• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.6
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• pp.101-108
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• 2003

Small-scale models have been frequently used for experimental evaluation of seismic performance because of limited testing facilities and economic reasons. However, there are not enough studies on similitude law for analogizing prototype structures accurately with small-scale models, although conventional similitude law based on geometry is not well consistent in the inelastic seismic behavior. When fabricating prototype and small-scale model of reinforced concrete structures by using the same material. added mass is demanded from a volumetric change and scale factor could be limited due to size of aggregate. Therefore, it is desirable that different material is used for small-scale models. Thus, a modified similitude law could be derived depending on geometric scale factor and equivalent modulus ratio. In this study, compressive strength tests are conducted to analyze equivalent modulus ratio of micro-concrete to normal-concrete. Equivalent modulus ratios are divided into multi phases, which are based on ultimate strain level. Therefore, an algorithm adaptable to the pseudodynamic test. considering equivalent multi-phase similitude law based on seismic damage levels, is developed. In addition, prior to the experiment. it is verified numerically if the algorithm is applicable to the pseudodynamic test.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.305-310
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• 2008

The volatile constituents of the fresh roots of Panax ginseng C.A. Meyer have been investigated after treatment with artificial saliva and analysed by gas chromatography-mass spectrometry (GC-MS) using solid phase microextraction (SPME) fiber. Twenty peaks were detected in fresh ginseng, 5 of them were unknown peak, and mainly hydrocarbon components (${\alpha}$-pinene, ${\beta}$-pinene, myrcene, limonene, ${\beta}$-panasinsene, ${\beta}$-elemene, ${\beta}$-gurjunene, trans-caryophyllene, ${\alpha}$-gurjunene, ${\alpha}$-panasinsene, ${\alpha}$-neoclovene, trans-${\beta}$-farnasene, ${\alpha}$-humulene, ${\beta}$-neoclovene, ${\alpha}$-selinene, ${\beta}$-selinene, bicyclogermacrene) were detected. It's area percentage was increased about 10% in the fresh ginseng added artificial saliva during 40 minutes.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.419-424
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• 2018

In this work, effect of the culture medium composition on the fermentation process of Clostridium ljungdahlii, which is acetogenic bacteria to product ethanol from synthesis gas, was examined to improve the microbial growth and ethanol production. Components of the culture medium such as yeast extract, fructose, $NH_4Cl$, and $K_2HPO_4$ were selected as influence factors for the cell growth and ethanol production. As the concentration of yeast extract increased, both of the cell growth and ethanol production increased. And the ethanol productivity was the highest at an yeast extract of 0.05 g/L, which is lower than that of base medium. As the concentration of fructose increased, the cell growth increased, but the ethanol production decreased when the concentration of fructose was higher than that of base medium (5 g/L). In an experiment with the yeast extract of 5 g/L, produced ethanol concentration was the highest (0.297 g/L) when fructose concentration was 5 g/L, however, the specific ethanol productivity was higher (0.281 g/g DCW) when the fructose was not added due to very low cell mass. The cell growth and ethanol production were not significantly influenced by $NH_4Cl$ concentration, however the growth inhibition was observed at a 30 g/L of $NH_4Cl$. When the concentration of $K_2HPO_4$ increased, both of the cell growth and ethanol production increased. In experiments with $NH_4Cl$ and $K_2HPO_4$, specific ethanol productivities were higher when the low concentration of yeast extract was used.

• Journal of Plant Biotechnology
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• v.47 no.3
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• pp.242-247
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• 2020

This experiment was performed to determine the concentration of coconut water that is most effective in promoting the growth of 'Maehyang' strawberry in tissue culture. Cultivars in this experiment consisted of 'Maehyang' grown in the presence of 0, 20, 40, 60, 80, 100 ml·L^-1 of coconut water which was added to a medium mixed with BA 0.5 mg·L^-1 and IBA 0.1 mg·L^-1. Morphological variation tests and SSR detection with coconut water were conducted to determine variations in proliferation. The proliferation rate of 'Maehyang' strawberry improved with the coconut water treatment compared to non-treatment. In particular, the proliferation rate with 100 ml·L^-1 coconut water treatment increased by about 4 times. When 'Maeyang' was treated with 100 ml·L^-1 of coconut water, two morphological variants occurred without genetic variation. Therefore, the results suggest that 100 ml·L^-1 of coconut water can be used to mass-produce "Maeyang" strawberry without causing genetic variations.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.25-34
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• 1999

The effects of copper on the anaerobic degradation of propionate were studied using anaerobic batch reactors. The apparent inhibitory effects of copper on the anaerobic degradation of propionate could be observed from behaviors of intermediates, ultimate methane yield(UMY) and specific methanogenic activity(SMA) There was little inhibition at the concentration of $2.5mg\;Cu^{2+}/L$. Beyond this concentration, the inhibitory effects increased with increasing dose of coppers. The 50% inhibition of UMY and SMA occurred at copper dosage of 33.8 and $24.1mg\;Cu^{2+}/gVSS$, respectively. The inhibitory effect based on the UMY was gradually reduced with the operation time dueprobably to the acclimation of microorganisms and/or binding of the added copper by ligands(and possibly ion exchange sites)contained on the cell membrane and extracellular polymer matrix whereas it based on the SMA might exclude the this phenomena. Therefore, the methodology for interpretation of inhibition data based on the SMA was more accurated than the UMY. There was no inhibitory effect in batch reactors supplemented with sulfate due to an antagonistic action of the sulfate reducing bacteria. Propionate degradation was initially retarded for copper inhibited samples but it gradually degraded afterward. Based on the mass removal considering take into account the propionate to acetate conversion, propionate degradation may appeal more affected than acetate. This result revealed that the hydrogenotrophic methanogens were the most affected by copper.

• Membrane Journal
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• v.30 no.5
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• pp.319-325
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• 2020

In this study, we developed mixed matrix membranes by blending thermoplastic elastomer, i.e. polystyreneblock-polybutadiene-block-polystyrene (SBS) block copolymer with the synthesized UiO-66 particles for CO₂/N₂ gas separation. To investigate the effect of UiO-66 particles in the SBS matrix, we prepared different mixed matrix membranes (MMMs) by varying the mass ratio of SBS and UiO-66 in the blend. To fabricate well-dispersed UiO-66, the SBS/UiO-66 mixture was sonicated and stirred thoroughly. The physico-chemical properties of prepared membranes were characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The gas separation performance was measured by time-lag method. The permeability of the MMMs increased significantly as the content of UiO-66 increased, but the CO₂/N₂ selectivity did not decrease significantly. The membranes containing 20% of UiO-66 particles showed the best performance with the CO₂ permeability and CO₂/N₂ selectivity of 663.8 barrer and 13.3, respectively. This result showed performance closer to upper bound than pure SBS membrane in the Robeson plot, as the added UiO-66 particles did not significantly sacrifice selectivity and more than doubled gas permeability.

• KSBB Journal
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• v.19 no.1
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• pp.17-26
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• 2004

In this study the extracellular production of 5-aminolevulinic aicd (ALA) by recombinant E. coli BL2l (DE3) pLysS harboring the plasmid pFLS45 are investigated. Optimum concentrations of succinic acid and glycine for cell growth and ALA production were found to be 30 mM and 15 mM, respectively. Levulinic acid (LA) as an inhibitor of ALAD was added to the culture medium in the end of exponential cell growth phase and its optimum concentration was 30 mM. Growth of recombinant E. coli BL2l (DE3) pLysS (pFLS45) was largely dependent upon the pH value of culture medium. When the pH of culture medium was in the range of 6.0 and 6.5, high cell mass and ALA production were obtained. IPTG induction for the expression of the fusion gene did not enhance the production of ALA. Recombinant cell grew at 30't faster than at 37$^{\circ}C$, but ALA productivity was lower than at 37$^{\circ}C$. Repeated addition of glycine, succinic acid, and LA increased the production of ALA and the inhibition of intracellular ALA dehydratase activity, with up to 1.3 g/L ALA having been produced in the cultivation.

• The Journal of Pediatrics of Korean Medicine
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• v.20 no.2
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• pp.177-196
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• 2006

Objective : This experimental study was designed to determine the effects of BPT on obesity in vivo and in vitro. Methods : in vitro, BPTn extracts of various concentration(50, 100, 200 ${\mu}g/m{\ell}$) were added in 3T3-L1 cell. Adipocyte differentiation was measured by Oil Red O staining and Morphological examination. The expression of $C/EBP{\alpha}$ and $PPAR{\gamma}$ receptor was measured by western blot assay and RT-PCR in vivo, Rats were orally administered BPT daily for consecutive four weeks before poloxamer-407 induced hyperlipidemic state. The rats were sacrificed 24 hrs later for poloxamer-407 treated and then serum triglyceride, total cholesterol were measured ; Rats were orally administered BPT daily for consecutive four weeks before triton WR-1339 induced hyperlipidemic state. The rats were sacrificed 40 hrs later for triton WR-1339 treated and then serum triglyceride, total cholesterol were measured ; Rats with obesity were induced by the high fat-diet for six weeks and then serum triglyceride, total cholesterol, LDL-cholesterol, triglyceride, HDL-cholesterol, hydroxy radical, superoxide dismuatse activity were measured. Results : In vitro, The 3T3-L1 cells' differentiation was significantly decreased by BPT. The expression of $C/EBP{\alpha}$ and $C/EBP{\beta}$ was decreased by BPT. In vivo, BPT significantly reduced serum triglyceride, total cholesterol contents in poloxamer-407 treated rat. BPT significantly reduced serum triglyceride contents in Triton WR-1339 treated rat. Total cholesterol also reduced but did not show a significant change. BPT significantly reduced body weight gain of rat and adipose tissue mass of rats and serum triglyceride, LDL-cholesterol contents and significantly increased HDL-cholesterol, HTR(HDL-cholesterol/Total-cholesterol) in rats with obesity induced by the high fat-diet. BPT reduced blood lipid peroxide, hydroxy radical and increased superoxide dismuatse(SOD) activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.563-570
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• 1985

The main purpose of this study is to evaluate a revolving plate-type biofilter system for mass culture of eels (Anguilla japonica) based on the experimental rearing for 199 days. Water quality, growth efficiency of fish and effects of fish disease control were critically evaluated. The experiment was conducted in two different units, each unit consisting of a cement tank containing $20m^3$ of water. In unit A, a biofilter which includes 400 rotating undulated P. V. C. plates being 70 cm in diameter which rotates at 6 rpm and also 400 undulated P. V. C. plates fixed in the settling chamber of an area of $66{\times}62cm$. Water was continuously passed through the filter at a rate of 260 l/min., and supplemental water was added to the fish tank at a rate of $4m^3$ a day. In unit B, the biofilter has 400 P. V. C. plates being $66{\times}62cm$ each was installed in the settling tank. The results gained from the experimental rearing for 199 days from April 21, 1984 to November 5, 1984 are as follows. In the growth experiment, the weight of fish in unit A increased from 3.0 kg to 815.6 kg, while in unit B, from 3.0kg to 416.0kg. During the period of the experiment, in the both units the fish grew at an acceptable rate at the temperature at which they were held. Observing every aspect of eel culture, including growth rate, disease control and water quality, unit A appears to have adventages over unit B, which makes it particuraly attractive in intensive recirculating fish culture system. It was further observed that certain parasites such as Trichodina sp. and Costia sp. could easily be controled by appling 4 ppm of $KMNO_4$.

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.42-48
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• 2011

Chloroplast genetic engineering of higher plants offers several unique advantages compared with nuclear genome transformation, such as high levels of transgene expression, a lack of position effect due to site-specific transgene integration by homologous recombination, multigene engineering in a single transformation event and reducing risks of gene flow via pollen due to maternal inheritance. We established a reproducible chloroplast transformation system of potato using a tobacco specific plastid transformation vector, pCtVG (trnI-Prrn-aadA-mgfp-TpsbA-trnA). Stable transgene integration into chloroplast genomes and the homoplasmic state of the transgenome were confirmed by PCR and Southern blot analyses. Northern, immunoblot analysis, and GFP fluorescence imaging revealed high expression and accumulation of GFP in the plastids of potato leaves. This system would provide new opportunities for genetic improvement and mass production of value added foreign proteins in this crop.