摘要：Presenilins(PSs)are the catalytic core of γ-secretase ***,the mechanism of FAD-associated PS mutations in AD pathogenesis still remains *** we review the general biology and mechanism of γ-secretase and focus on the catalytic components–presenilins and their biological functions and contributions to the AD *** functions of presenilins are divided into γ-secretase dependent and γ-secretase independent *** γ-secretase dependent functions of presenilins are exemplified by the sequential cleavages in the processing of APP and Notch;the γ-secretase independent functions of presenilins include stabilizing β-catenin in Wnt signaling pathway,regulating calcium homeostasis and their interaction with synaptic transmission.

摘要：The distributed sensor is proven to be a powerful tool for civil structural and material process monitoring. Brillouin scattering in fiber can be used as point sensors or distributed sensors for measurement of temperature, strain, birefringence and vibration over centimeters （Brillouin grating length） for point sensor or the pulse length for the distributed sensor. Simultaneous strain and temperature measurement with a spatial resolution of 20 cm is demonstrated in a Panda fiber using Brillouin grating technique with the temperature accuracy and strain accuracy of 0.4 ℃ and 9 με. This technique can also be used for distributed birefringence measurement. For Brillouin optical time domain analysis （BOTDA）, we have developed a new technique to measure differential Brillouin gain instead of Brillouin gain itself. This technique allows high precision temperature and strain measurement over long sensing length with sub-meter spatial resolution： 50-cm spatial resolution for 50-km length, using return-to-zero coded optical pulses of BOTDA with the temperature resolution of 0.7 ℃, which is equivalent to strain accuracy of 12 με. For over 50-km sensing length, we proposed and demonstrated frequency-division-multiplexing （FDM） and time-division-multiplexing （TDM） based BOTDA technique for 75-km and 100-km sensing length without inline amplification within the sensing length. The spatial resolution of 2m （100km） and Brillouin frequency shift accuracy of 1.5 MHz have been obtained for TDM based BOTDA and 1-m resolution （75 km） with Brillouin frequency shift accuracy of 1 MHz using FDM based BOTDA. The civil structural health monitoring with BOTDA technique has been demonstrated.

摘要：The concept of“robust dynamics”describes the incorporation of mechanically interlocked molecules(MIMs)into metal-organic framework(MOF)materials such that large amplitude motions(e.g.,rotation or translation of a macrocycle)can occur inside the free volume pore of the *** aid in the preparation of such materials,reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF *** linkers were synthesized that have a T-shape,based on a triphenylene tetra-carboxylate strut,and their incorporation into Cu(II)-based MOFs was *** single-crystal structures of three new MOFs,UWCM-12(fof),β-UWCM-13(loz),UWCM-14(lil),with naked T-shaped linkers were determined;β-UWCM-13 is the first reported example of the loz topology.A fourth MOF,UWDM-14(lil)is analogous to UWCM-14(lil)but contains a[2]rotaxane ***-temperature,^(2)H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.

摘要：通用核心机技术不仅可增加所发展发动机的通用零件数,缩短研制周期,还可使所发展的各类发动机性能均较先进.不同流量的通用核心机可相应发展不同功率/推力范围的各类发动机,通用核心机的设计需考虑强度与气动性能的折衷,其部件应有宽广的高效与稳定工作范围,且通用前提下也允许核心机后续发展时有小的变动.文中最后讨论了某中小型通用核心机方案设计中涡轮级数和压气机形式的选择问题.

摘要：从环境兼容角度来设计应用于氧析出反应的电催化剂是否有效、耐用和廉价对能源转化过程至关重要.本文报告了一种快速制备低成本、原料丰富的金属催化剂制备方法.通过一步电化学沉积法在钛金属基材上制备了铁、镍、钴金属及其钴镍、钴铁二元金属纳米颗粒.采用场发射电子显微镜(FE-SEM)、能量散射X-射线能谱(EDX)、X-射线衍射光谱(XRD)、X-射线光电子能谱(XPS)和电化学技术对制备的不同纳米颗粒进行了表征.电化学结果显示,在合成的五种钛基金属纳米催化剂中,钛基上沉积钴金属纳米颗粒(Ti/Co)电极在0.l mol·L^(-1)氢氧化钾溶液中氧析出反应的电催化活性最好,0.70 V(相对于银/氯化银电极)的电流密度为10.0 mA·cm^(-2).经优化后Ti/Co电极的过电位(η)很小,当电流密度为10.0 mA·cm^(-2)时η为0.43 V,质量活性高达105.7 A·g^(-1),逆转频率(TOF)值为1.63×10^(-3) s^(-1),这些与当前最好的碳载铂(Pt/C)和氧化钌(RuO_2)电催化剂的性能相当.此外,通过计时电位技术对优化后Ti/Co电极的耐久性进行了测试,发现该电极在碱性溶液中氧析出反应的稳定性良好.本工作制备的钛金属基材上电化学沉积金属钴纳米颗粒具有高催化活性、高稳定性、原料来源丰富、廉价且易于大规模生产,在工业化水分解领域具有潜在的应用前景.

摘要：实施科学是一门研究方法的学科,旨在实践和政策中促进循证干预措施的系统实施,进而改善健康。尽管实施研究需要高质量的证据,但实施策略的随机试验往往存在较为严重的局限性。这些局限性包括存在偏倚风险、缺乏理论运用、缺乏描述实施策略标准术语、局限于实施结局以及不充分报告。本文旨在对实施策略随机试验的设计、实施和报告提供指导,以提升循证实施科学。由研究人员、卫生政策制订者和实践者组成的国际小组整合了构建随机试验方法的重要文献和实施科学的最新进展。本文为实施策略随机试验的主要内容提供指导,包括试验目的阐明、试验中人员招募和保留策略、随机设计的选择、实施科学理论和框架的使用、测量(结局指标)、样本量计算、伦理审查和试验报告。本文也关注了实施试验中需要特别重视或调整的主题。为了推进实施策略随机试验的严格开展和报告,我们建议将本指南作为研究人员、卫生保健和公共卫生政策制订者或实践者、研究资助者和期刊编辑的参考资料。

摘要：背景:对于与随机对照试验(randomized controlled trial,RCT)有关的学术会议论文或期刊中发表的文章来说,清楚、明了、信息量充足的摘要是十分重要的,因为读者经常仅仅根据报告的摘要对一个临床试验作出评价。为此,我们需要对"临床试验报告的统一标准(Consolidated Standards of Reporting Trials,CONSORT)声明"进行扩充,制定一个期刊与学术会议论文摘要中报告RCT的必备条目清单。今后在任何期刊发表的论文或学术会议论文摘要中,作者对RCT结果的报告都要包含这些内容。方法与结果:我们根据现有的质量评价工具和基于经验的证据总结出一个条目清单。运用三轮修正式德尔菲法(modified-Delphi process)进行条目筛选。邀请共计109人参与电子网络调查,反馈率为61%。调查结果于2007年1月在加拿大蒙特贝罗举行的CONSORT小组会议中公布,与会的26人中有临床试验实施人员、统计学家、流行病学家以及生物医学编辑。经过讨论最终确定条目,随后对其进行修订以保证这些条目体现了会议期间以及会后的讨论思路。摘要CONSORT建议RCT报告的摘要需要有一个结构化的格式,其中应该包括具体的试验目的、试验设计(随机分配的方法、盲法或遮蔽等)、研究对象(对象描述、随机分组的样本量以及用于分析的样本量)、每组实施的干预、实施的干预对主要疗效结果的影响及其危害、试验结论、试验注册名称和编号以及资金来源。本文对每一条能够找到例子的纳入条目都配有良好报告范例、基本原理以及证据等,十分明了易懂,因此我们建议与清单同时使用。结论:摘要CONSORT旨在改善期刊与学术会议中发表的论文摘要的质量,这将有助于摘要提供详尽清晰的信息,这些信息能够帮助读者对试验的有效性和试验结果的适用性做出正确的评价。