• Management & Information Systems Review
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• v.34 no.5
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• pp.23-47
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• 2015

In the Korea stock market, individual investors have perceived stock as short arbitrage investment, not long-term investment strategy. In order to reinforce stock market transparency and soundness, it is important to enforce the measures for stock market management. Especially, stock market event caused by financial policy can be given individual investors negative information regarding a stock trading. Thus, it is a need for investigating whether comprehensive review of listing eligibility is influenced on individual investors' responses and stock behaviors in respect of effectiveness. The purpose of this study to examine the relations between such stock market management and transitional aspect of individual investors' trading types and response on the based of pre- and post-event occurrence. Using an dataset of user's text messages on 9 firms posted on the firm-based social media (i.e., Naver, Daum, Paxnet) over the period 2009 to 2014. And we performed text-clustering and topic modeling according to keywords for classifying into investors group and non-investors groups and two types of investors were categorized depending on main topic transition by event windows in Comprehensive review of listing eligibility. The results indicated that a variety of stockholders existed in the stock. And the ratio of non-investors group was on the decrease, on the other hand, the proportion of investors group veer onto the side of pre-pattern after comprehensive review of listing eligibility. A distinctive feature of our study is to explain the influence of stock market management on response changes of individual investors as well as to categorize in accordance with time progression. Implications an suggestions for future research were also discussed.

• Tuberculosis and Respiratory Diseases
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• v.79 no.4
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• pp.257-266
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• 2016

Background: Idiopathic pulmonary fibrosis is a common interstitial lung disease; it is a chronic, progressive, and fatal lung disease of unknown etiology. Over the last two decades, knowledge about the underlying mechanisms of pulmonary fibrosis has improved markedly and facilitated the identification of potential targets for novel therapies. However, despite the large number of antifibrotic drugs being described in experimental pre-clinical studies, the translation of these findings into clinical practices has not been accomplished yet. NADH:quinone oxidoreductase 1 (NQO1) is a homodimeric enzyme that catalyzes the oxidation of NADH to $NAD^+$ by various quinones and thereby elevates the intracellular $NAD^+$ levels. In this study, we examined the effect of increase in cellular $NAD^+$ levels on bleomycin-induced lung fibrosis in mice. Methods: C57BL/6 mice were treated with intratracheal instillation of bleomycin. The mice were orally administered with ${\beta}$-lapachone from 3 days before exposure to bleomycin to 1-3 weeks after exposure to bleomycin. Bronchoalveolar lavage fluid (BALF) was collected for analyzing the infiltration of immune cells. In vitro, A549 cells were treated with transforming growth factor ${\beta}1$ (TGF-${\beta}1$) and ${\beta}$-lapachone to analyze the extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT). Results: ${\beta}$-Lapachone strongly attenuated bleomycin-induced lung inflammation and fibrosis, characterized by histological staining, infiltrated immune cells in BALF, inflammatory cytokines, fibrotic score, and TGF-${\beta}1$, ${\alpha}$-smooth muscle actin accumulation. In addition, ${\beta}$-lapachone showed a protective role in TGF-${\beta}1$-induced ECM expression and EMT in A549 cells. Conclusion: Our results suggest that ${\beta}$-lapachone can protect against bleomycin-induced lung inflammation and fibrosis in mice and TGF-${\beta}1$-induced EMT in vitro, by elevating the $NAD^+$/NADH ratio through NQO1 activation.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.2
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• pp.249-263
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• 2014

Established as the first science park in the world in the late 1950's, the Research Triangle Park(RTP) has not jut grown significantly but also has been successful in the transition from the exogenous development model to the endogenous development model. In this context, this paper attempts to explore the evolutionary path of the RTP by drawing upon the concept of triple-helix spaces of regional innovation. Firstly, the three research universities in the triangle area, as a knowledge space, played a fundamental role for forming the RTP. However, it is difficult to say that the regional universities, as opposed to the Silicon Valley and the Boston area, have had a significant impact on inducing the dynamics of the cluster evolution and the triple helix spaces. Secondly, it can be argued that the North Carolina's Board of Science and Technology, which was formed in 1961 but traced back to the 1950's in its origin, has been a centerpiece of a consensus space that makes a contribution to creating, sustaining and transforming the RTP as a triple-helix-based innovation cluster. Thirdly, there have been a plenty of agents to be an innovation space in the RTP. Particularly, the North Carolina Biotechnology Center(NCBC) and the Microelectronic Center of North Carolina(MCNC) have been the boundary permeable agents to make triple-helix agents interact. Today, the RTP has the triple-helix spaces with the structure that a consensus spaces is centered on out of the three, but all of those are inter-connected and influenced by each other. It can be claimed that the RTP today shows the dynamic structure of cluster evolution in a way in which the existing industry sectors have adapted to the changes in external environment and the new industry sectors have emerged at the same time.

• Journal of the Mineralogical Society of Korea
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• v.21 no.2
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• pp.209-224
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• 2008

Various types of high-purity limestone, which occurred in the Pungchon Formation, are examined to understand applied-mineralogical factors controlling their calcination characters with respect to the ore characters. To do this work, systematic characterization and determination were carried out for the limestone ores and their calcination products in a fixed heating condition, and the results were correlated and discussed. During the calcination experiment, a phase transition from calcite to quicklime begins to occur selectively in the physical weak zones such as grain boundary, cleavage and twin planes. All the fabrics of original limestones are preserved in the resultant quicklime. In addition, crystallinity of the quicklime was advanced, as the aging time of calcination was increased. Major controlling factors on the calcination effects of the high-purity limestone are elucidated to be the degree of development of cleavage and twin, together with crystallinity and textures in the limestone ore. Especially, lower crystallinity and dense interlocking fabrics obviously play advantageous role in all the calcination characters. But the development of cleavage and twin affects negatively on the calcination characters on account of favoring decrepitaion of quicklime in the lime manufacturing. Thus, the high-purity limestones characteristic of marble fabrics and relatively lower crystallinity are comparatively advantageous for the uses of lime manufacture.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.224-238
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• 1992

Hepatic fibrosis was induced in Sprague-Dawley rats to evaluate the ultrastructural changes of fat-storing cells(Ito cells). For experimental induction of liver fibrosis, the rats were administered intraperitoneally with 0.5ml of 50% $Ccl_4$ solution per Kg body weight, twice weekly for 12 weeks. The rats were sacrified every week. The liver tissues were examined under light and eletron microscopes. And the immunohistochemical study of desmin was also performed. The results were summarized as follows : Light microscopic findings : The cellular infiltrations with inflammatory cells and Kupffer cells developed from 1 week after $Ccl_4$ injection, and were the most severe in 4 weeks. The strong immunoreactivity for desmin was also evident in 4 weeks. The centrilobular necrosis and fibrosis developed from 2 weeks after injection, and the necrosis persisted until 8 weeks. The progress of fibrosis was accompanied by decreases in cellular infiltration and reactivity for desmin, and increased gradual nodular formation was also observed. The cirrhosis was developed after 10 weeks. Electron microscopic findings : An increase in number of fat-storing cells was observed from 1 week after injection. Transitional cells characterized by a depletion of lipid droplets and a hypertrophy of the rER appeared after 2 weeks. The number of transitional cells with abundant collagen fibers in the extracellular spaces increased in 4 weeks. With progression of fibrosis the number of fat-storing cells decreased and proliferating fibroblasts with dilated rER were observed. According to these results it was revealed that there was an apparent transition from fat-storing cells to transitional cells and to fibroblasts. These cells had a few similar characteristics and may belong to the same cell population. Thus it was suggested that fat-storing cells might play an important role in hepatic fibrosis.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.33-40
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• 2016

Objectives : Liver is one of the largest organs in the human, and has a function of detoxification and energy sensing to prevent severe disease. Paeoniae radix has been used to treat a variety of liver diseases such as hepatitis and chronic hepatic failure. Although P. radix has been used as an medicinal herb for a long time, the effects of P. radix on severe oxidative stress and its action mechanism on the liver was not clearly verified.Methods : This study investigated the protective effects of P. radix extract (PRE), and the underlying mechanism of its action in the liver. tert-butyl hydroperoxide (t-BHP) and carbon tetrachlroride (CCl₄) were used to induce oxidative stress in the HepG2 hepatocyte cell line and Sprague-Dawley rats, respectively.Results : t-BHP significantly induced cell death and ROS production in HepG2 cell, as indicated by MTT and FACS analysis. However, pretreatment of PRE inhibited a decrease in cell viability and H₂O₂ production in the HepG2 cells. PRE also blocked the ability of t-BHP to damage in mitochondrial membrane transition. More importantly, PRE induced Nrf2 activation and antioxidant Phase II enzyme, which may have a role in the effects of PRE. In mice, PRE inhibited the liver damage induced by CCl₄.Conclusions : PRE inhibited oxidative stress and hepatic damages as mediated with Nrf2 activation. This study unveil, in part, the effect and mechanism of old medicinal herb, P. radix.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.620-632
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• 2004

This paper tries to examine differences between geography classes taught by majored and non-majored teacher and to find problems in the latter case, tv observing four middle school geography classes in Seoul, from April to May 2003. The observation was fecund on (1) organization of a class (2) dialogue between teacher and students (3) strategy of explanation. In addition, the author conducted personal interviews with social studies teachers in the schools where the observations were made. The analyses of the observed classes were made by micro-ethnographic research method. Major findings of the observation and analysis are as follows. First, the transition from one topic to another topic was not smooth in the case of non-majored teacher class. Second, the questions that the non-majored teacher posed in the classroom played less significant role in keeping up the class in an organized fashion than those that the majored teacher posed. Third, the non-majored teacher focused on the concepts, terms and contents appeared in the textbook and simply tried to explain them, whereas the majored teacher demonstrated teaching methods such as comparing and contrasting cases to provide students with a more dynamic and comprehensive understanding on the topic they teamed. Fourth, the non-majored teacher used maps less frequently and less actively than the majored teacher. In addition, although the non-majored teachers are well aware of their problems in the class as a non-majored teacher, they think that the problems are inevitable in a given curriculum structure of social studies in Korea.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.24-34
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• 2015

As recent multilateral collaboration design system has been advanced, BIM based data exchange is a key factor for successful next generation building project. Even though many studies have been trying to set up a data compatibility system for collaboration, There are still a lot of problem in data exchange between design and engineering phase. Therefore, In this study, we analysis causes of problem for information exchange and suggest a IFC based Information exchange framework for improving BIM based design collaboration environment. In order to find out problems that hinder establishment of advanced open BIM information exchange, proper analysis about transition of process from current and to-be BIM based design collaboration process is important, at first. From analysis of main obstacles to information exchange, this research suggests solution plan using open API and IFC based BIM collaboration supporting system. The suggested open API solution named Integrity feedback system perform a role making up for weak point derived from IFC based data exchange. And main system suggestion about framework for IFC based information exchange reflect technological system support, requirement of function for collaboration including API/BCF plug-in.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.523-536
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• 2015

In this study, we analyzed the co-reflection of pre-service teacher community in three years of post-class discussions (PCD) on the basis of cultural historical activity theory in the case of an biological laboratory class program. We figured out the sociocultural elements of co-reflection of community using activity system suggested by $Engestr{\ddot{o}}m$. We also analyzed the aspect of reflection in terms of both 'the diversity of reflection subjects' and 'the practicality of reflection.' Finally, limitations of co-reflection were sought in a process of continuos circulation of reflection and practice. The results show that the sociocultural factors of 3-year-PCD changed, and in these changes, 'regular PCD,' 'introduction of tools for facilitating reflection,' 'transition of the subject in PCD from researcher to pre-service teachers' are remarkable. And in these process, co-reflection made positive progress since the content of reflection became diverse and practical. However, in some subjects such as 'managing time,' 'participation of students,' 'mentor's role (a kind of teaching manual),' reflective practice have not developed and similar patterns of discussion were repeated. From these results, we suggested ways of facilitating pre-service teacher community's co-reflection from the viewpoint of an activity system.

• Journal of Environmental Policy
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• v.6 no.1
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• pp.61-81
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• 2007

Types of agricultural policy can be catagorized into two general cases: price and income supports. Income supports are any government program designed to provide farmers with higher incomes than they would receive otherwise. These direct cash payments to farmers are known as "deficiency payment" or "direct payment" because they compensate the farmer for the failure of the market to provide farmers with adequate prices. The direct payment to environment-friendly agriculture is a form of income supports for the agriculture production using less pesticides and chemical fertilizers. Because no significant regulation exists on the use of fertilizers substituting chemical fertilizers for crop, the role of the payment on reducing environmental impacts of agriculture is not entirely clear. This uncertainty is likely to be particularly severe in the case that farmers with low-quality land showing greater demand for fertiliser have an incentive to transition to environment-friendly agriculture. The paper shows the case of the current payment system in Korea.