• Toxicological Research
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• v.18 no.4
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• pp.349-354
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• 2002

Inflammatory bowel disease (IBD) is a multifactorial disorder with unknown etiology and pathogenesis. Eupatilin, a kind of flavonoids, has been known to be effective for chronic diarrhea in Korea. In this study, we have investigated the genotoxicity of DA-6034, a new synthetic derivative of Eupatilin, wing in vitro and in viuo system such as Ames reverse mutation test, chromosomal aberration test and micronucleus test. in Ames reverse mutation test, DA-6034 treatment at the dose range up to 5,000 $\mu\textrm{g}$/ plate did not induced mutagenicity in Salmonella typhimurium TA98, TA100, TA102, TA1535, TA1537 with and without metabolic activation. Any significant aberration wasn't observed in chinese hamster lung(CHL) fibroblast cells treated with DA-6034 at the concentration of 5, 2.5, 1.25 mg/ml both in the absence and presence of metabolic activation system. In mouse micronucleus test, no significant increase in the occurrence of micronucleated polychromatic erythrocytes was observed in ICR male mice orally administered with DA-6034 of the doses of 2.0, 1.0, 0.5 g/kg. These results indicate that DA-6034 has no mutagenic potential under the condition in this study.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.2
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• pp.134-138
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• 1994

$LiTaO_3 (LT)$ single crystals (Y, X-axis) were grown from the congruent composition, 48.65 mole %, $Li_2O$ for SAW (Surface Acoustic Wave) applications. Basic SAW filters were fabricated on the RIST prepared LT wafers (Y-cut) using phtolithography. SAW filter performance was evaluated. The results were compared of the SAW characteristics between RIST prepared LT wafer (Y-cut) and commercial Yamaju wafer (Y-cut). The SAW filter prepared on the RIST grown LT wafer was shown better SAW performances than that of Yamaju wafer.

• International journal of advanced smart convergence
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• v.6 no.4
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• pp.41-49
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• 2017

In this paper I applies Borer (1993)'s way of classifying English intransitive action verbs such as 'run', walk, among many others, to the corresponding Korean intransitive action verbs such as 'tali-ta' and 'keət-ta', and show how they are different from - or similar with - each other in terms of syntactic structures and verb classification. Unlike the English verb 'run' which can be classified into an unaccusative verb as well as an unergative verb in Borer's theory, the corresponding Korean verbs 'tali-ta' or 't'wi-ta' can behave not only as an unergative and unauucsative verb, but also it can behave as a transitive verb. Though Borer's perspective on classification of verb types may be thought of as somewhat radical mostly due to its heavy dependency on aspectual representation of a whole sentence which a verb is just part of, it is clearly suggesting a new and great insight into the controversial topic of classification of verb types. So it is worth adopting this insightful perspective for the analysis of corresponding Korean verbs and seeing if it also works for the Korean ones.

• The Korean Journal of Community Living Science
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• v.26 no.4
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• pp.633-645
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• 2015

This study investigates the genotoxicity of crude antifungal compounds produced by Lactobacillus plantarum AF1 (L.plantarum AF1) and Lactobacillus plantarum HD1 (L. plantarum HD1) isolated from kimchi. The genetic toxicity of crude antifungal compounds was evaluated in bacterial reverse mutation in Salmonella and Escherichia spp., chromosome aberrations in Chinese hamster lung cells, and micronucleous formations in mice. In bacterial reversion assays with Salmonella Typhimurium TA98, TA100, TA1535, TA1537, and WP2uvrA, crude antifungal compounds did not increase the number of revertant colonies in both the absence and presence of the 59 metabolic activation system. In the chromosome aberration test with Chinese hamster lung cells, crude antifungal compounds showed no increase in the frequency of chromosome aberrations in the short-period test with/without the S9 mix or in the continuos test. In the in vivo mouse micronucleus assay, crude antifungal compounds showed no increase in the frequency of polychromatic erythrocytes with micronuclei. The results show that crude antifungal compounds produced by L. plantarum AF1 and L. plantarum HD1 did not induce any genotoxicity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.97-100
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• 2001

This paper presents the characteristics of Ta-N thin-film strain gauges as high-temperature strain gauges, which were deposited on Si substrate by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(4~16%)$N_2$). These films were annealed for 1 hour in $2{\times}10^{-6}$ Torr vaccum furnace range $500\sim1000^{\circ}C$. The optimized conditions of Ta-N thin-film strain gauges were annealing condition($900^{\circ}C$, 1 hr.) in 8% $N_2$ gas flow ratio deposition atmosphere. Under optimum conditions, the Ta-N thin-films for strain gauges is obtained a high resistivity, $\rho=768.93$ ${\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=-84 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=4.12.

• Toxicological Research
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• v.29 no.4
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• pp.279-283
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• 2013

Acanthopanax koreanum Nakai, a well known traditional herb grown in Jeju Island, South of Korea, has been used as a tonic and sedative agent, as well as in the treatment of diabetes and immune diseases. Mutagenicity of two lignans, syringaresinol and tortoside A isolated from A. koreanum, was assessed using Salmonella/microsome (Ames) test. Tester strains used were Salmonella typhimurium TA98, TA100, TA1535, and Escherichia coli WP2uvrA. The mutagenic activity was determined both in the absence or presence of S9 mixture. As a result, tortoside A did not cause any increase in the number of $his^+$ revertants in S. typhimurium and E. coli WP2uvrA strains in the presence or absence of S9 mix, compared to the controls. Similarly, low concentrations of syringaresinol (750 and 1,500 ${\mu}g$/plate) did not show any mutagenic properties in all bacterial strains, in the presence or absence of S9 mixture. However, in the high concentration of syringaresinol (3,000 ${\mu}g$/plate), the number of revertants were increased in TA1535 strains, in the absence of S9 metabolic activation. Therefore, in vivo experiments such as comet assay are needed to further determine the genotoxic/carciogenic potential of syringaresinol isolated from A. koreanum.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.668-673
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• 1995

$UO_2$-CeO$_2$ 모의혼합분말에 첨가제를 미량 첨가하여 소결체의 미세구조 변화를 $UO_2$분말의 경우와 비교, 관찰하였다. 소결 첨가제로서 Ta, Ti 및 Nb를 사용하였으며, 이들을 미세한 산화물의 형태로 $UO_2$ 및 $UO_2$-CeO$_2$에 첨가하여 환원성 및 산화성 분위기에서 각각 소결하였다. Ta, Ti 및 Nb는 환원소결에서 $UO_2$의 결정립을 성장시켰으나 산화소결에서는 첨가효과가 크게 나타나지 않았다. $UO_2$-0.lw%TiO$_2$와 $UO_2$-0.6w%Ta$_2$O$_{5}$의 환원소결체에서 eutectic phase가 관찰되었으나 산화소결체에서는 나타나지 않았다. $UO_2$-4wt%CeO$_2$의 환원소결에서는 Ti만이 결정립성장에 기여하는 것으로 나타났으며 Ta, Nb와 같이 $UO_2$에 치환형으로 고유되는 원소는 Ce 이온과 Cluster를 형성함으로 결정립성장에 거의 기여하지 못하고, Ti와 같이 UO2$_2$ 침입형으로 고용되는 원소는 일부가 인접한 Ce$_{U}$' 이온과 cluster를 형성하더라도 나머지가 V$_{U}$'의 형성에 기여하므로서 결정립을 성장시킬 수 있다.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.50-53
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• 1996

A cultured milk product was made by fennenting 10$\%$ reconstituted skim milk with Lactococcus lactis subsp. lactis TA29 and Saccharomyces exiguus SK2. L. lactis TA29 and S. exiguus SK2 grew up to 1.0 $\times 10^9\;and\;2.0 \times 10^6$ cfu/ml, respectively. After the fermentation 21$\%$ of lactose was hydrolyzed, pH was lowered to 4.2, and titratable acidity and alcohol concentration were increased to 0.96 and 0.023$\%$, respectively. When the fermented milk was stored at $4{\circ}C$ for 9 days, the viable cell counts for L. lactis TA29 and S. exiguus SK2 were $6.5 \times 10^5\;and\;1.6 \times 10^6$ cfu/rnl, respectively. The alcoholic fermented milk prepared in this experiment was more inhibitory against some pathogenic bacteria including C. perfringens than commercial yoghurt products tested.

• Resources Recycling
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• v.16 no.6
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• pp.34-38
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• 2007

For recycling of tantalum from obsolete condenser, physical separations and chlorination of tantalum scraps with $Cl_2$ and $CCl_4$ were investigated. The recovery ratio of tantalum from obsolete condenser was 98% by using a multidisciplinary process of crushing by stamp mill, wet gravity separation by the shaking table, and air classification. In the chlorination reaction of non-oxidized Ta anode with $Cl_2$, the highest weight loss ratio is at least 60%, while in the chlorination reaction of Ta anode with $CCl_4$, the reaction rate for the oxidized Ta anode is faster than that of the non-oxidized Ta anode.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.280-285
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• 1991

This study was undertaken to measure the degree of browning and mutagenicity by Ames test using Salmonella typhimurium TA 98 and TA 100 strains for roasted barley and sesame seeds used as food materials. The degree of browning of roasted barley for barley tea on the market showed a wide variation; barley for restaurant-use was heavily roasted (5 times) in comparison with homeuse barley. Sesame seeds for oil extraction were more roasted (4 times) than those for seasoning. Water-, ethanol- and ether-soluble fractions from roasted barley and sesame seeds did not show any signs of mutagenicity, even at the extremely high concentrations of the extracts.