• Korean Journal of Materials Research
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• v.20 no.8
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• pp.418-422
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• 2010

As a starting material, BCP (biphasic calcium phosphate) nano powder was synthesized by a hydrothermal microwave-assisted process. A highly porous BCP scaffold was fabricated by the sponge replica method using 60 ppi (pore per inch) of polyurethane sponge. The BCP scaffold had interconnected pores ranging from $100\;{\mu}m$ to $1000\;{\mu}m$, which were similar to natural cancellous bone. To realize the antibacterial property, a microwave-assisted nano Ag spot coating process was used. The morphology and distribution of nano Ag particles were different depending on the coating conditions, such as concentration of the $AgNO_3$ solution, microwave irradiation times, etc. With an increased microwave irradiation time, the amount of coated nano Ag particles increased. The surface of the BCP scaffold was totally covered with nano Ag particles homogeneously at 20 seconds of microwave irradiation time when 0.6 g of $AgNO_3$ was used. With an increased amount of $AgNO_3$ and irradiation time, the size of the coated particles increased. Antibacterial activities of the solution extracted from the Ag-coated BCP scaffold were examined against gram-negative (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). When 0.6 g of $AgNO_3$ was used for coating the Ag-coated scaffold, it showed higher antibacterial activities than that of the Ag-coated scaffold using 0.8 g of $AgNO_3$.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.210-213
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• 2005

The suppression of apoptosis during the cell culture might increase recombinant protein production. In the present study, the effects of anti-apoptotic agents on the apoptosis of recombinant Chinese Hamster Ovary cells and the production of Iduronate 2-sulphatase(IDS) were investigated Cell density slightly increased when $2{\mu}M$ of EGCG and $10{\mu}g/mL$ of STR-G were added to culture medium after two days. It was observed that the percentage of apoptotic cells was decreased in the culture with STR-G, and Bcl-2 expression level was enhanced in both culture with STR-G and EGCG. These results suggest that G418 and EGCG are effective anti-apoptotic agents for increasing the productivity of IDS with recombinant CHO-DG44.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.28-35
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• 2008

Several extracts of different parts and solvent fractions of Cornus kousa were obtained and their functional material contents, antioxidant activities and tyrosinase inhibition effects were determined. Content of total polyphenols and flavonoids contents in flower were 169.638 $mg{\cdot}g^{-1}$ and 25.418 $mg{\cdot}g^{-1}$, respectively, which were much higher than those of other parts. Also, flower extracts showed the strongest effects on DPPH and ABTS radicals scavenging and ferrous ion chelating. In flower, leaf, and stem extracts, inhibition effects on peroxidation of linoleic acid determined by ferric thiocyanate(FTC) method were higher than a synthetic antioxidant, BHT. Tyrosinase inhibition activities were shown only in flower extract. Flower and leaf extracts, showing high biological activities in various system, were successively reextracted with n-hexane, chloroform, ethylacetate and n-butanol. Total polyphenol contents of water fractions were higher than any other solvent fractions in both flower and leaf, 67.006 $mg{\cdot}g^{-1}$ and 67.739 $mg{\cdot}g^{-1}$, respectively. But total flavonoid contents were higher in ethyl acetate fraction for flower extract and butanol fraction for leaf extract. Among the solvent fractions, the highest efficiency of free radical scavenging activities was obtained in ethyl acetate fraction for flower extract and n-butanol fraction for leaf extract. Tyrosinase inhibition activities were higher in water fraction for both flower and leaf extracts, 49.24% and 31.8%, respectively.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.302-309
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• 2013

The highly porous cellulosic aerogels were prepared by freeze-drying method using sodium hydroxide-urea aqueous solution in the process of dissolution, gelation, regeneration and organic solvent substitution. The structural characteristics of porous aerogel were analyzed using scanning electron microscopy and nitrogen adsorption apparatus. As a result, the dissolving pulp was completely dissolved, but filter papers and holocellulose were divided into two layers (dissolved and undissolved parts) in the process of centrifugation. The structure of aerogel from dissolved pulp showed porous pores in the surface and net-shaped network in the inner part. Aerogels from filter paper and holocellulose had the condensed porous network surface and the open-pore nano-fibril network inner structure. Undissolved form of fibers was observed in the aqueous solution of aerogel from holocellulose. The BET value ($S_{BET}$) of aerogel from dissolved pulp was ranged in 260~326 $m^2/g$, and it was decreased with the increase of concentration. Whereas, the $S_{BET}$ value of aerogel from filter paper (198~418 $m^2/g$) was increased with the increase of concentration. The $S_{BET}$ value of aerogel from holocellulose were 137 $m^2/g$ at 2% (w/w) of cellulose, and it was increased to maximum 401 $m^2/g$ at 4% (w/w) of cellulose. Then, it was decreased at 5% (w/w) of cellulose.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.119-134
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• 2013

Species composition, abundance and seasonal variation of the fish community in the water off Hwaseong City, the West Sea, Korea were determined using monthly samples collected by a stow net from March 2011 to February 2012. A total of 71 species, 608,801 individuals and 795,503.3 g of fish were collected during the study. Dominant species were Engraulis japonicus accounting for 97.3% (592,926 individuals) in total number of individuals and 78.2% (622,815.8 g) in total biomass. The other major species were Pholis fangi, Chaeturichthys stigmatias, Konosirus punctatus, Hyporhamphus intermedius, Amblychaeturichthys hexanema, Liparis tanakai, Pleuronectes yokohamae and Okamejei kenojei. Fish collected were 59 species, 190,406 individuals and 241,113.4 g in the surface stow net and 61 species, 418,395 individuals and 554,389.9 g in the bottom stow net. Catch rate was low from March to May although the number of species was high. Catch rate significantly increased from June, but the number of species was relatively low.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.418-421
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• 2001

The gellan was produced by Pseudomonas elodea ATCC 31461 under aerobic condition. Gellan provides various functionalities such as gelling, suspending, stabilizing, emulsifying and binding properties in aqueous systems. In this study, the effect of glucose concentration and nitrogen sources concentration, bacto peptone and $NH_4NO_3$, on the cell growth and the production of gellan were evaluated. The maximum specific yield (g gellan/g cell) of 2.22 was obtained at 1.0% of glucose. Bacto peptone increased cell growth. And nitrogen limitation was essential for higher production of gellan. The highest cell and gellan production were abtained at 0.5 g/${\ell}$ of bacto peptone without $NH_4NO_3$.

• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.409-418
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• 2016

Objectives: The purpose of this study was to characterize penicillin G resistant bacteria in surface water from pharmaceutical complex effluent. Methods: Surface water was sampled from pharmaceutical complex effluent in Gyeonggi-do Province, Korea in March 2015. Water samples were plated in triplicate on tryptic soy agar plates with 32 mg/L of penicillin G. Penicillin G resistant bacteria were selected from the effluent and subjected to 16S rRNA analysis for the penicillin G resistant species determination. Identified resistant strains were tested for resistance to various antibiotics. Results: Penicillin G resistant bacteria were present at 8.0% in terms of culturable heterotrophic bacteria. Identified penicillin G resistant bacteria exhibited resistance to more than nine of the antibiotics studied. These resistant bacteria are gram negative and are closely related to pathogenic species. Conclusion: Multi-antibiotic resistant bacteria in the surface water of pharmaceutical complex effluent suggest the need for disinfection and advanced oxidation processed for pharmaceutical effluent.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.418.3-419
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• 2002

Enalapril. a prodrug. is the ethyl ester of a long-acting angiotensin converting enzyme inhibitor. enalaprilat. Because enalapril does not contain any appreciable chromophore. detection of the drug in a complex matrix (e.g.. biological fluids) has been problematic with conventional detection systems in high-performance liquid chromatography (HPLC). As a result. determination of enalaprillevel in blood samples has been typically carried out using HPLC-MS/MS in the literature. (omitted)

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.413-418
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• 1996

To derive the optimimum antenna launching condition for fast wave current drive, the propagation and absorption of the ion cyclotron range of frequencies waves are studied in a KT-2 tokamak plasma. We sove the kinetic wave equation in one dimensional slab geometry with the phase-shifted antenna array to inject the toroidal momentum to electrons. The accessibility conditions and the guidelines of the optimum antenna design for the efficient current drive are derived. The dependence of the current drive efficiency on launching conditions such as the phase and spacing Is presented.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.125-130
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• 1997

Separating the patient from hypothermic cardiopulmonary bypass(CPB) before achieving adequate rewarming often results in afterdrop, which can predispose to electrolyte disturbances, arrhythmia, hemodynamic alterations, and shivering-induced increase of oxygen consumption. In an attempt to find an adequate end point temperature of rewarming after hypothermic CPB, 50 pediatric cardiac surgical patients were r ndomly assigned for end point temperature of rewarming of 35.5$^{\circ}C$ (Group 1) or 37t (Group 2), rectal temperature. Thereafter the rectal temperature was measured half, one, four, eight, and 16 hour after arrival to the intensive care unit(ICU), with heart rate and blood pressure. Additionally the rectal temperature was compared with esophageal temperature during CPB, and axillary temperature luring stay in the ICU. Nonpulsatile perfusion with a roller pump was used in all patients and a membrane or bubble oxygenator was used for oxygenation. Both groups were comparable with respect to age, sex, body surface area, total bypass time, and rewarming time. There was no afterdrop in both groups, and there were no statistical differences in the rectal temperatures between two groups. There were also no statistical dilyerences with respect to the heart rate and blood pressure between two groups. At the end of rewarming the esophageal temperature was higher than the rectal temperature. The axil ary temperature measured in ICU was always lower than the rectal temperature. No shivering was noted in all patients. In conclusion, with restoration of rectal temperature above 35.5$^{\circ}C$ at the end of CPB in pediatric patients, we did not observe an afterdrop.