• Herbal Formula Science
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• v.32 no.2
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• pp.181-191
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• 2024

Objective : Inulae Flos(IF) has been used to treat arthritis, sever furuncle, fear and palpitation, vomiting, stroke, asthma and cough in Korean Medicine. Although the anticancer activity of IF has been reported, the molecular mechanism is still not well understood. In this study, we investigated the growth inhibitory activity of an ethanol extract of IF in HT-1080 human fibrosarcoma cells and its underlying mechanisms using two-dimensional (2D) and three-dimensional (3D) cell culture system. Methods : HT-1080 cells were cultured with IF for 9 days in 3D cell culture. To check an inhibition of cell prolifelation by IF, MTT assay was performed. DNA contents were measured using flow cytometry. Western blotting was used to evaluate the regulation of cell cycle- and autophagy-related proteins. Acridine orange staining was performed to confirm autophagy, and DCF-DA staining was performed to confirm the occurrence of ROS. Results : IF controlled a spheroid formation and decreased a cell viability in 3D cell culture. IF-induced cell proliferation inhibition was associated with a distinct increase of S and G2/M phase cell distribution in 2D cell cultre. In addition, IF significantly induced autophagy and generated reactive oxygen species(ROS). Interestingly, IF-induced cell cycle arrest and autophagy were recovered after pre-treatment of N-acetyl-L-cysteine, ROS scavenger. Conclusion : Our results indicate that IF induced ROS-mediated cell cycle arrest and autophagy and it may potentially useful for human fibrosarcoma treatment.

• Journal of Microbiology and Biotechnology
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• v.34 no.9
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• pp.1877-1889
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• 2024

Rhamnolipid (RL) is renowned for its efficacy in bioremediating several types of organic and metal contaminants. Nevertheless, there has been a scarcity of studies specifically examining the relationship between this substance and metals, especially in terms of their impact on RL formation and the underlying interaction processes. This study addresses this gap by investigating the RL mechanism in Cr (VI) remediation and evaluating its effect on RL production in Pseudomonas aeruginosa RW9. In this study, P. aeruginosa RW9 was grown in the presence of 10 mg l^-1 Cr (VI). We monitored RL yield, congeners distribution, and their ratios, as well as the transcriptional expression of the RL-encoded genes: rhlA, rhlB, and rhlC. Our results revealed that RL effectively reduced Cr (VI) to Cr (III), with RL yield increasing threefold, although with a slight delay in synthesis compared to control cells. Furthermore, Cr (VI) exposure induced the transcriptional expression of the targeted genes, leading to a significant increase in di-RL production. The findings confirm that Cr (VI) significantly impacts RL production, altering its structural compositions and enhancing the transcriptional expression of RL-encoded genes in P. aeruginosa RW9. This study represents a novel exploration of Cr (VI)'s influence on RL production, providing valuable insights into the biochemical pathways involved and supporting the potential of RL in Cr (VI) bioremediation.

• Childhood Kidney Diseases
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• v.12 no.1
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• pp.30-37
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• 2008

Purpose: The present study is an investigation of the progression and prognosis of acute intrinsic renal failure in neonates and children with a diagnosis of acute renal failure or other diseases on admission. Methods: This research is based on a retrospective analysis conducted on 59 patients(male: female=2.2:1) diagnosed with acute intrinsic renal failure between January 2000 and June 2006 at Busan Paik Hospital. The clinical diagnostic criteria of acute renal failure used was serum creatinine <1.2 mg/dL, oliguria with urine output$\leq$0.5 mL/kg/hr and anuria with urine output <50 mL per day. Results: Among those placed under investigation, 7 patients were neonates, 10 patients were 2 months-2 years old, 12 patients were 3-6 years old, 21 patients were 7-12 years old and 9 patients were 13-16 years old. It took 3.1${\pm}$2.8 days on average until the diagnosis was made. The urine output distribution was 21 persons for the oliguria group, and 36 persons for the non-oliguria group, and 2 persons for the anuria group. For the underlying causes, 30 persons were classified in the primary renal disease group, 14 persons in the infection group, 9 persons in the malignancy group, and 6 persons were categorized in another group. As for age distribution, the infected group was predominantly neonates, whereas the dominant age ranges for the primary renal disease and infection categories were 2 months to 2 years old. Also, the primary renal disease was dominant among older children, aged 3 and up. No difference was detected according to seasonal prevalence. However, there was a high morbidity rate among hemolytic uremic syndrome diagnosed in the summer. Peritoneal dialysis was used to treat 4 patients. It took 10.0${\pm}$6.7 days until the patients improved. 18 patients died. The non-oliguria group's mortality rate was lower than other groups. There was a high mortality rate in the neonates and malignancy group. Conclusion: Acute renal failure in childhood seems to take a better clinical course than in adulthood when there is an early diagnosis and proper treatment of underlying diseases.

• Management & Information Systems Review
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• v.30 no.2
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• pp.257-275
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• 2011

The price relationship between the futures market and the underlying spot market has attracted the attention of academics, practitioners, and regulators due to their roles during periods of turbulence in financial markets. The purpose of this paper is to investigate the dynamic of price relationship(or lead-lag relationship) between Korean Treasury Bond futures market and spot market. To examine the nature of the price relationship, descriptive statistics, serial correlation, and cross-correlation are used as a preliminary statistics in the Korean Treasury Bond spot and futures market. Next, following Stoll-Whaley(1990) and Chan(1992), the multiple regression method is used to examine the lead-lag patterns between the two markets. The empirical results are summarized as follows. The mean returns of spot markets and future markets are positive(+) and negative(-) respectively and the standard deviation of both stock and futures returns increase through the sub-periods. For the most periods, there is negative skewness in the both markets. The zero excess kurtosis due to the heavy tails of the distribution are relatively large. The autocorrelations in the spot returns for the sample periods are positive in time lag 1, but the autocorrelations in the future returns shows no significant evidence. The results of the daily cross-correlations between the KTB spot and futures returns indicate that a lead-lag relationship don't exist for price changes of futures and spot markets as a preliminary analysis. Finally, empirical results of regression analysis for both market indicate that there is no evidence that the KTB futures lead the KTB spot market, or the KTB spot market lead the KTB futures market. These results are robust for all sub-periods.

• Geophysics and Geophysical Exploration
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• v.16 no.3
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• pp.154-162
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• 2013

Vertical electrical sounding and 2D electrical resistivity survey were applied for evaluating the characteristics of alluvial layers at a groundwater artificial recharge site. The fine particles in alluvial layer, main target layer of groundwater artificial recharge, may cause clogging phenomena. In this case, electrical resistivity method is an effective technique to verify the spatial distribution of low-resistivity layers, such as saturated silts and clays. On the other hand, much attention should be paid to interpret the resistivity data in unconsolidated layers, because thick clayey overburden sometimes produces a masking effect on underlying interbedded resistive sands and gravels. Considering these points, we designed 35 points arranged in a grid form for vertical electrical sounding and 10 lines for 2D electrical resistivity survey, and concentrated our effort on enhancing the vertical and horizontal resolution of resistivity images. According to the results, 15 meters thick layers consisting of sands and gravels are located in 30 meters below ground. And the spatial distribution of silts and clays are mapped, which may cause clogging. Consequently, this approach can contribute to design and determine the location and depth of injection and observation wells for groundwater artificial recharge.

• Journal of Distribution Science
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• v.11 no.12
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• pp.39-49
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• 2013

Purpose - This study attempts to examine the underlying dimensions of service quality (tangibility, reliability, responsiveness, assurance, and empathy) for low-cost carriers. It subsequently seeks to determine the effect of the relationships of the dimensions of service quality, airline image, and behavioral intentions on airline services to provide adequate basic information and attributes for developing differentiated and competitive service marketing strategies. Research design, data, and methodology - The survey for this study was conducted on patrons with low-cost carrier boarding experiences in districts near universities and central businesses of Seoul and Busan from 5/10/2012 to 16/10/2012. Out of 346 questionnaires, 20 questionnaires with missing data and insincere answers were excluded for this study. Collected data were processed using SPSS 18.0, and the hypothesis was verified by analyzing the structural equation model with Lisrel 8.54. First, the frequency analysis was conducted to identify universal characteristics. Second, the exploratory factor analysis and reliability analysis were conducted to identify the accuracy of the variable measurements of the construct. Third, to assess uni-dimensionality and reliability, confirmatory factor analysis was conducted. Finally, to verify the adequacy of the research model and research hypothesis, the structural model was employed. Results - The results revealed that the factors, "tangibility, reliability, responsiveness, assurance, and empathy" were shown to be the most important dimensions of service quality for the airline image of the low-cost carrier which was consistent with previous studies. Therefore, it is fair to suggest that these verified factors are crucial attributes for the brand image of low-cost carriers. Second, as reliability and responsiveness were shown to be the most important factors for behavioral intentions, it is viable to suggest that these two attributes are crucial for the sales value of low-cost carriers. Further, it was found that the brand image of low-cost carriers was closely related to behavioral intentions. Therefore, in order to ensure the competitiveness and loyalty of patrons, the airline image value is a crucial attribute. Conclusions - The result of this study established that service quality is the most important attribute for marketing to ensure competitiveness, and intensive and differentiated service marketing play a crucial role in creating profits for low-cost carrier companies. First, as tangibility is found to be the most crucial factor in ensuring service quality, quality control and maintenance of medium and small carriers must be provided to ensure reliability, as they are the main attributes of low-cost carriers. Second, in order to promote positive behavioral intentions, it is essential to enhance the value of airline image. Third, in order to ensure competitiveness, it is imperative to carry out intensive and differentiated service marketing. Therefore, to promote the image of low-cost carriers and enhance behavioral intentions, the level of service quality must be secured by developing appropriate service improvement programs.

• The Journal of Industrial Distribution & Business
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• v.9 no.5
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• pp.63-72
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• 2018

Purpose - This work analyzes, in detail, the specification of vector error correction model (VECM) and thus examines the relationships and impact among seven economic variables for USA - balance on current account (BCA), index of stock (STOCK), gross domestic product (GDP), housing price indices (HOUSING), a measure of the money supply that includes total currency as well as large time deposits, institutional money market funds, short-term repurchase agreements and other larger liquid assets (M3), real rate of interest (IR_REAL) and household credits (LOAN). In particular, we search for the main explanatory variables that have an effect on stock and real estate market, respectively and investigate the causal and dynamic associations between them. Research design, data, and methodology - We perform the time series vector error correction model to infer the dynamic relationships among seven variables above. This work employs the conventional augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) unit root techniques to test for stationarity among seven variables under consideration, and Johansen cointegration test to specify the order or the number of cointegration relationship. Granger causality test is exploited to inspect for causal relationship and, at the same time, impulse response function and variance decomposition analysis are checked for both short-run and long-run association among the seven variables by EViews 9.0. The underlying model was analyzed by using 108 realizations from Q1 1990 to Q4 2016 for USA. Results - The results show that all the seven variables for USA have one unit root and they are cointegrated with at most five and three cointegrating equation for USA. The vector error correction model expresses a long-run relationship among variables. Both IR_REAL and M3 may influence real estate market, and GDP does stock market in USA. On the other hand, GDP, IR_REAL, M3, STOCK and LOAN may be considered as causal factors to affect real estate market. Conclusions - The findings indicate that both stock market and real estate market can be modelled as vector error correction specification for USA. In addition, we can detect causal relationships among variables and compare dynamic differences between countries in terms of stock market and real estate market.

• Journal of Distribution Science
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• v.12 no.9
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• pp.113-123
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• 2014

Purpose - After Korea's Free Economic Zone (FEZ) system was launched in 2003, there have been many debates about upgrading it and its support systems. However, as of 2013, there were insufficient results. Further, upon the designation of the East Coast and Chungbuk as official FEZs from February 4, 2013 by the 56th the Commission, there is a concern that many people are in the area designated as FEZ 8. This study investigates Korea's new FEZ system as part of Korea's primary new economic development policy in the 21st century. Therefore, this study examines views on the weaknesses of the past ten years of FEZs so that Korea can expand its FEZ system. Research design, data, and methodology -Many countries have considered the FEZ as an economic special zone. By reviewing previous research models, this study provides an update using recent data and materials, until 2013, from the Center of Free Economic Zones. In previous studies, the lack of support systems was attributed to proposals to ensure operational autonomy and differentiation of each FEZ; however, the main cause cannot be solved through regulatory issues, as difficulties caused by the operational system are responsible for the problems. We wish to analyze the FEZ, specifically the operational system; this is the main issue of this study. Results - After the first FEZs were established, it became necessary to have basic plans, as investment results in 2013 compared to the same period this year led to lower earnings in the first half of 2014. We propose an improvement of the operational system because in the free economic zones, the operational system is the root cause of the underlying problem. The results of this research are as follows. The weak management of the FEZ system is influenced by weak investment, delayed development, foreigners' living facilities, benefits of foreign investments, the control tower's policy making decision process, quickness of the process of satisfying legal requirements, and support For the independence of FEZs. Conclusion - Local governments do not have legal rights over FEZ deregulation and investment industries. This study suggests that the local government should have more independence from the central government. Moreover, independent management committees are more effective for ensuring public rights, better employee responsibilities, and better-qualified personnel. The FEZ committee struggles to effectively manage the locations of FEZs, foreign investments, and related facilities under the control of the Ministry of Trade, Industry and Energy. Thus, the FEZ committee should be under either the Prime Minister's office or the Presidential committee, to control and effectively coordinate between the local and central governments. If the problem clearly applies to the operational system in 2013, it is necessary to provide materials and methods so that the results of the first half of 2014 can be computed despite the data limits and lack of resources, and the data can be analyzed in a more diachronic thesis.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.242-253
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• 2017

We selected 81 universities (39.1%) for research and close analysis to analyze the current availability of courses in the field of clothing construction at four-year domestic universities. The results of the analysis shows that curriculum is currently composed of theoretical and practical courses that continue to be developed in diverse areas of study. Despite having classes with underlying similarities and differences, research shows that the course curriculum is constructed systematically with both theory and practice at each stage. Distribution of curriculum in the field of clothing construction were organized and analyzed by similar courses in 4 larger groupings and 9 sub-groups. Analysis of the large groupings showed that sewing courses (19.8%), pattern development courses (41.0%), advanced sewing courses (14.1%), and miscellaneous courses (26.1%) were established. Analysis of the sub-groups showed that basic theory and sewing courses (3.6%), sewing courses (16.1%), flat pattern courses (17.9%), draping pattern courses (14.6%), pattern CAD courses (7.3%), tailoring and advanced sewing courses (8.5%), scientific sewing and apparel production processing courses (1.4%), special sewing courses (3.9%), and miscellaneous and new subject courses (26.1%) were established. Overall analysis of the organization distribution was conducted in the order of pattern development (39.9%), miscellaneous & new subject (26.1%), basic theory and sewing (19.8%), and advanced sewing (14.0%). Field analysis from various angles indicates that pattern development, new subject courses, and miscellaneous courses had a relatively higher proportion than other major courses. From this it can be inferred that this trend is an effort to develop individuals to adapt to a rapidly changing fashion industry and environment. The composition of courses also shows great advancement towards diversification and course development. However, there is still insufficient exchange between industrial and education sites. As active exchange continue to be demanded, classification standards for new subject courses and titles of such studies have become unclear and have reached limitations.

• Journal of the Korea Society of Computer and Information
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• v.15 no.7
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• pp.57-66
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• 2010

Due to the advancement of IPTV technologies, open IPTV services are a step closer to becoming reality. In such service environment, users are able to enjoy IPTV services using a variety of devices available at their home domain. However, it is impossible to get such flexible services at their convenience unless each of devices is individually connected to Set-Top-Box (STB) because of Conditional Access System (CAS) or service providers otherwise allow STB to freely distribute decoded contents to every user devices attached to STB. In this paper, we propose a key management scheme for securely distributing contents from STB to multiple user devices at home domain. The proposed scheme also makes the service providers be able to control the access rights to each of user devices without installing individual STBs. It is achieved by computationally dividing a private key of RSA signature scheme into three parts and thus makes possible to distribute the contents scrambled through a underlying CAS mechanism without re-encrypting them that the existing scheme should employ. It improves significantly computation and communication complexities, maintaining it as secure as the existing schemes. Additionally, it prevents misbehaving users from illegally distributing the contents from STB to their devices available at home domain.