• 제목/요약/키워드: Flow-through Cell

검색결과 644건 처리시간 0.029초

검사체적 유한요소법을 이용한 다축 브레이드 프리폼의 투과율 계수 예측 (Prediction of Permeability for Multi-axial Braided Preform by Using CVFEM)

  • Y. S. Song;K. Chung;T. J. Kang;J. R. Youn
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
    • /
    • pp.68-70
    • /
    • 2002
  • Prediction of 3-D permeability tensor for multi-axial preform is critical to model and design the manufacturing process of composites by considering resin flow through the multi-axial fiber structure. In this study, the in-plane and transverse permeabilities for braided preform are predicted numerically. The flow analyses are calculated by using 3-D CVFEM(control volume finite element method) for macro-unit cells. To avoid checker-board pressure field and improve the efficiency of numerical computation, a new interpolation function for velocity is proposed on the basis of analytic solutions. Permeability of a braided preform is measured through unidirectional flow experiment and compared with the permeability calculated numerically. Unlike other studies, the current study is based on more realistic unit cell and prediction of permeability is improved.

  • PDF

Cell Transmission 이론에 근거한 시스템최적 신호시간산정 (Development of A System Optimum Traffic Control Strategy with Cell Transmission Model)

  • 이광훈;신성일
    • 대한교통학회지
    • /
    • 제20권5호
    • /
    • pp.193-206
    • /
    • 2002
  • 신호교차로로 구성된 네트워크의 시스템최적 신호시간산정을 위해 Cell Transmission 이론을 교통류 모형으로 활용한 신호최적화 모형을 제안한다. Cell Transmission 모형은 기존에 소개된 신호최적화 모형과는 달리 충격파, 대기행렬의 길이, 그리고 하류부 교차로 대기행렬의 역류(Spillback)과 같은 과포화 현상을 표현하는데 적절한 이론적이고 실제적인 배경을 지원한다. 모형에서 기점을 출발한 수요차량은 종점에 도착할 때까지 경로선택을 통해서, 그리고 신호시스템은 이러한 수요의 움직임 고려하여 신호시간요소의 최적화를 통한 네트워크의 비용을 최소화하기 위해 서로 협력한다는 의미에서 제안된 모형은 시스템 최적화를 의미한다. 모형은 혼합정수계획법으로 정식화되며 최적신호전략과 고정신호전략간의 실험계획을 통해 구축된 모형을 비교·평가한다.

혈부축어탕(血府逐瘀湯) 자궁근종세포의 증식억제와 Apoptosis 관련 유전자 발현에 미치는 영향 (Effect of Hyulbuchukeotang on the Inhibition of Proliferation of Uterine leiomyoma cells and Cell apoptosis)

  • 문나영;백승희;김동철
    • 대한한방부인과학회지
    • /
    • 제19권2호
    • /
    • pp.186-198
    • /
    • 2006
  • Purpose : The purpose of this study is to demonstrate the direct inhibitory effect of Hyulbuchukeotang on the proliferation of uterine leiomyoma cells through an experiment treating uterine leiomyoma cells cultivated by explantation with indicated concentrations of Hyulbuchukeotang and to research the gene expression related to cell cycle ill order to discover the connection with apoptosis and its mechanism by analyzing cell cycle. Methods : After primary culture of uterine leiomyoma cells, the cultivated uterine leiomyoma cells were treated with indicated concentrations of Hyulbuchukeotang for 24 hours. The inhibitory effect on the cell proliferation was determined by the cell count assay. The value of a cell count assay represent the percentage of cells in a phase of the cell cycle compared with total cells. In addition, a link between Hyulbuchukeotang and apoptosis was examined through flow cytometric analysis by FACS and DNA fragmentation analysis. Finally, the degree of gene expression related to cell cycle was evaluated by Western blot analysis. Results : The inhibitory effect of Hyulbuchukeotang increase of uterine leiomyoma cells treated with indicated concentrations of Hyulbuchkeotang increases. The result of gene expression related to G1 phase after treating with 100, 250, 500, 1,000 ${\mu}g/ml$ concentrations of Hyulbuchukeotang. on uterine leiomyoma cells is that the gene expression of p27 was increased but that of p53 an p21 remained unchanged and the gene of pRB, pro-caspase 3 was decreased. Conclusion Through the mentioned experiments, it is demonstrated that Hyulbuchkeotang is effective in inhibiting Proliferation of uterine leiomyoma cells by extending cell cycle G1. However it is not considered that the inhibitory effect results from the aptoposis.

  • PDF

FAM46B inhibits cell proliferation and cell cycle progression in prostate cancer through ubiquitination of β-catenin

  • Liang, Tao;Ye, Xuxiao;Liu, Yuanyuan;Qiu, Xinkai;Li, Zuowei;Tian, Binqiang;Yan, Dongliang
    • Experimental and Molecular Medicine
    • /
    • 제50권12호
    • /
    • pp.8.1-8.12
    • /
    • 2018
  • FAM46B is a member of the family with sequence similarity 46. Little is known about the expression and functional role (s) of FAM46B in prostate cancer (PC). In this study, the expression of FAM46B expression in The Cancer Genome Atlas, GSE55945, and an independent hospital database was measured by bioinformatics and real-time PCR analysis. After PC cells were transfected with siRNA or a recombinant vector in the absence or presence of a ${\beta}$-catenin signaling inhibitor (XAV-939), the expression levels of FAM46B, C-myc, Cyclin D1, and ${\beta}$-catenin were measured by western blot and realtime PCR. Cell cycle progression and cell proliferation were measured by flow cytometry and the CCK-8 assay. The effects of FAM46B on tumor growth and protein expression in nude mice with PC tumor xenografts were also measured. Our results showed that FAM46B was downregulated but that ${\beta}$-catenin was upregulated in patients with PC. FAM46B silencing promoted cell proliferation and cell cycle progression in PC, which were abrogated by XAV-939. Moreover, FAM46B overexpression inhibited PC cell cycle progression and cell proliferation in vitro and tumor growth in vivo. FAM46B silencing promoted ${\beta}$-catenin protein expression through the inhibition of ${\beta}$-catenin ubiquitination. Our data clearly show that FAM46B inhibits cell proliferation and cell cycle progression in PC through ubiquitination of ${\beta}$-catenin.

평판형 연료전지 스택의 제조를 위한 매니폴드 형상별 압력분포 시뮬레이션 (Pressure Distribution Simulation on Geometrical Manifolds Structure for Fabrication of a Planar-type Fuel-Cell Stack)

  • 박세준;최용성;이경섭
    • 전기학회논문지P
    • /
    • 제58권4호
    • /
    • pp.609-614
    • /
    • 2009
  • A fuel-cell power system among various alternative power sources has many advantages such as comparatively independable circumstances, high-efficient, and heat-recyclable, thus it is now able to be up to hundreds MWh-scaled through improving feasibility and longevity of it. During the last few decades, numerous research results has been investigated to expand interest in fuel-cell technology. This study presents pressure distribution on the geometrical manifold structures, which are U-type and Z-type, of a planar-type fuel-cell stack by simulated with computational fluid dynamics(CFD). Then, electrical performance of a 200W fuel-cell stack, which is U-type, was diagnosed after pre-conditioning operation. The stack has electrical characteristics ; 22V, 10A, 220W, and current density $200mA/cm^2$.

용해기체 분석용 기체감응막 이온선택성 전극 (제 4 보) 관형 PVC막 pH전극을 이용한 황화이온의 연속 · 자동화 정량 (Gas-Sensing Membrane Electrodes for the Determination of Dissolved Gases (Ⅳ). Continuous-Automated Determination of Sulfide Ion Using Tubular PVC Membrane Type pH Electrode)

  • 이흥락;배준웅;오상협
    • 대한화학회지
    • /
    • 제36권5호
    • /
    • pp.638-643
    • /
    • 1992
  • 황화이온검출기로서 2가지 형태의 연속 flow-through 전극계의 분석적 감응성질을 조사하고, 최적조건에서 그들의 감응특성을 직접 비교하였다. 두 검출계에 있어서 측정한 봉우리전위를 황화이온농도의 대수값과 관련지웠으며, 적어도 시간당 20개의 시료를 정량할 수 있었다. pH전극법에서는 투석기를 지나 흘러가는 recipient stream의 pH를 측정하였다. 장치는 연속흐름형의 기체투석기가 관형 polymer 막전극과 연결되도록 설계되어 있다. 이 방법의 최적실험조건은 recipient $5.0 {\times} 10^{-5} M NaOH + 5.0 {\times} 10^{-3} M$ NaCl과 diluent 0.10M $H_2SO_4$이며, recipient stream, diluent stream 및 시료의 유속은 모두 1.0ml/min이다. 황화이온 전극법에서는 시판하는 황화이온선택성 전극을 flow-through cell 속의 황화이온을 검출하는 데에 썼다. 이 방법의 최적실험조건인 황화이온 산화방지 완충제(1.0M NaOH 용액에 3.5g 아스코르브산과 7.6g $Na_2EDTA$를 용해)와 시료의 유속은 각각 1.4 ml/min와 1.0 ml/min이다.

  • PDF

Inhibition of Cell-Cycle Progression in Human Promyelocytic Leukemia HL-60 Cells by MCS-C2, Novel Cyclin-Dependent Kinase Inhibitor

  • Kim, Min-Kyoung;Cho, Youl-Hee;Kim, Jung-Mogg;Chun, Moon-Woo;Lee, Seung-Ki;Lim, Yoong-Ho;Lee, Chul-Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • 제13권4호
    • /
    • pp.607-612
    • /
    • 2003
  • To elucidate the action mechanism of MCS-C2, a novel analogue of toyocamycin and sangivamycin, its effect on the expression of cell cycle-related proteins in the human myelocytic leukemia cell line HL-60 was examined using Western blotting and a flow cytometric analysis. MCS-C2, a selective inhibitor of cyclin-dependent kinases, was found to inhibit cell growth in a time- and dose-dependent manner, and inhibits cell cycle progression by inducing the arrest at G1 and G2/M phases, in HL-60 cells. The flow cytometric analysis revealed an appreciable arrest of cells in the G2/M phase of the cell cycle after treatment with MCS-C2. The HL-60 cell population increased gradually from 13% at 0 h, to 28% at 12 h in the G2/M phase, after exposure to $2{\;}\mu\textrm{M}$ MCS-C2. Furthermore, Western blot analysis demonstrated that MCS-C2 induced the cell cycle arrest at G1 phase through the inhibition of pRb phosphorylation. Hypophosphorylated pRb accumulated after treatment with $5{\;}\mu\textrm{M}$ MCS-C2 for 12 h, whereas, the level of hyperphosphorylated pRb was reduced. Thus, treatment of the cell with MCS-C2 suppressed the hyperphosphorylated form of pRb with a commensurate increase in the hypophosphorylated form.

카드뮴에 대한 녹조류 Selenastrum capricornutum (Chlorophyceae)의 세포활력도 및 peroxidase 활성도 변화 (Changes in Cellular Viability and Peroxidase Activities of Green Algae Selenastrum capricornutum (Chlorophyceae) to Cadmium)

  • 최은주;이상구;이승진;문성경;박용석;이기태
    • Environmental Analysis Health and Toxicology
    • /
    • 제18권4호
    • /
    • pp.295-303
    • /
    • 2003
  • Physiological cellular activities responses to cadmium (Cd) exposure in green algae with several reductases activities and viability of the cell were examined. The cell division of green algae, Selenastrum capricornutum treated with 5ppm was significantly decreased than that of normal algae. The mean cell number of normal algal culture was as twice much as than that of algae at 6 days after Cd treatment. The cellular viability of algae was analysed by flow-cytometry with fluorescent dye after esterase reaction on cell membrane. The 85.35% of cellular viability of normal culture was decreased to 34.35% when algae was treated with 5 ppm of Cd at 6 days after treatment. It was considered that those method of flow-cytometry is useful tool for toxicity test on micro-organisms in the respect of identifying cellular viability. Also, the activities of both glutathione peroxidase (GPX) and ascorbate peroxidase (APX), which are indirectly react against oxidative stress through reduction of glutathione by Cd were significantly increased with 25%. It is considered that both GPX and APX are involved in the metabolic pathway of Cd -detoxification with similar portion in Selenasturm capricornutum.

QoS 측정 기반의 신경망을 이용한 연결 수락 제어기에 관한 연구 (Study on the connection admission controller using QoS measurement based neural network)

  • 이영주;변재영;정석진;김영철
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.909-912
    • /
    • 1998
  • In this paper, a new connection admission controller using neural network is presented. The controller measures traffic flow, cell loss rate, and cell delay periodically. Using those measured information, it learns the distributions of traffics of each traffic. Also the proposed controller is able to measure and manage the delays that source traffics experience through the network by using DWRR multiplexer with buffers dedicated to each traffic source. Experimental result show that the heterogeneous traffic sources with various QoS requirement.

  • PDF

CR389, a Benzoimidazolyl Pyridinone Analog, Induces Cell Cycle Arrest and Apoptosis via p53 Activation in Human Ovarian Cancer PA-1 Cells

  • Suh, Hyewon;Choi, Ko-woon;Lee, Chul-Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • 제25권3호
    • /
    • pp.418-422
    • /
    • 2015
  • In the course of screening for novel cell cycle inhibitors and apoptotic inducers, CR389, elucidated as 5-(1H-benzoimidazol-2-yl)-1H-pyridin-2-one, was generated as a new hit compound. Flow cytometric analysis and western blots of PA-1 cells treated with $60{\mu}M$ CR389 revealed an appreciable cell cycle arrest at the G2/M phase through direct inhibition of the CDK1 complex. In addition, activation of p53 via phosphorylation at Ser15 and subsequent up-regulation of p21CIP1 showed that CR389 also induces p53-dependent-p21CIP1-mediated cell cycle arrest. Furthermore, apoptotic induction in $60{\mu}M$ CR389-treated PA-1 cells is associated with the release of cytochrome c from mitochondria through up-regulation of the proapoptotic Bax protein, which results in the activation of procaspase-9 and -3, and the cleavage of poly(ADP-ribose) polymerase (PARP). Accordingly, CR389 seems to have multiple mechanisms of antiproliferative activity through p53-mediated pathways against human ovarian cancer cells. Therefore, we conclude that CR389 is a candidate therapeutic agent for the treatment of human ovarian cancer via the activation of p53.