• Clinical and Experimental Pediatrics
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• v.53 no.7
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• pp.735-740
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• 2010

Renal fibrosis, characterized by tubulointerstitial fibrosis and glomerulosclerosis, is the final manifestation of chronic kidney disease. Renal fibrosis is characterized by an excessive accumulation and deposition of extracellular matrix components. This pathologic result usually originates from both underlying complicated cellular activities such as epithelial-to-mesenchymal transition, fibroblast activation, monocyte/macrophage infiltration, and cellular apoptosis and the activation of signaling molecules such as transforming growth factor beta and angiotensin II. However, because the pathogenesis of renal fibrosis is extremely complicated and our knowledge regarding this condition is still limited, further studies are needed.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.57-61
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• 1982

For evaluating kinetic parameters of various reactions and materials a straight- forward method has been studied by the variable heating rate method in DSC analysis. Based on the linear relationship between the logarithm of the heating rate and reciprocal Peak temperature, this method allows calculation of activation energy and the Arrhenius frequency factor by only one observation of the peak temperature versus the heating rate. According to tile D function, D=-In P(x)/dx, to x(=$\frac{E}{RT}$) we can calculate reasonably accurate activation energy, tile Arrhenius factor and the rate constant, and predict half-life times of various materials from the kinetic calculation.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.20-27
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• 2012

Complex permittivity spectra of Allyl Chloride (AC), 2-Butanone (2-BU) and their binary mixtures over the entire range of concentration were obtained using the Time Domain Reflectometry (TDR) technique in microwave frequency range at various temperatures. Static dielectric constant and relaxation time are obtained from complex permittivity spectra. Density ($\rho$) and refractive index ($n_D$) are also measured. These parameters are used to determine excess dielectric constant, excess inverse relaxation time, excess molar volume, excess molar refraction, polarity, Bruggeman factor and thermodynamic parameters viz. enthalpy of activation and entropy of activation. The values of static dielectric constant and relaxation time increases while density and refractive index decreases with the percentage of 2-Butanone in Allyl Chloride increases. Excess parameters were fitted to a Redlich-Kister equation.

• Biomedical Science Letters
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• v.18 no.3
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• pp.181-192
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• 2012

Toll-like receptors (TLRs) induce innate immune responses that are essential for host defense against invading microbial pathogens. In general, TLRs have two major downstream signaling pathways; myeloid differential factor 88 (MyD88) and Toll/IL-1R domain-containing adaptor inducing IFN-${\beta}$ (TRIF) leading to the activation of NF-${\kappa}B$ and IRF3. Numerous studies demonstrated that certain phytochemicals possessing anti-inflammatory effects inhibit NF-${\kappa}B$ activation induced by pro-inflammatory stimuli including lipopolysaccharide and tumor necrosis factor-${\alpha}$ ($TNF{\alpha}$). However, the direct molecular targets for such anti-inflammatory phytochemicals are not fully identified. In this paper, we will discuss about the molecular targets of phytochemicals in TLRs signaling pathways. These results present a novel anti-inflammatory mechanism of phytochemicals in TLRs signaling.

• Toxicological Research
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• v.25 no.4
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• pp.159-173
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• 2009

Nuclear factor erythroid derived 2-related factor-2 (Nrf2) is a master transcription regulator of antioxidant and cytoprotective proteins that mediate cellular defense against oxidative and inflammatory stresses. Disruption of cellular stress response by Nrf2 deficiency causes enhanced susceptibility to infection and related inflammatory diseases as a consequence of exacerbated immune-mediated hypersensitivity and autoimmunity. The cellular defense capacity potentiated by Nrf2 activation appears to balance the population of $CD4^+$ and $CD8^+$ of lymph node cells for proper innate immune responses. Nrf2 can negatively regulate the activation of pro-inflammatory signaling molecules such as p38 MAPK, NF-${\kappa}B$, and AP-1. Nrf2 subsequently functions to inhibit the production of pro-inflammatory mediators including cytokines, chemokines, cell adhesion molecules, matrix metalloproteinases, COX-2 and iNOS. Although not clearly elucidated, the antioxidative function of genes targeted by Nrf2 may cooperatively regulate the innate immune response and also repress the expression of pro-inflammatory mediators.

• Journal of Navigation and Port Research
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• v.33 no.4
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• pp.263-270
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• 2009

Busan North port is facing crisis due to the opening of the New port. The North Port and NewPort are competing for a limited volume of cargoes and this competition is leading after all to price competition, lowering cargo work fee that may result in the failure of both This paper proposed the balanced development plans, which are the strategies of business tie-up and activation between the North Port and NewPort by introducing the strategy of "co-opetition" and the analysis for the success factor of co-opetition: to solve this operational problems on Busan port. It is found out that activation strategy is more successful co-opetition strategy than business tie-up strategy. The execution for the two co-opetition strategies will lead Busan Port to the balanced development as well as the enhanced competitiveness and will leap Busan port into global hub port as well.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.8
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• pp.856-867
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• 1990

In this paper, the convergence and the learning accuracy of the back-propagation (BP) method in neural network are investigated by 1) analyzing the reason for decelerating the convergence of BP method and examining the rapid deceleration of the convergence when the learning is executed on the part of sigmoid activation function with the very small first derivative and 2) proposing the modified logistic activation function by defining, the convergence factor based on the analysis. Learning on the output patterns of binary as well as analog forms are tested by the proposed method. In binary output patter, the test results show that the convergence is accelerated and the learning accuracy is improved, and the weights and thresholds are converged so that the stability of neural network can be enhanced. In analog output patter, the results show that with extensive initial transient phenomena the learning error is decreased according to the convergence factor, subsequently the learning accuracy is enhanced.

• Journal of the Korean Ceramic Society
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• v.29 no.1
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• pp.9-14
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• 1992

Some of non-isothermal analysis methods are applied to CaO-MgO-Al2O3-SiO2 glass system to find the kinetics parameters of crystallisation, activation energy, Avrami component and frequency factor. The results using the non-isothermal analysis were compared to that of microstructure experiment. Analysis of the result has enabled to some methods to be to recommend as being the most appropriate equation to use in a glass system. It was shown that in the thermal analysis using the non-isothermal method of Kissinger, Augis-Bennett, Bansal, and Marotta, the calculation of activation energy is not much different, while Avrami component and frequency factor are different from applied each methods.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.457-457
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• 2013

Current-voltage (I-V) measurements of crystalline silicon solar cells was conducted under dark conditions with the temperature range of 260 K~350 K. Using the calculation method, we extracted the crucial factors of ideality factor (n) and activation energy (Ea) to investigate the carrier conducting path in the space charge region (SCR) and the quasi-neutral region (QNR). Values of n were decreased with increasing temperature in both SCR and QNR. We also conformed that the value of Ea of SCR was larger than that of QNR about 0.4 eV. The temperature dependence of n indicates that the carrier conducting path is dominated by carrier recombination-generation in the SCR region than in the QNR region.

• BMB Reports
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• v.48 no.10
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• pp.589-594
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• 2015

The shadow enhancer of the short gastrulation (sog) gene directs its sequential expression in the neurogenic ectoderm and the ventral midline of the developing Drosophila embryo. Here, we characterize three unusual features of the shadow enhancer midline activity. First, the minimal regions for the two different enhancer activities exhibit high overlap within the shadow enhancer, meaning that one developmental enhancer possesses dual enhancer activities. Second, the midline enhancer activity relies on five Single-minded (Sim)-binding sites, two of which have not been found in any Sim target enhancers. Finally, two linked Dorsal (Dl)- and Zelda (Zld)-binding sites, critical for the neurogenic ectoderm enhancer activity, are also required for the midline enhancer activity. These results suggest that early activation by Dl and Zld may facilitate late activation via the noncanonical sites occupied by Sim. We discuss a model for Zld as a pioneer factor and speculate its role in midline enhancer activity.