• Title/Summary/Keyword: IscA

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A Study on the 3-Dimensional Simulation System using Industrial Source Complex Model (Industrial Source Complex Model을 이용한 3차원 모사에 관한 연구)

  • Lim Dong Yun;Kim Sung Bin;Ko Jae Wook
    • Journal of the Korean Institute of Gas
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    • v.4 no.2 s.10
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    • pp.15-19
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    • 2000
  • This study compared and analyzed existing research on dispersion models and selected the EPA's Industrial Source Complex(ISC) model as a model suitable for the domestic petrochemical industry for 3-dimensional simulation and developed a simulation system applying. 3-dimensional algorithm with this ISC dispersion model as a basis As a result of this study, the 3D dispersion model based on ISC can help estimate a exact accident damage zone, make a emergency plan and control a ignition source.

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Identification of Pseudomonas aeruginosa Genes Crucial for Hydrogen Peroxide Resistance

  • Choi, Young-Seok;Shin, Dong-Ho;Chung, In-Young;Kim, Seol-Hee;Heo, Yun-Jeong;Cho, You-Hee
    • Journal of Microbiology and Biotechnology
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    • v.17 no.8
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    • pp.1344-1352
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    • 2007
  • An opportunistic human pathogen, Pseudomonas aeruginosa, contains the major catalase KatA, which is required to cope with oxidative and osmotic stresses. As an attempt to uncover the $H_2O_2$-dependent regulatory mechanism delineating katA gene expression, four prototrophic $H_2O_2$-sensitive mutants were isolated from about 1,500 TnphoA mutant clones of P. aeruginosa strain PA14. Arbitrary PCR and direct cloning of the transposon insertion sites revealed that one insertion is located within the katA coding region and two are within the coding region of oxyR, which is responsible for transcriptional activation of several antioxidant enzyme genes in response to oxidative challenges. The fourth insertion was within PA3815 (IscR), which encodes a homolog of the Escherichia coli iron-sulfur assembly regulator, IscR. The levels of catalase and SOD activities were significantly reduced in the iscR mutant, but not in the oxyR mutant, during the normal planktonic culture conditions. These results suggest that both IscR and OxyR are required for the optimal resistance to $H_2O_2$, which involves the expression of multiple antioxidant enzymes including KatA.

The development of a meteorological data conversion program for air dispersion modeling (대기확산모델 운영을 위한 국내기상자료 변환프로그램개발)

  • 임문혁;정의석;홍현수;김진완;김선규;김선태
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.349-350
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    • 2003
  • ISCST 등의 대기확산모델은 모두 EPA에서 개발된 것으로 모델 운영에 사용되는 모든 데이터가 미국의 실정에 맞게 프로그램 되어 있다. 특히 ISC모델을 운영하기 위하여 필요로 하는 기상자료를 생성하는 MIXHTS와 PCRAMMET등은 미국 기상청이나 기타 기상관련 기관에서 발표하는 자료를 사용하도록 되어있다. 따라서 ISC를 운영하는데 있어 국내 기상자료를 해당하는 형태로 전환해야 하는 번거로움이 있으며 우리나라 기상청에서 발표하는 기상자료의 형태와 MIXHTS PCRAMMET에서 요구하는 기상자료형태를 모두 알고 있어야만 ISC를 운영하기 위한 올바른 기상자료를 만들 수 있었다. (중략)

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On the AR Coating Method of Al-MIS(p-Si) Solar Cel (Al-MIS(p-Si) 태양전지의 AR Coating 방법)

  • 엄경숙;백수현
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.21 no.6
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    • pp.64-69
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    • 1984
  • We found that the maximum efficiency of Al-MIS (p-Si) solar ceil was shown at 80$\AA$ thickness of Al-film which was deposited with slower velocity than 0.6$\AA$/sec. It was coated with ZnS and SiO for Anti-Reflecting. In single coating, ZnS and SiO film had maximum Isc at 570 and 690 A thickness, respectively. We confirmed that these results agreed well with the quarter coating condition; n1d1=λ/4. In double coating, we held the one layer with its optimum thickness in single coating and controlled the other layer. The maximum value of Isc in this case was almost the same with it in single coating but was maintained its value in so wide range of thickness. Keeping the relation; n1d1=n2d2 as another way, we made the total thickness of film thinner to 70-90% of the sum of each optimum thickness in single coating. In this case Isc was higher value than 20% of it in any other previous case and was retained so wide range of thickness.

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Helicobacter pylori Vacuolating Toxin Exhibits Polar Activity of $Cl^-$ Secretion and Secretory Response to Carbachol in T84 Cells

  • Jin, Nan-Ge;Jin, Yong-Ri;So, In-Suk;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.5
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    • pp.289-293
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    • 2004
  • To investigate whether VacA (vacuolating toxin) produced by Helicobacter pylori Korean stain 99 induces intestinal secretion, purified VacA was added to T84 cell monolayers mounted in Ussing chambers, and electrical parameters were monitored. Mucosal addition of low pH-pretreated VacA increased short circuit current (Isc). The effect was time- and dose-dependent and saturable. The time-to-peak Isc was concentration-dependent. Chloride channel inhibitors, niflumic acid or 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), inhibited VacA-stimulated Isc. Carbachol (CCh)-induced increase of Isc was prolonged by the addition of VacA to the mucosal side only. The effect was unaltered by the addition of niflumic acid. VacA did not show cytopathic effects. These studies indicate that VacA is a nonlethal toxin that acts in a polar manner on T84 monolayers to potentiate $Cl^-$ secretion and the response to CCh secretion without decrease in monolayer resistance. VacA may contribute to diarrhea diseases in human intestinal epithelial cells.

Impact of Information Sharing Regarding Customer Returns Ratio on Optimal Sales Strategy under E-commerce

  • Saito, Yuta;Kusukawa, Etsuko
    • Industrial Engineering and Management Systems
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    • v.14 no.2
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    • pp.111-121
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    • 2015
  • A correct information of customer returns ratio under e-commerce is not always shared between supply chain (SC) members. Also, it is important issue for SC members to handle the unsold products in a market. This paper discusses the impact of information sharing of customer returns ratio on an optimal sales strategy including resale of customer returns and buyback policy for a SC under e-commerce with a manufacturer and a retailer. A retailer sells a single product and resells the resalable customer returns in the same market. A manufacturer produces the products and buys back the unsold products as to their quality from the retailer. The integrated SC (ISC) determines the optimal product order quantity to maximize the expected profit of the whole SC. The decentralized SC (DSC) makes the optimal decisions for order quantity and the wholesale price of products to maximize the expected profit of each SC member. The effect of information sharing is discussed between SC members under ISC and DSC. The analysis numerically investigates how information sharing of the returns ratio affects the optimal decision and the expected profits under ISC and DSC. Besides, effect of SC coordination to encourage the shift to ISC is discussed.

Transition of Isc according to Natural Solar Spectrum on c-Si and a-Si PV Module (결정질과 비정질 PV모듈의 자연광 스펙트럼에 따른 Isc의 변화)

  • Kong, Ji-Hyun;Ji, Yang-Geun;Kang, Gi-Hwan;Yu, Gwon-Jong;Ahn, Hyung-Geun;Han, Deuk-Young
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.86-91
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    • 2009
  • In this paper, we analyze the Transition of Isc by natural solar spectrum of c-Si and a-Si PV module. Commonly, performance of photovoltaic (PV) module is estimated under the standard test condition (STC). That is, solar irradiance $1kW/m^2$, solar spectrum distribution: AM1 5G, module temperature $25^{\circ}C$ This means it rarely meets actual outdoor conditions. The solar spectrum always changes. So it is rare to fit the standard solar spectrum AM1 5G defined in ASTM G173-03 or IEC 60904-3. Thus spectral response of PV module is different depending on the material. so we estimated the variation of Isc at every minutes by comparing c-Si PV module with a-si PV module for outdoor conditions.

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Base Specificity for DNA Interstrand Cross-Linking Induced by Anticancer Agent Bizelesin

  • Lee, Chong-Soon;Myung, Pyung-Keun;Gibson, Neil W.
    • Archives of Pharmacal Research
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    • v.19 no.3
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    • pp.191-196
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    • 1996
  • Bizelesin is a promising novel anticancer agent which is known to alkylate N3 of adenine to induce DNA interstrand cross-links (ISC) with in $5^I-TAATTA\; and\; 5^I-TAAAAAA$. We have investigated the base specificity for DNA ISC induced by bizelesin using oligomers containing the cross-linkable sequence $5^I-TAATTA\; and\; 5^I-TAAAAAA$. in which "N" was either A, C, G, or T. An analysis of denaturing polyacrylamide gel showed that bizelesin is able to induce DNA ISC in the duplex oligomer containing sequences $5^I-TAATTA\; and\; 5^I-TAAAAAA$. The formation of interstrand crosslinking did not occur in the sequences $5^I-TAATTA\; and\; 5^I-TAAAAAA$. DNA strand cleavage assay to determine the cross-linking site within $5^I-TAATTA$sequence showed that bizelesin alkylates guanine. These results demonstrate that bizelesin is able to induce DNA ISC at guanine but not at cytosine or thymine. In addition, guanine adducts have been found to be susceptible to DNA strand cleavage by exposure to hot piperidine. The extent of DNA strand cleavage, however, was not 100% efficient in either neutral pH buffer or hot piperidine.

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Effect of $H_2O_2$ on Alveolar Epithelial Barrier Properties (폐상피세포 장벽에 대한 $H_2O_2$의 영향)

  • Suh, Duk-Joon;Cho, Se-Heon;Kang, Chang-Woon
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.3
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    • pp.236-249
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    • 1993
  • Background: Among the injurious agents to which the lung airspaces are constantly exposed are reactive species of oxygen. It has been widely believed that reactive oxygen species may be implicated in the etiology of lung injuries. In order to elucidated how this oxidant causes lung cell injury, we investigated the effects of exogenous $H_2O_2$ on alveolar epithelial barrier characteristics. Methods: Rat type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with HEPES-buffered Ringer solution. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against $H_2O_2$ injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ, an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results: These monolayers have a high transepithelial resistance (>2000 ohm-$cm^2$) and actively transport $Na^+$ from apical fluid. $H_2O_2$(0-100 mM) was then delivered to either apical or basolateral fluid. Resulting indicated that $H_2O_2$ decreased Isc and R gradually in dose-dependent manner. The effective concentration of apical $H_2O_2$ at which Isc (or R) was decreased by 50% at one hour ($ED_{50}$) was about 4 mM. However, basolateral $H_2O_2$ exposure led to $ED_{50}$ for Isc (and R) of about 0.04 mM. Inhibition of cellular catalase yielded $ED_{50}$ for Isc (and R) of about 0.4 mM when $H_2O_2$ was given apically, while $ED_{50}$ for basolateral exposure to $H_2O_2$ did not change in the presence of ATAZ. The rate of $H_2O_2$ consumption in apical and basolateral bathing fluids was the same, while cellualr catalase activity rose gradually with time in culture. Conclusion: Our data suggest that basolateral $H_2O_2$ may affect directly membrane component (e.g., $Na^+,\;K^+$-ATPase) located on the basolateral cell surface. Apical $H_2O_2$, on the other hand, may be largely degraded by catalase as it passes through the cells before reaching these membrane components. We conclude that alveolar epithelial barrier integrity as measured by Isc and R are compromised by $H_2O_2$ being relatively sensitive to basolateral (and insensitive to apical) $H_2O_2$.

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A Study on the Electrification Mechanism in UHV Transformer by Couette Flow (Couette 흐름현상을 이용한 초고압변압기의 유동대전 기구 연구)

  • 곽희로;정용기;권동진
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.9 no.4
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    • pp.93-102
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    • 1995
  • The purpose of this paper is to analyze the streaming electrification mechanism (SEM) generated in UHV transformer. This experiment used Couette Charger and interpreted the mechanism hydromechanically and electromagnetically. This work estimated the turbulent core density ($\rho$o) by measuring the short circuit current (isc) and the open circuit voltage (νoc) generated in Couette Charger and also studied the changes of the short circuit (isc), the open circuit voltage (νoc), the turbulent core density ($\rho$o) and the conductivity ($\sigma$) with adding BTA to restrain streaming electrification. as a result adding BTA increased the conductivity of oil and decreased the turbulent core density($\rho$o).

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