• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.619-628
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• 2014

To identify lipase LipA (PFL_0617) from Pseudomonas protegens Pf-5, a lipA deletion mutant (Pf0617) and a complementary strain (Pf0617lipA) were constructed, and their effects on the lipase production were examined. Pf0617 remarkably decreased its whole-cell lipase activity, whereas Pf0617lipA made its whole-cell lipase activity not only restore to wild-type level but also get a further increment. However, the deletion and overexpression of lipA did not affect the extracellular lipase activity. In addition, the unbroken whole cells of these strains were able to catalyze the hydrolysis of membrane-permeable p-nitrophenyl esters, but could not hydrolyze the membrane-impermeable olive oil. These results confirmed that LipA was an intracellular lipase and Pf-5 could also be used as a natural whole-cell biocatalyst. To evaluate the potential of Pf-5 as a whole-cell biocatalyst and separately characterize the whole-cell LipA, the properties of the whole-cell lipases from Pf-5 and Top10lipA were characterized. The results demonstrated that both Pf-5 and Top10lipA exhibited high tolerance to alkaline condition, high temperature, heavy metal ions, surfactants, and organic solvents. Taken together, lipA can realize functional expression in E. coli Top10, and Pf-5 and Top10lipA as whole-cell biocatalysts may have enormous potential in applications.

• Nutrition Research and Practice
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• v.4 no.1
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• pp.51-57
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• 2010

We performed this study to examine lifestyle patterns and dietary behavior based on the level of Internet addiction of Korean adolescents. Data were collected from 853 Korean junior high school students. The level of Internet addiction was determined based on the Korean Internet addiction self-scale short form for youth, and students were classified as high-risk Internet users, potential-risk Internet users, and no risk Internet users. The associations between the students' levels of Internet addiction and lifestyle patterns and dietary behavior were analyzed using a chi-square test. Irregular bedtimes and the use of alcohol and tobacco were higher in high-risk Internet users than no risk Internet users. Moreover, in high-risk Internet users, irregular dietary behavior due to the loss of appetite, a high frequency of skipping meals, and snacking might cause imbalances in nutritional intake. Diet quality in high-risk Internet users was also worse than in potential-risk Internet users and no risk Internet users. We demonstrated in this study that high-risk Internet users have inappropriate dietary behavior and poor diet quality, which could result in stunted growth and development. Therefore, nutrition education targeting high-risk Internet users should be conducted to ensure proper growth and development.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.233-241
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• 2013

The purpose of this study was to evaluate the effectiveness of the education program developed to raise the potential of entrepreneurial capabilities of senior citizens under the supervision of SMBA and investigate the effects of educational contents and environment on program satisfaction and entrepreneurial intention. The sample of this study was composed of 44 trainees who participated in the education program implemented by H University. Data were collected using self-administered questionnaires and analyzed employing paired-sample t-test and path analysis techniques. The study found that the program was effective in strengthening the potential of entrepreneurial capabilities of senior citizens and that educational content and environment had positive effects on program satisfaction, which in turn, positively impacted on entrepreneurial intention. The practical implications of the findings were discussed and the future directions for research were suggested.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.627-640
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• 2008

The geometrical structures, atomic charges, and relative energies of tetracoordinated Pd complexes [PdCl3Z (Z = Cl-, Br-, OH?-, H2O, NH3, PH3), PdCl2Z2 (Z = Br-, OH?-, H2O, NH3, PH3), PdZ?2X (Z = Cl-, OH?-, H2O, NH3, PH3; X = oxalate, O2-?CCO2-), and PdZ2Y (Z = Cl?-, OH?-, H2O, NH3, PH3; Y = succinate, CO2-?CHCHCO2-?)] and the ligand exchange reactions of the Pd complexes were investigated using the ab initio second order Mller-Plesset perturbation (MP2) and Density Functional Theory (DFT) methods. The geometrical characteristics of the tetracoordinated Pd(II) complexes with mono- and bidentate ligands, the effects of the atomic charges for the charged and uncharged ligands, the (dz2-p ) interactions between the dz2-orbital of Pd(II) and the p -orbital of bidentates, and the relative stabilities between the isomers of PdCl2Z2 and PdZ2Y were investigated in detail. The potential energy surfaces for the ligand exchange reactions used for the conversions of {[PdCl2(NH3)2] + H2O} to {[PdCl(NH3)2(H2O)]+ + Cl?-?} and {[PdCl2(PH3)2] + H2O} to {[PdCl(PH3)2(H2O)]+ + Cl?-?]} were investigated. The geometrical structure variations, molecular orbital variations (HOMO and LUMO), and relative stabilities for the ligand exchange processes were also examined quantitatively.

• BMB Reports
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• v.51 no.4
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• pp.200-205
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• 2018

Exercise and resveratrol supplementation exhibit anti-obesity functions in the long term but have not been fully investigated yet in terms of their early potential effectiveness. Mice fed with high-fat diet were categorized into control (Cont), exercise (Ex), resveratrol supplementation (Res), and exercise combined with resveratrol supplementation (Ex + Res) groups. In the four-week period of weight loss, exercise combined with resveratrol supplementation exerted no additional effects on body weight loss but significantly improved whole-body glucose and lipid homeostasis. The combined treatment significantly decreased intrahepatic lipid content but did not affect intramyocellular lipid content. Moreover, the treatment significantly increased the contents of mtDNA and cytochrome c, the expression levels of peroxisome proliferator-activated receptor gamma coactivator-1 alpha and its downstream transcription factors, and the activities of ATPase and citrate synthase. However, exercise, resveratrol, and their combination did not promote myofiber specification toward slow-twitch type. The effects of exercise combined with resveratrol supplementation on weight loss could be partly due to enhanced mitochondrial biogenesis and not to fiber-type shift in skeletal muscle tissues.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.582-588
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• 2009

Direct electron transfer of hemoglobin (Hb) in the chitosan (CTS) and $TiO_2$ nanoparticles (nano-$TiO_2$) composite films was achieved by using a room temperature ionic liquid of 1-butyl-3-methylimidazolium hexafluorophosphate ($BMIMPF_6$) modified carbon paste electrode (CILE) as the basal electrode. UV-Vis and FT-IR spectroscopy indicated that Hb in the film retained the native structure. Electrochemical investigation indicated that a pair of well-defined quasi-reversible redox peaks of Hb heme Fe(III)/Fe(II) was obtained with the formal potential located at -0.340 V (νs. SCE) in pH 7.0 phosphate buffer solution (PBS). The electrochemical parameters such as the electron transfer coefficient (α), the electron transfer number (n) and the standard electron transfer rate constant ($k_s$) were got as 0.422, 0.93 and 0.117 $s^{-1}$, respectively. The fabricated CTS/nano-$TiO_2$/Hb/CILE showed good electrocatalytic ability to the reduction of trichloroacetic acid (TCA) and hydrogen peroxide ($H_2O_2$), which exhibited a potential application in fabricating a new kind of third generation biosensor.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.540-547
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• 2022

Online education is a major trend in the future education change and the COVID-19 pandemic has further accelerated the process. Online education has become an important part of the modern education system because of its stability and continuity. However, the disadvantages of traditional online education can reduce users' experience, thus upgrading online education is the key to future education. Metaverse, as a new platform for online education, redefines the occurrence space of online education, changes the teaching mode and learning and evaluation methods of online education, and shows its development potential. This research analyzed the characteristics of Metaverse and its technological development status, and then proposed an intelligent online education environment construction scheme based focused on Metaverse of art education.

• Journal of the International Relations & Interdisciplinary Education
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• v.1 no.1
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• pp.13-23
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• 2021

This article identifies the nature of international relations and education and examines their potential. To achieve this goal, international relations and education can be found in supporting economically deprived regions and contributing to the development of the world based on mutual understanding. Next, the current status of international education exchanges was examined by the Ministry of Education, the National Institute for International Education, and the Gyeongnam Office of Education's International relations and Education Center. The status of international relations and education shown in these three subjects is active in practice, but there was also a limit to theorizing about them and making explanations or predictions. Based on this, the possibility of international education exchanges was discussed by the government or education office, which can bring about educational autonomy, contribute to the growth of the country through support for resource-poor countries, limited development assistance, poor academic development.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.974-990
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• 2012

The purpose of this study was to explore practical meanings of convergence education and to seek ways of implementing it in school science education. The study adopted focus group interview method in order to elicit science teachers' perceptions and practical knowledge related to various ways of integrating educational aims and contents from the perspectives of science education. Two focus group interviews were held with four science teachers with the themes of the concept and potential of convergence education, and the implementation and systemic support, respectively. The qualitative data was analyzed by deriving major themes comprising teachers' perception on convergence education: they are 1) related concepts and rationales, 2) contents, methods, and assessment, 3) the characteristics of the science subject that make it suitable for convergent education, 4) teacher perception and professionalism required for implementing convergent education, and finally 5) environmental conditions for putting the idea into practice. Based on this result, the study discusses conceptual and practical issues for implementing convergence education in ways that contribute to overcoming the problems of the traditional educational system and reorienting science education towards the future society.

• Korean Journal of Mathematics
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• v.26 no.2
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• pp.327-335
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• 2018

In this paper, we present the construction of natural invariant measures so called SRB(Sinai-Ruelle-Bowen) measures by the properties of geometric t-potential and Bowen's equation for the hyperbolic attractors.