• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4011-4015
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• 2011

We explored the interpretation of the well-accepted correlation between the apparent peak maximum position shift and extent of molecular interactions, like hydrogen bonding and dipole-dipole interactions, based on the overlapped multiple band model. The simulation of two overlapped Lorentzian bands was carried out to interpret how the maximum position of a composite peak relates to the relative contributions of two species representing the different levels of molecular interactions, i.e., free (or very weekly bound) vs. strongly bound. To demonstrate the validity of our interpretation of the origin of the peak position shift, the temperaturedependent IR spectra of ethylene glycol were also analyzed. It was found through the analysis of simulated and experimental spectra that the apparent peak shift in certain case can be safely interpreted as the measure of the strength of hydrogen bonding. The result of this study gives a new insight to interpret molecular interactions probed by vibrational spectroscopy.

• BMB Reports
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• 제47권9호
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• pp.488-493
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• 2014

Adaptor protein FADD forms the death inducing signaling complex (DISC) by recruiting the initiating caspases-8 and -10 through homotypic death effector domain (DED) interactions. Cellular FLICE-inhibitory protein (c-FLIP) is an inhibitor of death ligand-induced apoptosis downstream of death receptors, and FADD competes with procaspase-8/10 for recruitment for DISC. However, the mechanism of action of FADD and c-FLIP proteins remain poorly understood at the molecular level. In this study, we provide evidence indicating that the death effector domain (DED) of FADD interacts directly with the death effector domain of human c-FLIP. In addition, we use homology modeling to develop a molecular docking model of FADD and c-FLIP proteins. We also find that four structure-based mutants (E80A, L84A, K169A and Y171A) of c-FLIP DEDs disturb the interaction with FADD DED, and that these mutations lower the stability of the c-FLIP DED.

• 천문학회보
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• 제39권1호
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• pp.58.1-58.1
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• 2014

We model the polarized dust emission from aligned grains by radiative torques in molecular clouds. We consider various models of molecular clouds and calculate the polarization spectrum from aligned grains by both internal and external radiation fields. We show that some polarization spectrum exhibits the bump at wavelengths ${\lambda}$ < $100{\mu}m$, which can be explained due to the polarized emission from a population of small grains aligned by internal radiation fields. Our polarization spectra can explain the anomalous spectra observed by Hildebrand et al, with the rising polarization toward short wavelengths

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.944-952
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• 1995

A generic force field approach has been applied to geometry optimization of penam and cephem crystals. The crystalline state energy and force evaluation with the universal force field (MMFF: Merck Molecular Force Field) results in good agreements with the crystallographic data. Bond lengths are usually correct to within 0.02 Å and bond angles usually to within 2.5°. The conformation of the β-lactam bicyclic rings in the crystal environment is also well reproduced. The results thus demonstrate the applicability of MMFF to modeling of newer molecular constructs in condensed phase.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.171.1-171.1
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• 2003

·The potent antitumor activities of 3-arylisoquinolines promoted us to explore the structure-activity relationship of these compounds. A series of 3-arylisoquinoline derivatives were evaluated for antitumor cytotoxicity against human lung tumor cell (A 549). For the next stage, we decided to prepare the constrained form of 3-arylisoquinolines as indeno[1,2-c]isoquinolines. As a result, diverse spectrum against human tumor cell lines was obtained. In order to study structure-activity relationship (SAT) of these compounds the comparative molecular field analysis (CoMFA) was carried out. (omitted)

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.788-791
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• 1996

A mathematical model is developed for thermal solution copolymerization of styrene and acrylonitrile in a continuous stirred tank reactor(CSTR). Computational studies are carried out with the continuous copolymerization system model developed in this work to give the monomer conversion, copolymer composition and the average molecular weights of the copolymer. By performing the dynamic analysis of the reaction system, the polymer properties against the changes in the operating conditions are determined quantitatively. The cascade PID and fuzzy controller show satisfactory performances for both set point tracking and disturbance rejection. Especially, the fuzzy controller is superior to the PID controller.

• Molecules and Cells
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• 제28권2호
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• pp.81-85
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• 2009

$Na^+-H^+$ exchanger (NHE) is the main acid extruder in cardiac myocytes. We review the experimental findings of ion-dependency of NHE activity, and the mathematical modeling developed so far. In spite of extensive investigation, many unsolved questions still remain. We consider that the precise description of NHE activity with mathematical models elucidates the roles of NHE in maintaining ionic homeostasis, especially under pathophysiological conditions.

• 한국당과학회:학술대회논문집
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• 한국당과학회 2006년도 제1회 연례학술대회
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• pp.31-31
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• 2006

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2087-2092
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• 2009

We performed molecular dynamics simulations on dimyristoylphosphatidylcholine lipid bilayer with 50 mol% halothane. The structural properties, electron density profile, segmental order parameter of acyl chains, headgroup orientation distribution, water dipole orientation distribution, have been examined. Overall the effects of the halothane molecules on structural properties of DMPC lipid bilayer were found to be small. The electron density profiles, the segmental order parameter, the headgroup orientation, the water dipole orientation were not affected significantly by the halothane molecules. Pressure tensor calculations shows that the lateral pressure increases at the hydrocarbon tail region and the headgroup region, and decreases at the water-headgroup interfacial region.

• 반도체디스플레이기술학회지
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• 제12권1호
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• pp.61-65
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• 2013

We investigated the wearable dynamics of diamond spherical abrasive during the substrate surface polishing under the pad compression via classical molecular dynamics modeling. We performed three-dimensional molecular dynamics simulations using the Morse potential functions for the copper substrate and the Tersoff potential function for the diamond abrasive. The pad hardness had a big impact on the wearable dynamics of the abrasive. The moving speed of the abrasive decreased with increasing hardness of the pad. As the hardness decreased, the abrasive was indented into the pad and then the sliding motion of the abrasive was increased. So the pad hardness was greatly influenced on the slide-to-roll ratio as well as the wearable rate.