• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.283-291
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• 2012

Bioremediation efforts often rely on the application of surfactants to enhance hydrocarbon bioavailability. However, synthetic surfactants can sometimes be toxic to degrading microorganisms, thus reducing the clearance rate of the pollutant. Therefore, surfactant-resistant bacteria can be an important tool for bioremediation efforts of hydrophobic pollutants, circumventing the toxicity of synthetic surfactants that often delay microbial bioremediation of these contaminants. In this study, we screened a natural surfactant-rich compartment, the estuarine surface microlayer (SML), for cultivable surfactant-resistant bacteria using selective cultures of sodium dodecyl sulfate (SDS) and cetyl trimethylammonium bromide (CTAB). Resistance to surfactants was evaluated by colony counts in solid media amended with critical micelle concentrations (CMC) of either surfactants, in comparison with non-amended controls. Selective cultures for surfactant-resistant bacteria were prepared in mineral medium also containing CMC concentrations of either CTAB or SDS. The surfactantresistant isolates obtained were tested by PCR for the Pseudomonas genus marker gacA gene and for the naphthalene-dioxygenase-encoding gene ndo. Isolates were also screened for biosurfactant production by the atomized oil assay. A high proportion of culturable bacterioneuston was tolerant to CMC concentrations of SDS or CTAB. The gacA-targeted PCR revealed that 64% of the isolates were Pseudomonads. Biosurfactant production in solid medium was detected in 9.4% of tested isolates, all affiliated with genus Pseudomonas. This study shows that the SML is a potential source of surfactant-resistant and biosurfactant-producing bacteria in which Pseudomonads emerge as a relevant group.

• The Journal of Korean Association of Computer Education
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• v.12 no.3
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• pp.11-22
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• 2009

Scratch, one of the educational programming languages, provides a media-rich programming environment and easy interface to users. It supports Korean language and is utilized usefully in programming classes in elementary and middle schools. However, programming causes cognitive loads to young students. Because the programming process is a complex problem solving procedure that requires logical and abstract thinking abilities. Therefore, we developed a problem based scratch programming teaching and learning model to enhance intrinsic motivation of learners and to maximize the effects of using the scratch, educational programming language. The developed problem based teaching and learning model considered elementary students' characteristics. It was implemented in fifth grade elementary school classes and the educational effects of the model was analysed. The developed model was helpful in enhancing students' problem solving potential and logical thinking abilities.

• Journal of Digital Convergence
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• v.15 no.12
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• pp.549-554
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• 2017

In recent years, as the importance of history has increased through various social issues, media, and journalists in Korea, it has led to the value of 'right history' and 'teaching history that is right. History of a country is also a core asset in a country 's cultural contents industry, and historical relics are important to prove its value. As the interest in the historical and cultural heritage has increased, researches to develop it as cultural contents by restoring it as information and communication technology such as multimedia and virtual reality are active. In this paper, we propose convergence device and contents that can provide rich experience and various learning opportunities in artifact experience through restoration of artifacts using augmented reality. The study on the application effect of educational game contents which can add fun can be continued.

• Korean Journal of Community Nutrition
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• v.4 no.4
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• pp.546-553
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• 1999

This study was undertaken to develop and evaluate a nutrition education program with internet for students. A survey was conducted to find out needs for nutrition education program with 430 college or high school student in October, 1997. Eighty four point eight percent of female and 36.0% of male students had a plan to reduce their weight in a near future. Forty four point four percent of subjects obtained information about weight control from mass media, 28.6% of subjects obtained from their neighbor's recommendation. The information wanted to know were high-calorie foods, answered by 42.1% of females, and calorie expenditure of exercise, answered by 31.9% of males. The obese group showed higher preferrence to sweet foods, salty foods, hot foods, convenience foods, processed foods, animal foods, fried and oily foods, and eating-out than normal group(p<0.05). The obese group also showed a tendency of bad food habits, low intake of seaweeds, high intakes of animal fat, cholesterol-rich foods and salty foods. Amount of food intakes was inappropriate in obese group. An internet program for nutrition education was developed using the results of the survey and juvenile nutrition programs. The program consisted of 6 steps ; step 1 was to check one's physical status, step 2 was explanation about good food habits, step 3 was about food management, step 4 was methods of exercise for health, step 5 included how to maintain ideal weight, and step 6 was related-internet site. Pre-education test and post-education test was conducted to evaluate the nutrition education through internet. The score of nutrition knowledge increased from $74.2{\pm}7.4$ to $77.2{\pm}9.6.$ The score of food attitude did not change. The subjects wanted more information about nutrition from internet. Therefore, internet program of nutrition education with specific and interesting topics should be developed more.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.3
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• pp.273-301
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• 2008

This study aims not only to examine the globalization, imformationization, and networking as background of knowledge-information-based society, but also to clarify the research fields of 'geography of knowledge' and further research themes for economic geography in a knowledge-information-based society. As a result of globalization, the degree of regional disparity, which had decreased with neoliberal policy in Europe and America in 1980's, has increased in early development states such as China and Eastern European countries. In opposition to the globalization that has led to increasing regional disparities at a global scale, many scholars argue that grassroots globalization or globalization from below is needed. Based on a pessimistic view on globalization, many maintain that unequal access to information has enlarged the gap between rich and poor. They also argue that the study of the geography of poverty is crucial in oder to solve the problem of bipolization. According to the world system theory, spatial grasp of commodity chains, actors' diversities, flows towards innovation in learning knowledges, and geographical, organizational, and institutional proximities are intertwined. Because these elements make significant influences each other in social networks, the interrelationships among those elements should be carefully considered. A 'geography of knowledge' deals with manufacturing, finance and service, media, cultural, and creative industries. Former researches in economic geography have tended to deal with those industries separately without attempting to make meaningful linkages among discussions on those industries.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.15-21
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• 2013

We previously observed that Bacillus subtilis spores from sspE mutants presented a lower germination capacity in media containing high salt concentrations (0.9M NaCl). This deficiency was attributed to the absence of SASP-E (gamma-type small-acid-soluble protein), rich in osmocompatible amino acids released by degradation. Herein we observed that, in addition, this mutant spore presented a reduced capacity to use L-alanine as germinant (L-ala pathway), required longer times to germinate in calcium dipicolinate ($Ca^{2+}$-DPA), but germinated well in asparagine, glucose, fructose, and potassium chloride (AGFK pathway). Moreover, mild sonic treatment of mutant spores partially recovered their germination capacity in L-ala. Spore qualities were also altered, since sporulating colonies from the sspE mutant showed a pale brownish color, a higher adherence to agar plates, and lower autofluorescence, properties related to their spore coat content. Furthermore, biochemical analysis showed a reduced partition in hexadecane and a higher content of $Ca^{2+}$-DPA when compared with its isogenic wild-type control. Coat protein preparations showed a different electrophoretic pattern, in particular when detected with antibodies against CotG and CotE. The complementation with a wild-type sspE gene in a plasmid allowed for recovering the wild-type coat phenotype. This is the first report of a direct involvement of SASP-E in the spore coat assembly during the differentiation program of sporulation.

• Journal of KIISE
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• v.42 no.1
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• pp.122-129
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• 2015

This paper proposes a method for providing the information about multimedia streams for telepresence services to heterogeneous services such as IMS (IP Multimedia Subsystem) and RTCWeb (Real-Time Communication in WEB-browsers). First of all, we design an interworking gateway for each service and suggest a procedure for providing the information about multimedia streams, which is defined by CLUE, a working group for standardization, to the heterogeneous services. We also apply the method of the actual CLUE information exchange and implement it in our experiment environment. Finally, we show that the proposed method can exchange more information than previous methods even though the media session re-establishment time is similar to legacy systems in terms of performance analysis. With the proposed method, the heterogeneous services can collect a variety of information about the telepresence service and use it according to user preference. In this way it provides rich multimedia streaming services for many areas.

• Journal of Life Science
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• v.12 no.3
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• pp.325-331
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• 2002

There is growing interest ill understanding the role and mechanisms of flavonoid as antioxidant on LDL. The antioxidative activity of flavonoid typically present in Oenothers odorate Jacquin was investigated in vitro using a human LDL oxidation assay. In present work, LDL was incubated with increasing concentrations of extracts of extracts of Oenothers odorate Jacquin and LDL oxidation was started by adding CuSO$_4$to the media. Substances in leaves extracts of Oenothers odorate Jacquin are capable of inhibiting the initiation and the propagation of LDL oxidation. They inhibit LDL oxidation, monitored by thiobarbituric acid-reactive substances(TBARS), as well as modification as shown through direct measurement of electrophoretic mobility, diene conjugates. Inhibition is a dose dependent effect that becomes already apparent at concentration of extracts as low as 40$\mu\textrm{g}$/mL. Inhibition is almost complete at 80$\mu\textrm{g}$/mL. Extracts of Oenothers odorate Jacquin were more potent antioxidative activity than either ascorbic acid and dl-a -tocopherol.

• Journal of Broadcast Engineering
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• v.26 no.5
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• pp.643-651
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• 2021

Most people acquire information visually. Screens of computers, smart phones, etc. constantly stimulate people's eyes, increasing fatigue. In this social phenomenon, the realistic and rich sound of the 21st century's state-of-art sound system can affect people's bodies and minds in various ways. Through sound, human beings are given space to calm and observe themselves. The purpose of this paper is to introduce immersive yoga training based on 3D sound conducted together by ALgruppe & Rory's PranaLab and to promote the understanding of immersive audio system. As a result, people, experienced immersive yoga, not only enjoy the effect of sound, but also receive a powerful energy that gives them a sense of inner self-awareness. This is a response to multidisciplinary exchange required by the knowledge of modern society, and at the same time, informs the possibility of new cultural contents.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.8-8
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• 2019

The stringent response (SR) is characterized as a bacterial defense mechanism in response to various growth-inhibiting stresses. It is activated by accumulation of a small nucleotide regulator, (p)ppGpp, and induces global changes in bacterial transcription and translation. Recent work from our group has shown that (p)ppGpp plays a critical role in virulence and survival in Vibrio cholerae. The genes, relA and relV, are involved in the production of (p)ppGpp, while the spoT gene encodes an enzyme that hydrolyzes it in V. cholerae. A mutant strain defective in (p)ppGpp production (i.e. ${\Delta}relA{\Delta}relV{\Delta}spoT$ mutant) lost the ability to produce cholera toxin (CT) and lost their viability due to uncontrolled production of organic acids, when grown with extra glucose. In contrast, the ${\Delta}relA{\Delta}spoT$ mutant, a (p)ppGpp overproducer strain, produced enhanced level of CT and exhibited better growth in glucose supplemented media via glucose metabolic switch from organic fermentation to acetoin, a neutral fermentation end product, fermentation. These findings indicates that (p)ppGpp, in addition to its well-known role as a SR mediator, positively regulates CT production and maintenance of growth fitness in V. cholerae. This implicates SR as a promising drug target, inhibition of which may possibly downregulate V. cholerae virulence and survival fitness. Therefore, we screened a chemical library and identified a compound that induces medium acidification (termed iMAC) and thereby loss of wild type V. cholerae viability under glucose-rich conditions. Further, we present a potential mechanism by which the compound inhibits (p)ppGpp accumulation. Together, these results indicate that iMAC treatment causes V. cholerae cells to produce significantly less (p)ppGpp, an important regulator of the bacterial virulence and survival response, and further suggesting that it has a therapeutic potential to be developed as a novel antibacterial agent against cholera.