• The Korean Journal of Mycology
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• v.18 no.2
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• pp.77-83
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• 1990

Factors influencing the fusion frequency of protoplasts were investigated with auxotrophic mutants of Pleurotus florida and Pleurotus ostreatus. Immediately after the polyethylene glycol (PEG) solution was added, the protoplasts adhered firmly and shrank. During the subsequent dilution with 0.6 M sucrose, the protoplasts regained their normal size and larger bodies were observed. Interspecific heterokaryons were obtained by fusion of the nutritionally complementing protoplasts. Hyphae of the heterokaryotic fusants formed true clamp connections. The optimum conditions were a total of 1 to 15 million protoplasts per ml, 30% polyethylene glycol 8000 solution with adjustment to pH 8.0 and 0.6 M sucrose stabilized regeneration medium. Other parameters such as $CA^{++}$, glycine, exposure time and temperature influenced mainly the viability of the protoplasts.

• 한국가시화정보학회:학술대회논문집
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• 2007.11a
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• pp.77-83
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• 2007

This paper presents numerical and experimental works for simultaneous pumping and mixing small liquid using asymmetric microelectrode arrays, based on AC electroosmotic flows. To this end, four arrangements of electrode pairs were considered with diagonal/herringbone shapes. Numerical simulations were made of three-dimensional geometries by using the linear theory. The results indicated that the helical flow motions induced by the electrode arrays play a significant role in the mixing enhancement. The pumping performance was influenced by the slip velocity at the center region of the channel compared to that near the side walls. To validate the numerical predictions, the microfluidic devices were made through MEMS. The flow rate was obtained by using micro PIV, increasing the applied frequency. The electrolyte was potassium chloride solution. The flow patterns above electrodes were visualized to see lateral flow for mixing. The experimental results showed good agreements with the numerical predictions.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.21-23
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• 1994

무방류폐수처리 시스템 개발에 막분리공정이 핵심적인 기술로 자리잡고 있다. 그러나 막분리기술의 경제성을 높히고 적용범위를 확대하기 위해서는 새로운 막의 개발과 폐수처리에서 항상 문제가 되는 fouling의 원인규명 및 막세척방법의 개발이 절실히 요구되고 있다. 본 연구에서는 염료폐수처리 및 재활용을 위한 pilot 실험에의 막의 fouling 현상과 세척효과를 역삼투막인 BW-30(2540)과 Nanofiltration막인 NF-40(2540) 모듈을 사용하여 조사하였다. RO 투과수에 의한 물리적 세척법인 flushing과 화학적세척을 실시하여 투과율 회복능력을 조사하였다.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2544-2547
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• 2008

A micro channel heat sink has been studied and optimized for mixed pressure driven and electroosmotic flows through three-dimensional numerical analysis. The effects of ionic concentration represented by zeta potential and Debye thickness are studied with the various steps of externally applied electric potential. Optimization of the micro channel heat sink has been performed considering two design variables related to the micro channel width, depth and fin width. The surrogate-based optimization is performed using a search algorithm taking overall thermal resistance as objective function. The thermal resistance is found to be more sensitive to channel width-to-depth ratio than fin width-to-depth of channel ratio.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.881-885
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• 2005

Purpose : Airway dehydration and subsequent hyperosmolarity of periciliary fluid are considered critical events in exercise-induced bronchoconstriction. The aim of this study was to establish if a hyperosmolar challenge could induce activation of eosinophils. Methods : Human eosinophilic leukaemic cell lines, EoL-1 cells were incubated with hyperosmolar solutions for 15 minutes. Activation of EoL-1 cells was monitored by degranulation and superoxide anion production. In addition, we examined surface expression of CD69 and ICAM-1. Results : Hyperosmolar stimuli didn't induce superoxide anion production and degranulation. In addition, EoL-1 cells cultured with hyperosmolar medium at 930 mOsm/kg $H_2O$ resulted in no significant increment in fluorescent intensity of CD69 and ICAM-1 expression compared with results for cells incubated with isomolar medium. Conclusion : We found that hyperosmolar stimuli don't cause activation of EoL-1 cells, but further studies are required to determine the role of eosinophil in the mechanism of exercise-induced asthma.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.167-169
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• 2011

The Saccharomyces cerevisiae S288c strain does not show haploid and diploid filamentous growth, and biofilm formation, because it has a flo8 nonsense mutation unlike ${\Sigma}1278b$ strain which has a FLO8 gene. During the heat stress experiments to investigate the role of ScKns1, LAMMER kinase in S. cerevisiae, we found that ${\Sigma}1278b$ strain revealed heat sensitivity at $37^{\circ}C$, a mild heat stress in contrast to S288c strain. We also found that the disruption of ScKns1 and the addition of sorbitol suppress heat sensitivity of ${\Sigma}1278b$ strain. These results suggest the possibility that Flo8 and ScKns1 may interact to transducer a signal for regulating heat stress through a novel signaling pathway.

• Food Science and Preservation
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• v.16 no.5
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• pp.759-764
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• 2009

The antimicrobial activities of extracts of Prunus mume by sugar against food poisoning bacteria, and the effects of heat and pH treatment on these antimicrobial activities, were investigated. The level of total solids, pH, and acidity of P. mume extracts were 55.08% (w/w), pH 3.1, and 1.52%, respectively. P. mume extracts showed the strongest antimicrobial activity against Vibrio parahaemolyticus, among the bacteria tested. P. mume extracts significantly inhibited the growth of V. parahaemolyticus, Bacillus cereus, and Staphylococcus aureus at levels of 1-2% (w/v) of extracts in media. The antimicrobial activities of P. mume extracts were neither affected by heating at $65-125^{\circ}C$ for 30 minutes, nor by neutralization of extract to pH 7.0.

• Food Science and Preservation
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• v.17 no.5
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• pp.706-711
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• 2010

Paeonia lactiflora Pall. was extracted with water and the Paeonia lactiflora Pall. extract (PLE) was tested for antimicrobial activities against Corynebacterium xerosis, Candida albicans, Listeria monocytogenes and Pseudomonas syringae. PLE showed pronounced antimicrobial effects at concentrations at or above 50 ${\mu}g$/mL. The activities were stable at $100^{\circ}C$ and over the pH range of 3-11. PLE may serve as a natural antimicrobial agent in food preservation. It is suggested that hydrophillic components in the extract synergistically perturb microbial membrane functions.

• The Korean Journal of Mycology
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• v.14 no.3
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• pp.215-223
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• 1986

Protoplasts of P. cornucopiae were reverted to normal hyphal growth and reversion frequency was $0.04{\sim}19%$. The complete medium stabilized with 0.6 M sucrose was most effective for regeneration of protoplasts. When hypertonic mushroom complete medium not containing agar was overlaid, regeneration frequency of protoplasts was the highest rate among the others of topagar. The protoplast reversion frequency and mycelial growth of P. cornucopiae were increased when various amino acids, nucleic acid components and vitamin compound were added to the hypertonic minimal medium. The relation between sources increasing reversion frequency and sources accelerating mycelial growth was similar in amino acids and nucleic acid components but it was different in vitamins. The protoplast reversion frequency showed the highest rate when all sources were added to the regeneration minimal medium. Microscopically, regeneration patterns of protoplasts showed formation of a bud-like structure, direct germination, yeast-like cell chain of the protoplast, and the production of both direct germ tube and yeast-like cell chain from a protoplast.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.275-280
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• 1998

Factors affecting protoplasts isolation and regeneration of Fomitella fraxinea were investigated. Lytic enzyme mixture of Novozym 234, Cellulase onozuka R-10 and ${\beta}-Glucuronidase$ was found to be the best for the protoplasts isolation. Osmotic stabilizer of 0.6 M sucrose was observed as the best for protoplasts isolation. The highest number of protoplasts was obtained from the F. fraxinea mycelium with lytic enzyme mixture and osmotic stabilizer that had been cultured for 3 hours. The highest regeneration rate of 0.02 % was achieved when the 0.6 M sorbitol was employed as osmotic stabilizer.