• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.20-20
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.97-97
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• Journal of Science Education
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• v.32 no.2
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• pp.121-145
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• 2008

The purposes of this study were to identify the misconceptions that students have on the magma and plate tectonics and to present the implications in developing textbooks as well as related curriculum of high school textbooks. Data were collected through questionnaire, consisting of some questions, short essays, and descriptive drawings, developed by the research team. A total of 140 high school students(9th graders) responded to those questionnaires and were interviewed for further information. It was reported that participants displayed various misconceptions related to magma and plate tectonics. The identified misconceptions are as follows: For the definition of magma, the 31% of participants misunderstood magma as lava. In respect to the generative mechanism of magma at subduction zone, over 90% of students responded that it is generated by frictional heat. The source of misconceptions were identified as a result from textbooks and related reference-books. For the concept of plates, 87% of students conceived 'crust or a lower part of the plates' as 'plates'. Most participants hold the right concept of oceanic ridge, whereas, 66% of them considered 'rift valley' as either 'divergence of continental plates' or 'converging boundary'. 63% of them defined 'collision boundary of continental plate' as either 'subduction zone' or 'diverging boundary'. For the definitions of the trench and Benioff zone, 86% of students responded them as the place of subduction or differing density between two converging plates. The students' misconceptions were resulted from the errors and insufficient explanation, inappropriate figures, and data presented in textbooks, reference-books, lecture, and web sites. The results of this study are implied to contribute the improvement of students' misconceptions.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.121-121
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• 2004

The groundwater in the Pocheon area occurs from both a fractured bedrock aquifer in igneous and metamorphic rocks and an alluvial aquifer with a thickness of <50 m, and forms a major source of domestic and agricultural water supply. In this study, we performed a hydrogeochemical study in order to identify the control of geochemical processes on groundwater quality. For this study, groundwater level and physicochemical parameters (EC, Eh, pH, alkalinity) were monitored once a month from a total of 150 groundwater wells between June 2003 to August 2004. A total of 153 water samples (13 surface water, 66 alluvial groundwater, 74 bedrock groundwater) were also collected and analyzed in February 2004. Groundwater chemistry in the study area is very complex, depending on a number of major factors such as geology, degree of chemical weathering, and quality of recharge water. Hydrochemical reactions such as the leaching of surficial and near-solace soil salts, dissolution of calcite, cation exchange, and weathering of silicate minerals are proposed to explain the chemistry of natural groundwater. Alluvial groundwaters locally have very high TDS concentrations, which are characterized by their chloride(nitrate)-sulfate-bicabonate facies and low Na/Cl ratio. Their grondwater levels are highly fluctuated according to rainfall event. We suggest that high nitrate content and salinity in such alluvial groundwaters originates from the local recharge of sewage effluents and/or fertilizers. Likewise, high concentrations of nitrate were also locally observed in some bedrock groundwaters, suggesting their effect of anthropogenic contamination. This is possibly due to the bypass flow taking place through macropores. Tile degree of the weathering of silicate minerals seems to be a major control of the distribution of major cations (sodium, calcium, magnesium, potassium) in bedrock groundwaters, which show a general increase with increasing depth of wells. Thermodynamic interpretation of groundwater chemistry shows that the groundwater in the study area is in chemical equilibrium with kaolinite and Na-montmorillonite, which indicates that weathering of plagioclase to those minerals is a major control of hydrochemistry of bedrock groundwater. The interpretation of the molar ratios among major ions, as well as the mass balance calculation, also indicates the role of both dissolution/precipitation of calcite and Ca-Na cationic exchange as bedrock groundwaters evolves progressively.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.173-185
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• 2003

This study mainly intends to determine the factors for which dental technicians are satisfied with their jobs and how much the resulting job transfer rate is and thus to identify the correlation between them. For these purpose, 200 subjects were sampled out of dental technicians in Seoul and Incheon, and the survey was performed from July 19, 2002 to August 15 (for 25 days) with self-administered questionnaire. Out of all collected questionnaires, 131 pieces(65.5%) were addressed for this study. As for the tools for this study, the structured questionnaire was used with its proven reliability and feasibility, and the contents of questionnaire consisted of 32 questions on the basis of related references. The contents of questionnaire were categorized into 3 sections: General attribute of subjects; Factors for which dental technicians are satisfied with their jobs; and their intention of job transfer. The questionnaire consisted of total 32 questions which included general attribute of subjects(10 questions), factors of their satisfaction with jobs(17 questions) and intention of job transfer(5 questions). The data analysis was processed by computerized system with SPSS(Statistical Package for Social Sciences). Statistical analysis techniques included frequency, percentage, T-test, F-test analysis and regression analysis. As a result of those analyses, the conclusion can be summarized as follows: 1. As a result of analyzing the factors for which the subjects were satisfied with their jobs, it was found that there were significant differences in career and job title out of question items(P<0.001). It was also shown that the factors of subjects' satisfaction averaged 3.43, which was considerably higher value than I expected. It was found that job and management factors were major job satisfaction factors. 2. As a result of analyzing the intention of subjects to decide their job transfer, it was found that there were significant differences in job title and marital status out of question items(P<0.001). It was shown that the total average of the intention of their job transfer amounted to 3.06. It was shown that dental technicians have relatively higher intention of job transfer from their current work place. 3. It was found that there was inverse correlation between the factors of subjects' satisfaction with their jobs and their intention of job transfer(r=-0.490, P<0.05). Likewise, it was also found that there was inverse correlation mostly between the evaluation value for each independent variable region in term of each factor of job satisfaction and the value for the intention of job transfer. In view of these correlations, it was concluded that higher job satisfaction likely led to lower job transfer. 4. As a result of regression analysis so as to determine the influences of job satisfaction factors on the intention of job transfer, it was found that the highest influential factor was management factor. And it was shown that the test values of model were statistically significant and its explanatory power amounted to 54.6%.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5349-5357
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• 2015

Background: Breast cancer is the most common cancer and the leading cause of cancer mortality among women of all ethnic and age groups in Malaysia. Delay in seeking help for breast cancer symptoms is preventable and by identifying possible factors for delayed diagnosis, patient prognosis and survival rates could be improved. Objectives: This narrative review aimed to understand and evaluate the level of in-depth breast cancer knowledge in terms of clinical breast examination and breast self-examination, and other important aspects such as side-effects and risk factors in Malaysian females. Since Malaysia is multicultural, this review assessed social perceptions, cultural beliefs and help-seeking behaviour in respect to breast cancer among different ethnic groups, since these may impinge on efforts to 'avoid' the disease. Materials and Methods: A comprehensive literature search of seven databases was performed from December 2015 to January 2015. Screening of relevant published journals was also undertaken to identify available information related to the knowledge, perception and help-seeking behaviour of Malaysian women in relation to breast cancer. Results: A total of 42 articles were appraised and included in this review. Generally, women in Malaysia had good awareness of breast cancer and its screening tools, particularly breast self-examination, but only superficial in-depth knowledge about the disease. Women in rural areas had lower levels of knowledge than those in urban areas. It was also shown that books, magazines, brochures and television were among the most common sources of breast cancer information. Delay in presentation was attributed mainly to a negative social perception of the disease, poverty, cultural and religion practices, and a strong influence of complementary and alternative medicine, rather than a lack of knowledge. Conclusions: This review highlighted the need for an intensive and in-depth breast cancer education campaigns using media and community health programmes, even with the existing good awareness of breast cancer. This is essential in order to avoid misconceptions and to frame the correct mind-set about breast cancer among women in Malaysia. Socio-cultural differences and religious practices should be taken into account by health care professionals when advising on breast cancer. Women need to be aware of the risk factors and symptoms of breast cancer so that early diagnosis can take place and the chances of survival improved.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.10 no.1
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• pp.117-127
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• 2015

Objectives : Most of pains are important symptoms caused by cancer transpered to spine. Harpagophyti Radix Pharmacopuncture is highly effective in reducing fever, pain, inflammation but was never used to reduce pain from cancer transpered to spine. So I intended to use Harpagophyti Radix Pharmacopuncture to control pain. The purpose of this study is to evaluate the clinical application of Harpagophyti Radix Pharmacopuncture for Bone Metastasis of Breast Cancer and Spinal Stenosis. Methods : We examined patient with Bone Metastasis of Breast Cancer and Spinal Stenosis who admitted Jaseng Korean Medicine Hospital. The patient was treated by Korean Medicine treatment and Harpagophyti Radix Pharmacopuncture. This case was assessed by Numerical Rating Scale(NRS), Oswestry Low Back Pain Disability Index(ODI), Short-Form 36 Health Survey(SF-36), ROM(Range of Movement) and Special Test. Results : In this study, the patient's pain was controlled and NRS, ODI were decreased. I could identify the improvement in life quality from the positive change of SF-36 and also found out that treatment was successful from the improvement of ROM, Special test. Conclusions : Harpagophyti Radix Pharmacopuncture with Korean Medicine treatment for Bone Metastasis of Breast Cancer and Spinal Stenosis was proved to be useful to the pain relief and function recovery, but further research should take place for clear understanding of the exact amount of dosage and safety. Moreover it must be accompanied by long term follow up research.

• Journal of Distribution Science
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• v.13 no.4
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• pp.45-53
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• 2015

Purpose - Online shopping enables consumers to conveniently purchase products irrespective of the time and place. As a result, several online shopping companies have emerged to cater to this growing market and, therefore, the competition among them has become increasingly intense. This paper evaluates the comparative efficiency of online shopping companies for a multi-year period (2009-2013), in order to help online shopping managers identify major drivers for enhancing management efficiency and the subsequent competitiveness. Research design, data, and methodology - The researchers collected the data from 2009 to 2013 from the distribution yearbook. This paper analyzes the marketability (sales figures), profitability (business profits), and management conditions (net profits) of domestic online shopping enterprises by incorporating information on human resources (number of employees) and material resources (total assets and capital). Therefore, the number of employees, total assets, and capital are selected as input variables, and sales figures, business profits, and net profits as the output variables. In this study, Data Envelopment Analysis (DEA) was used to measure the comparative efficiency of domestic online shopping companies. In addition, the Malmquist Productivity Index was used to evaluate the trend of change of Decision Making Units' (DMUs') efficiency for a multi-year period. Results - First, as of 2013, Interpark (2.415) was found to be the most efficient online shopping enterprise, followed by Aladdin Communications (2.117), Hyundai Home shopping (1.867), Home&Shopping (1.176), NS Home shopping (1.170), Commerce Planet (1.126), CJ O Shopping (1.105), Ebay Korea (1.088), and GS Home Shopping (1.051). Second, this study recognizes how the management efficiency has changed for the period 2009-2013. Third, the lesser the capital and employees, the more are the net profits, and the better is the management efficiency of domestic online shopping companies. Lastly, the productivity of such companies is influenced by endogenous factors rather than exogenous factors such as shifts in business environment and technological advances. Conclusions - DHC Korea influenced various distribution channels to reach customers through the Internet. Consequently, this helped in increasing the awareness about its products, in addition to an increase in sales. These achievements can be attributed to the characteristics of online shopping companies. Although it is easy for these companies to suggest goods for one-off purchases, they however have difficulties in retaining customers. Overcoming this challenge can be one of the ways to benchmark a successful case of an efficient company. For example, an online shopping company can attract customers by developing a corresponding mobile application as a convenient way to shop online. Additionally, they can satisfy customers by quick delivery of purchased products, which is possible by building an effective logistics network. Our study indicates that the productivity of an online shopping company was influenced by endogenous factors driven by improvements in managerial practices rather than exogenous factors. Accordingly, online shopping companies should adopt strategies to improve their operational efficiency rather than sales volume-oriented management.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.83-92
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• 2013

This study was to identify the differences on cognitions for conservation on the Rice Terraces landscape between local residents and visitors. For this purpose, this study drew problems and implications through consideration about advanced studies and then carried out a survey of local residents and visitors. The results of this study analyzed five factors that are the components of cognition about the Rice Terraces landscape: production, policy, landscape, management, and revitalization. The Cognition of Rice Terraces landscape indicated that local residents had more positive evaluation than visitors did. In addition, there were indicated differences in most items. Particularly, the local residents had more positive evaluation than visitors did in production(rice paddy of fallow ground, form of traditional rice paddy, weeds), landscape(cultural value, footpath of rice field and stonewall), and revitalization(common program for local residents and visitors, village revitalization from festival and event). Visitors had a more positive evaluation than local residents in terms of policy(designation of a place of scenic beauty, direct payment) and management(cooperation of local residents and visitors). In consideration of these results, it needs to draw up measures that are able to build up a common cognition to overcome differences between local residents and visitors. It is based on the knowledge and opinions that visitors and local residents had concerning history, traditions, cultures and production.

• Journal of Distribution Science
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• v.13 no.6
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• pp.105-118
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• 2015

Purpose - Currently, strengthening small and medium-sized enterprises (SME) in terms of competitiveness is a key economic issue. However, the problem is that many SMEs lack the internal competence required to cope with a rapidly changing market structure. Such problems can act as an obstacle to economic development, yet most SMEs in Korea are dealing with this problem today. A company's source of competitive advantage is changing from quantity to quality, facility to knowledge, and hardwork to creativity. Under such circumstances, a company should place learning and sharing of knowledge and continuously creating new knowledge as its priority. This study aims to identify the effect of a chief executive officer's (CEO) compassion and forgiveness - positive factors in organizational emotion - on learning organization activities and organizational performance, through a theoretical comparison. Research design, data, and methodology - For this study, SMEs based in Daejeon and Chungcheong area were selected. To secure credibility of the data, the subjects were selected among those who have been working at the business for six months or longer. The survey was conducted for 30 days from March 5, 2015 to April 5, 2015. Both offline and online surveys were conducted. Fifty companies were chosen and 700 questionnaires were distributed, with 506 used for analysis. Fifty subject companies (25 from Daejeon, 10 from Chungnam, 10 from Chungbuk, and five from Sejong) were selected and the objective, target, and survey content were explained to a manager at each company either face-to-face or on the phone. Of the total of 700 questionnaires distributed via mail or e-mail, 78.6% or 550 copies were returned. Excluding 44 insufficient questionnaires, the remainder, 506 questionnaires, were used for analysis. Results - This study analyzed how the CEO's compassion and forgiveness affects learning organization activities and organizational performance. First, compassion of the CEO at the SMEs directly affected the learning organization activities and indirectly affected the organizational performance. Second, forgiveness of the CEO at the SMEs did not affect the learning organization activities and organizational performance directly or indirectly. Conclusions - The study conclusions are as follows. First, CEO compassionate behavior at the SMEs was a significant variable that directly and indirectly affected learning organization activities and organizational performance. Therefore, the CEO of an SME can create a positive organizational atmosphere through compassionate behaviors in the organization. Second, the forgiving behavior of the CEO did not have direct or indirect effects on learning organization activities and organizational performance. However, the reason for a CEO to continue his or her forgiving behavior is because it strengthens employee resilience, commitment, and self-efficacy to protect the organization from negative influences such as layoffs, risks, and wrongdoings. The action of forgiveness does not have direct or indirect effects. However, the CEO shall continue such behavior to strengthen members' physiological resilience, commitment, and self - effectiveness, and to protect the organization from risks including layoff and external negative factors.