• Title/Summary/Keyword: Competing interaction

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ELLIPTIC SYSTEMS INVOLVING COMPETING INTERACTIONS WITH NONLINEAR DIFFUSIONS II

  • Ahn, In-Kyung
    • Communications of the Korean Mathematical Society
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    • v.12 no.4
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    • pp.869-880
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    • 1997
  • In this paper, we give sufficient conditions of certain elliptic systems involving competing iteractions with nonlinear diffusion rates. The existence of positive solution depends on the sign of the first eigenvalue of operators of Schr$\ddot{o}$dinger type. More precisely, if the sign of such operators are either both positive or both negative, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

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ALTERNATIVE PROOF OF EXISTENCE THEOREM FOR CERTAIN COMPETITION MODELS

  • Ahn, Inkyung
    • Journal of the Chungcheong Mathematical Society
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    • v.13 no.1
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    • pp.119-130
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    • 2000
  • We give alternative proof of the existence theorem for certain elliptic systems describing competing interactions with nonlinear di usion. The existence of positive solution depends on the sign of the principal eigenvalue of suitable operators of Schr$\ddot{o}$dinger type. If the sign of such operators are both positive, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

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ELLIPTIC SYSTEMS INVOLVING COMPETING INTERACTIONS WITH NONLINEAR DIFFUSIONS

  • Ahn, In-Kyung
    • Bulletin of the Korean Mathematical Society
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    • v.32 no.1
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    • pp.123-132
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    • 1995
  • Our interest is to study the existence of positive solutions to the following elliptic system involving competing interaction $$ (1) { -\partial(x,u,\upsilon)\Delta u = uf(x,u,v) { - \psi(x,u,\upsilon)\Delta \upsilon = \upsilon g(x,u,\upsilon) { \frac{\partial n}{\partial u} + ku = 0 on \partial\Omega { \frac{\partial n}{\partial\upsilon} + \sigma\upsilon = 0 $$ in a bounded region $\Omega$ in $R^n$ with a smooth boundary, where the diffusion terms $\varphi, \psi$ are strictly positive nondecreasing function, and k, $\sigma$ are positive constants. Also we assume that the growth rates f, g are $C^1$ monotone functions. The variables u, $\upsilon$ may represent the population densities of the interacting species in problems from ecology, microbiology, immunology, etc.

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CHIP promotes the degradation of mutant SOD1 by reducing its interaction with VCP and S6/S6' subunits of 26S proteasome

  • Choi, Jin-Sun;Lee, Do-Hee
    • Animal cells and systems
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    • v.14 no.1
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    • pp.1-10
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    • 2010
  • Previously we showed that CHIP, a co-chaperone of Hsp70 and E3 ubiquitin ligase, can promote the degradation of mutant SOD1 linked to familial amyotrophic lateral sclerosis (fALS) via a mechanism not involving SOD1 ubiquitylation. Here we present evidence that CHIP functions in the interaction of mutant SOD1 with 26S proteasomes. Bag-1, a coupling factor between molecular chaperones and the proteasomes, formed a complex with SOD1 in an hsp70-dependent manner but had no direct effect on the degradation of mutant SOD1. Instead, Bag-1 stimulated interaction between CHIP and the proteasome-associated protein VCP (p97), which do not associate normally. Over-expressed CHIP interfered with the association between mutant SOD1 and VCP. Conversely, the binding of CHIP to mutant SOD1 was inhibited by VCP, implying that the chaperone complex and proteolytic machinery are competing for the common substrates. Finally we observed that mutant SOD1 strongly associated with the 19S complex of proteasomes and CHIP over-expression specifically reduced the interaction between S6/S6' ATPase subunits and mutant SOD1. These results suggest that CHIP, together with ubiquitin-binding proteins such as Bag-1 and VCP, promotes the degradation of mutant SOD1 by facilitating its translocation from ATPase subunits of 19S complex to the 20S core particle.

ZAS3 represses NFκB-dependent transcription by direct competition for DNA binding

  • Hong, Joung-Woo;Wu, Lai-Chu
    • BMB Reports
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    • v.43 no.12
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    • pp.807-812
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    • 2010
  • $NF{\kappa}B$ and ZAS3 are transcription factors that control important cellular processes including immunity, cell survival and apoptosis. Although both proteins bind the ${\kappa}B$-motif, they produce opposite physiological consequences; $NF{\kappa}B$ activates transcription, promotes cell growth and is often found to be constitutively expressed in cancer cells, while ZAS3 generally represses transcription, inhibits cell proliferation and is downregulated in some cancers. Here, we show that ZAS3 inhibits $NF{\kappa}B$-dependent transcription by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. Transient transfection studies show that N-terminal 645 amino acids is sufficient to repress transcription activated by $NF{\kappa}B$, and that the identical region also possesses intrinsic repression activity to inhibit basal transcription from a promoter. Finally, in vitro DNA-protein interaction analysis shows that ZAS3 is able to displace $NF{\kappa}B$ by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. It is conceivable that ZAS3 has therapeutic potential for controlling aberrant activation of $NF{\kappa}B$ in various diseases.

Enhanced removal of phosphate on modified ion exchanger with competing ion (음이온 교환수지를 이용한 인제거 향상)

  • Nam, Ju-Hee;Lee, Sang-Hyup;Choi, Jae-Woo;Hong, Seok-Won;An, Byungryul
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.1
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    • pp.121-128
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    • 2013
  • The concern for dissolved phosphate in water/wastewater has been increasing because of the risk for eutrophication. A variety of conventional and advanced technologies were applied to meet the enforced new regulation of phosphate around the world. However, there still remained a lot of challenge because most introduced/developed method, for example, biological and physic-chemical treatment is not easy to satisfy the new regulation of phosphate in water. In order to meet the new regulation, the application of ion exchanger has been tried which showed that the removal efficiency for phosphate was strongly determined by in the presence of the competing ion, especially sulfate. As results, a new class of ion exchanger governed by ligand exchange was developed and investigated to increase the selectivity for phosphate. The current study using organic/inorganic anion exchanger developed with Lewis acid-base interaction confirms the selectivity for phosphate over sulfate. According to isotherm test and column test, the value of the maximum phosphate uptake (Q) showed 64 mg/g as $po{_4}^{3-}$ and the breakthrough for phosphate occurs after 1000 min and completely finishes at 2500 min, respectively.

Development of Fashion Retailing Store Type Attractiveness (FaRSTA) -Indirect Estimates Approach with Multiple Scale Items- (패션리테일링 점포유형별 쇼핑유인력(FaRSTA) 모델 개발에 대한 연구 -다속성 간접평가법 활용-)

  • Park, Jin Je;Lee, Jin Hwa
    • Journal of the Korean Society of Clothing and Textiles
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    • v.37 no.1
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    • pp.76-89
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    • 2013
  • The exploration of the interaction effect among the components of attractiveness is impossible; therefore, this study uses an indirect estimates approach with multiple scale items that can measure the interaction effect among the components of attractiveness to solve the problem of direct estimates. Previous studies focused on intra-store type competition as their subjects; subsequently, this study dealt with intra-store type competition as well as inter-store type competition in the competing and selecting activities among fashion retailing stores with different business models (such as department stores, road brand stores, discount stores, outlets and internet shopping malls). This study suggests a generalized model for shopping attractiveness of stores and proposes a fashion retailing store type attractiveness (FaRSTA) model instead of a simple relative importance between store selection standards.

Influence of Interaction Effects of Emotional Labor and Burnout on the Turnover Intention of Nursery Workers Based on Competing Value Frameworks Model (경쟁가치모형에 근거한 보육교사의 감정노동과 소진의 상호작용효과가 이직의도에 미치는 영향)

  • Sihn, Young Il
    • Journal of the Korea Convergence Society
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    • v.9 no.6
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    • pp.251-259
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    • 2018
  • The purpose of this study is to investigate the moderating effect of burnout on the relationship between emotional labor and turnover intention of nursery teachers. For this study, 296 teachers in nursery centers were surveyed. The data were analyzed by moderated regression analysis using SPSS V22.0 program using mean centering method. The results of the study are as follows. First, expressive emotional labor affects turnover intention and internal emotional labor did not affect turnover intention. Second, the factors that have the greatest influence on turnover intention were identified as burnout. Third, the interaction effect between burnout and deep emotional labor showed a similar moderation effect on turnover intention. Based on these results, the policy and practical measures to alleviate the burnout of the nursery teachers were suggested, and the ways of managing turnover intention by utilizing the interaction effect of the teacher burnout and deep emotional labor were suggested.

Knowledge translation in internationalization of the firms (지식 전환을 통한 기업 국제화 전략 -현대자동차 사례를 중심으로-)

  • Choi, Soon-Gwon;Jung, Jinchul;Baek, Yoon-Jung
    • Knowledge Management Research
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    • v.3 no.2
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    • pp.71-84
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    • 2002
  • Global firms have to acquire various kinds of knowledge from worldwide markets and use it strategically in local markets. Especially, the ability to learn competitive advantage of an industry leader or competing firm is a critical factor in a firm's competitiveness. The concept of knowledge transfer has been used to explain these phenomena. However, with the broadening concept of knowledge and increasing importance of interaction between firms, the perspective of knowledge transfer has reached its limits. In this study we will conceptualize the new concept of 'knowledge translation', and analyze the globalization case of Hyundai Motor Co. to improve the validity and usefulness of this perspective. The results show that knowledge translation is a critical factor of success in a firm's globalization and efficient management of the knowledge translation process enhances a firm's global competitiveness.

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Ginsenoside Rg$_3$ inhibits NMDA receptors in rat cultured hippocampal neurons: possible involvement of a glycine-binding site

  • Rhim, Hye-Whon
    • Proceedings of the Ginseng society Conference
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    • 2004.12a
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    • pp.7-11
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    • 2004
  • We previously reported that ginseng inhibited NMDA receptors in cultured hippocampal neurons. Here, we further examined the detailed mechanism of ginseng-mediated inhibition using its main active ingredient, ginsenoside Rg$_3$. Co-application of ginsenoside Rg$_3$ with increasing concentrations of NMDA did not change the EC$_{50}$ of NMDA to the receptor, suggesting ginsenoside Rg$_3$ inhibits NMDA receptors without competing with the NMDA-binding site. Ginsenoside Rg$_3$-mediated inhibition also occurred in a distinctive manner from the well-characterized NMDA receptor open channel blocker, MK-801, However, ginsenoside Rg$_3$ produced its effect in a glycine concentration-dependent manner and shifted the glycine concentration-response curve to the right without changing the maximal response, suggesting the role of ginsenoside Rg$_3$ as a competitive NMDA receptor antagonist. We also demonstrated that ginsenoside Rg$_3$ significantly protected neurons against NMDA insults. Therefore, these results suggest that ginsenoside Rg$_3$ protects NMDA-induced neuronal death via a competitive interaction with the glycine-binding site of NMDA receptors in cultured hippocampal neurons.

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