• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.117.2-117
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• 2003

The importance and diversity of the genus Stemphylium highlights the need for accurate identification of species. However, many Stemphylium isolates have been misidentified due to the use of spore size as the only identifying character. Molecular phylogenetic analyses were performed on fifty-four isolates covering 9 Stemphylium species collected in Korea. Phylogenetic analysis of the translation elongation factor -1 alpha (EF-1) and the calmodulin gene sequence data showed that Stemphylium species were segregated into seven distinct groups, most of w hichcorrelated with species identified by morphology. Analysis of EF-1 in particular was useful for establishing well- supported relationships among the species of Stemphylium.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.224-230
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• 1986

Dodecyltrimethylammonium bromide (DTAB) was examined as a counter-ion in the separation of aromatic sulfonic acids on alkylmodified silica (ODS) column by reversed-phase ion-pair chromatography. The capacity factor of acids was investigated and separation was attempted. The capacity factor of samples was influenced by the several factors such as a concentration of counter-ion, concentration of methanol, kinds and concentration of electrolyte in mobile phase as well as kinds and position of functional group in samples. Some mixtures of samples were able to be separated under optimum condition.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.128-131
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• 2017

We explore the inverse electron demand Diels-Alder reactions of tetrazines with various functional groups employing quantum calculations. In general, the rate of inverse electron demand Diels-Alder reaction depends on molecular orbital levels of electron donor and electron acceptor. Likewise, ${\pi}$ orbital of the dienophile and ${\pi}^*$ orbital of the diene is a key factor. In this work, we discuss the case where the energy of diene's ${\pi}^*$ molecular orbital is not the sole governing factor to determine the reaction rate, rather the rate shows strong correlation with the charge density of dienes.

• Journal of the Korean Chemical Society
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• v.63 no.1
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• pp.45-50
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• 2019

Because arsenic (As) is a chemical substance toxic to humans, there have been extensive investigations on the development of As detection methods. In this study, the electrochemical determination of As on nanoporous gold (NPG) electrodes was investigated using anodic stripping voltammetry. The electrochemical surface area of the NPG electrodes was controlled by changing the reaction times during the anodization of Au for NPG preparation, and its effect on the electrochemical behavior during As detection was examined. The detection efficiency of the NPG electrodes improved as the roughness factor of the NPG electrodes increased up to around 100. A further increase in the surface area of the NPG electrodes resulted in a decrease of the detection efficiency due to high background current levels. The most efficient As detection efficiency was obtained on the NPG electrodes prepared with an anodization time of 50 s. The effects of the detection parameters and of the Cu interference in As detection were investigated and the NPG electrode was compared to flat Au electrodes.

• Analytical Science and Technology
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• v.9 no.4
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• pp.406-410
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• 1996

The adsorption behaviors of transition metal ions on the poly(N,N'-bispalmitoyl-1, 12-diaza-3, 4;9,10-dibenzo-5,8-cyclopentadecane) has been determined by adsorption process in aqueous solution. The order of concentration factor(CF) and the amount of adsorption were Cu(II)

• Archives of Pharmacal Research
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• v.28 no.12
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• pp.1345-1349
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• 2005

Six phenolic constituents, 2-methoxybenzyl benzoate (1), negletein (2), 2',3'-dihydroxy-4',6'­dimethoxydihydrochalcone (3), 5,6-dihydroxy-7-methoxy-dihydroflavone (4), astilbin (5), and quercitrin (6) were isolated from the methanol extract of the dried leaves of Desmos chinensis. Their structures were elucidated from spectral and chemical data. Of these constituents, compounds 2 ($IC_{50}$: 3.89 $\pm$ 0.39 $\mu$M) and 3 ($IC_{50}$: 9.77 $\pm$ 0.26 $\mu$M) exhibited potent inhibitory activity against nuclear factor of activated T cells (NFAT) transcription factor, and compound 1 ($IC_{50}$: 28.4 $\pm$ 2.62 $\mu$M) exhibited moderate inhibitory activity.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.46-46
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• 2004

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1973-1979
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• 2007

Novel organic dyes, JK-34, JK-35 and JK-36 containing bis-dimethylfluorenyl amino coumarin unit are designed and synthesized. Nanocrystalline TiO2 dye-sensitized solar cells were fabricated using these dyes. Under standard global AM 1.5 solar condition, the JK-34 sensitized cell gave a short circuit photocurrent density of 10.05 mA cm?2, open circuit voltage of 0.65 V, and a fill factor of 0.68, corresponding to an overall conversion efficiency η of 4.54%. We found that the power conversion efficiency was shown to be quite sensitive to the structural modifications of bridging thiophene moiety.

• BMB Reports
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• v.56 no.8
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• pp.445-450
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• 2023

The development of atherosclerotic cardiovascular disease is associated with the phenotypic switching of vascular smooth muscle cells (SMCs) from a contractile to a synthetic state, leading to cell migration and proliferation. Platelet-derived growth factor-BB (PDGF-BB) modulates this de-differentiation by initiating a number of biological processes. In this study, we show that gene expression of hyaluronic acid (HA) and proteoglycan link protein 1 (HAPLN1) was upregulated during differentiation of human aortic SMCs (HASMCs) into a contractile state, but downregulated upon during PDGF-BB-induced dedifferentiation. This is the first study showing that the treatment of HASMCs with full-length recombinant human HAPLN1 (rhHAPLN1) significantly reversed PDGF-BB-induced decrease in the protein levels of contractile markers (SM22α, α-SMA, calponin, and SM-MHC), and inhibited the proliferation and migration of HASMCs induced by PDGF-BB. Furthermore, our results show that rhHAPLN1 significantly inhibited the phosphorylation of FAK, AKT, STAT3, p38 MAPK and Raf mediated by the binding of PDGF-BB to PDGFRβ. Together, these results indicated that rhHAPLN1 can suppress the PDGF-BB-stimulated phenotypic switching and subsequent de-differentiation of HASMCs, highlighting its potential as a novel therapeutic target for atherosclerosis and other vascular diseases.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.16-26
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• 2017

Auxin response factor (ARF) and Aux/IAA transcriptional repressor family proteins play a major role in auxin's signalling process. Using the GALAXY protein modelling programs, monomer, dimer and oligomer structures of Aux/IAA17 and ARF5 protein were predicted based on the known experimental structures. By analysing the proposed complex structures, key interacting residues on binding site could be determined, and further suggestions for experimental studies were made.