• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.96-104
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• 2013

Staphylococcus aureus is a major human pathogen that produces a wide array of toxins, leading to a number of adverse symptoms. We examined 275 strains of Staphylococcus aureus isolated from various foods between 2006 and 2008 for antimicrobial susceptibility. At least 259 (94.2%) of the tested strains showed antibiotic resistant properties, and 106 (40.7%) of them showed multiple antibiotic resistance. Eleven of the tested strains were resistant to oxacillin and mec A-positive. Moreover, oxacillin-resistant strains were significantly more likely to be multi-drug resistant (p < 0.01). Of the 275 isolates tested, 24.4% were noted as being positive for slime production and 30.5% were positive for biofilm assay. Antibiotic resistance was not associated with a significantly higher prevalence of biofilm formation. Twenty strains were classified using the DiversiLab system. Most of the strains could be classified into 2 clusters and 4 unique types. All 10 mec A-positive strains (cluster I) were grouped together into the same sub-cluster. Cluster II (6 strains) was not found to be resistant to oxacillin in this study. Although the prevalence of methicillin-resistant S. aureus in food is currently low, the risk of its transmission through the food chain cannot be disregarded.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.154-160
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• 2005

To establish rapid micropropagation through organogenesis from apices-derived callus or direct adventitious shoot of three calla lily cultivars(Zantedeschia spp, cv. Sunlight, cv. Chiante, cv. Pink Persuation) were cultured on Murashige and Skoog medium supplemented with different plant growth regulators. The formation rate of callus, organogenesis and in viかo tuber production among the three cultivars were tested. Callus was obtained from cvs. Sunlight, Chiante and Pink Persuasion; the best cultivar was Sunlight. Sunlight induced $53.3\%$ callus and Chiante had the highest rate of $56.7\%$ direct shoot regeneration on medium with 2.0 mg/L BA. Regeneration frequencies ranged from 20 to $70\%$ on medium with 2.0-3.0 mg/L BA. The highest percentage of regeneration and the greatest number of shoots were obtained on medium containing 3.0 mg/L BA in three cultivars. Cytokinins induced multiple shoot formation; 1.0 mg/L of 2ip, 5.0 mg/L of BA, and 1.0 m/L of BA induced 16, 14 and 12 multiple shoots in cvs. Sunlight, Chiante and Pink Persuasion, respectivly. 1.0 mg/L of IAA enhanced root growth in cvs. Sunlight and Chiante while cv. Pink Persuasion exhibited enhanced root growth at 2.0 mg/L of IBA. NAA, however, induced no change in root growth. The addition of 90 g/L sucrose enhanced in vitro tuber formation and following tuber expansion in cv. Sunlight, while 70 g/L of sucrose was effective in cvs. Chiante and Pink Persuasion.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.311-322
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• 2003

Mycorrhizae is well known to increase the uptake of P and other mineral nutrients of plants. But if available P levels in soil is too low or high, mycorrhizae formation is limited. This study was carried out to determine the optimum level of available P for mycorrhizae formation of Poncirus trifoliata (trifoliate orange) seedling in volcanic ash soil. Eight levels of P in the range $0-1050mg\;kg^{-1}$ were applied with double superphosphate, and in each P level mycorrhizal fungi inoculated and uninnoculated treatments were included. The seedlings were grown in a greenhouse for 5 months and mycorrhizae formation, growth, and nutrient uptake were measured. As P application level increased, mycorrhizae formation increased at lower range of P application and the highest formation ratio of 43% was found at $100mg\;kg^{-1}$ P level ($2.6mg\;kg^{-1}$ available P in soil). At further higher levels of P application, mycorrhizae formation was rather suppressed. Seedling growth was increased by the inoculation of mycorrhizal fungi, and maximum growth was found at $100mg\;kg^{-1}$ P level where mycorrhizae formation was highest. The growth and mineral nutrient uptake of Poncirus trifoliata seedling represented a significant positive correlation with mycorrhizae formation at all P treatments.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.193-198
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• 2002

The objective of this study was to determine the effects of phenylacetic acid (PAA) on embryo production in anther and microspore culture of herbaceous peony (Paeonia lactiflora Pall.). The anthers of herbaceous peony were cultured on MS medium with 0 to 100 mg/L PAA according to two-step culture method. The ruptured anthers were transferred onto embryo formation medium without growth regulators. The MS medium with 2 mg/L PAA was effective in enhancing of direct embryogenesis and producing of normal embryo with two cotyledons from the cultured anthers. However, the increase of PAA concentration more than 5 mg/L PAA inhibited the embryo formation and promoted to callus formation from the anthers. The PAA affects significantly on the division of microspore and embryo formation in shed pollen culture and the best result was obtained from a medium supplement with 2 mg/L PAA. The preculture of anther for 10 days on solid medium with 2 mg/L PAA was effective for embryo formation from shed microspore of herbaceous peony.

• Journal of Korea Game Society
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• v.6 no.3
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• pp.43-50
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• 2006

This study is to develop a learning program supporting how to teach multi-level of students in number and operating field in the elementary school. Mathematics requires different teaching ways for various standards of student in the school. However, in most of elementary school teachers are having hard time giving the proper lesson for each student due to the lack of supplementary classes and the excessive numbers of students in a class. Thus this research provides "Game-type learning Program" and supports individual learning lessons to give each student an opportunity to form a correct concept of number and operation. This system sets up suitable steps for each student by checking their leaning progress and accomplishment. When a student has a trouble, can give a help or show specific things which could be related with the matter. As a result, students have got more interests in studying math, furthermore, actually, the help and giving a clue helped students a lot in settling the problems.

• Science of Emotion and Sensibility
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• v.16 no.4
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• pp.481-492
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• 2013

This study sorted scores of individual characteristics and multiple intelligence by sex, handle, blood type and age through previous questionnaire with 462 adult males and females. Then electrode was attached to prefrontal lobes Fp1 and Fp2 with EEG measuring system and changes of concentration between no stimulation state and pure pink noise stimulation and their relations to multiple intelligence were examined. As a result of analysis of covariance, the mean concentration of all subjects was significantly higher in the pink noise stimulation compared to no stimulation. According to individual characteristics, concentration was significantly higher in left-hander, type A blood, and group in their thirties except for gender. Concentration in pink noise state strengthened the relation to spatial intelligence and made negative correlations with musical intelligence compared to no stimulation state. These results suggested that individual characteristics should be reflected on using pink noise for improving concentration.

• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.19-22
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• 1975

Freezing resistance of ten cultivars of Chestnut (Castanea crenata S. et Z.) collected from four different sites of Kyunggi Province, Korea on March 2, 1975, was measured to find out the differences among tissue parts, and those among cultivars. The freezing and thawing rates were controlled lower than $6^{\circ}C/hr$. which occurs in nature. The resistance to low temperature was in order from lowest to highest; winter bud, cambium, xylum ray parenchyma and bark cortex. The difference in cold hardiness among cultivars was not consistent among tissue parts of twig stem except in cultivar Dan-Taeck of which all tissue parts showed highest cold-hardiness. The importance of the study on the seasonal variation in cold hardiness of different tissue parts was discussed in terms of choosing the most cold resistant Chestnut culitivar in Korea.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.717-720
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• 2008

In this study, the geographical origin of beef was studied using an electronic nose based on mass spectrometer. Domestic beef was compared with the imported beef from New Zealand and Australia. Each sample was analyzed, and discriminant function analysis was used utilized for the discrimination of geographical origin. The $R^2$ and F-value of discriminant function analysis (DFA)1 were 0.4317 and 14.18, respectively when the samples were separated by geographical origin. The $R^2$ and F-value of DFA1 were 0.8960 and 22.98, respectively when the samples were separated by part of beef.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.5
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• pp.293-303
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• 2004

This experiment was conducted to investigate the direction or orientation of clay particle movement in argillic horizons (Bt) for clarifying the soil classification of soils. Soil samples were collected from 22 soil series containing Bt horizons. Physical and chemical characteristics and mineral and chemical compositions of clay in the soils were analyzed. Micoromorphological characteristics of the Bt horizons were also investigated with thin sections of the natural undisturbed and oriented soil samples. Average clay content in the Bt horizons was 28% and 1.33 times higher comparing to that in the surface layer. Soil pH was higher, but cation exchange capacity (CEC) and organic matter content were lower in Bt horizon than those in the surface layer. There was an evidence of clay accumulation in Bt horizons of all soil series examined except Bangog series. Although there was an increase of clay content in the horizons in Bangog series, the clay was not originated from illuviation process. The translocation of clay was in the order of an 2:1 expandable clay minerals > 2:1 non-expandable clay minerals > 1:1 clay minerals. The illuvial substances in argillic horizon were composed with clay, amorphous iron and opaque mineral. The micoromorphological features of Bt horizon were void coating, channel infilling and grain coating. There was an apparent boundary between clay coating and the groundmass in residuum and colluvium, but Bt horizon of alluvium was composed of a skew plane amputated by the physical operation.

• Journal of the Korean Geographical Society
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• v.47 no.3
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• pp.375-389
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• 2012

Many policy makers believe that geographically clustered business activities, in order to stimulate regional innovation, are the keys to development. Underlying the assumption between cluster and development, mere co-located forms engaged in innovative process helped from knowledge transmission locally. To address the constraints of creative economy, creative milieu require networking to support innovation activities. This paper examines the development of the mini cluster reconsidered in creative milieu that shifted environment development through network activities. It shows that the powerful node get more powerful, weak node get weaker in institutional network. Moreover, the significant of cluster in creative milieu is that brings out synergy to spill over knowledge through inter-relationship based on face-to-face meeting. Creative milieu benefits from and contributes to the competitiveness of the city, they are also embedded in its network activities.