• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.395-401
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• 2002

Methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK) have been widely used as solvents in various industries. Biodegradation of MEK and MIBK by Pseudomonas putida KT-3, which could utilize MEK or MIBK as a sole carbon source, was characterized, and the cosubstrate interaction in MEK/MIBK mixture was also studied. Within the range of initial MEK concentration (from 0.5 to 5.5 mM), an increased substrate concentration increased the specific degradation rate of MEK by P putida KT-3 (from 3.15 to 10.58 mmol/g DCW$\cdot$h), but the rate sightly increased at 11.0 mM of initial MEK concentation (11.28 mmol/g DCW$\cdot$h). The similar degradation rates of MIBK (4.69-4.92 mmol/g DCW$\cdot$h) were obtained at more than 3.0 mM of initial MIBK concentation. Kinetic analysis on the degradation of MEK/MIBK mixture by P. putida KT-3 showed that MEK or MIBK acted as a competitive inhibitor. Maximum degradation rate ($V_{max}$), saturation constant ($K_{m}$) and inhibition constant ($K_{1}$) were as follows: $V_{max,MEK}$=12.94 mmol/g DCW$\cdot$h; $K_{m,MEK}$=1.72 mmol/L; $K_{l,MEK}$=1.30 mmol/L; $V_{max,MIBK}$=5.00 mmol/g-DCW$\cdot$h; $K_{m,MIBK}$=0.42 mmol/L; $K_{l,MEK}$=0.77 mmol/L.

• Journal of the Korean Society of Tobacco Science
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• v.35 no.1
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• pp.7-12
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• 2013

A Solid-phase micro extraction(SPME) was evaluated as a tool for headspace sampling of tobacco samples. Several experimental parameters (sampling temperature, pH, and type of SPME fibers) were optimized to improve sampling efficiency in two aspects ; maximum adsorption and selective adsorption of volatile organic acids onto SPME fibers. Among four types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate), Car/PDMS (Carboxen/Polydimethylsiioxane) and PDMS/DVB(Polydimethylsiioxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency. A variety of tobacco samples such as flue cured, burley and oriental were used in this study. The effect of these parameters was often dominated by the physical and chemical nature (volatility, polarity) of target compounds. This method allowed us to make important improvements in selectivity and sensitivity. The Car/PDMS fiber was shown to be the most efficient at extracting the 10 selected volatile organic acids. The parameters were optimized: $80^{\circ}C$ adsorption temperature, 30 min of adsorption time, $240^{\circ}C$ desorption temperature, 1 min of adsorption time.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.183-188
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• 2009

To produce ginsenoside-Rg$_3$ enriched edible yeast, ginseng steaming effluent (GSE) was used for yeast cultivation in this study. Four kinds of edible yeasts were cultured in sterilized GSE (2% w/v, pH 6.5), without any nutrient, for 48 h at 30$^{\circ}C$, and their growth and ginsenoside compositions were determined. Among the yeasts, Saccharomyces cerevisiae showed the highest growth in the GSE medium. 267.1 mg of Saccharomyces cerevisiae biomass was produced from 1 g of GSE solid and ginsenoside-Rg$_3$ contents was determined with 0.033 mg. Saccharomyces cerevisiae also showed the best overall acceptability, with a herbal and fermentative flavor and a slightly bitter taste. From these data, we conclude that Saccharomyces cerevisiae is the excellent strain for production of ginsenoside-Rg$_3$ enriched edible yeast using GSE.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.41-46
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• 1990

A bacterial isolate of DJ-12 capable of degrading 4-chlorobenzoic acid (4CBA) as well as 4-chlorobiphenyl (4CB) was used in this study. Its biodegradability of 4CBA was tested and the location of the genes coding for degradation of 4CBA was investigated by the nethod of in vivo cloning. The genes were found to be existed in the plasmid of pDJ121 which is about 65kb in size and which has 9, 11, 10, and 19 restriction sites for EcoRI, HindIII, SalI, and PstI, respectively. The hybrid plasmid of pDK450 was constructed by ligation of the EcoRI fragments of pDJ121 with pKT230 as a vector. In the recombinant cells selected through transformation of the hybrid vector into Pseudomonas putida KT2440, the 4CBA-degrading genes of DJ-12 were proved to be cloned and expressed in the Pseudomonas sp.

• Korean Journal of Environmental Biology
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• v.26 no.2
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• pp.87-93
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• 2008

To assess effects of contaminants on fish in Nakdong river, feral yellowfin goby Acanthogobius flavimanus were caugt in two different sites and its hepatic monooxygenase enzyme, including cytochrome P450 (CYP), NADPH-cytochrome P450 reductase (P450R), NADH-cytochrome b5 reductase (b5R), ethoxyresorufin deethylase (EROD), glutathione S-transferase (GST) were quantitatively determined. Gonadosomatic index (GSI), hepatosomatic index (HSI) and three sex steroid hormone (17$\beta$-estradiol, E2; testosterone, T; 11-ketotestosterone, 11-KT) levels of the fish were also investigated. HSI of fish from polluted site (site 1) were significantly higher than that of unpolluted site (site 2), but GSI levels were significantly lower in polluted site. No significant differences in plasma 11-KT and T levels were observed in two sites surveyed. E2 level was, however, significantly (p<0.05) higher in female fish from site 1 than site 2. In addition, hepatic EROD activity and CYP level of site 1 fish were lower than those of site 2 fish, whereas relatively high levels of P450R, b5R and GST activities were found in site 1. The results imply that yellowfin goby, especially female fish in Nakdong river estuary are affected from contaminants disrupting sex steroid hormone system.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.454-459
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• 1990

For the genetic multipurpose of antagonistic abilities of Pseudomom etutzeri YPL-1 aganist Fusarium solani causing root rot of many important crops by genetic engineering, optimal conditions for transformation of P-stutzeri YPL-1 by pKT230 were investigated. Maxium frequency of the transformation was achieved when cells were harvested at early exponential growth phase. The highest transformation efficiency was obtained when the competent cells were exposed to chilled transformation buffer containing 20 mM RbCI, 100 mM $CaCl_2$ and added l${\mu}g$/ml of plasmid DNA. The pH optimum for transformation was 6.5. When the bacterial cells that were incubated during 60 minutes for the competence were brought in contact with plasmid DNA, the transformations were obtained in the best frequency. It was formed that transformation frequency was 2 ~$6 \times 10^{-6}$ under the optimal conditions.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.51-57
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• 2015

In this paper, in order to design the A / D converter with a high resolution of 14 bits or more for the biological signal processing, CMOS delta sigma modulator that is a 1.8V power supply voltage - were designed. we propose a new structure of The fourth order delta-sigma modulator that needs four op amps but we use only two op amps. By using a time -interleaving technique, we can re-construct the circuit and reuse the op amps. Also, we proposed a KT/C noise reduction circuit to reduce the thermal noise from a noisy resistor. We adjust the size of sampling capacitor between sampling time and integrating time, so we can reduce almost a half of KT/C noise. The measurement results of the chip is fabricated using a Magna 0.18um CMOS n-well1 poly 6 metal process. Power consumption is $828{\mu}W$ from a 1.8V supply voltage. The peak SNDR is measured as a 75.7dB and 81.3dB of DR at 1kHz input frequency and 256kHz sampling frequency. Measurement results show that KT/C noise reduction circuit enhance the 3dB of SNDR. FOM of the circuit is calculated to be 142dB and 41pJ / step.

• Journal of dental hygiene science
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• v.6 no.1
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• pp.1-9
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• 2006

Cathepsin K (cat K) is the major cysteine protease expressed in osteoclasts and was thought to play a key role in matrix degradation during bone resorption. It was shown that the intracellular maturation of cat K was prevented by the cAMP antagonist, Rp-cAMP, and the protein kinase A (PKA) inhibitors of KT5720 and H89. In contrast, forskolin, a adenylate cyclase agonist, rather induced Cat K processing and maturation in osteoclasts. Furthermore, to determine whether cat K processing and maturation signaling involves protein kinase C (PKC), mouse total bone cells were treated with calphostin C, a specific inhibitor of PKC, however, no effect was observed, indicating that calphostin C did not affect to osteoclast-mediated cat K processing and maturation. Thus, it is indicated that the cAMP-PKA signaling pathway regulates cat K maturation in osteoclasts. Since secreted proenzymes have the potential to reenter the cell via M6P receptor, to prevent this possibility, it was tested cAMP antagonist Rp-cAMP and the PKA inhibitors KT5720 and H89 in the absence or presence of M6P. Inhibition of cat K processing by Rp-cAMP, KT5720, or H89 was observed in a dose-dependent manner. Furthermore, the addition of M6P resulted in enhanced potency of Rp-cAMP, KT5720 and H89. These dose-dependently inhibited in vitro bone resorption with a potency similar to that observed for inhibition of cat K processing.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.1-7
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of flue-cured tobacco as soon as possible. The data of eight chemical and five physical properties were collected from "Analysis of physical and chemical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 through 2006. Data of climatic factors from April to July in 10 districts were collected from Korea Meteorological Adminstration. Except for yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, in nicotine content, and in filling value, 90% in total nitrogen content, and 70% in total sugar content. These results suggest that the regression equations may be useful to predict the average content of twelve grades for eight chemical and four physical properties by climatic factors during the growing season of flue-cured tobacco at the beginning of August.

• Journal of the Korean Arthroscopy Society
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• v.17 no.1
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• pp.18-23
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• 2013

Purpose: The purpose of this study is to evaluate the usefulness of anatomical single bundle anterior cruciate ligament (ACL) reconstruction using outside-in technique by clinical outcome analysis. Materials and Methods: From July 2009 to July 2010, 41 cases of single bundle ACL reconstruction using outside-in technique which were followed minimum 1 year were enrolled. Clinical results were evaluated using International Knee Documentation Committee (IKDC) subjective knee evaluation score, Lysholm score, pivot shift test, one leg hop test, KT-1000 arthrometer test, Telos stress arthrometer test. Results: IKDC subjective knee score and Lysholm score were improved to $86.1{\pm}2.1$ and $91.2{\pm}3.8$ postoperatively (p<0.0001 and p<0.0001, respectively). KT-1000 arthrometer test and Telos stress arthrometer test also were improved to $2.2{\pm}0.9\;mm$ and $2.3{\pm}1.2\;mm$ (p<0.0001 and p<0.0001, respectively). Pivot shift test and one leg hop test revealed good results. Conclusion: Anatomical single bundle anterior cruciate ligament reconstruction using outside-in technique showed good clinical results, so it was considered available method.