• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.182-185
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• 2005

Bioassay-guided isolation of the dried roots of Aralia continentalis led to the isolation of (-)-pimara-8(14), 15dien-19-oic acid (continentalic acid) and $(24E)-Stigmasta-5,22-dien-3{\beta}-ol$ (stagmasterol). Their structures were elucidated using $^1H-NMR$, $^{13}C-NMR$, UV and mass spectra analyses. The gram-positive bacterial, including methicilline-resistant (MRSA), were more sensitive to the continentalic acid and stagmasterol than gram-negative bacterial.

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.73-83
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• 2005

The fish fauna and the dynamics of fish community structure in Lake Uiam, Korea, were investigated from July 2003 to May 2004. During the surveyed period, 41 species belonging to 13 families were collected. There were 11 Korean endemic species (26.8%), including Rhodeusuyekii, Acheilognathus yamatsutae, Sarcocheilichthys nigripinis morii, Squalidus gracilis majimae, Squalidus japonicus coreanus, Microphysogobio yaluensis, Iksookimia koreensis, Koreocobitis rotundicaudata, Silurus microdorsalis, Liobagrus andersoni, and Odontobutis platycephala. Dominant species were Hemibarbus labeo (16.2%), Zacco platypus (13.8%), A. yamatsutae (11.8%), S. gracilis majimae (10.4%), Pungtungia herzi (5.8%), and Hypomesus olidus (4.3%). The biomass of collected fishes were H. labeo (35.9 kg), Cyprinus carpio (22.5 kg), Micropterus salmoides (5.5 kg), Lepomis macrochirus (5.2 kg), Carassius cuvieri (3.3 kg) and Z. platypus (2.4 kg). Of the 9 introduced fishes in Lake Uiam, Cyprinus carpio (Israeli type), Carassius cuvieri, Oncorhynchus mykiss irideus, Lepomis macrochirus, and Micropterus salmoides originated in foreign countries, but Anguilla japonica, Hypomesus olidus, Chaenogobius urotaenius, and Rhinogobius giurinus were introduced from other native river systems.

• Fisheries and Aquatic Sciences
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• v.20 no.7
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• pp.14.1-14.8
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• 2017

In this study, marine tunicate Styela clava hydrolysate was produced by an environment friendly and green technology, pressurized hot water hydrolysis (PHWH) at different temperatures ($125-275^{\circ}C$) and pressure 50 bar. A wide range of physico-chemical and bio-functional properties such as color, pH, protein content, total carbohydrate content, reducing sugar content, and radical scavenging activities of the produced hydrolysates were evaluated. The appearance (color) of hydrolysates varied depending on the temperature; hydrolysates obtained at $125-150^{\circ}C$ were lighter, whereas at $175^{\circ}C$ gave reddish-yellow, and $225^{\circ}C$ gave dark brown hydrolysates. The $L^*$ (lightness), $a^*$ (red-green), and $b^*$ (yellow-blue) values of the hydrolysates varied between 35.20 and 50.21, -0.28 and 9.59, and 6.45 and 28.82, respectively. The pH values of S. clava hydrolysates varied from 6.45 ($125^{\circ}C$) to 8.96 ($275^{\circ}C$) and the values were found to be increased as the temperature was increased. The hydrolysis efficiency of S. clava hydrolysate was ranged from 46.05 to 88.67% and the highest value was found at $250^{\circ}C$. The highest protein, total carbohydrate content, and reducing sugar content of the hydrolysates were found 4.52 mg/g bovine, 11.48 mg/g and 2.77 mg/g at 175, and 200 and $200^{\circ}C$, respectively. Hydrolysates obtained at lower temperature showed poor radical scavenging activity and the highest DPPH, ABTS, and FRAP activities were obtained 10.25, 14.06, and 10.91 mg trolox equivalent/g hydrolysate (dry matter basis), respectively. Therefore, S. clava hydrolysate obtained by PHWH at $225-250^{\circ}C$ and 50 bar is recommended for bio-functional food supplement preparation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.1
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• pp.7-13
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• 1978

Changes in contents of general components of comfrey cultured in Korea were experimented and amino acids were analyzed by thin layer chromatography (T.L.C.) and gas chromatography (G.L.C.). The results obtained were as follows; 1. General components of comfrey such as moisture, fat, protein, carbohydrate, crude fiber and total ash were 13.20, 2.22, 22.30, 37.62, 9.38 and 15.06%. respectively, after 60 days growth. 2. The root of comfrey after 60 days contained 6.03% of alanine, 2.24% valine, 10.77% arginine, 2.96% glycine, 4.08% histidine. 1.54% isoleucine, 0.58% cystein, 1.72% methionine, 7.55% aspartic acid, 7.81% glutamic acid and 4.65% lysine in the gas chromatographic analysis of amino acid composition 3. The crude protein was decreased after 60 days of growth whereas the contents of carbohydrate, crude fiber and total ash were increased. 4. The total amount of amino acids in root was greater than that in leaf of comfrey.

• Korean Journal of Materials Research
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• v.5 no.6
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• pp.690-698
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• 1995

The Poly-S $i_{1-x}$G $e_{x}$ thin films were deposited on oxidized Si wafer by RTCVD(rapid thermal chemical vapor deposition) using Si $H_4$and Ge $H_4$, at 450 ~5$50^{\circ}C$. The variation of Ge mole fraction and the deposition rate of S $i_{1-x}$G $e_{x}$ thin film were studied as a function of the deposition temperature and the Ge $H_4$/Si $H_4$input ratio, and the crystal phase and the surface roughness were studied by XRD and AFM(atomic force microscopy), respectively. The experimental results showed that the activation energy for the deposition of poly-S $i_{1-x}$G $e_{x}$ was about 32~37Kca /mol and the deposition rate of S $i_{1-x}$G $e_{x}$ thin films was increased with increasing the deposition temperature and the input ratio. From the analysis of composition, it was known that the Ge mole fraction within the poly-S $i_{1-x}$G $e_{x}$ thin film was decreased with decreasing the input ratio and increasing the deposition temperature. As-deposited S $i_{1-x}$G $e_{x}$ thin films were polycrystalline over the entire experimental range. But those were amorphous at the deposition temperature of 450, 475$^{\circ}C$ and the input ratio of 0.05. By adding the Ge $H_4$, poly-S $i_{1-x}$G $e_{x}$ thin film were deposited at relatively lower deposition temperatures($\leq$ 5$50^{\circ}C$) than those of conventional poly-Si(>$600^{\circ}C$). From surface roughness measurement of poly-S $i_{1-x}$G $e_{x}$ it was found that the surface roughness( $R_{i}$ ) increased with increasing the deposition temperature and input ratio.and input ratio.

• Journal of Life Science
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• v.14 no.4
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• pp.593-607
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• 2004

The nucleotide sequence for a nuclear-encoded small subunit rDNA (SSU rDNA) was determined for 43 species of the class Dinophyceae, including harmful algae Cochlodinium polykrikoides and Gyrodinium aureolum. These sequences and data analyses were performed by parsimony, distances and maximum likelihood methods in PHYLIP (Phylogenetic Inference Package) version 3.573c. The species Noctiluca scintillans, Gonyaulax spinifern and Crypthecodinium cohnii occupied a basal position within the Dino- phyceae in our analyses. The genera Alexandrium and Symbiodinium were monophyletic (supported by a bootstrap value of >70%), whereas the genera Gymnedinium and Gyrodinium formed polyphyletic nodes, for which bootstrap support was strong (>70%) in the neighbor-joining and maximum likelihood methods except for the PHYLIP parsimony analysis (=59%). The sequence divergence between G. aureolum and G. dorsum/ G. galathenum was the largest at 7.4% (45 bp), whereas G. aureolum and G. mikimotoi showed an extremely low value of genetic divergence of 0.9% (5 bp). The genetic divergence between C. polykrikoides and G. aureolum was a low value of 5.2% (31 bp). In the phylogenetic analysis, the placement of G. aureolum and C. polykrikoides was closer to the genus Gymnodinium than to the genus Gyrodinium, which was supported by a moderate bootstrap value.

• Honam Mathematical Journal
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• v.10 no.1
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• pp.23-30
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• 1988

Let C[C, D] and $S^{*}[C,\;D]$ denote the classes of functions g, g(0)=1-g'(0)0=0, analytic in the unit disc E such that $\frac{(zg{\prime}(z)){\prime}}{g{\prime}(z)}$ and $\frac{zg{\prime}(z)}{g(z)}$ are subordinate to $\frac{1+Cz}{1+Dz{\prime}}$ $z{\in}E$, respectively. In this paper, the classes K[A,B;C,D] and $C^{*}[A,B;C,D]$, $-1{\leq}B<A{\leq}1$; $-1{\leq}D<C{\leq}1$, are defined. The functions in these classes are close-to-convex. Using the properties of convolution operators, we deal with some problems for our classes.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.89-94
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• 2013

The present study was undertaken to elucidate the mechanisms underlying the cholesterol-lowering effect of S-allylmercaptocysteine (SAMC) derived from aged garlic. Rat hepotocytes and HepG2 cells were used to determine the short-term effects of SAMC on [$^{14}C$] acetate incorporation into cholesterol, and several enzymatic steps. The cells were grown in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum and treated with 20, 40, 60 and 80 ${\mu}g/ml$ of SAMC. At concentration of 20~40 ${\mu}g/ml$, no significant cells viability effect was noted during those incubation periods. However, at a concentration 60 ${\mu}g/ml$, cell viability decreased approximately 50% compared with the control. The treatment of cells with 5, 10, 15, and 20 ${\mu}g/ml$ of SAMC resulted in a marked of [$^{14}C$]-acetate incorporation into cholesterol. At concentration of 15 ${\mu}g/ml$, the cholesterol synthesis was inhibited 79% in cells. The activities of lipogenic enzymes, fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G3PDH) were measured in culture hepatocytes treated with the inhibitors. The activity of FAS in cells treated with 0.95 nmol SAMC was 19% lower than that of nontreated cells, and no affected G6PDH activity, 3-hydroxy-3-methylglutaryl Co A activity was decreased at concentration dependant manner. The present study demonstrates that SAMC is effective in inhibiting cholesterol biosynthesis.

• Journal of Magnetics
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• v.5 no.2
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• pp.50-54
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• 2000

NiMn-pinned spin valve films consisting of a layered glass/NiFe/Co/Cu/Co/NiFe/NiMn/Ta stack were made by do magnetron sputtering. After deposition, the structure was annealed in a series of cycles each including three hours at $220^\circ C, 2\times10^{-6}$ Torr, in a field of 350 Oe, to create an ordered antiferromagnetic structure in the NiMn layer and produce a strong unidirectional pinning field in the pinned magnetic layer, Optimum spin valve properties were obtained after seven annealing cycles, or 21 hours at $220^\circ C$, and were : MR ratio 1%, exchange coupling field 620 Oe, and coercivity of pinned layer 250 Oe. The exchange coupling field remained constant up to an operating temperature of $175^\circ C$, and the blocking temperature was about $380^\circ C$.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.343-347
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• 2008

Recently, Sunshik has been issued because of easy-cook and well-being food. Sunshik basically was made of the heated cereals. Amount of spore-forming Bacillus cereus was detected and it has been caused some problem of food safety. B. cereus was isolate from 57 out of 161 Sunshik samples resulting in the isolation rate of 35.4%. Quantitative analysis of 57 samples showed that 21 samples were less than 100 CFU/g, 33 samples were between 100 and 1,000 CFU/g and distinctively even 3 (1.9%) samples had over 1,000 CFU/g. Typical morphology of B. cereus isolated from Sunshik was observed on MYP agar and then further characteristics was identified by using VITEK 2 (Biomeriux, France). 53 strains out of 57 strains isolated from Sunshik (about 93.0%) produced diarrheal enterotoxin in brain heart infusion broth which was detected by the Bacillus cereus enterotoxin reversed passive latex agglutination test kit (Oxoid England). The D-values of the B. cereus spores were $75^{\circ}C$ (37.1mim), $80^{\circ}C$ (22.5mim), $85^{\circ}C$ (4.9mim), and $90^{\circ}C$ (3.1mim) respectively. The Z-value was calculated $12.8^{\circ}C$ in Sunshik sample inoculated with B. cereus. Therefore, the management of B. cereus in Sunshik is required for the food-safety.