• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.274-278
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• 2008

Hard coating solutions were prepared from glycidoxypropyl trimethoxysilane (GPTMS) and methacryloxypropyl trimethoxysilane (MPTMS) precursors with different molar ratios of 10:0, 9:1, 7:3, 5:5, 3:7, and 0:10, respectively, by the sol-gel method. The polycarbonate (PC) sheets were spin-coated, and cured at $130^{\circ}C$ for 3 h. The effect of the GPTMS:MPTMS molar ratios of the mixture was investigated on the properties of coating films. The highest pencil hardness and adhesion to PC sheets of coating films were found for solution with GPTMS:MPTMS molar ratio of 5:5. Also, the pencil hardness of coating films was increased with increasing the $H_2O$ content in the coating solutions.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.162-169
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• 2013

We determined the optimum pretreatment conditions such as pH and time for swelling duck feet and investigated the effects of the extracting method, such as water bath (WB), pressure cooker (PC), and microwave oven (MO), on quality characteristics of the duck feet gelatin for improving utilization of duck feet as a novel source of gelatin. The soaking solution of pH 1 among pH 1-14 with unit intervals was selected due to the highest yield. The quality characteristics of the gelatin tested were color, pH, gel strength, viscosity, and melting point. For the extracted gelatin with different methods, the CIE $L^*$, $a^*$ and $b^*$ values were in the following order: MO>PC>WB (p<0.05), WB>PC>MO (p<0.05) and PC>MO>WB (p<0.05), respectively. The gelatin extracted using WB showed the highest pH and that extracted using MO showed the lowest pH (p<0.05). The gel strength, viscosity, and melting point were the highest for MO (p<0.05). The gel strength and melting point were the lowest for PC (p<0.05). No significant difference was found in viscosity between the gelatins extracted using WB and PC (p>0.05). The quality characteristic of duck feet gelatin was affected by extracting methods, and MO extraction can be one of the effective methods for duck feet gelatin.

• Journal of the Korean Vacuum Society
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• v.18 no.2
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• pp.85-91
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• 2009

There has been a rapid progress for flexible polymer-based MEMS(Microelectromechanical Systems) technology. Polycarbonate (PC) and Poly Methyl Methacrylate (PMMA), so-called acrylic, have many advantages for optical, non-toxic and micro-device application. We studied dry etching of PC and PMMA as a function of % gas ratio in the $O_2/SF_6/CH_4$ temary plasma. A photoresist pattern was defined on the polymer samples with a mask using a conventional lithography. Plasma etching was done at 100 W RIE chuck power and 10 sccm total gas flow rate. The etch rates of PMMA were typically 2 times higher than those of PC in the whole experimental range. The result would be related to higher melting point of PC compared to that of PMMA. The highest etch rates of PMMA and PC were found in the $O_2/SF_6$ discharges among $O_2/SF_6$, $O_2/CH_4$ and $SF_6/CH_4$ and $O_2/SF_6/CH_4$ plasma composition (PC: ${\sim}350\;nm/min$ at 5 sccm $O_2/5$ sccm $SF_6$, PMMA: ${\sim}570\;nm/min$ at 2.5 sccm $O_2/7.5$ sccm $SF_6$). PC has smoother surface morphology than PMMA after etching in the $O_2/SF_6/CH_4$ discharges. The surface roughness of PC was in the range of 1.9$\sim$3.88 nm. However, that of PMMA was 17.3$\sim$26.1 nm.

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.163-170
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• 1993

The effect of substrate micellization on the hydrolysis rate in the production of lysopho-sphatidylcholine (LPC) from phosphatidylcholine (PC) using hog pancreas phospholipase A2(PLA2) was studied. The optimal temperature and pH for the reactions in aqueous phase was found 42C and 7.2, respectively. For a given PC concentration, initial reaction rate was progressively increased with the addition of sodium deoxycholate (DOC), which could transform the bilayer of phospholipids into micellar structure.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5905-5910
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• 2013

Background: To investigate the preventive and therapeutic potential of garlic oil on human pancreatic carcinoma cells. Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was performed to study the effects of garlic oil on three human pancreatic cancer cell lines, AsPC-1, Mia PaCa-2 and PANC-1. Cell cycle progression and apoptosis were detected by flow cytometry (FCM), staining with PI and annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI), respectively. Morphologic changes of pancreatic cancer cells were observed under transmission electron microscopy (TEM) after treatment with garlic oil at low inhibitory concentrations ($2.5{\mu}M$ and $10{\mu}M$) for 24 hours. Results: Proliferation of the AsPC-1, PANC-1, and Mia PaCa-2 cells was obviously inhibited in the first 24 hours with the MTT assay. The inhibition effect was more significant after 48 hours. When cells were exposed to garlic oil at higher concentrations, an early change of the apoptotic tendency was detected by FCM and TEM. Conclusion: Garlic oil could inhibit the proliferation of AsPC-1, PANC-1, and Mia PaCa-2 cells in this study. Moreover, due to programmed cell death, cell cycle arrest, or both, pro-apoptosis effects on AsPC-1 cells were induced by garlic oil in a dose and time dependent manner in vitro.

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.605-612
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• 2020

In this study, 11 plant extracts from Bangladesh were used to evaluate the total phenolic and flavonoid content, in vitro antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis-(3-ethylbenzthiazolin-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assay. Also, the inhibitory effect of nitric oxide (NO) production in RAW 264.7 macrophage cell line and the neuroprotective effect on H2O2-induced PC12 cells were tested. Our results revealed that Piper betle L. showed the highest total phenolic content (162.2 mg GAE/g extract) among the 11 plants from Bangladesh. Most plants showed strong radical scavenging effects and ferric reducing antioxidant power. Besides, Piper betle L. protected PC12 neuronal cells against H2O2 related oxidative stress in LPS-induced PC12 cells. Regarding the anti-inflammatory effect, Piper betle L. significantly inhibited NO accumulation in LPS-induced RAW 264.7 cells. Our results provide evidence that Piper betle L. could be useful for the development of functional health foods.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.858-862
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• 2007

The present study was conducted to examine the antioxidant activities and neuroprotective effects of methanolic extracts from Schizonepeta tenuifolia Briquet (STE). STE ($100\;{\mu}g/mL$) showed $43.33\;{\mu}M$ of total phenolic content, 64.43% of radical scavenging activity, and 0.157 of reducing power. In addition, the effect of STE on $H_2O_2$-induced DNA damage in human leucocytes was evaluated by the comet assay, where STE was a dose dependent inhibitor of DNA damage induced by $200{\mu}M$ of $H_2O_2$. The protective effect of STE against $H_2O_2$-induced oxidative damage on PC12 cells was investigated by an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and lactate dehydrogenase (LDH) release assays. After 2 hr of cell exposure to $H_2O_2\;(500\;{\mu}M)$, a marked reduction in cell survival was observed. However, this reduction was significantly prevented by $1-50\;{\mu}g/mL$ of STE. Therefore, these results suggest that STE could be a new antioxidant candidate against neuronal diseases.

• YAKHAK HOEJI
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• v.50 no.2
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• pp.105-110
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• 2006

The effects of tributyltin acetate (TBTA), one of the endocrine-disrupting organotin compounds, on dopamine biosynthesis in PC12 cells were investigated. Treatment of PC12 cells with TBTA at $0.05\sim0.25{\mu}M$ significantly decreased the intracellular dopamine content in a concentration-dependent manner ($IC_{50}$ value, $0.17{\mu}M$). Under these conditions, tyrosine hydroxylase (TH) activity and TH mRNA level were also decreased by $0.1{\mu}M$ TBTA at 24 h, and recovered there-after. In addition, treatment with L-DOPA at 20 and $50 {\mu}M$ increased the intracellular dopamine content in PC12 cells and the increase in dopamine content by L-DOPA was significantly abolished by TBTA at $0.1\sim0.2{\mu}M$. These results indicate that TBTA at $0.1\sim0.2{\mu}M$ causes the decrease in the basal dopamine content and abolishes the increase in dopamine content in L-DOPA-treated cells in part by the inhibition of TH gene expression and activity.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.58.1-58.1
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• 2013

We present $10{\mu}m-35{\mu}m$ Spitzer spectra of the interstellar medium in the Central Molecular Zone (CMZ), the central 210 pc ${\times}$ 60 pc of the Galactic center (GC). We present maps of the CMZ in ionic and $H_2$ emission, covering a more extensive area than earlier spectroscopic surveys in this region. The radial velocities and intensities of ionic lines and $H_2$ suggest that most of the $H_2$ 0-0 S(0) emission comes from gas along the line-of-sight, as found by previous work. We compare diagnostic line ratios measured in the Spitzer Infrared Nearby Galaxies Survey (SINGS) to our data. Previous work shows that forbidden line ratios can distinguish star-forming galaxies from LINERs and AGNs. Our GC line ratios agree with star-forming galaxies and not with LINERs or AGNs.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.257-261
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• 2013

Rat pheochromocytoma cells (PC12) and mice were utilized as in vitro and in vivo models to determine the neuroprotective effects of a 70% acetone extract of black soybean seed coat (BSSCE). BSSCE showed higher total phenolic contents than other extracts. Intracellular reactive oxygen species accumulation from $H_2O_2$ treatment of PC12 cells was significantly reduced when BSSCE was present in the media compared to PC12 cells treated with $H_2O_2$ only. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromide (MTT) reduction assay and lactate dehydrogenase assay also showed significantly increased protective effects in PC12 cells. In addition, BSSCE improved the in vivo cognitive ability against amyloid beta peptide-induced neuronal deficits.