979 resultados para Middleton, Conyers, 1683-1750.


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本发明为一种具有生物活性的纯化多肽及其制备的用于促进动物神经细胞生长、发育以及抑制其凋亡的药物,含有下列氨基酸序列(SEQ IDNO:1),由适量的具有生物活性的纯化多肽和制药上可接受的赋形剂和稀释剂组成。主要用于促进动物神经细胞生长、发育,效果良好。

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This paper explores supply network integration in complex product service systems involving close collaboration between primes. Four case study networks are studied (aerospace, naval, power and telecoms), each involving equipment manufacture and service provision. Factors that support network integration, identified from the literature and refined in the in-depth pilot case, were used to explore which processes support integration of the extended enterprise. Results suggests that a select set of processes support integration of the extended enterprise and that the absence of a shared view on these critical enabling processes results from contextual complexity of the network rather than from competing commercial interests. Copyright © 2011 Inderscience Enterprises Ltd.

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In this work, speed of sound in 2 phase mixture has been explored using CFD-DEM (Computational Fluid Dynamcis - Discrete Element Modelling). In this method volume averaged Navier Stokes, continuity and energy equations are solved for fluid. Particles are simulated as individual entities; their behaviour is captured by Newton's laws of motion and classical contact mechanics. Particle-fluid interaction is captured using drag laws given in literature.The speed of sound in a medium depends on physical properties. It has been found experimentally that speed of sound drops significantly in 2 phase mixture of fluidised particles because of its increased density relative to gas while maintaining its compressibility. Due to the high rate of heat transfer within 2 phase medium as given in Roy et al. (1990), it has been assumed that the fluidised gas-particle medium is isothermal.The similar phenomenon has been tried to be captured using CFD-DEM numerical simulation. The disturbance is introduced and fundamental frequency in the medium is noted to measure the speed of sound for e.g. organ pipe. It has been found that speed of sound is in agreement with the relationship given in Roy et al. (1990). Their assumption that the system is isothermal also appears to be valid.

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Eleven polymorphic microsatellite loci were characterized for the endangered conifer Taxus yunnanensis. Eight loci were isolated through SSR-anchored PCR, one locus was developed by cross-species amplification tests, while the last two loci were obtained

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2003年3月-2004年3月对无量山大寨子3群西黑冠长臂猿的二重唱的时间特征进行了监测。于2007年3月和2008年3月利用Sony TC-D5Pro2录音机、Sony C-76指向性话筒和Sony录音磁带对其二重唱进行了录音,对录音效果最好的5个声音用Signal/RTS4.0软件进行声谱分析。对无量山西黑冠长臂猿二重唱的声谱结构和时间特征的研究结果表明,雄性西黑冠长臂猿的声音由起始音节、简单的重复音节和调节音节组成。根据频率变化的强度,可以将调节音节分为弱调节音节和强调节音节。强调节音节的特征是第二个音节具有非常明显的频率变化,有时第三个音节有类似变化,变频时的最高频率可达到5828Hz。雌性长臂猿一般只会发出一种类型的声音,即固定而刻板的激动鸣叫。根据激动鸣叫是否完整可以分为成功的激动鸣叫和失败的激动鸣叫。典型的西黑冠长臂猿二重唱通常由成年雄性发起,并占主导地位,且一般由雄性结束。雌性激动鸣叫结束后,雄性马上发出调节音节与之配合,雄性调节音节与雌性激动鸣叫的时间间隔平均为2.7s。平均每个群体的鸣叫频次为53%。如果发生鸣叫,一个群体平均每天鸣叫1.09次。91.5%的鸣叫发生在日出前0.5h至日出后...

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In current practice the strength evaluation of a bridge system is typically based on firstly using elastic analysis to determine the distribution of load effects in the elements and then checking the ultimate section capacity of those elements. Ductility of the components in most bridge structures permits local yield and subsequent redistribution of the applied loads from the most heavily loaded elements. As a result a bridge can continue to carry additional loading even after one member has yielded, which has conventionally been adopted as the "failure criterion" in bridge strength evaluation. This means that a bridge with inherent redundancy has additional reserves of strength such that the failure of one element does not result in the failure of the complete system. For these bridges warning signs will show up and measures can be undertaken before the ultimate collapse is happening. This paper proposes a rational methodology for calculating the ultimate system strength and including in bridge evaluation the warning level due to redundancy. © 2004 Taylor & Francis Group, London.

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锥虫(trypanosome)是最早在鱼类血液中发现、随后在几乎所有的脊椎动物血液里都有发现的原生动物寄生虫。它主要通过水蛭和吸血昆虫传播,使宿主受到不同程度的危害。为了较全面地了解锥虫系统发育的研究进展,本文综述了国内外有关锥虫系统发育研究的四个方面的内容锥虫的起源(介绍了锥虫起源于脊椎动物和起源于无脊椎动物的两种不同观点);锥虫的系统发育方式(单系发育);锥虫的进化是否与寄主存在协同性及进化史上分歧时间的差异性;目前研究中存在的问题。

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An engineer assessing the load-carrying capacity of an existing reinforced concrete slab is likely to use elastic analysis to check the load at which the structure might be expected to fail in flexure or in shear. In practice, many reinforced concrete slabs are highly ductile in flexure, so an elastic analysis greatly underestimates the loads at which they fail in this mode. The use of conservative elastic analysis has led engineers to incorrectly condemn many slabs and therefore to specify unnecessary and wasteful flexural strengthening or replacement. The lower bound theorem is based on the same principles as the upper bound theorem used in yield line analysis, but any solution that rigorously satisfies the lower bound theorem is guaranteed to be a safe underestimate of the collapse load. Jackson presented a rigorous lower bound method that obtains very accurate results for complex real slabs.

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通过回转器模拟微重力刺激实验 ,以盐生杜氏藻为试验材料 ,发现在微重力刺激下 ,盐生杜氏藻细胞及其生理生化特性发生了一系列的变化 .具体表现为甘油含量增加 ;H+分泌速率加快 ;膜磷脂与膜蛋白比率下降 ;质膜 (PM )H+ ATPase活性升高等 .这些变化表明 ,微重力环境对藻类来说是一个耗能胁迫环境 .微重力对藻细胞代谢特性的影响可能是通过次级的水分胁迫而产生的

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<正> 一.引言沙壳纤毛虫亚目(Tindnnoinea)是一类披有外壳的浮游寡毛类(Oligotricha)原生动物,种类极为繁多。根据郭甫德与肯培尔(Kofoid & Campbell,1929)的统计,此类动物在文献上的记录已超出了1750个种、亚种、变种或型的描述。又据羽田(Hada,1939)的报告,淡水裹的沙壳纤毛虫主要是包括筒壳虫(Tintinnidium)和似铃壳虫(Tintinnopsis)两属,而这两属在科学上有过记录的淡水种类,还祇有10种左右。由此可见,海洋与淡水里的沙壳纤毛虫的种类

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An MPhil programme, delivered by the Engineering Department at the University of Cambridge, claims to be excellent at preparing graduates for manufacturing industry careers. The course uses a combination of different educational experiences, including industry-based assignments, industrial visits and practical exercises. This research explores how problem solving skills are developed during the first module, Induction, which is designed to enable students to undertake their first industrial assignment. From the literature, four conditions necessary for skill development were identified: Provision of a skill description, making explicit key components A number of different experiences with a range of contextual variables A teaching process which includes regular feedback and student reflection Students motivated to learn. These were used to construct a skill development framework (SDF). Using a case study research design, multiple types of evidence were collected to test for the above conditions using both classroom observation and questionnaire methods. The results confirmed the presence of the SDF conditions at different levels, with reflection aspects considered the weakest. Conflicting results were obtained regarding the students' self-awareness of skill levels. A plausible explanation is a change in the students' frame of reference. This initial study set out to develop a better understanding of the process of skill development. Whilst the SDF appears reasonable, there is a need for further work in three broad areas of defining skills, assessing skills and developing reflection skills.

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There has recently been considerable research published on the applicability of monitoring systems for improving civil infrastructure management decisions. Less research has been published on the challenges in interpreting the collected data to provide useful information for engineering decision makers. This paper describes some installed monitoring systems on the Hammersmith Flyover, a major bridge located in central London (United Kingdom). The original goals of the deployments were to evaluate the performance of systems for monitoring prestressing tendon wire breaks and to assess the performance of the bearings supporting the bridge piers because visual inspections had indicated evidence of deterioration in both. This paper aims to show that value can be derived from detailed analysis of measurements from a number of different sensors, including acoustic emission monitors, strain, temperature and displacement gauges. Two structural monitoring systems are described, a wired system installed by a commercial contractor on behalf of the client and a research wireless deployment installed by the University of Cambridge. Careful interpretation of the displacement and temperature gauge data enabled bearings that were not functioning as designed to be identified. The acoustic emission monitoring indicated locations at which rapid deterioration was likely to be occurring; however, it was not possible to verify these results using any of the other sensors installed and hence the only method for confirming these results was by visual inspection. Recommendations for future bridge monitoring projects are made in light of the lessons learned from this monitoring case study. © 2014 This work is made available under the terms of the Creative Commons Attribution 4.0 International license,.

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Morphology of self-assembled GeSi quantum dot grown on Si(113) by Si molecular beam epitaxy has been studied by transmission electron microscopy and atomic force microscopy. Photoluminescence from the as-grown sample and annealed sample was studied. The results were analyzed and explained.