and that the estimation precision can be improved base on a more accurate battery model.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.793-796
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• 2005

A structure and a design of device were developed to fabricate large-scale active matrix organic light-emitting diode (AMOLED) display with good color purity and high aperture ratio. With these technologies, we developed a full color 14.1 inch WXGA AMOLED display. For the integration of OLED on an active matrix a-Si TFT backplane, an efficient top emission OLED is essential since the TFT circuitry covers a large position of the pixel aperture. These technologies will enable up the OLED applications to larger size displays such as desktop monitors and TVs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6804-6809
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• 2014

This paper presents a bandpass filter using a current differencing transconductance amplifier (CDTA)s for application to low-voltage and low-power analog signal processing systems. The presented filter employs grounding and floating active inductors, which are composed of two or three CDTAs, and is capable of realizing all the standard functions of the filter without requiring any component matching criteria or extra active components. The HSPICE simulation result of the designed active bandpass filter showed that it had a 10MHz center frequency with -2.5dB attenuated bandwidth from 9.5 MHz to 10.5 MHz, and -50dB from 8 MHz to 17 MHz.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.1-11
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• 1975

The present experiments were carried out to investigate the active center of sodium and potassium ion activated adenosine triphosphatase. An ATPase, activated by sodium ion Plus potassium ion in the presence of magnesium ion, and inhibited by ouabain, has been obtained from rabbit red cell ghosts. The ATPase activity was measured by inorganie phosphate released from ATP. From this values of the measured inorganic phosphate, the activity of ATPase was calculated. The following results were observed. 1. The activity of $(Na^++K^+)-ATPase$ is inhibited by ouabain. This effect may not be due to an effect on sulfhydryl groups, amino groups, carboxyl groups, imidazole groups and hydroxyl groups. 2. The $(Na^++K^+)$-activated enzyme system is inhibited by p-chloromercuribenzoate and by d nitroflurobenzene, and this effect may be due to an effect on sulfhydryl groups. These results indicate that the sulfhydryl groups is attached to sodium-potassium dependent adenosine triphosphate, an aspect of the pump. 3. The $(Na^++K^+)-activated$ enzyme system is inhibited by maleic anhydride and this inhibition is reversed by lysine. This Seems to indicate that the active center of this enzyme is the amino groups. 4. The $(Na^++K^+)$-activated enzyme system is inhibited by iodoacetamide and this inhibition is reversed by the simultaneous present of cysteine and aspartic acid in the suspension medium. This result indicates that this enzyme contains sulfhydryl groups and carboxyl groups. 5. The $(Na^++K^+)-ATPase$ activity is accelerated by adrenaline and this effect is abolished by aspartic acid. This effect of aspartic acid indicate that carboxyl group might be involved in the hydrolysis of ATP by the enzyme system. On the hydrolysis of ATP by the enzyme system. On the basis of these experiments it f·as suggested that the active center of $(Na^++K^+)-activated$ ATPase contains sulfhydryl groups, amino groups and carboxyl groups.