• Journal of Periodontal and Implant Science
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• v.26 no.4
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• pp.949-965
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• 1996

The main goal of periodontal therapy is to restore the lost periodontal tissue and establish the attachment appratus. Current acceptable therapeutic techniques are included : removal of diseased soft tissue, demineralization of exposed root surface, using the barrier membrane for preventing the downgrowth of gingival epithelial cell, insertion of graft materials as a scaffolding action, and biological mediators for promoting the cell activity. The latest concept one among them has been studied which based on the knowledge of cellular biology of destructed tissue. Platelet-derived growth factor(PDGF) is one of the polypeptide growth factor which have been reported as a biological mediator to regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purposes of this study is to evaluate the influences of the PDGF as biological mediator to periodontal ligament and bone marrow cell. Both right and left maxillary first molar were extracted from rat which had treated with 0.4% ${\beta}-Aminopropionitril$ for 5 days, and feeded until designed date to sacrifice under anesthesisa. Periodontal ligament were removed from the extracted socket of the rat, and cultured with Dulbecco's Modified Essential Medium(DMEM) contained with 10% Fetal Bovine Serum, 100U/ml penicillin, $100{\mu}g/ml$ streptomycin, $0.5{\mu}g/ml$ amphotericin-B. Bone marrow cell were culture from bone marrow suspension with which washed out from femur with same medium. The study was performed to evaluate the effect of PDGF to periodontal ligament and bone cell, cell proliferation rate, total protein synthesis, and alkaline phosphatase activity of rat periodontal ligament(PDL) cell and bone stromal(RBS) cell in vitro. The effects of growth factors on both cells were measured at 3, 5th day after cell culture with (control group) or without growth factors(experimental group). The results were as follows: 1. The tendency of cell proliferation under the influence of PDGF showed more rapid proliferation pattern than control at 3 and 5 days after inoculation. 2. The activity of Alkaline phosphatase revealed 14, 80% increased respectively at 3, 5 days culture than control group. Measurements of ALPase levels indicated that PDL cells had significantly higher activity when compared with that of co-culture groups and GF only(P<0.05). And, ALPase activity in 10 days was higher than that of 7 days(P<0.05). 3. The tendency of formation of the mineralized nodule were observed dose-depend pattern of PDL cells. There was statistically significant difference among group l(PDL 100%), 2(PDL 70%:GF 30%), and 3(PDL 50%:GF 50%)(P<0.01). But, there was no difference among group 3, 4(PDL 30%:GF 70%), and 5(GF 100%). 4. Also, the number of nodule was greater in co-culture of PDL 70% and GF 30% than in culture of PDL 70%(P<0.05). From the above results, it is assumed that the PDGF on PDL cells and RMB cell culture. GF stimulates the cell growth, which is not that of PDL cells but GF. And, the activity of ALPase depends on the ratio of PDL cells, and ALPase may relate to the initial phase of nodule formation. Also, it is thought that the calcified nodule formation principally depends on PDL cells, is inhibited by GF, and affected by cell density. In conclusion, platelet-derived growth factor can promote rapid osteogenesis during early stage of periodontal tissue regeneration.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.436-447
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• 2004

Wetland plants have evolved specialized adaptations to survive in the low-oxygen conditions associated with prolonged flooding. The development of internal gas space by means of aerenchyma is crucial for wetland plants to transport $O_2$ from the atmosphere into the roots and rhizome. The formation of tissue with high porosity depends on the species and environmental condition, which can control the depth of root penetration and the duration of root tolerance in the flooded sediments. The oxygen in the internal gas space of plants can be delivered from the atmosphere to the root and rhizome by both passive molecular diffusion and convective throughflow. The release of $O_2$ from the roots supplies oxygen demand for root respiration, microbial respiration, and chemical oxidation processes and stimulates aerobic decomposition of organic matter. Another essential mechanism of wetland plants is downward water movement across the root zone induced by water uptake. Natural and constructed wetlands sediments have low hydraulic conductivity due to the relatively fine particle sizes in the litter layer and, therefore, negligible water movement. Under such condition, the water uptake by wetland plants creates a water potential difference in the rhizosphere which acts as a driving force to draw water and dissolved solutes into the sediments. A large number of anatomical, morphological and physiological studies have been conducted to investigate the specialized adaptations of wetland plants that enable them to tolerate water saturated environment and to support their biochemical activities. Despite this, there is little knowledge regarding how the combined effects of wetland plants influence the biogeochemistry of wetland sediments. A further investigation of how the Presence of plants and their growth cycle affects the biogeochemistry of sediments will be of particular importance to understand the role of wetland in the ecological environment.

• Management & Information Systems Review
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• v.31 no.2
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• pp.41-59
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• 2012

ERP is a new technique of process innovation. It indicates enterprise resource planning whose purpose is an integrated total management of enterprise resources. ERP can be also seen as one of the latest management systems that organically connects by using computers all business processes including marketing, production and delivery and control those processes on a real-time basis. Currently, however, it's not easy for local enterprises to have operators who will be in charge of ERP programs, even if they want to introduce the resource management system. This suggests that it's urgently needed to train such operators through ERP education at school. But in the field of education, actually, the lack of professional ERP instructors and less effective learning programs for industrial applications of ERP are obstacles to bringing up ERP workers who are competent as much as required by enterprises. In ERP, accounting is more important than any others. Accountants are assuming more and more roles in ERP. Thus, there's a rapidly increasing demand for experts in ERP accounting. This study examined previous researches and literature concerning ERP education, identified problems with current ERP education at college and proposed how to solve the problems. This study proposed the ways of improving ERP education at college as follows. First, a prerequisite learning of ERP, that is, educating the principle of accounting should be intensified to make students get a basic theoretical knowledge of ERP enough. Second, lots of different scenarios designed to try ERP programs in business should be created. In association, students should be educated to get a better understanding of incidents or events taken place in those scenarios and apply it to trying ERP for themselves. Third, as mentioned earlier, ERP is a system that integrates all enterprise resources such as marketing, procurement, personnel management, remuneration and production under the framework of accounting. It should be noted that under ERP, business activities are organically connected with accounting modules. More importantly, those modules should be recognized not individually, but as parts comprising a whole flow of accounting. This study has a limitation because it is a literature research that heavily relied on previous studies, publications and reports. This suggests the need to compare the efficiency of ERP education between before and after applying what this study proposed to improve that education. Also, it's needed to determine students' and professors' perceived effectiveness of current ERP education and compare and analyze the difference in that perception between the two groups.

• Journal of Science Education
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• v.42 no.1
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• pp.49-65
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• 2018

Astronomy is the subject that can easily draw students' interest in studying science, therefore plays an important role in developing scientific core competence. However, it is difficult to develop spatial thinking that is required in understanding astronomical concepts through the classroom lessons. Planetarium, along with the science museum, is one of the most representative informal educational institution where astronomical concepts can be taught beyond time and space constraints. In this study, we developed the astronomy education program that is operated in the planetarium and applied the program to the elementary, middle and high-school students to investigate the effects of the planetarium lesson compared to the classroom lesson. The duration of this research was about 8 months, and the number of the students involved is 761, including participants of the 1 night and 2 days camps in the Daegu National Science Museum. The newly developed planetarium lesson is comparable to the previous classroom lesson of which topics are cardinal points, constellation, and the rotation of the earth. Test items were developed to evaluate the understanding of the astronomical concepts. The study was conducted based on the pre- and post-test with non-equivalent groups design comparing classroom and planetarium lessons. The results of this study are as follows. First, planetarium lesson is more effective for understanding astronomical concepts such as the cardinal points, earth's rotation, and the constellation than classroom lesson. Second, planetarium has a positive effect irrespective of gender and previous knowledge. Third, planetarium for high school students has the same effect as additional observation activities followed by the classroom instruction. Therefore, planetarium can be used as an alternative, effective tool when night observation is not available. In summary, planetarium is an effective tool that helps students to understand the astronomical concepts.

• Natural Product Sciences
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• v.8 no.1
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• pp.1-15
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• 2002

An International Cooperative Biodiversity Group (ICBG) program based at the University of Illinois at Chicago initiated its activities in 1998, with the following specific objectives: (a) inventory and conservation of of plants of Cuc Phuong National Park in Vietnam and of medicinal plants of Laos; (b) drug discovery (and development) based on plants of Vietnam and Laos; and (c) economic development of communities participating in the ICBG project both in Vietnam and Laos. Member-institutions and an industrial partner of this ICBG are bound by a Memorandum of Agreement that recognizes property and intellectual property rights, prior informed consent for access to genetic resources and to indigenous knowledge, the sharing of benefits that may arise from the drug discovery effort, and the provision of short-term and long-term benefits to host country institutions and communities. The drug discovery effort is targeted to the search for agents for therapies against malaria (antimalarial assay of plant extracts, using Plasmodium falciparum clones), AIDS (anti-HIV-l activity using HOG.R5 reporter cell line (through transactivation of the green fluorescent protein/GFP gene), cancer (screening of plant extracts in 6 human tumor cell lines - KB, Col-2, LU-l, LNCaP, HUVEC, hTert-RPEl), tuberculosis (screening of extracts in the microplate Alamar Blue assay against Mycobacterium tuberculosis $H_{37}Ra\;and\;H_{37}Rv),$ all performed at UIC, and CNS-related diseases (with special focus on Alzheimer's disease, pain and rheumatoid arthritis, and asthma), peformed at Glaxo Smith Kline (UK). Source plants were selected based on two approaches: biodiversity-based (plants of Cuc Phuong National Park) and ethnobotany-based (medicinal plants of Cuc Phuong National Park in Vietnam and medicinal plants of Laos). At mc, as of July, 2001, active leads had been identified in the anti-HIV, anticancer, antimalarial, and anti- TB assay, after the screening of more than 800 extracts. At least 25 biologically active compounds have been isolated, 13 of which are new with anti-HIV activity, and 3 also new with antimalarial activity. At GSK of 21 plant samples with a history of use to treat CNS-related diseases tested to date, a number showed activity against one or more of the CNS assay targets used, but no new compounds have been isolated. The results of the drug discovery effort to date indicate that tropical plant diversity of Vietnam and Laos unquestionably harbors biologically active chemical entities, which, through further research, may eventually yield candidates for drug development. Although the substantial monetary benefit of the drug discovery process (royalties) is a long way off, the UIC ICBG program provides direct and real-term benefits to host country institutions and communities.

• Journal of Korean Home Economics Education Association
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• v.22 no.4
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• pp.109-138
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• 2010

This study examined how practical reasoning process is reflected in the 2007 revised home economics textbook of the 7th grade that is being used in schools since 2010. For a textbook analysis of the components of practical reasoning process, 12 published textbooks were all analyzed, and analysis areas were decided by reconstructing the textbook system into introduction, body contents, learning activities, evaluation. Analysis criteria were extracted from the previous literatures. Practical reasoning process was classified into Valued Ends, Context and Background, Alternatives and Means, on sequence, and Action and Reflection. As a result of analyzing categories and problems that practical reasoning process is reflected in the textbook, firstly, here was a category, which Valued Ends was absent in the practical reasoning process. In the relevant category, general problem solving progress and practical reasoning process could not be differentiated, and activity was developed with 'strategies for solution' as objective. Second, there was a category that the practical reasoning process was reflected in body contents. In this category, knowledge, concept, principle, and theory were insufficiently dealt with. Third, there was a category that reflected components of practical reasoning process but was covered with general problem solving process. Fourth, there was a category that described theme of sub-unit and body contents from the different curriculum perspectives. A curriculum perspective works as the foundation of preparing class contents or consistency of methods when developing lessons. Therefore, confusion might occur when a teacher plans a class with this kind of textbook. Fifth, a category that suggested partial components of practical reasoning process was shown the most and this category is difficult to maximize effects of practical reasoning process.

• 대한공업교육학회지
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• v.33 no.2
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• pp.192-217
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• 2008

This paper investigated the perceived criticalities and patterns of Korean Professional Engineer's competency regarding the working activities of automative product development, manufacturing, etc by using questionnaires responded to the survey which were applied to the automotive professors, experts and professional engineers (vocational parties) by e/mail, etc. This research investigated the following questions: First, what are the characteristic patterns, relevancy and perceived criticalities of Korean Professional Engineer's competencies? Second, What are the ranked priority of the Korean Professional Engineers' competencies? Are there any differency for each item, sub group of job, intelectual criterior of the competencies between relevancy and perceived criticalities according to the types of vocational parties, etc.? Accoring to the results; first, Professor group showed highest points among 3 groups per each item of the competencies by vocational parties Second, Chassis design group ranked top position among the 8 sub groups by vocational parties and, third, Problem Solving Knowledge ranked highest points than any others. Korean Professional Engineers are found to be positioned as key members, leaders and managers on surveying market, product planning, designing product & components, developing component parts, establishing shop with production equipment, managing quality control & material handling, organizing relevant meetings, developing human resources by training and learning, to back up finance with law matters, cooperating with concerned parties to achieve organizational goals, and to coordinate projects. etc, identifying ethical issues and business skills in order to survive and win to be competitive in various kinds of the automotive industry battle fields.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.197-209
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• 2018

Recently, many start-up failures occur as the number of attempts to start a business increases in a social atmosphere that encourages start-up. In particular, young entrepreneurs have a lower survival rate than general entrepreneurs because young entrepreneurs are challenging just with a simple idea to overcome the difficulties of employment while lacking prior knowledge and experience of business. Therefore, the reason for the failure of start-up is lack of preparation for start-up and lack of entrepreneurship. The purpose of this study is to develop a measurement tool to build a basic framework for entrepreneurship development and start - up preparation activities for young people. To develop an entrepreneurship measurement tool, researchers developed a preliminary question through qualitative research methods such as literature research, focus group interview, and expert verification. After that, researchers surveyed 102 entrepreneurs using quantitative research method and to verify the construct validity of the measurement tool, the final entrepreneurship measurement tool was completed through exploratory factor analysis and confirmatory factor analysis. The entrepreneurship measurement tool developed through this research process consists of 7 components and 15 measurement items. First, in the step of 'confirming entrepreneurial intention', two items of 'self-analytic competence', three items of 'ability of establishing start-up philosophy'are contained. Second, in the step of 'drawing up a start-up model', two items are contained in each category such as, 'ability of eliciting entrepreneurial idea,' 'ability of analyzing idea validity,' 'competence of planning a venture start-up model'. Third, in the step of 'planning the venture start-up,' two items are contained in each category such as, 'business-plan presentation competency,' 'ability of implementing organizational system.'. The measurement tool of entrepreneurship is meaningful as it could help young entrepreneur find out their lacking competence in preparing their start-ups and strengthen necessary competences by measuring their own entrepreneurship. Rather in the entrepreneurship education, basic data that can diagnose the entrepreneurship of young entrepreneurs is provided.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.101-115
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• 2000

This study aims to make a research on the secondary school education of geography and the system of teacher training in Belgium, focused on the case of Francophone Community. What has been made clear by this research can be summed up as follows. The first two years of the secondary school offer two hours of 'environment education', per week, which can be categorized into the learning of living geography, in that at this stage students learn how to observe the geographic phenomena in their daily life and pigeonhole them. The two years of the second stage of the secondary school offer one hour of 'world geography' which actually is focused on the district of Europe and Russia. The two years of the third stage of the secondary school offer an advanced course of geography which aims to teach systematically the physical geography and the human geography. A remarkable change in geographic education in Belgium is that in the wake of the Revision Act of the secondary school education, textbooks were replaced by other teaching manuals adapted to the regional condition by the teachers. This may result in a wide gap of achievements in geography according to the conditions of educational establishments. Another notable change is that the stress of geographic education tends to be placed on the ability of acquiring practical geographic knowledge rather than the geographic information itself. And it is also another marked tendency that most learning activities in geography class are conducted on the basis of student-centered and the method of investigation. Teachers of the lower secondary schools in Belgium are trained in the School of Education as multi-major teachers, such as a teacher for biology-chemistry-geography or a teacher for history-sociology-geography. Teachers of the higher secondary school education are trained in the Department of Teacher Education in universities as solo-major teachers in that they are required to know more deeply to teach an advanced course of geography in the higher secondary schools. To improve the teacher education many folds of policies are adopted. One is that many in-service teachers are officially put into services of guiding and teaching teacher training. Another is that faculty members in charge of teacher training course are trying to level up the qualifications of teachers by rigorous disciplining.

• Journal of Life Science
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• v.24 no.4
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• pp.343-351
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• 2014

Phosphoinositide 3-kinase (PI3K) plays a central role in cell signaling and leads to cell proliferation, survival, motility, exocytosis, and cytoskeletal rearrangements, as well as specialized cell responses, superoxide production, and cardiac myocyte growth. PI3K is divided into three classes; type I PI3K is preferentially expressed in leukocytes and activated by ${\beta}{\gamma}$ subunits of heterotrimeric G-proteins. In this study, the cDNAs encoding the $PI3K{\gamma}$ gene were isolated from a brain cDNA library constructed using the flounder (Paralichthys olivaceus). The sequence of the isolated $PI3K{\gamma}$ was 1341 bp, encoding 447 amino acids. The nucleotide sequence of the $PI3K{\gamma}$ gene was analyzed with that of other species, including Oreochromis niloticus and Danio rerio, and it turned out to be well conserved during evolution. The $PI3K{\gamma}$ gene was subcloned into the expression vector pET-44a(+), and expressed in the E. coli BL21 (DE3) codon plus cell. The resulting protein was expressed as a fusion protein of approximately 49 kDa containing a C-terminal six-histidine extension that was derived from the expression vector. The expressed protein was purified to homogeneity by His-tag affinity chromatography and showed enzymatic activity corresponding to $PI3K{\gamma}$. The binding of wortmannin to $PI3K{\gamma}$, as detected by anti-wortmannin antisera, closely followed the inhibition of the kinase activities. The results obtained from this study will provide a wider base of knowledge on the primary structure and characterization of the $PI3K{\gamma}$ at the molecular level.