• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.51-51
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• 2023

The world-wide rate of obesity is increasing continuously, representing a serious medical threat since it is associated with a variety of diseases including type 2 diabetes, cardiovascular disease, and numerous cancers. Sophora japonicais used as a traditional herb for medicinal purposes in eastern Asia. However, the anti-obesity effects of S. japonicafruit have not been explored. The aim of this study is to investigate the inhibition of adipocyte differentiation and adipogenesis by an ethanol extract of S. japonicafruit (EESF) in 3T3-L1 pre-adipocytes. Our results demonstrate that EESF suppressed the terminal differentiation of 3T3-L1 pre-adipocytes in a dose-dependent manner, as confirmed by a decrease in lipid droplet number and lipid content through Oil Red O staining. EESF significantly reduced the accumulation of cellular triglyceride, which was associated with a significant inhibition of the levels of pro-adipogenic transcription factors, including PPARγ, C/EBPα and C/EBPβ. In addition, EESF potentially down regulated the expression levels of adipocyte-specific proteins, including aP2 and leptin. In particular, EESF treatment effectively enhanced the activation of the AMPK signaling pathway; however, the co-treatment with compound C, an inhibitor of AMPK, significantly restored the EESF-induced inhibition of pro-adipogenic transcription factors and adipocyte-specific genes. These results indicate that EESF may exert an anti-obesity effect by controlling the AMPK signaling pathway, suggesting that the fruit extract of S. japonica may be a potential anti-obesity agent.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.1-8
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• 2023

Research, such as developing alternative energy in the transportation field, including aviation, is being actively conducted to solve the issue of current climate change. Interest in ammonia fuel as a carbon free energy (CFE) source is increasing due to the ease of liquefaction and transportation and similarity in energy density to that of methanol. However, explosiveness and toxicity of ammonia make it difficult to handle. Therefore, in this study, stable ammonia production was attempted using relatively easy-to-handle urea water solution (UWS). High temperature steam was used to promote the hydrolysis of ammonia. In order to determine the causes for ammonia production below the theoretical equivalent ratio, it was suggested that there were not enough collisions to promote the hydrolysis based on the kinetic theory of gases. The hydrolysis of unreacted isocyanic acid (HNCO) was tested according to the change in water supply. As a result, an increased amount of ammonia produced was confirmed. The increased amount of ammonia produced in a certain section was dependent on the steam temperature and the flow rate of water supplied.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.1
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• pp.1-10
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• 2024

Purpose: Lycopene is abundantly contained in Tomatoes and is known for diverse biological activities such as antioxidant, anti-inflammatory, and anticancer effects. In this study, the antioxidative potential of lycopene was investigated through the induction of hemeoxygenase (HO)-1 by nuclear factor-erythroid 2 p45-related factor2 (Nrf2) and upstream signaling molecules, mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Aktin RAW 264.7 cells. Methods: The antioxidative potential of lycopene against oxidative stress and its molecular mechanisms were determined by the cell viability assay, intracellular reactive oxygen species (ROS) formation assay, and Western blot analysis in RAW 264.7 cells. Results: Lycopene treatment significantly attenuated tert-butyl hydroperoxide (t-BHP) induced intracellular ROS formation in a dose-dependent manner without any cytotoxicity. In addition, 50 µM of lycopene for 6 h treatment induced potent HO-1 expression and its transcription factor, Nrf2. MAPK and PI3K/Aktwere also analyzed due to their critical roles in the regulation of cellular redox homeostasis against oxidative damage. As a result, phosphorylation of extracellular regulated kinase (ERK) was significantly induced by lycopene treatment while the activated status of c-Jun NH2-terminal kinase (JNK), p38, and Akt, were not given any effect. To confirm the antioxidative mechanism of HO-1 mediated by ERK activation, each selective inhibitor was employed in a protection assay, in which oxidative damage occurred by t-BHP. Lycopene, SnPP, and CoPP treatments reflected accelerated HO-1 expression could be a protective role against oxidative damage-initiated cell death. A selective inhibitor for ERK significantly inhibited the lycopene-induced cytoprotective effect but selective inhibitors for other signaling molecules did not attenuate the rate of t-BHP-induced cell death. Conclusion: In conclusion, lycopene potently scavenged intracellular ROS formation and enhanced the HO-1 mediated antioxidative potential through the modulation of Nrf2, MAPK signaling pathway in RAW 264.7 cells.

• Therapeutic Science for Rehabilitation
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• v.13 no.1
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• pp.87-97
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• 2024

Objective : This study aimed to acquire activities of daily living (ADL) skills through activity analysis and forward chaining in children with developmental disabilities. Methods : In this study, the performance of children with developmental disabilities was guided stepwise using a changing criterion design. The intervention was conducted in forward chaining after the therapist analyzed the activities of three tasks (shoes, shorts, and short-sleeved T-shirts) set as the Canadian Occupational Performance Measure (COPM). The performance rate at each stage of the three tasks was used as an independent variable, and COPM performance and satisfaction scores before and after the intervention were set as dependent variables. Results : The task performance rates of children wearing shoes, shorts, and short-sleeved T-shirts improved over time. Even at home, the scores for performance and satisfaction of all three tasks increased. Conclusion : Hopefully, activity analysis and behavioral chaining methods will be used not only for ADL but also for various tasks in children with developmental disabilities who have difficulty acquiring tasks.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1454-1463
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• 2023

Evaluating the antioxidant efficacy using Potentillae Chinensis Herba extract, the anti-inflammatory efficacy was tested in respiratory mucosal epithelium, RAW264.7 cells, and zebrafish. As a result, antioxidant activity increased in a concentration-dependent manner in DPPH free radical scavenging and ABTS+ cation radical activities. As a result of MTT assay for cell experiments, the survival rate of NCI-H292 cells was reduced to less than 70% when treated at each concentration of 100 ㎍/ml, subsequent experiments were conducted at 50 ㎍/ml. Anti-inflammatory efficacy evaluation, NO production, TNF-𝛼, IL-1𝛽, and PGE₂ decreased, and COX-2 also decreased significantly at 50 ㎍/ml. The mucin protein expression of Potentillae Chinensis Herba extract and bioconverted extract, it was observed that MUC5AC expression was significantly reduced. In the zebrafish toxicity evaluation, concentrations below 50 ㎍/ml did not show embryotoxicity and showed anti-inflammatory efficacy by reducing NO production due to LPS. The above results are valid to be valuable for use as a functional material that suppresses inflammation by helping the expression of Potentillae Chinensis Herba's respiratory mucus proteins.

• Journal of Venture Innovation
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• v.7 no.1
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• pp.59-75
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• 2024

As the 4th Industrial Revolution progresses, the importance of startups was increasingly emphasized. Nevertheless, the five-year survival rate of Korean startups was lower than that of OECD countries. In this study, we analyzed the relationship between agile leadership, learning agility, and organizational performance of startups under the premise that organizational performance was most important for startups to achieve sustainable growth. For the empirical analysis, agile leadership was set as an independent variable, learning agility was set as a mediating variable, and organizational performance was set as a dependent variable. Data was collected from startup employees across the country, and 197 valid samples were selected for analysis. The empirical analysis used Process Macro 4.2. As a result of the empirical analysis, agile leadership was found to have a significant positive effect on startup organizational performance. Additionally, agile leadership had a positive (+) effect on learning agility, and learning agility had a positive (+) effect on startup organizational performance. As a result of analyzing the mediating effect of learning agility, learning agility was found to play a mediating role between agile leadership and organizational performance. Academically, these research results tested the usefulness of agile leadership suited to the startup culture among various leadership styles that can improve the organizational performance of startups. In practical terms, such agile leadership not only directly affects organizational performance, but also through the learning agility of startup employees. This means that by creating a culture of learning agility that encourages startup employees to continuously learn and adapt, startups can increase their chances of survival and success.

• Journal of Surface Science and Engineering
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• v.57 no.5
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• pp.425-431
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• 2024

As demand in the electric vehicle market increases, the development of high capacity, high energy density lithium-ion batteries (LIBs) is required. Silicon has a extremely high theoretical capacity of 4200 mAh/g, but low cycle life and structural instability due to high volume expansion during charging and discharging are critical issue to solve. A reduced silicon oxide has also a high theoretical capacity of 2500 mAh/g and recently studied extensively for its low-cost, superior cycle life, and structural stability. In this study, we first synstheized SiO₂ particles by sol-gel method using tetraethyl orthosilicate (TEOS) precursor. The SiO₂ particle size was controlled with an average particle size of 300-600 nm by the addition amount of TEOS, NH₃, and H₂O. The synthesized SiO₂ particles were reduced to SiO_x through the magnesiothermic reduction reaction (MRR), and electrochemical characteristics were evaluated according to the particle size of SiO_x. For electrochemical characterization, SiO_x (10 wt.%) was mixed with graphite, and 2032 half cells were fabricated to obtain charge-discharge curve, cycle performance, rate performance, and electrochemical impedance spectroscopy curves. As a result, the mean size of SiO_x particle decreases from 600 to 300 nm, the initial discharge capacity increases from 459.9 to 556.5 mAh/g with the single capacity from 1359.4 to 2325.3 mAh/g, respectively. Finally, the present result shows the availability of MRR process to obtain reduced silicon oxide particles and sized dependent electrochemical properties to develop high capacity and high energy density LIBs.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.1-34
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• 1974

These experiments pertain to various factors influencing the quantitative characters of cocoon crops in summer and early autumn seasons. Initially, in order to establish the possible ways of the silkworm rearing more than three times a year in Korea, the author attempted to get further information about the various factors affecting the cocoon crop in every silkworm rearing season. The trials were conducted eleven times a year at four places for three years. The field trial was conducted with 19 typical sericultural farmers who had been surveyed. At the same time the author statistically analyzed the various factors in close relation to tile cocoon crop in autumn season. The effect of guidance on 40 sericultural farmers was analyzed, comparing higher level farmers with lower level farmers ; and the author surveyed 758 non-guided farmers near the guided farmers during both spring and autumn seasons. In addition, another trial on the seasonal change of leaf quality was attempted with artificial diets prepared with leaves grown in each season. It was found that related factors to cocoon crops in summer and early autumn seasons appeared to be leaf quality, and temperature for young and grown larvae. A 2$^4$ factorial experiment was designed in summer season, and another design with one more level of varied temperature or hard leaf added to a 24 factorial experiment was conducted in early autumn. The experimental results can be summarized： 1. Study on the cocoon crops in the different rearing seasons 1) It was shown that earlier brushing of silkworm generally produced the most abundant cocoon crop in spring season, and earlier or later than the conventional brushing season, especially earlier brushing was unfavorable for the abundant cocoon crop in autumn season. 2) The cocoon crop was affected by the rearing season, and decreases in order of sire with spring, autumn, late autumn, summer and early autumn seasons. 3) It was Proved that ordinary rearing and branch rearing were possibles 4 times a year ; in the 1st, 3rd, 8th, and 10th brushing season. But the 11th brushing season was more favorable for the most abundant cocoon crop of branch rearing, instead of the 10th brushing season with ordinary rearing. 2. Study on the main factors affecting the cocoon crop in autumn season 1) Accumulated pathogens were a lethal factor leading to a bad cocoon crop through neglect of disinfection of rearing room and instruments. 2) Additional factors leading to a poor cocoon crop were unfavorable for rearing temperature and humidity, dense population, poor choice of moderately ripened leaf, and poor feeding techniques. However, it seemed that there was no relationship between the cocoon crop and management of farm. 3) The percentage of cocoon shell seemed to be mostly affected by leaf quality, and secondarily affected by the accumulation of pathogens. 3. Study on the effect of guidance on rearing techniques 1) The guided farms produced an average yearly yield of 29.0kg of cocoons, which varied from 32.3kg to 25.817g of cocoon yield per box in spring versus autumn, respectively. Those figures indicated an annual average increase of 26% of cocoon yield over yields of non-guided farmers. An increase of 20% of cocoon yield in spring and 35% of cocoon yield in autumn were responsible. 2) On guided farms 77.1 and 83.7% of total cocoon yields in the spring and autumn seasons, respectively, exceeded 3rd grade. This amounted to increases of 14.1 and 11.3% in cocoon yield and quality over those of non-guided farms. 3) The average annual cocoon yield on guided farms was 28.9kg per box, based on a range of 31.2kg to 26.9kg per box in spring and autumn seasons, respectively. This represented an 8% increase in cocoon yield on farms one year after guidance, as opposed to non-guided farms. This yield increase was due to 3 and 16% cocoon yield increases in spring and autumn crops. 4) Guidance had no effect on higher level farms, but was responsible for 19% of the increases in production on lower level farms. 4. Study on the seasonal change of leaf quality 1) In tests with grown larvae, leaves of tile spring crop incorporated in artificial diets produced the best cocoon crop; followed by leaves of the late autumn, summer, autumn, and early autumn crops. 2) The cocoon crop for young larvae as well as for grown larvae varied with the season of leaf used. 5. Study on factors affecting the cocoon crops in summer and early autumn A. Early autumn season 1) Survival rate and cocoon yield were significantly decreased at high rearing temperatures for young larvae 2) Survival rate, cocoon yield, and cocoon quality were adversely affected by high rearing temperatures for grown larvae. Therefore increases of cocoon quantity and improvement of cocoon quality are dependent on maintaining optimum temperatures. 3) Decreases in individual cocoon weight and longer larval periods resulted with feeding of soft leaf and hard leaf to young larvae, but the survival rate, cocoon yield and weight of cocoon shell were not influenced. 4) Cocoon yield and cocoon quality were influenced by feeding of hard leaf to grown larvae, but survival rate was not influenced by the feeding of soft leaf and hard leaf. 5) When grown larvae were inevitably raised at varied temperatures, application of varied temperature in the raising of both young and grown larvae was desirable. Further research concerning this matter must be considered. B. Summer season 1) Cocoon yield and single cocoon weight were decreased at high temperatures for young larvae and survival rate was also affected. 2) Cocoon yield, survival rate. and cocoon quality were considerably decreased at high rearing temperatures for grown larval stages.

• Korean small business review
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• v.31 no.2
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• pp.85-102
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• 2009

With the continued globalization of world markets, transfer pricing has become one of the dominant sources of controversy in international taxation. Transfer pricing is the process by which a multinational corporation calculates a price for goods and services that are transferred to affiliated entities. Consider a Korean electronic enterprise that buys supplies from its own subsidiary located in China. How much the Korean parent company pays its subsidiary will determine how much profit the Chinese unit reports in local taxes. If the parent company pays above normal market prices, it may appear to have a poor profit, even if the group as a whole shows a respectable profit margin. In this way, transfer prices impact the taxable income reported in each country in which the multinational enterprise operates. It's importance lies in that around 60% of international trade involves transactions between two related parts of multinationals, according to the OECD. Multinational enterprises (hereafter MEs) exert much effort into utilizing organizational advantages to make global investments. MEs wish to minimize their tax burden. So MEs spend a fortune on economists and accountants to justify transfer prices that suit their tax needs. On the contrary, local governments are not prepared to cope with MEs' powerful financial instruments. Tax authorities in each country wish to ensure that the tax base of any ME is divided fairly. Thus, both tax authorities and MEs have a vested interest in the way in which a transfer price is determined, and this is why MEs' international transfer prices are at the center of disputes concerned with taxation. Transfer pricing issues and practices are sometimes difficult to control for regulators because the tax administration does not have enough staffs with the knowledge and resources necessary to understand them. The authors examine transfer pricing practices to provide relevant resources useful in designing tax incentives and regulation schemes for policy makers. This study focuses on identifying the relevant business and environmental factors that could influence the international transfer pricing of MEs. In this perspective, we empirically investigate how the management perception of related variables influences their choice of international transfer pricing methods. We believe that this research is particularly useful in the design of tax policy. Because it can concentrate on a few selected factors in consideration of the limited budget of the tax administration with assistance of this research. Data is composed of questionnaire responses from foreign firms in Korea with investment balances exceeding one million dollars in the end of 2004. We mailed questionnaires to 861 managers in charge of the accounting departments of each company, resulting in 121 valid responses. Seventy six percent of the sample firms are classified as small and medium sized enterprises with assets below 100 billion Korean won. Reviewing transfer pricing methods, cost-based transfer pricing is most popular showing that 60 firms have adopted it. The market-based method is used by 31 firms, and 13 firms have reported the resale-pricing method. Regarding the nationalities of foreign investors, the Japanese and the Americans constitute most of the sample. Logistic regressions have been performed for statistical analysis. The dependent variable is binary in that whether the method of international transfer pricing is a market-based method or a cost-based method. This type of binary classification is founded on the belief that the market-based method is evaluated as the relatively objective way of pricing compared with the cost-based methods. Cost-based pricing is assumed to give mangers flexibility in transfer pricing decisions. Therefore, local regulatory agencies are thought to prefer market-based pricing over cost-based pricing. Independent variables are composed of eight factors such as corporate tax rate, tariffs, relations with local tax authorities, tax audit, equity ratios of local investors, volume of internal trade, sales volume, and product life cycle. The first four variables are included in the model because taxation lies in the center of transfer pricing disputes. So identifying the impact of these variables in Korean business environments is much needed. Equity ratio is included to represent the interest of local partners. Volume of internal trade was sometimes employed in previous research to check the pricing behavior of managers, so we have followed these footsteps in this paper. Product life cycle is used as a surrogate of competition in local markets. Control variables are firm size and nationality of foreign investors. Firm size is controlled using dummy variables in that whether or not the specific firm is small and medium sized. This is because some researchers report that big firms show different behaviors compared with small and medium sized firms in transfer pricing. The other control variable is also expressed in dummy variable showing if the entrepreneur is the American or not. That's because some prior studies conclude that the American management style is different in that they limit branch manger's freedom of decision. Reviewing the statistical results, we have found that managers prefer the cost-based method over the market-based method as the importance of corporate taxes and tariffs increase. This result means that managers need flexibility to lessen the tax burden when they feel taxes are important. They also prefer the cost-based method as the product life cycle matures, which means that they support subsidiaries in local market competition using cost-based transfer pricing. On the contrary, as the relationship with local tax authorities becomes more important, managers prefer the market-based method. That is because market-based pricing is a better way to maintain good relations with the tax officials. Other variables like tax audit, volume of internal transactions, sales volume, and local equity ratio have shown only insignificant influence. Additionally, we have replaced two tax variables(corporate taxes and tariffs) with the data showing top marginal tax rate and mean tariff rates of each country, and have performed another regression to find if we could get different results compared with the former one. As a consequence, we have found something different on the part of mean tariffs, that shows only an insignificant influence on the dependent variable. We guess that each company in the sample pays tariffs with a specific rate applied only for one's own company, which could be located far from mean tariff rates. Therefore we have concluded we need a more detailed data that shows the tariffs of each company if we want to check the role of this variable. Considering that the present paper has heavily relied on questionnaires, an effort to build a reliable data base is needed for enhancing the research reliability.

• Journal of agricultural medicine and community health
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• v.30 no.2
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• pp.167-182
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• 2005

Objectives: This study was performed to investigate the prevalence of knee osteoarthritis according to the criteria of diagnosing knee osteoarthritis in rural women and the factors related with this disease. Methods: The data obtained from 200 women older than 40 years of age residing in 5 Ri's in Goryeong-gun. Gyeongsanbuk-do by random cluster sampling from September to October 2002. Knee osteoarthritis was determined positive according to the Kellgren and Lawrence classification and knee pain. Results: Among these subjects, 71.0% showed more than grade 2 in radiologic finding and the rate of knee pain according to the survey was 67.0%. The rate of subjects meeting the criteria of knee osteoarthritis was 54.0%. According to univariate analysis, the prevalence of knee osteoarthritis increased with age and those farming people and people working in household industry was significantly high at 58.9% compared with others. The prevalence of knee osteoarthritis showed a significant relationship with the family history and past history of knee injury and knee surgery(p<0.01), and diabetes mellitus(p<0.05). The score of ADL was significantly different in the subjects with knee osteoarthritis compared with normal group(p<0.05). When the presence of knee osteoarthritis and the period of the life style of seating down on the floor were compared, a significant difference was present between the osteoarthritis group and normal group. As for metabolic factors, the blood sugar level, bone density, and body mass index(BMI) were significantly different in the osteoarthritis group compared with normal group. When multiple logistic regression analysis was performed with the presence of knee osteoarthritis as the dependent variable, the prevalence of knee osteoarthritis was significantly affected by older age, subjects farming or working in household industry, the history of knee injury, the history of surgery, higher blood sugar level, and higher BMI. Conclusions: These subjects need an intervention through self-care programs such as exercise for preventing osteoarthritis, weight control programs, other exercise programs strengthening knee joints, and guidelines when working in vinyl houses.