• Journal of Korean society of Dental Hygiene
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• v.7 no.1
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• pp.53-59
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• 2007

Yam was stepwise extracted with hexane, chloroform, ethyl acetate, butanol, and water. Antibacterial activity of each extract was investigated. 1. Methanol extract of Yam was examed against to antibacterial effects on S. mutans KCTC 5316, P. gingivalis KCTC 5352, S. aureus KCTC 1927 by means of agar diffusion method. 2. The methanol extract of Yam was showed very powerfull antibacterial activity on S. mutans, but not showed on P. gingivalis, and S. aureus. 3. The MIC of Yam hexane fraction was 0.25 mg/ml for S. mutans KCTC 5316. 4. The Yam hexane fraction strong inhibited the growth of S. mutans, in the culture medium at concentration of 0.25 mg/ml.

• Journal of Digital Convergence
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• v.9 no.1
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• pp.1-12
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• 2011

The power of the internet community as a social network exerts great influence on all areas of our society not only on knowledge creation and knowledge sharing but also on politics, economy, and culture. This study aims to investigate how the diffusion process of information evolves on the internet in the new environment. The focus of the study is particularly on aspects of using information and the process of information production and the types and methods of online communities. It is the goal of the study to clarify aspects of the online community as an important mediator among universal means of communication in our society. Ways of social communication are changing rapidly and thus the reasoning for this change is very important policy issues to form a social consensus.

• Journal of the Korean Operations Research and Management Science Society
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• v.40 no.2
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• pp.79-93
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• 2015

Today, consumer needs are diversified, continually changing and differentiated. Under the market conditions of unlimited competition to satisfy those needs, businesses focus on relationship-building with customers, as well as on quality of service. As interests in the coffee market rise, in these days, coffee culture diffusion and coffee franchise chain increase have been proceeding under the lead of the young people. This study aims to find the effects of service quality on customer (Korean, Chinese and Foreigner) satisfaction using logistic regression. The results of this study show somewhat different characteristics depending on the characteristics of country people. It is expected that this study can be very useful in regard to similar business.

• Journal of the Korean association of regional geographers
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• v.1 no.1
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• pp.103-116
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• 1995

The purpose of this paper is to explore a brief review of trends in existing geographical research on music and to analyze music by the 5 themes of geography and to explore a variety of classroom techniques which examine song lyrics for their geographic content. The results of this paper are summarized as followed : Firstly, the trends in geographical research on music can be classified into five areas, the first is on spatial diffusion in music, the second on spatial diffusion in music, the third on regional division in music, the fourth on regional characteristics in music, the fifth on pedagogical tools in the teaching of geography. Secondly, music holds numerous possibilities for regional geographical study. The lyrics of music are littered with geographical term through which song writers impart image of culture, the distinct geographical nature of music lyrics gives rise to many geographical question, also, music lyrics gives place its special character. The results of analyses by the 5 themes of geography indicate that music are useful to learning of regional geography. The application of music to learning regional geography attracts much attentions. In the respect of importance of learning new regional geography, and in the respect of adapting globalization have to be focused on this subject.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.380-388
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• 2012

A total of 5 different polar microorganisms were isolated from Arctic lichens and their bioactive compounds were extracted from cell culture using different solvents including acetone, water, chloroform, diethylether, ethanol, ethyl acetate, methanol, and petroleum ether. The antibacterial properties of the extracts were evaluated by disk diffusion tests and minimal inhibitory concentration tests against 6 bacterial pathogens; Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Enterobacter cloacae, Pseudomonas aeruginosa and Escherichia coli. Among the extraction samples, ethyl acetate extracts of Burkholderia sordidicola S5-$B^T$ (KOPRI 26644) showed the highest activity (inhibition zone, 7-10 mm; MIC value, 57.5-1000 ug/ml) against targeted bacteria. Among the various solvents used for extraction, chloroform extract exhibited the weakest, but still obvious, activity.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.444-447
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• 2015

This study was carried out to determine the antibacterial activity of $SeO_2$ against pathogenic bacteria, methicillin-resistant Staphylococcus aureus (MRSA). Using the disc diffusion method, $SeO_2$ showed higher antibacterial activity against Gram-positive bacteria than Gram-negative bacteria used in this study. Coccus-form bacteria showed much susceptible to $SeO_2$, compared to bacillus-form bacteria. Compared to antibiotics-susceptible S. aureus, antibiotics used in this study showed lower antibacterial activity against MRSA. As $200-500{\mu}g/disc$ of $SeO_2$ was applied, diameters of clear zone for S. aureus and MRSA were 20-32.7 mm and 13.5-17.9 mm, respectively. For MRSA, minimal inhibitory concentration of $SeO_2$ was $40{\mu}g/ml$. When $SeO_2$ was added in culture broth, cell growth of MRSA was inhibited. These results will be applied to determine antibacterial mechanism of MRSA and other pathogenic microorganisms.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.38-44
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• 2006

A simple and easy modification of AST by disk diffusion was tested for the detection of induced clindamycin resistant Staphylococci and their antimicrobial susceptibility at the same time. The incidence of inducible clindamycin resistant staphylococci in blood culture and their MIC characterization at Seoul National University Hospital was analyzed by an AST contained disk approximation test (D-zone test) and Etest, respectively. Of the total 309 staphylococcal isolates, 139 (45%) isolates presented constitutive resistance to ERY and CLI (ERY-R, CLI-R phenotype), and 59 were ERY-I/R and CLI-S phenotypes. Of the 59 isolates, 19 (32%) isolates were inducible resistant to CLI. The incidence was higher in S. aureus (66.7%) than coagulase-negative staphylococci (CNS, 26.0%). Especially, methicillin-resistant staphylococci (MRSA, 100%; MRCNS, 45.5%) presented higher inducibility than methicillin susceptible (MSSA, 50%; MSCNS, 20%). For most of the inducible clindamycin resistant staphylococci (15 of 19 isolates), their ERY MIC were high (>$128_{\mu}g/mL$) and were methicillin resistant. The remaining 4 isolates were methicillin susceptible and their ERY MIC were of intermediate concentrations ($1-4_{\mu}g/mL$). We concluded that suscetibility testing of staphylococci, especially methicillin resistant, should include the D-zone test.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.244-253
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• 2018

This study was carried out to evaluate effects of antimicrobial substances produced by isolated soil bacteria. Among two thousands of bacterial isolates Paenibacillus elgii DS381 exhibited high antimicrobial activities against several microbial residents on human skin and pathogenic bacteria. DS381 showed 15.3~26.0 mm inhibition zone diameter against all target bacteria and yeast in agar well diffusion test. Antimicrobial peptide produced by DS381 indicated low minimum inhibitory concentration (0.039-5.000 mg/ml). DS381 produced biosurfactant such as lipopeptide, and surface tension of culture supernatant of DS381 reduced from 60.0 to 40.3 mN/m. DS381 also showed $1.56{\pm}0.13U/ml$ of chitinase activity. These results suggest that Paenibacillus elgii DS381 may be utilized as an efficient biocontrol agent against some important human skin microbes and pathogenic bacteria.

• Restorative Dentistry and Endodontics
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• v.29 no.6
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• pp.498-503
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• 2004

The properties of ideal root canal sealers include the ability of sealing the total root canal system and no toxic effects to periradicular tissues. Cytotoxicity test using cell culture is a common screening method for evaluation of the biocompatibility of root canal sealers. The purpose of this study was to investigate the cytotoxic effect of newly developed resin-based sealer (Adseal 1, 2, and 3) comparing with those commercial resin-based sealers (AH26 and AH Plus), ZOE-based sealers (Tubliseal EWT, Pulp Canal Sealer EWT) and calcium hydroxide based sealer (Sealapex), An indirect contact test of cytotoxicity by agar diffusion was performed according to the international standard ISO 10993-5. L929 fibroblast cells were incubated at $37^{\circ}C$ in humidified 5% $CO_2-containing$ air atmosphere. The freshly mixed test materials were inserted into glass rings of internal diameter 5 mm and height 5 mm placed on the agar. After the 24 hrs incubation period, the decolorization zones around the test materials were assessed using an inverted microscope with a calibrated screen. A Decolorization Index was determined for each specimen. Adseal 1. 2, and 3 did not exert any cytotoxic effects, whereas AH26, AH Plus, Tubliseal EWT, Pulp Canal Sealer EWT, and Sealapex produced mild cytotoxicity.

• Journal of Sasang Constitutional Medicine
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• v.26 no.2
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• pp.133-145
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• 2014

Objectives In this study, we tried to examine that Sasang Constitutional differences affect the direction of the treatment of anger by comparing the effect of mindfulness meditation for anger scale in accordance with the difference of the constitution. Methods We analysed 105 college student's Constitution by Questionnaire for the Sasang Constitution Classification II and the effect of mindfulness meditation for anger by State-Trait Anger Expression Inventory Korean version(STAXI-K), Korean Version of the Behavioral Anger Response Questionnaire(K-BARQ). Volunteers who participated in this study were 105 people, except for person that did not properly entered the anger scale and Questionnaire for the Sasang Constitution Classification II, the subjects of analysis for State-Trait Anger Expression Inventory Scale were 45 and for the Behavioral Anger Scale were 49. Results & Conclusions The result of the effects of mindfulness meditation according to Sasang Constitution was as follows. The tendency to try to disperse and avoid the anger was increased through meditation for all subjects. The diffusion of male subjects and the avoidance of female subjects was increased. The effect of meditation on anger did not differ according to Sasang Constitution, constitutional differences did not affect the effects of meditation. The tendency of avoidance of anger was increased in Soyangin, Anger-out was decreased and the tendency of avoidance and diffusion of anger were decreased in Taeeumin through meditation.