• Title/Summary/Keyword: conserved

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Hamilton제s Principle for the Free Surface Waves of Finite Depth (유한수심 자유표면파 문제에 적용된 해밀톤원리)

  • 김도영
    • Journal of Ocean Engineering and Technology
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    • v.10 no.3
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    • pp.96-104
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    • 1996
  • Hamilton's principle is used to derive Euler-Lagrange equations for free surface flow problems of incompressible ideal fluid. The velocity field is chosen to satisfy the continuity equation a priori. This approach results in a hierarchial set of governing equations consist of two evolution equations with respect to two canonical variables and corresponding boundary value problems. The free surface elevation and the Lagrange's multiplier are the canonical variables in Hamilton's sense. This Lagrange's multiplier is a velocity potential defined on the free surface. Energy is conserved as a consequence of the Hamiltonian structure. These equations can be applied to waves in water of finite depth including generalization of Hamilton's equations given by Miles and Salmon.

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DNA Light-strand Preferential Recognition of Human Mitochondria Transcription Termination Factor mTERF

  • Nam, Sang-Chul;Kang, Chang-Won
    • BMB Reports
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    • v.38 no.6
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    • pp.690-694
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    • 2005
  • Transcription termination of the human mitochondrial genome requires specific binding to termination factor mTERF. In this study, mTERF was produced in E. coli and purified by two-step chromatography. mTERF-binding DNA sequences were isolated from a pool of randomized sequences by the repeated selection of bound sequences by gel-mobility shift assay and polymerase chain reaction. Sequencing and comparison of the 23 isolated clones revealed a 16-bp consensus sequence of 5'-GTG$\b{TGGC}$AGANCCNGG-3' in the light-strand (underlined residues were absolutely conserved), which nicely matched the genomic 13-bp terminator sequence 5'-$\b{TGGC}$AGAGCCCGG-3'. Moreover, mTERF binding assays of heteroduplex and single-stranded DNAs showed mTERF recognized the light strand in preference to the heavy strand. The preferential binding of mTERF with the light-strand may explain its distinct orientation-dependent termination activity.

"25-kDa Thiol Peroxidase" (TPx II) Acts as a "Housekeeping" Antioxidant

  • Cha, Mee-Kyung;Kim, II-Han
    • BMB Reports
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    • v.32 no.5
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    • pp.506-510
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    • 1999
  • The newly-found thiol peroxidases (TPx) with a conserved cysteine as the primary site of catalysis are capable of catalyzing the thiol-dependent reduction of peroxides. However, the cellular distributions of the isoforms remain poorly understood. As a first step in understanding the physiological functions of the TPx isoforms, we examined the cellular and tissue distribution of the isoenzymes in various bovine tissues. The tissue distributions of TPx isoenzymes indicate that two types of TPx are widely distributed throughout all of the tested tissues. These two forms are the predominant proteins, with levels of the proteins being quite different from each other. The level of predominant TPx proteins, named type II (TPx II) and type V (TPx V), appeared to be very different with respect to tissue type. The cellular distribution and level of TPx isoenzymes also varied with the types of cells. Immunoblot analysis of the mitochondrial and cytosol fractions from various tissues indicates that TPx III is a unique mitochondrial form. Based on the different tissue and cellular distribution of TPx isoenzymes, we discuss the physiological function of TPx isoenzymes, especially the ubiquitous TPx II.

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Characterization and function of human Ly-6/uPAR molecules

  • Kong, Hyun Kyung;Park, Jong Hoon
    • BMB Reports
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    • v.45 no.11
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    • pp.595-603
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    • 2012
  • Human Ly-6/uPAR molecules are a superfamily composed of two subfamilies; one is the membrane bound proteins with a GPI-anchor and the other are secreted proteins without the GPI-anchor. Ly-6/uPAR molecules have remarkable amino acid homology through a distinctive 8-10 cysteine-rich domain that is associated predominantly with O-linked glycans. These molecules are encoded by multiple tightly linked genes located on Chr. 8q23, and have a conserved genomic organization. Ly-6/uPAR molecules have an interesting expression pattern during hematopoiesis and on specific tumors indicating that Ly-6/uPAR molecules are associated with development of the immune system and carcinogenesis. Thus, Ly-6/uPAR molecules are useful antigens for diagnostic and therapeutic targets. This review summarizes our understanding of human Ly-6/uPAR molecules with regard to molecular structure as well as what is known about their function in normal and malignant tissues and suggest Ly-6/uPAR molecules as target antigens for cancer immunotherapy.

The role of extracellular biophysical cues in modulating the Hippo-YAP pathway

  • Mo, Jung-Soon
    • BMB Reports
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    • v.50 no.2
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    • pp.71-78
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    • 2017
  • The Hippo signaling pathway plays an essential role in adult-tissue homeostasis and organ-size control. In Drosophila and vertebrates, it consists of a highly conserved kinase cascade, which involves MST and Lats that negatively regulate the activity of the downstream transcription coactivators, YAP and TAZ. By interacting with TEADs and other transcription factors, they mediate both proliferative and antiapoptotic gene expression and thus regulate tissue repair and regeneration. Dysregulation or mutation of the Hippo pathway is linked to tumorigenesis and cancer development. Recent studies have uncovered multiple upstream inputs, including cell density, mechanical stress, G-protein-coupled receptor (GPCR) signaling, and nutrients, that modulate Hippo pathway activity. This review focuses on the role of the Hippo pathway as effector of these biophysical cues and its potential implications in tissue homeostasis and cancer.

NUMERICAL MODELING FOR FLAME STABILIZATION OF GAS TURBINE COMBUSTOR (가스터빈 엔진의 화염안정성에 대한 수치모델링)

  • Kang Sungmo;Kim Yongmo;Chung Jae-Hwa;Ahn Dal-Hong
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.201-206
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    • 2005
  • In order to realistically represent the complex turbulence-chemistry interaction at the partially premixed turbulent lifted flames encountered in the gas turbine combustors, the combined conserved-scalar/level-set flamelet approach has been adopted. The parallel unstructured-grid finite-volume method has been developed to maintain the geometric flexibility and computational efficiency for the solution of the physically and geometrically complex flows. Special emphasis is given to the swirl effects on the combustion characteristics of the lean-premixed gas turbine combustor. Numerical results suggest that the present approach is capable of realistically simulating the combustion characteristics for the lean-premixed gas turbine engines and the lifted turbulent jet flame with a vitiated coflow.

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Coupling characteristics of localized modes of line defects in two-dimensional photonic crystals (2차원 광자결정 도파로에서 결함모드의 결합특성)

  • Cho, Dae-Hee;Park, Hye-Young;Kee, Chul-Sik;Lim, H.
    • Proceedings of the KIEE Conference
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    • 2003.10a
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    • pp.270-272
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    • 2003
  • We have investigated the coupling characteristics of localized modes of line defect i.e., guided modes, in photonic crystals. The parity of the coupled guided modes is not conserved when the distance between the line defects changes. By comparing the coupling characteristics of localized modes without the oscillatory nature such as cavity modes of metallic Fabry-Parot cavities with those of localized modes in photonic crystals, we confirmed that this parity nonconservation is attributed to the oscillatory nature of the evanescent waves of localized modes in photonic crystals.

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A Study to Guest House Plan for Positive Inflrction of Modern Architecture - Focused on Jung Myeung Jun - (근대건축물의 적극적 활용을 위한 게스트하우스 계획에 관한 연구 - 중명전(重明殿)을 중심으로 -)

  • Lee, Keun-Hye;Oh, In-Wook
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.05a
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    • pp.107-112
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    • 2006
  • Current city that we live in exist many modern architecture have historical meaning and high value. This modern architecture is disappearing because study - definite thesis of concept, division of the time - of preservation wasn't advanced fully and we have the feeling of being victimzed for Japanese imperialism, in addition to lack of recognition for cultural treasure value. These days, a growing number of people tend to focus on preservation and uses of cultural properties including mordern architectures. Therefore, this study aims to figure out constructive uses of mordern architectures by purposing analysis and preservation methods with a selected architectures which deserve to be conserved.

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Multifactorial Regulation of G Protein-Coupled Receptor Endocytosis

  • Zhang, Xiaohan;Kim, Kyeong-Man
    • Biomolecules & Therapeutics
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    • v.25 no.1
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    • pp.26-43
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    • 2017
  • Endocytosis is a process by which cells absorb extracellular materials via the inward budding of vesicles formed from the plasma membrane. Receptor-mediated endocytosis is a highly selective process where receptors with specific binding sites for extracellular molecules internalize via vesicles. G protein-coupled receptors (GPCRs) are the largest single family of plasma-membrane receptors with more than 1000 family members. But the molecular mechanisms involved in the regulation of GPCRs are believed to be highly conserved. For example, receptor phosphorylation in collaboration with ${\beta}$-arrestins plays major roles in desensitization and endocytosis of most GPCRs. Nevertheless, a number of subsequent studies showed that GPCR regulation, such as that by endocytosis, occurs through various pathways with a multitude of cellular components and processes. This review focused on i) functional interactions between homologous and heterologous pathways, ii) methodologies applied for determining receptor endocytosis, iii) experimental tools to determine specific endocytic routes, iv) roles of small guanosine triphosphate-binding proteins in GPCR endocytosis, and v) role of post-translational modification of the receptors in endocytosis.

Identification and Differentiation of Cucumber Mosaic Virus Isolated from Forsythia koreana (CMV-Fk) Using PCR Techniques (PCR기법을 이용한 오이 모자이크 바이러스 개나리 분리주(CMV-Fk)의 동정과 구분)

  • 이상용;박선정;최장경
    • Korean Journal Plant Pathology
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    • v.14 no.4
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    • pp.308-313
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    • 1998
  • Reverse transcription and polymerase chain reaction (RT-PCR) techiniques were used to identification and differentiation of cucumber mosaic virus isolated from Forsythia koreana (CMV-Fk). RT-PCT used by two set of 20-mer primers one was CMV-common primers and another was CMV subgroup I-specific primers designed in a conserved region of the 3' end of CMV RNA3, amplified about 490 bp and 200 bp DNA fragments from CMV-Fk, respectively. CMV could be detected by RT-PCR at a dilution as low as 10-4 in forsythia crude sap extracts. Restriction enzyme analysis of RT-PCR products using EcoRI and MspI showed that CMV-Fk belonged to CMV subgroup I. But, analysis of RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR) showed heterogeneity of RNA3 between CMV-Fk and CMV-Y as a member of subgroup I.

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