• Biomolecules & Therapeutics
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• v.21 no.5
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• pp.364-370
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• 2013

Resveratrol (trans-3,4'-trihydroxystillbene), a naturally occurring polyphenolic antioxidant found in grapes and red wine, elicits diverse biochemical responses and demonstrates anti-aging, anti-inflammatory, and anti-proliferative effects in several cell types. Previously, resveratrol was shown to regulate differentiation and inflammation in rabbit articular chondrocytes, while the direct production of nitric oxide (NO) in these cells by treatment with the NO donor sodium nitroprusside (SNP) led to apoptosis. In this study, the effect of resveratrol on NO-induced apoptosis in rabbit articular chondrocytes was investigated. Resveratrol dramatically reduced NO-induced apoptosis in chondrocytes, as determined by phase-contrast microscopy, the MTT assay, FACS analysis, and DAPI staining. Treatment with resveratrol inhibited the SNP-induced expression of p53 and p21 and reduced the expression of procaspase-3 in chondrocytes, as detected by western blot analysis. SNP-induced degradation of I-kappa B alpha ($I{\kappa}B-{\alpha}$) was rescued by resveratrol treatment, and the SN50 peptide-mediated inhibition of NF-kappa B (NF-${\kappa}B$) activity potently blocked SNP-induced caspase-3 activation and apoptosis. Our results suggest that resveratrol inhibits NO-induced apoptosis through the NF-${\kappa}B$ pathway in articular chondrocytes.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.7
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• pp.769-776
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• 2011

In order to cope with the requirements of smaller patterns, larger surfaces and lower costs in the fields of displays, optics and energy, greater attentions is now being paid to the development of micro-pattern machining technology. Compared with flat molds, roll molds have the advantages of short delivery, ease of manufacturing larger surfaces, and continuous molding. This paper presents the state-of-the-art of the micro pattern machining technology on the roll molds and introduces some research results on the machining process technology. The copper and nickel-phosphorous-alloy plating process, machining process technology for uniform micro patterns. micro cutting simulation and the real time monitoring system for micro machining are summarized. The developed technologies have led the complete localization of the prism sheets and will be applied to the direct forming process with succeeding research & development.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.5
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• pp.500-507
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• 2011

Acoustic emission(AE) signals during the polymerization shrinkage of composite resin subjected to the LED light exposure were detected through a wave guide method and a direct sensor attachment method. For PMMA, human tooth, stainless steel substrate, data of AE hits and amplitudes were compared. For the test using the wave guide, AE amplitudes decreased because of the attenuant wave. However, AE hits and 1st peak frequency distribution were not different according to the sensor attachments. Through the experiments, wave guide could be used for a nondestructive evaluation of the marginal disintegrative fracture of dental restoration.

• Nutritional Sciences
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• v.2 no.2
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• pp.65-70
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• 1999

Feeding rats a diet containing bean-hull causes hypertropy in their parotid glands due to the high tannin content. The amount of feedintake of rats led bean-hull was higher than that of rats fed a standard diet. However, the increase in body weight of rats fed bean-hull was lower than that of rats fed a standard diet, which resulted in significantly low feed efficiency of the bean-hull containing diet. Within one week, parotid glands significantly enlarged and a series of proline-rich proteins (PRPs) were produced, which were similar to those induced by feeding high-tannin sorghum with flight differences in molecular weights. Even though the direct comparison between PRPs produced by the bean-hull containing diet and those induced by the high sorghum diet is not appropriate due to laboratory inconsistences, several new PRPs were produced by high tannin diets in both experiments. Differences in molecular weights of PRPs induced in two different tannin sources must be funker investigated to be fully characterized. These morphological and biochemical changes have now been demonstrated to occur in response to the ingestion of tannins, presumably to diminish the anti-nutritional effects of tannins.

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.1042-1048
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• 1996

In order to investigate heating rate of commercial milk products in korean market, lactulose content and availability of calcium and ascorbic acid were measured. The pH range for raw and commercial milk was 6.5-6.75, and protein content was 2.5-3.13%. The acid degree value (。SH)showed between 5.3 and 7.1. There were no differences in pH, protein and acid degree among 3 types of milk. The portion ionic Ca content in UHT-milk(32.4%) and pasteurized milk (27%) increased significantly in comparison with raw milk (4.6%). Pasteurization led to loss of 20% ascorbic acid, and losses of UHT-treatment are approximately twice as high. Significant differences of lactulose content between UHT milk and pasteurized milk were observed. Some of UHT milk products showed very high value of lactulose content like sterilized milk. It is well known that the stress caused by indirect UHT treatment is slightly higher compared with the direct process. The results in this experiment suggested that most of UHT milk in korean market may be treated by indirect UHT method. In oder to keep the adventages of milk component, the heating methods of milk have to be reconsidered.

• The Journal of Information Systems
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• v.10 no.1
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• pp.73-95
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• 2001

A significant body of information systems research is concerned with user participation as a means to improve user satisfaction within systems development. In spite of the many studies in this area, findings are not consistent or cumulative. One of the reasons for this is not to be considered the type of systems. Most research are focusing on traditional system development under the mainframe environment instead of under end-user based environment like web-based information system or ERP. End-user based environment requires user's strong initiatives in the system development life cycle. It means the user\`s simple participation is not enough and user-led-development is more appropriate for the system success. This paper can call this new concept is end-user joint work which means user has to participate in the system development as a co-developer. This paper investigates how the end-user joint work contributes end-user satisfaction and two variables in particular-job complexity and technical competence-moderate the outcomes of end-user joint work Analysis of 112 independent systems development projects indicated that end-user joint work has a direct relationship with end-user satisfaction. In addition, the two variables were found to moderate key roles on this relationship. That is, the strength of this relationship depended on the level of these factors.

• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.265-270
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• 2002

Vocal cord dysfunction (VCD) is respiratory disorder characterized by paradoxical closure of the vocal cord during the respiratory cycle leading to obstructive airway symptoms. The clinical presentation of VCD is often dramatic and its misdiagnosis as asthma or exercise-induced brochospasm(EIB) has led to inappropriate treatment including high dose corticosteroids, intubation, and tracheostomy. Many VCD patients are asymptomatic at rest and require exercise challenge to elicit symptoms and vocal cord abnormalities. The "gold standard" for the diagnosis of VCD remains laryngoscopy or bronchoscopy with direct visualization of paradoxical adduction of the vocal cords. We report a case of exercise-induced Vocal cord masqueraded as exercise-induced asthma unresponsive to corticosteroids. And bronchodilator confirmed by typical bronchoscopic findings with paradoxial adduction of the vocal cords.

• Carbon letters
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• v.10 no.4
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• pp.314-319
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• 2009

The surface treatment effects of reinforcement filler were investigated based on the dynamic mechanical properties of mutiwalled carbon nanotubes (MWCNTs)/epoxy composites. The as-received MWCNTs(R-MWCNTs) were chemically modified by direct oxyfluorination method to improve the dispersibility and adhesiveness with epoxy resins in composite system. In order to investigate the induced functional groups on MWCNTs during oxyfluorination, X-ray photoelectron spectroscopy was used. The thermo-mechanical property of MWCNTs/epoxy composite was also measured based on effects of oxyfluorination treatment of MWCNTs. The storage modulus of MWCNTs/epoxy composite was enhanced about 1.27 times through oxyfluorination of MWCNTs fillers at $25^{\circ}C$. The storage modulus of oxyfluorinated MWCNTs (OF73-MWCNTs) reinforced epoxy composite was much higher than that of R-MWCNTs/epoxy composite. It revealed that oxygen content led to the efficient carbon-fluorine covalent bonding during oxyfluorination. These functional groups on surface modified MWCNTs induced by oxyfluorination strikingly made an important role for the reinforced epoxy composite.

• East Asian Economic Review
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• v.19 no.1
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• pp.71-97
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• 2015

This study examines the effects of several factors indicating economic openness-imported intermediate goods, total imports, IFDI (inward foreign direct investment), and foreign ownership-on regular, irregular jobs and the ratio of irregular employment to regular employment. Findings revealed that imported intermediate inputs and IFDI affected neither regular nor irregular job figures. However, an increase in total imports led to a decrease in the number of irregular jobs without affecting regular full time jobs, leading to a decrease in the ratio of irregular jobs to regular jobs. On the other hand, changes in foreign ownership structure had a contrary effect, that is, a decrease in the number of regular jobs and an increase in irregular ones, and, thus, an increase in the ratio of irregular jobs to regular jobs. Overall results showed that a rise in imports results in depressed overall employment, irregular employment in particular, while more IFDI results in more irregular jobs replacing regular ones, effectively exacerbating job insecurity. The implication of this analysis is that greater economic openness may have a negative impact on the South Korean labor market overall.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.27
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• pp.69-95
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• 2005

East Asia has played an important role in the economic and social development in the Asian pacific region and in the global arena. In the region the impact of companies centralizing their logistics activities around a few distribution centers has already led some leading ports such as Singapore, Hong Kong to transform and expand their functions and business activities to provide port users with value added logistics services. Other ports in the region also have an important part to play in the total logistics Chain. In these environments, the maritime activities of Jang BoGo, who was the maritime king of the commercial maritime empire in East Asia in the 9th century, give many implications to the international logistics network strategy that Korea has to take in order to become a power of International Logistics. Though the trading and economic environments at that time may be quite different from today, the super-national maritime management pattern that Jang Bo-go, founder of the Northeast Asian maritime trading kingdom devised, gives us many implications in the global trading and economic environments, in the respects of overseas direct investment and international logistics. Accordingly, the paper aims to examine the establishment of hub port in Northeast Asia, modelled after the maritime network management strategy of Jang BoGo.