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Review of the developmental trend of implant surface modification using organic biomaterials (생체활성 유기물로 표면이 개질된 임플란트 개발 추이 분석 연구)

  • Hwang, Sung-Taek;Han, In-Ho;Huh, Jung-Bo;Kang, Jeong-Kyung;Ryu, Jae-Jun
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.3
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    • pp.254-262
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    • 2011
  • Purpose: This study aims to evaluate and prospect for current research trend and developmental perspectives via analyzing recent biomaterial coated-implants study. Materials and methods: To investigate each subject respectively, several biomaterials that are using for implant surface coating were set as 'keywords'. By these keywords, major research groups in each subject were chosen, and research trend of them was analyzed. Trend of In vivo studies that examined selected biomaterials were analyzed to evaluate commercial potential. Results: The collagen research accounted for 40% of total implant study, which was the highest, and fibronectin, BMPs (bone morphogenetic proteins) and RGD (Arg-Gly-Asp) peptides followed, which were ranked in descending order. Furthermore, figures of all four research subjects were also increased with time, especially a sharp increase in RGD research. According to the results of major research group, collagen that was combined with other organic and inorganic biomaterials was mostly examined, rather than using collagen only. Major research groups investigating BMPs mostly focused on rhBMP-2. In animal studies, collagen was used as resorbable membrane in guided bone regeneration (GBR) or drug carrier, while BMPs were used with bone graft materials or coating material for titanium implant surface. Conclusion: There is not consistency of results even in identical subjects research field. Many studies are ongoing to optimize combination between mechanical surface treatment and biomaterials such as extracellular matrix component and growth factors.

The Analysis of a Cerrobend Compensator and a Electronic Compensator Designed by a Radiation Treatment Planning System (방사선치료계획장치로 설계된 Cerrobend 선량보상체와 전자 선량보상체의 제작 및 특성 분석)

  • Nah Byung-Sik;Chung Woong-Ki;Ahn Sung-Ja;Nam Taek-keun;Yoon Mi-Sun;Song Ju-Young
    • Progress in Medical Physics
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    • v.16 no.2
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    • pp.82-88
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    • 2005
  • In this study, the physical compensator made with the high density material, Cerrobend, and the electronic compensator realized by the movement of a dynamic multileaf collimator were analyzed in order to verify the properness of a design function in the commercial RTP (radiation treatment planning) system, Eclipse. The CT images of a phantom composed of the regions of five different thickness were acquired and the proper compensator which can make homogeneous dose distribution at the reference depth was designed in the RTP. The frame for the casting of Cerrobend compensator was made with a computerized automatic styrofoam cutting device and the Millennium MLC-120 was used for the electronic compensator. All the dose values and isodose distributions were measured with a radiographic EDR2 film. The deviation of a dose distribution was $\pm0.99 cGy\;and\;\pm1.82cGy$ in each case of a Cerrobend compensator and a electronic compensator compared with a $\pm13.93 cGy$ deviation in an open beam condition. Which showed the proper function of the designed compensators in the view point of a homogeneous dose distribution. When the absolute dose value was analyzed, the Cerrobend compensator showed a $+3.83\%$ error and the electronic compensator showed a $-4.37\%$ error in comparison with a dose value which was calculated in the RTP. These errors can be admtted as an reasonable results that approve the accuracy of the compensator design in the RTP considering the error in the process of the manufacturing of the Cerrobend compensator and the limitation of a film in the absolute dosimetry.

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Effect of Miscanthus Biomass Application on Upland Soil Physicochemical Properties and Crops Growth (억새 바이오매스 시용이 밭토양 이화학성과 작물 생육에 미치는 영향)

  • Kang, Yong Ku;Moon, Youn Ho;Kwon, Da Eun;Lee, Ji Eun;Kim, Kwang Soo;Cha, Young Lok
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.1
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    • pp.72-78
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    • 2020
  • In this study, miscanthus with C/N ratio of 224 were applied to the soil and treated with 0 (control), 10 tons and 20 tons·ha-1 to improve the soil and promote crop growth. As a result, soil organic matter content increased from 11.0 g·kg-1 before the test to 16.3 after 3 years. Soil cation exchangeable capacity increased to 15.3 cmolc·kg-1 after 3 years. In the sweet sorghum, stem was the most thickest at 20 tons·ha-1 application of miscanthus and the highest juice amount per plant was 60 ml. The yield index multiplied by the soluble solids content of juice and juice amount was the highest at 1,913 for 10 tons application and 1,851, 1,839 for 20 tons, control respectively. Number of sweetpotato storage root were 2,9 in 20-tons application plot, the same as control, and 10-tons application plot was 3.6, the most. Two-year average yields of 20 tons plot and control were low at 2,579 kg/10a and 2,708 respectively, and 10 tons plot was the highest at 3,289. For onions, the biomass application did not effect the yield. but onion plant and leaf length were longer in 20 tons plot than in control or 10 tons. The yield of garlic was 2,630~2,901 kg/10a and there was no effect of miscanthus application. Plot of 10 tons application were the longest in plant and leaf length, and the number of scale was 8.2-8.3 per in bulb, and 8.9 tons·ha-1 in control. Therefore, it was confirmed the possibility that miscanthus biomass application of about 10 tons·ha-1 could improve the soil condition and promote crops growth and yield.