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Thermal Dissociation and Conformational Lock of Superoxide Dismutase

  • Hong, J.;Moosavi-Movahedi, A.A.;Ghourchian, H.;Amani, M.;Amanlou, M.;Chilaka, F.C.
    • BMB Reports
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    • v.38 no.5
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    • pp.533-538
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    • 2005
  • The kinetics of thermal dissociation of superoxide dismutase (SOD) was studied in 0.05 M Tris-HCl buffer at pH 7.4 containing $10^{-4}\;M$ EDTA. The number of conformational locks and contact areas and amino acid residues of dimers of SOD were obtained by kinetic analysis and biochemical calculation. The cleavage bonds between dimers of SOD during thermal dissociation and type of interactions between specific amino acid residues were also simulated. Two identical contact areas between two subunits were identified. Cleavage of these contact areas resulted in dissociation of the subunits, with destruction of the active centers, and thus, lost of activity. It is suggested that the contact areas interact with active centers by conformational changes involving secondary structural elements.

What is learning in the Math Classroom?

  • Patton, Barba Aldis;Hutto, Nora Nelson
    • Proceedings of the Korea Society of Mathematical Education Conference
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    • 2010.04a
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    • pp.269-280
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    • 2010
  • What is learning in the math classroom? Does a new term need to be coined for learning? Is the term over-used and it has lost it meaning? The responses of one hundred four teacher candidates and graduate students were coded using the five levels researcher designed rubric which was modeled after Bloom's Taxonomy for depth of knowledge. The effects of understanding learning include the preparation of lesson plans, classroom instruction, the guiding of student learning, and the professional development of teacher leaders.

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On the Number of Modes Required to Observe Forces in Flexible Structures (유연 구조물에서 반력 평가를 위해 요구되는 모드의 수)

  • Kim, Joo-Hyung;Kim, Sang-Sup
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.562-567
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    • 2001
  • The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility, a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements with a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

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A Study on Improvement of the Stick-slip Induced an Effect Decrease of the Table Weight (테이블 중량 감소 효과에 따른 스틱슬립 개선에 관한 연구)

  • 홍성오;조규재
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.5
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    • pp.7-14
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    • 2002
  • In order to achieve high precision machine tools, the research for performance enhancement of feed drive systems is required. Development of the high speed feed drive system has been a major issue for the past few decades in machine tool indestries. Because table levitation system decrease the table weight, an effect of reaction by weight is minimized and lost motion can be removed at maximum. In case fled system is designed with drive motor, ball screw and support bearing load capacity selection, an effect of decrease of the table weight exist. So, the table weight through an effect of decrease call it into the realization of cost down. Stick-slip friction has a great influence on the contouring accuracy of CNC machine tools. In this paper table levitation system has been developed for the stick-slip in a fled drive systems.

CoA Transferase and Malonyl-CoA Decarboxylase Activity of Malonate Decarboxylase from Acinetobacter calcoaceticus

  • Byun, Hye-Sin;Kim, Yu-Sam
    • BMB Reports
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    • v.30 no.4
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    • pp.246-252
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    • 1997
  • Malonate decarboxylase from Acinetobacter calcoaceticus is shown to have malonyl-CoA: acetate CoA transferase. acetyl-CoA: malonate CoA transferase, and malonyl-CoA decarboxylase activity. These enzyme activities were elucidated by isotope exchange reactions. The enzyme modified by N-ethylmaleimide completely lost its malonate decarboxylase activity, whereas it still kept CoA transferases and malonyl-CoA decarboxylase activities. The existence of CoA transferases and malonyl-CoA decarboxylase activity is clear, but their physiological significance is obscure. The catalytic reactions for two eoA transfers and malonyl-CoA decarboxylation proceed via a cyclic mechanism, which is through two covalent intermediates, enzyme-Smalonyl and enzyme-S-acetyL proposed for malonate decarboxylation of the enzyme.

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Mathematical Thinking and Developing Mathematical Structure

  • Cheng, Chun Chor Litwin
    • Research in Mathematical Education
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    • v.14 no.1
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    • pp.33-50
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    • 2010
  • The mathematical thinking which transforms important mathematical content and developed into mathematical structure is a vital process in building up mathematical ability as mathematical knowledge based on structure. Such process based on students' recognition of mathematical concept. Developing mathematical thinking into mathematical structure happens when different cognitive units are connected and compressed to form schema of solution, which could happen through some guided problems. The effort of arithmetic approach in problem solving did not necessarily provide students the structure schema of solution. The using of equation to solve the problem is based on the schema of building equation, and is not necessary recognizing the structure of the solution, as the recognition of structure may be lost in the process of simplification of algebraic expressions, leaving only the final numeric answer of the problem.

Comparison of vibration and noise characteristic of high efficiency Insulation Panel for Transformer (변압기용 고효율 차음판의 진동 및 소음 비교)

  • Jeong, J.H.;Jang, Y.S.;Lim, D.S.;Kim, J.;Choi, B.K.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.1005-1009
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    • 2008
  • The high efficiency insulation panel for transformer construction is needed in residential area because the making noise from transformer substation in side of city is appeared a lost of problem by increasing to conserve the living environment. Therefor in this paper, first the vibration and noise characteristic of existing insulation panel is analyzed according to attached material, cork and sponge-type. Second the insulation of sound performance is compared between the existing insulation panel. And high efficiency insulation panel that is proposal in this paper.

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Studies on the Stability of Hen′s Egg Yolk Immunoglobulins (난황 항체의 안정성에 관한 연구)

  • 이경애
    • Korean journal of food and cookery science
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    • v.12 no.1
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    • pp.54-59
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    • 1996
  • Immunoglobulins (IgY) were isolated from egg yolk of hens immunized with bovine serum albumin(BSA). The stability of anti-BSA IgY against heat and pH was investigated. Antibody activity was measured by enzyme linked immunosorbent assay. IgY was relatively heat-stable and most of the antibody activity remained after heating up 65$^{\circ}C$ for 30 minutes. IgY was stable at pH 5-11. However, inactivation of IgY was observed below pH 4, or above pH 12. Inactivation of IgY proceeded rapidly at low pHs(pH 2-3). Most of the antigen binding activity was lost at low pHs probably because of some conformational changes.

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A Study on the Bow Collapse of High-Speed Passenger Craft in Collision with Bridge Pier (고속 여객선의 교각 충돌에 대한 연구)

  • 신영식;박명규
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.5 no.1
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    • pp.1-8
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    • 1999
  • During the last 10 years, the various type of high speed craft have been greatly developed, and since around of 1990 the large size of high speed passenger and/or cargo vessels are also introduced and took into the service in the various routes over the world. In a marine traffic way some bridge need to build across a rivers, cannals or a waterways. This one will be an obstruction and potential risk of collision in the way of high speed craft. Accordingly some of collision accident have been reported, which were caused by a lost control, wind and hydrodynamic forces, fog or human errors. In this paper a high speed craft having 40 m length is assumed to be collided with a circular type of bridge piers at right angle. The mode of deformation, penetration depth of collapse, impact forces, reduction of speed, loss of kinetic energy, and influence of scantlings, etc. have been calculated in each speed with a time variation to find a maximum values within a limit, and are graphically presented.

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Effect of reducing tsunami damage by installing fairing in Kesen-Bridge

  • Abukawa, Takahiro;Nakamura, Yuto;Hasegawa, Akira
    • Earthquakes and Structures
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    • v.7 no.6
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    • pp.1045-1060
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    • 2014
  • The 2011 off the Pacific coast of Tohoku Earthquake brought serious damage around the Tohoku district in Japan, and much human life and fortune were lost. Bridges were damaged by this earthquake. It was the most serious damage that the superstructures of bridges were flowed out by tsunami. Earthquakes of the same scale are predicted in other areas of Japan. It is necessary to take measures for bridges near coast. In order to understand the tsunami force acting on the bridge, hydraulic model experiments was conducted. In addition, this paper focused on fairing that is effective in wind resistant stability. Installing fairing to bridges has been verified by experiments whether it is possible to reduce the force of tsunami.