• Journal of the Korean Society of Radiology
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• v.18 no.1
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• pp.45-52
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• 2024

In this study, an AI-based algorithm was developed to prevent image quality deterioration and reading errors due to patient movement in PET/CT examinations that use radioisotopes in medical institutions to test cancer and other diseases. Using the Mothion Free software developed using, we checked the degree of correction of movement due to breathing, evaluated its usefulness, and conducted a study for clinical application. The experimental method was to use an RPM Phantom to inject the radioisotope 18F-FDG into a vacuum vial and a sphere of a NEMA IEC body Phantom of different sizes, and to produce images by directing the movement of the radioisotope into a moving lesion during respiration. The vacuum vial had different degrees of movement at different positions, and the spheres of the NEMA IEC body Phantom of different sizes produced different sizes of lesions. Through the acquired images, the lesion volume, maximum SUV, and average SUV were each measured to quantitatively evaluate the degree of motion correction by Motion Free. The average SUV of vacuum vial A, with a large degree of movement, was reduced by 23.36 %, and the error rate of vacuum vial B, with a small degree of movement, was reduced by 29.3 %. The average SUV error rate at the sphere 37mm and 22mm of the NEMA IEC body Phantom was reduced by 29.3 % and 26.51 %, respectively. The average error rate of the four measurements from which the error rate was calculated decreased by 30.03 %, indicating a more accurate average SUV value. In this study, only two-dimensional movements could be produced, so in order to obtain more accurate data, a Phantom that can embody the actual breathing movement of the human body was used, and if the diversity of the range of movement was configured, a more accurate evaluation of usability could be made.

• Food Science and Preservation
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• v.30 no.1
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• pp.109-121
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• 2023

This study was conducted to evaluate vitamin D intake of Koreans in a total diet study (TDS) and to determine the effect of irradiation on vitamin D synthesis in mushrooms. For analysis, sample were saponified and extracted with hexane, and vitamin D was quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on the validation results, the recovery of the National Institute of Standards and Technology (NIST) standard reference sample (SRM) 1849a was 96.7% and the z-score of -1.6 was obtained by the Food Analysis Performance Assessment Scheme (FAPAS) proficiency test (PT) 21115. Vitamin D₂ was not detected in any samples, and the highest level of vitamin D₃ was detected in mackerel and anchovies ranging from 24.2 to 120.2 ㎍/kg. The mean daily intake of vitamin D was 0.99 ㎍/day, as estimated from the vitamin D contents of the analyzed foods and their corresponding intake. The adequate intake (AI) of vitamin D based on the Dietary reference intakes for Koreans provided by the Ministry of Health and Welfare is 5-15 ㎍/day for Koreans aged 6 to 75 years. Compared with this AI, vitamin D intake of Koreans estimated in this study was inadequate. For that, the increased vitamin D content in ultraviolet (UV)/sun light irradiated mushrooms warrants further research to increase vitamin D intake of Koreans through diet.

• Information Systems Review
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• v.18 no.3
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• pp.209-233
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• 2016

Internet companies that utilize social network have increased in number. The introduction of diverse social media services facilitated innovative changes in e-business. Social network service (SNS), which is a domain of social media, is a web-based service designed to strengthen human relations in the Internet and build new social relations. The remarkable growth of social network services and the profit generation and perception of this service are the new growth engines of this digital age. Given this development, many global IT companies views SNS as the most powerful form of social media. Thus, they invest efforts to develop business models using SNS.2) This study verifies the impact of privacy exposure in SNS as a result of privacy invasion. This study examines the purpose of using the SNS and user's awareness of the significance of personal information, which are key factors that affect self-disclosure of personal information. This study utilizes theory of reasoned action (TRA) to provide a theoretical platform that describes the specific behavior and emotional response of individuals. This study presents a research model that considers negative attitude (negatude). In this model, self-disclosure in SNS is considered a TRA. TRA is a subjective norm, a behavioral intention, and a key variable of exposure behavior. A survey was conducted on college students at Y university in Seoul to empirically verify the research model. The students have experiences in using SNS. A total of 198 samples were collected. Path analysis was applied to analyze the relations of factors. The results of path analysis show the statistically insignificant impact of privacy invasion on negatude, subjective norm, behavioral intention, and exposure behavior. The impact of unrecognized privacy invasion was also considered insignificant. The impacts of intention to use SNS on negatude, subjective norm, behavioral intention, and exposure behavior was significant. A significant impact was also found for the significance of personal information on subjective norm, behavioral intention, and exposure behavior, whereas the impact on negatude was insignificant. The impact of subjective norm on behavioral intention was significant. Lastly, the impact of behavioral intention on exposure behavior was insignificant. These findings are significant because the study examined the process of self-disclosure by integrating psychological and social factors based on theoretical discussion.

• Research in Plant Disease
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• v.29 no.4
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• pp.384-389
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• 2023

Milling can affect the distribution of mycotoxins in small grains. To investigate the effects on barley, seven hulled barley and three naked barley samples naturally contaminated with trichothecenes and zearalenone were obtained and milled at commonly used rates. Both barleys were simultaneously contaminated with deoxynivalenol and its acetyl derivatives (98.1-2,197.8 ㎍/kg), nivalenol and its acetyl derivative (468.5-3,965.1 ㎍/kg), and zearalenone (4.1-274.2 ㎍/kg). Milling hulled barleys at a rate of 67% reduced the mycotoxins in the grain by 90.9% for deoxynivalenol, 87.7% for nivalenol, and 93.2% for zearalenone. The reduction in naked barleys (milled at a rate of 70%) was slightly lower than in hulled barleys, with 88.6% for deoxynivalenol, 80.2% for nivalenol, and 70.1% for zearalenone. In both barleys, the acetyl derivatives of deoxynivalenol and nivalenol were reduced by 100%. However, barley bran had significantly higher mycotoxin concentrations than the pre-milled grains: bran from hulled barley had a 357% increase in deoxynivalenol, 252% increase in nivalenol, and 169% increase in zearalenone. Similarly, bran from naked barley had a 337% increase in deoxynivalenol, 239% increase in nivalenol, and 554% increase in zearalenone. These results show that mycotoxins present in the outer layers of barley grain can be effectively removed through the milling process. As milling redistributes mycotoxins from the grain into the bran, however, it shows that advance monitoring of barley bran is recommended when using barley bran for human or animal consumption.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.447-454
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• 2023

In the environment in which humans live, there are various antigens that invade the human body and interfere with humans leading a healthy life, so the immune system recognizes the antigen then removes them through a complex mechanism. Macrophages are widely distributed immune cells involved in the innate immune system, and produce various immune modulators such as inducible nitric oxide synthase-induced nitric oxide, cyclooxygenase-2 induced prostaglandin E2 and proinflammatory cytokines such as tumor necrosis factor-alpha. On the other hand, Protaetia brevitarsis seulensis larvae are a type of edible insect that have emerged as an alternative to the future food supply problem. The immuno-modulatory effect through the activation of murine macrophage RAW264.7 cell via mitogen-activated protein kinases (MAPKs)/nuclear factor-kappa B (NF-κB) signaling pathways has been reported. Based on this report, in this study, we confirmed how the expression of immune modulators induced by Protaetia brevitarsis seulensis larvae extracts in RAW264.7 cells was changed by treatment with pharmacological inhibitors of toll-like receptor 4 (TLR4), MAPKs and NF-κB signaling pathways. As a result, reduction of immune modulators was confirmed in the c-Jun N-terminal kinase (JNK) inhibitor treatment group and NF-κB inhibitor treatment group among the Protaetia brevitarsis seulensis larvae-treated RAW264.7 cell. Furthermore, in the TLR4 inhibitor-treated group, decreases in phosphorylation of JNK and NF-κB factors were confirmed in Protaetia brevitarsis seulensis larvae-treated RAW264.7 cell, as well as decreases in immune modulators. This results suggest that Protaetia brevitarsis seulensis larvae activates RAW264.7 cells by the engagement of TLR4-JNK/NF-κB signaling pathway.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.416-423
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• 2023

Figs has known to have antioxidant, whitening, anti-inflammatory, and antibacterial effects in their leaves, roots, stems, latex, and fruits. In order to develop cosmetic materials based on natural products, we have studied on the skin activity of the ficin in latex as well as the whitening function of the fruit extract with 70% ethanol, and used it as a raw material for released cosmetic product. However, there is little research on the demand for the development of new eutectic solvent extraction methods and its ability to control skin inflammation and psoriasis regulation. Thus, in this study, we evaluated the effectiveness of fig fruit extracts and fractions using eutectic solvent extraction for skin inflammation control and psoriasis. First, fig fruits were extracted under optimal eutectic solvent conditions and fractionated with n-hexane, dichloromethane, ethyl acetate, and butanol. First, the antioxidant activity and inhibition of nitric oxide (NO) production were confirmed in mouse macrophage RAW264.7 cells. In addition, as a result of observing the mRNA expression through RT-PCR, pro-inflammatory cytokines such as TNF-α, IL1α, and IL-1β were suppressed significantly in the hexane, dichloromethane, and ethyl acetate fractions. In addition, it was confirmed in TNF-α stimulated HaCaT keratinocyte model. Finally, chemokine CC motif ligand 20 (CCL20), marker gene of human psoriasis skin disease, was significantly suppressed in the hexane, dichloromethane, and ethyl acetate fractions. These results suggested its anti-inflammatory and skin soothing effect and the possibility of development as an excellent skin soothing natural cosmetic material in the future through future clinical trials.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.3
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• pp.139-153
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• 2024

The importance of sustainable growth and cost reduction has increased globally, leading to the expansion of outsourcing by companies. Additionally, the spread of the platform economy has brought changes in the way we work, and the online outsourcing market, where tasks are mediated through platforms, is growing. Academically, while research on general outsourcing is actively conducted, studies on online outsourcing are relatively insufficient compared to its actual utilization. This study aims to analyze the factors and performance factors of online outsourcing utilization by startups, to identify the effects and concerns of using online outsourcing from multiple perspectives, and to suggest the roles of various stakeholders for effective utilization and industry development. For the research, a survey was conducted with 281 employees of startups who have experience in using online outsourcing, and the main findings are as follows. First, the enhancement of efficiency, profitability, and innovation through the use of online outsourcing positively affects organizational commitment and job satisfaction of startup members. Especially, the improvement of efficiency due to the use of online outsourcing has a significant effect on enhancing job satisfaction. Second, concerns about the burden of online outsourcing fees or uncertain outcomes negatively affect organizational commitment and job satisfaction. Third, there are perceptual differences in the motivations and performance regarding the utilization of online outsourcing depending on the job position. Practitioners perceive that the use of online outsourcing increases organizational commitment, whereas managers have relatively higher concerns about the uncertainty of outsourced task outcomes and information security. Through this study, the possibility that human resource shortages and employee management issues in startups can be improved through online outsourcing was confirmed. By verifying the influence of various factors of online outsourcing utilization, this study also provides meaningful implications for establishing business strategies for online outsourcing intermediary platform companies and for formulating startup support policies by government and other startup support organizations.

• Journal of Life Science
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• v.34 no.8
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• pp.558-566
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• 2024

The potential therapeutic effects of Kaempferia Parviflora ethanol extract (KPE) on osteoarthritis were investigated using the human chondrocyte cell line (CHON-001) to explore its application in functional foods. The CHON-001 cells were pre-treated with either 1 ㎍/ml or 5 ㎍/ml of KPE before exposure to 10 ng/ml of IL-1β to induce osteoarthritis. Results showed that KPE treatment significantly suppressed IL-1β-induced TNF-α production by 66% and 50% at concentrations of 1 ㎍/ml and 5 ㎍/ml KPE, respectively. In addition, COX-2 protein expression was reduced by 26% and 34% compared to control levels. The preservation of chondrocyte-specific matrix proteins, aggrecan, and collagen type II, was notable, with aggrecan and mRNA levels maintained by 5% and 8%, and collagen II levels preserved by 62% and 47% at the same KPE concentrations. This preservation is likely due to the reduced expression of MMP1 and MMP13, enzymes responsible for matrix protein degradation. Overall, the current results suggest that KPE may protect chondrocytes from IL-1β-induced osteoarthritis by suppressing TNF-α production and COX-2 expression while preserving critical matrix proteins like aggrecan and collagen II by suppressing the expressions of their degrading enzymes (MMP-1 and MMP-13). Therefore, KPE holds promise as a candidate for developing functional foods aimed at reducing osteoarthritis.

• Journal of Life Science
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• v.34 no.9
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• pp.609-619
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• 2024

Neurodegenerative diseases are marked by the accumulation of toxic misfolded proteins in neurons. Therefore, strategies for the effective prevention and clearance of aggregates are crucial for therapeutic interventions. Cytoplasmic dynein plays a crucial role in the clearance of aggregates by transporting them to the cell center, where lysosomes are enriched and the aggregates undergo extensive autophagic degradation. Previously, we reported evidence for the activation of dynein by N-acetylglucosamine kinase (NAGK) and Reln. In the present study, we explored the effects of NAGK and Reln upregulation on the clearance of aggregates. To upregulate NAGK and Reln genes in HEK293T cells (a human embryonic kidney cell line), CRISPR/dCas9 activation systems (CASs) were used with specific plasmids encoding target-specific 20 nt guide RNA. The effects of this genetic modulation were analyzed in Huntington's disease cellular models, including HEK293T cells and primary mouse cortical cells, where external mutant huntingtin (mHtt, Q74) aggregates were induced. The results showed that the CAS activation of NAGK or Reln, or their combination, significantly reduced the proportion of cells with Q74 aggregates (aggresomes). This effect was reversed by Ciliobrevin D (a dynein inhibitor) and chloroquine (an autophagy inhibitor), indicating the role of dynein-mediated autophagy in aggregate clearance. These findings provide the basis for therapeutic strategies aimed at enhancing neuronal health through targeted gene activation.

• Journal of Distribution Research
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• v.15 no.1
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• pp.49-71
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• 2010

Franchise businesses in South Korea have contributed to economic growth and job creation, and its growth potential remains very high. However, despite such virtues, domestic franchise businesses face many problems such as the instability of franchisor's business structure and weak financial conditions. To solve these problems, the government enacted legislation and strengthened franchise related laws. However, the strengthening of laws regulating franchisors had many side effects that interrupted the development of the franchise business. For example, legal regulations regarding franchisors have had the effect of suppressing the franchisor's leadership activities (e.g. activities such as the ability to advocate the franchisor's policies and strategies to the franchisees, in order to facilitate change and innovation). One of the main goals of the franchise business is to build cooperation between the franchisor and the franchisee for their combined success. However, franchisees can refuse to follow the franchisor's strategies because of the current state of franchise-related law and government policy. The purpose of this study to explore the effects of franchisor's leadership style on franchisee's commitment in a franchise system. We classified leadership styles according to the path-goal theory (House & Mitchell, 1974), and it was hypothesized and tested that the four leadership styles proposed by the path-goal theory (i.e. directive, supportive, participative and achievement-oriented leadership) have different effects on franchisee's commitment. Another purpose of this study to explore the how the level of franchisee's self-efficacy influences both the franchisor's leadership style and franchisee's commitment in a franchise system. Results of the present study are expected to provide important theoretical and practical implications as to the role of franchisor's leadership style, as restricted by government regulations and the franchisee's self-efficacy, which could be needed to improve the quality of the long-term relationship between the franchisor and franchisee. Quoted by Northouse(2007), one problem regarding the investigation of leadership is that there are almost as many different definitions of leadership as there are people who have tried to define it. But despite the multitude of ways in which leadership has been conceptualized, the following components can be identified as central to the phenomenon: (a) leadership is a process, (b) leadership involves influence, (c) leadership occurs in a group context, and (d) leadership involves goal attainment. Based on these components, in this study leadership is defined as a process whereby franchisor's influences a group of franchisee' to achieve a common goal. Focusing on this definition, the path-goal theory is about how leaders motivate subordinates to accomplish designated goals. Drawing heavily from research on what motivates employees, path-goal theory first appeared in the leadership literature in the early 1970s in the works of Evans (1970), House (1971), House and Dessler (1974), and House and Mitchell (1974). The stated goal of this leadership theory is to enhance employee performance and employee satisfaction by focusing on employee motivation. In brief, path-goal theory is designed to explain how leaders can help subordinates along the path to their goals by selecting specific behaviors that are best suited to subordinates' needs and to the situation in which subordinates are working (Northouse, 2007). House & Mitchell(1974) predicted that although many different leadership behaviors could have been selected to be a part of path-goal theory, this approach has so far examined directive, supportive, participative, and achievement-oriented leadership behaviors. And they suggested that leaders may exhibit any or all of these four styles with various subordinates and in different situations. However, due to restrictive government regulations, franchisors are not in a position to change their leadership style to suit their circumstances. In addition, quoted by Northouse(2007), ssubordinate characteristics determine how a leader's behavior is interpreted by subordinates in a given work context. Many researchers have focused on subordinates' needs for affiliation, preferences for structure, desires for control, and self-perceived level of task ability. In this study, we have focused on the self-perceived level of task ability, namely, the franchisee's self-efficacy. According to Bandura (1977), self-efficacy is chiefly defined as the personal attitude of one's ability to accomplish concrete tasks. Therefore, it is not an indicator of one's actual abilities, but an opinion of the extent of how one can use that ability. Thus, the judgment of maintain franchisee's commitment depends on the situation (e.g., government regulation and policy and leadership style of franchisor) and how it affects one's ability to mobilize resources to deal with the task, so even if people possess the same ability, there may be differences in self-efficacy. Figure 1 illustrates the model investigated in this study. In this model, it was hypothesized that leadership styles would affect the franchisee's commitment, and self-efficacy would moderate the relationship between leadership style and franchisee's commitment. Theoretically, quoted by Northouse(2007), the path-goal approach suggests that leaders need to choose a leadership style that best fits the needs of subordinates and the work they are doing. According to House & Mitchell (1974), the theory predicts that a directive style of leadership is best in situations in which subordinates are dogmatic and authoritarian, the task demands are ambiguous, and the organizational rule and procedures are unclear. In these situations, franchisor's directive leadership complements the work by providing guidance and psychological structure for franchisees. For work that is structured, unsatisfying, or frustrating, path-goal theory suggests that leaders should use a supportive style. Franchisor's Supportive leadership offers a sense of human touch for franchisees engaged in mundane, mechanized activity. Franchisor's participative leadership is considered best when a task is ambiguous because participation gives greater clarity to how certain paths lead to certain goals; it helps subordinates learn what actions leads to what outcome. Furthermore, House & Mitchell(1974) predicts that achievement-oriented leadership is most effective in settings in which subordinates are required to perform ambiguous tasks. Marsh and O'Neill (1984) tested the idea that organizational members' anger and decline in performance is caused by deficiencies in their level of effort and found that self-efficacy promotes accomplishment, decreases stress and negative consequences like depression and emotional instability. Based on the extant empirical findings and theoretical reasoning, we posit positive and strong relationships between the franchisor's leadership styles and the franchisee's commitment. Furthermore, the level of franchisee's self-efficacy was thought to maintain their commitment. The questionnaires sent to participants consisted of the following measures; leadership style was assessed using a 20 item 7-point likert scale developed by Indvik (1985), self-efficacy was assessed using a 24 item 6-point likert scale developed by Bandura (1977), and commitment was assessed using a 6 item 5-point likert scale developed by Morgan & Hunt (1994). Questionnaires were distributed to Korean optical franchisees in Seoul. It took about 20 days to complete the data collection. A total number of 140 questionnaires were returned and complete data were available from 137 respondents. Results of multiple regression analyses testing the relationships between the each of the four styles of leadership shown by the franchisor as independent variables and franchisee's commitment as the dependent variable showed that the relationship between supportive leadership style and commitment ($\beta$=.13, p<.001),and the relationship between participative leadership style and commitment ($\beta$=.07, p<.001)were significant. However, when participants divided into high and low self-efficacy groups, results of multiple regression analyses showed that only the relationship between achievement-oriented leadership style and commitment ($\beta$=.14, p<.001) was significant in the high self-efficacy group. In the low self-efficacy group, the relationship between supportive leadership style and commitment ($\beta$=.17, p<.001),and the relationship between participative leadership style and commitment ($\beta$=.10, p<.001) were significant. The study focused on the franchisee's self-efficacy in order to explore the possibility that regulation, originally intended to protect the franchisee, may not be the most effective method to maintain the relationships in a franchise business. The key results of the data analysis regarding the moderating role of self-efficacy between leadership behavior style as proposed by path-goal and commitment theory were as follows. First, this study proposed that franchisor should apply the appropriate type of leadership behavior to strengthen the franchisees commitment because the results demonstrated that supportive and participative leadership styles by the franchisors have a positive influence on the franchisee's level of commitment. Second, it is desirable for franchisor to validate the franchisee's efforts, since the franchisee's characteristics such as self-efficacy had a substantial, positive effect on the franchisee's commitment as well as being a meaningful moderator between leadership and commitment. Third, the results as a whole imply that the government should provide institutional support, namely to put the franchisor in a position to clearly identify the characteristics of their franchisees and provide reasonable means to administer the franchisees to achieve the company's goal.