• Title/Summary/Keyword: Activation factor

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Electoless Ni Plating on Alumina Powder to Application of MCFC Anode Material (MCFC anode 대체 전극 개발을 위한 분말 알루미나 상의 무전해 Ni 도금 연구)

  • Kim, Ki-Hyun;Cho, Kye-Hyun
    • Journal of the Korean institute of surface engineering
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    • v.40 no.3
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    • pp.131-137
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    • 2007
  • The typical MCFC (molten carbonate fuel cell) anode is made of Ni-10%Cr alloy. The work of this paper is focused concerning long life of anode because Ni-10% Cr anode is suffering from sintering and creep behavior during cell operation. Therefore, Ni-coated Alumina powder($20{\mu}m$) was developed by electroless nickel plating. Optimum condition of electroless nickel coation on $20{\mu}m$ alumina is as follows: pH 11.7, temperature $65{\sim}80^{\circ}C$, powder amount $100cm^2/l$. The deposition rate for Ni-electroless plating was as a function of temperature and activation energy was evaluated by Arrhenius Equation thereby activation energy calculated slope of experimental data as 117.6 kJ/mol, frequency factor(A) was $6.28{\times}10^{18}hr^{-1}$, respectively.

NF-${\kappa}B$ Activation by Compounds Found in Platycodon grandiflorum Extract

  • Hong, Sung-Won;Yong, Yeon-Joong;Kang, Kyung-Rai;Shin, Soon-Young;Lee, Young-Han;Lim, Yoong-Ho
    • Journal of Microbiology and Biotechnology
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    • v.19 no.6
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    • pp.556-559
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    • 2009
  • Compounds extracted from Platycodon grandiflorum were evaluated for an activation effect on nuclear factor-kappa B (NF-${\kappa}B$). In its active state, NF-${\kappa}B$ turns on the expression of genes related to cell proliferation or death. NF-${\kappa}B$ activators promote growth of neuron cells and can be used to control neurodegenerative diseases. The biological activity of P. grandiflorum extracts toward NF-${\kappa}B$ had not yet been studied. Although the biological activity of several compounds extracted from P. grandiflorum was evaluated, only three exhibited any significant activation effect on NF-${\kappa}B$.

Independent regulation of antigen processing and presentation on induction of antibody responses to various bacterial antigens in C3H/He mice

  • Kim, Hyung-Su;Jeong, Gajin
    • Journal of Microbiology
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    • v.33 no.4
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    • pp.355-362
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    • 1995
  • Induction of antibody production in C3H/He mice by bacterial infection is regulated through the processing exerted by antigen presenting cells. From the studies with Psudomonas aeruginosa, Salmonella typhimurium, and Micrococcus luteu, lipopolysaccharides (LPS) in Gram negative bacteria, which are known to be T-cell independent B cell mitogen, seem to be the major factor stimulating immune responses via activation of macrophages. Activation of macrophage, however, does not seem to correlate with antibody production. M. luteus was easily eliminatd by activated macrophages, while the processed antigens were immediately releasedd into culture medium before presentation. Nevertheless, antigens from Gram positive bacteria, Staphylococcus aureus and Bacillus subtilis, were very very active in chemotaxis and activation of periotoneal macrophages as well as in antien presnetation, while the very nature of the antigens is not yet clearly understood.

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A Fundamental Study on the Effect of Activation Function in Predicting Carbonation Progress Using Deep Learning Algorithm (딥러닝 알고리즘 기반 탄산화 진행 예측에서 활성화 함수 적용에 관한 기초적 연구)

  • Jung, Do-Hyun;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.11a
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    • pp.60-61
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    • 2019
  • Concrete carbonation is one of the factors that reduce the durability of concrete. In modern times, due to industrialization, the carbon dioxide concentration in the atmosphere is increasing, and the impact of carbonation is increasing. So, it is important to understand the carbonation resistance according to the concrete compounding to secure the concrete durability life. In this study, we want to predict the concrete carbonation velocity coefficient, which is an indicator of the carbonation resistance of concrete, through the deep learning algorithm, and to find the activation function suitable for the prediction of carbonation rate coefficient as a process to determine the learning accuracy through the deep learning algorithm. In the scope of this study, using the ReLU function showed better accuracy than using other activation functions.

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Low-dose radiation activates Nrf1/2 through reactive species and the Ca2+/ERK1/2 signaling pathway in human skin fibroblast cells

  • Lee, Eun Kyeong;Kim, Jin-Ah;Park, Seong Joon;Kim, Jeung Ki;Heo, Kyu;Yang, Kwang Mo;Son, Tae Gen
    • BMB Reports
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    • v.46 no.5
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    • pp.258-263
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    • 2013
  • In the current study, we explored the effect of LDR on the activation of Nrfs transcription factor involved in cellular redox events. Experiments were carried out utilizing 0.05 and 0.5 Gy X-ray irradiated normal human skin fibroblast HS27 cells. The results showed LDR induced Nrf1 and Nrf2 activation and expression of antioxidant genes HO-1, Mn-SOD, and NQO1. In particular, 0.05 Gy-irradiation increased only Nrf1 activation, but 0.5 Gy induced both Nrf1 and Nrf2 activation. LDR-mediated Nrf1/2 activation was accompanied by reactive species (RS) generation and $Ca^{2+}$ flux. This effect was abolished in the presence of N-acetyl-cysteine and BAPTA- AM. Furthermore, Nrf1/2 activation by LDR was suppressed by PD98059, an inhibitor of ERK1/2. In conclusion, LDR induces Nrf1 and Nrf2 activation and expression of Nrf-regulated antioxidant defense genes through RS and $Ca^{2+}$/ERK1/2 pathways, suggesting new insights into the molecular mechanism underlying the beneficial role of LDR in HS27 cells.

The effect of Sagunja-tang on TNBS-induced Inflammatory Bowel Disease in Mouse (사군자탕(四君子湯)이 TNBS로 유발(誘發)된 생쥐의 염증성(炎症性) 장질환(腸疾患)에 미치는 영향(影響))

  • Hong, Sang-Sun;Ryu, Bong-Ha;Yoon, Seong-Woo;Kim, Jin-Sung
    • The Journal of Internal Korean Medicine
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    • v.31 no.4
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    • pp.731-751
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    • 2010
  • Objectives : The present study aimed to find out the effect of Sagunja-tang on the prevention and treatment of inflammatory bowel disease using mice with TNBS-induced inflammatory bowel disease. Methods : Mice with TNBS-induced inflammatory bowel disease were medicated with Sagunja-tang, and the weight changes, colon length, lipid peroxidation, and myeloperoxidase activity were observed. Levels of the inflammatory markers interleukin (IL)-$1{\beta}$ and cyclooxygenase-2 (COX-2), its transcription factor activation, phospho-NF-${\kappa}$B (pp65), in the colon by enzyme-linked immunosorbent assay and immunoblot analysis were also measured. Finally, the activation of fecal bacterial enzyme, ${\beta}$-glucuronidase and degradation activation of fecal glycosaminoglycan (GAG) and hyaluronic acid were observed. Results : We found that oral administration of Sagunja-tang inhibited TNBS-induced colon shortening and also inhibited myeloperoxidase activity in the colon of mice as well as IL-$1{\beta}$ and COX-2 expression. Sagunja-tang also inhibited TNBSinduced lipid peroxidation and pp65 activation in the colon of mice. In addition, Sagunja-tang inhibited ${\beta}$-glucuronidase activation and fecal hyaluronic acid degradation activation. Conclusions : It is supposed that Sagunja-tang has a potential therapeutic effect on inflammatory bowel disease through the inhibition of both NF-${\kappa}$B activation and lipid peroxidation, and the improvement of intestinal conditions.

Platelet-Activating Factor Enhances Experimental Pulmonary Metastasis of Murine Sarcoma Cells by Up-regulation of Matrix Metalloproteinases-9 Through NF-$\kappa$B-Dependent Pathway

  • Ko, Hyun-Mi;Back, Hae-Kyong
    • Biomedical Science Letters
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    • v.10 no.2
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    • pp.143-151
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    • 2004
  • Matrix metalloproteinases (MMPs) are capable of degrading extracellular matrix, a process that is necessary for angiogenesis, tumor invasion and metastasis. Platelet-activating factor (PAP) increases angiogenesis, tumor growth and metastasis through nuclear factor (NF)-$\kappa$B activation. Based on these facts, the involvement of MMPs in PAF-induced pulmonary metastasis was investigated in murine sarcoma cells, MMSV-BALB/3T3. Messenger RNA expression and enzymatic activity of MMP-9 were assessed by RT-PCR and zymography, and cell migration and metastasis were done for the detection of MMP-9 functional activity. PAP induced mRNA expression and enzymatic activity of MMP-9, and its effects were either inhibited by the PAP antagonist, WEB 2170 or by the NF-$\kappa$B inhibitor, parthenolide, or p65 antisense oligonucleotide in a dose-dependent manner. In addition, PAF induced promoter activity of MMP-9, which was inhibited by WEB 2170, phenanthroline, NAC, PDTC. These results indicate that PAF induces mRNA expression and enzymatic activity of MMP-9 in NF-$\kappa$B dependent manner. Cell migration assay showed that PAF induced MMSV-BALB/3T3 migration, and its effect was significantly inhibited by treatment with phenanthroline. PAF enhanced pulmonary metastasis of murine sarcoma cells, MMSV-BALB/3T3 was also reduced by phenanthroline. These results suggest that PAF-enhanced cell migration and pulmonary metastasis is mediated through the expression of MMP. In conclusion, It is suggested that PAF enhances pulmonary metastasis by inducing MMP-9 expression via the activation of NF-$\kappa$B.

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The distribution characteristics of trace elements of fine ambient particulate in Korea

  • Lim, Jong-Myoung;Lee, Jin-Hong;Kim, Ki-Hyun
    • Analytical Science and Technology
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    • v.18 no.3
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    • pp.241-249
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    • 2005
  • In this study, instrumental neutron activation analysis was used to measure the concentrations of about 30 trace elements in airborne particulate (PM2.5) samples at urban area of Daejeon city located in the southwestern region of Korea. An inspection of the measurement data indicates that the distribution patterns of trace elements could clearly distinguish the elements with their concentrations ranging over five orders of magnitude. The mean values for Lu and Dy were found to be the lowest at values of 0.01 and $0.04ng/m^3$, while those for K and Fe showed the highest value of 671 and $653ng/m^3$, respectively. The results of correlation analysis showed that PM2.5 concentrations can exhibit much more enhanced correlations with the elements of earth crustal components. The results of factor analysis further indicated that there are no more than six factors with statistical significance, which may exert dominant roles in regulating the elemental concentration levels in the study area. Enrichment factor analysis supports explicit interpretation of results found by this factor analysis.

An Empirical Study on the Marketing Strategy for the Activation of management of the start-up Small Business (창업 소상공인들의 경영활성화를 위한 마케팅전략에 관한 실증연구 -커피전문점을 중심으로-)

  • Jung, Doo-Sig
    • Journal of Digital Convergence
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    • v.17 no.11
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    • pp.105-115
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    • 2019
  • This study was intended to analyze the effect of emotional marketing on brand awareness and purchase intention in the coffee shop and investigates how SNS usage play moderating effect roles between motional marketing and purchase intention. The results of analysis are summarized as follows. First, emotional marketing has a positive effect on purchase intention(especially, taste factor and visual facto). Second, in the analysis of the effect of emotional marketing on brand awareness, the significant influence factors were the taste factor, tactile factor, visual factor and auditory factor. Third, as a result of analyzing the effect of brand awareness on purchase intention, it was found that brand awareness had a significant positive(+) effect on purchase intention. Fourth, it was analyzed that the moderating effect of SNS usage between emotional marketing and purchasing intention is to be positive(+) influence in the all detail factors. Therefore, In the start-up stages, it may be helpful to actively use emotional marketing and SNS usage for business activation.

The Comparison of Commercial Serum-Free Media for Hanwoo Satellite Cell Proliferation and the Role of Fibroblast Growth Factor 2

  • In-sun Yu;Jungseok Choi;Mina K. Kim;Min Jung Kim
    • Food Science of Animal Resources
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    • v.43 no.6
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    • pp.1017-1030
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    • 2023
  • Fetal bovine serum (FBS), which contains various nutrients, comprises 20% of the growth medium for cell-cultivated meat. However, ethical, cost, and scientific issues, necesitates identification of alternatives. In this study, we investigated commercially manufactured serum-free media capable of culturing Hanwoo satellite cells (HWSCs) to identify constituent proliferation enhancing factors. Six different serum-free media were selected, and the HWSC proliferation rates in these serum-free media were compared with that of control medium supplemented with 20% FBS. Among the six media, cell proliferation rates were higher only in StemFlexTM Medium (SF) and Mesenchymal Stem Cell Growth Medium DXF (MS) than in the control medium. SF and MS contain high fibroblast growth factor 2 (FGF2) concentrations, and we found upregulated FGF2 protein expression in cells cultured in SF or MS. Activation of the fibroblast growth factor receptor 1 (FGFR1)-mediated signaling pathway and stimulation of muscle satellite cell proliferation-related factors were confirmed by the presence of related biomarkers (FGFR1, FRS2, Raf1, ERK, p38, Pax7, and MyoD) as indicated by quantitative polymerase chain reaction, western blotting, and immunocytochemistry. Moreover, PD173074, an FGFR1 inhibitor suppressed cell proliferation in SF and MS and downregulated related biomarkers (FGFR1, FRS2, Raf1, and ERK). The promotion of cell proliferation in SF and MS was therefore attributed to FGF2, which indicates that FGFR1 activation in muscle satellite cells may be a target for improving the efficiency of cell-cultivated meat production.