• Title/Summary/Keyword: J-factor

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Hormonal Regulation of Insulin-Like Growth Factor Binding Protein Secretion by a Bovine Mammary Epithelial Cell Line

  • Kim, W.Y.;Chow, J.C.;Hanigan, M.D.;Calvert, C.C.;Ha, J.K.;Baldwin, R.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.2
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    • pp.233-239
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    • 1997
  • A mammary epithelial cell line (MAC-T) established as a model for lactation was utilized to identify and characterize effects of various hormones upon insulin-like growth factor binding protein secretion. Ligand and immunoblot analyses of conditioned media indicated that insulin-like growth factor binding protein-2 was secreted by MAC-T cells. Insulin-like growth factor-I stimulated insulin-like growth factor binding protein-2 secretion in a dose-dependent manner, but prolactin and bovine somatotropin did not alter insulin-like growth factor binding protein-2 secretion. Insulin increased and cortisol decreased insulin-like growth factor binding protein-2 secretion. Effects of insulin-like growth factor-I on insulin-like growth factor binding protein-2 secretion support previous studies using primary cultures of bovine mammary cells and bovine fibroblasts. Effects of cortisol and insulin on insulin-like growth factor binding protein-2 secretion may be explained by changes in protein synthesis. In addition, supraphysiological doses of insulin can cross-react with the insulin-like growth factor-I receptor and stimulate insulin-like growth factor binding protein-2 secretion. MAC-T cells provide a model system to study mechanisms that regulate local insulin-like growth factor-I bioactivity.

A Study on Characteristics of Pollutants from LNG Facilities (천연가스 사용설비 오염물질 배출특성 연구)

  • Lee, J.S.;Lee, H.C.;You, H.S.;Han, J.O.
    • 한국연소학회:학술대회논문집
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    • 2004.06a
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    • pp.223-226
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    • 2004
  • The thesis examined the charactcri:stlC of pollutants exhausted from LNG facilities. So, combustion gas and concentration of greenhouse gas exhausted from gas boiler for home use, furnace facilities, electric power facilities, boiler for industrial use and boiler for heating fueled LNG is measured. And the exhaust factor of pollutants is produced by classify of pollutants in detail. And this exhaust factor is compared and investigated with data of a foreign nations.

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Transcription factor NF-kB as a potential biomarker of oxidative stress to evaluate antioxidant effects

  • Berg, Robin van den;Sierksma, Aafje;Hendriks, Henk F.J.;Vaes, Wouter H.J.
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.05a
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    • pp.25-26
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    • 2003
  • There is increasing interest in the involvement of transcription factors, such as of the transcription factor NF-kB (nuclear factor-kB), in the pathogenesis of various diseases. The involvement ofNF-kB is especially of interest as it is activated by oxidative stress and its activation can be modulated by antioxidant compounds. (omitted)

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An Experimental Study on Air-Side Performance of Fin-and-Tube Heat Exchangers Having Compound Enhanced Fins (복합 전열 촉진 핀이 적용된 핀-관 열교환기의 성능에 대한 실험적 연구)

  • Kim, Nae-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.7
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    • pp.4364-4374
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    • 2015
  • In this study, heat transfer and friction characteristics of compound enhanced fin-and-tube heat exchangers were experimentally investigated. Louver-finned heat exchangers were also tested for comparison purpose. The effect of fin pitch on j and f factor was negligible. The j factor decreased as number of tube row increased. However, f factor was independent of number of tube row. Louver fin samples yielded higher j and f factors than compound enhanced fin samples. For one row, j and f factors of louver fin were 23% and 27% higher than those of compound enhanced fin. For two row, those were 11% and 8%, and for three row, those were 10% and 9%. However, heat transfer capacities at the same pressure drop of the compound enhanced fins were 6.4% for one row, 11.1% for two row and 13.6% for three row larger than those of louver fins, Existing louver fin correlation overpredicted the present j factors and underpredicted the present f factors.

A numerical study on heat transfer and pressure drop of plate heat exchanger using at seawater air conditioning with the variation of channel spaces (채널 간격 변화에 따른 해수냉난방용 판형 열교환기의 열전달과 압력강하에 대한 수치해석적 연구)

  • Kim, Hyeon-Ju;Lee, Ho-Saeng;Yoon, Jung-In;Son, Chang-Hyo;Jung, Young-Kwon
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.6
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    • pp.704-709
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    • 2014
  • Plate heat exchanger is being applied in the field of marine plants and chemical industry, such as OTEC and SWAC equipment. The study aims to interpret the heat transfer and pressure drop characteristics of plate heat exchangers to determine the geometric design parameters such as the channel space. In this study, heat transfer performance was numerically studied with respect to the variation of channel spaces. The results from numerical analysis indicated that the j factor was linearly decreased with the flowrate of seawater over every cases. As the flowrate of water increased with respect to channel spaces, the j factor decreased linearly. And the f factor decreased linearly with the increase of flowrate. When the channel space is 2.8~3.2 mm and 3.2~3.2 mm, respectively, the area goodness factor of plate heat exchanger showed the highest performance.

An Estimation of Constraint Factor on the ${\delta}_t$ Relationship (J-적분과 균열선단개구변위에 관한 구속계수 m의 평가)

  • 장석기
    • Journal of Advanced Marine Engineering and Technology
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    • v.24 no.6
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    • pp.24-33
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    • 2000
  • This paper investigates the relationship between J-integral and crack tip opening displacement, ${\delta}_t$ using Gordens results of numerical analysis. Estimation were carried out for several strength levels such as ultimate, flow, yield, ultimate-flow, flow-yield stress to determine the influence of strain hardening and the ratio of crack length to width on the $J-{\delta}_t$ relationship. It was found that for SE(B) specimens, the $J-{\delta}_t$ relationship can be applied to relate J to ${\delta}_t$ as follows $J=m_j{\times}{\sigma}_i{\times}{\delta}_t$ where $m_j=1.27773+0.8307({\alpha}/W)$, ${\sigma}_i:{\sigma}_U$, ${\sigma}_{U-F}={\frac{1}{2}} ({\sigma}_U+{\sigma}_F$), ${\sigma}_F$, ${\sigma}_F}$ $Y=({\sigma}_F+{\sigma}_Y)$, ${\sigma}_Y$

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Development of discharge lamp ballast for wave improvement (파형개선을 위한 방전등 안정기 개발)

  • Lee, O.K.;Song, D.S.;Kim, T.W.;Lee, J.T.;Song, H.S.;Kim, J.G.
    • Proceedings of the KIEE Conference
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    • 2000.07e
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    • pp.85-88
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    • 2000
  • This paper was development a discharge lamp ballast in order to wave improvement of high power factor and high efficiency. The discharge lamp ballast consists of a power factor correction circuit and a correction circuit on switching frequency of inverter. Instead of passive power factor circuit, active power factor circuit is adopted. Because it has the advantage of size, weight, total harmonic distortion, out DC voltage regulation, and power factor. The power factor circuit with MG34262 is controlled by variable frequency discontinuous mode. Results experiments, discharge lamp ballast is showed to have excellent for the proposed electronic ballast's operation and characteristics.

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