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Development of City Transport System and Two-wheel Vehicles 总被引:1,自引:0,他引:1
Based on the study on the city transport systems of some typical cities worldwide, this paper put forward that each city transport system has its own development mode, which is influenced by the city development plan, economic development level, traveling vehicle composition etc.. When some problems occur, such as the congestions caused by contradiction between the road capacity and vehicle composition, the city transport system may come into temporary maturity period. If the improvement for road system is limited meanwhile, optimized structure of vehicle composition should be an effective solution in this case. With the development of economy-internationalization, the development speed of city transport modernization is rapid. When traveling easiness is conflicting with efficiency, the advantages of public transport system become more obvious. Correspondingly, the superiority of two-wheel vehicles will reappear. Though the important function of two-wheel vehicles for alleviating city traffic problems i 相似文献
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Delaying the onset of Huntington's in mice 总被引:14,自引:0,他引:14
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This paper introduces a non-assembly manufacturing case with microstereolithography technology. The design and manufacturing process of a pneumatic thrust bearing is described, and a special tessellation method is developed to further improve the capability of the manufacturing system thus bigger products can also be easily manufactured. Implemented in a layer-by-layer fashion, stereolithography has been used for the rapid manufacturing of complex devices, and it avoids the expensive assembly process in the traditional manufacturing. This paper presents that microstereolithography can produce high-resolution products with intricate details, small openings, and smooth surfaces. The potential of the microstereolithograhy technique is explored for the rapid manufacturing of small and complex objects. 相似文献
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Yusa K Rashid ST Strick-Marchand H Varela I Liu PQ Paschon DE Miranda E Ordóñez A Hannan NR Rouhani FJ Darche S Alexander G Marciniak SJ Fusaki N Hasegawa M Holmes MC Di Santo JP Lomas DA Bradley A Vallier L 《Nature》2011,478(7369):391-394
Human induced pluripotent stem cells (iPSCs) represent a unique opportunity for regenerative medicine because they offer the prospect of generating unlimited quantities of cells for autologous transplantation, with potential application in treatments for a broad range of disorders. However, the use of human iPSCs in the context of genetically inherited human disease will require the correction of disease-causing mutations in a manner that is fully compatible with clinical applications. The methods currently available, such as homologous recombination, lack the necessary efficiency and also leave residual sequences in the targeted genome. Therefore, the development of new approaches to edit the mammalian genome is a prerequisite to delivering the clinical promise of human iPSCs. Here we show that a combination of zinc finger nucleases (ZFNs) and piggyBac technology in human iPSCs can achieve biallelic correction of a point mutation (Glu342Lys) in the α(1)-antitrypsin (A1AT, also known as SERPINA1) gene that is responsible for α(1)-antitrypsin deficiency. Genetic correction of human iPSCs restored the structure and function of A1AT in subsequently derived liver cells in vitro and in vivo. This approach is significantly more efficient than any other gene-targeting technology that is currently available and crucially prevents contamination of the host genome with residual non-human sequences. Our results provide the first proof of principle, to our knowledge, for the potential of combining human iPSCs with genetic correction to generate clinically relevant cells for autologous cell-based therapies. 相似文献
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在大型多项目交叉的建设工程施工电梯运输管理中,资源进度计划或随时间推进的资源分配,是一个复杂而需要解决的问题.结合建设工程仿真的发展,提出基于拍卖协议仿真模型的资源进度管理,建立基于Agent仿真的施工电梯运输管理系统.通过对该系统的应用,在复杂动态的环境下,可以获得资源进度计划,预测运输活动完成时间节点,计算完成活动消耗的成本,并且从运输活动工作包的逾期及其存储、电梯的闲置等多角度提高施工电梯运输管理的综合能力. 相似文献
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M. A. Hannan 《Cellular and molecular life sciences : CMLS》1972,28(10):1242-1243
Résumé Isolement de mutants résistants à lap-fluorophenylalanine et son analyse chezSchizophyllum communis.
This is a part of the Ph. D. work carried at the Department of Botany, Queen Mary College, London University, and the author wishes to express here grateful appreciation to ProfessorE. A. Bevan for his guidance in this study. 相似文献
This is a part of the Ph. D. work carried at the Department of Botany, Queen Mary College, London University, and the author wishes to express here grateful appreciation to ProfessorE. A. Bevan for his guidance in this study. 相似文献
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The tumour-suppressor gene Neurofibromatosis 1 (Nf1) encodes a Ras-specific GTPase activating protein (Ras-GAP). In addition to being involved in tumour formation, NF1 has been reported to cause learning defects in humans and Nf1 knockout mice. However, it remains to be determined whether the observed learning defect is secondary to abnormal development. The Drosophila NF1 protein is highly conserved, showing 60% identity of its 2,803 amino acids with human NF1 (ref. 12). Previous studies have suggested that Drosophila NF1 acts not only as a Ras-GAP but also as a possible regulator of the cAMP pathway that involves the rutabaga (rut)-encoded adenylyl cyclase. Because rut was isolated as a learning and short-term memory mutant, we have pursued the hypothesis that NF1 may affect learning through its control of the Rut-adenylyl cyclase/cAMP pathway. Here we show that NF1 affects learning and short-term memory independently of its developmental effects. We show that G-protein-activated adenylyl cyclase activity consists of NF1-independent and NF1-dependent components, and that the mechanism of the NF1-dependent activation of the Rut-adenylyl cyclase pathway is essential for mediating Drosophila learning and memory. 相似文献
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