• Korean Journal of Microbiology
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• v.42 no.1
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• pp.40-46
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• 2006

Galactose joined to glucose by a $\beta(1\rightarrow4)$ glycosidic bond makes lactose and this disaccharide is rich in milk. It is known that lacotse is hydrolyzed to each monomeric sugar by either lactase in human or $\beta-galactosidase$ in bacteria. Ingestion of milk by lactase-deficient persons causes a temporary diarrhea and subsequent chronic diarrhea results in colitis with chronic inflammation. We isolated a $\beta-galactosidase$ producing psycrotolerant strain AS-20 from near cattle shed and investigated the growth at various temperature conditions. Whereas Escherichia coli strains did not grow at $10^{\circ}C$, the AS-20 strain could grow well at this low temperature and showed optimal growth at $30^{\circ}C$. The isolated strain was identified as 97% Hafnia alvei by biochemical properties. This strain could ferment glucose, lacotse, maltose, mannitol, xylose, ONPG, rhamanose and L-arabinose, and decarboxylate lysin and ornithine. To confirm the identity of isolated strain we amplified 16S rDNA by PCR and searched similarity of the 1426 bp DNA sequcence with Genbank database. The strain AS-20 showed 99% similarity with Hafnia alvei. The activity of $\beta-galactosidase$ was 1.5 times higher when the cell was grown at 10 or $20^{\circ}C$ than at $30^{\circ}C$. The highest enzyme activity of AS-20 was also much higher than that of E. coli, which was grown at $30^{\circ}C$.

• Journal of the Korean GEO-environmental Society
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• v.19 no.10
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• pp.13-19
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• 2018

Following the 2016 Gyeongju earthquake, the Pohang Earthquake occurred in 2017, and the south-east region in Korea is under the threat of an earthquake. Especially, in the Pohang Earthquake, the liquefaction phenomenon occurred in the sedimentation area of the coast, and preparation of countermeasures is very important. The soil liquefaction can affect the underground facilities directly as well as various structures on the ground. Therefore, it is necessary to identify the liquefaction risk of facilities and the structures against the possible earthquakes and to prepare countermeasures to minimize them. In this study, we investigated the seismic liquefaction risk about the electric power utility tunnels in the southeast area where the earthquake occurred in Korea recently. In the analysis of seismic liquefaction risk, the earthquake with return period 1000 years and liquefaction potential index are used. The liquefaction risk analysis was conducted in two stages. In the first stage, the liquefaction risk was analyzed by calculating the liquefaction potential index using the ground survey data of the location of electric power utility tunnels in the southeast region. At that time, the seismic amplification in soil layer was considered by soil amplification factor according to the soil classification. In the second stage, the liquefaction risk analysis based on the site response analyses inputted 3 earthquake records were performed for the locations determined to be dangerous from the first step analysis, and the final liquefaction potential index was recalculated. In the analysis, the site investigation data were used from the National Geotechnical Information DB Center. Finally, it can be found that the proposed two stage assessments for liquefaction risk that the macro assessment of liquefaction risk for the underground facilities including the electric power utility tunnel in Korea is carried out at the first stage, and the second risk assessment is performed again with site response analysis for the dangerous regions of the first stage assessment is reasonable and effective.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.748-756
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• 2009

The key for cultivating Lentinula edodes in sawdust bags with an appropriate strain and medium is to encourage the mushroom growth, while discouraging contaminating fungi by controlling environment, especially temperature and relative humidity (RH). To investigate the daily and seasonal fluctuation of temperature and RH in two L. edodes cultivation sheds types, HOBO data loggers was set and the collected data were analyzed. In a Taiwan type L. edodes cultivation shed, temperature and humidity changes were divided into five characteristic periods: mycelium growing winter, mushroom fruiting spring, mushroom fruiting early summer, mushroom nonfruiting summer and mushroom fruiting autumn. First, the mycelium growing winter was December to early March with daily mean temperature of $-1{\sim}8^{\circ}C$. Second, mushroom fruiting spring was mid March to late May with daily mean temperature of $8{\sim}21^{\circ}C$ and day-night temperature difference of $15^{\circ}C$. Third, the Mushroom fruiting early summer was early June to early July with 17 to $25^{\circ}C$. Fourth, nonfruiting summer was mid July to mid August with daily mean temperature of $25{\sim}28^{\circ}C$. Lastly, mushroom fruiting autumn was late August to October with daily mean temperature of $10{\sim}23^{\circ}C$ and with cyclic temperature change by $7^{\circ}C$ decrease and 5 increase every 5 to 7 days. In a Chinese type shed, temperature ranged $-1.9{\sim}5.0^{\circ}C$ during winter and $15{\sim}32^{\circ}C$ during June to October. Temperature and relative humidity changed $12{\sim}30^{\circ}C$ and 40~100%, respectively, depending on 0~150 cm shelf heights of by positions in the shed. In conclusion, to grow L. edodes but to discourage contaminating fungi, that is, not to be too high in temperature and RH, the growers changed temperature and RH by adjusting shading, aeration and insulation in the shed.

• Korean Journal of Acupuncture
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• v.33 no.2
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• pp.67-74
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• 2016

Objectives : The Knee degenerative osteoarthritis patients are not satisfied with the conventional therapies of KDOA, which results in the use of alternative therapies. The miniscalpel acupuncture is effective in treating chronic soft tissue, releasing contractures. However, there is little scientific evidence supporting the use of miniscalpel acupuncture in knee degenerative osteoarthritis. This study was designed to obtain basic data for a further large-scale trial as well as provide information about the feasibility of miniscalpel acupuncture in knee degenerative osteoarthritis patients. Methods : We describe the protocol for a randomized controlled pilot clinical trial of 5 weeks duration. Twenty patients will be recruited and randomly allocated to two treatment groups: miniscalpel acupuncture treatment(experimental group); and acupuncture and electro-acupuncture treatment(control group). Miniscalpel acupuncture will be performed once with a 1-week interval for 3 weeks. Electro-acupuncture will be administered twice per week for a period of 3 weeks. The primary outcomes will be measured by visual analogue scale and range of motion. The secondary outcomes will be short-form McGill Pain Questionnaire and Western Ontario and McMaster Universities Osteoarthritis Index. Both primary and secondary outcomes will be measured at baseline and at 1, 2, 3 and 5 weeks(i.e. 2 weeks after treatment completion). Conclusions : This pilot study will provide a basic foundation for a future large-scale trial as well as information about the feasibility of miniscalpel acupuncture in knee degenerative osteoarthritis.