• Title/Summary/Keyword: Molecular Characteristics

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Molecular diversity and morphology of the genus Actinotrichia (Galaxauraceae, Rhodophyta) from the western Pacific, with a new record of A. robusta in the Andaman Sea

  • Wiriyadamrikul, Jutarat;Lewmanomont, Khanjanapaj;Boo, Sung Min
    • ALGAE
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    • v.28 no.1
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    • pp.53-62
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    • 2013
  • Actinotrichia is a calcified galaxauracean red algal genus with temperate and tropical distributions in the Indian and Pacific Oceans. Morphological characteristics, along with rbcL and cox1 sequences, were analyzed from specimens collected in the western Pacific and the Indian Oceans. Both rbcL and cox1 data confirmed the occurrence of A. fragilis, A. robusta, and Actinotrichia sp. in this region. The presence of A. fragilis was verified in tropical Indo-Pacific and temperate northeast Asian waters and was characterized by high genetic diversity. Although A. robusta commonly occurs in the East China Sea, we confirmed its presence on rocks and crustose algae in the subtidal zone of three islands in the Andaman Sea. Actinotrichia sp. was similar to A. calcea in morphology and distribution, but with sufficiently different sequences, thus, additional sampling over the range will enable a more realistic evaluation of its taxonomic status.

Effect of Clearance between a Rotor and Stator of a Disk-Type Drag Pump on the Pumping Performance (고속 회전하는 원판형 드래그펌프 회전익과 고정익 사이 간극이 배기 성능에 미치는 영향)

  • Kwon, Myoung-Keun;Lee, Soo-Yong;Hwang, Young-Kyu
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1640-1645
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    • 2004
  • The pumping characteristics of a single-stage disk-type drag pump ( DTDP ) are calculated,for the variation of the vertical clearance between a rotor and stator and of the radial clearance between a rotor and casing wall, by the three-dimensional direct simulation Monte Carlo (DSMC)method. The gas flow mainly belongs to the molecular transition flow region. Spiral channels of a DTDP are cut on the both the upper and lower sides of a rotating disk, but the stationary disks are planar. As a consequence of results, the vertical and radial clearances have a significant effect on the pumping performance. Experiments are performed under the outlet pressure range of 0.4 $^{\sim}$ 533 Pa. When the numerical results are compared to the experimental data, the numerical results agree well qualitatively.

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Practical Application of Electron Microscopy in Clinical Medicine (전자현미경의 임상적 응용)

  • Kim Chung-Sook
    • Applied Microscopy
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    • v.8 no.1
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    • pp.81-90
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    • 1978
  • Introduction of electron microscope in biological and medical sciences change the concept of functional and morphologic unit of biological phenomena from the cell to subcellular unit, and it formulated the basis for molecular biology and pathology. Until recently, electron microscopy has mainly been applied to basic research works. However, practical clinical application of electron microscopy is being actively tried. The major clinical fields in which electron microscopy is helpful or even essential include viral diseases, metabolic diseases, glomerular diseases and in the identification of certain types of neoplasms. A brief introduction of characteristics of each conditions are made to encourage more active application of electron microscopy in clinical medicine.

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Aptamers (nucleic acid ligands) for trypsin-like serine proteases

  • Gal, Sang-Wan;Jeong, Yong-Kee;Satoshi Nishikawa
    • Journal of Life Science
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    • v.12 no.1
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    • pp.14-18
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    • 2002
  • Subpopulations of nucleotides that bind specifically to a variety of proteins have been isolated from a population of random sequence RNA/DNA molecules. Roughly one in $10^{13}$ random sequence RNA/DNA molecules folds in such a way as to create a specific binding site for small ligands. Since the development of in vitro selection procedure, more than 50 nucleic acid ligands (aptamers) have been isolated. These molecules are very useful for the study of molecular recognition between nucleic acid and protein/organic compound. In addition to these basic studies this method gives us a dream to produce new drugs against several diseases. We focused on several aptamers which specifically binds to trypsin-like serine proteases (thrombin, human neutrophil elastase, activated protein C and NS3 protease of human hepatitis C virus) and want to introduce their structural characteristics and some functions.

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Effects of Gas-surface Interaction Models on Spacecraft Aerodynamics

  • Khlopkov, Yuri Ivanovich;Chernyshev, Sergey Leonidovich;Myint, Zay Yar Myo;Khlopkov, Anton Yurievich
    • International Journal of Aeronautical and Space Sciences
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    • v.17 no.1
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    • pp.1-7
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    • 2016
  • The influence of boundary condition of the bodies with gas flows is one of the most important problems in high-altitude aerodynamics. In this paper presents the results of the calculation of aerodynamic characteristics of aerospace vehicle using Monte-Carlo method based on three different gas-surface interaction models - Maxwell model, Cercignani-Lampis-Lord (CLL) model and Lennard-Jones (LJ) potential. These models are very sensitive for force and moment coefficients of aerospace vehicle in the hypersonic free molecular flow. The models, method and results can be used for new generation aerospace vehicle design.

Isolation and Characterization of a Methylotroph Producing 3-hydroxybutyrate-3-hydroxyvalerate Copolymer

  • JUNG HOE KIM;KIM, PIL;SEON WON KIM;GYUN MIN LEE;HYUN SOO LEE
    • Journal of Microbiology and Biotechnology
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    • v.5 no.3
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    • pp.167-171
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    • 1995
  • A bacterial strain C-02 using methanol as a carbon source was isolated from Gumi Industrial Estate and selected based on its rapid growth and capability of poly-$\beta$-hydroxybutyrate accumulation. Characteristics of strain C-02 showed that it belongs to the Methylococcaceae family, Type II subgroup. Strain C-02 could incorporate valerate into the PHB chain to form 3-hydroxybutyrate and 3-hydroxyvalerate (P(3HB-co-3HV)). Among various nutrient limitation tests, the nitrogen limitation test resulted in the highest content of P(3HB-co-3HV) per dry cell weight, 50$%$. Under the nitrogen limited condition, the average molecular weight of P(3HB-co-3HV) obtained was determined to be approximately $2.8\times 10^5$ daltons.

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Cloning and Characterization of GL-7-ACA Acylase Gene from Pseudomonas sp. GK16

  • LEE, YOUNG-SIK;HAN-CHUL YANG;SUNG-SOO PARK
    • Journal of Microbiology and Biotechnology
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    • v.6 no.6
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    • pp.375-380
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    • 1996
  • The gene coding for glutaryl-7-aminocephalosporanic acid (GL-7-ACA) acylase was cloned from Pseudomonas sp. GK16 and some of its characteristics were analyzed. The complete nucleotide sequence revealed that the putative open reading frame is 2160 bases long and encodes 720 amino acids. By SDS-PAGE three proteins, approximately corresponding to 70, 54 and 16 kDa of molecular weight, were detected in E. coli cells carrying pGAP18. The largest protein should be a precursor which is not processed yet, while the other two proteins must be derived from the precursor by the proteolytic processing.

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On Modeling and Analyzing Signaling Pathways with Inhibitory Interactions Based on Petri Net

  • Li, Chen;Suzuki, Shunichi;Ge, Qi-Wei;Nakata, Mitsuru;Matsuno, Hiroshi;Miyano, Satoru
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.348-353
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    • 2005
  • In this paper we discuss the formulation and the analysis of a signaling pathway by Petri nets. In order to explicitly and formally describe the molecular mechanisms and pathological characteristics of signaling pathways, we propose a new modeling method to construct signaling pathways on the basis of formal representation of Petri net. Our proposed extended algorithm effectively finds basic enzymic components of signaling pathways by employing T-invariants of Petri nets with considering the origination leading to an occurrence of inhibition functions than existing methods. An application of the proposed algorithm is given with the example of Interleukin-1 and Interleukin-6 signaling pathways.

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Clinical and Pathological Characteristics of Frontotemporal Lobar Degeneration(FTLD) and Molecular Genetics of Tau Protein (Frontotemporal Lobar Degeneration(FTLD)의 임상적, 병리적 특징과 타우 단백질의 분자 유전학)

  • Woo, Sung-Il
    • Korean Journal of Biological Psychiatry
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    • v.10 no.2
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    • pp.97-106
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    • 2003
  • Criticisms about amyloid cascade hypothesis of Alzheimer's disease(AD) are based on the findings, first, that the degree of dementia does not correlate with the number of plaques, and second, that the neurofibrillary tangle formation seems to predate plaque formation. In addition, neurofibrillary tangle counts correlate well with the degree of cognitive impairment. These findings suggest the independent importance of tau abnormality in AD research which is involved in the neurofibrillary tangle formation. Recently, tau pathology without amyloid deposits and mutations in tau protein gene were reported to be the major pathogenic mechanism in Pick's disease, progressive supranuclear palsy, corticobasal degeneration and FTDP-17(frontotemporal dementia and parkinsonism linked with chromosome 17). These data suggest that understanding the causes and consequences of tau dysfunction might give new clinical and therapeutic solutions to many known tauopathies.

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Electrical Breakdown In flames

  • Uhm, Han S.
    • Journal of Korean Vacuum Science & Technology
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    • v.4 no.1
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    • pp.33-37
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    • 2000
  • Properties of electrical discharge in flames and influence of plasma electrons on gas neutrals are investigated by making use of the ionization cross section of air. Frames have three distinctive features. They are hot, emit light and are weakly ionized. We investigate influence of these three characteristics of flames on the electrical breakdown. It is found that the breakdown electric field in flames is inversely proportional to the flame temperature T$\_$g/, thereby easily generating plasmas in flames. A swarm of low-energy electrons in flames would allow a significant population of electronically excited states of flame molecules to be formed. Therefore, the analysis shows that the electronic excitation of flame molecules may also considerably reduce the breakdown field. Plasma electrons generate atomic oxygen by the electron attachment of oxygen molecules in high-pressure flames. These oxygen atoms are the most reactive radicals in flames for material oxidation.

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