• Title/Summary/Keyword: natural regeneration

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A Study on Electricity Generation of Marine Sediment Cells (해양 퇴적토전지의 발전 특성에 대한 연구)

  • Lee, Eun-Mi;Kwon, Sung-Hyun;Rhee, In-Hyoung;Park, Byung-Gi;Cho, Dae-Chul
    • Journal of Environmental Science International
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    • v.20 no.5
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    • pp.647-653
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    • 2011
  • Sediment cell is renewable energy which produces electric energy using immanent ingredients or reducing power of marine sediment as natural resources. Also the cell has an advantage that environmental pollution can be reduced through conversion of organic and inorganic contaminants into inert matter with generation of the energy. In this paper, we compared characteristics of electricity generation of the two different sediment cells, and investigated the regeneration effect of the sediment cells with manipulation of the sediment such as mixing and re-positioning. The results showed that 14.1 $W/m^2$ of power was obtained with the aluminum electrode, and the mixing of the sediment could increase the power by 4 $W/m^2$ compared to the control. Also, mixing the sediment has kept electricity for 4 weeks at a relatively constant level, which implied 'fuel regeneration effect'. Meanwhile, the sediment cell was proved to be effective in reduction of COD, which was up to 28.6%.

Comparative Evaluation of Fibrin for Bone Regeneration in Critical Size Calvarial Defects

  • Song, Gin-Ah;Kim, Soung Min;Woo, Kyung Mi
    • International Journal of Oral Biology
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    • v.39 no.3
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    • pp.153-157
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    • 2014
  • Natural biopolymers such as collagen and fibrin have been widely used in bone regenerative applications. Despite the frequent use, their comparative biological propertiesis are largely unknown. In a previous study, we found the superiority of fibrin to collagen in the adsorption of serum proteins and the proliferation and differentiation of cultured osteoblasts. In this study, we used an in vivo model to evaluate how effectively fibrin supports bone regeneration, as compared with collagen. Collagen and fibrin were placed in critical size defects made on rat calvarial bones. Compared with collagen, fibrin supported substantially more new bone tissue formation, which was confirmed by micro-CT measurement and histological analyses. The cells in the regenerative tissues of the fibrin-filled defects were immunostained strongly for Runx2, while collagen-placed defects were stained weakly. These in vivo results demonstrate that fibrin is superior to collagen in supporting bone regeneration.

Varietal Difference Based on Efficiency of Rice Anther Floating Culture

  • Kang, Hyeon-Jung;Lee, Seong-Yeob;Kim, Hyun-Soon;Lee, Jae-Gil
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.5
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    • pp.335-340
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    • 2002
  • To evaluate the efficiency of anther floating culture according to the maturing group, the varietal difference and classification of fifty varieties was conducted in N6 liquid medium containing 1mg $l^{-1}$ NAA, 0.25 mg $l^{-1}$ kinetin. The efficiency of callus induction was widely ranged from 0 to 113.4%, but the mean callus induction was not significantly different among maturing groups. The efficiency of anther floating culture showed the highest variation in early-maturing group among three maturing groups. The varieties with the best callus induction were Sambaegbyeo and Jinbuolbyeo, while the recalcitrant variety was Obongbyeo in early-maturing group. The efficiency of plant regeneration showed the highest trends in late-maturing group among three maturing groups. The fifty varieties were classified into three groups (distance=0.78) by cluster analysis based on the callus formation and plant regeneration. Group including only two varieties, Shinunbongbyeo and Sambaegbyeo had the excellent androgenic efficiency, and the medium efficiency of Group was included thirty-six varieties. Whereas twelve varieties, including three Tongil varieties were fell into the bad efficiency of Group. Especially, Tongil varieties containing Japonica rice, Obongbyeo were the recalcitrant genotypes for the anther floating culture.

High Frequency Plant Regeneration from the Cultures of Cotyledon Explants of Perilla (Perilla frutescens L.) (들깨의 자엽절편배양을 통한 고효율 식물체 재분화)

  • Kim, Kyung-Min;Lee, Hyeon-Suk
    • Journal of Plant Biotechnology
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    • v.34 no.1
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    • pp.69-73
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    • 2007
  • A reliable and effective tissue culture system was established for Perilla frutescens (perilla) using different cultivar, explant source, and growth regulator composition in medium. MS medium supplemented with 2.0 mg/L BA and 0.1 mg/L NAA was maximum at shoot induction. Cotyledon explants formed more shoots than hypocotyl explants. The frequency of plant regeneration through organogenesis was higher (22.8%) than that (6.1%) of somatic embryogenesis. Five genotypes of perilla were screened for the feasibility of shoot regeneration, cotyledon explant of 'Manbaek' showed the highest shoot induction at a frequency of 27.3% among the tested cultivars.

Chair-side surface treatment method for inducing hydrophilicity in titanium dental implant (치과용 티타늄 임플란트의 골융합 증진을 위한 체어사이드 친수성 표면처리방법)

  • Lee, Jung-Hwan;Jun, Soo-Kyung;Lee, Hae-Hyoung
    • The Journal of the Korean dental association
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    • v.54 no.12
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    • pp.985-995
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    • 2016
  • Titanium (Ti) has been widely used for dental implant due to great biocompatibility and bonding ability against natural alveolar bone. A lot of titanium surface modification has been introduced in dentistry and, among them, methods to introduce micro/nano-roughened surface were considered as clinically approved strategy for accelerating osseointegration of Ti dental implant. To have synergetic effect with topography oriented favors in cell attachment, chair-side surface treatment with reproducibility of micro/nano-topography is introduced as next strategy to further enhance cellular functionalities. Extensive research has been investigated to study the potential of micro/nano-topography preserved chair-side surface treatment for Ti dental implant. This review will discuss ultraviolet, low level of laser therapy and non-thermal atmospheric pressure plasma on Ti dental implant with micro/nano-topography as next generation of surface treatment due to its abilities to induce super-hydrophilicity or biofunctionality without change of topographical cues.

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An Analysis of Community Asset Types and Components for a Development of Community Asset Evaluation System (커뮤니티 자산 평가 체계 개발을 위한 커뮤니티 자산 유형 및 구성요소 분석)

  • Yim, Soon Jeong;Lee, Hyo Won
    • Journal of the Korean housing association
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    • v.27 no.3
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    • pp.47-58
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    • 2016
  • The new paradigm of urban regeneration, would promote the comprehensive communal view. Therefore, the community role has become an important and necessary for regeneration of communities. It is necessary for urban regeneration which should be matched with the regional characteristics, to develop an evaluation framework that can objectively and accurately diagnose the status of community; so it can be an integrated prescription. A new alternative, asset-based approach may be an alternative to build the community based on opportunities and strengths, which focuses on community inside and things that community have. In this study, a community asset is defined as the tangible and intangible components in the community. A community asset evaluation system is developed through the content analysis related to previous studies of several researchers who investigated the asset-based approaches. Community assets are classified into seven types: human, social, cultural, natural, physical, economic, and political property. Each type is classified into components and establish as a framework with 3 levels in order to set the indicators which can be measured concretely.

Performance of Air Source Heat Pump with a Fiber Belt Heat Regeneration System (섬유벨트 열재생 시스템을 부착한 공기 열원 열펌프의 난방 성능 특성)

  • 유영선;장진택;김영중;강금춘;윤진하;이건중
    • Journal of Biosystems Engineering
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    • v.25 no.5
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    • pp.385-390
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    • 2000
  • The heat pump is one of heating and cooling systems driven by electricity using natural energy as a heat source. The heat pump system was mainly adopted to a cooling system or a refrigeration system. In regions with a large amount of electricity, it is used as a heating system or a heating and cooling system of houses, buildings and agricultural facilities. During cold weather, air source heat pumps do not work well because of some technical problems, such as frosting on evaporator coil when outside air temperature is below -5$^{\circ}C$. In this research, the heat regenerative technology was employed to eliminate the frosting on evaporator coil and improve the COP of the heat pump system. This fiber belt heat regeneration system(FBHRS) has very simple structure consisting of a geared motor and a porous fiber belt passing through alternatively between cold and warm air duct. The laboratory test showed that the heat pump system with a FBHRS yielded an impressive COP higher than 3.5 at the outside air temperature of -7$^{\circ}C$ in heating mode.

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Plant Regeneration through Organogenesis from Callus of Camptotheca acuminata Decaisne (희수나무 캘러스로부터 기관분화에 의한 식물체 재분화)

  • Bae, Dae-Ho;Park, Whoa-Shig;Hwang, Sung-Jin;Hwang, Baik
    • Korean Journal of Medicinal Crop Science
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    • v.17 no.3
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    • pp.192-197
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    • 2009
  • Camptotheca acuminata, a native of South China is a well known natural source of monoterpene-indole alkaloid camptothecin(CPT), one of the most promising anti-tumoural compounds. This study was conducted to optimize plant growth regulators and culture conditions on plantlets regeneration through organogenesis from callus of Camptotheca acuminta. Callus were induced from various explants of in vitro germinated plantlets of C. acuminta using WPM medium containing 0.2 ㎎/L 2,4-D. Hypocotyl segments were exhibited higher embryogenic callus than the other explants. Shoot buds formation from embryogenic callus was affected by plant growth regulators, pre-treated dark condition and liquid culture. Organogenesis was optimal in WPM liquid medium containing 0.5 ㎎/L BA. The dark pre-treatment for 2 weeks before the solid culture was effective for organogenesis. The regenerated shoots were rooted in WPM medium with 0.2 ㎎/L NAA and successfully acclimated in green-house conditions.

Inhibition of Cancer Cell Migration by Compounds from Garlic Extracts (마늘추출물에 의한 암세포의 이동 저하)

  • Kim, Eun-Kyoung;Yun, Sung-Ji;Ha, Jung-Min;Jin, In-Hye;Kim, Young-Whan;Kim, Sun-Gun;Park, Da-Jung;Choi, Young-Whan;Yun, Sik;Kim, Chi-Dae;Bae, Sun-Sik
    • Journal of Life Science
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    • v.21 no.6
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    • pp.767-774
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    • 2011
  • Cell migration plays a fundamental role in cancer cell invasion and metastasis as well as in many physiological responses. Here, we screened four different sources of garlic - water extract of normal and black garlic, as well as dried normal and black garlic - for the identification of anti-invasive and anti-metastatic activity on cancer cells. Inhibition of cancer cell migration was observed in the hexane extract of dried-garlic. Inhibitory activity was further purified to near homogeneity by thin layer chromatography and named $\b{i}$nhibitor of $\b{c}$ancer $\b{m}$etastasis from garlic #27 (ICMG-27). ICMG-27 completely blocked insulin-like growth factor-1 (IGF-1)-induced OVCAR-3 cell migration at 6 ${\mu}g/ml$. ICMG-27 completely blocked IGF-1-induced OVCAR-3 and NIH-3T3 cell migration whereas IGF-1-induced mouse embryonic fibroblast (MEF) cell migration was not affected byICMG-27. ICMG-27 inhibited all the tested IGF-1-induced cancer cell migration such as OVCAR-3, SKOV-3, and MDA-MB-231 cells. Finally, ICMG-27 could inhibit IGF-1-, lysophosphatidic acid (LPA)-, sphingosine-1-phosphate (S1P)-, leukotriene B4 (LTB4)-, and angiotensin II (AngII)-induced OVCAR-3 cell migration. These results indicate that ICMG-27 inhibits cancer cell migration by blocking essential steps in many agonists-induced cancer cell migrations. Unveiling an anti-invasive mechanism of ICMG-27 on cancer cells will provide a basis for cancer therapy.

Biological Effects of bioactive glass and natural coral on periodontal ligament fibroblast-like cell behavior (생체유리와 천연산호 골이식재가 치주인대 섬유아세포 활성에 미치는 영향)

  • Shim, Sung-Kyu;Han, Soo-Boo
    • Journal of Periodontal and Implant Science
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    • v.29 no.1
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    • pp.173-192
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    • 1999
  • The purpose of this study was to evaluate the effects of bioactive glass and natural coral on the human periodontal ligament fibroblast(HPLF) behaviors during the regeneration process of peridontium. To determine the cellular events occuring in the presence of the particles of bioactive glass and natural coral, HPLF were isolated from healthy premolar teeth extracted for orthodontic treatment. Cells were cultured in ${\alpha}$MEM at 37$^{\circ}C$, 5% $CO_2$, 95% humidity incubator. Bioactive glass and natural coral were powdered, and each particles(<40${\mu}$m) were placed on the cultured cells at the concentration of 0.3mg/ml, and 1,0mg/ml for experimental group. In control group no particles were added. And each group was evaluated by examining the cell morphology under phase-contrast micrograph at 4 day and transmission electron micrograph(TEM) and scanning electron micrograph(SEM) at 14 day, alkaline phosphatase activity at 5 and 9 day, protain synthesis at 4 day, DNA synthesis at 1, 2, 3 and 4 day, cell proliferation at 1, 3, 5,7 and 9 day and the formation of bone nodule at 30 day after culturing all groups in mineralizing supplemented mediun, No significant changes in cell morphology by adding these two matirials were found under phase contrast microscopy and TEM. HPLF phagocytocized each particles suggesting that HPLF is involved in the process of resorbing each particles and that bioactive glass were more biocompatible than natural coral. The ALPase activity of bioactive glass 0.3 mg/ml was similar with control groups and all the rests of control groups were significantly low(P<0.01) indicating a transient dedifferentiation of HPLF in the presence of bioactive glass and natural coral particles. There were no significant differences of protein synthesis between all groups. The DNA synthesis in experimental groups were significantly lower than control groups at 1, 2 and 3 day (P<0.01) but became similar to control groups at 4 day. Between control groups, the DNA synthesis in bioactive glass O.3mglml group was significantly higher than other groups(P<0.01). Cell proliferation in natural coral 1.0mg/ml and bioactive glass 1.0mglml groups were significantly lower than control group at 3 day(P<0.05) and there were no differences at 5, 7, 9 day. There were more bone nodule formation in experimental groups than in control groups. In conclusion, these results indicated that bioactive glass and natural coral have some effects of a transient dedifferentiation on HPLF and regeneration of periodontal tissues, however any significant cytotoxic effect on HPLF by these two particles were not found.

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