• The Korean Journal of Ecology
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• v.27 no.3
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• pp.147-153
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• 2004

The objective of this study was to understand differences among three half-sib families of Betula schmidtii seedlings in the effect of three Cd levels on growth and photosynthesis. One-year-old seedlings of B. schmidtii were treated with 0, 0.4 and 0.8 mM CdSO$_4$ㆍ8/3$H_2O$ for two months. Growth and physiological responses to Cd treatment levels of three families determined using dry weight, relative height growth rate(RHGR), apparent quantum yield and carboxylation efficiency. The B. schmidtii seedlings exposed to 0.4 and 0.8 mM Cd showed statisticall significant decrease in dry weight and RHGR relative to controls. In addition, the growth inhibition of B. schmidtii seedlings was accompanied by a significant decrease in net photosynthesis measured as $CO_2$ assimilation. Apparent quantum yield and carboxylation efficiency were also affected by Cd treatment, undergoing a significant and progressive reduction with increasing Cd concentrations in all families. We also found significant difference among three families of B. schmidtii in growth, biomass and photosynthesis when exposed to Cd stress. Therefore the present study showed that the difference in Cd tolerance among families might be attributed to genetic factor in response to Cd stress.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.1
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• pp.11-17
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• 2004

This study was conducted to determine the relationship of stomatal responses, photosynthesis, and intercellular $CO_2$ concentration( $C_{i}$) of Betula Species to ozone exposure. Five Betula Species(B. costata, B. davurica, B. schmidtii, B. platyphylla var, iaponica and B, ermani) were grown in the greenhouse. One-year-old potted seedlings of the five Betula Species were exposed to ozone(100 pub) for 8 hours da $y^{-1}$ for 5 weeks in a fumigation chamber. Net photosynthesis was significantly different among species and treatments from early in the period of the fumigation. Stomatal conductance and transpiration rate differences among species and treatments became significant after three weeks of fumigation. $C_{i}$ was significantly different only among treatments; $C_{i}$ of four species, except for B. davurica, was higher than that of control plants. Carboxylation efficiency and photo-respiration rate were significantly different among species or treatments; carboxylation efficiency and photo-respiration rate of the five Betula Species were decreased by ozone treatment. It was concluded that stomatal closure of Betula Species may be the result of the reduction of photosynthesis and rubisco activity and the resulting increase of $C_{i}$. The higher $C_{i}$ likely resulted from reduced photosynthesis because of physiological processes.ocesses.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.156-163
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• 2005

This study was conducted to compare the physiological and biochemical responses of P. orientalis and L. tulipifera in response to ozone. One-year-old seedlings of P. orientalis and L. tulipifera were exposed to 100 ppb ozone concentration for 2, 4, or 8 hr/day for 1 week. Photosynthesis, stomatal conductance and ozone uptake rate were measured daily, and chlorophyll fluorescence, carboxylation efficiency, chlorophyll content, and SOD activity were measured after 1 week. In P. orientalis, photosynthesis and stomatal conductance were not decreased in the 2h/day ozone treatment, but the L. tulipifera response was more sensitive even in the 2h/day ozone treatment. Increased treatment time decreased photosynthesis and stomatal conductance. Chlorophyll fluorescence was not significantly different among treatment times. However, carboxylation efficiency decreased with increased treatment time, and L. tulipifera was more sensitive than P. orientalis. Chlorophyll content did not differ with species or treatment time. SOD activity response was greater in L. tulipifera than in P. orientalis, increasing to $131\%$ of pretreatment observations. Therefore it was concluded that L. tulipifera was more responsive and had lower ozone tolerance than P. orientalis.

• BMB Reports
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• v.43 no.9
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• pp.579-583
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• 2010

The adipocyte-derived hormone leptin regulates appetite and bone mass. Recent research demonstrates that reciprocally, osteoblasts have a role in controlling energy metabolism. Several genes expressed in osteoblasts are involved in this process, and one of them is the Esp gene. The remaining genes regulate Esp gene expression. OST-PTP, the protein name of Esp, regulates the carboxylation of osteocalcin secreted from osteoblasts, thus affecting insulin sensitivity and insulin secretion. This review provides evidence for a novel interpretation of the connection between bone and energy metabolism and expands our understanding of the novel physiology of bone beyond its classical functions.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.320-330
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• 2012

This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.

• Textile Coloration and Finishing
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• v.30 no.3
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• pp.168-179
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• 2018

The modified surface of specialty carbon black(SCB) is one of the main technical factors for producing a uniform color and stable dispersion. In this work, the carboxylation or sulfonation process of SCB was used to improve the dispersive properties of hydrophilic solvents such as 1,6-hexanediol and propylene glycol monomethyl ether acetate(PGMEA). The results showed that the color strength of SCB DC2500G changed little with a range of 0.128~0.941(${\Delta}E$) compared to other SCB DC2500G material. In contrast, in the case of SCB EG410, there was a uniform color value with a range of 0.144~0.252(${\Delta}E$). Also, in our experiments, a modified SCB was confirmed by printing ink material as a melt coating paper. It may be possible that the SCB EG410 material can be advantageous as a gravure ink product. Finally, the modified SCB obtained from this research will have a large impact on the industry as a potential material for toners, paint, rubber, fillers, and other carbon black additives.

• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.571-577
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• 2003

The intracellular metabolic fluxes can be calculated by metabolic flux analysis, which uses a stoichiometric model for the intracellulal reactions along with mass balances around the intracellular metabolites. In this study, metabolic flux analyses were carried out to estimate flux distributions for the maximum in silico yields of various metabolites in Escherichia coli. The maximum in silico yields of acetic acid and lactic acid were identical to their theoretical yields. On the other hand, the in silico yields of succinic acid and ethanol were only 83% and 6.5% of their theoretical yields, respectively. The lower in silico yield of succinic acid was found to be due to the insufficient reducing power. but this lower yield could be increased to its theoretical yield by supplying more reducing power. The maximum theoretical yield of ethanol could be achieved, when a reaction catalyzed by pyruvate decarboxylase was added in the metabolic network. Futhermore, optimal metabolic pathways for the production of various metabolites could be proposed, based on the results of metabolic flux analyses. In the case of succinic acid production, it was found that the pyruvate carboxylation pathway should be used for its optimal production in E. coli rather than the phosphoenolpyruvate carboxylation pathway.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.32-33
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• 1993

근래 환경 문제의 중요성이 크게 대두되면서 여러 제조 공정에서 방출되는 폐수등을 처리하는데 막분리 공정을 이용하려는 연구가 진행되고 있다. 이 공정에 필요한 내구성, 내 미생물성, 내 약품성등이 우수한 역삼투막 재료를 얻기 위한 방법의 하나로 엔지니어링 플라스틱을 친수화 시키는 방법이 개발되어 왔는데, 구체적으로는 설폰화등의 친수화가 된 폴리설폰(polysulfone), 폴리 에테르 에테르 케톤(poly ether ether ketone), 폴리 이미드(polyimide) 수지등이 검토되고 있다. 특히 PPO(poly(2,6-dimethyl-1,4-phenylene oxide))로 만들어진 분리막은 내산화성이 우수하고 내구성이 뛰어나다고 알려져 있다. 본 연구에서는 PPO를 유기 금속 반응을 이용하여 carboxylation시키고 이 carboxylated PPO로 역삼투막을 제조하여 투과특성을 조사하였다.

• Journal of Dairy Science and Biotechnology
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• v.29 no.1
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• pp.33-39
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• 2011

Vitamin K, which is a nutritional factor, play a role in the regulation of bone metabolism. Vitamin K exists naturally in 2 forms, namely, vitamin $K_1$ (phylloquinone) in green plants and vitamin $K_2$ (menaquinone) in animals and bacteria. Vitamin $K_1$ has an effect on bone metabolism. Vitamin $K_2$ is essential for the ${\gamma}$-carboxylation of osteocalcin, a bone matrix protein containing ${\gamma}$-carboxyglutamic acid (Gla) which is synthesized in osteoblast of bone tissues. This paper is to provide the basic information of vitamin K by supplying function and biological activity of vitamin K together with vitamin K producing lactic acid bacteria and it's utilization for the dairy products production.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.809-816
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• 2010

Microbial biotransformations can be used to predict mammalian drug metabolism. The present investigation deals with microbial biotransformation of valdecoxib using microbial cultures. Thirty-nine bacterial, fungal, and yeast cultures were used to elucidate the biotransformation pathway of valdecoxib. A number of microorganisms metabolized valdecoxib to various levels to yield nine metabolites, which were identified by HPLC-DAD and LC-MS-MS analyses. HPLC analysis of biotransformed products indicated that a majority of the metabolites are more polar than the substrate valdecoxib. Basing on LC-MS-MS analysis, the major metabolite was identified as a hydroxymethyl metabolite of valdecoxib, whereas the remaining metabolites were produced by carboxylation, demethylation, ring hydroxylation, N-acetylation, or a combination of these reactions. The hydroxymethyl and carboxylic acid metabolites were known to be produced in metabolism by mammals. From the results, it can be concluded that microbial cultures, particularly fungi, can be used to predict mammalian drug metabolism.