• Electrical & Electronic Materials
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• v.9 no.2
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• pp.152-158
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• 1996

Optical absorption and photoconductivity spectra of undoped and Co-doped Cd$_{4}$GeSe$_{6}$ single crystals, grown by the chemical transport reaction using iodine as a transporting agent, were investigated. At 20K, the optical energy gaps of the single crystals are 1.934eV for Cd$_{4}$GeSe$_{6}$ and 1.815eV for Cd$_{4}$GeSe$_{6}$ :Co$^{2+}$. The photoconductivity spectra of these single crystals were closely investigated over the temperature range 20-290K. At 20K, the photoconductivity peaks were located at 1.797eV, 1.347eV for Cd$_{4}$GeSe$_{6}$ and 1.815eV, I,.57eV, 1.46eV and 1.38eV for Cd$_{4}$GeSe$_{6}$ :Co$^{2+}$, respectively.ely.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1063-1072
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• 2012

Effective population size ($N_e$) is an important measure to understand population structure and genetic variability in animal species. The objective of this study was to estimate $N_e$ in Sapsaree dogs using the information of rate of inbreeding and genomic data that were obtained from pedigree and the Illumina CanineSNP20 (20K) and CanineHD (170K) beadchips, respectively. Three SNP panels, i.e. Sap134 (20K), Sap60 (170K), and Sap183 (the combined panel from the 20K and 170K), were used to genotype 134, 60, and 183 animal samples, respectively. The $N_e$ estimates based on inbreeding rate ranged from 16 to 51 about five to 13 generations ago. With the use of SNP genotypes, two methods were applied for $N_e$ estimation, i.e. pair-wise $r^2$ values using a simple expectation of distance and $r^2$ values under a non-linear regression with respective distances assuming a finite population size. The average pair-wise $N_e$ estimates across generations using the pairs of SNPs that were located within 5 Mb in the Sap134, Sap60, and Sap183 panels, were 1,486, 1,025 and 1,293, respectively. Under the non-linear regression method, the average $N_e$ estimates were 1,601, 528, and 1,129 for the respective panels. Also, the point estimates of past $N_e$ at 5, 20, and 50 generations ago ranged between 64 to 75, 245 to 286, and 573 to 646, respectively, indicating a significant $N_e$ reduction in the last several generations. These results suggest a strong necessity for minimizing inbreeding through the application of genomic selection or other breeding strategies to increase $N_e$, so as to maintain genetic variation and to avoid future bottlenecks in the Sapsaree population.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.131-137
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• 2005

Seasonal occurrence of the egg parasitoid of bugs, Ooencyrtus nezarae (Hymenoptera: Encyrtidae), was monitored at soybean fields and university campus using traps baited with aggregation pheromone of bean bug, Riptortus clavatus, in Jinju, Gyeongnam province, Korea. The female O. nezarae captured at university campus in 2003 and 2004 was 317.5 and 103.4 times as many as males, respectively, and it was 12.6 times at soybean field in 2004. The female began to occur from late August, showing its peak around September 20 at soybean field in 2004. At university campus in 2003 and 2004, the female began to occur from mid or late August, and showed its peak early or mid September. At the two monitoring sites the catches of female sharply declined after October The E2HZ3H only showed attractiveness to O. nezarae, among three components of the aggregation pheromone of bean bug, (E)-2-hexenyl (Z)-3-hexenoate (E2HZ3H), (E)-2-hexenyl (E)-2-hexenoate (E2HE2H), and myristyl isobutyrate (MI). A mixture in a ratio of 20:20:10 or 16.7:16.7:16.7 of E2HZ3H:E2HE2H:MI attracted significantly more females than the mixture of 7:36:7 ratio did. This higher attractiveness of the former two blends may be attributed to the higher amounts of E2HZ3H in the blends.

• Journal of Life Science
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• v.14 no.3
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• pp.445-452
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• 2004

We investigated the cytotoxic effects of seven furanoterpenoids 〔sarcotin A, epi-sarcotin A, ircinin-1, epi-sarcotrine B, sarcotin I, (8E, l3Z, 20Z)-strobilinin/(7E,l3Z, 20Z)-felixinin and (7E,12E,18R,20Z)-variabilin〕 isolated from the sponge Sarcotragus sp. (the order Dictyoceratida) on the growth of A549 human lung carcinoma cells. MTT data revealed that sarcotin A and (7E,12E,18R,20Z)-variabilin exhibited higher potencies on the anti-proliferative activities than the other compounds in A549 cells. The growth inhibition by treatment with compounds (especially epi-sarcotin A, ircinin-1 and epi-sarcotrine B) were associated with the induction of apoptotic cell death through the concentration-dependent increase of Bax/Bcl-2 ratio in a p53-dependent or independent pathway Additionally, epi-sarcotin A and ircinin-1 strongly inhibited the levels of cyclooxygenase (COX)-2 expression without alteration of COX-1. Taken together, the results suggest that the furanoterpenoids from the marine sponge have strong potentials as candidates for anti-cancer drugs.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.351-357
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• 2011

This study was carried out to investigate the effective extraction condition for increase of phytoecdysteroids from fronds of Matteuccia struthiopteris (FMS) and Osmunda japonica (FOJ). Lyophilizated fronds were mixed with three different solvents (MeOH, 80% EtOH or water) and then extraction was carried out by using six different methods, such as, immersion (room temp.), heating (60$^{\circ}C$), stirring (200 rpm) for 6 h, or sonication in 42 kHz ultrasonic bath for 15, 30 and 45 minutes. Contents of 20-hydroxyecdysone (20E) and ponasterone A (PonA) were measured by using HPLC after purification of the extracts by $C_{18}$ cartridge. Altogether, our results indicate that the extraction using sonication with MeOH as a solvent (for 30 minutes) was the most effective condition for 20E and PonA from both MFS and FOJ. Resulting contents of 20E from FMS and FOJ were 66.76 and 104.48 ${\mu}g{\cdot}g^{-1}$ and PonA were 53.43 and 43.82 ${\mu}g{\cdot}g^{-1}$, respectively.

• Biomedical Science Letters
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• v.26 no.4
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• pp.319-326
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• 2020

This study was conducted to develop a new functional material by optimizing the conditions for high concentrations of chlorogenic acid and eleutheroside E in Acanthopanax koreanum stem. The total phenolic compound content was the highest in the 20 hours sonication Acanthopanax koreanum stem extract (UAK-20). In addition, eleutheroside E, a typical functional ingredient of Cortex Acanthopanacis, in the 20 hours treated Acanthopanax koreanum stem extract showed the highest content at 1.646%. However, another functional ingredient, chlorogenic acid, showed the highest content of 2.625% in 1 hour treated Acanthopanax koreanum stem extract. Therefore, it is considered that the optimal conditions for high concentrations of total phenolic compound and eleutheroside E are 20 hours sonication Acanthopanax koreanum stem extract.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.342-343
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• 2017

Bacillus velezensis T20E-257 was isolated from the root tissue of a tomato plant and exhibited plant growth-promoting activity. Here we present the complete genome of strain T20E-257. The genome contains 3,900,066 base pairs with a G + C content of 46.7% in 2 contigs. The genome includes 3,708 coding sequences, 27 rRNAs, and 86 tRNAs. We found gene clusters encoding secondary metabolites with an antimicrobial activity and genes related to the production of indole-3-acetic acid and 2,3-butanediol, which play a role in plant growth and health.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.18 no.1
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• pp.42-63
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• 1992

In order to investigate the effect of nonionic surfactants on the antimicrobial activity of preservatives in the presence and absence of p.0.E(20) Sorbitan fatty acid ester commonly used in cosmetics and pharmaceutical systems, these experiments were carried out by determining Minimum Inhibitory Concentration(MIC) values and MIC values of adaptation against test organisms. And also the inactivation of the preservative against each microorganism in formula added with various concentrations of P.0.E(20) Sorbitan monostearate were measured by use of a preservative death time curve The results obtained were as fort low : 1) Nonionic surfactant inactivated Methylparaben to varying extents, but not Imidazolidinyl urea. 2) A combined preservative system was inactivated to a little extent (range of 0.16-0.20% Conc.), no adaptation was observed for the 5. aureus ATCC 6538. Imidazolidinyl urea complex combined with Methylparaben had a broad antibacterial spectrum against the Gram(.) and the Gram(-) bacteria It was found that preservatives had a synergistic effect by use of mixed form of preservatives, 3) In formula preserved with 0.2% Methylparaben containing 0.5, 1.0 and 2.0% P.0.E(20) Sorbitan monostearate, E. coli ATCC 10s36 and P. aeruginosa NCTC 10490 died quickly within in 2hr 4) However, from Fig.5, S. aereus ATCC 6538 died more slowly within increasing surfactant concentration and the D-values(Decimal reduction time) were 5.2, 8 and 14 hr. for samples containing 0.5, 1 0 and 2.0% P 0. E(20) Sorbitan monostearate, respectively. 5) In the case of Methylparaben, no adaptation for the E. coli ATCC 10536 6) All of the nonionic surfactant, p.0. E(20) Sorbitan fatty acid ester used in the experiments decreased the effectiveness of Methylparaben, but not of Imidazolidinyl urea.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.657-663
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• 1996

Pseudomonas sp. P20 isolated from the polluted environment is capable of degrading biphenyl and 4-chlorobiphenyl. The pcbABCD genes responsible for degradation of biphenyl and 4-chlorobiphenyl were cloned using pBluescript SK(+) from the chromosomal DNA of Pseudomonas sp. P20 to construct pCK1 and pCK102, harbouring pcbABCD and pcbCD, respectively. The 2, 3-DHBP dioxygenase gene, pcbC, was cloned again from pCK102 by using pKT230 which is known as a shuttle vector and pKK1 hybrid plasmid was constructed. The E. coli KK1 transformant obtained by transforming the pKK1 into E. coli XL1-Blue showed 2, 3-DHBP dioxygenase activity. The specific 2, 3-DHBP dioxygenase activity of E. coli KK1 was similar to that of the E. coli CK102, but much higher than those of the natural isolates, Pseudomonas sp. DJ-12 and Pseudomonas sp. P20.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1337-1342
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• 1990

This paper deals with control system design strategy for electrolmaginetic suspension (E.M.S.) system. For a successful control of E.M.S. system, the nature of E.M.S. system is deeply studied in the view point of non-linear, open-loop unstable, time-varying, non-minimum phase system. To find a special control treatment for E.M.S. system, analyses and simulations for various models are carried out. As one of the successful candidates, adaptive control concept is introduced and sample hardware system using digital signal processor is implemented.