• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2003년도 제40회 국제학술심포지움
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• pp.28-37
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• 2003

Tissue engineering and stem cells show potentials to restore lost or malfunctioning human tissues or organs. Another cell source for tissue engineering of cardiovascular tissues is stem cell. This study reports the development of cardiovascular tissues using tissue engineering and mesenchymal stem cells. The blood vessels and heart valves were fabricated by culturing mesenchymal stem cells on biodegradable synthetic or natural matrices. Bone marrow was isolated from dogs or rats and mesenchymal stem cells were cultured. The cells were seeded onto biodegradable synthetic or natural matrices and implanted in dogs. Histological and immunohistochemical analyses were performed to examine the regenerated cardiovascular tissues. Histological and immunohistochemical analyses showed the complete regeneration of blood vessels and heart valves. Fluorescent labeling of cells prior to implantation and fluorescence examination of the regenerated tissues revealed that the implanted cells reconstituted the cardiovascular tissues. This study demonstrates the potential of tissue engineering and mesenchymal stem cells for the regeneration of functional cardiovascular tissues or organs.

• Journal of Ecology and Environment
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• 제34권2호
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• pp.157-165
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• 2011

This study was conducted to determine the characteristics of gaps and natural regeneration of trees on Mt. Makiling, the Philippines. Canopy gaps in or around two 1-ha permanent plots and on 3-km line transects were investigated. Most of the gaps studied were formed or affected by Typhoon Milenyo, which hit the study site in September 2006. The most frequent mode of gap maker death was snap-off, whereas uprooting was relatively less important. The most frequent gap maker was balobo (Diplodiscus paniculatus) followed by magabuyo (Celtis luzonica) and katmon (Dillenia philippinensis). In contrast, the most frequent gap filler was magabuyo (C. luzonica). At the sapling layer, the most important species was magabuyo (C. luzonica), but there was a high proportion of lianas and palms. Most of the gaps had leaf area index (LAI) values between 3 and 5. A clear trend of a decrease in gap size and an increase in LAI was observed for 2 years from 2007 to 2009. New seedlings emerged very abundantly during the same time period. The rapid changes in the gaps were partially due to the excellent capability of tropical trees to resprout after the crown or stem was damaged by the typhoon. This study on gap dynamics may contribute to a better understanding of the natural regeneration process of trees in tropical rainforests.

• Journal of Forest and Environmental Science
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• 제10권1호
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• pp.1-7
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• 1994

브라질 연방지역(聯邦地域)을 흐르는 Sao Bartolomeu 강 유역(流域)에 자생하는 삼림의 천연경신(天然更新)에 대한 정보를 얻기 위하여 삼림조사(森林調査)가 실시되었다. 1ha 삼림면적내의 임분천이(林分遷移) 구성(構成)을 조사하기 위해 $100m^2$의 삼림조사구(森林調査區)가 설정되었다. 수고(樹高)에 따라 분류된 4개의 등급 각각에 총 4262본(55개 수종(樹種))이 분포되어 있는 것으로 조사되었다. 각 등급의 식물사회학적(植物社會學的) 가치(價値)는 3.3, 2.4, 2.0, 2.3등으로 나타났으며 이것을 통해 각 수종의 식물사회학적 위치를 확인할 수 있었다. 천연경신림분(天然更新林分)의 상대도(相對度) 및 중요치(重要値) 계산의 결과 다음과 같은 10대(大) 수종(樹種)이 가장 중요한 것으로 나타났다. 즉, Cheiloclinium cognatum A.C. Smith, Piptadenia communis Benth., Faramea cyanea M. Arg., Xylopia sericea St. Hil., Copaifera lansdorfii Desf., Cupania vernalis Camb., Matayba guianensis Aublet, Virola sebifera Aublet, Ocotea densiflora Meissn 그리고 Didimopanax morototoni (Aublet) Dcne et Pl.

• KIEAE Journal
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• 제17권3호
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• pp.23-34
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• 2017

Purpose: The purpose of this study is to explore the relationship between suburban waterfront und urban regeneration strategies. Specifically, This paper investigates how urban design strategies for suburban waterfront has been conceptualized and realized in a case-based research study of the regeneration of suburban waterfront in Berlin, Germany. Since Germany's reunification, Berlin was faced a wide variety of challenges and has been transformed into a new capital city. First of all, Wasserstadt Berlin-Oberhavel was a key development task for the urban regeneration in Berlin. The Wasserstadt Berlin-Oberhavel project with over 207 hectares will provide new residential urban areas, office spaces, educational facilities and cultural facilities. In details, 3,640 apartments with 12,700 units and around 4,800 jobs will be created. Method: The study consists of five sections. The first and second section are divided into two stages:"waterfront definition in urban design" and "urban design strategy in waterfront". The third section explores the waterfront development process of Wasserstadt Berlin-Oberhavel. The fourth section aims to investigate the strategies for urban regeneration as well as waterfront development. Finally, the fifth provides some of the key policy challenges for Urban Regeneration in suburban waterfront area. Result: The results showed that urban regeneration strategies in suburban waterfront have a substantial impact on all two dimensions: relationship between waterfront and urban context, relationship between waterfront and natural environment.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2002년도 춘계학술대회
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• pp.172-172
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• 2002

• Journal of Plant Biotechnology
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• 제30권3호
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• pp.245-249
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• 2003

This study was carried out to establish a regeneration system from leaf explant of purple sweetpotato(Ipomoea batatas L.) The optimal concentrations of plant growth regulators for callus induction and shoot formation were determined. The optimal combination for callus formation was 1$\mu$M 2,4-D 5$\mu$M BM, and highest yield of embryogenic calli were observed on Murashige and Skoog basal medium containing 0.5$\mu$M 2,4-D under light condition after 4weeks of culture. Embryogenec callus was subcultured on medium supplemented with 5$\mu$M ABA for 4 days. Subsequently, regeneration of adventitious shoots occurred when these embryogenic calli were transferred onto medium with 3∼6$\mu$M gibberellic acid. Regenerated shoots were developed into normal plantlets.

• BMB Reports
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• 제49권1호
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• pp.26-36
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• 2016

Emerging trends for cardiac tissue engineering are focused on increasing the biocompatibility and tissue regeneration ability of artificial heart tissue by incorporating various cell sources and bioactive molecules. Although primary cardiomyocytes can be successfully implanted, clinical applications are restricted due to their low survival rates and poor proliferation. To develop successful cardiovascular tissue regeneration systems, new technologies must be introduced to improve myocardial regeneration. Electrospinning is a simple, versatile technique for fabricating nanofibers. Here, we discuss various biodegradable polymers (natural, synthetic, and combinatorial polymers) that can be used for fiber fabrication. We also describe a series of fiber modification methods that can increase cell survival, proliferation, and migration and provide supporting mechanical properties by mimicking micro-environment structures, such as the extracellular matrix (ECM). In addition, the applications and types of nanofiber-based scaffolds for myocardial regeneration are described. Finally, fusion research methods combined with stem cells and scaffolds to improve biocompatibility are discussed. [BMB Reports 2016; 49(1): 26-36]

• 한국토양비료학회지
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• 제50권3호
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• pp.179-186
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• 2017

This study was conducted to identify characteristics of domestic pine forest soils and to elucidate major soil influencing factors for natural regeneration. We analyzed the physico-chemical characteristics of the soil samples collected from 23 pine forests and confirmed the similar results with the forest soil characteristics. Soil pH, organic matter content, total nitrogen, exchangeable Ca, silt content, and exchangeable Al were selected as the major soil factors among the exposed soils through 10 days of pine seedlings exposure and cultivation experiments and statistical analysis. Multiple regression analysis showed that soil pH had a positive effect on specific root length (SRL) of red pine seedlings and exchangeable Al was a significant factor affecting negative change in SRL. Taken together, the reduction of exchangeable Al by soil pH adjustment would be helpful for natural regeneration by restoring the forest and improving the fine root and root integrity of pine seedlings. Therefore, soil pH and exchangeable Al could be recommended as a major soil factor to be carefully considered in the monitoring and management of soil in pine forests that need to be renewed in the future.

• 대한토목학회논문집
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• 제38권5호
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• pp.761-769
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• 2018

최근 안전에 대한 관심이 높아지고 있으나, 도시재생 사업에서 안전에 대한 고려는 충분히 이루어지지 못하고 있다. 본 연구에서는 부산시 동구와 남구를 대상으로 재해와 생활안전 지표들을 선택적으로 적용하여 안전 취약성을 분석하고, 주민의 도시재생 및 주거지 안전에 대한 인식을 조사 분석하였다. 분석 결과, 동구 범일2, 5동과 남구 감만동이 안전에 가장 취약한 것으로 드러났다. 도시재생사업에 대한 주민들의 인지도는 비교적 높았으나 안전성 개선효과에 대해서는 부정적이었다. 최우선적으로 개선되어야 할 영역으로는 노후건물관련사고를 꼽았으며, 자연재해보다는 생활안전사고에 더욱 취약하다고 평가하였다. 향후의 도시재생사업에서는 이러한 연구결과와 지역별로 취약한 재해 사고유형이 필수적으로 반영되어야 할 것이다.

• Rapid Communication in Photoscience
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• 제2권2호
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• pp.42-45
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• 2013

Natural photosynthesis utilizes solar energy to convert carbon dioxide and water to energy-rich carbohydrates. Substantial use of sunlight to meet world energy demands requires energy storage in useful fuels via chemical bonds because sunlight is intermittent. Artificial photosynthesis research focuses the fundamental natural process to design solar energy conversion systems. Nicotinamide adenine dinucleotide ($NAD^+$) and $NADP^+$ are ubiquitous as electron transporters in biological systems. Enzymatic, chemical, and electrochemical methods have been reported for NADH regeneration. As photochemical systems, visible light-driven catalytic activity of NADH regeneration was carried out using platinum nanoparticles, molecular rhodium and cobalt complexes in the presence of triethanolamine as a sacrificial electron donor. Pt nanoparticles showed photochemical NADH regeneration activity without additional visible light collector molecules, demonstrating that both photoactivating and catalytic activities exist together in Pt nanoparticles. The NADH regeneration of the Pt nanoparticle system was not interfered with the reduction of $O_2$. Molecular cobalt complexes containing dimethylglyoxime ligands also transfer their hydrides to $NAD^+$ with photoactivation of eosin Y in the presence of TEOA. In this photocatalytic reaction, the $NAD^+$ reduction process competed with a proton reduction.