• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.229-248
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• 1993

[ $Interferon-\gamma$ ] has been suggested as a cytokine of connective tissue stabilizer. In addition, it has also been demonstrated that this cytokine inhibited bone remodeling activities of the bone derived cells. In order to illuminate the effects of this cytokine in orthodontic force induced bone remodeling, it was administered to primary cultured periodontal ligament cells which have been known to have some osteoblast like characteristics. $Interferon-\gamma$ slightly decreased $[^3H]thymidine$ incorporation rate without a significant change in the total cellular DNA content up to 1000 U/ml, which meant these doses were not cytotoxic to the cell. Total protein synthesis was not influenced by various concentration of interferon-y whether it was determined by the $[^3H]proline$ incorporation rate or by the Lowry smethod. The effect of $interferon-\gamma$ on the individual protein was, however, differential, ie, it increased $[^3H]proline$ incorporation into the noncollagenous protein marginally, while it decreased $[^3H]proline$ incorporation into the collagen, so that it caused dose-dependent suppression of the relative collagen synthesis. On the contrary, the fibronectin synthesis determined by the ELISA was increased by 1000 U/ml of $interferon-\gamma$. The differential effects of the interferon-y on the collagen and fibronectin synthesis exhibited not only their protein level but also the steady state mRNA level. $Interferon-\gamma$ decreased steady state level of ${\alpha}1(I)$ procollagen mRNA significantly, while showing no significant changes in the fibronectin mRNA level. In addition to this, it was also found that indomethacin did not affect on the $interferon-\gamma$ induced collagen decrease in this cell, which meant prostaglandins were not involed in the process of $interferon-\gamma$ induced collagen decrease. So it can be concluded that the incubation of periodontal ligament cells with 1000 U/ml of $interferon-\gamma$ for 24 hr showed differential effects on the type I collagen and fibronectin gene expression. The decrease in relative collagen synthesis in the protein level was related with decrease in the steady state level of mRNA, while the increase in the fibronectin synthesis in the protein level was not correlated with the mRNA level.

• Journal of Korean Library and Information Science Society
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• v.49 no.3
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• pp.55-75
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• 2018

The purpose of this study is to identify characteristics of secondary school teachers' perceptions and experiences of school libraries and to suggest strategies for its' activation. In order to achieve this aim, the questionnaire survey was conducted for 229 secondary school teachers who participated in K university qualification training in 2017. As a result, they recognize that school libraries are an essential facility and that continuous support and investment are needed. They think that the effectiveness of the school library is very helpful for creating a leisure and cultural life and for stimulating reading atmosphere and education, and this perception is stronger at lower ages. The number of school library use of them is as low as once a month, and the purpose of use is mainly for cultivation and leisure. The discomfort of the school library is mostly due to lack of materials and space for them. In particular, they have a lack of knowledge and necessity about the method of library-based instruction and insufficient preparation time and poor materials. Teachers are highly aware of the need and utility of training, and prefer training with peers. Therefore, it is necessary to develop strategies such as remodeling space and increasing collections for their study and instruction, and foster peer supervision so that they can actively utilize school library in subjects management.

• Journal of Periodontal and Implant Science
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• v.44 no.1
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• pp.13-19
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• 2014

Purpose: The purpose of this study was to retrospectively evaluate the survival of periodontally hopeless teeth that were intentionally extracted and replanted after a delay and to compare the radiographic characteristics of the survival group with those of the failure group. Methods: The clinical and radiographic data from patients who underwent delayed intentional replantation between March 2000 and July 2010 were reviewed. Twenty-seven periodontally hopeless teeth were extracted and preserved in medium supplemented with antibiotics for 10-14 days. The teeth were then repositioned in the partially healed extraction socket and followed for 3 to 21 months. The radiographic parameters were analyzed using a paired t test and the cumulative survival rate was analyzed using Kaplan-Meier analysis. Results: Seven replanted teeth failed and the overall cumulative survival rate was 66.4%. In the survival group, the amount of bone loss was reduced from 68.45% to 34.66% three months after replantation. There was radiologic and clinical evidence of ankylosis with 5 teeth. However, no root resorption was found throughout the follow-up period. In the failure group, bone formation occurred from the bottom of the socket. However, a remarkable radiolucent line along the root of a replanted tooth existed. The line lengthened and thickened as time passed. Finally, in each case of failure, the tooth was extracted due to signs of inflammation and increased mobility. Conclusions: Delayed intentional replantation has many advantages compared to immediate intentional replantation and could serve as an alternative treatment for periodontally involved hopeless teeth. However, techniques for maintaining the vitality of periodontal structures on the tooth surface should be developed for improved and predictable results.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.97-109
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• 2008

This study first attempted to catch the transformational affairs and motives of the representative pavilion, Hanbyeok in Honam after its construction. Especially, it re-illuminated the morphologic, significant and functional change process of a pavilion after the early Joseon Dynasty by taking the local scenery, Hanbyeokdang as a sample, and considering the space and scenic characteristics, and diachronically understood its creation process and rebuilt its inherent positional meaning to reach the following conclusion. 1. Weoldanglu, at its early foundation, seems to have stressed the function of a private banquet and lecture hall to train younger students, and served as a reception space. Then the reception function gradually increased, and up to before 1530, it seems to have been called Weoldanglu(月塘樓) or Weoldangwon(月塘院). 2. In 1619, Governor Yoo Saek changed the pavilion name to Hanbyeokdang through the subject of a poem. 200 years after Weoldang's death, it became a public space called Hanbyeokdang, an amusement place in which scholars cultivated great morale, and participated in the sending-off and welcoming of predecessors and successors. This seems to have taken a foothold as a public event or entertainment space for the local administration, Jeonjuboo(全州府) through the remodeling process sponsored by the public. 3. Scenic language such as its indicating name, expression type and surrounding view through old map and so on, the shape of Hanbyeokdang evolved and changed to diverse types after the foundation of Weoldanglu, at the heart of which Hanbyeokdang with its two legs standing at a rock was located. 4. During the late 18th century, Hanbyeokdang seems to have been a wing corridor connected closely to the left corridor of the Jeonju stream bed, whose pattern is presumed to have existed even during the early 19308. Such changes in scenic language make us assume that diverse auxiliary space, a wing corridor, was erected for use as a public banquet and amusement spot of Jeonjuboo Castle, the inherent function of Hanbyeokdang after the mid 18th century. 5. Penetration of Hanbyeokgool and the erection of Hanbyeokgyo caused the change of the ancient shape of Hanbyeokdang. Specifically, a great Hanbyeokgyo passing by the pavilion changed the relative scale, so the pavilion image of pursuing unity with nature has lost the old inherent refinement and visual character.

• Land and Housing Review
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• v.5 no.4
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• pp.225-234
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• 2014

Because of their nature as public facilities, demands that former military facilities be utilized for the public welfare are increasing, thereby leading to an increase in cases in which these military facilities are reestablished as parks. Cases in which former military bases were reestablished as public parks were analyzed; as a result, several implications were derived. First, the objectives of public park projects should be examined from the perspective of the concept of urban regeneration and regional revitalization. Moreover, it is necessary that profits are yielded and that regional identity and history are reproduced through reusing existing facilities as much as possible rather than entirely remodeling former military sites. As parks become larger in size, bases should be reorganized into complexes rather than single facilities or programs. It is also necessary that parks be established in stages considering the enormous expenses required for building public parks. Consequently, because the special characteristics of military facilities can lead to insufficient on-site investigation in the process of establishing parks, thereby incurring a vast amount of costs for design adjustment and contamination disposal, this should be considered in advance. A method of delegating the development rights to partial sites to private businesses and supplementing the costs of park establishment and maintenance with development benefits should be examined. In addition, given that there are various interests and stakes in former military bases, a method of operating a public-private cooperative decision-making organization during project execution should be considered. Finally, policies related to urban parks need to be improved in order to raise funds, expand profitable businesses, facilitate social services and sponsorship, and encourage the participation of trusts and non-profit organizations in park operation and management.

• Journal of Life Science
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• v.30 no.7
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• pp.651-659
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• 2020

Cardiovascular disease is one of the leading causes of death across the world, and gold-standard treatments such as percutaneous coronary intervention and artery bypass grafting have various limitations including myocardial damage and subsequent maladaptive cardiac remodeling. To overcome this, stem-cell therapies are emerging as a promising strategy for cardiovascular regeneration. Endothelial progenitor cells (EPCs) have high potential to proliferate and differentiate into endothelial cells for vascularization and tissue regeneration, and several clinical trials have explored EPC function in tissue repair in relation to clinical safety and improving cardiac function. Consequently, EPC has been suggested as a feasible stem-cell therapy. However, autologous EPC transplantation in cardiovascular disease patients is restricted by risk factors such as age, smoking status, and hypertension that lead to reduced bioactivity in the EPCs. New approaches for improving EPC function and stem-cell efficacy have therefore been suggested, including cell priming, organoid culture systems, and enhancing transplantation efficiency through 3D bioprinting methods. In this review, we provide a comprehensive understanding of EPC characteristics, therapeutic approaches, and the current state of clinical research into EPCs as stem-cell therapy for cardiovascular disease.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.373-384
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• 2008

Purpose: The aim of this study is to compare the healing response of various Hydroxyapatite(HA) coated dental implants by Ion-Beam Assisted Deposition(IBAD) placed in the surgically created circumferential gap in dogs. Materials and methods: In four mongrel dogs, all mandibular premolars and the first molar were extracted. After an 8 weeks healing period, six submerged type implants were placed and the circumferential cylindrical 2mm coronal defects around the implants were made surgically with customized step drills. Groups were divided into six groups : anodized surface, anodized surface with 150nm HA and heat treatment, anodized surface with 300nm HA and heat treatment, anodized surface with 150nm HA and no heat treatment, and anodized surface with 150nm HA, heat treatment and bone graft, anodized surface with bone graft. The dogs were sacrificed following 12 weeks healing period. Specimens were analyzed histologically and histomorphometrically. Results: During the healing period, healing was uneventful and implants were well maintained. Anodized surface with HA coating and $430^{\circ}C$ heat treatment showed an improved regenerative characteristics. Most of the gaps were filled with newly regenerated bone. The implant surface was covered with bone layer as base for intensive bone formation and remodeling. In case that graft the alloplastic material to the gaps, most of the coronal gaps were filled with newly formed bone and remaining graft particles. The bone-implant contact and bone density parameters showed similar results with the histological findings. The bone graft group presented the best bone-implant contact value which had statistical significance. Conclusion: Within the scope of this study, nano-scale HA coated dental implants appeared to have significant effect on the development of new bone formation. And additional bone graft is an effective method in overcoming the gaps around the implants.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.189-207
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• 1988

In almost all biologic systems, mechanically induced electric charge separation is a fundamental phenomenon. Since the hypothesis was established that the generation of electric potentials in bone by mechanical stress including muscular force might control the activity in bone by mechanical stress including muscular force might control the activity of osseous cells and their biopolymeric byproduct, the concept of electrically mediate growth mechanism, which involves biological growth and bone remodeling by any means, in living systems has been applied clinically and experimentally to orthopedic fracture repair, the regulation of orthodontic tooth movement, epiphyseal cartilage regeneration, etc. On the other hand, recent numerous research data available show apparently that the mandibular condyle has the characteristics of growth center as well as growth site. In addition, there exists a considerable difference of opinion as to the role of external pterygoid muscle in condylar growth. In view of these evidences, this. experiment was performed to investigate the effect of the galavic current on the growth of the mandible and condyle for elucidating the nature of condylar growth. The bimetallic device was composed of silver and platinum electrode connected with resistor (3.9 Mohm), which was expected to produce galvanic current of 23.6 nA according to the galvanic principle. The 25 Sprague-Dawley rats were divided into two group, 2 week group comprising 8 animals exposed to satanic current for 2 weeks and 3 control animals not exposed for 2 weeks, 4 week group comprising 10 animals in experimental group and 4 animals in control group applied for 4 weeks respectively. The experimental rats were subjected to application of the galvanic current invasively to codylar head surface and the control groups with sham electrode. On the basis of anatomic and histologic data from the mandibular condyle of experimental and control group, the following results were obtained. 1. After 2 weeks, there was no increase of mandibular size in experimental group over that of the control group. 2. After 4 weeks, the size of the condylar head was larger in experimental group than that of the control. 3. In 2 week group, the thickness of the mitotic compartment and hypertrophic chondroblastic layer was increased in experimental group. 4. In 4 week group, the number and the size of the hypertrophic chondroblasts were increased significantly on experimental group over that of the control group. 5. The application of the satanic current caused an increase in chondrocytic hypertrophy and intercellular matrix in both groups.

• Journal of muscle and joint health
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• v.12 no.2
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• pp.155-165
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• 2005

Arthritis is one of the most common chronic degenerative joint disease in elderly. Osteoarthritis is a widespread, slowly developing disease, with a high prevalence increasing with age in women. The large joints mostly involved by the disease are the knees. But there are no treatments available that cure the underlying process of osteoarthritis diseases. Physical exercise helps in increasing cartilage nutrition and remodeling, increases the synovial blood flow, decrease swelling, and improves muscle strength. Thus, exercise has been suggested as an important nursing strategy in osteoarthritis. Purpose: The purpose of this study were to compare muscle strength between Tai-Chi exercise and aquatic exercise for women with knee osteoarthritis. Methods: A quasi-experimental study with pretest and posttest measures was used. The study subjects were those who had been enrolled in a community health center, and agreed to participate in the study for eight weeks, signed the consent form, and obtained the physicians approval. The study dropout rates were 13.2% with the final study subjects of 17 on Tai-Chi exercise, 16 on aquatic exercise program. The collected data were analyzed using SPSS for Window (version 12.0). Independent sample t-test and paired t-test was performed to compare of muscle strength for women with osteoarthritis after 8-week Tai-Chi exercise and aquatic Exercise. Results: The homogeneity tests of demographic characteristics and study variables at the pretest data revealed no significant differences between two groups. After 8-week Tai-Chi and aquatic exercise, there was significant result in pre-post test comparison on muscle strength on Tai-Chi group, but no significant in aquatic group. There were no significant differences of knee extensor (p=.078), and hand grip(p=.118) in group comparisons on muscle strengths. But there were significant differences of knee flexor(p=.024). Conclusion: Tai-chi exercise was effective in improving knee flexor. So, it seems that Tai-chi exercise may be more suitable for aquatic exercise in osteoarthritis exercise programs. Further studies with other comparisons in physical and psycho social outcomes are necessary to confirm the more effects of exercise.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.351-360
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• 2015

Human influence on soil formation has dramatically increased with human civilization and industry development. Increase of anthropogenic soils induced researches on the anthropogenic soils; classification, chemical and physical characteristics of anthropogenic soils and plant growth from anthropogenic soils. However there have been no comprehensive analyses on soil pore or physical properties of anthropogenic soils from 3 dimensional images in Korea. The objectives of this study were to characterize physical properties of anthropogenic paddy field soils by depth and to find differences between natural and anthropogenic paddy field soils. Soil samples were taken from two anthropogenic and natural paddy field soils; anthropogenic (A_c) and natural (N_c) paddy soils with topsoil of coarse texture and anthropogenic (A_f) and natural (N_f) paddy soils with topsoil of fine texture. The anthropogenic paddy fields were reestablished during the Arable Land Remodeling Project from 2011 to 2012 and continued rice farming after the project. Natural paddy fields had no artificial changes or disturbance in soil layers up to 1m depth. Samples were taken at three different depths and analyzed for routine physical properties (texture, bulk density, etc.) and pore properties with computer tomography (CT) scans. The CT scan provided 3 dimensional images at resolution of 0.01 mm to calculate pore radius size, length, and tortuosity of soil pores. Fractal and configuration entropy analyses were applied to quantify pore structure and analyze spatial distribution of pores within soil images. The results of measured physical properties showed no clear trend or significant differences across depths or sites from all samples, except the properties from topsoils. The results of pore morphology and spatial distribution analyses provided detailed information of pores affected by human influences. Pore length and size showed significant decrease in anthropogenic soils. Especially, pores of A_c had great decrease in length compared to N_c. Fractal and entropy analyses showed clear changes of pore distributions across sites. The topsoil layer of A_c showed more degradation of pore structure than that of N_c, while pores of A_f topsoil did not show significant degradation compared with those of N_f. These results concluded that anthropogenic soils with coarse texture may have more effects on pore properties than ones with fine texture. The reestablished paddy fields may need more fundamental remediation to improve physical conditions.