• Journal of Information Technology Applications and Management
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• v.11 no.1
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• pp.137-159
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• 2004

In the past days, most of studies about website and Online behavior have been mainly focused on the adoption of website and internet shopping or internet shopping mall. But the model of website revisit behavior has not been made and the leading theory of website usage behavior has not been existed. Lately, many researches on commercial website revisiting behavior are emphasizing the role of intention, attitude, satisfaction in online visiting behavior such as Jarvenpaa et al. [1997, 1999, 2000], Wang et al. [2001], Moon & Kim [2001], Heijden[2003], Sultan et al. [2002], Yoon [2000], Shankar et al. [2002a, 2002b], Mcknight et al. [2002], Chen & Dhillon [2003] and so on. The purpose of this paper is two-folds. The one is to find the affecting factors on the website users' revisit behavior in commercial website and the other is to search more influencing ones on the determinant factors, to analyze research model using in LISREL. The EFA and reliability test was executed by for finding the validity and reliability, covariance matrix analysis was executed for the purpose of testing the 13 hypotheses. The major finding of this paper would be summarized as followed : (1) The roles of satisfaction and attitude to the revisit behavior are very important and both variables have determining effects in commercial website revisit behavior. (2) The determining factors in positively affecting website users' satisfaction are attitude, perceived usefulness, design. (3) The determining factors in positively affecting website users' attitude are perceived usefulness, design, perceived ease of use, and negatively affecting factor was perceived risk in website.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2903-2908
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• 2010

Protein S-nitrosation is common in cells under nitrosative stress. In order to model proteins with S-nitrosocysteine (CysSNO) residues, we first developed an Amber force field for S-nitrosoethanethiol (EtSNO) and then transferred it to CysSNO. Partial atomic charges for EtSNO and CysSNO were obtained by a restrained electrostatic potential approach to be compatible with the Amber-99 force field. The force field parameters for bonds and angles in EtSNO were obtained from a generalized Amber force field (GAFF) by running the Antechamber module of the Amber software package. The GAFF parameters for the CC-SN and CS-NO dihedrals were not accurate and thus determined anew. The CC-SN and CS-NO torsional energy profiles of EtSNO were calculated quantum mechanically at the level of B3LYP/cc-pVTZ//HF/6-$31G^*$. Torsional force constants were obtained by fitting the theoretical torsional energies with those obtained from molecular mechanics energy minimization. These parameters for EtSNO reproduced, to a reasonable accuracy, the corresponding torsional energy profiles of the capped tripeptide ACE-CysSNO-NME as well as their structures obtained from quantum mechanical geometry optimization. A molecular dynamics simulation of myoglobin with a CysSNO residue produced a well-behaved trajectory demonstrating that the parameters may be used in modeling other S-nitrosated proteins.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.2
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• pp.123-134
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• 2022

In this study, the whitening and antioxidant effects of the extracts from Hydrangea petiolaris (H. petiolaris) leaves was confirmed, and the chemical structure was identified by separating the active ingredients. In the whitening tests using α-MSH stimulated B16F10 melanoma cells, the n-hexane (Hex) fraction inhibited the cellular melanogenesis and intracellular tyrosinase activities without causing cell toxicity. In addition, the Hex fraction reduced expression of tyrosinase and TRP-2 protein. Upon the anti-oxidative studies by DPPH and ABTS⁺ radicals, potent radical scavenging activities were observed in the ethyl acetate (EtOAc) fraction. Also, for the cellular protective effects on HaCat keratinocytes damaged by H₂O₂, the EtOAc fraction indicated protective effects against oxidative stress. Eight phytochemicals were isolated from the extract of H. petiolaris leaves; ethyl linoleate (1), ethyl linolenate (2), 1-linoleoyl glycerol (3), 1-linolenoyl glycerol (4), epi-catechin (5), afzelin (6), quercitrin (7), hyperin (8). Among the isolates, the compounds 5 - 8 showed DPPH and ABTS⁺ radical scavenging activities. The contents of quercitirin, a major isolated in this extract, determined by HPLC analysis were confirmed to be about 31.3 mg/g for the 70% ethanol extract and 169.8 mg/g for the EtOAc fraction. Based on these results, it was suggested that the extract from H. petiolaris leaves could be potentially applicable as whitening and anti-oxidative ingredients in cosmetic formulations.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.395-405
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• 2017

To confirm potential anti-cancer activities of ethylacetate (EtOAc) fraction from Orostachys japonicus on the A549 human lung cancer cells, this study examined. As a result of conducting MTS assay for measuring cell viability, the EtOAc fraction inhibited the proliferation of A549 cells in a dose-dependent manner. To investigate whether the inhibiting A549 cell viability was caused by apoptosis, this study analyzed chromatin condensation in A549 cells using DAPI staining. The morphological changes such as the formation of nuclear condensation were formed in a dose-dependent manner. Also, this study performed Annexin V-FITC staining for detecting phosphatidylinositol (PS). As a result of Annexin V-FITC staining to investigate level of early and late apoptosis, the apoptosis level treated with EtOAc fraction was higher than that of control. RT-PCR was performed to study the correlation between G2/M cell cycle arrest and cell cycle control genes. The anti-cancer activity of EtOAc fraction was accompanied by inhibition of CDK1, 4, cyclin B1 and D1 mRNA. This study also examined the expression of various marker proteins: p53, Bax, Bcl-2 and pro-caspase 3. Western blotting revealed that p53 and Bax proteins were up-regulated, and Bcl-2 and pro-caspase 3 proteins down-regulated in a time and dose-dependent manner.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.420-425
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• 2010

The antifungal effects and action mechanisms of styraxjaponoside A and B were investigated. Devoid of hemolytic effect, the compounds had significant effect against several human pathogenic fungal strains, with energy-independent manners. To understand the action mechanisms of the compounds, the flow cytometric analysis plotting the forward scatter and the side scatter, $DiBAC_4$(3) staining and DPH fluorescence analysis were conducted. The results indicated that the actions of the compounds were dependent upon the membrane-active mechanisms. The present study suggests that styraxjaponoside A and B exert their antimicrobial effects via membrane-disruptive mechanisms.

• Korean Journal of Plant Taxonomy
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• v.34 no.3
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• pp.265-271
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• 2004

A new species of Corydalis sect. Corydalis (Fumariaceae), C. namdoensis B.U. Oh et J.G. Kim, is described from the central and southern part of Korea. The new species is distinct from its close relative C. albipetala in having very variable leaf shapes, broadly flattened fusiform fruits, seed arrangement nearly in two rows in capsule, V-shaped inner petal apex and limited distribution area.

• Analytical Science and Technology
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• v.6 no.4
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• pp.349-357
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• 1993

Analytical methods of thromboxane $B_2(TXB_2)$ using various techniques of Fast Atom Bombardment mass spectrometry (FAB MS) were studied, static FAB condition was investigated to obtain linear response curve using docosanoic acid as a internal standard. For maximum sensitivity, a continuos-flow(CF-) FAB MS by selected-ion monitoring(SIM) with devised sample introduction system, has been developed to quantiate thromboxane $B_2$ in biological sample. Instrumental parameters affecting sensitivity, reproducibility has been studied. The method has been optimized with respect to the eluent, 0.75% glycerol(in EtOH v/v) and flow rate of $3.7{\mu}l/min.$ Under the condition, detection limits were below 10pg in SIM mode and a good linear relationship between dose and response was achieved.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.495-504
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• 2008

Evapotranspiration (ET) is an important state variable while simulating daily streamflow in hydrological models. In the estimation of ET, for example, when using FAO Penman Monteith equation, the LAI (Leaf Area Index) value reflecting the conditions of vegetation generally affects considerably. Recently in evaluating the vegetation condition as a fixed quantity, the remotely sensed LAI from MODIS satellite data is available, and the time series values of spatial LAI coupled with land use classes are utilized for ET evaluation. Four years (2001-2004) of MODIS LAI was prepared for the evaluation of Penman Monteith ET in the continuous hydrological model, SLURP (Semi-distributed Land Use-based Runoff Processes). The model was applied for simulating the dam inflow of Chungju watershed ($6661.3km^2$) located in the upstream of Han river basin. For four years (2001-2004) dam inflow data and meteorological data, the model was calibrated and verified using MODIS LAI data. The average Nash-Sutcliffe model efficiency was 0.66. The 4 years watershed average Penman Monteith ETs of deciduous, coniferous, and mixed forest were 639.1, 422.4, and 631.6 mm for average MODIS LAI values of 3.64, 3.50, and 3.63 respectively.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.1
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• pp.116-134
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• 2005

Although the parallel prescription of Sopoongsangagambang (SG) administration along with external treatment such as spraying or ointment application on the skin is clinically used for the treatment of atopic dermatitis (AD), molecular mechanism underlying its effectiveness is unknown. Thus in the present study, diverse immune responses in terms of chemical mediators related to AD were investigated using an atopic mouse model NC/Nga after SG administration and external treatment (ET), and major findings are summarized as follows. 1. The clinical severities in 16 and 20 week old NC/Nga mice with SG and ET treatment were decreased to 72.2% and 62.3% respectively compared to the control NC/Nga mice with no drug treatment. 2. IgE, IL-4, IL-5, IL-6, IL-13, IgM, IgG1 and IgG2a levels in the serum of SG and ET treated NC/Nga mouse group were significantly decreased compared to the untreated control mice. In contrast, $IFN-{\gamma}$ showed a significant increase in the experimental group compared to the untreated control group. 3. The spleen weight of SG and ET treated NC/Nga mice was significantly decreased compared to the untreated control group. 4. The B/T ratio in the lymph node of SG and ET treated NC/Nga mice was increased compared to the untreated control group. $CD4^+\;and\;CD8^+$ cell numbers in the lymph node of SG and ET treated NC/Nga mice were significantly increased compared to the untreated control group, but $CD69^+\;and\;CD11a^+$ cells were significantly decreased. 5. mRNA expression levels of IL-4, IL-5, and CCR3 in the skin tissues of SG and ET treated NC/Nga mice were significantly decreased, and expression levels of IL-6, IL-13, $CD69^+/CD3{\varepsilon}^+\;and\;CD19^+/CD44^+$ in the skin tissues of SG and ET treated NC/Mga mice were significantly decreased compared to the untreated control group. $IFN-{\gamma}$ mRNA expression levels were increased compared to the untreated control group. 6. Histological observation of the ear and neck skin tissues showed that the extents of inflammation and infiltrated immune cells in the epidermis and dermis of SG and ET treated NC/Nga mice were highly reduced compared to the untreated control group. 7. Lymphokine assay showed a significant decrease in IL-4 levels in SG and ET treated NC/Nga mice compared to the untreated control group, but the levels of $IFN-{\gamma}$ secretion were significantly increased drug treated NC/Nga mice.