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101.
Sumathy Arumuganathar Scott Irvine Jean R. McEwan Suwan N. Jayasinghe 《应用聚合物科学杂志》2008,107(2):1215-1225
In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
102.
A. Mounir EL Sayed A. Yamauchi N. A. Darwish A. A. Abd EL‐Mageed S. F. Halim 《应用聚合物科学杂志》2008,109(5):2988-2993
The charged mosaic polymer membrane (CMM) without reinforcement and the composite charged mosaic polymer membrane (CCMM) with reinforcement were investigated in terms of salt and water transport (permeability). The composite charged mosaic polymer membrane (CCMM) with reinforcement showed a unique transport behavior such as preferential material transport Lp and ω. Water permeability coefficient, Lp and salt permeability coefficient, ω were estimated by taking account of active layer thickness of composite polymer gel. The Lp and ω values of CCMM with reinforcement were larger than those of CMM without reinforcement. On the other hand, the reflection coefficient of CCMM, σ, showed negative value, which suggested preferential material transport to solvent transport. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
103.
Effect of Li+ ions on structure,properties, and actuation of cellulose electro‐active paper actuator
We have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
104.
介绍光电被动感应控制开关模块工作原理,研究开发了一种基于被动感应控制原理的自动冲水控制装置,总结比较了主动感应控制与被动感应控制的优缺点及其应用特点。 相似文献
105.
Hughes Rosemary B.; Nosek Margaret A.; Howland Carol A.; Groff Janet Y.; Mullen Patricia Dolan 《Canadian Metallurgical Quarterly》2003,48(3):182
Objective: To pilot test a health promotion intervention for women with physical disabilities. Design: Pre- and postintervention questionnaires. Participants: Two groups of women with physical disabilities (n=15). Intervention: Seven-session weekly workshop intervention grounded primarily in social-cognitive theory. Setting: Disability and rehabilitation settings. Main Outcome Measures: Indicators of health status. Results: Statistically significant positive changes between pre- and postintervention scores on measures of self-efficacy for dietary behaviors, medical decision making, social interaction, physical functioning, impact of physical limitation on role activities, and vitality. Conclusion: Women with disabilities who participate in this health promotion intervention may exhibit improvements on indicators of health status. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Mustafa Ayhan Erkan Topal 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2005,20(1):81-87
Tunneling projects have their uniqueness in terms of engineering problems. The expertise gained from analyzing these projects establishes a sound basis for future application. This paper conveys experiences gained during the construction and support of the design of the Dicle–Kralkizi water tunnel, Turkey. Tunnel stability problems including overbreaks and surface subsidence are evaluated. An analysis of the breakdowns, factors controlling advance rate and the overall performance of tunnel are covered. The accumulated information presented here is believed to be useful and reliable for a successful tunnel excavation in similar formations. 相似文献
107.
云台山隧道进口黄土段施工技术 总被引:2,自引:2,他引:0
从防排水、边仰坡支护、洞口加固、洞内超前支护、钢拱架锚喷联合支护等方面详细介绍了云台山隧道进口黄土段的施工技术,总结了该隧道的施工效果,强调了黄土隧道施工中防排水超前支护预注浆、施工监控的作用,积累了隧道施工经验. 相似文献
108.
论文主要介绍了电机的调速方法、变频器的工作原理以及日本FRNIC500G7型变频器在桥式抓斗吊车上的应用,并分析了使用绕线式电机调速与鼠笼式电机变频调速之间的优缺点。 相似文献
109.
经过对支座转角组合进行的分析,在研究柔性高墩墩顶转角位移计算方法的基础上,提出了更加严密的支座转角验算修正公式,得出修正后的转角验算公式易于应用的结论,对于保证板式橡胶支座在使用过程中不脱空有重要的意义。 相似文献
110.
This study examined the interrelationships among economic pressure, maternal depression, social support, and marital conflict in a sample of 239 mothers in Romania. Data were collected through a school-based survey. Findings indicated that higher levels of economic pressure were associated with higher levels of marital conflict. Economic pressure was also associated with higher marital conflict indirectly through increased maternal depression and lowered social support. The present results were similar to those obtained in studies conducted among U.S. samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献