• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.274-279
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• 2007

This study focuses on the enhancement of maskless photolithography as well as the peptide synthesis application with single crystalline silicon micromirrors. A single crystalline silicon micromirror array has been designed and fabricated in order to improve its application to the peptide synthesis. A micromirror rotates about ${\pm}\;9^{\circ}$ at the pull-in voltage, which can range from 90.7 V to 115.1 V. A $210\;{\mu}m-by-210\;{\mu}m$ micromirror device with $270\;{\mu}m$ mirror pitch meets the requirements of an adequately precise separation for peptide synthesis. Synthetic 16 by 16 peptide array corresponds to the same number of micromirrors. The large size of peptide pattern and the separation facilitate biochip experiments using fluorescence assay. The peptide pattern has been synthesized on the GPTS-PEG200 surface with BSA-blocking and thereupon the background was acetylated to reject non-specific bindings. Hence, an averaged slope at the pattern edge has been distinguishably improved in comparison to patterning results from an aluminum micromirror.

• Journal of the Korean Ceramic Society
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• v.32 no.8
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• pp.893-900
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• 1995

The porous wollastonite ceramics were fabricated after firing calcium silicates, obtained using natural resources and by-products of power plants by hydrothermal synthesis, without organic fibers or asbestos for reinforcement agent. A specimen from diatomite as a SiO2 staring raw material had the highest strength owing to normal grain growth and good densification from homogeneous sperhcial C-S-H hydrates. A specimen from SiO2 sol as a SiO2 starting raw material showed tobermolite, but fly ash and mixed system did xonotlite after hydrothermal synthesis. The specimen from fly ash showed the lowest firing shirikage and strength changes in the firing range from 50$0^{\circ}C$ to 120$0^{\circ}C$. The other phases in all specimens changed to wollastonite phase after firing at 100$0^{\circ}C$. Also the average pore size was distributed from 0.2${\mu}{\textrm}{m}$ to 2${\mu}{\textrm}{m}$.

• Korean Journal of Pharmacognosy
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• v.34 no.3 s.134
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• pp.237-241
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• 2003

This study was carried out to test the growth inhibitory effects of sesamolin obtained from sesame seeds. Sesamolin inhibited the growth of human leukemia HL-60 cells in cultures and the synthesis of macromolecules in dose- and time-dependent manners. Sesamolin in the $60{\sims}100\;{\mu}g/ml$ range was cytostatic. At concentrations greater than $200\;{\mu}g/ml$ sesamolin was cytocidal to HL-60 cells and at $60\;{\mu}g/ml$ inhibited the synthesis of DNA, RNA and protein in HL-60 cells by 35.1, 6.1, and 5.3%, whereas at $200\;{\mu}g/ml$ these inhibitions were 86.8%, 81.5% and 96.7%, respectively. The inhibitory effect of sesamolin on DNA synthesis was irreversible.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1386-1391
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• 2017

The bioactivities of boxthron fruits, a source of oriental medicine, are well known, whereas phytochemical studies of the boxthorn stem are rare. In this study, the stem extract of boxthorn (Lycium chinense Miller) and its subfractions were evaluated for their effects on nitric oxide (NO) inhibition and procollagen type I peptide (PIP) synthesis. A phenolic amide isolated from the stem extract was also assayed for these effects. The compound, N-trans-feruloyltyramine, was identified by $^1H$, $^{13}C$, and 2D-nuclear magnetic resonance analyses. In NO inhibition, the chloroform fraction (CF) exhibited the strongest inhibitory activity ($MIC_{50}=24.69{\mu}g/ml$) among the subfractions of the ethanol extract (EE). N-trans-feruloyltyramine isolated from the CF showed strong NO inhibitory activity, presenting with an $MIC_{50}$ of $31.36{\mu}g/ml$. The EE, CF, and N-trans-feruloyltyramine shown to have NO inhibition activity were assayed for the activity of PIP synthesis. The EE and CF showed relatively high PIP values of 38.8% and 24.21% at $100{\mu}g/ml$, respectively. The PIP value for $20{\mu}g/ml$ N-trans-feruloyltyramine showed a 36% increase compared with the non-treated control, whereas that treated with $20{\mu}g/ml$ ascorbic acid as a positive control showed a 13% increase. The results suggest that the proper stem extract of boxthorn stem could be efficiently used to produce good cosmetic effects.

• The Korean Journal of Zoology
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• v.20 no.1
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• pp.41-48
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• 1977

Dose response of DNA repair synthesis induced by bleomycin was dose-dependent in lower doses, and maximum rate of it at 5 $\\mu$g/ml represents about 15% of total cells analyzed. At higher doses DNA-repair synthesis was reduced and the rate of it remained unchanged even prolonged treatment. Pretreatment with BUdR or IUdR was found to enhance DNA repair synthesis and also to interfere with semiconservative DNA synthesis at higher doses. Time dependence study showed that DNA repair synthesis occurred as long as for 24 hours after removal of bleomycin. These results seem to suggest that bleomycin is not to be an effective chemical in inducing excision repair and that damages induced in DNA by this drug might include not only strand breaks but other types of DNA damage.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.57-63
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• 1999

Pericarpium castaneae extracts have variously potent activities, such as anti-oxidative activity and free radical scavenging activity. in vivo and in vitro studies both indicate that pericarpium castaneae extracts acts as a free radical scavenger($IC_{50}:7.6{\mu}g/ml$) stronger than gallic acid($IC_{50}:12.5{\mu}g/ml$) and ellagic acid($IC_{50}:15{\mu}g/ml$) which could prevent cutaneous UV damages and skin aging. The extracts showed a good effect as a anti-oxidant($IC_{50}:50{\mu}g/ml$). It was shown that the appearance of wrinkle in human skin was reduced by topical application of pericarpium castaneae extracts. And the treatment of human skin with the extracts increased the elasticity and moisture of the skin. We investigated the effect of the pericarpium castaneae extracts on production of extracellular matrix using cultured A431 fibroblast cells. The results indicated that the extracts had no detectable effect on collagen synthesis. But synthesis of cell adhesion protein was increased by the extracts. The results suggest that increase of cell adhesion protein synthesis by pericarpium castaneae extracts has closely related to reduction of wrinkle in skin.

• Proceedings of the SCSK Conference
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• 1999.10a
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• pp.57-64
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• 1999

Pericarpium castaneae extracts have variously potent activities, such as anti-oxidative activity and free radical scavenging activity. in vivo and in vivo studies both indicate that pericarpium castaneae extracts acts as a flee radical scavenger ($IC_{50}$/: 7.6$\mu\textrm{g}$/ml) stronger than gallic acid($IC_{50}$/: 12.5$\mu\textrm{g}$/ml) and ellagic acid($IC_{50}$/: 15$\mu\textrm{g}$/ml) which could prevent cutaneous UV damages and skin aging. The extracts showed a good effect as a anti-oxidant ($IC_{50}$/: 50$\mu\textrm{g}$/ml). It was shown that the appearance of wrinkle in human skin was reduced by topical application of pericarpium castaneae extracts. And the treatment of human skin with the extracts increased the elasticity and moisture of the skin. We investigated the effect of tile pericarpium castaneae extracts on production of extracellular matrix using cultured A431 fibroblast cells. The results indicated that the extracts had no detectable effect on collagen synthesis, But synthesis of cell adhesion protein was increased by the extracts. The results suggest that increase of cell adhesion protein synthesis by pericarpium castaneae extracts has closely related to reduction of wrinkle in skin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.33-38
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• 2004

Melanin pigmentation in human skin is a major defense mechanism against ultraviolet light of the sun, but abnormal pigmentation such as freckles, liver spot could be a serious aesthetic problem. Nearly all studies are mainly concentrated on searching for the materials that have inhibitory activities on tyrosinase. In this work, to isolate phenolic compounds from Gastrodia elata, we purified the extract through solvent fractionation, column chromatography, and recrystallization. They were identified as 4-hydroxybenzyl alcohol 1, bis(4-hydroxyphenyl)methane 2, gastrodin (4-${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 on the base of spectroscopic evidences. In order to investigate their depigmentation effect, inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in B16 melanoma cells were evaluated in vitro. We have found that 4-hydroxybenzyl alcohol 1 and gastrodin (4- ${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 have no tyrosinase inhibitory activity, but inhibit the melanin synthesis in B16 melanoma cells. Tyrosinase inhibitory activities of bis(4-hydroxyphenyl)methane 2 (IC$\_$50/ = 400 $\mu\textrm{g}$/mL) and butanol fraction (IC$\_$50/ = 46 $\mu\textrm{g}$/mL) were lower/higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL), but inhibitory activities of melanin synthesis in B16 melanoma cells were much higher than that of arbutin. Especially, tyrosinase inhibitory activities of isolated phenolic fraction (IC$\_$50/ = 2.37 $\mu\textrm{g}$/mL) from butanol fraction was very higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL). Therefore, these results suggest that isolated phenolic compounds from Gastrodia elata have inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in 816 melanoma cells in vitro.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.936-940
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• 2004

Doenjang (Korean soy paste) is one of the popular soybean based fermented foods in Korea. This study investigated the growth and DNA synthesis inhibitory effect of doenjang methanol extracts on AGS human gastric adenocarcinoma cells, Hep 3B human hepatocellular carcinoma cells and HT-29 human colon cancer cells. In order to determine an anticancer effect of doenjang methanol extracts, other soybean fermented foods and original materials were compared. The treatment of doenjang methanol extracts (200 $\mu\textrm{g}$/mL) to the AGS, Hep 3B and HT-29 cancer cells inhibited the growth of cancer cells by 80%, 77% and 86%, respectively. Compared to other soybean fermented foods and original materials, doenjang methanol extracts showed the highest growth inhibitory effect on different cancer cells. In addition, doenjang methanol extracts (200 $\mu\textrm{g}$/mL) significantly inhibited DNA synthesis of AGS and Hep 3B cancer cells by 76% and 59%, respectively. These results suggested that this anticancer effect of doenjang may be due to specific active compounds, which will be newly produced during soybean fermented process and not contained in soybean.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5A
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• pp.849-859
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• 2006

This paper presents an extensive robust analysis of a ${\mu}$-controller in the hybrid system for various uncertainties using the benchmark cable-stayed bridge. The overall system robustness may be deteriorated by introducing active devices and the active controller may cause instability due to small margins. Therefore, a ${\mu}$-synthesis method that simultaneously guarantees the performance and stability of the closed-loop system (robust performance) with uncertainties is used for active devices to enhance the robustness in company with the inherent reliability of passive devices. The robustness of the ${\mu}$-synthesis method is investigated with respect to the additional mass on the deck, structural stiffness matrix perturbation, time delay of actuator, and combinations thereof. Numerical simulation results show that the proposed control system has the good robustness without loss of control performances with respect to various uncertainties under earthquakes considered in this study. Furthermore, the control system robustness is more affected by the perturbation of structural stiffness matrix than others considered in this study. Therefore, the hybrid system controlled by a ${\mu}$-synthesis method could be proposed as an improved control strategy for a seismically excited cable-stayed bridge containing many uncertainties.