• Journal of Life Science
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• v.23 no.5
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• pp.710-720
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• 2013

Radiotherapy is commonly used in treating many kinds of cancers which cannot be cured by other therapeutic strategies. However, radiotherapy also induces the damages on the normal tissues. Radiation-induced fibrosis is frequently observed in the patients undergoing radiotherapy, and becomes a major obstacle in the treatment of intrahepatic cancer. Hedgehog (Hh) that is an essential in the liver formation during embryogenesis is not detected in the healthy liver, but activated and modulates the repair process in damaged livers in adult. The expression of Hh increases with the degree of liver damage, regulating the proliferation of hepatic progenitors and hepatic stellate cells (HSC). In addition, Hh induces epithelial-to-mesencymal transition (EMT) and activation of myofibroblasts. In the irradiated livers, up-regulated expression of Hh signaling was associated with proliferation of progenitors, EMT induction, and increased fibrosis. Female-specific expression of Hh leaded to the expansion of progenitors and the accumulation of collagen in the irradiated livers of female mice, indicating that gender disparity in Hh expression may be related with radiation-susceptibility in female. Hence, Hh signaling becomes a novel object of studies for fibrogenesis induced by radiation. However, the absence of the established experimental animal models showing the similar physiopathology with human liver diseases and fibrosis-favorable microenvironment hamper the studies for the radiation-induced fibrosis, providing a few descriptive results. Therefore, further research on the association of Hh with radiation-induced fibrosis can identify the cell and tissue-specific effects of Hh and provides the basic knowledge for underlying mechanisms, contributing to developing therapies for preventing the radiation-induced fibrosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1243-1252
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• 2017

There are limited programs for low sodium intake based on the nutrition education model for housewives who cook family meals. The objective of this study was to evaluate the effects of model-based nutrition programs for low sodium intake among housewives residing in Seoul by incorporating social cognitive theory. A questionnaire survey before and after education was conducted on 140 housewives who participated in the 'Low Sodium Nutritional Education Program' delivered by a district public health center for 12 weeks from November 2015 to January 2016. The contents of the nutrition education program and program evaluation items were based on the action plans for 'Less Sodium Healthy Practice' suggested by the Ministry of Food and Drug Safety. The results show that program participants showed a lower preference for sodium, higher selection of low sodium dishes from restaurants or cafeteria if available, and increased awareness of the need of restaurants to serve low sodium dishes compared to before. In terms of behavioral changes, there were significant improvements in checking nutrition labeling and selection of foods with low sodium, use of low sodium food products, use of natural seasonings to reduce salt intake, and consumption of fast foods and processed foods. On the other hand, requesting less salty meals when ordering and introducing restaurants or cafeterias with healthy and low sodium menus turned out to be difficult to put into practice. In conclusion, the nutrition education program for sodium intake reduction for housewives was effective in increasing knowledge, environment recognition, and behaviors related to low sodium intake but not behaviors related to physical environmental factors. Therefore, further nutrition education programs and practices for sodium intake reduction should be comprehensively implemented with improvement of physical environments for low sodium intake.

• Journal of Intelligence and Information Systems
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• v.21 no.1
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• pp.1-13
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• 2015

As opinion mining in big data applications has been highlighted, a lot of research on unstructured data has made. Lots of social media on the Internet generate unstructured or semi-structured data every second and they are often made by natural or human languages we use in daily life. Many words in human languages have multiple meanings or senses. In this result, it is very difficult for computers to extract useful information from these datasets. Traditional web search engines are usually based on keyword search, resulting in incorrect search results which are far from users' intentions. Even though a lot of progress in enhancing the performance of search engines has made over the last years in order to provide users with appropriate results, there is still so much to improve it. Word sense disambiguation can play a very important role in dealing with natural language processing and is considered as one of the most difficult problems in this area. Major approaches to word sense disambiguation can be classified as knowledge-base, supervised corpus-based, and unsupervised corpus-based approaches. This paper presents a method which automatically generates a corpus for word sense disambiguation by taking advantage of examples in existing dictionaries and avoids expensive sense tagging processes. It experiments the effectiveness of the method based on Naïve Bayes Model, which is one of supervised learning algorithms, by using Korean standard unabridged dictionary and Sejong Corpus. Korean standard unabridged dictionary has approximately 57,000 sentences. Sejong Corpus has about 790,000 sentences tagged with part-of-speech and senses all together. For the experiment of this study, Korean standard unabridged dictionary and Sejong Corpus were experimented as a combination and separate entities using cross validation. Only nouns, target subjects in word sense disambiguation, were selected. 93,522 word senses among 265,655 nouns and 56,914 sentences from related proverbs and examples were additionally combined in the corpus. Sejong Corpus was easily merged with Korean standard unabridged dictionary because Sejong Corpus was tagged based on sense indices defined by Korean standard unabridged dictionary. Sense vectors were formed after the merged corpus was created. Terms used in creating sense vectors were added in the named entity dictionary of Korean morphological analyzer. By using the extended named entity dictionary, term vectors were extracted from the input sentences and then term vectors for the sentences were created. Given the extracted term vector and the sense vector model made during the pre-processing stage, the sense-tagged terms were determined by the vector space model based word sense disambiguation. In addition, this study shows the effectiveness of merged corpus from examples in Korean standard unabridged dictionary and Sejong Corpus. The experiment shows the better results in precision and recall are found with the merged corpus. This study suggests it can practically enhance the performance of internet search engines and help us to understand more accurate meaning of a sentence in natural language processing pertinent to search engines, opinion mining, and text mining. Naïve Bayes classifier used in this study represents a supervised learning algorithm and uses Bayes theorem. Naïve Bayes classifier has an assumption that all senses are independent. Even though the assumption of Naïve Bayes classifier is not realistic and ignores the correlation between attributes, Naïve Bayes classifier is widely used because of its simplicity and in practice it is known to be very effective in many applications such as text classification and medical diagnosis. However, further research need to be carried out to consider all possible combinations and/or partial combinations of all senses in a sentence. Also, the effectiveness of word sense disambiguation may be improved if rhetorical structures or morphological dependencies between words are analyzed through syntactic analysis.

• Journal of Life Science
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• v.26 no.4
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• pp.419-430
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• 2016

Powdery mildew disease caused by Podosphaera xanthii is a major concern for Cucumis melo production worldwide. Knowledge on genetic behavior of the related genes and their modulating phytohormones often offer the most efficient approach to develop resistance against different diseases. Mildew Resistance Locus O (MLO) genes encode proteins with seven transmembrane domains that have significant function in plant resistance to powdery mildew fungus. We collected 14 MLO genes from ‘Melonomics’ database. Multiple sequence analysis of MLO proteins revealed the existence of both evolutionary conserved cysteine and proline residues. Moreover, natural genetic variation in conserved amino acids and their replacement by other amino acids are also observed. Real-time quantitative PCR expression analysis was conducted for the leaf samples of P. xanthii infected and phyto-hormones (methyl jasmonate and salicylic acid) treated plants in melon ‘SCNU1154’ line. Upon P. xanthii infection using 7 different races, the melon line showed variable disease reactions with respect to spread of infection symptoms and disease severity. Three out of 14 CmMLO genes were up-regulated and 7 were down-regulated in leaf samples in response to all races. The up- or down-regulation of the other 4 CmMLO genes was race-specific. The expression of 14 CmMLO genes under methyl jasmonate and salicylic acid application was also variable. Eleven CmMLO genes were up-regulated under salicylic acid treatment, and 7 were up-regulated under methyl jasmonate treatments in C. melo L. Taken together, these stress-responsive CmMLO genes might be useful resources for the development of powdery mildew disease resistant C. melo L.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.6
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• pp.499-510
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• 2006

Malignant tumors of the human salivary glands may arise from major or minor salivary glands. Adenoid cystic carcinoma (ACC) is the second most common malignant neoplasm in the salivary glands. ACC is occasionally highly aggressive tumor that readily invades adjacent tissues and metastasize to distant organs at early stages of the disease. Although ACC tends to grow slowly, treatment outcome may be poor due to wide local infiltration, perineural or intraneural spread and a propensity for hematogenous metastasis. Therefore, knowledge of cellular and molecular characteristics that influence the growth, survival and metastasis of tumor cells, is important for new treatment strategies of salivary ACC. I determined expressions of epiderma growth factor (EGF)-signaling molecules using surgical specimens of human ACCs. Protein expressions of EGF, transforming growth $factor(TGF)-{\alpha}$, EGF receptor (EGFR), phosphorylated EGFR (pEGFR), and human EGF receptor (HER)-2 were assessed in 18 cases of salivary ACC by immunohistochemical staining. Adjacent normal salivary tissues and mucosal tissues, uninvolved by the malignant tumor, served as internal controls. Most of the tumors, especially ACC with a tubulocribriform pattern, were positive for EGF signaling molecules. The overall percentages of the 18 specimens expressing EGF, $TGF-{\alpha}$, EGFR, pEGFR, and HER2 were 50, 89, 61, 61 and 83% respectively. Moreover, tumor-associated endothelial cells and infiltrating immune-related cells in the stroma of ACC, also expressed these biomarkers. Taken together, EGF-signaling molecules are actively expressed in salivary ACC. Therefore, we suggest that these biomarkers can be molecular targets for new treatment strategies of salivary tumors.

• Journal of radiological science and technology
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• v.37 no.3
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• pp.211-221
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• 2014

The clinical practices provide the students with a good opportunity to study the practical experiences in their field through the clinical training education in hospital. Now, in this study, comparing the perceptions of the clinic teachers with those of students at the clinical site. The study was conducted to the students attending universities located in Seoul and who finished the clinical practices in 2013. The questionnaires were distributed to the student and collected from them. The study were conducted to 275 questionnaires with frequency analysis, crosstabs, chi-square test and McNemar test. The major motivation was of the select radiography course was high employment rate(44.0%) and the satisfaction of radiography course was general(53.1%). 51.3% of the study answered 8 weeks current duration of clinical practices is proper. The 3-year course students answered that the period of clinical practices would be proper if it is performed in the winter vacation in their second year in college(47.3%). The 4-year course students answered that the first semester in their third years is proper for clinical practices( 27.7%). The students answered that they felt the lack in their knowledge on the professional field(32.4%) during the clinical practices and some of the practical training is different from the education performed at school(68.4%). Most of answered that they were satisfied with the clinical practices and among them they recognized the importance of the clinical practices ($3.94{\pm}0.89$). After the clinical practices, their desire for getting job as a radiography has changed from 84.1% to 82.9%. The reason why they want the job related to the radiation is because the job is stable (changed from 49.0% to 46.0% after the clinical practice) while the reason why they don't want be a radigrapher because that job is not proper for them (changed from 37.0% to 40.7% after the clinical practice) The effort should be made to enhance the position of radiation professionals through the improved education system to the students, rather giving them education for just employment.

• Journal of the Korean Geographical Society
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• v.42 no.3 s.120
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• pp.368-387
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• 2007

In order to explain geomorphological characteristics of the Korean Peninsula, it is necessary to understand the spatial distribution of tectonic movements and its causes. Even though geomorphological elements which might have been formed by tectonic movements(e.g. tilted overall landform, erosion surface, river terrace, marine terraces, etc.) have long been considered as main geomorphological research topics in Korea, the knowledge on the spatial distribution of tectonic movement is still limited. This research aims to identify the spatial distributions of tectonic movement via sequential analyses of Digital Elevation Model(DEM). This paper first developed a set of terrain analysis techniques derived from theoretical interrelationships between tectonic uplifts and landsurface denudation processes. The terrain analyses used in this research assume that elevations along major drainage basin divides might preserve original landsurfaces(psuedo-landsuface) that were formed by tectonic movement with relatively little influence by denudation processes. Psuedo-landsurfaces derived from a DEM show clear spatial distribution patterns with distinct directional alignments. Lines connecting psuedo-landsufaces in a certain direction are defined as psuedo-landsurface axes, which are again categorized into two groups: the first is uplift psuedo-landsurface axes that indicate the axis of landmass uplift; and the second is denudational psuedo-landsurface axes that cross step-shaped pusedo-landsurfaces formed via surface denudation. In total, 13 axes of pusedo-landsurface are identified in the Korean Peninsula, which show distinct direction, length, and relative uplift rate. Judging from the distribution of psudo-landsurfaces and their axes, it is concluded that the Korean Peninsula ran be divided into four tectonic regions, which are named as the Northern Tectonic Region, Center Tectonic Region, Southern Tectonic Region, and East Sea Tectonic Region, respectively. The Northern Tectonic Region had experienced a regional uplift centered at the Kaema plateau, and the rate of uplift gradually decreased toward southern, western and eastern directions. The Center Tectonic Region shows an arch-shaped uplift. Its uplift rate is the highest along the East Sea and the rate decreases towards the Yellow sea. The Southern Tectonic Region shows an asymmetric uplift centered a line connecting Dukyu and Jiri Mountains in the middle of the region. The eastern side of the Southern Regions shows higher uplift rate than that of the western side. The East Sea Tectonic Region includes south-eastern coastal area of the peninsula and Gilju-Myeongchun Jigudae, which shows relatively recent tectonic movements in Korea. Since this research visualizes the spatial heterogeneity of long-term tenonic movement in the Korean peninsula, this would provide valuable basic information on long-term and regional differences of geomorphological evolutionary processes and regional geomorphological differences of the Korean Peninsula.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.106-114
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• 2009

In maize, knowledge of genetic diversity and genetic relationships among elite inbred lines is an significant impact on the selection of parental lines for hybrid varieties. Genetic diversity and genetic relationships among 11 parental inbred lines of Korean waxy and normal corn varieties were analyzed using 50 SSR markers distributed over the whole genome. A total of 171 allele bands were detected with an average of 3.4 alleles per locus. Number of allele bands per locus ranged from two to six and gene diversity varied from 0.165 to 0.900 with an average of 0.596 depending on the SSR loci. The cluster tree recognized three major groups with 61.6% genetic similarity. Group I includes 7 inbred lines (KL103, HW1, HW4, HW6, HW7, HW8, HW9), with similarity coefficients of between 0.616 and 0.730. Group II includes 2 inbred lines (HF1, HF2), with similarity coefficients of 0.959. Group III includes 2 inbred lines (HW3, HW5), with similarity coefficients of 0.713. The present study indicates that the SSR markers chosen for this analysis are effective for the assessment of genetic diversity and genetic relationships among 11 parental inbred lines.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.187-195
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• 2019

The purpose of this study is to diagnose the operation status of high school integrated science newly introduced in the 2015 revised national curriculum and first applied in 2018, to examine teachers' perception on the new educational policy, and then based on this, extract implications for settling down the policy. A survey was administered to science teachers who participated in the in-service teacher training on integrated science, and the responses of 384 high school science teachers were analyzed. According to the results of the survey, integrated science was allotted six units to each school, and two or more teachers divided achievement standards and were responsible for them in many cases. Science teachers pointed to the increase of student-oriented activities as the biggest change due to the application of integrated science and also showed a positive attitude towards increasing the proportion of performance-based assessment, diversifying evaluation methods, increasing teacher consultations, and enhancing the holistic understanding of natural phenomenon, etc. In particular, teachers with 15 years or more of teaching experience were significantly positive about the increase of student-oriented activities, diverse assessment methods, and opportunities of teacher consultations. For teachers with a sub-major in science, teaching about non-majored contents was the most difficult and it was also difficult to determine the appropriate level of contents to teach. Teachers who majored common science, however, rarely complained about teaching non-majored content. In the case of two teachers in charge of integrated science, there was a statistically significant demand for subject matter knowledge as training content, and for mixed education incorporating theory and practice and customized training as a training method. In the case of one teacher responsible for the subject, there was a relatively lower demand. From these results, some implications for the successful implementation of integrated science were discussed.

• The Journal of Small Business Innovation
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• v.19 no.2
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• pp.53-68
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• 2016

Motivation and activities for technological learning, entrepreneurship, innovation, and creativity are driving forces of economic development in Asian countries. In the early stages of technological development, technological learning and entrepreneurship are efficient ways in which to catch up with advanced countries because firms can accumulate skills and knowledge quickly at relatively low risk. In the later stages of technological development, however, innovation and creativity become more important. This study aims to identify a) the factors (learning capabilities) that influence technological learning performance and b) barriers to enhancing innovation capabilities for the creative economy and organizations. The major part of this study is related to learning capabilities in the post-catch-up era. Based on a literature review and observations from Korean experiences, this study proposes a technological learning model composed of various influencing factors on technological learning. Three hypotheses are derived, and data are collected from Korean machine tool manufacturers. Intense interviews with CEOs and R&D directors are conducted using structured questionnaires. Statistical analysis, such as correlation and ANOVA are then carried out. Furthermore, this study addresses how to enhance innovation capabilities to move forward. Innovation enablers and barriers are identified by case studies and policy analysis. The results of the empirical study identify several levels of firms' learning capabilities and activities such as a) stock of technology, b) potential of technical labor, c) explicit technological efforts, d) readiness to learn, e) top management support, f) a formal technological learning system, g) high learning motivation, h) appropriate technology choice, and i) specific goal setting. These learning capabilities determine firms' learning performance, especially in the early stages of development. Furthermore, it is found that the critical factors for successful technological learning vary along the stages of technology development. Throughout the statistical and policy analyses, this study confirms that technological learning can be understood as an intrinsic principle of the technology development process. Firms perform proactive and creative learning in the late stages, while reactive and imitative learning prevails in the early stages. In addition, this study identifies the driving forces or facilitating factors enhancing innovation performance in the post catch-up era. The results of the preliminary case studies and policy analysis show some facilitating factors such as a) the strategic intent of the CEO and corporate culture, b) leadership and change agents, c) design principles and routines, d) ecosystem and collaboration with partners, and e) intensive R&D investment.