• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.116-122
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• 2014

Total of fifty accessions of Brassica rapa with various morphological characteristics were used for production of double haploid plants though microspore culture in Brassica rapa. Among them, only 30 accessions induced embryos from microspores. The highest efficiency of embryo induction of 1.194 per bud was obtained from IT135449 of turnip type, while 3 accessions of sarson (winter oil) type did not generate embryo. The effect of heat shock periods for embryogenesis was also investigated with 4 accessions (IT135449; Turnip type, IT199710; Chinese cabbage type, IT212886; Pak choi type, IT218043; Summer oil type). The high productions of embryos were observed in IT135449, IT199710 and IT212886 when microspores were pre-cultured to $32^{\circ}C$ for 2 days. In IT218043, high embryogenesis was observed at the 3 days of heat shock treatment. The optimal condition of shoot regeneration for IT199710 was observed in MS medium supplemented with NAA $0.5mg{\cdot}L^{-1}$ and BAP $1mg{\cdot}L^{-1}$. In contrast, the IT135449 and IT212886 were observed high regeneration frequency in MS medium without plant growth regulators. All the plantlets regenerated from microspore-derived embryos have been successfully transplanted to soil, and bud self-pollinated seeds were produced from doubled haploid plants. This indicated that double-haploid genotype was likely generated naturally during embryogenesis process.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.79-84
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• 2012

An efficient protocol for cryopreservation of madder hairy root cultures has been developed using droplet-vitrification. In previous study, combining loading solution C4 (35% PVS3) and vitrification solution B5 (80% PVS3) was the most effective method. In this study, we tried three types of vitrification solution, B5, A3 (90% PVS2, on ice), and A5 (70% PVS2, on ice). Combining loading solution C4 and vitrification solution A5 (on ice) showed the best regeneration rate in this study. Histological changes of the cells within the hairy root of madder were also observed in different steps. The cells from the hairy roots of the control treatment were full and intact with different size of vacuoles and obvious cell nucleus having a dark nucleolus. After the stage of preparing for cryopreservation (after preculturing, loading, followed by dehydration solution A5 or B5), intercellular spaces had become distinct, and within cells, the cytoplasms had become denser and week plasmolyses had appeared. The cell plasmolyses were much more apparent and we measured the degree of plasmolysis by calculating, the area of cell/the area of cytoplasm. The value of plasmolysis degree was the highest in the combination of preculture, loading solution C4, and dehydration solution A5, 1.97. Because the highest regeneration rates appeared in the treatment of A5 for 20 min, we could assume that the optimal degree of plasmolysis for cryopreservation might be around 1.97. The changes in cell structure during cryopreservation might be a useful basis for the development of a proper long-term preservation method for madder germplasms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.151-159
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• 2020

This study examined the environment and landscape aspects of rural villages, which are based on agriculture, to regenerate a disappearing rural village. The lifestyle and living conditions in this area were examined and the field survey of this area was carried out. The main negative factors at the rural landscape and living environment, such as rural households garbage, compost piles, and farming wastes, were found. An improvement plan of the landscape in this area was then determined. The disposal conditions according to the garbage types were analyzed through a survey with the residents directly. Through this survey, the current negative factors in landscape were checked and various improvement methods were assessed. Based on this, an institutional framework about landscape improvement of a village was developed, and a fundamental resource that can improve the environment of rural communities by this system is suggested.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.276-280
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• 1994

To obtain hybrids producing antagonisms and plant growth promoting effects by intergeneric nuclei transfer, the nuclei were isolated from the protoplasts of Trichoderma harzianum T95 and treated with colchicine. The nuclei were tranferred into protoplast of multi-auxotrophic Gliocladium virens G88 which cannot grow in minimal medium. The nuclei tranferred into protoplasts of G. virens G88 were selected on the regeneration minimal medium containing chloroneb as a haploid inducer. Low transfer frequency of 0.08% was observed with three chemical treatment, however no segregants were found in the intergeneric nuclei transfer. The various types of hybrids with different morphology were detected when different concentration of chloroneb were treated. These morphologies were classified as parental, recombinant and petite type.

• Journal of Plant Biotechnology
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• v.35 no.3
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• pp.235-243
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• 2008

Here we describe a procedure for Chinese cabbage protoplast culture and effects of various treatments. Chinese cabbage protoplasts were isolated from different parts of young seedlings as using an enzyme mixture, of which yield was maximized in seven hours around after digestion. The highest rate of initial cell division followed by micro-callus formation was obtained in the medium with 1.0 mg/L 2,4-D, 0.5 mg/L NAA, and 1.0 mg/L BA when the cotyledon-derived protoplasts were cultured. Initiation of cell division and micro-callus proliferation significantly depended upon Chinese cabbage genotype under a same culture circumstances. The micro-calli developed from cotyledon tissue of Norang-Bom cultivar successfully grew toward callus colonies on the solidified medium with 0.2 mg/L zeatin and 0.1 mM spermidine. The callus colonies generated de novo shoots at the maximum frequency of 4.3% on the medium with 5.0 mg/L BA and 1.0 mg/L NM. Our results might be helpful for further studies to enhance the regeneration efficiency in Chinese cabbage protoplast culture.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.6
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• pp.459-466
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• 2011

Purpose: This study evaluated the capability of bone formation with silk fibroin/nano-hydroxyapatite/corn starch composite scaffold as a bone defect replacement matrix when grafted in a calvarial bone defect of rabbits $in$ $vivo$. Methods: Ten New Zealand white rabbits were used for this study and bilateral round-shaped defects were formed in the parietal bone (diameter: 8.0 mm). The silk fibroin 10% nano-hydroxyapatite/30% corn starch/60% composite scaffold was grafted into the right parietal bone (experimental group). The left side (control group) was grafted with a nano-hydroxyapatite (30%)/corn starch (70%) scaffold. The animals were sacrificed at 4 weeks and 8 weeks. A micro-computerized tomography (${\mu}CT$) of each specimen was taken. Subsequently, the specimens were decalcified and stained with Masson's trichrome for histological and histomorphometric analysis. Results: The average ${\mu}CT$ and histomorphometric measures of bone formation were higher in the control group than in the experimental group at 4 weeks and 8 weeks after surgery though not statistically significant ($P$ >0.05). Conclusion: The rabbit calvarial defect was not successfully repaired by silk fibroin/nano-hydroxyapatite/corn starch composite scaffold and may have been due to an inflammatory reaction caused by silk powder. In the future, the development of composite bone graft material based on various components should be performed with caution.

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.2
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• pp.17-24
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• 2017

The study aims to investigate problems underlying in an old local house in Iksan, Jeollabuk-do and hence improve performance and remodel the house. Based on a survey regarding current conditions of the house and several case studies on other successful renovation projects, this study suggests new renovation concepts for the old house into a guest house. The study analyzes the current state of Iksan in which the location is faced with population decline - especially among the young - and the lack of community facilities and infrastructure, and finally the unfavorable situation in the residential environment. the case study involves four successful renovated guest house projects: three renovated old single houses in Seoul and Jeonju, and a renovated old Japanese housing complex in Kunsan. The renovating concepts for the local old house is as follows: renovating for performance improvement (i.e. lighting, ventilation, heating, plumbing, insulation, structure, and water proofing), utilizing the local house to a guest house for a growing number of tourists, adding new guest rooms, installing convenient facilities in order to provide better living environments for the visitors, and improving community and street landscapes.

• Journal of the Korean Institute of Rural Architecture
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• v.22 no.3
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• pp.41-48
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• 2020

The purpose of this research is to manage the physical sectors systematically, needed for the selection and direction of declining areas, such as urban regeneration and revitalization projects, by grading the density of decline indicators of buildings in small and medium cities. In five small and medium-sized cities in Jeollanam-do, the data were divided into three stages according to the density, according to the use, structure, and age of the building. Rating by element of Census Output Area, detailed designation, and management of declining areas in small and medium-sized cities are required, rather than setting the scope of declining areas based on administrative districts. It is also necessary to manage cities through complex and intra-element phasing rather than single elements in defining physical decline. The analysis based on the complex factors and boundary of the Census Output Area is meaningful in order to maintain and manage such cities in a more detailed and precise manner according to such characteristics of each region.

• Journal of Korean Society of Rural Planning
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• v.20 no.3
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• pp.21-31
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• 2014

The purpose of this study is to develop promotion strategies for revitalizing mountain eco-villages through social economic support. In order to fulfill this purpose, this study analyzed operation conditions, income creation structures of 240 mountain eco-villages formed by Korea Forest Service, and reviewed systems for social economic support. As summarized in research outputs, this study confirmed that the activities of organizations for joint projects had not been properly implemented due to the absence of supporting systems following the construction of mountain eco-villages. In addition, 159 villages formed as experience villages could not be qualified for enterprise systems due to aging population and absence of network systems. As for income creation, as indicated by comparing net incomes for joint projects calculated based on the classification of village management evaluation, the average net income of 51 highly-rated villages was 22 million Won and that of 128 moderately-rated villages was 3.5 million Won. Experience-based projects and the sales of processed forestry products made by young adult associations or women's societies were major sources of income, and the absence of inner economic bases or villages' jobs caused young adults and returned farmers to focus on working for outside economic activities. Finally, this study developed strategies for mountain eco-village's social economic promotion and suggested four stages of social economic revitalization provisions.

• Journal of the Korean Institute of Rural Architecture
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• v.22 no.4
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• pp.43-50
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• 2020

The purpose of this study is to extract deficiency areas as basic data of policies and projects in the future Living SOC introduction and planning. In order to extract living SOC deficient areas, accessibility data for living SOC and density data for main users by facility were overlapped, focusing on the living SOC indicators presented in the National Urban Regeneration Basic Policy. According to the analysis of accessibility of the Iksan-si Living SOC, the gap between deficiency in urban and township areas was large in common with the accessibility of the village and local base units. As a result of overlapping life SOC accessibility data and density data analysis of the main users by facility, areas where accessibility is weak but not inhabited by the main users of each facility were extracted. It is meaningful that more accurate deficient areas can be extracted by simultaneously utilizing the density distribution of the main users, rather than simply accessing the facilities.