• Title/Summary/Keyword: PC membrane

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Laser Based Temperature Measurement of Rotating Disk Using Thermocolor (서모컬러를 이용한 회전 디스크의 레이저 온도 측정)

  • Na, Wonhwi;Yoo, JaeChern
    • Journal of Sensor Science and Technology
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    • v.22 no.1
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    • pp.49-53
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    • 2013
  • In this paper, we proposed a laser-based non-contact temperature measuring method for high speed rotating polycarbonate (PC) disk using transparency change of thermocolor. The thermocolor has abilities to change color and transparency due to a change in temperature. The thermocolor is applied on one side of polyvinylidene fluoride (PVDF) membrane. The thermocolor applied membrane is attached to inside of reaction chamber in disk. An optical system consisted of a laser beam radiator and a laser photometer is installed. Laser is irradiated at the bottom side of disk and the transmitted laser beam is detected by the laser photometer at the opposite side of disk. During the disk is rotating, laser is irradiated and detected simultaneously. The laser photometer senses the transmitted laser power and generates voltage as output. The temperature of disk can be detected during the disk is rotating up to 3000 RPM.

Fast Fabrication of Nanoporous Anodic Alumina Membrane by Hard Anodization (하드애노디제이션에 의한 나노다공질 양극산화 알루미나 멤브레인의 제조)

  • Ha, Yoon-Cheol;Jeong, Dae-Yeong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.429-429
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    • 2009
  • Nanoporous anodic alumina membranes (NAAM) with high-density through-hole pores fabricated by hard anodization of aluminum in 0.3 M oxalic acid under the applied voltage of 40 (mild anodization), 80, 100, 120 and 140 V were investigated. The current-time responses monitored using a PC-controlled anodization cell and the corresponding pore structures attainable from field-enhanced scanning electron microscopy (FE-SEM) were analyzed in order to establish the optimum fabrication process. The nanoporous structure can be produced for all the voltage conditions, while the stabilized through-hole pore formation seems to occur at 40, 80 and 140 V. The growth rate under 140 V hard anodization was over 30 times higher than under 40 V mild anodization (1.5 um/hr).

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Induction of Apoptotic Cell Death by a Ceramide Analog in PC-3 Prostate Cancer Cells

  • Oh, Ji-Eun;So, Kwang-Sup;Lim, Se-Jin;Kim, Mie-Young
    • Archives of Pharmacal Research
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    • v.29 no.12
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    • pp.1140-1146
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    • 2006
  • Ceramide analogs are potential chemotherapeutic agents. We report that a ceramide analog induces apoptosis in human prostate cancer cells. The ceramide analog induced cell death through an apoptotic mechanism, which was demonstrated by DNA fragmentation, the cleavage of poly ADP ribose polymerase (PARP), and a loss of membrane asymmetry. Treating the cells with ceramide analog resulted in the release of various proapoptotic mitochondrial proteins including cytochrome c and Smac/DIBLO into the cytosol, and a decrease in the mitochondrial membrane potential. In addition, the ceramide analog decreased the phospho-Akt and phospho-Bad levels. The expression of the antiapoptotic Bcl-2 decreased slightly with increasing Bax to Bcl-2 ratio. These results suggest that the ceramide analog induces apoptosis by regulating multiple signaling pathways that involve the mitochondrial pathway.

Development of Monitoring System for Proton Exchange Membrane fuel Cell Driven Scooter (고분자 전해질 연료전지 스쿠터 모니터링 시스템 개발)

  • Kim, Dae-Hong;Kim, Jun-Young;Park, Kyu-Nam;Park, Kwon-Pil;Chung, Hoi-Bum;Song, Myung-Hyun
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.167-169
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    • 2008
  • A 1.2KW Proton Exchange Membrane Fuel Cell(PEMFC) stack(Nexa Power Module) is installed to motor driven general scooter. The 24V, 650W BLDC motor is used for actuator and 2nd battery(24V, 4Ah) is used for stable starting of this motor. The operating information of Nexa Power Nodule is transmitted by RS-232 serial communication to notebook PC, and that data is analysed and displayed by the LabVIEW monitoring system.

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Antiapoptotic Effect of Aurintricarboxylic Acid; Extracellular Action versus Inhibition of Cytosolic Protein Tyrosine Phosphatases

  • Lee, Dong-Yoon;Kim, Mee-Kyung;Kim, Mi-Jeong;Bhattarai, Bharatraj;Kafle, Bhooshan;Lee, Keun-Hyeung;Kang, Jae-Seung;Cho, Hyeong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.29 no.2
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    • pp.342-346
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    • 2008
  • Aurintricarboxylic acid (ATA) prevents apoptosis in a wide range of cell types, including PC12 cells. ATA is known to increase the phosphorylation level of IGF-1 receptor (IGF-1R) and downstream signaling proteins. ATA can translocate across the plasma membrane of PC12 cells and inhibit protein tyrosine phosphatases (PTPs) and, therefore, it is not clear whether ATA exerted its antiapoptotic effect through activation of IGF-1R or by inhibition of cytosolic PTPs. When PC12 cells, deprived of serum, were treated with Fab fragment of anti-IGF-1R antibody to prevent the binding of ATA to the extracellular domain of IGF-1R, ATA was found to penetrate into the cytosolic space of the cells. Under these conditions, the survival-promoting effects of ATA were abolished, and the increase of phosphorylation and characteristic cleavage of IGF-1R were not observed. These results indicate that the antiapoptotic effect of ATA in PC12 cells is due to the binding of ATA to the extracellular domain of IGF-1R and subsequent activation of the IGF-1R, not inhibition of cytosolic PTP(s).

Micro-Heatsink Fabricated by Electroless Plating (무전해 도금으로 제조한 마이크로 히트싱크)

  • An Hyun Jin;Son Won Il;Hong Joo Hee;Hong Jae-Min
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.2 s.31
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    • pp.11-16
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    • 2004
  • Electronic devices are getting smaller due to integration of electronic chip, and heat generated in electronic devices can cause loss of performance and/or reliability of the devices. In this research, metals such as gold, nickel and copper are plated onto a porous membrane by electroless plating method to make an efficient micro-heatsinks. Electroless plating includes sensitization and activation steps in pre-treatment steps. A polycarbonate(PC) membrane was sensitizied, activated and deposited in each metal solution for plating. Among manufactured microfibrils, heat transfer and radiation properties of Ni-microfibril with high surface area were more effective than those of $Au^-$ and Cu-microfibril.

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Polygonum cuspidatum Extract Induces Apoptosis in Human Uterine Cervical Carcinoma ME-180 Cells (호장근(虎杖根)이 자궁경부암세포(子宮經部癌細胞)의 성장억제(成長抑制) 및 세포고사(細胞枯死)에 미치는 영향)

  • Choi, Byun-Tak;Kim, Yeon-Hee;Lee, Dong-Nyung;Kim, Hyung-Jun
    • The Journal of Korean Obstetrics and Gynecology
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    • v.19 no.1
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    • pp.1-13
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    • 2006
  • Purpose : Polygonum cuspidatum extract is an oriental herb which has been used for uterine diseases. In this study, the effects of Polygonum cuspidatum extract were investigated on inducing growth inhibition and apoptosis of human uterine cervical carcinoma cells. Methods : Viability of Polygonum cuspidatum extract-induced ME-180 cells was measured by MTT assay. Apoptotic cells were visualized by EtBr/AcOr staining under fluorescent microscope. Nucleosomal DNA fragmentation was assayed by agarose gel electrophoresis. Cell cycle distribution and changes in mitochondrial membrane potential were observed by flow cytometry. Results : Polygonum cuspidatum extract induced ME-180 cell death in a dose- and time-dependent manner. In the cells treated with Pc, the population of cells at sub-G1 phase significantly increased, and the condensed nuclei, apoptotic bodies and nucleosome-sized DNA were detected. Moreover, reduction in mitochondrial membrane potential was detected. Conclusion : Polygonum cuspidatum extract inhibits the growth and proliferation of ME-180 cells by apoptotic induction and facilitates its activity initiated by depolarization of mitochondria.

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Identification and Characterization of Phytochrome-Regulated Phospholipase D in Oat Cells (Avena sativa L.)

  • Park, Cheon;Park, Moon-Hwan;Chae, Quae
    • BMB Reports
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    • v.29 no.6
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    • pp.535-539
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    • 1996
  • The activation of phospholipase D (PLD) catalyzes hydrolysis of phosphatidylcholine (PC) to phosphatidic acid (PA) and choline in plants as well as animals. To determine the presence of PLD in oat cells, we prepared inside-out plasma membrane and cytosolic fractions from oat tissues. PLD activities in both cytosol and plasma membrane were detected by ion chromatography method. The activity of PLD in plasma membrane was dependent upon $Ca^{2+}$ concentration and was heat stable. To investigate whether G-protein couples to PLD, the effects of $GTP{\gamma}S$ and $GDP{\beta}S$ on the PLD activity were measured. PLD activity was dramatically increased 300~400% in the presence of 50 ${\mu}M$ $GTP{\gamma}S$ but not in the presence of 50 ${\mu}M$ $GDP{\beta}S$. These results indicate that G-protein may be involved in regulation of PLD activity. To identify whether PLD is regulated by red light receptor, phytochrome, we irradiated red, far-red, or red/far-red/red light on oat protoplasts. PLD activity has increased 5-fold and 3-fold by treatment with red light and red/far-red/red light, respectively. In contrast, irradiation with far-red light had little or no effect on PLD activity. These results suggest that phytochrome regulates PLD activity through activation of G-protein in oat cells.

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Prion Protein Does Not Interfere with SNARE Complex Formation and Membrane Fusion

  • Yang, Yoo-Soo;Shin, Jae-Il;Shin, Jae-Yoon;Oh, Jung-Mi;Lee, Sang-Ho;Yang, Joo-Sung;Kweon, Dae-Hyuk
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.782-787
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    • 2009
  • In prion disease, spongiform neurodegeneration is preceded by earlier synaptic dysfunction. There is evidence that soluble N-ethylmaleimide sensitive factor attachment receptor (SNARE) complex formation is reduced in scrapie-infected in vivo models, which might explain this synaptic dysfunction because SNARE complex plays a crucial role in neuroexocytosis. In the present study, however, it is shown that prion protein (PrP) does not interfere with SNARE complex formation of 3 SNARE proteins: syntaxin 1a, SNAP-25, and synaptobrevin. Sodium dodecyl sulfate-resistant complex formation, SNAREdriven membrane fusion, and neuroexocytosis of PC12 cells were not altered by PrP. Thus, PrP does not alter synaptic function by directly interfering with SNARE complex formation.

A POSSIBLE MECHANISM OF POLYACETYLENE: MEMBRANE CYTOTOXICITY

  • Kim, Hyeyoung;Lee, You-Hni;Kim, Shin-Il
    • Toxicological Research
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    • v.4 no.2
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    • pp.95-105
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    • 1988
  • The effects of polyacetylenes on living membrances, rat erythrocyte and murine leukemic L1210 cell as well as artificial lipid bilayer were determined to investigate the cytotoxic mechanism of polyacetylenes against cancer cell lines. As results, panaxydol and panaxynol caused erythrocyte hemolysis dose-dependently while panaxytriol had no lysis. For liposomes composed of phosphatidyl choline (PC) and phosphatidic acid(PA), all three polyacetylenes supressed the osmotic behavior at the same degree.

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