• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.4
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• pp.429-437
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• 2010

The aim of this study was to evaluate the fluoride release and microhardness of Beautifil II as giomer(Group I), F2000 Compomer as compomer(Group II), GC Fuji II LC Capsule as resin-modified glass ionomer(Group III) and $Filtek^{TM}$ Z350 as composite resin(Group IV) according to time. Forty discs(5 mm diameter and 2 mm height) were prepared for each material. Each disc was immersed in 3 ml of de-ionized water within polyethylene tube and stored at $37^{\circ}C$. Evaluations were performed by pH/ISE meter for analysis of fluoride release and hardness testing machine for analysis of microhardness over 31 days. The results can be summarized as follows : 1. For all groups except group IV, the greatest fluoride release was observed after the first day of the study period and then dramatically diminished over time. On the 7th day of the study period, fluoride release level was stabilized. 2. Group III showed the highest fluoride release among test groups and then group II, group I were followed. Significant difference in cumulative fluoride release over 31 days was found between each groups. Group IV showed no fluoride release during study period. 3. Group IV showed the highest microhardness among test groups and then group I, group II, group III were followed. Significant difference in microhardness was found between each group, except between group I and group II. 4. After 31 days, microhardness was slightly diminished in every group. However, no significant difference was found.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1522-1528
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• 2004

Electron spin resonance (ESR) and hydrocarbon characteristics were analyzed to establish identification conditions for irradiated dried red pepper. The ESR spectroscopy for 4 different parts (powder, pericarp, seed, stem) of the samples showed that irradiated samples signaled (g=2.024, 2.006, 1.987) a pair of peaks from a cellulose radical at intervals of 6 mT, which were not found on the non-irradiated samples. The ESR signals increased in directly proportion to the irradiation doses, which were still detectable after 12 weeks of storage at room temperature. The GC-MS analysis of hydrocarbons after fat extraction and separation by florisil column chromatography revealed that hydrocarbons, such as 1-tetradecene (14:1), 1,7,10-hexadecatriene (16:3), 1,7-hexadecadiene (16:2), 1-hexadecene (16:1), 6,9-heptadecadiene (17:2), and 8-heptadecene (17:1), were detected only from the irradiated samples immediately after irradiation and 8 months of storage. They linearly increased with the dose of irradiation, suggesting them as radiation-induced markers for irradiated dried red pepper.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.488-498
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• 2017

The aim of this study was to identify volatile and agardiffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.512-521
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• 2016

A bacterial strain was isolated from a soil sample collected on Jeju Island, Korea. The strain, designated WJ-2, exhibited a high xylanase activity, whereas cellulase activity was not detected. The 16S rRNA gene sequence of WJ-2 was highly similar to type strains of the genus Streptomyces. A neighbor-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain WJ-2 is phylogenetically related to Streptomyces atrovirens. Furthermore, DNA-DNA hybridization analysis confirmed that strain WJ-2 is a novel subspecies of Streptomyces atrovirens. The genomic DNA G+C content was 73.98 mol% and the major fatty acid present was anteiso-C15:0 (36.19%). The growth and xylanase production of strain WJ-2 were significantly enhanced by using soytone and xylan as nitrogen and carbon sources, respectively. Crude enzyme preparations from the culture broth of strain WJ-2 exhibited maximal total xylanase activities at pH 7.0 and $55^{\circ}C$. Thin-layer chromatography analysis revealed that the crude enzyme degrades beechwood xylan to yield xylobiose and xylotriose as the principal hydrolyzed end products.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.1
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• pp.47-51
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• 2016

Propionic acidemia (PA) is an autosomal recessively inherited disorder of the organic acid metabolism. It is caused by a deficiency of propionyl-CoA carboxylase (PCC). PCC is a heteropolymeric enzyme composed of ${\alpha}$- and ${\beta}$-subunits. The clinical symptoms of PA are heterogeneous and present vomiting, dehydration, hypotonia, and lethargy, and it can result in death. The typical presentations of neonatal onset PA are life-threatening metabolic acidosis and hyperammonemia. Here, we described a case of neonatal onset PA with mild clinical presentations. She was born to a healthy mother without complications. No significant illness was observed until nine days after birth. She started exhibiting poor oral feeding, vomiting, lethargy, and hypotonia at ten days old. Her laboratory results showed mild hyperammonemia and acidosis. The initial diagnosis was neonatal sepsis and she was treated with antibiotics. However, her clinical symptoms didn't improve. So we considered a metabolic disease. She was given nothing by mouth and intravenous hydration and nutrition support was performed. Propionylglycine and 3-hydroxypropionic acid were showed high concentrations in urine by gas chromatograph mass spectrometry (GC-MS). C3 level of acylcarnitine analysis elevated 10.4 uM/L (range, 0.200-5.00) in plasma. We took gene analysis for PA to be based on the symptoms and laboratory results. We detected PCCB gene mutation and diagnosed PA. She survived without severe neurologic defects and complications and was hospitalized only three times with upper respiratory tract infections for 7 years. We report a case of a ten days old neonate with PA presenting without severe metabolic acidosis and hyperammonemia who was effectively treated with early aggressive care and conventional methods.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.6
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• pp.601-609
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• 2017

Hydrogen is a clean, endlessly produced energy and it is easy to store and transfer. So, hydrogen is regarded as next generation energy. Among various ways for hydrogen production, the way to produce hydrogen by water electrolysis can effectively respond to fossil fuel's depletion or climate change. As interest in hydrogen has increased, related research has been actively conducted in many countries. In this study, we analyzed the performance characteristics and safety of water electrolysis system. In this study, we analyzed the performance characteristics and safety of water electrolysis system. The items for safety performance evaluation of the water electrolysis system were derived through analysis of international regulations, codes, and standards on hydrogen. Also, a prototype of the overall safety performance evaluation station was designed and developed. The demonstration test was performed with a prototype $10Nm^3/h$ class water electrolysis system that operated stably under various pressure conditions while measuring the stack and system efficiency. At 0.7MPa, the efficiency of the alkaline water electrolysis stack and the system that used in this study was 76.3% and 49.8% respectively. Through the GC analysis in produced $H_2$, the $N_2$ (5,157ppm) and $O_2$ (1,646 ppm) among Ar, $O_2$, $N_2$, CO and $CO_2$ confirmed as main impurities. It can be possible that the result of this study can apply to establish the safety standards for the hydrogen production system by water electrolysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.795-800
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• 2003

Juniper seed oil extracted by steam distillation has been a useful material as a medicine, insect repellant, and flavorant for alcoholic beverages. As the result of juniper seed oil analysis, the acid value, saponification value, unsaponification value phosphorus contents, and refractive index were 91.04, 85.15, 15.52, 11.04 ppm, 1.47, respectively The content of neutral lipids, glycolipids and phospholipids were 85.4%, 12.2% and 2.4%, respectively. From the fatty acids analysis, the major fatty acids from the juniperseed harvested in August were lauric acid (31.9% ), palmitic acid (28.0% ), stearic acid (9.9%), and oleic acid (8.5%) . However, maturated seed oil harvested in October mainly consists of linoleic acid (47.6%), linolenic acid (17.6%), oleic acid (16.1%), and palmitic acid (11.9%). Upon these analyses, fatty acids composition of juniper seed oil depends on the seed maturation. According to volatile compounds analyses of essential oil extracted using steam distillation method and SPME, the major compounds were $\beta$-myrcene, $\alpha$-pinene, $\beta$-farnescene, $\beta$-cubebene, limonene, trans-caryo-phyllene, $\alpha$-terpinolene, camphene, sabinene, and $\beta$-pinene.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.237-242
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• 2005

This experiment was carried out to develop the fast and simple method for pesticide residue analysis by using solvent free solid injector (SFSI) and to validate the efficiency of the method developed for the residue analysis of the endocrine disruptor-like pesticides such as endosulfan, metribuzin, trifluralin and vinclozolin. The samples after freeze drying were sealed in glass capillary tubes and then introduced into the heated injector of gas chromatogaphy. The required pre-heating times were 1 min for endosulfan and trifluralin, 5 min for vinclozolin, and 10 min for metribuzin. The detection limits of endosulfan in chinese cabbages, metribuzin in lettuces, trifluralin in spinachs and vinclozolin in hot peppers were 0.05, 0.1, 0.05 and 0.05 ng, respectively and their recoveries were ranged from 74%, $98{\sim}107%$, $86{\sim}95%$ and $94{\sim}95%$, respectively. The detected level of metribuzine residue in field lettuce samples by using the SFSI was 0.6 ng/mg.

• Journal of Life Science
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• v.24 no.12
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• pp.1316-1324
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• 2014

Most beta-glucans obtained from various fruit bodies of mushrooms and mushroom mycelial cultures have high-molecular weight glycoproteins, conjugated with beta-glucans. We report that isoflavone-conjugated glycolproteins (designated as gluvone) were isolated and exhibited stronger anticarcinogenic activities. Agaricus blazei mycelia (ABM) was cultured in a liquid medium containing soybean flakes for 14 days. The liquid culture was autolyzed by incubating at $53^{\circ}C$ (pH 5.5) for 3 h. A crude glycoprotein (CGP) fraction with a cytotoxic effect on a mouse ascite cancer cell line (S-180) and a human breast cancer cell line (MCF-7) was isolated from the autolyzed ABM cultures by 80% ethanol treatment. Gluvone was isolated from the CGP with Sephadex G-75 column chromatography. It exhibited a stronger anticancer effect than CGP against the S-180 cell-induced female ICR mouse ascites carcinogenesis. Gluvone with 9,400 daltons was identified as a glycoprotein conjugated with isoflavone. According to HPLC and GC analysis, in conjunction with $^1H$-NMR spectral analysis, it contained 60% carbohydrates (glucose, fructose, and ribose), 31% protein, and 2% isoflavone (daidzein and genistein), which is a novel material. These results indicate that a strong anticarcinogenic gluvone was isolated from the autolyzed product of a submerged liquid culture of ABM, suggesting that autolysis could be a useful tool to produce antitumor agents.

• Journal of Korea Water Resources Association
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• v.33 no.3
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• pp.315-330
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• 2000

The GIUH (Geomorphologic Instantaneous Unit Hydrograph) is to be applied to the ungauged or insufficiently gauged basins. For tIris purpose, an accurate estimation of the charactenstlc velocity is one very important part, but any proper method for this has not been developed yet. In case that we have enough rainfall and runoff clata, the estimation of the characteristic velocity may be an easy job, but it is out of the purpose of the GIUH. Remindmg that the purpose of GIUH the characterisbc veloclty should be estimated based on the geomorpholog1c analysis and also be snnple for easy apphcation. In tIris research analysis cmd application of the GruH was given to several sub-basins in Wi-stream river basin, Gono, Donggok and Hyoryung. After deriving the characteristic velocity througn a optimizatlOn process with real data, it is compared w1th several velOCIties der1ved from geOlnoI1Jhoclimatic instantaneous unit hydrograph theory and several other concentration time formulae. The estimated charactenstic velocities using Kerby, Kim, KInematic Wave, and Brasby- Williams formulae found to g1ve the appropriate results. Hmvever, as the Kerby, and the Kinematic Wave require user's decision of the IvIanning's n value, the K1m and the Braby-Williams seem to be more applicable and recommended as characteristic velocity formula.