• International Journal of Knowledge Content Development & Technology
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• v.8 no.4
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• pp.33-53
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• 2018

Since business startups are known to have positive effects on the economic growth of a country, it is necessary to review the factors influencing the willingness to start new businesses for the people to act on business startups. In this regard, the study sought to reexamine the findings of previous research showing that the innovative, initiative, and risk-taking characteristics, which are the constitutive elements of entrepreneurships, influence the willingness to start up. Furthermore, in this study, attempts were made to empirically analyze the direct and indirect relationships of self-leadership influencing the willingness to start new businesses. Consequently, first, it showed that college students' entrepreneurship has positive effects on the willingness to start new businesses. Second, the significance of the gender of college students was not confirmed as to playing a regulating role in the relationship between entrepreneurship and the willingness to start up. Third, the relationship between self-leadership and the willingness to start new businesses was validated to be significant in a positive direction. Fourth, no mediating effect of self-leadership in the relationship between entrepreneurship and the willingness to start new businesses was observed. Such research results have the following significances. First, while there is an awareness that the concepts of business start- up, entrepreneurship, and leadership carry masculinity, the lack of regulating effect of gender may reflect the changing phases of time and society where women's participation has been increasing. Second, self-leadership is a concept by which one pioneers his or her own life and an influencing factor on the willingness to start up; however, since it has enormous impacts on the entrepreneurship and willingness to start up, relevant mediating effects were not observed and the magnitude of the important influence between entrepreneurship and the willingness to start up were confirmed.

• Journal of Ginseng Research
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• v.46 no.6
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• pp.809-818
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• 2022

Background: The non-saponin fraction (NSF) of Korean Red Ginseng is a powder in which saponin is eliminated from red ginseng concentrate by fractionation. In this study, we examined the effect of NSF on age-associated sarcopenia in old mice. Methods: NSF (50 or 200 mg/kg/day) was administered orally daily to young (3-6-month-old) and old (20-24-month-old) C57BL/6 J mice for 6 weeks. Body weight and grip strength were assessed once a week during the oral administration period. The gastrocnemius and quadriceps muscle were excised, and the muscle fiber size was compared through hematoxylin and eosin staining. In addition, the effect of NSF on sarcopenia and inflammation/oxidative stress-related factors in hindlimb muscles was investigated by western blotting. Flow cytometry analysis was conducted to investigate the effect of NSF on immune homeostasis. Blood samples were collected by cardiac puncture, and the serum levels of insulin-like growth factor 1, pro-inflammatory cytokines, and glutathione were evaluated. Results: NSF significantly alleviated muscle strength, mass, and also fiber size in old mice. Age-associated impairment of immune homeostasis was recovered by NSF through retaining CD11b⁺F4/80⁺ macrophages and regulating inflammatory biomarkers. NSF also decreased the age-induced expression of oxidative stress factors. Taken together, NSF showed the effect of improving sarcopenia by inhibiting low-grade chronic inflammatory/oxidative stress factors. Conclusion: NSF exhibited anti-sarcopenia effects by regulating chronic inflammation and oxidative stress in old mice. Thus, we suggest that NSF is a promising restorative agent that can be used to improve sarcopenia in the elderly as well as maintain immune homeostasis.

• IMMUNE NETWORK
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• v.9 no.3
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• pp.98-105
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• 2009

Background: It has been recently noticed that type 2 diabetes (T2D), one of the most common metabolic diseases, causes a chronic low-grade inflammation and activation of the innate immune system that are closely involved in the pathogenesis of T2D. Cordyceps militaris, a traditional medicinal mushroom, produces a component compound, cordycepin (3'-deoxyadenosine). Cordycepin has been known to have many pharmacological activities including immunological stimulating, anti-cancer, and anti-infection activities. The molecular mechanisms of cordycepin in T2D are not clear. In the present study, we tested the role of cordycepin on the anti-diabetic effect and anti-inflammatory cascades in LPS-stimulated RAW 264.7 cells. Methods: We confirmed the levels of diabetes regulating genes mRNA and protein of cytokines through RT-PCR and western blot analysis and followed by FACS analysis for the surface molecules. Results: Cordycepin inhibited the production of NO and pro-inflammatory cytokines such as IL-$1{\beta}$, IL-6, and TNF-${\alpha}$ in LPS-activated macrophages via suppressing protein expression of pro-inflammatory mediators. T2D regulating genes such as $11{\beta}$-HSD1 and PPAR${\gamma}$ were decreased as well as expression of co-stimulatory molecules such as ICAM-1 and B7-1/-2 were also decreased with the increment of its concentration. In accordance with suppressed pro-inflammatory cytokine production lead to inhibition of diabetic regulating genes in activated macrophages. Cordycepin suppressed NF-${\kappa}B$ activation in LPS-activated macrophages. Conclusion: Based on these observations, cordycepin suppressed T2D regulating genes through the inactivation of NF-${\kappa}B$ dependent inflammatory responses and suggesting that cordycepin will provide potential use as an immunomodulatory agent for treating immunological diseases.

• Journal of Microbiology and Biotechnology
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• v.31 no.6
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• pp.867-874
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• 2021

Epalrestat (EPS) is a brain penetrant aldose reductase inhibitor, an approved drug currently used for the treatment of diabetic neuropathy. At near-plasma concentration, EPS induces glutathione biosynthesis, which in turn reduces oxidative stress in the neuronal cells. In this study, we found that EPS reduces neurodegeneration by inhibiting reactive oxygen species (ROS)-induced oxidative injury, mitochondrial membrane damage, apoptosis and tauopathy. EPS treatment up to 50 µM did not show any toxic effect on SH-SY5Y cell line (neuroblastoma cells). However, we observed toxic effect at a concentration of 100 µM and above. At 50 µM concentration, EPS showed better antioxidant activity against H₂O₂ (100 µM)-induced cytotoxicity, ROS formation and mitochondrial membrane damage in retinoic acid-differentiated SH-SY5Y cell line. Furthermore, our study revealed that 50 µM of EPS concentration reduced the glycogen synthase kinase-3 β (GSK3-β) expression and total tau protein level in H₂O₂ (100 µM)-treated cells. Findings from this study confirms the therapeutic efficacy of EPS on regulating Alzheimer's disease (AD) by regulating GSK3-β and total tau proteins phosphorylation, which helped to restore the cellular viability. This process could also reduce toxic fibrillary tangle formation and disease progression of AD. Therefore, it is our view that an optimal concentration of EPS therapy could decrease AD pathology by reducing tau phosphorylation through regulating the expression level of GSK3-β.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.578-585
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• 2020

The purpose of this study was to investigate the Effects of Happiness on Organizational Commitment According to the Socio-demographic Characteristics of Teachers of Infants and Toddlers. The study subjects were 167 infant teachers in Ulsan. The collected data were analyzed through frequency analysis, reliability analysis and correlation analysis on SPSS 22.0 program, and multiple regression analysis was conducted for the causal relation between variables. The analysis results revealed that self-regulating happiness, a sub-factor of happiness of infant teachers, had a significant effect on their affective commitment, but factors of internal and external happiness did not significantly affect affective commitment. Second, self-regulating happiness had a significant effect on their continuance commitment. Third, the self-regulating happiness had a significant effect on their normative commitment. This study is considered to provide the basic data for preparing a practical intervention plan for improving the organizational commitment of infant teachers.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.6
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• pp.501-508
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• 2019

Rosmarinic acid (RA) is a natural polyphenolic compound that exists in many medicinal species of Boraginaceae and Lamiaceae. The previous studies have revealed that RA had therapeutic effects on hepatocellular carcinoma (HCC) in the H22-xenograft models by inhibiting the inflammatory cytokines and $NF-{\kappa}B$ p65 pathway in the tumor microenvironment. However, its molecular mechanisms of immunoregulation and pro-apoptotic effect in HCC have not been fully explored. In the present study, RA at 75, 150, and 300 mg/kg was given to H22 tumor-bearing mice via gavage once a day for 10 days. The results showed that RA can effectively inhibit the tumor growth through regulating the ratio of $CD4^+/CD8^+$ and the secretion of interleukin (IL)-2 and interferon-${\gamma}$, inhibiting the expressions of IL-6, IL-10 and signal transducer and activator of transcription 3, thereby up-regulating Bax and Caspase-3 and down-regulating Bcl-2. The underlying mechanisms involved regulation of immune response and induction of HCC cell apoptosis. These results may provide a more comprehensive perspective to clarify the anti-tumor mechanism of RA in HCC.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.1
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• pp.17-25
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• 2008

To achieve the unidirectional airflow in a cleanroom, we need to predict accurately the static pressure losses at the lower plenum and to control properly the opening pressure ratio of access floor panels based on these pressure losses. At first, the present study proposed a correlation to predict the velocity distribution at the lower plenum, because the accuracy to predict pressure losses at the lower plenum depends on how to calculate the velocity correctly against the inner structures at the lower plenum. In the second place, this study proposed correlations which considered the effect of inner structures such as columns, ducts and equipments at the lower plenum on pressure losses. In order to test the accuracy of these correlations, we compared air flow patterns before regulating the opening ratio of access floor with those after regulating. Results after regulating the opening ratio of access floor show good unidirectional uniform airflow pattern. So the present method can be used as an important tool to control the air flow in a cleanroom.

• Korean journal of communication and information
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• v.37
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• pp.43-72
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• 2007

This article is media education uses type of a middle high school students and research about effect that is taking media education. Measured media education uses motivation, studies own effect academic self-efficacy, media competence and school achievement for this research. As analysis result, priority media education uses motive was 'teaching convenience/help sought', 'Information/education method picking up sought', 'new teaching/communication thoroughgoing sought', 'ability elevation pursuit', 'self-regulating education sought', 'up-to-dateness sought', 'New knowledge/education sought' of order. By next time, only 'new knowl edge/education sought' motive caused positive effect in studies own effect among media education uses motive. Among media education uses motive, 'teaching convenience/help sought', 'Information/education method picking up sought', 'New study/communication thoroughgoing sought', 'self-regulating education sought', 'up-to-dateness sought' motive caused positive effect in media competence. Also, it caused positive effect among media education uses motive 'self-regulating education sought' and 'new knowledge/education sought' in students' school achievement. Finally, 'academic self-efficacy' is 'media competence' more in school achievement influence. Media education influenced new teaching method and ability elevation to some students. But, academic self-efficacy and school achievement did not cause big effect students. However, media education influenced in some students' media competence elevation.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.1
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• pp.62-69
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• 2021

This study aimed to verify the suitability of an air quality regulating service for wetland ecosystem service evaluation by investigating the effect of reducing particulate matter (PM) on vegetation in wetlands. We installed tunnel-type experimental plots at Yonghwasil Pond in the National Institute of Ecology and set up the input and output of PM by applying the natural vegetation of the relevant wetlands. We took measurements by replicating four different conditions four times each. The air quality regulating service in each experimental plot was measured based on PM10 concentration; further, the difference between the input and the output concentration of PM passing through the Phragmites australis community tunnel was measured using a light scattering method. For the Phragmites australis community in the outdoor conditions and bare land, the PM concentration was measured with the same specifications as tunnel-type experimental plots without setting up the input and output. For the tunnel-type experimental plots, PM10 concentration was significantly lower in the output than in the input. Furthermore, in the outdoor conditions, a comparison between the Phragmites australis community and bare land showed that the concentration was relatively low in the former than in the latter. This confirmed the PM reducing effect due to the blockage and absorption of PM depending on the growth of Phragmites australis. Based on the results of this study, we assessed the air quality regulating service in wetlands as an evaluation indicator.

• IMMUNE NETWORK
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• v.22 no.3
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• pp.21.1-21.21
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• 2022

As far the current severe coronavirus disease 2019 (COVID-19), respiratory disease is still the biggest threat to human health. In addition, infectious respiratory diseases are particularly prominent. In addition to killing and clearing the infection pathogen directly, regulating the immune responses against the pathogens is also an important therapeutic modality. Sirtuins belong to NAD+-dependent class III histone deacetylases. Among 7 types of sirtuins, silent information regulator type-1 (SIRT1) played a multitasking role in modulating a wide range of physiological processes, including oxidative stress, inflammation, cell apoptosis, autophagy, antibacterial and antiviral functions. It showed a critical effect in regulating immune responses by deacetylation modification, especially through high-mobility group box 1 (HMGB1), a core molecule regulating the immune system. SIRT1 was associated with many respiratory diseases, including COVID-19 infection, bacterial pneumonia, tuberculosis, and so on. Here, we reviewed the latest research progress regarding the effects of SIRT1 on immune system in respiratory diseases. First, the structure and catalytic characteristics of SIRT1 were introduced. Next, the roles of SIRT1, and the mechanisms underlying the immune regulatory effect through HMGB1, as well as the specific activators/inhibitors of SIRT1, were elaborated. Finally, the multitasking roles of SIRT1 in several respiratory diseases were discussed separately. Taken together, this review implied that SIRT1 could serve as a promising specific therapeutic target for the treatment of respiratory diseases.