• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.598-606
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• 2003

Salmonella encodes an enterotoxin (Stn) which possesses biological activity similar to the cholera toxin. Stn contributes significantly to the overall virulence of S. typhimurium in a murine model. The production of Stn is enhanced in a high-osmolarity medium and by contact with epithelial cells. In the present study, the in vitro and in vivo transcriptional regulations of the sin promoter revealed two promoters, P1 and P2. The P1 promoter identified by a primer extension analysis of stn mRNA exhibited a switching mechanism in vivo. Depending on the growth stage, transcription was initiated from different start sites termed $P1_S\;and\;P1_E$. $P1_S$, recognized by RNA polymerase containing ${\sigma}^S(E{\sigma}^S),\;and\;P1_E$, recognized by $E{\sigma}^70$, were activated during the stationary and exponential phases, respectively, while $P1_S\;and\;P1_E$ were both negatively regulated by CRPㆍcAMP and H-NS. Results revealed that $P1_S$ was the responsible promoter activated under a high osmolarity and low pH. The P2 promoter was identified 45 nucleotides downstream from $P1_E$ and negatively controlled by CRPㆍcAMP in vitro. No P2 activity was detected in vivo. The regulation of stn expression monitored using a Pstn::egfp fusion indicated that $E{\sigma}^S$ was required for the induction of stn and various factors were involved in stn regulation inside animal cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.469-474
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• 2002

This study was conducted to investigate the effects of gamma irradiation on the shelf-life extension of semi-dried squid (Todarodes pacificus). Semi-dried squid was stored at 10$^{\circ}C$ after gamma irradiation with doses of 0, 3, 5 and 7 kGy. In microbiological aspects, non-irradiated semi-dried squid was rapidly deteriorated during storage, and molds and yeasts were detected in a selective medium. The total viable cells were reduced with the increase of irradiation dose, and a dose level of 7 kGy was considered optimum and effective dose for the preservation of semi-dried squid. Increase in the content of volatile basic nitrogen was reduced by irradiation treatment depending upon doses. Thiobarbituric acid values were not significantly different in all samples regardless of irradiation. Sensory qualities of irradiated semi-dried squid were acceptable.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.303-312
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• 1998

It is necessary to quantitatively asses the influence of tidal currents to analysis the coastal current patterns before or after constructing offshore structures like as breakwaters. This assesment can be made through the use of simulation models designed to reproduce the water movements of the area. And it is very important to predict a phenomenon of pollutant dispersion in the area. In this study, in order to predict the changes of sea water quality for the port development plan, Ilgwang harbour, located at the east coast of Pusan, the numerical computations were carried out. The flow patterns were investigated before and after the development of the harbour bay and coastal area connected on it. The computational models are an extension of earlier work on the flow which used the ADI Method (Alternating Direction Implicit Method) in appling to Osaka Bay by KANEKO et al. The transport of pollutant constituents depends upon the currental characteristics of the water-transporting medium. In the currental flow model, water velocities and water levels are computed throughout the regions of it. These value are then used in the mass-balance equation to obtain the pollutant-constituent transport. As a result of this research, the present water quality of Ilgwang harbour and the coastal areas connected on it was proved out some good condition. The changes of sea water quality due to the port development plan of the Ilgwang habour bay and the coastal area were not large compared with the present condition, but it will be likely able to get worse by increasing the semi-enclosed areas in the harbour bay. In order to improve the water quality of the area after development, the method to activate tidal exchange in the area can be needed, as a mitigation technique.

• Resources Recycling
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• v.25 no.1
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• pp.68-75
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• 2016

Realization of zero waste society, which includes reduction, recycling and reuse of waste, has been a huge issue in Korea recently, and many experts are proposing various improvement plans in the establishment of political system. In particular, the current EPR system is partially agreed on its external achievement, but many problems are arising from the enforcement of the system. Therefore, flexible revisions and modifications on recycling policy are necessary. In order to understand the insufficiency and problem of the expansion of items in current EPR system, this study examined the actual generation and basic unit in small, medium and large-scale apartment complexes in B City and predicted the items that do not appear in the statistics to compare and analyze the problems in current recycling based on their result value; a survey was conducted on 137 experts and students of relevant major that live in B City on the items of EPR system and their perceptions to indicate the error in the necessity of items in EPR system that are generally underperceived by people and the error of current recycling system, and solution plans were sought to establish smooth future system.

• Research in Plant Disease
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• v.9 no.1
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• pp.28-31
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• 2003

A sclerotinia rot was occurred on the stems of Obedient plant (Physostegia virginiaqna) grown in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services, Korea in 2002. The typical symptoms of the disease were that the infected leaves and stems, at first, became dark green, then watery and soft rotted, later, White fluffy mycelia formed on the lesion developed black sclerotia, later, Sclerotia formed on the plants and PDA medium were globose to cylindrical or irregular in shape and 1.0~10.3$\times$1.0~8.4 mm in size. Aphothecia were cup-shape with numerous asci and 0.8~1.8 cm in diameter, Asci were cylindrical in shape and 84~286$\times$4.7~26.3 ${\mu}{\textrm}{m}$ in size. Ascospores were one cell hyaline, ellipsoid to ovoid in shape, and 7.6~12.8$\times$3.4~6.2 ${\mu}{\textrm}{m}$ in size. The optimum temperature far mycelial growth was $25^{\circ}C$. This is the first report on the sclerotinia rot of Physostegia virginiaqna caused by Sclerotinia sclerotiorum in Korea.

• Research in Plant Disease
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• v.12 no.2
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• pp.122-124
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• 2006

Sclerotinia rot was occurred on the leaf and stem of Fatsia japonica in Geoje city, Gyeongnam province in Korea from 2004 to 2005. The typical symptom of the disease was water-soaked infected leaves and stems. The colony of the isolated fungus was white to faintly gray in color. Apothecia were cup-shaped with numerous asci and $0.8{\sim}1.3 cm$ in size. Asci were cylindrical in shape and $70{\sim}220{\times}4{\sim}18{\mu}m$ in size. Ascospores were aseptate, hyaline, ellipsoid in shape, and $6{\sim}12{\times}4{\sim}6{\mu}m$ in size. Sclerotia formed on the plants and PDA medium were globose to cylindrical or irregular in shape, black in color. The optimum temperature for mycelial growth was $25^{\circ}C$. This is the first report on the Sclerotinia rot of Fatsia japonica caused by Sclerotinia sclerotiorum in Korea.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1102-1106
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• 2000

This study was carried out to investigate the effects of gamma irradiation for the improvement of hygienic quality and the extension of shelf-life of Kwamegi(semi-dried colobabis seira). Kwamegi was stored at $5^{\circ}C$ and $15^{\circ}C$ after gamma irradiation with doses of 0, 3, 5, 7 and 10 kGy. In microbiological aspects, non-irradiated Kwamegi was rapidly deteriorated during storage, and some harmful bacteria were detected in a microbial analysis using a selective medium. However, the total viable cells and presumptive pathogens were reduced with the increase of irradiation dose, and dose level of 7 to 10 kGy was considered to be optimum and effective dose for the preservation of Kwamegi.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.194-196
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• 2009

A new standard carnation Dianthus caryophyllus 'Pink Beryl' was bred from a cross of red standard cultivar 'Francesco' and purple standard cultivar 'Saturn' in 1996 at the National Institute of Horticultural & Herbal Science. After investigation of the characteristics for 4 years from 1997 to 2000 and registered to the official breeding variety of Rural Development Administration in 2000. 'Pink Beryl' is pink standard cultivar with round edge of petal for cut flower. It has medium resistance to Fusarium wilt. To avoid calyx splitting caused by high temperature, this cultivar is recommended to grow over $8^{\circ}C$ at night and under $25^{\circ}C$ at days during flower bud differentiation period.

• Journal of Dairy Science and Biotechnology
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• v.36 no.4
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• pp.220-225
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• 2018

The purpose of this study was to investigate the effect of ultrasonic treatment during probiotics production process on the shelf life and the survival rate. Once Lactobacillus plantarum and Bifidobacterium longum were cultured in edible culture medium, ultrasonic treatment was performed at 100 Hz for 1, 2, 5, 7, and 10 minutes. Ultrasonic-treated L. plantarum HY7715 and B. longum HY8001 were centrifuged, mixed with a cryoprotectant, and lyophilized. The prepared lactic acid bacteria powder was individually packaged. After 6 months, viable cell counts were measured separately under cold storage and room temperature. In vitro digestion experiments were performed to determine the survival rate at digestive tract. As a result, it was observed that shelf life and survival rate were increased compared to untreated control group.

• Journal of Family Resource Management and Policy Review
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• v.26 no.1
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• pp.59-73
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• 2022

This qualitative study focused on the activation of cooperative child care sharing centers'. Eight centers nationwide were selected as example cases in accordance with region (large city, small and medium-sized city, county unit), opening time, operating institution, location, full-time care for dual-income children, and participation in the 2020 care community pilot project. Co-researchers visited each center together to observe the site and conducted in-depth interviews with the head of the center or dedicated staff using semi-structured questionnaires. Interview data were analyzed using triangle verification and transcribed : the data were then grouped into 12 categories and 34 subcategories. From this, the following three topics were derived: the main functions, operational difficulties, and activation conditions. In conclusion, four suggestions are made: 1. proper relationship with the Family center, the cooperative childcare sharing center, and the local care communities 2. activation plan through "solution of operational difficulties" 3. "extension" of the cooperative child care sharing center 4. the role of the Ministry of Gender Equality and Family, the Korea Institute for Healthy Family, local governments, and Family Centers.