• 제목/요약/키워드: Domain interaction

검색결과 904건 처리시간 0.022초

Notch Signal Transduction Induces a Novel Profile of Kaposi's Sarcoma-Associated Herpesvirus Gene Expression

  • Chang Hee-Soon
    • Journal of Microbiology
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    • 제44권2호
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    • pp.217-225
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    • 2006
  • Kaposi's sarcoma-associated herpesvirus (KSHV) RTA transcription factor is recruited to its responsive elements through interaction with RBP-Jk that is a downstream transcription factor of the Notch signaling pathway that is important in development and cell fate determination. This suggests that KSHV RTA mimics cellular Notch signal transduction to activate viral lytic gene expression. Here, I demonstrated that unlike other B lymphoma cells, KSHV -infected primary effusion lymphoma BCBL1 cells displayed the constitutive activation of ligand-mediated Notch signal transduction, evidenced by the Jagged ligand expression and the complete proteolytic process of Notch receptor I. In order to investigate the effect of Notch signal transduction on KSHV gene expression, human Notch intracellular (hNIC) domain that constitutively activates RBP-Jk transcription factor activity was expressed in BCBL1 cells, TRExBCBL1-hNIC, in a tetracycline inducible manner. Gene expression profiling showed that like RTA, hNIC robustly induced expression of a number of viral genes including KS immune modulatory gene resulting in downregulation of MHC I and CD54 surface expression. Finally, the genetic analysis of KSHV genome demonstrated that the hNIC-mediated expression of KS during viral latency consequently conferred the downregulation of MHC I and CD54 surface expression. These results indicate that cellular. Notch signal transduction provides a novel expression profiling of KSHV immune deregulatory gene that consequently confers the escape of host immune surveillance during viral latency.

Three Dimensional Computer Modeling of Magnetospheric Substorm

  • Min, Kyoung-W.
    • Journal of Astronomy and Space Sciences
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    • 제6권1호
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    • pp.1-15
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    • 1989
  • Magnetospheic substorm in the magnetotail region is studied numerically by means of a three dimensional MHD code. The analytic solution for the quiet magnetotail is employed as an initial configuration. The localized solar wind is modeled to enter the simulation domain through the boundaries located in the magnetotail lobe region. As a result of the interaction between the solar wind and the magnetosphere, the magnetic field lines are stretched, and the plasma sheet becomes thinner and thinner. When the current driven resistivity is generated, magnetic reconnection is triggered by this resistivity. The resulting plasma jetting is found to be super-magnetosonic. Although the plasmoid formation and its tailward motion is not quite clear as in the two dimensional simulation, which is mainly because of the numerical model chosen for the present simulation, the rarification of the plasmas near the x-point is observed. Field aligned currents are observed in the late expansive stage of the magnetospheric substorm. These field aligned currents flow from the tail toward the ionosphere on the dawn side from the ionosphere to ward the tail on the dusk side, namely in the same sense of the region 1 current. As the field aligned currents develop, it is found that the cross tail current in the earth side midnight section of the magnetic x-point is reduced.

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A Study of Role of Perceived Organizational Support among Sexual Harassment and Employees' Attitudes

  • CHOI, Youngkeun
    • The Journal of Asian Finance, Economics and Business
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    • 제7권2호
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    • pp.229-236
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    • 2020
  • Researchers generally argue that sexual harassment influence poor female employee organizational attitudes. However, these relationships have been not always observed. Depending on the organizational support theory, this study extended the content domain of sexual harassment research by examining the role of perceived organizational support, on these relationships. For this, this study used a survey method and multiple regression analyses with Korean 285 female employees. As results, first, the more unwanted sexual attention employees perceived, they were less likely to show their organizational citizenship behavior. Second, the more sexual coercion employees perceived, they were more likely to have their work-family conflict. Third, the negative relationship between unwanted sexual attention and their organizational citizenship behavior are stronger for employees low rather than high in perceived organizational support. Finally, the positive relationship between sexual coercion and work-family conflict are stronger for employees low rather than high in perceived organizational support. The findings suggest the adaptive function of perceived organizational support employees hold in organizational behavior. This is the first study to examine the interaction between perceived organizational support and sexual harassment of female workers with organizational citizenship behavior and work-family conflict. This study also provides guidance for administrative managerial practices.

열차하중으로 인한 궤도-지반의 3D 진동평가 및 저감방법에 관한 연구 (A Study on 3D Evaluation and Reduction Method for Vibration of Track-Roadbed due to Railway Load)

  • 강보순
    • 한국철도학회논문집
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    • 제14권1호
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    • pp.39-48
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    • 2011
  • 본 논문에서는 열차가 주행할 때 궤도를 통해 전달되는 진동크기가 구조물의 안전성뿐 만아니라 선로 인근주민, 가축 및 건물에게 미치는 영향을 최소화하기 위해 규정된 진동한계범위에 도달하는 가를 다양한 지반과 궤도구조물의 상호작용에 의한 3D 수치해석을 통해 정확히 예측하고 다양한 지반에 적절한 진동저감을 가져오는 궤도의 단면 및 형태를 결정하는 방법에도 이결과를 사전에 활용할 수 있도록 하였다. 예로서 열차운행으로 인해 발생되는 터널, 성토 및 교량 3종류의 서로 다른 시설물의 진동을 지반-구조물의 상호작용에 의한 3D수치해석을 통해 Spec과 비교분석하여 평가하였으며 주변 환경에 적합한 토층의 변화를 통해 진동저감방법의 한예를 수행하였다.

Speaker-Dependent Emotion Recognition For Audio Document Indexing

  • Hung LE Xuan;QUENOT Georges;CASTELLI Eric
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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    • pp.92-96
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    • 2004
  • The researches of the emotions are currently great interest in speech processing as well as in human-machine interaction domain. In the recent years, more and more of researches relating to emotion synthesis or emotion recognition are developed for the different purposes. Each approach uses its methods and its various parameters measured on the speech signal. In this paper, we proposed using a short-time parameter: MFCC coefficients (Mel­Frequency Cepstrum Coefficients) and a simple but efficient classifying method: Vector Quantification (VQ) for speaker-dependent emotion recognition. Many other features: energy, pitch, zero crossing, phonetic rate, LPC... and their derivatives are also tested and combined with MFCC coefficients in order to find the best combination. The other models: GMM and HMM (Discrete and Continuous Hidden Markov Model) are studied as well in the hope that the usage of continuous distribution and the temporal behaviour of this set of features will improve the quality of emotion recognition. The maximum accuracy recognizing five different emotions exceeds $88\%$ by using only MFCC coefficients with VQ model. This is a simple but efficient approach, the result is even much better than those obtained with the same database in human evaluation by listening and judging without returning permission nor comparison between sentences [8]; And this result is positively comparable with the other approaches.

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병렬계류된 선박의 감쇠력에 관한 실험연구 (Experimental Study on Damping of Side-by-Side Moored Vessels)

  • 김진하;홍사영;김영식;김덕수;김용수
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.160-165
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    • 2004
  • Low-frequency damping characteristics of side-by-side moored LNG-FPSO and LNGC arc investigated through a series of free decay model tests in calm water and under wind load condition. It is shown that low frequency damping of LNGC changes dramatically, sway damping increases more than six times for 4m distance condition while it decreases by $30\%$ for 20m distance compared with a single LNGC case. Simulation using the experimental data enhances the results, which demonstrates the necessity of experimental low-frequency damping coefficients for simulation of side-by-side vessels motion behavior.

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Resonance and Response of the Submerged Dual Buoy/Porous-Membrane Breakwaters in Oblique Seas

  • Kee, S.T.
    • 한국해양공학회지
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    • 제15권2호
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    • pp.22-32
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    • 2001
  • The numerical investigation of obliquely incident wave interactions with fully submerged dual buoy/porous-membrane floating breakwaters placed in parallel with spacing is studied based on linear potential theory and Darcy's law. The numerical solutions are obtained by using a discrete-membrane dynamic model and second-kind modified Bessel function distribution over the entire boundaries of fluid regions. First, numerical solutions for an idealized dual submerged system without buoys are obtained. Second, a more practical dual submerged system with membrane tension provided by buoys at its tops is investigated by the multi-domain boundary element method particularly devised for dual buoy/porous-membrane problems with gaps. The velocity potentials of wave motion are coupled with porous-membrane deformation, and solved simultaneously since the boundary condition on porous-membrane is not known in advance. The effects of varying permeability on membranes and wave characteristics are discussed for the optimum design parameters of systems previously studied. The inclusion of permeability on membrane eliminates the resonances that aggravate the breakwater performance. The system is highly efficient when waves generated by the buoys and membranes were mutually canceled and its energy at resonance frequency dissipates through fine pores on membranes.

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케이블-수중 예인체 시스템의 3차원 비선형 완전 연성해석 (3D Nonlinear Fully Coupled Simulation of Cable and Tow-fish System)

  • 고광수;이은택;안형택
    • 한국해양공학회지
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    • 제30권6호
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    • pp.458-467
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    • 2016
  • In this paper, a strongly coupled method for investigating the interaction between a cable and tow-fish is presented. The nodal position finite element method was utilized to analyze the nonlinear cable dynamics, and 6DOF equations of motion were employed to describe the 3D rigid body motion of the tow-fish. Combining cable and tow-fish systems into a single formulation allowed the two nonlinear systems to be strongly coupled into a unified nonlinear system. This strongly coupled system was numerically integrated in the time domain using a predictor/multi-corrector Newmark algorithm. To demonstrate the validity, efficacy, and applicability of the current approach, two different scenarios (virtual and sea trial) were simulated, and the simulation results were validated using the physical plausibility and the sea trial test.

SH2D4A regulates cell proliferation via the ERα/PLC-γ/PKC pathway

  • Li, Tingting;Li, Wei;Lu, Jingyu;Liu, Hong;Li, Yinghui;Zhao, Yanyan
    • BMB Reports
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    • 제42권8호
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    • pp.516-522
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    • 2009
  • SH2D4A, comprising a single SH2 domain, is a novel protein of the SH2 signaling protein family. We have previously demonstrated SH2D4A is expressed ubiquitously in various tissues and is located in the cytoplasm. In this study we investigated the function of SH2D4A in human embryonic kidney (HEK) 293 cells using interaction analysis, cell proliferation assays, and kinase activity detection. SH2D4A was found to directly bind to estrogen receptor $\alpha$ (ER$\alpha$), and prevent the recruitment of phospholipase C-$\gamma$ (PLC-$\gamma$) to ER$\alpha$. Moreover, we observed its inhibitory effects on estrogen-induced cell proliferation, involving the protein kinase C (PKC) signaling pathway. Together, these findings suggested that SH2D4A inhibited cell proliferation by suppression of the ER$\alpha$/PLC-$\gamma$/PKC signaling pathway. SH2D4A may be useful for the development of a new anti-cancer drug acting as an ER signaling modulator.

Clustered LAG-1 binding sites in lag-1/CSL are involved in regulating lag-1 expression during lin-12/Notch-dependent cell-fate specification

  • Choi, Vit Na;Park, Seong Kyun;Hwang, Byung Joon
    • BMB Reports
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    • 제46권4호
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    • pp.219-224
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    • 2013
  • The cell-fate specification of the anchor cell (AC) and a ventral uterine precursor cell (VU) in Caenorhabditis elegans is initiated by a stochastic interaction between LIN-12/Notch receptor and LAG-2/Delta ligand in two neighboring Z1.ppp and Z4.aaa cells. Both cells express lin-12 and lag-2 before specification, and a small difference in LIN-12 activity leads to the exclusive expressions of lin-12 in VU and lag-2 in the AC, through a feedback mechanism of unknown nature. Here we show that the expression pattern of lag-1/CSL, a transcriptional repressor itself that turns into an activator upon binding of the intracellular domain of Notch, overlaps with that of lin-12. Site-directed mutagenesis of LAG-1 binding sites in lag-1 maintains its expression in the AC, and eliminates it in the VU. Thus, AC/VU cell-fate specification appears to involve direct regulation of lag-1 expression by the LAG-1 protein, activating its transcription in VU cells, but repressing it in the AC.