• Journal of Animal Science and Technology
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• v.54 no.3
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• pp.191-198
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• 2012

The objective of this study was to evaluate the potential use of a dielectric barrier discharge (DBD) plasma system to improve microbial safety of sliced cheese. The atmospheric pressure plasma (APP) effect on visual appearance and a sensory evaluation were also carried out. The number of Escherichia coli inoculated on cheese slices decreased by 0.09, 0.47, 1.16 and 1.47 log cycles with helium (4 liters/min [lpm]) and 0.05, 0.87, 1.89 and 1.98 log cycles with He/$O_2$ mixture (4 lpm/15 standard cubic centimeters per minute), after being treated with plasma for 1, 5, 10, and 15 min, respectively. Significant reductions were also observed in Staphylococcus aureus inoculated onto cheese slices ranging from 0.05 to 0.45 log cycles with He and from 0.08 to 0.91 log cycles with He/$O_2$-treated samples, respectively. Adding oxygen resulted in a significant increase in inactivation of both pathogens. No visible change in the plasma-treated cheese slices was observed even though the instrumental analysis showed a significant decrease in the $L^*$-value and an increase in the $b^*$-value. The cheese slices were damaged after 10 and 15 min of plasma treatment. In addition, significant reductions in sensory quality including flavor, odor, and acceptability of plasma-treated cheese slices were observed. The results indicate that the DBD plasma system has potential for use in sanitizing food products, although the effect was limited. Further development of the APP system is necessary for industrial use.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.519-523
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• 2017

We investigated the applications of functional materials through the examination of a variety of physiological activities of Ipomoea aquatica extract. I. aquatica extract showed low cytotoxicity against murine melanoma B16F10 cells. At concentrations that exerted little or no cytotoxicity to the cells, I. aquatica extract showed high DPPH radical scavenging activity ($ID_{50}$, $7.84{\mu}g/mL$), inhibited tyrosinase activity ($ID_{50}$, $106.56{\mu}g/mL$), and decreased melanin content ($ID_{50}$, $41.75{\mu}g/mL$). The treatment of B16F10 cells with I. aquatica extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggested that I. aquatica extract inhibited melanin synthesis in murine melanoma B16F10 cells through the suppression of intracellular tyrosinase expression, as well as the simultaneous direct inhibition of tyrosinase activity. Additionally, I. aquatica extract promoted the expression of involucrin, which is related to skin barrier protection. These results indicate that I. aquatica extract may be an appropriate material for the improvement of skin barrier function.

• Journal of the Semiconductor & Display Technology
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• v.15 no.2
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• pp.26-31
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• 2016

The Townsend to glow discharge mode transition was investigated in the dielectric barrier discharge (DBD) helium plasma source which was powered by 20 kHz / $4.5 kV_{rms}$ high voltage at atmospheric pressure. The spatial profile of the electric field strength at each modes was measured by using the intensity ratio method of two helium emission lines (667.8 nm ($3^1D{\rightarrow}2^1P$) and 728.1 nm ($3^1S{\rightarrow}2^1P$)) and the Stark effect. ICCD images were analyzed with consideration for the electric field property. The Townsend discharge (TD) mode at the initial stage of breakdown has the light emission region located in the vicinity of the anode. The electric field of the light emitting region is close to the applied field in the system. Immediately, the light emitting region moves to the cathode and the discharge transits to the glow discharge (GD) mode. This mode transition can be understood with the ionization wave propagation. The electric field of the emitting region of GD near cathode is higher than that of TD near anode because of the cathode fall formation. This observation may apply to designing a DBD process system and to analysis of the process treatment results.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.552-552
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• 2013

In our study we consider Al2O3 ceramic substrates for Plasma Surface Treatments in order to improve deposited diamond surface and increase diamond deposition rate by applying DBD (Dielectric Barrier Dischrge) system. Because Plasma Surface Treatments was used as a modification method of material surface properties like surface free energy, wettability, and adhesion. By applying Plasma Surface Treatments diamond films are deposited on the Al2O3 ceramic substrates. DC Arc Plasmatron with mathane and hydrogen gases is used. Deposited diamond films are investigated by SEM (Scanning Electron Microscopy), AFM (Atomic Force Microscopy) and XRD (X-ray Diffractometer). Then the C-H stretching of synthetic diamond films by FTIR (Fourier Transform Infrared Spectroscopy) is studied. As a result, nanocrystalline diamond films were identified by using SEM and diamond properties in XRD peaks at (111, $43.8{\Box}$, (220, $75.3{\Box}$ and (311, $90.4{\Box}$ were shown. Absorption peaks in FTIR spectrum, caused by CHx sp3 bond stretching of CVD diamond films, were identified as well. Finally, we improved such parameters as depostion rate ($2.3{\mu}m$/h), diamond surface uniformity, and impurities level by applying Plasma Surface Treatments. These experimental results show the importance of Plasma Surface Treatments for diamond deposition by a plasma source.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.65-72
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• 2012

Aluminum induced crystallization of amorphous silicon was attempted by the aluminum substrate. To avoid the layer exchange between silicon and aluminum layer, Ni layer was deposited between these two layers by sputtering. To obtain the bigger grain of the crystalline silicon, wet blasted silica layer was employed as windows between the nickel and a-Si layer. Ni obtained after the annealing treatment at $520^{\circ}C$ was found to be a promising material for the diffusion barrier between silicon and aluminum. One way to obtain bigger grain of crystalline silicon layer applicable to solar cell of higher performance was envisioned in this investigation.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.344-348
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• 2018

We investigated the application of functional materials by examining a variety of physiological activities of Abelmoschus esculentus extract. A. esculentus extract had a low cytotoxicity against murine melanoma B16F10 cells. At concentrations showing little or no cytotoxicity, A. esculentus extract showed high a DPPH radical scavenging activity ($ID_{50}$, $5.24{\mu}g/mL$), inhibited tyrosinase activity ($ID_{50}$, $102.12{\mu}g/mL$), and decreased melanin content ($ID_{50}$, $17.85{\mu}g/mL$). The treatment of B16F10 cells with A. esculentus extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggest that A. esculentus extract inhibits melanin synthesis in murine melanoma B16F10 cells by suppressing intracellular tyrosinase expression, as well as directly inhibits tyrosinase activity simultaneously. Additionally, A. esculentus extract promotes the expression of involucrin, which is related to skin barrier protection. These results indicate that A. esculentus extract is an appropriate material for improving skin barrier function.

• Women's Health Nursing
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• v.16 no.2
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• pp.105-115
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• 2010

Purpose: The purpose of this study was to determine the effects of an environmental enrichment program on barrier, benefit, confidence, and compliance of breast self-examination in women at 3 months after instruction. Methods: Nonequivalent control group pretest-posttest design was conducted among 62 healthy women. Data were collected through the self-reported questionnaires from December 2008 to March 2009. Women were assigned to one of two treatment groups: (a) no-support of environmental enrichment with the instruction control group; (b) the support of environmental enrichment with the instruction experimental group. All women received the same instruction on breast self-examination once a week for two weeks. Data were analyzed with paired t-test, McNemar test and ANCOVAs of controlling for age run using SPSS/WIN 17.0. Results: The experimental group was significantly lower than control group on perceived barrier (F=5.91, p=.02) and higher than control group on compliance of breast self-examination (F=4.57, p=.04) after environmental enrichment program. However the environmental enrichment program did not make significant differences on benefit (F=0.01, p=.91) and confidence (F=0.77, p=.38). Conclusion: Findings suggest that the environmental enrichment should be needed to support women's breast self-examination and expanded for compliance of breast self-examination to promote the secondary prevention of women breast cancer.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.4
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• pp.389-397
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• 2019

Lysosomes are cellular organelles involved in energy metabolism and intracellular digestion in eukaryotic cells, including protease, nuclease, glycosidase, lipase, and phosphatase. Our previous studies have confirmed that egg white lysosomes had melanin decolorization and reduction activity. However, there have been few studies on skin barrier and skin regeneration as well as inhibition of melanin production by egg white lysosomes on B16F10 melanocyte cell line. In this study, we attempted to identify the effect of lysosome-related organelle extract (LOE) extracted from egg white on the melanin content change and skin barrier enhancement in cells. First, cytotoxicity evaluation was performed on B16F10 melanocyte cell line to confirm the whitening efficacy of LOE. Cytotoxicity by LOE was not observed at 20 mg/mL concentration, but cytotoxicity was observed at 40 mg/mL, and the maximum concentration value was set to 20 mg/mL in all subsequent experiments. LOE samples of 5, 10, 20 mg/mL inhibited melanin production by 61.5 ± 4.0%, 61.4 ± 7.3%, 58.3 ± 8.3%, respectivly, compared to α-MSH, a negative control in melanin contents assay. MITF mRNA expression was reduced by about 39.7 ± 3.2% compared to the α-MSH treatment group. TEER assay using HaCaT showed that LOE increased TEER resistance in a dose-dependent manner, indicating that LOE is involved in strengthening the skin barrier. LOE also increased the TEER resistance under TNF-α treatment. Skin barrier was normally restored by LOE even under the condition of inflammation. LOE had a positive effect on cell division and cell migration promotion, confirmed by the observing the effect of promoting cell migration by LOE through cell migration assay. Taken together, we expect that LOE can be developed as a cosmetic material to enhance has effects on skin regeneration and skin barrier strengthening as well as whitening function if enzyme stabilization and formulation technology are combined.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.985-993
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• 2014

For the field application of dielectric barrier discharge plasma reactor, a multi-plasma reactor was investigated for the inactivation of microorganisms in sewage. We also considered the possibility of degradation of non-biodegradable matter ($UV_{254}$) and total organic carbon (TOC) in sewage. The multi-plasma reactor in this study was divided into high voltage neon transformers, gas supply unit and three plasma modules (consist of discharge, ground electrode and quartz dielectric tube). The experimental results showed that the inactivation of microorganisms with treated water type ranked in the following order: distilled water > synthetic sewage effluent >> real sewage effluent. The dissolved various components in the real sewage effluent highly influenced the performance of the inactivation of microorganisms. After continuous plasma treatment for 10 min at 180 V, residual microorganisms appeared below 2 log and $UV_{254}$ absorbance (showing a non-biodegradable substance in water) and TOC removal rate were 27.5% and 8.5%, respectively. Therefore, when the sewage effluent is treated with plasma, it can be expected the inactivation of microorganisms and additional improvement of water quality. It was observed that the $NH_4{^+}$-N and $PO{_4}^{3-}$-P concentrations of sewage was kept at the constant plasma discharging for 30 min. On the other hand, $NO_3{^-}$-N concentration was increased with proceeding of the plasma discharge.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.2
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• pp.152-155
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• 2011

Even though nano-scale materials were very advantageous for various applications, there are still problems to be solved such as the stabilization of surface state and realization of low contact resistances between a semiconducting nanowire and electrodes in nano-electronics. It is well known that the effects of contacts barrier between nano-channel and metal electrodes were dominant in carrier transportation in individual nano-electronics. In this report, it was investigated the electrical properties of GaN nanorod devices after chemical etching and rapid thermal annealing for making good contacts. After KOH wet-etching of the contact area the devices showed better electrical performance compared with non-treated GaN individual devices but still didn't have linear voltage-current characteristics. The shape of voltage-current properties of GaN devices were improved remarkably after rapid thermal annealing as showing Ohmic behaviors with further bigger conductivities. Even though chemical etching of the nanorod surfaces could cause scattering of carriers, in here it was shown that the most important and dominant factor in carrier transport of nano-electronics was realization of low contact barrier between nano-channel and metal electrodes surely.