Evaluation of e-commerce websites using fuzzy hierarchical TOPSIS based on E-S-QUAL

Kang, D.,Jang, W.,Park, Y. Elsevier Science, B.V 2016 Applied soft computing Vol.42 No.-

<P>In the wake of the rapid emergence of e-commerce, its evaluation is of great theoretical and practical importance. Among the various types of e-commerce, business-to-consumer (B2C) e-commerce has become a key, and especially influential, retailing channel. Its ascendancy raises core issues with respect to how the customer is to be satisfied by, and therefore inclined to trust, e-commerce websites. B2C e-commerce website evaluation, therefore, is an important related issue. First, while a number of studies have studied B2C e-commerce website evaluation using various multiple-criteria-decision-making (MCDM) methods, they have focused only on the perceived service quality of B2C e-commerce websites. In fact, it is generally recognized that service quality is determined by the difference between the expected service level (which expectation is derived from information obtained before the service experience) and the actual, perceived service level; this concept, then, should be also be afforded due consideration in B2C e-commerce website evaluation. Second, among the various MCDM approaches, TOPSIS, which involves the consideration of both the positive-ideal solution (PIS) and the negative-ideal solution (NIS), is especially pertinent to the complex decision-making entailed in the evaluation of B2C e-commerce websites. Third, the human element of subjectivity in the evaluation of B2C e-commerce websites needs to be considered in order to enable modeling of real-life website-evaluation situations. Finally, the hierarchical structure of the evaluation criteria between the main dimensions and their sub-criteria should be considered. To reflect these issues, in this paper, we present a fuzzy hierarchical TOPSIS based on E-SERVQUAL (E-S-QUAL). This approach effectively considers the raised issues and preserves the core concept of E-S-QUAL (the extended version of SERVQUAL) for measurement of electronic service quality in the e-commerce environment. The empirical case study of B2C e-commerce provides the researchers and practitioners to understand in a better way the evaluation process from a practical point of view. In addition, core finding of this study is that the comparison results with other MCDM methods further verify the robustness of the proposed approach. It implies that this method potentially can be applied to performance evaluation of similar service sectors. (C) 2016 Published by Elsevier B.V.</P>

NF-κB signaling is key in the wound healing processes of silk fibroin

Park, Ye Ri,Sultan, Md. Tipu,Park, Hyun Jung,Lee, Jung Min,Ju, Hyung Woo,Lee, Ok Joo,Lee, Dong Jin,Kaplan, David L.,Park, Chan Hum Elsevier Science B.V. Amsterdam 2018 ACTA BIOMATERIALIA Vol. No.

<P><B>Abstract</B></P> <P>Silk fibroin (SF) is a well-studied biomaterial for tissue engineering applications including wound healing. However, the signaling mechanisms underlying the impact of SF on this phenomenon have not been determined. In this study, through microarray analysis, regulatory genes of NF-ĸB signaling were activated in SF-treated NIH3T3 cells along with other genes. Immunoblot analysis confirmed the activation of the NF-ĸB signaling pathway as SF induced protein expression levels of IKKα, IKKβ, p65, and the degradation of IκBα. The treatment of NIH3T3 cells with SF also increased the expression of cyclin D1, vimentin, fibronectin, and vascular endothelial growth factor (VEGF). The expression of these factors by SF treatment was abrogated when NF-ĸB was inhibited by a pharmacological inhibitor Bay 11-7082. Knockdown of NF-ĸB using siRNA of IKKα and IKKβ also inhibited the SF-induced wound healing response of the NIH3T3 cells in a wound scratch assay. Collectively, these results indicated that SF-induced wound healing through the canonical NF-κB signaling pathway via regulation of the expression of cyclin D1, vimentin, fibronectin, and VEGF by NIH3T3 cells. Using an <I>in vivo</I> study with a partial-thickness excision wound in rats we demonstrated that SF-induced wound healing via NF-κB regulated proteins including cyclin D1, fibronectin, and VEGF. The <I>in vitro</I> and <I>in vivo</I> data suggested that SF induced wound healing via modulation of NF-ĸB signaling regulated proteins.</P> <P><B>Statement of Significance</B></P> <P>Silk fibroin has been effectively used as a dressing for wound treatment for more than a century. However, mechanistic insight into the basis for wound healing via silk fibroin has not been elucidated. Here we report a key mechanism involved in silk fibroin induced wound healing both <I>in vitro</I> and <I>in vivo.</I> Using genetic- and protein-level analyses, NF-κB signaling was found to regulate silk fibroin-induced wound healing by modulating target proteins. Thus, the NF-κB signaling pathway may be utilized as a therapeutic target during the formulation of silk fibroin-based biomaterials for wound healing and tissue engineering.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Color-stable, ITO-free white organic light-emitting diodes with enhanced efficiency using solution-processed transparent electrodes and optical outcoupling layers

Chang, H. W.,Kim, Y. H.,Lee, J.,Hofmann, S.,Lussem, B.,Muller-Meskamp, L.,Gather, M. C.,Leo, K.,Wu, C. C. Elsevier Science B.V., Amsterdam. 2014 Organic electronics Vol.15 No.5

In this work, we demonstrate color-stable, ITO-free white organic light-emitting diodes (WOLEDs) with enhanced efficiencies by combining the high-conductivity conducting polymer PEDOT:PSS as transparent electrode and a nanoparticle-based scattering layer (NPSL) as the effective optical out-coupling layer. In addition to efficiency enhancement, the NPSL is also beneficial to the stabilization of electroluminescent spectra/colors over viewing angles. Both the PEDOT:PSS and the NPSL can be fabricated by simple, low-temperature solution processing. The integration of both solution-processable transparent electrodes and light extraction structures into OLEDs is particularly attractive for applications since they simultaneously provide manufacturing, cost and efficiency advantages. (C) 2014 Elsevier B.V. All rights reserved.

Study on antidiabetic activity of wheat and barley starch using asymmetrical flow field-flow fractionation coupled with multiangle light scattering

Dou, H.,Zhou, B.,Jang, H. D.,Lee, S. Elsevier Science B.V., Amsterdam. 2014 Journal of chromatography A Vol.1340 No.-

<P>The ability of asymmetrical flow field-flow fractionation (AF4) coupled online with multiangle light scattering (MALS) and refractive index detector (RI) (AF4-MALS-RI) for monitoring of change in molecular conformation of wheat and barley starch during germination process was evaluated. AF4 provides separation of starch molecules based on their hydrodynamic sizes, and MALS yields the molar mass and molecular size (radius of gyration, R-g). In vitro and in vivo anti-hyperglycemic effect of germinated wheat and barley was studied. The relationship between antidiabetic activity and molecular conformation was, for the first time, investigated. The ratio of Rg to the hydrodynamic radius (Rh) and the apparent density were proven to be important parameters as they offer an insight into molecular conformation. Results showed that, when geminated, the apparent density and the antidiabetic activity of barley were significantly increased, suggesting germination makes the molecules more compact which could contribute to enhancement of their antidiabetic activity. The information obtained by AF4-MALS-RI is valuable for understanding of germination mechanism, and thus for developing functional foods. (C) 2014 Elsevier B.V. All rights reserved.</P>

Two stage deformation modeling for DP 780 steel sheet using crystal plasticity

Verma, R. K.,Biswas, P.,Kuwabara, T.,Chung, K. Elsevier Science B.V., Amsterdam. 2014 Materials science & engineering. properties, micro Vol.604 No.-

Proper analysis of non-proportional plastic deformation is important for the successful prediction of failure and springback in sheet metal forming of ultra-high strength steels. In this work, a crystal plasticity finite element was applied to analyze the two-stage deformation behavior of a dual phase (DP 780) steel. It was found to be possible to predict the cross-effect observed during the two-stage deformation fairly accurately using the model. It was further felt that accounting for the path dependency of dislocation evolution would still improve the simulation accuracy. (C) 2014 Elsevier B.V. All rights reserved.

Self-templated synthesis of hollow silica microspheres using Na2SiO3 precursor

Yoo, B. U.,Han, M. H.,Nersisyan, H. H.,Yoon, J. H.,Lee, K. J.,Lee, J. H. Elsevier Science B.V., Amsterdam. 2014 Microporous and mesoporous materials Vol.190 No.-

A facile synthesis method has been developed to directly convert solid Na2SiO3 hollow microspheres into non-aggregated hollow SiO2 microspheres at ambient pressure and temperature. An initial dispersion of Na2SiO3 microspheres (mean diameter: 10-50 mu m) in ethanol was prepared, and subsequent hydrolysis of Na2SiO3 was performed using a HCl solution. Other precipitants such as ammonium salts (NH4Cl, (NH4)(2)SO4) and boron oxide (B2O3) were also tested. The characteristics of the synthesized hollow microspheres were investigated in detail by thermogravimetric analysis, field emission scanning electron microscopy, N-2 adsorption-desorption isotherms, and X-ray diffraction. The as-prepared SiO2 microspheres were hollow with diameters between 10 and 50 mu m. The surface area of these microspheres, determined by Brunauer-Emmett-Teller analysis, was in the range 193-288 m(2) g(-1). Using the proposed method, the size and shape of the obtained silica microspheres are largely determined by the size of low-cost and environmentally friendly precursor sodium silicate microspheres. (C) 2014 Elsevier Inc. All rights reserved.

Simultaneous determination of nine bioactive compounds in Yijin-tang via high-performance liquid chromatography and liquid chromatography-electrospray ionization-mass spectrometry

Yang, Hye Jin,Yim, Nam-Hui,Lee, Kwang Jin,Gu, Min Jung,Lee, Bohyoung,Hwang, Youn-Hwan,Ma, Jin Yeul Elsevier Science B.V., Amsterdam 2016 Integrative medicine research Vol.7 No.4

<P><B>Background</B></P><P>Yijin-tang (YJ) has been used traditionally for the treatment of cardiovascular conditions, nausea, vomiting, gastroduodenal ulcers, and chronic gastritis. In this study, a simple and sensitive high-performance liquid chromatography (HPLC) method was developed for the quantitation of nine bioactive compounds in YJ: homogentisic acid, liquiritin, naringin, hesperidin, neohesperidin, liquiritigenin, glycyrrhizin, 6-gingerol, and pachymic acid.</P><P><B>Methods</B></P><P>Chromatographic separation of the analytes was achieved on an RS Tech C<SUB>18</SUB> column (4.6 mm × 250 mm, 5 μm) using a mobile phase composed of water containing 0.1% (v/v) trifluoroacetic acid (TFA) and acetonitrile with a gradient elution at a flow rate of 1.0 mL/min.</P><P><B>Results</B></P><P>Calibration curves for all analytes showed good linearity (R<SUP>2</SUP> ≥ 0.9995). Lower limits of detection and lower limits of quantification were in the ranges of 0.03–0.17 μg/mL and 0.09–0.43 μg/mL, respectively. Relative standard deviations (RSDs; %) for intra- and interday assays were < 3%. The recovery of components ranged from 98.09% to 103.78%, with RSDs (%) values ranging from 0.10% to 2.59%.</P><P><B>Conclusion</B></P><P>This validated HPLC method was applied to qualitative and quantitative analyses of nine bioactive compounds in YJ and fermented YJ, and may be a useful tool for the quality control of YJ.</P>

Threading dislocation reduction in epitaxial GaN using V-groove patterned sapphire substrate with embedded silica nanospheres

Han, N.,Park, Y. J.,Han, M.,Ryu, B. D.,Ko, K. B.,Chandramohan, S.,Choi, C. J.,Cuong, T. V.,Hong, C. H. Elsevier Science B.V., Amsterdam. 2014 Materials letters Vol.123 No.-

dramatic reduction in threading dislocation density and stress-relaxation was simultaneously achieved in GaN epilayer using a silica nanosphere embedded structure on V-groove patterned sapphire substrate by metal-organic chemical vapor deposition. By depositing silica nanospheres at two different instances during a growth process, a two-step growth that included selective area growth and lateral overgrowth was initiated. This approach led to GaN template of high crystal quality, which was confirmed from x-ray diffraction rocking curve and micro-Raman measurements and further corroborated by transmission electron microscopy. GaN light-emitting diode fabricated by this strategy showed a significant enhancement in the light output power. (C) 2014 Elsevier B.V. All rights reserved.

Production of bioactive hydroxyflavones by using monooxygenase from Saccharothrix espanaensis

Lee, H.,Kim, B. G.,Ahn, J. H. Elsevier Science B.V., Amsterdam. 2014 Journal of biotechnology Vol.176 No.-

Biocatalysts are a valuable tool for the structural modification of fine chemicals. Flavonoids possess several biological activities, which are correlated to their antioxidant activity. The numbers of hydroxyl groups in flavonoids are critical for their antioxidant activity. Development of biocatalysts for hydroxylation of flavonoids is challenging because of the difficulty in expressing flavonoid hydroxylase in Escherichiacoli. In this study, a monooxygenase from Saccharothrix espanaensis (Sam5) was used for regioselective hydroxylation of flavonoids. We found that Sam5 hydroxylated isoflavones, flavanones, and flavones but did not produce any detectable hydroxylated product with flavonols. In addition, coexpression of P450 reductase with Sam5 in E. coli enhanced hydroxylation by approximately from 34 to 50%, depending on the flavonoid used. The production of two bioactive flavonoids, 8-hydroxyluteolin and T-hydroxydaidzein was optimized using this Sam5 system. Approximately 88 mg/L of 8-hydroxyluteolin and 75 mg/L of T-hydroxydaidzein were obtained. These results indicate that the Sam5 system could be used for the production of bioactive hydroxylated flavonoids. (C) 2014 Elsevier B.V. All rights reserved.

Influence of polar solvents on photovoltaic performance of Monascus red dye-sensitized solar cell

Lee, J. W.,Kim, T. Y.,Ko, H. S.,Han, S.,Lee, S. H.,Park, K. H. Elsevier Science B.V., Amsterdam. 2014 Spectrochimica acta. Part A, Molecular and biomole Vol.126 No.-

Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (J(sc)) of 1.23 mA/cm(2), a photovoltage (V-oc) of 0.75 V. and a fill factor of 0.72, corresponding to an energy conversion efficiency (eta) of 0.66%. (C) 2014 Elsevier B.V. All rights reserved.