• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.26-26
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• 2003

The backbone dynamics of ketosteroid isomerase, a homodimeric enzyme with 125 amino acid residues per subunit, has been studied in the presence/absence of a steroid ligand and 5％ trifluoroethanol (TFE) by $^{15}$ M relaxation measurements. The relaxation data were analyzed using the model-free formalism to extract the model-free parameters (S$^2$, $\tau$$_{e}$, and R$_{ex}$ ). The results show that a large number of the residues, particularly those involved in the dimer interaction, exhibit reduced order parameters (S$^2$) in the steroid-bound enzyme, indicating the increased high-frequency (pico- to nanosecond) motions in the interface region upon ligand binding. The results also show that that the presence of 5 ％ TFE in free enzyme causes little change or slight increase in the order parameters for a number of residues in the dimer interface region. However, the majority of the residues in free enzyme exhibit reduced order parameters in the presence of 5 ％ TFE, indicating that the increase in entropy is partially responsible for the increased stability of KSI by 5％ TFE.E.E.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.12
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• pp.1359-1365
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• 2011

The changes of ablation characteristics with respect to laser parameters and material parameters during pulsed laser ablation of solids were discussed with experimental results. Although laser wavelength, laser pulse width, and laser pulse energy are the primary factors to be considered, it is shown that other parameters such as laser spot size and material properties also critically influence on the ablation results. It is further demonstrated that the microstructural characteristics of the target can lead to completely different ablation rate and surface morphology.

• Coupled systems mechanics
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• v.6 no.3
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• pp.229-249
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• 2017

A new technique to mitigate irregular buildings with soil structure interaction (SSI) effect subjected to critical seismic waves is presented. The L-shape in plan irregular building for various reasons was selected, subjected to seismic a load which is a big problem for structural design especially without separation gap. The L-shape in plan building with different dimensions was chosen to study, with different rectangularity ratios and various soil kinds, to show the effect of the irregular building on the seismic response. A 3D building subjected to critical earthquake was analyzed by structural analysis program (SAP2000) fixed and with SSI (three types of soils were analyzed, soft, medium and hard soils) to find their effect on top displacement, base shear, and base torsion. The straining actions were appointed and the treatment of the effect of irregular shape under critical earthquake was made by using tuned mass damper (TMD) with different configurations with SSI and without. The study improve the success of using TMDs to mitigate the effect of critical earthquake on irregular building for both cases of study as fixed base and raft foundation (SSI) with different TMDs parameters and configurations. Torsion occurs when the L-shape in plan building subjected to earthquake which may be caused harmful damage. TMDs parameters which give the most effective efficiency in the earthquake duration must be defined, that will mitigate these effects. The parameters of TMDs were studied with structure for different rectangularity ratios and soil types, with different TMD configurations. Nonlinear time history analysis is carried out by SAP2000 with El Centro earthquake wave. The numerical results of the parametric study help in understanding the seismic behavior of L-shape in plan building with TMDs mitigation system.

• Biomolecules & Therapeutics
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• v.6 no.4
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• pp.389-394
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• 1998

Cyclosporine (CsA) is a major immunosuppressive drug used widely to prevent organ allograft rejection. fits potential organotoxicity by prolonged use is known to cause both direct tissue damage and indirect pharmacokinetic interactions with other drugs. This study was performed to determine the effect of nicardipine (NCP) on the pharmacokinetic parameters of CsA in Sprague-Dawley rats. Each rat was administered with CsA in saline-treated group or in NCP-treated group which was pretreated with NCP (5 mg/kg/12 hours, i.p.) for 6 days. The plasma CsA concentration were analyzed by reversed HPLC: UV system at 0.5, 1, 2, 4, 6, and 8 hours after bolus injection of CsA (10 mg/kg). Pharmacokinetic parameters (mean$\pm$ SD, n=7) such as initial plasma concentration (C(0)), mean residence time (MRT), steady-state volume of distribution (Vdss), terminal half-life (t$\frac{1}{2}$($\beta$)) and plasma clearance (CLp) of CsA in each groups (saline-group vs NCP-group) were determined as follows: C(0) (5.66$\pm$ 1.98 vs 17.98$\pm$2.36, p<0.01); Vdss (2.68$\pm$ 1.6 vs 0.94 $\pm$ 0.25, p<0.01); CLp (0.53 $\pm$0.18 vs 0.21 $\pm$0.06, p<0.01). Therefore, Our results indicate that nicardipine significantly affects the pharmacokinetic parameters of cyclosporme, especially C(0), Vdss, and CLp in NCP-treated group. We suggest that the significant pharmacokinetic interaction between cyclosporine and nicardipine should be considered and cyclosporine level should be closely monitored and dosage reduction made as necessary in clinical situation that was coadministered with CsA and NCP.

• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.45-51
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• 1985

Rate constants and activation parameters for the methanolysis of t-butyl halide (t-BuCl, t-BuBr, t-BuI) in various MeOH-DMSO mixtures were measured by conductometric method. Taft's solvatochromic parameters, such as polarity-polarizability(SPP's), ${\pi}^{\ast}$, hydrogen bond donor (HBD) acidity, ${\alpha}$, and hydrogen bond acceptor (HBA) basicity, ${\beta}$ of the solvents, were determined by the so called solvatochromic method using five indicators. The variation of methanolysis rate with the solvent composition was discussed on the basis of the activation parameters and the correlation of the rates with the solvatochromic parameters. It is concluded that the polarity-polarizability, HBD acidity and HBA basicity of the mixtures had an effect on the ionization of t-butyl halide cooperatively, also that the specific interaction between the leaving groups and the solvents, such as ion-dipole and hydrogen bond acceptor-donor interaction, is the most important factor of solvent effects on the stabilization of transition states.

• Journal of Korean Society of Steel Construction
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• v.14 no.6
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• pp.803-811
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• 2002

Current composite steel and concrete bridges are designed using full-interaction theory assuming there is no relative slip, between the steel and concrete components along their interface, because of the complexities of partial-interaction analysis techniques. However, in the assessment of existing composite bridges this simplification may not be warranted as it is often necesary to extract the correct capacity and endurance from the structure. This may only be achieved using partial-interaction theory which tuly reflects the behaviour of the structure. In this paper, Parametric analyses have been carried out in order to confirm the partial-interaction curvatures with deflection effect using the finite element method. Therefore, the model is considered for simply supported steel and concrete composite bridges with a uniform distribution of connectors subjected to a single concentrated load. For the case studies, this study applicate a parameters such as the number and space of stud shear connector and elastic modulus of concrete slabs. From this study, it is known that partial-interaction effect was in the increase to the increasing the deflection of composite bridges, and stiffness and strength of slab concrete considering the occurrence of crack effect seriously to the partial-interaction behavior.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.255-259
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• 2022

The new social reality emerging amid the global rise of communication links and integration processes acutely emphasizes the problems of communication in large and small social systems. The method of their communication becomes one of the keys to ensuring global security. It has become the mission of humanitarian education to prepare the younger generations for life in a changing world with no image of the future and increasing uncertainty. In psychological and pedagogical research, there is a growing scientific interest in the problems of interaction of the individual with the social environment. The mental trace of a person's practice in society shapes the experience of social interaction, which constitutes simultaneously the source, tool, and condition for the emergence and development of personality. The study outlines the methodological foundations for the study of individual experiences of social interaction. A hypothesis about the productivity of the functional matrix method is tested. Materials for the training of specialists in the humanities include interdisciplinary approaches to the study and transformation of the experience of social interaction and systematic methodology for the study of complex objects. Fundamental to the study is the systematic-dialectical method, and the matrix method is employed as the instrumental-technological method. The paper presents the results of a multidisciplinary overview of scientific literature concerning the essential characteristics and functions of social interaction and the respective experience. The overview points to the fragmented nature of scientific understanding of the elements of experience outside its integrity and systemic properties. Based on the formula "personality interacts with the social environment", the study presents an algorithm for the application of a systematic methodology for the study of complex objects, which made it possible to identify the system parameters of experience at three levels of cognition and develop the reference structural and functional matrices for the didactic system of its pedagogical enrichment.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.63-68
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• 1987

In this study, a pantograph leg of the four legged walking vehicle is analysed with regard to mechanical energy consumption. Energy efficiency of the vehicle is estimated in terms of specific resistance varying body height, stride length and walking speed. The interaction between specific resistance and the parameters is investigated.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.65-70
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• 2008

The capacity spectrum method (CSM) is a deterministic seismic analysis approach wherein the expected seismic response of a structure is established as the intersection of the demand and capacity curves. Recently, there are a few studies about a probabilistic CSM where uncertainties in design factors such as material properties, loads, and ground motion are being considered. However, researches show that soil-structure interaction also affects the seismic responses of structures. Thus, their uncertainties should also be taken into account. Therefore, this paper presents a probabilistic approach of using the CSM for seismic analysis considering uncertainties in soil properties. For application, a reinforced concrete bridge column structure is employed as a test model. Considering the randomness of the various design parameters, the structure's probability of failure is obtained. Monte Carlo importance sampling is used as the tool to assess the structure's reliability when subjected to earthquakes. In this study, probabilistic CSM with and without consideration of soil uncertainties are compared and analyzed. Results show that the analysis considering soil structure interaction yields to a greater probability of failure, and thus can lead to a more conservative structural design.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.446-452
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• 2016

Pharmacokinetic interaction of chrysin, a flavone present in honey, propolis and herbs, with caffeine was investigated in male Sprague-Dawley rats. Because chrysin inhibited CYP1A-selective ethoxyresorufin O-deethylase and methoxyresorufin O-demethylase activities in enriched rat liver microsomes, the pharmacokinetics of caffeine, a CYP 1A substrate, was studied following an intragastric administration with 100 mg/kg chrysin. In addition to the oral bioavailability of chrysin, its phase 2 metabolites, chrysin sulfate and chrysin glucuronide, were determined in rat plasma. As results, the pharmacokinetic parameters for caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) were not changed following chrysin treatment in vivo, despite of its inhibitory effect on CYP 1A in vitro. The bioavailability of chrysin was found to be almost zero, because chrysin was rapidly metabolized to its sulfate and glucuronide conjugates in rats. Taken together, it was concluded that the little interaction of chrysin with caffeine might be resulted from the rapid metabolism of chrysin to its phase 2 metabolites which would not have inhibitory effects on CYP enzymes responsible for caffeine metabolism.