• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.6
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• pp.256-259
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• 2006

The amorphous $SiO_x$ nanowires were synthesized by the vapor phase epitaxy (VPE) method. $SiO_x$ nanowires were formed on silicon wafer of temperatures ranged from $800{\sim}1100^{\circ}C$ and nickel thin film was used as a catalyst for the growth of nanowires. A vapor-liquid-solid (VLS) mechanism is responsible for the catalyst-assisted amorphous $SiO_x$ nanowires synthesis in this experiment. The SEM images showed cotton-like nanostructure of free standing $SiO_x$ nanowires with the length of more than about $10{\mu}m$. The $SiO_x$ nanowires were confirmed amorphous structure by TEM analysis and EDX spectrum reveals that the nanowires consist of Si and O.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.470-475
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• 2013

Zr-benzendicarboxylate structure, UiO-66 was prepared in 1-L batch scale by using a unique sonochemical-solvothermal combined synthesis method. The produced UiO-66 showed uniform particles of ca. $0.2{\mu}m$ in size with the BET surface area of $1,375m^2/g$ in high product yield (>95%). The UiO-66 showed 198 and 84 mg/g $CO_2$ adsorption capacity at 273 K and 298 K, respectively, with excellent $CO_2$ selectivity ($CO_2:N_2=32:1$) at ambient conditions. The isosteric heat of $CO_2$ adsorption varied from 33 to 25 kJ/mol as the adsorption progressed. The UiO-66 tested for xylene isomer separation in a liquid-phase batch mode confirmed preferential adsorption of the adsorbent for o-xylene over m-, and p-xylene.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.27 no.1
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• pp.58-67
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• 2014

Objective : Lycii Fructus Extracts(LFE) can do Anti-hypertension activity, Antidepressant, Anti-diabetic activity. This study was designed to investigate effects of LFE on skin whitening and elasticity using melanoma cells. Methods : In this experiment, effect of LFE on cell viability, inhibition of melanin synthesis and inhibitory effect on tyrosinase and elastase. Results : More than $250{\mu}g/ml$ of LFE treated group showed lowered proliferation rates significantly compared to non-treated group. More than $125{\mu}g/ml$ of LFE treated groups were lower levels of melanin synthesis respectively. LFE showed inhibitory effect on tyrosinase activities in vitro. And, LFE suppressed tyrosinase activities in B16F10 cells significantly. Finally, LFE suppressed elastase type I and IV activities in dose-dependent manner in vitro. And LFE also slightly suppressed elastase activities in vivo. Conclusion : These results suggest that LFE can inhibit melanin synthesis through ihhibitory action on tyrosinase activity and inhibt elastase activity, and also suggest that these results can be used for the study on maintaining skin elasticity or whitening.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.105-109
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• 2007

This study was carried out to investigate the biological effects oak wood vinegar. Antimicrobial activity was tested in five microbial species at the concentration of 5 to $50{\mu}l$ of oak wood vinegar by paper disc method. Growth of P. oleovoranse, P. vulgaris, E. coli, S. aureus and Prevotella intermedia was inhibited at a dose of as low as $50{\mu}l$ of oak wood vinegar. Antioxidant activities were measured by using DPPH radical scavenging and SOD-like activity. DPPH radical scavenging and SOD-like activities were 90% and 65% at the concentration of $25{\mu}l\;and\;50{\mu}l$ of oak wood vinegar, respectively. Stimulation of the macrophages RAW264.7 cells with lipopolysaccharide (LPS) resulted in increased production of nitric oxide (NO) in the medium. However, the oak wood vinegar showed marked inhibition of NO synthesis in a dose-dependent manner. This result suggest that oak wood vinegar plays significant role for activation of immune system in the pathogenesis of inflammatory diseases.

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.4
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• pp.317-325
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• 2011

In this paper a robust voltage controller for a single-phase UPS inverter is newly presented. The voltage controller is designed using ${\mu}$-based robust control scheme to simultaneously guarantee robust stability and robust tracking performance in the presence of load variations. Firstly the robust performance of the resulting controller is theoretically confirmed via ${\mu}$-analysis. Then simulations and experiments for the single-phase inverter system with linear and nonlinear loads demonstrate feasibility of the proposed control method providing improved performance - good regulation and fast dynamic response.

• Journal of Dairy Science and Biotechnology
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• v.37 no.2
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• pp.136-153
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• 2019

The present study aimed to investigate the effects of skin care foods on the synthesis of pro-collagen type I C peptide and suppression of matrix metalloproteinase (MMP)-1 secretion through an in vitro study using fibroblasts (Hs68 cells) and keratinocytes (HaCaT cells). Among the three skin care foods developed in this study, three beans cookie and avocado yoghurt influenced the production of pro-collagen type I C peptide and suppressed MMP-1 secretion; however, tiger nut Galsu drink did not exhibit these effects. All skin care foods, including three beans cookie and plain yoghurt ($50{\mu}g/mL$, p<0.001) influenced the suppression of MMP-1 in addition to other commercially available breast milk production support foods examined, such as Heath Heather ($50{\mu}g/mL$, p<0.001), Happy Mama ($50{\mu}g/mL$, p<0.01), BioLys ($50{\mu}g/mL$, p<0.001), Enfamama ($25{\mu}g/mL$, p<0.0001), and Pregnagen ($25{\mu}g/mL$, p<0.001). Avocado fruit yoghurt ($25{\mu}g/mL$, p<0.05), avocado fruit jam yoghurt ($50{\mu}g/mL$, p<0.01), Enfamama ($100{\mu}g/mL$, p<0.05), and Pregnagen ($100{\mu}g/mL$, p<0.05) influenced the production of pro-collagen type I C peptide and suppressed MMP-1 secretion. This result indicates that only avocado jam yoghurt significantly influenced both the prevention of skin keratinization and acceleration of recovery of skin fibrous structure. Therefore, avocado is a favorable ingredient for nutrition-balanced dietary foods or an essential ingredient in products for revitalization of human skin.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.414-421
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• 2014

This study was conducted to determine the effects of saturated long-chain fatty acids (LCFA) on cell proliferation and triacylglycerol (TAG) content, as well as mRNA expression of ${\alpha}s1$-casein (CSN1S1) and genes associated with lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows, and were passaged twice. Then cells were cultured with different levels of palmitate or stearate (0, 200, 300, 400, 500, and 600 ${\mu}M$) for 48 h and fetal bovine serum in the culture solution was replaced with fatty acid-free BSA (1 g/L). The results showed that cell proliferation tended to be increased quadratically with increasing addition of stearate. Treatments with palmitate or stearate induced an increase in TAG contents at 0 to 600 ${\mu}M$ in a concentration-dependent manner, and the addition of 600 ${\mu}M$ was less effective in improving TAG accumulation. The expression of acetyl-coenzyme A carboxylase alpha, fatty acid synthase and fatty acid-binding protein 3 was inhibited when palmitate or stearate were added in culture medium, whereas cluster of differentiation 36 and CSN1S1 mRNA abundance was increased in a concentration-dependent manner. The mRNA expressions of peroxisome proliferator-activated receptor gamma, mammalian target of rapamycin and signal transducer and activator of transcription 5 with palmitate or stearate had no significant differences relative to the control. These results implied that certain concentrations of saturated LCFA could stimulate cell proliferation and the accumulation of TAG, whereas a reduction may occur with the addition of an overdose of saturated LCFA. Saturated LCFA could up-regulate CSN1S1 mRNA abundance, but further studies are necessary to elucidate the mechanism for regulating milk fat and protein synthesis.

• Restorative Dentistry and Endodontics
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• v.20 no.1
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• pp.275-288
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• 1995

The inhibitory effect of cell wall extracts of streptococci, have been investigated to know host-parasite relationship or pathogenesis of abscess formation. Streptococci isolated from the infected root canals were sonicated to get cell wall extracts which have been known as one of the factors of pyogenesis. Lymphocytes separated by density gradient were stimulated with phytohemagglutinin and exposed to cell wall extracts of Streptococcus sanguis, S. mitis, S. uberis, S. mutans (ATCC 10449), and S. faecalis (ATCC 19433). [$^3H$]-thymidine uptake of lymphocytes was analyzed with scintillation counter and lactate dehyrogenase (LD) activity was measured with autochemistry analyzer. S. faeealis had the strongest inhibitory effect. beginning at $100\;{\mu}g/ml$ concentration of sonic extracts. S. sanguis and S. mitis had inhibitory effect at $300\;{\mu}g/ml$, while S. uberis and S. mutans showed no inhibitory, effect on DNA syntheis even at $300\;{\mu}g/ml$. Each streptococci showed different inhibitory effect on the DNA synthesis of lymphocytes, which finding indicated wide spectrum of susceptibility of lymphocytes according to streptococcus spp. There were no significant difference of LD activities between control and each streptococcal extracts. Streptococcal sonic extracts did not affect the morphological findings or number of colonies activated lymphocytes. These finding suggested the inhibitory effect of sonic extract of streptococci to lymphocytes could be detected by DNA synthesis inhibition, not by cellular membrane damage.

• Animal cells and systems
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• v.2 no.3
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• pp.383-388
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• 1998

A RecA-like protein (RecAps) was identified from fluorescent Pseudomonas sp. and the inducible nature of the protein was characterized in detail. It was shown by dose-response and time-course experiments using two DNA damaging agents, nalidixic acid and mitomycin-C, that the cellular level of RecAps protein was increased 3-8 fold compared to that of the control. The most effective doses of nalidixic acid and mitomycin-C for the protein induction were $30{\mu}g/ml$ and $0.3{\mu}g/ml$ at the treatment time point of 150 min, respectively. The enhanced level of RecAps protein was gradually decreased to the control level after 10 hr in normal medium. Interestingly, the cellular level of RecAps protein was increased by the same DNA damaging agents even when cell growth was completely inhibited by treatment with $170{\mu}g/ml$ of chloramphenicol, an inhibitor of protein synthesis, suggesting that new protein synthesis is not required for the induction of RecAps. All these results suggest that a typical S0S repair function driven by RecA-like protein is conserved in Pseudomonas sp. cells as in E, coli.

• Korean Journal of Plant Resources
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• v.30 no.3
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• pp.272-279
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• 2017

EP was obtained through 20% ethanol extraction of Pueraria lobata root, and the fermented form of EP, FEP, was prepared from the EP after incubating with Lactobacillus rhamnosus vitaP1. There was no significant toxicity by EP and FEP up to $1000{\mu}g/ml$ in NIH-3T3, HaCaT, and B16F10 cells. In addition to antioxidant potentials of EP and FEP determined by DPPH and ABST assays, we confirmed increase of procollagen type I and elastin synthesis by supplementation of the EP and FEP at the concentration of $50{\mu}g/ml$ using ELISA kits. The protein expression levels of matrix metalloprotease (MMP)-1, -3, and -9, those are involved in the degradation of collagen or other skin matrix proteins, were remarkably suppressed while their inhibitory protein metallopeptidase inhibitor 1 (TIMP-1) was greatly up-regulated by supplementation of the EP and FEP at a concentration of $50{\mu}g/ml$. Taken together, both EP and FEP supplementation could be involved in the suppression of the skin wrinkle formation through inhibiting degradation of collagen and stimulating the synthesis of collagen and elastin. The results showed that the anti-wrinkle potential of the EP and FEP will be a promising candidate for developing cosmeceutical compounds or products.