• Journal of Food and Nutrition Research
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• v.9 no.3
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• pp.163-169
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• 2021

Decreased adipocyte fatty acid oxidation (FAO) and impaired preadipocyte differentiation characterize hypertrophic expansion of adipose tissue (AT) from obese and insulin resistant humans and are recognized as potential mechanisms for obesity-mediated dyslipidemia. Supplementation of formononetin (FMN), one of the principal isoflavones extracted from red clover or Huangqi (Astragalus roots), has been shown to have beneficial effects on obesity-related hyperlipidemia, a well-established cardiovascular risk factor. However, a target tissue and underlying mechanism(s) through which FMN acts have been under-investigated. Thus, we investigated whether FMN promotes adipocyte FAO and preadipocyte differentiation using 3T3-L1 preadipocytes to provide potential mechanisms of FMN action. We further extended this to the culture of 10T1/2 mesenchymal stem cells (MSCs) as well as mouse AT explants to reflect in vivo effects of FMN. In fully differentiated 3T3-L1 adipocytes, FMN-treatment significantly increased the expression levels of FAO-related proteins such as pAMPK, pACC, and CPT1, all of which were consistently upregulated in AT explant cultures treated with 10 μM FMN. In addition, FMN significantly enhanced the degree of differentiation of both 3T3-L1 preadipocytes and 10T1/2 MSCs into adipocytes as evidenced by Oil Red O staining of cellular lipids. This observation correlated with increased expression levels of key adipogenic transcription factors (PPARγ and C/EBPα) and their down-stream target proteins (FABP4, Glut4 and adiponectin). Moreover, FMN failed to exert its stimulatory effects on preadipocyte differentiation in both cell types in the presence of a PPARγ antagonist, suggesting a PPARγ-dependent effect of FMN. Collectively, these data provide possible mechanisms of action of FMN on lipid metabolism and further support the favorable in vivo effects of FMN in diet and obesity-induced dyslipidemia.

• Journal of Sensor Science and Technology
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• v.33 no.5
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• pp.274-287
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• 2024

Chemiresistors play a crucial role in numerous research fields, including environmental monitoring, healthcare, and industrial safety, owing to their ability to detect and quantify gases with high sensitivity and specificity. This review provides a comprehensive overview of the recent advancements in photoactivated chemiresistors and emphasizes their potential for the development of highly sensitive, selective, and low-power gas sensors. This study explores a range of structural configurations of sensing materials, from zero-dimensional quantum dots to three-dimensional, porous nanostructures and examines the impact of these designs on the photoactivity, gas interactions, and overall sensor performance-including gas responses and recovery rates. Particular focus is placed on metal-oxide semiconductors and the integration of ultraviolet micro-light emitting diodes, which have gained attention as key components for next-generation sensing technologies owing to their superior photoactivity and energy efficiency. By addressing existing technical challenges, such as limited sensitivity, particularly at room temperature (~22℃), this paper outlines future research directions, highlighting the potential of photoactivated chemiresistors in developing high-performance, ultralow-power gas sensors for the Internet of Things and other advanced applications.

• Journal of the Korean School Mathematics Society
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• v.8 no.1
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• pp.55-75
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• 2005

As part of development research of a gender-neutral mathematics program, this paper provides a discussion of the fearures of the developed mathematics program. Based on the theory of feminist pedagogy and critical theories about women' ways of knowing, this mathematics program for girls pursues the mathematical empowerment of girls. Specifically, this mathematics program facilitates girls' awareness of their mathematical potentials, encourage them to position women at a center of mathematics in order for th equity in mathematics education. For the purpose, this program emphasizes constructive learning through girls' active participation. Thus, the instructions will value girls' own cognitive resources such as their experiential knowledge and ways of mathematical justification and provide an environment to support the growth of girls' own mathematical potential. This developmental research will be furthered to the systematic program evaluation to extend this program to support the equity for the marginalized poppulations as well as girls in mathematics education.

• Journal of the Korean earth science society
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• v.37 no.2
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• pp.79-88
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• 2016

This study aims analyze the geological values in relation to the volcanic area and to investigate a possibility of the geosites and the geoheritages in Byeonsanbando area. The results indicate that the seven geosites are relevant as a potential national geopark, including Gunghang, Solseom Island, and Mohang located in Oebyeonsan and Jikso Falls, Gulbawi, Seongye Falls, and Ulgumbawi located in Naebyeonsan. Solseom Island and Mohang should be preserved and used as a place of the geological study because of their high geological heritage values. Besides, Jeokbyeokgang and Chaeseokgang are famous for excellent natural landscapes as they have been proven with academic values. Like this, these area are considered to have sufficient value as a national geopark of Korea, because their geoheritages are variously distributed in Byeonsanbando area.

• Journal of Korean Dental Science
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• v.12 no.2
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• pp.58-65
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• 2019

Purpose: This study was aimed to investigate the possibility of utilizing smart device-based test (SBT) for competency evaluation in dental education and to analyze the student responses on overall competency evaluation using SBT method, in comparison to ubiquitous-based test (UBT). Materials and Methods: Questionnaire surveys have been conducted at Yonsei University College of Dentistry from 2015 to 2018 to obtain students' feedback on the application of SBT to competency evaluation. In addition, in order to supplement the competency evaluation procedure, considerations were explored by comparing the expected and actual difficulty of each item when preparing items for competency evaluation with SBT. Result: According to the survey results, student responses between the initial two years (2015 and 2016) differed from those in next two years (2017 and 2018). Students in 2017 and 2018 had more positive responses on competency evaluation with SBT. To determine the test validity, criterion-referenced evaluation was adopted to compare the data in 2017 and 2018 and slight differences in test difficulty in 2018 between the expected and actual difficulty of items were found. Conclusion: The results indicated that SBT was more appropriate for competency evaluation than UBT, based on four-year period of competency evaluation. The SBT was not affected by either the file size or the number of test-takers. Interestingly, students were not sensitive to test version of competency evaluation (paper-based test and SBT). This study suggests that the quality of the test items should be measured by continuous monitoring of the expected and actual difficulty of items for determining test validity. More detailed results and discussions of the findings are given for the development of test procedure and further potential research directions in dental education.

• Journal of The Korean Association For Science Education
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• v.22 no.1
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• pp.158-175
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• 2002

In the present study we have compared and analyzed three different measures of creativity in 135 gifted and 161 normal students to understand the nature of creativity and to propose the guideline for measuring creativity. The instruments used to measure creativity in this study are the Torrance Test of Creativity Thinking (TTCT), the Test of Creative Problem solving and Finding in Science (CPFS), and the Creative Behavior Checklist in Science (CBCS). The TTCT is the most widely used divergent thinking test and measures creativity in the aspect of domain-generality. The CPFS and the CBCS were developed for the purpose of this study and measure domain-specific creativity in the area of Science. The findings of this study revealed that gifted students are significantly more creative compared to normal students in all measures of creativity used in the study. The biggest difference between the gifted and normal students was found in the aspect of CPFS. This study implies that creativity, which is considered less useful to identify gifted students compared to achievement or IQ scores, is the important factor to consider for judging giftedness. The low correlations revealed among the TTCT, CPFS, and CBCS imply that the three measures of creativity address relatively different aspects of creativity. The results also suggest that it is essential to consider multiple criteria of creativity not to overlook potential creative students in the area of science. Implications of the study in connection with the identification and educational practices for gifted education program is discussed.

• Journal of Technologic Dentistry
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• v.31 no.1
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• pp.75-97
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• 2009

Objectives: Practice of dental technology poses great potential risk since the manufacturing processes are complex and involve dangerous devices and the students are asked to handle various materials in the casting and processing process. Lacking an understanding of the overall practice process, the beginners of practice are exposed to greater danger due to their unsafe attitudes and poor practice attitudes. This study set out to investigate the students of dental technology for their attitudes toward safety and their practice of safe actions during practice and to provide basic data for safety education to prevent any possible safety incidents during practice. Methodology: The subjects include total 408 dental technology majors in their sophomore and junior year. Based on literature study and previous studies, a structured questionnaire was made, distributed to the subjects right after practice, and gathered on the spot. The questionnaire contained total 60 items, and data were collected from April 20 to May 25, 2006. Results: Collected data were analyzed in frequency and $X(C)^{\sim}$-test using the SPSS 12.0 version. The analysis results show that the students believed that they could prevent safety accidents by following safety rules and guidelines as far as safety attitudes were concerned. However, they did nothing more than paying attention to many practice processes even though they thought they were dangerous. Conclusion: Overall the subjects practiced proper safety actions during practice with significance differences in their behavioral characteristics according to grade, gender and age. The significant differences according to grade seem to derive from safety education before practice, and those according to gender and age have more to do with individual actions and common sense according to gender and age than education. Thus practice teachers need to develop safety education materials for each practice process and provide systematic safety education before practice so that the students can practice safety actions.

• Journal of Home Health Care Nursing
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• v.9 no.1
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• pp.5-13
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• 2002

This study was conducted to assess need for education on the infection control by examining the knowledge on infection control in home care of the home care trainees who had completed an infection control course. Using 64 items questionnaire. home care trainees of eight home care education institutions who took classes related with infection control. The level of knowledge evaluated subjectively was 4.24point (full mark: 5 point). The correct answer rates for handwashing and gloving. cleaning patients' rooms. preventing sharp injury, preventing exposure to potential infectious agents, home care bag technique were 84.5% 86.4% 70.7% 65.3% 76.2% representatively. For the knowledge on the infection control principles to prevent catheter related infection, indwelling catheter related infection, tracheal tube related pneumonia. L-tube related infection, oxygen therapy related infection. and wound infection were 62.8% 27.8% 39.1% 87.8% 76.5% 80.5% representatively. The correct answer rates varied depending upon the educational institutes (p< = .0001), educational levels (p= .001), workplaces (p<.0001), and the experience of infection control education (p= .001). Considering these results. a standardized curriculum must be developed and implemented after analyzing the existing infection control curricula of the home care education institutes. and guide books for infection control in home care should be developed and distributed. In addition. continuous infection control education be provided to the home care nurses through reeducation so they can acquire new knowledge needed for carrying out infection control activities effectively.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.185-195
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• 2015

Glucoamylase is an important industrial enzyme. Glucoamylase production by industrial Aspergillus niger strain featured with two major problems: (i) empirical substrate feeding methods deteriorating the fermentation performance; and (ii) the high raw materials cost limiting the economics of the glucoamylase product with delegated specification. In this study, we first proposed a novel three-stage varied-rate substrate feeding strategy for efficient glucoamylase production in a 5 L bioreactor using the standard feeding medium, by comparing the changing patterns of the important physiological parameters such as DO, OUR, RQ, etc., when using different substrate feeding strategies. With this strategy, the glucoamylase activity and productivity reached higher levels of 11,000 U/ml and 84.6 U/ml/h, respectively. The performance enhancement in this case was beneficial from the following results: DO and OUR could be controlled at the higher levels (30%, 43.83 mmol/l/h), while RQ was maintained at a stable/lower level of 0.60 simultaneously throughout the fed-batch phase. Based on this three-stage varied-rate substrate feeding strategy, we further evaluated the economics of using alternative carbon sources, attempting to reduce the raw materials cost. The results revealed that cornstarch hydrolysate could be considered as the best carbon source to replace the standard and expensive feeding medium. In this case, the production cost of the glucoamylase with delegated specification (5,000 U/ml) could be saved by more than 61% while the product quality be ensured simultaneously. The proposed strategy showed application potential in improving the economics of industrial glucoamylase production.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1283-1287
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• 2010

In eukaryotes, eRF3 participates in translation termination and belongs to the superfamily of GTPases. In this work, the dissociation constants for nucleosides bound to Euplotes octocarinatus eRF3 in the presence and absence of eRF1a were determined using fluorescence spectra methods. Furthermore, a GTP hydrolyzing assay of eRF3 was carried out using an HPLC method, and the kinetic parameters for GTP hydrolysis by eRF3 were determined. Consistent with data from humans, the results showed that eRF1a promoted the binding of GTP to eRF3 and the GTP hydrolyzing activity of eRF3. However, in contrast to the lack of GTP binding in the absence of eRF1 in human eRF3, the E. octocarinatus eRF3 was able to bind GTP by itself. The nucleotide binding affinity of the E. octocarinatus eRF3 also differed from the human data. A structure model and amino acid sequence alignment of potential G domains indicated that these differences may be due to valine 317 and glutamate 452 displacing the conserved glycine and lysine involved in GTP binding.