• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7553-7558
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• 2014

The Piwi subfamily comprises two argonaute (Ago) family proteins, which are defined by the presence of PAZ and Piwi domains, with well known roles in RNA silencing. Hiwi, a human Piwi subfamily member, has been shown to play essential roles in stem cell self-renewal and gametogenesis. Recently, accumulating reports have indicated that abnormal hiwi expression is associated with poorer prognosis of multiple types of human cancers, including examples in the breast. However, little is known about details of the oncogenic role of hiwi in breast cancers. In present study, we confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines at both mRNA and protein levels. Thus both RT-qPCR and Western blot data revealed significantly higher hiwi in intratumor than peritumor specimens, overexpression being associated with tumor size, lymph node metastasis and histological grade. Hiwi overexpression was also identified in breast cancer cell lines, MDA-MB-231 and MCF-7, and gain-of-function and loss-of-function strategies were adopted to identify the role of hiwi in the MCF-7 cell growth. Results demonstrated that hiwi expression in MCF-7 cells was significantly up- or down-regulated by the two strategies. We next evaluated the influence of hiwi overexpression or knockdown on the growth of breast cancer cells. Both cell count and colony formation assays confirmed promoting roles of hiwi in MCF-7 cells, which could be inhibited by hiwi specific blockage by siRNAs. In summary, the present study confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines, and provided e vidence of promotion by hiwi of cell growth. The results imply an oncogenic role of hiwi in breast cancers.

• The Journal of Korean Association of Computer Education
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• v.11 no.5
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• pp.33-45
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• 2008

Field study improves students' capacity for studying and thinking about their surrounding environments. It also develops further interest academic study by allowing them to learn curriculum related materials from actual experience. Moreover, students acquire the capacity for independent and self regulated learning in the course of making efforts to solve problems they face in the environment. Our efforts arc directed at designing and developing a RFID based support system-based on the constructionist's learning theory to help students perform field study more efficiently. The field study support system can be implemented not only in museums but also in botanical gardens, zoos, art galleries, and science centers. Based on the results of the verification at the sample museum we will expand the target locations to implement the field trip support system. We expect that our field study support system will be a catalyst for improving learning in the fields.

• Fashion & Textile Research Journal
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• v.18 no.6
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• pp.766-775
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• 2016

In the era of globalization and unlimited competition, Korean universities need a breakthrough in their education system according to the changing education landscape, such as lower graduation requirements to cultivate more multi-talented convergence leaders. While each student has different learning capabilities, which results in different performance and achievements in the same class, the uniform education that most universities are currently offering fails to accommodate such differences. Blended learning, synergically combining offline and online classes, enlarges learning space and enriches learning experiences through diversified tools and materials, including multimedia. Recently, universities are increasingly adopting video contents and on-offline convergence learning strategy. Thus, this study suggests a teaching method based on blended learning to more effectively teach existing pattern CAD and virtual CAD in the Apparel Pattern CAD class. To this end, this researcher developed a teaching-learning method and curriculum according to the blended learning phase and video-based contents. The curriculum consisted of 2D CAD (SuperAlpha: Plus) and 3D CAD (CLO) software learning for 15 weeks. Then, it was loaded to the Learning Management System (LMS) and operated for 15 weeks both online and offline. The performance analysis of LMS usage found that class materials, among online postings, were viewed the most. The discussion menu most accurately depicted students' participation, and students who did not participate in discussions were estimated to check postings less than participating students. A survey on the blended learning found that students prefer digital or more digitized classes, while preferring face to face for Q&As.

• Journal of Engineering Education Research
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• v.14 no.4
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• pp.11-19
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• 2011

The purpose of this study was to identify learning strategies by learning style of first-year engineering students in order to find implications for teaching and learning strategies in engineering education. This study was conducted with 273 first-year students in two universities in Korea. Following were the results: First, there were Sensing learners(72.2%), Visual learners(84.6%), Reflective learners(64.8%), and Sequential learners(58.2%) and the level of learning strategies was 3.28(SD=0.38). Secondly, the finding revealed that there was only significant difference in learning strategies on Information processing dimension and Active students demonstrated higher level of learning strategies than Reflective students. To be more specific, there were significant differences in cognitive, meta-cognitive, and internal and external management. For engineering education, implications for teaching strategies in classroom and self-regulated learning strategies were discussed.

• YAKHAK HOEJI
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• v.60 no.2
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• pp.92-99
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• 2016

Parkinson's disease (PD) is one of the representative neurodegenerative movement disorders with the selective loss of dopaminergic neurons in the substantia nigra. 6-Hydroxydopamine (6-OHDA) is widely used as an experimental model system to mimic PD and has been reported to cause neuronal cell death via oxidative and/or nitrosative stress. Therefore, daily intake of dietary or medicinal plants which fortifies cellular antioxidant capacity can exert neuroprotective effects in PD. In the present study, we have investigated the protective effect of Korean red ginseng (KRG) against 6-OHDA-induced nitrosative death in C6 glioma cells. Treatment of C6 cells with 6-OHDA decreased cell viability and increased expression of inducible nitric oxide synthase, production of nitric oxide as well as peroxynitrite, and formation of nitrotyrosine. 6-OHDA led to apoptotic cell death as determined by decreased Bcl-2/Bax, phosphorylation of JNK, activation of caspase-3, and cleavage of PARP. Conversely, pretreatment of C6 cells with KRG attenuated 6-ODHA-induced cytotoxicity, apoptosis, and nitrosative damages. To further elucidate the molecular mechanism of KRG protection against 6-OHDA-induced nitrosative cell death, we have focused on the cellular self-defense molecules against exogenous noxious stimuli. KRG treatment up-regulated heme oxygenase-1 (HO-1), a key antioxidant enzyme essential for cellular defense against oxidative and/or nitrosative stress via activation of Nrf2. Taken together, these findings suggest KRG may have preventive and/or therapeutic potentials for the management of PD.

• Journal of the Korean Dietetic Association
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• v.15 no.3
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• pp.278-285
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• 2009

The purpose of this pilot study was to examine the feasibility of using digital pictures to assess individuals' nutrient intakes from school lunch. The subjects for the study were 29 male students and 40 female students from two classes in a middle school located in Daejeon Metropolitan City, Korea. The school lunch service was self-operated and the students were allowed to portion the foods by themselves. The teacher in charge of each class took digital pictures of every student's lunch plate that was tagged with an i.d. number, before and after eating for two consecutive days. The researchers estimated the amount of food, which an individual actually consumed by comparing pre- and post-pictures of their plate with reference food pictures for better visual estimation of the food amounts. Individual energy and nutrient intakes were calculated using CAN-Pro (ver 3.0) using the food intake data visually estimated from the digital pictures and school lunch recipes. The teachers in charge reported that about 10~15 additional minutes were needed to take the pictures used for the study and this additional time did not place much burden on the service process during the lunch period. The results showed that the students' actual energy and nutrient intakes from the same school lunch menus were quite varied as the serving portions were not regulated and left-overs were not prohibited. This pilot study suggests that examination of individual nutrient intake using digital picture is a feasible method in the context of school lunch service.

• 전자공학회논문지 IE
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• v.48 no.1
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• pp.36-44
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• 2011

The purpose of this study was to develop the basic design principles for the engineering mathematics teaching model that supported college students to become collaborative problem solvers. For this purpose, the following four design principles were drawn from the steps of systems approach, especially with consideration of needs of engineering students, professors, curriculum and relevant research on mathematical education. As a result, the four design principles for the engineeering mathematics teaching model were drawn as follows: (1) Improve students' basic mathematical learning abilities through repetition and elaborative practice of the basic mathematical concepts and principles, (2) Develop students' problem solving abilities through collaborative projects or learning activities with peers, (3) Facilitate students' reflection and provide teacher's monitoring and prompt feedback during their learning process, and (4) Build up online learning environments that enable students to become self-regulated learners.

• Fire Science and Engineering
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• v.29 no.1
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• pp.19-26
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• 2015

This study covers securing legal systems and institutions regarding the standards for installing fire prevention facilities to prevent fire on wooden architectural heritage. Conflicts among relevant laws were revealed and problems related to fire prevention performance, technical standards, responsibilities, etc. in the process of establishing legal fire prevention equipment and the equipment for self-extinguishing were identified through pondering over current legal systems of fire prevention facilities. To resolve the problems, at least the principle to preserve original shapes of wooden architectural heritage should be secured even though fire prevention facilities are installed and the installation process should be regulated by laws considering features of fire on wooden architectural heritage so that fire prevention performance can be guaranteed. The directions to improve installing system through legalization of design, construction, and audit review institutions and legalization of the technical standards for fire prevention facilities were suggested to guarantee performance when establishing fire prevention facilities for wooden architectural heritage.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.1
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• pp.12-21
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• 2018

Objectives : Inflammation is one of the self-protective abilities against tissue injury, and it has clinical symptoms like redness, heat, swelling, pain, and loss of function. The purpose of this study is to examine inhibitory effects of Naetakchunkeum-san (NTCKS) on nitric oxide (NO), Prostaglandin E2 (PGE2), inducible NOS (iNOS), cyclooxygenase-2 (COX-2), and phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), which play a major role in inflammatory response. Methods : The experiment was performed using Raw 264.7 cells pretreated with NTCKS extracts. Cell viability was determined by MTT assay. To evaluate anti-inflammatory effects of NTCKS, we examined NO and $PGE_2$ production in LPS-induced macrophages. We also investigated effects of NTCKS on iNOS, Cox-2, and ERK1/2 expression using western blot. Results : In MTT assay, no cytotoxicity of NTCKS (50, 100, 150, $200{\mu}g/ml$) on RAW 264.7 cell was found. LPS-induced NO production was decreased after treatment with NTCKS (150, $200{\mu}g/ml$)(p<0.05). $PGE_2$ was decreased after treatment with NTCKS (150, $200{\mu}g/ml$)(p<0.05). NTCKS inhibited LPS-induced expressions of iNOS and COX-2 in a dose-dependent manner. Increased phosphorylation of ERK1/2 by LPS was decreased by NTCKS in a dose-dependent manner. Conclusions : According to above experiments, NTCKS may be applied to inflammatory diseases such as atopic dermatitis, rheumatoid arthritis, and inflammatory bowel disease.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.320-325
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• 2018

Hepatitis E virus (HEV) infection accounts for 20 million annual infections worldwide. HEV can be fatal in approximately 20-30% of pregnant women. HEV infections are normally self-limiting and mostly asymptomatic. However, in patients with insufficient immunity, such as acquired immunodeficiency syndrome patients, chronic and often fatal infections may ensue. Therefore, it is likely that host immune responses, especially interferon responses, play a critical role in HEV infection control. Here, we report that an HEV-encoded non-structural protein down-regulates type I interferon response. In addition, some other immune genes involved in the induction of type I interferon may be regulated as well. Detailed molecular mechanisms are currently being studied.