• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.1
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• pp.213-227
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• 2022

Recently, research on social entrepreneurship, which simultaneously pursues social value creation and economic sustainability has increased rapidly. Researchers conducted several empirical studies, noting that social entrepreneurship is a major factor in improving the performance of social enterprises. However, most previous studies usually have limitations in measuring the performance of social enterprises based on the subjective perception of entrepreneurs, which implies the limitations of the common method bias. In addition, there is a lack of empirical evidence that can explain the specific process in which the personal characteristic of an entrepreneur, social entrepreneurship, affects the achievement of dual goals. Therefore, this study empirically investigates the effect of social entrepreneurship on performance increasing the objectivity of performance measurement and including blended value orientation(BVO), a characteristic of viewing social and economic performance as a single thing. The purpose of the study is to verify the effect of social entrepreneurship and BVO on the social and economic performance of social enterprises. We conducted regression analysis using the results of the perception survey of social enterprises in South Korea and objective performance data. As a result, risk-taking, a sub-factor of social entrepreneurship, had a positive effect on economic and social performance at a significant level. In addition, it was confirmed that social entrepreneurship improves BVO, and it affects social performance. Therefore, this study found that social entrepreneurship and BVO have a discriminatory effect on economic and social performance, respectively. This study is meaningful in that it attempted to overcome the common method bias as measuring subjectivity performance.

• Molecules and Cells
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• v.27 no.3
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• pp.279-282
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• 2009

"Two-cysteine" peroxiredoxins are antioxidant enzymes that exert a cytoprotective effect in many models of oxidative stress. However, under highly oxidizing conditions they can be inactivated through hyperoxidation of their peroxidatic active site cysteine residue. Sulfiredoxin can reverse this hyperoxidation, thus reactivating peroxiredoxins. Here we review recent investigations that have shed further light on sulfiredoxin's role and regulation. Studies have revealed sulfiredoxin to be a dynamically regulated gene whose transcription is induced by a variety of signals and stimuli. Sulfiredoxin expression is regulated by the transcription factor AP-1, which mediates its up-regulation by synaptic activity in neurons, resulting in protection against oxidative stress. Furthermore, sulfiredoxin has been identified as a new member of the family of genes regulated by Nuclear factor erythroid 2-related factor (Nrf2) via a conserved cis-acting antioxidant response element (ARE). As such, sulfiredoxin is likely to contribute to the net antioxidative effect of small molecule activators of Nrf2. As discussed here, the proximal AP-1 site of the sulfiredoxin promoter is embedded within the ARE, as is common with Nrf2 target genes. Other recent studies have shown that sulfiredoxin induction via Nrf2 may form an important part of the protective response to oxidative stress in the lung, preventing peroxiredoxin hyperoxidation and, in certain cases, subsequent degradation. We illustrate here that sulfiredoxin can be rapidly induced in vivo by administration of CDDO-TFEA, a synthetic triterpenoid inducer of endogenous Nrf2, which may offer a way of reversing peroxiredoxin hyperoxidation in vivo following chronic or acute oxidative stress.

• Journal of Preventive Medicine and Public Health
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• v.31 no.1 s.60
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• pp.27-48
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• 1998

This study was conducted to integrate the results of studies which evaluated or identified the risk factors of CVD(cerebrovascular disorders) for Koreans. We retrieved the literature published in Korean by manual search and the English literature by Medline database to identify studies on the relationship between reported risk factors and CVD conducted for the Korean from 1980 to August, 1997. Hypertension and total serum cholesterol were selected as subjects of quantitative meta-analysis on risk factors of CVD in Koreans. The overall effect sizes of the risk of CVD due to hypertension and total serum cholesterol were calculated by common odds ratio(OR) and average standardized mean difference, retrospectively. Before the integration of each effect sizes into common effect sizes, the heterogeneity tests were conducted. Also, sensitivity tests were conducted for the estimated common effect sizes. Regarding hypertension and CVD, a total of 9 epidemiologic studies were identified with a total of 2,271 cases of CVD. The overall OR of hypertension associated CVD was 4.10(95% confidence interval[CI] 3.56 to 4.71). The OR of hypertension associated with hemorrhagic CVD and ischemic CVD were 6.56(95% CI : 4.92 to 8.80) and 3.28 (95% CI : 2.77 to 3.90), retrospectively. The OR of hypertension in relation to hemorrhagic CVD was significantly higher than that of hypertension in relation to overall CVD or ischemic CVD. Regarding total serum cholesterol and ischemic CVD, total 9 epidemiologic studies were identified with a total of 843 cases of ischemic CVD. Average mean difference as an effect size was 0.76, which was judged an important value according to Cohen's criteria. Our data suggested that hypertension was an important risk factor of overall CVD and its subtypes, and that the total serum cholesterol was associated with ischemic CVD in Koreans. For the lack of reliable prospective studies, however, we concluded that further research designed longitudinally would be required in this area.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.22-33
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• 2016

The purposes of this study were to examine the characteristics of friendship among the elderly, particularly the relationships between the functions of friendship, the degree of satisfaction with friendship, and subjective well-being. Written questionnaires completed by 244 the new-elderly(95men, mean age 60.02 years/ 149women, mean 62.04 years) were analyzed. As a result, the main findings of our study were: First, Among men, the duration of friendship was longer than among women. The most common initial acquaintance among men were co-workers, followed by schoolmates and old playmates, while friends made through leisure and volunteer activities or in the neighborhood were more common for women. Second, Factor analysis revealed the following two factors: 'trust and support', and 'companionship'. Among both men and women, the degree of satisfaction with friendship was positively correlated with subjective well-being, and the study suggested that the level of 'trust and support' influenced the degree of satisfaction with friendship. And expand the scale, because the future looked at the gender gap in the center is considered that there is a need for comparative studies specific age groups.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.7 s.238
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• pp.921-929
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• 2005

This paper presents an accelerated life test for burnout of tungsten filament of incandescent lamp. From failure analyses of field samples, it is shown that their root causes are local heating or hot spots in the filament caused by tungsten evaporation and wire sag. Finite element analysis is performed to evaluate the effect of vibration and impact for burnout, but any points of stress concentration or structural weakness are not found in the sample. To estimate the burnout life of lamp, an accelerated life test is planned by using quality function deployment and fractional factorial design, where voltage, vibration, and temperature are selected as accelerating variables. We assumed that Weibull lifetime distribution and a generalized linear model of life-stress relationship hold through goodness of fit test and test for common shape parameter of the distribution. Using accelerated life testing software, we estimated the common shape parameter of Weibull distribution, life-stress relationship, and accelerating factor.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2018-2030
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• 2015

A two stage ac drive configuration consisting of a single-phase line commutated rectifier and a three-phase voltage source inverter (VSI) is very common in low and medium power applications. The deterministic pulse width modulation (PWM) methods like sinusoidal PWM (SPWM) could not be considered as an ideal choice for modern drives since they result mechanical vibration and acoustic noise, and limit the application scope. This is due to the incapability of the deterministic PWM strategies in sprawling the harmonic power. The random PWM (RPWM) approaches could solve this issue by creating continuous harmonic profile instead of discrete clusters of dominant harmonics. Insufficient filtering at dc link results in the amplitude distortion of the input dc voltage to the VSI and has the most significant impact on the spectral errors (difference between theoretical and practical spectra). It is obvious that the sprawling effect of RPWM undoubtedly influenced by input fluctuation and the discrete harmonic clusters may reappear. The influence of dc link fluctuation on harmonics and their spreading effect in the VSI remains invalidated. A case study is done with four different filter capacitor values in this paper and results are compared with the constant dc input operation. This paper also proposes an ingenious RPWM, a ripple dosed sinusoidal reference-random carrier PWM (RDSRRCPWM), which has the innate capacity of suppressing the effect of input fluctuation in the output than the other modern PWM methods. MATLAB based simulation study reveals the fundamental component, total harmonic distortion (THD) and harmonic spread factor (HSF) for various modulation indices. The non-ideal dc link is managed well with the developed RDSRRCPWM applied to the VSI and tested in a proto type VSI using the field programmable gate array (FPGA).

• Journal of Periodontal and Implant Science
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• v.42 no.1
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• pp.3-12
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• 2012

Purpose: Anti-rheumatic agents target common molecular pathways of inflammation in rheumatoid arthritis (RA) and periodontitis. The purpose of this study was to determine the relative effect of anti-rheumatic agents on the levels of inflammatory biomarkers and periodontal inflammation in RA patients with periodontitis. Methods: A systematic review and meta-analysis were conducted of studies comparing periodontal parameters of inflammation, such as bleeding on probing, and biomarkers of inflammation in RA patients with periodontitis and healthy adults with and without periodontitis. The search included the electronic databases MEDLINE, Cochrane Database of Systematic Reviews, and Google Scholar, inclusive through October 2011, with no language restrictions. Hand searches were conducted of the bibliographies of related journals and systematic reviews. Observational and interventional studies assessing the effects of antirheumatic therapy qualified for inclusion. Two reviewers performed independent data extraction and risk-of-bias assessment. Of the 187 identified publications, 13 studies fulfilled the inclusion criteria. Results: When compared to healthy adults without periodontitis, RA subjects were found to have significantly higher levels of bleeding on probing and limited evidence of higher levels of interleukin-$1{\beta}$ and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in gingival crevicular fluid and saliva. No consistent differences were found in periodontal parameters and inflammatory biomarkers between RA subjects and adults with periodontitis. Studies evaluating the effect of anti-TNF-${\alpha}$ therapy in RA subjects with periodontitis have yielded inconsistent results. Conclusions: There are limited data, however, to suggest that anti-TNF-${\alpha}$ agents can reduce local production of inflammatory cytokines and periodontal inflammation in RA patients with periodontitis.

• Journal of Neurogastroenterology and Motility
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• v.24 no.4
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• pp.669-675
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• 2018

Background/Aims Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are common gastrointestinal (GI) disorders and these patients frequently overlap. Trimebutine has been known to be effective in controlling FD co-existing diarrhea-dominant IBS, however its effect on overlap syndrome (OS) patients has not been reported. Therefore, we investigated the effect of trimebutine on the model of OS in guinea pigs. Methods Male guinea pigs were used to evaluate the effects of trimebutine in corticotropin-releasing factor (CRF) induced OS model. Different doses (3, 10, and 30 mg/kg) of trimebutine were administered orally and incubated for 1 hour. The next treatment of $10{\mu}g/kg$ of CRF was intraperitoneally injected and stabilized for 30 minutes. Subsequently, intragastric 3 mL charcoal mix was administered, incubated for 10 minutes and the upper GI transit analyzed. Colonic transits were assessed after the same order and concentrations of trimebutine and CRF treatment by fecal pellet output assay. Results Different concentrations (1, 3, and $10{\mu}g/kg$) of rat/human CRF peptides was tested to establish the OS model in guinea pigs. CRF $10{\mu}g/kg$ was the most effective dose in the experimental OS model of guinea pigs. Trimebutine (3, 10, and 30 mg/kg) treatment significantly reversed the upper and lower GI transit of CRF induced OS model. Trimebutine significantly increased upper GI transit while it reduced fecal pellet output in the CRF induced OS model. Conclusions Trimebutine has been demonstrated to be effective on both upper and lower GI motor function in peripheral CRF induced OS model. Therefore, trimebutine might be an effective drug for the treatment of OS between FD and IBS patients.

• East Asian Journal of Business Economics (EAJBE)
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• v.6 no.2
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• pp.1-13
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• 2018

Purpose - The present research is to investigate the effect of psychological empowerment on turnover intention through job satisfaction and organizational commitment. Research design, data, and methodology - These include turnover intention as dependent variable, psychological empowerment as an independent variable and for mediating variables job satisfaction and organizational commitment. Also nationality of employee is used as a moderating variable. Survey data was collected was total 886 respondents from 345 Korean, 313 Chinese, 228 Japanese. Data analysis was conducted with SPSS to test reliability of variables with Cronbach's alpha and one variable confirmatory factor analysis to test common method bias. And regression analysis was conducted to confirm relationship among variables. AMOS was used for path analysis and to analysis moderating effect of employees' country. Results - The results of regression indicate that psychological empowerment increase job satisfaction, affective commitment, normative commitment and turnover intention. Job satisfaction, affective commitment and normative commitment decrease turnover intention. As for the moderating role of country, it seems that country does matter. Conclusions - Main conclusions of this research implicate that to decrease employee turnover intention company need to manage psychological empowerment, job satisfaction, and organizational commitment. Also there is need to consider similarity and difference in managing employees of Korea, China and Japan employees. Manager need to verify direction and importance of each antecedent then apply to employees.

• Korean Journal of Health Education and Promotion
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• v.7 no.1
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• pp.1-9
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• 1990

This paper discusses a new perspective in health approach and the effect of health life on health status, and suggests some points to be improved in the establishment of health policies hereafter. Today's health problems changed from the acute epidemic diseases caused by simple factor to the multifactorial chronic diseases. Therefore, the health approach tries the holistic health approach, that is, the integrative approach by the interdisciplinary cooperation. With the advent of holistic health and holistic medicine in 1970's, the behavioral medicine was born in 1977, which is the interdisciplinary field concerned with the development and integration of behavioral and biomedical science knowledge and techniques relevent to prevention, diagnosis and treatment. As a means to the reducement of the unnecessary medical utilization and medical expense, the medical self care and self-help movement is well under way in the countries of America, England, and Canada, in which lay persons are encouraged to actively function for themselves to prevent, detect and treat common illnesses and to promote positive health habits through the health activation programs such as The Course for Activated Patients and The Health Activated Person. This study shows that the individual health life gives great positive effect to his health status with the reducement of medical expense. These above facts suggest that the preventive health programs such as health education should be developed and strengthened instead of medical care-oriented health policy.