• 전자공학회논문지 IE
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• v.47 no.2
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• pp.73-81
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• 2010

The main purpose of this study was to examine the effects of meta-cognition, learning flow and problem solving ability of the college engineering students on academic achievement. For this purpose, a total of 396 college engineering freshmen of the six different departments was chosen to conduct a survey. A hypothetical model was proposed, which was composed of meta-cognition, problem solving ability and learning flow as the prediction variables, and academic achievement as the outcome variables. The results of this study through multiple regression analysis showed that meta-cognition, learning flow and problem solving ability significantly influenced on the college engineering studnets' academic achievement. In addition, learning flow was used as a significant mediated variable in the relationships among meta-cognition, problem solving ability and academic achievement. Based on these study results, the above variables investigated in this study should be considered in the design and development of the college engineering courses that enable students to facilitate their problem-solving attitude and improve academic achievement.

• Korean Journal of Childcare and Education
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• v.9 no.2
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• pp.215-238
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• 2013

This study examined the effects of mothers' rejective parenting, emotional expressivity, children's emotional regulation strategy on their social withdrawal. Participants were 223 children(121 boys, 102 girls; recruited from classes with 4-5 year olds), their mothers and 20 child care teachers. The teachers completed rating scales to measure the children's social withdrawal and emotional regulation strategies. Mothers reported their rejective parenting along with emotional expressivity. The collected data were analyzed using descriptive statistics, Pearson's productive correlation coefficient, and hierarchical multiple regressions. Results showed that mothers' rejective parenting, children's venting/support seeking strategy and avoidance/non-responsive strategy had positive relation to, whereas mother's positive expressivity were negatively related to their social withdrawal. Hierarchical regression analysis indicated that the interaction of mother's rejective parenting and positive expressivity predicted children's social withdrawal. Mother's rejective parenting was associated with children's social withdrawal, especially for children with the lowest level of mother's positive expressivity. In addition, the association between mother's rejective parenting and children's social withdrawal were partially mediated by their venting/support seeking strategy.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.70-78
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• 2009

Coptis japonica (C. japonica) is a perennial medicinal plant that has anti-inflammatory activity. C. japonica contains numerous biologically active alkaloids including berberine, palmatine, epi-berberine, and coptisine. The most well-known anti-inflammatory principal in C. japonica is berberine. For example, berberine has been implicated in the inhibition of iNOS induction by cytokines in microglial cells. However, the efficacies of other alkaloids components on microglial activation were not investigated yet. In this study, we investigated the effects of three alkaloids (palmatine, epi-berberine and coptisine) from C. japonica on lipopolysaccharide (LPS)-induced microglial activation. BV2 microglial cells were immunostimulated with LPS and then the production of several inflammatory mediators such as nitric oxide (NO), reactive oxygen species (ROS) and matrix metalloproteinase-9 (MMP-9) were examined as well as the phosphorylation status of Erk1/2 mitogen activated protein kinase (MAPK). Palmatine and to a lesser extent epi-berberine and coptisine, significantly reduced the release of NO, which was mediated by the inhibition of LPS-stimulated mRNA and protein induction of inducible nitric oxide synthase (iNOS) from BV2 microglia. In addition to NO, palmatine inhibited MMP-9 enzymatic activity and mRNA induction by LPS. Palmatine also inhibited the increase in the LPS-induced MMP-9 promoter activity determined by MMP-9 promoter luciferase reporter assay. LPS stimulation increased Erk1/2 phosphorylation in BV2 cells and these alkaloids inhibited the LPS-induced phosphorylation of Erk1/2. The anti-inflammatory effect of palmatine in LPS-stimulated microglia may suggest the potential use of the alkaloids in the modulation of neuroinflammatory responses, which might be important in the pathophysiological events of several neurological diseases including Alzheimer's disease (AD), multiple sclerosis (MS), Parkinson's disease (PD) and stroke.

• Journal of Science Education
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• v.42 no.2
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• pp.165-181
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• 2018

This study compares and analyzes the characteristics and effects of various educational contextual variables according to students' achievement level and gender groups based on the results of PISA 2015 science domain. PISA 2015 included additional variables about teaching-learning and affective characteristics in the field of science, because science was the main domain of PISA 2015. The results of the mediation analysis using a multiple group structural equation model showed that the environment and strategy for the teaching and learning had a positive effect on the affective characteristics, and also positively affected science achievement through the mediator of the affective characteristics. Particularly, the environment and strategy for the teaching and learning was the most effective in improving the affective characteristics for the low achievement group. It was found that the difference of the mediated effect between achievement level groups was statistically significant, but that between male and female students was not. Therefore, the appropriate the environment and strategy for the teaching and learning will need to be emphasized consistently to improve students' cognitive and affective achievement. The implications and suggestions of these results were discussed.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.7
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• pp.165-174
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• 2018

The purpose of this study is to verify the effects of R&D process maturity on product development performance and to verify whether R&D project performance mediating effect. The questionnaire was collected and analyzed to 131 persons related to the R&D work in 55 companies and public institutions performing R&D work. The results of this study are as follows, the effect of R&D process maturity on product development performance and mediating effect of R&D project performance were analyzed by simple and multiple regression analysis. Regression analysis was analyzed by SPSS statistical program. The higher the maturity level of the R&D process, the higher the product development performance and the R&D project performance, and the R&D project performance is partially mediated. It is concluded that it is important to establish and operate a systematic R&D process and to develop a project management methodology suitable for the characteristics of a company in order to improve product development performance. It is expected that if this study are utilized as practical R&D management methodology in corporate management, it will contribute to improvement of company product performance.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.371-377
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• 2020

The purpose of this study is to investigate the effects of satisfaction with green space on life satisfaction and to examine mediating effect of subjective health status in the relationship between satisfaction with green space and life satisfaction of older adults living in cities. For the purpose of the study, older adults aged over 65 years old who participated in 2018 Social Survey conducted by Statistics Korea were analyzed. A total of 4,567 older adults were analyzed using multiple regression analyses and significance of mediating effect was examined using bootstrapping method. Results of the analyses showed that satisfaction with green space had a significant effect on life satisfaction. Since a higher level of satisfaction with green space increased the level of life satisfaction, a direct effect of satisfaction with green space on life satisfaction was revealed. Also satisfaction with green space had a significant effect on subjective health status, so persons with a higher level of satisfaction with green space perceive their subjective health more positively. In regard to mediating effect, subjective health status partially mediated the relationship between satisfaction with green space and life satisfaction of the urban elderly. Results of this study show that green space can be used as an intervention method to improve health and life satisfaction of the urban elderly.

• Korean Journal of Social Welfare Studies
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• v.45 no.3
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• pp.237-262
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• 2014

Little is known about the relationships among adolescents'academic stress, self-efficacy, and internalization externalization. Much less is known about whether there is gender differences in the relationships. This study aims to examine (1) the effects of academic stress on internalization externalization, (2) whether self-efficacy mediates the relationships between academic stress and internalization externalization, and (3) whether there is gender difference in the relationships. For these purposes, we used Structural Equation Modeling and multi group analysis involving 2,844 middle school students participated in the Korean Youth Panel Survey. The results are as follows. First, adolescent's academic stress affected internalization externalization. Second, self-efficacy mediated the relationship between academic stress and internalization externalization. Finally, the multiple group analysis results indicated that the path coefficient between academic stress and internalization of girls was significantly greater than that of boys. Based on these results, we discussed theoretical and practical implications and suggested directions for future research on academic stress coping processes among adolescents.

• Journal of Digital Convergence
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• v.17 no.4
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• pp.1-11
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• 2019

The purpose of this study is to investigate the effects of stress, social support, and resilience on the university life as predictors of college life adjustment. For this purpose, the questionnaires were administered to 145 college students in Busan, and correlation analysis, multiple regression analysis, and mediation analysis were conducted using SPSS 18.0. The main results are as follows. First, the significant factors influencing college life adjustment were stress (B = -.351, p <.01), social support(B = -.210, p <.05) resilience (B = .355, p < .01), 30.6% explanatory power, and resilience was the most influential factor. Among the sub-factors of stress, interpersonal stress and academic stress has a negative effect. In addition, friendship support had a statistically significant effect on social support, and resilience subscale was life satisfaction and cause analysis ability. In addition, stress was found to be partly mediated in the relationship between social support and college life adjustment. Based on this study, the strategies for lowering the stress, improving the resilience of the university students in order to improve the college life adaptation were provided.

• Journal of Ginseng Research
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• v.45 no.3
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• pp.390-400
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• 2021

Background: We recently showed that gintonin, an active ginseng ingredient, exhibits antibrain neurodegenerative disease effects including multiple target mechanisms such as antioxidative stress and antiinflammation via the lysophosphatidic acid (LPA) receptors. Amyotrophic lateral sclerosis (ALS) is a spinal disease characterized by neurodegenerative changes in motor neurons with subsequent skeletal muscle paralysis and death. However, pathophysiological mechanisms of ALS are still elusive, and therapeutic drugs have not yet been developed. We investigate the putative alleviating effects of gintonin in ALS. Methods: The G93A-SOD1 transgenic mouse ALS model was used. Gintonin (50 or 100 mg/kg/day, p.o.) administration started from week seven. We performed histological analyses, immunoblot assays, and behavioral tests. Results: Gintonin extended mouse survival and relieved motor dysfunctions. Histological analyses of spinal cords revealed that gintonin increased the survival of motor neurons, expression of brain-derived neurotrophic factors, choline acetyltransferase, NeuN, and Nissl bodies compared with the vehicle control. Gintonin attenuated elevated spinal NAD(P) quinone oxidoreductase 1 expression and decreased oxidative stress-related ferritin, ionized calcium-binding adapter molecule 1-immunoreactive microglia, S100β-immunoreactive astrocyte, and Olig2-immunoreactive oligodendrocytes compared with the control vehicle. Interestingly, we found that the spinal LPA1 receptor level was decreased, whereas gintonin treatment restored decreased LPA1 receptor expression levels in the G93A-SOD1 transgenic mouse, thereby attenuating neurological symptoms and histological deficits. Conclusion: Gintonin-mediated symptomatic improvements of ALS might be associated with the attenuations of neuronal loss and oxidative stress via the spinal LPA1 receptor regulations. The present results suggest that the spinal LPA1 receptor is engaged in ALS, and gintonin may be useful for relieving ALS symptoms.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.2
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• pp.147-157
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• 2021

Coronary microembolization (CME) is associated with cardiomyocyte apoptosis and cardiac dysfunction. Puerarin confers protection against multiple cardiovascular diseases, but its effects and specific mechanisms on CME are not fully known. Hence, our study investigated whether puerarin pretreatment could alleviate cardiomyocyte apoptosis and improve cardiac function following CME. The molecular mechanism associated was also explored. A total of 48 Sprague-Dawley rats were randomly divided into CME, CME + Puerarin (CME + Pue), sham, and sham + Puerarin (sham + Pue) groups (with 12 rats per group). A CME model was established in CME and CME + Pue groups by injecting 42 ㎛ microspheres into the left ventricle of rats. Rats in the CME + Pue and sham + Pue groups were intraperitoneally injected with puerarin at 120 mg/kg daily for 7 days before operation. Cardiac function, myocardial histopathology, and cardiomyocyte apoptosis index were determined via cardiac ultrasound, hematoxylin-eosin (H&E) and hematoxylin-basic fuchsin-picric acid (HBFP) stainings, and TdT-mediated dUTP nick-end labeling (TUNEL) staining, respectively. Western blotting was used to measure protein expression related to the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase-3β (GSK-3β) pathway. We found that, puerarin significantly ameliorated cardiac dysfunction after CME, attenuated myocardial infarct size, and reduced myocardial apoptotic index. Besides, puerarin inhibited cardiomyocyte apoptosis, as revealed by decreased Bax and cleaved caspase-3, and up-regulated Bcl-2 and PI3K/Akt/GSK-3β pathway related proteins. Collectively, puerarin can inhibit cardiomyocyte apoptosis and thus attenuate myocardial injury caused by CME. Mechanistically, these effects may be achieved through activation of the PI3K/Akt/GSK-3β pathway.