• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.103-106
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• 2000

The electronic properties of carbon nanotube are currently the focus of considerable interest. In this paper, the electronic properties of finite length effect in carbon nanotube for cabon nanoscale device is presented. To calculate the electronic properties of carbon nanotube, Empirical potential method (Brenner' hydrocarbon potential) for carbon and Tight binding molecular dynamic (TBMD) simulation are used. As a result of study, we have known that the value of the band gap decreases with increasing the length of the tube. The energy band gap of (6, 6) armchair carbon nanotube have the ranges between 0.3 eV and 2.5 eV. Also, our results were compared with the results of the other computational techniques. As that result, our results are very well united.

• 약학회지
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• 제33권2호
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• pp.87-100
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• 1989

Salicylic acids as anti-inflammatory agents were analyzed by ab initio, quantum chemical methods to study the possible modes of binding to the receptor. As the result of multiple regression analysis of reactivity indices and interpretation of normalized frontier orbital charges of drugs, potency seems to be related to energy of HOMO and LUMO at the 5 position of benzene ring, and in the 5-phenyl substituted case, the para position of substituting ring is important. The binding occurs first at the positive site of its receptor. The charge density exhibited by the frontier orbitals suggests that charge moves from receptor site to carboxyl group. The electrostatic orientation effect makes an important contribution to the binding of the active molecules to their receptors. Also the electrostatic potential model may be able to rationalize the source of activity or inactivity of the drugs under investigation.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1459-1464
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• 2004

The purpose of this research was to investigate the potential use of cheese whey protein (CWP), a cheese by-product. The physiological activity of calcium-binding peptides in CWP may be used as a food additive that prevents bone disorders. This research also examined the characteristics of calcium-binding peptides. After the CWP was heat treated, it was hydrolyzed by trypsin. Then calcium-binding peptides were separated and purified by ion-exchange chromatography and reverse phase HPLC, respectively. To examine the characteristics of the purified calcium-binding peptides, amino acid composition and amino acid sequence were analyzed. Calcium-binding peptides with a small molecular weight of about 1.4 to 3.4 kDa were identified in the fraction that was flowed out from 0.25 M NaCl step gradient by ion-exchange chromatography of tryptic hydrolysates. The results of the amino acid analysis revealed that glutamic acid in a calcium-binding site took up most part of the amino acids including a quantity of proline, leucine and lysine. The amino acid sequence of calcium-binding peptides showed Phe-Leu-Asp-Asp-Asp-Leu-Thr-Asp and Ile-Leu-Asp-Lys from $\alpha$-LA and Ile-Pro-Ala-Val-Phe-Lys and Val-Tyr-Val-Glu-Glu-Leu-Lys from ${\beta}$-LG.

• Transactions on Electrical and Electronic Materials
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• 제14권6호
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• pp.329-333
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• 2013

SiOC films were prepared by capacitively coupled plasma chemical vapor deposition, and the correlation between the binding energy by X-ray photoelectron spectroscopy and Arrhenius equation for ionization energy was studied. The ionization energy decreased with increase of the potential barrier, and then the dielectric constant also decreased. The binding energy decreased with increase of the potential barrier. The dielectric constant and electrical characteristic of SiOC film was obtained by Arrhenius equation. The dielectric constant of SiOC film was decreased by lowering the polarization, which was made from the recombination between opposite polar sites, and the dissociation energy during the deposition. The SiOC film with the lowest dielectric constant had a flat surface, which depended on how carbocations recombined with other broken bonds of precursor molecules, and it became a fine cross-linked structure with low ionization energy, which contributed to decreasing the binding energy by Si 2p, C 1s electron orbital spectra and O 1s electron orbital spectra. The dielectric constant after annealing decreased, owing to the extraction of the $H_2O$ group, and lowering of the polarity.

• BMB Reports
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• 제48권12호
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• pp.643-644
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• 2015

In eukaryotes, small RNAs play important roles in both gene regulation and resistance to viral infection. Argonaute proteins have been identified as a key component of the effector complexes of various RNA-silencing pathways, but the mechanistic roles of Argonaute proteins in these pathways are not clearly understood. To address this question, we performed single-molecule fluorescence experiments using an RNA-induced silencing complex (core-RISC) composed of a small RNA and human Argonaute 2. We found that target binding of core-RISC starts at the seed region of the guide RNA. After target binding, four distinct reactions followed: target cleavage, transient binding, stable binding, and Argonaute unloading. Target cleavage required extensive sequence complementarity and accelerated core-RISC dissociation for recycling. In contrast, the stable binding of core-RISC to target RNAs required seed-match only, suggesting a potential explanation for the seed-match rule of microRNA (miRNA) target selection.

• 한국전기전자재료학회논문지
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• 제18권9호
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• pp.781-786
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• 2005

The binding energy in the n-type $GaAs/Al_xGa_{1-x}As$ quantum well is calculated. The shooting method, modified from the finite difference method, is used for the calculation of the subband energy level and its wave function. In order to account tot the change of the potential energy due to the charged particles, impurities and electrons, the self consistent method is employed. The wave function used for the calculation of the binding energy is assumed to be composed of the envelope function and hydrogenic 1s function. Then, the binding energies calculated by taking into account lot two different types of the hydrogenic 1s function are compared.

• 통합자연과학논문집
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• 제6권3호
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• pp.138-142
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• 2013

The HIV-1 envelope glycoprotein gp120 plays a vital role in the entry of the virus into the host cells. The crucial role of the glycoprotein suggests gp120 as potential drug target for the future antiviral therapies. Identification of the binding mode of small drug like compounds has been an important goal in drug design. In the current study we attempt to propose binding mode of indole derivatives in the binding pocket of gp120. These derivatives are reported to inhibit HIV-1 by acting as attachment inhibitors that bind to gp120 and prevent the gp120-CD4 interaction and thus inhibit the infectivity of HIV-1. To elucidate the molecular basis of the small molecules interactions to inhibit the glycoprotein function we employed the molecular docking simulation approach. This study provides insights to elucidate the binding pattern of indole-based gp120 inhibitors and may help in the rational design of novel HIV-1 inhibitors with improved potency.

• Preventive Nutrition and Food Science
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• 제5권1호
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• pp.1-6
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• 2000

The binding capacity of chitin and chitosan to anthocyanin pigmentss isolated from purple perilla leaves was inves-tigated. The pigment binding capacity increased with increasing pigment concentrations and decreasing pH without being affected by reaction temperature and particle sizes. Regression analysis revealed significantly high corre-lations between pigment binding capacity of chitin and chitosan and pigment concentration at ranges of 25-100 mg of pigment/g of sample, After 1 hr settling, release of pigment from pigmented chitin and chitosan increased with increasing pH, up to 24.9% and 17.4%, respectively, at pH 9. In general, pigment binding capacity of chitosan was higher than that of chitin. There results suggest that chitosan may be useful as a potential adsorbent capable of stabilizing anthocyanin pigment.

• 한국축산식품학회지
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• 제39권4호
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• pp.601-609
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• 2019

Bifidobacterium longum KACC 91563 secretes family 5 extracellular solute-binding protein via extracellular vesicle. In our previous work, it was demonstrated that the protein effectively alleviated food allergy symptoms via mast cell specific apoptosis, and it has revealed a therapeutic potential of this protein in allergy treatment. In the present study, we cloned the gene encoding extracellular solute-binding protein of the strain into the histidine-tagged pET-28a(+) vector and transformed the resulting plasmid into the Escherichia coli strain BL21 (DE3). The histidine-tagged extracellular solute-binding protein expressed in the transformed cells was purified using Ni-NTA affinity column. To enhance the efficiency of the protein purification, three parameters were optimized; the host bacterial strain, the culturing and induction temperature, and the purification protocol. After the process, two liters of transformed culture produced 7.15 mg of the recombinant proteins. This is the first study describing the production of extracellular solute-binding protein of probiotic bacteria. Establishment of large-scale production strategy for the protein will further contribute to the development of functional foods and potential alternative treatments for allergies.

• Journal of Periodontal and Implant Science
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• 제42권5호
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• pp.166-172
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• 2012

Purpose: The aim of this study was to evaluate the improvement of osteogenic potential of biphasic calcium phosphate (BCP) bone substitute coated with synthetic cell-binding peptide sequences in a standardized rabbit sinus model. Methods: Standardized 6-mm diameter defects were created bilaterally on the maxillary sinus of ten male New Zealand white rabbits, receiving BCP bone substitute coated with synthetic cell binding peptide sequences on one side (experimental group) and BCP bone substitute without coating (control group) on the other side. Histologic and histomorphometric analysis of bone formation was carried out after a healing period of 4 or 8 weeks. Results: Histological analysis revealed signs of new bone formation in both experimental groups (4- and 8-week healing groups) with a statistically significant increase in bone formation in the 4-week healing group compared to the control group. However, no statistically significant difference in bone formation was found between the 8-week healing group and the control group. Conclusions: This study found that BCP bone substitute coated with synthetic cell-binding peptide sequences enhanced osteoinductive potential in a standardized rabbit sinus model and its effectiveness was greater in the 4-week healing group than in the 8-week healing group.