• Title/Summary/Keyword: Cell complex

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Regulatory T Cells and Infectious Disease

  • Rouse, Barry T.;Sehrawat, Sharvan
    • IMMUNE NETWORK
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    • v.7 no.4
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    • pp.167-172
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    • 2007
  • Various cell types that express regulatory function may influence the pathogenesis of most and perhaps all infections. Some regulatory cells are present at the time of infection whereas others are induced or activated in response to infection. The actual mechanisms by which different types of infections signal regulatory cell responses remain poorly understood. However a most likely mechanism is the creation of a microenvironment that permits the conversion of conventional T cells into cells with the same antigen specificity that have regulatory function. Some possible means by which this can occur are discussed. The relationship between regulatory cells and infections is complex especially with chronic situations. The outcome can either be of benefit to the host or damage the disease control process or in rare instances appears to be a component of a finely balanced relationship between the host and the infecting agent. Manipulating the regulatory cell responses to achieve a favorable outcome of infection remains an unfulfilled objective of therapeutic immunology.

Dynamic Transient Phenomena of a Proton Exchange Membrane Fuel Cells (PEMFC 연료전지의 과도현상 특성)

  • Lee, Ying;Choi, Yong-Sung;Zhang, You-Sai;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.203-203
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    • 2010
  • The proton exchange membrane fuel cell (PEMFC) is different from the normal power supply, and it is a nonlinear, multi-input, strong coupling, the complex dynamic system with large time delay. At present, many studies on the content of the fuel cell fuel cells focus on a static process, this paper analyzed in subsequent sections of the process of fuel cell dynamic response time of transition, and then it found the method to reduce the response time during the process of load change to ensure that the stability of output power.

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Constitutive Equations for Three Dimensional Circular Braided Glass Fiber Reinforced Composites Using Cell Modeling Method (셀 방법을 이용한 3차원 원형 브레이드 유리 섬유 강화 복합 재료의 구성 방정식)

  • 이원오;정관수
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2003.10a
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    • pp.71-74
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    • 2003
  • The cell modeling homogenization method to derive the constitutive equation considering the microstructures of the fiber reinforced composites has been previously developed for composites with simple microstructures such as 2D plane composites and 3D rectangular shaped composites. Here, the method has been further extended for 3D circular braided composites, utilizing B-spline curves to properly describe the more complex geometry of 3D braided composites. For verification purposes, the method has been applied for orthotropic elastic properties of the 3D circular braided glass fiber reinforced composite, in particular for the tensile property. Prepregs of the specimen have been fabricated using the 3D braiding machine through RTM (resin transfer molding) with epoxy as a matrix. Experimentally measured uniaxial tensile properties agreed well with predicted values obtained fer two volume fractions.

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The Application of Cartesian Cut Cell Method for a High-Voltage GCB (분할격자법을 이용한 초고압 가스차단기 유동해석)

  • Lee Jong C.;Ahn Heui-Sub;Kim Youn J.
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.91-94
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    • 2002
  • It is important to develop new effective technologies for increasing the interruption capacity and reducing the size of a GCB (Gas Circuit Breaker). It is not easy to test the real GCB model in practice as in theory. Therefore, a simulation tool based on a CFD (Computational Fluid Dynamics) algorithm has been developed to facilitate an optimization of the interrupter. But the choice of grid is not at all trivial in the complicated geometries like a GCB. In this paper, we have applied a CFD-CAD integration using Cartesian cut-cell method, which is one of the grid generation techniques for dealing with complex and multi-component geometries.

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Efficient Calculation of Distance Fields Using Cell Subdivision (셀 분할을 이용한 거리장의 효율적 계산)

  • Yoo, Dong-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.3
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    • pp.147-156
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    • 2008
  • A new approach based on cone prism intersection method combined with sorting algorithm is proposed for the fast and robust signed distance field computation. In the method, the space bounding the geometric model composed of triangular net is divided into multiple smaller cells. For the efficient calculation of distance fields, valid points among the triangular net which will generate minimum distances with current cell are selected by checking the intersection between current cell and cone prism generated at each point. The method is simple to implement and able to achieve an order of magnitude improvement in the computation time as compared to earlier approaches. Further the method is robust in handling the traditional sign problems. The validity of the suggested method was demonstrated by providing numerous examples including Boolean operation, shape deformation and morphing of complex geometric models.

Effect of cell growth inhibition by eukaryotic initiation factor 2 derived peptides (진핵생물 개시인자 유래 펩타이드의 세포 성장 억제 효능)

  • Yu, HanJin;Lim, Kwang Suk
    • Journal of Industrial Technology
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    • v.40 no.1
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    • pp.1-6
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    • 2020
  • In the process of protein transcription and translation, various protein complexes bind to DNA, and all processes are precisely controlled. Among the proteins constituting this complex, a peptide derived from eukaryotic initiation factor (eIF) 2 was synthesized. In addition, in order to increase the efficiency of transduction of this peptide into cells, peptides with polyarginine, one of the protein transduction domains (PTD), were synthesized. Cell growth inhibition was confirmed in HER2 positive breast cancer (SK-Br-3) and HER2 negative breast cancer (MDA-MB-231), and cardiomyocytes (H9c2). The peptide with polyarginine had high transduction efficiency in all cells, and had excellent cancer cell growth inhibitory effects. The peptide used in this study might be useful peptide therapeutics for the treatment of cancer through future research.

An object-oriented approach to the cell activity representation for an intelligent manufacturing system (IMS)

  • Choi, Kyunghyun;Cho, Kyu-Kab
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.39-42
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    • 1995
  • A new methodology for representing the interaction between machines and the interlock signals required in FMCs has been developed. Object-Oriented Philosophies (OOPs) lend themselves to the development of such a scheme. A methodology developed here regards the tasks to be performed by the cell or any of its constituent machines for being primal. Sensory signals indicating the changes of state pf machines are used to trigger or initiate tasks. A task may be simple and require a relatively short time to execute, or may be complex and lengthy. This methodology may be depicated by a set of diagrams called Task Initiation Diagram (TID) and their accompanying rules.

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Effect of complex mechanical stimuli for MC3T3-E1 cells (MC3T3-E1 세포에 대한 복합 기계적 자극의 영향)

  • Kang, Kyung-Shin;Lee, Seung-Jae;Cho, Dong-Woo
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1700-1703
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    • 2008
  • The purpose of this study was to examine the effects of various mechanical stimuli for MC3T3-E1 cells. Among the several mechanical stimulations, we focused on compressive stain and ultrasound. In this study, we developed a bioreactor capable of applying controlled stimuli to scaffolds. PLLA/PCL scaffold was fabricated by using salt-leaching method. We performed dynamic cell culture using preosteoblasts MC3T3-E1 cells with 1MHz, 30mW/cm2 ultrasound and 10% of compressive strain. Result of CCK-8 analysis at 1, 4, 7, 10 days showed that mechanical stimuli had no significant effect for cell proliferation. However, those stimuli influenced ALP(Alkaline phopatase) activity, which is one of differentiation marker.

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Cellular and molecular change including nerve regeneration after peripheral nerve injury (말초신경 손상 후 재생과 관련된 세포적, 분자적 변화)

  • Baek Su-Jeong;Kim Dong-Hyun;Kim Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.12 no.3
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    • pp.415-432
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    • 2000
  • In mammals. axotomy of peripheral nerve leads to a complex. These events include swelling of cell body, disappearance of Nissl substance. Proximal and distal axon undergoes a variable deriable degree of traumatic degeneration and wallerian degeneration, respectively. Nerve injury may result in cell death or regeneration. Molecular changes include proliferation of Schwann cells, upregulation of neurotropism, neural cell adhesion molecules and cytokine. Also growth cone plays an essential role in axon guidance through interaction of cytoskeleton. We review cellular and molecular events after nerve injury and describe nerve regeneration and associated proteins.

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Heat Shock Responses for Understanding Diseases of Protein Denaturation

  • Kim, Hee-Jung;Hwang, Na Rae;Lee, Kong-Joo
    • Molecules and Cells
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    • v.23 no.2
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    • pp.123-131
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    • 2007
  • Extracellular stresses induce heat shock response and render cells resistant to lethal stresses. Heat shock response involves induction of heat shock proteins (Hsps). Recently the roles of Hsps in neurodegenerative diseases and cancer are attracting increasing attention and have accelerated the study of heat shock response mechanism. This review focuses on the stress sensing steps, molecules involved in Hsps production, diseases related to Hsp malfunctions, and the potential of proteomics as a tool for understanding the complex signaling pathways relevant to these events.