• Title/Summary/Keyword: Research Park

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Factors Affecting in Vitro Activity of LB20304, a New Flu-oroquinolone

  • Paek, Kyoung-Sook;Ahn, Mi-Jeong;Kim, Mu-Yong;Kim, In-Chull;Kwak, Jin-Hwan
    • Archives of Pharmacal Research
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    • v.19 no.2
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    • pp.143-147
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    • 1996
  • LB20304 is a novel fluoroquinolone that exhibits a potent broad spectrum antibacterial activity against both gram-positve and gram-negative bacteria. The MICs (Minimal Inhibitory Concentration) of LB20304 were determined against both gram-positve and gram-negative bacteria under various conditions including several media, pHs, and inoculum concentrations. The in vitro activity of LB20304 was not significantly affected by the changes in testing conditions such as components of media and inoculum concentrations, but it was slightly reduced by acid condition. The MICs and MBCs (Minimal Bactericidal Concentration) of LB20304 against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were hardly affected by the presence of 50 % human serum, mouse serum, guinea pig serum or horse serum, and the MBCs were equal to or at most four-times higher than the MiCs. The activities of LB20304 were decreased by the presence of high concentraion of $Mg^{++}$ or human urine (pH, 5.5) in the test media. The frequencies of mutants resistant to LB20304 were similar to or lower than those found in ciprofloxacin and sparfloxacin.

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Study on the Values for Urban Green Space in terms of University Students -The Case of Talsong Park in Taegu- (대학생집단의 도시 공원녹지에 대한 의식에 관한 연구 -대구시 달성공원을 중심으로-)

  • 김수봉;김정배
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.883-888
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    • 1998
  • The aim of this paper is to suggest basic guidelines for the urban park development policy in Taegu. This research is mainly based on university students' essay on <private inquiry of urban park in Taegu>. Talsong Park, the most popular site for the students' essay, was selected for the purpose of the study. The research focused on the general images of the park, negative images of the park and aspirations and demands for the park in relation with Talsong Park redevelopment policy. The research of this result suggested that the renovation of Talsong Park from zoo-oriented park to the historic & cultural park status. The other main suggestion was consideration of public participation from the planning stage for the betterment of park management. In addition, the importance of environmental education for the local people was stressed in order to enhance public awareness of environment for the solution of our common environmental problems in relation with Local Agenda 21.

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Identification of Ceftiofur Oxidation Products by High-Performance Liquid Chromatography/Electrospray Ionization/Tandem Mass Spectrometry

  • Lim, Young-Hee;Park, Deok-Hie;Youn, Yeu-Young;Kim, Kyung-Hoon;Cho, Hye-Sung
    • Mass Spectrometry Letters
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    • v.2 no.1
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    • pp.16-19
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    • 2011
  • Oxidation products of ceftiofur were formed in hydrogen peroxide solution. The structures of the ceftiofur oxidation products were characterized by high-performance liquid chromatography/electrospray ionization/tandem mass spectrometry (HPLC/ESI/MS/MS). The products were identified as compounds oxidized at the sulfur of a cephem ring. For further analysis, experiments were performed using $O^{18}$-labeled hydrogen peroxide. In addition, density-functional calculations were carried out for six possible oxidation products to support the experimental results.

Bactericidal activities of LB20304, a new fluoroquinolone

  • Paek, Kyoung-Sook;Kim, Mu-Yong;Kim, In-Chull;Kwak, Jin-Hwan
    • Archives of Pharmacal Research
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    • v.19 no.4
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    • pp.317-320
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    • 1996
  • The time-kill curves of LB20304, a novel fluoroquinolone that has potent antibacterial activity against gram-positve and gram-negative bacteria, were calculated at the concentrations of 1/4-, 1/2-, 1-, 2- and 4-times the MIC against Staphylococcus aureus 77, Escherichia coli 3739E, Pseudomonas aeruginosa 1912E. The bactericidal activity of LB20304 for these strains was very rapid and comparable to that of ciprofloxacin. LB20304 produced a decrease in the $log_10$ CFU per milliliter of${\geq}$3 within 2 h at 4-times the MIC for all strains and consitently prevented regrowth of bacteria after 24 h of incubation. The MBCs (Minimal Bactericidal Concentration) of LB20304 against test organisms were equal to or at most four-times higher than the MICs.

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A Novel Separator Membrane for Safer Lithium-ion Rechargeable Batteries

  • Lee, Sang-Young;Kim, Seok-Koo;Hong, Jang-Hyuck;Shin, Byeong-Jin;Park, Jong-Hyuck;Sohn, Joon-Yong;Jang, Hyun-Min;Ahn, Soon-Ho
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.69-70
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    • 2006
  • In lithium-ion batteries, separator membrane's, main role is to physically isolate a cathode and an anode while maintaining rapid transport of ionic charge carriers during the passage of electric current. As far as battery safety is concerned, the electrical isolation of electrodes is most crucial since unexpected short-circuits across the membrane induces hot spots where thermal runaway may break out. Internal short-circuits are generally believed to occur by protrusions on the electrode surface either by unavoidable deposits of metallic impurities or by dendritic lithium growth during battery operation. Another cause is shrinkage of the separator membrane when exposed to heat. If separator membrane can be engineered to prevent the internal short-circuit, it will not be difficult to improve lithium-ion batteries' safety. Commonly the separators employed in lithium-ion batteries are made of polyethylene (PE) and/or polypropylene (PP). These materials have terrible limitations in preventing the fore-mentioned internal short-circuit between electrodes due to their poor dimensional stability and mechanical strength. In this study we have developed a novel separator membrane that possesses very high thermal and mechanical stability. The cells employing this separator provided noticeable safety improvement in the various abuse tests.

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