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Systematic review of atorvastatin for the treatment of Alzheimer's disease

Neural Regeneration Research 2012年第17期7卷 1344-1351页

作者： Yuan Sun Genfa wang Zhihong Pan shuyan Chen Department of Gerontology Xinhua Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200092 China

OBJECTIVE： To assess the clinical efficacy and safety of atorvastatin in the treatment of Alzheimer＇s disease. DATA SOURCES： Medline （1948/2011-04）, Embase （1966/2011-04）, Cochrane Library （Issue 3, 2011）, Chinese National Knowledge Infrastructure （1989/2011-04）, and the Chinese Biomedical Literature Database （1979/2011-04） were searched for randomized clinical trials regardless of language. Abstracts of conference papers were manually searched. Furthermore, Current Controlled Trials （http：//***）, Clinical *** （http：//***）, and Chinese Clinical Trial Registry （http：//***） were also searched. Key words included AIzheimer disease, dementia, cognition, affection, memory dysfunction, hydroxymethylglutaryI-CoA reductase inhibitors, atorvastatin and statins. DATA SELECTION： Randomized controlled trials of grade A or B according to quality evaluation criteria of the Cochrane Collaboration were selected, in which atorvastatin and placebo were used to evaluate the effects of atorvastatin in the treatment of Alzheimer＇s disease. Study methodological quality was evaluated based on criteria described in Cochrane Reviewer＇s Handbook 5.0.1. Revman 5.1 software was used for data analysis. MAIN OUTCOME MEASURES： Clinical efficacy, safety, withdrawal from the studies, and withdrawal due to adverse effects. RESULTS： Two randomized controlled trials were included, one was scale A, and the other was scale B. All patients （n = 710, age range 50-90 years） were diagnosed as probable or possible mild to moderate Alzheimer＇s disease according to standard criteria and treated with atorvastatin 80 mg/d or placebo. There was no difference between the two groups in the final follow-up for Clinical Global Impression of Change scale （WMD = 0.13, 95%CI： 0.15 to 0.40）, the Alzheimer＇s Disease Assessment Scale-cognitive subscale （WMD = 1.05, 95%C1：-3.06 to 6.05）, Mini-Mental State Examination Scale （WMD = 0.77, 95%CI： 0.57 to 2.10）, and the Neuropsy

关键词： Alzheimer's disease dementia atorvastin diphosphonate systematic review neural regeneration

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Gear geometry of cycloid drives

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Science China(Technological Sciences) 2008年第5期51卷 598-610页

作者： CHEN BingKui FANG TingTing LI ChaoYang wang shuyan State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China

According to differential geometry and gear geometry, the equation of meshing for small teeth difference planetary gearing and a universal equation of conjugated profile are established based on cylindrical pin tooth and given motion. The correct meshing condition, contact line, contact ratio, calculating method for pin tooth's maximum contact point are developed. Investigation on the theory of conjugated meshing is carried out when the tooth difference numbers between pin wheel and cycloidal gear are 1, 2, 3 and ?1, respectively. A general method called enveloping method to generate hypocycloid and epicycloid is put forward. The correct meshing condition for cycloid pin wheel gearing is provided, and the contact line and the contact ratio are also discussed.

关键词： pin wheel cycloid conjugated profile equation of meshing enveloping method contact ratio contact line

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孵化期紫外线和绿光照射对茶花鸡胚胎及雏鸡生长的影响

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中国家禽 2024年第4期46卷 67-72页

作者：赖金花杨雨鲁绍雄王孝义陈强王淑燕李明丽云南农业大学动物科学技术学院云南昆明650201

试验旨在揭示孵化期中波紫外线和绿光照射对茶花鸡胚胎及雏鸡生长的影响。试验选择茶花鸡种蛋450个,随机分为对照组、紫外线组和绿光组,每组150个种蛋。在种蛋孵化0~18 d,对照组不作任何光照处理,紫外线组每天连续接受30 min中波紫外线... 详细信息

试验旨在揭示孵化期中波紫外线和绿光照射对茶花鸡胚胎及雏鸡生长的影响。试验选择茶花鸡种蛋450个,随机分为对照组、紫外线组和绿光组,每组150个种蛋。在种蛋孵化0~18 d,对照组不作任何光照处理,紫外线组每天连续接受30 min中波紫外线(照射剂量12.75μW·h/cm^(2))照射,绿光组每天连续接受12 h绿光(光照强度523 lx)照射,测定并分析各处理组孵化后期胚胎和出壳后2周内雏鸡的生长指标差异。结果显示:在孵化期内,紫外线组14 d、16 d、18 d胚胎重和体长以及14 d、16 d心脏重显著高于对照组(P0.05);绿光组仅16 d心脏重和18 d胚胎体长显著高于对照组(P<0.05)。出壳后,紫外线组雏鸡的0、7、14日龄体重、体长、胫骨长、跖骨长、胸宽和胸深显著高于对照组(P<0.05或P<0.01),0日龄体长和胫骨长,7日龄体重、胫骨长、跖骨长和胸深,14日龄体重和胫骨长显著高于绿光组(P<0.05或P<0.01);绿光组雏鸡3个日龄体重、0日龄胸宽和胸深、7日龄体长及14日龄胸宽显著高于对照组(P<0.05或P<0.01)。综上可见,孵化期接受适量中波紫外线或绿光照射可促进鸡胚和雏鸡生长,且紫外线照射的效果总体上优于绿光。

关键词：中波紫外线绿光茶花鸡胚胎发育雏鸡生长

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Cu含量对铝锂合金局部腐蚀行为的影响

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中国有色金属学报 2024年第8期34卷 2559-2570页

作者：杨惠钧唐建国李响刘锦勋李红英肖翔林海涛王姝俨中南大学材料科学与工程学院长沙410083 中南大学有色金属材料科学与工程教育部重点实验室长沙410083 中铝材料应用研究院有限公司北京102209 西南铝业(集团)有限责任公司重庆401326

通过晶间腐蚀、剥落腐蚀和电化学实验,结合金相显微镜、扫描电子显微镜和透射电子显微镜对组织的观察,研究了三种Cu含量对铝锂合金局部腐蚀行为的影响。结果表明:三种Cu含量铝锂合金(3.15Cu、3.63Cu和3.88Cu合金)的抗腐蚀性能由好到差... 详细信息

通过晶间腐蚀、剥落腐蚀和电化学实验,结合金相显微镜、扫描电子显微镜和透射电子显微镜对组织的观察,研究了三种Cu含量对铝锂合金局部腐蚀行为的影响。结果表明:三种Cu含量铝锂合金(3.15Cu、3.63Cu和3.88Cu合金)的抗腐蚀性能由好到差依次为3.15Cu合金、3.88Cu合金、3.63Cu合金。3.15Cu合金中粗大相和T1相的数量最少,腐蚀深度最浅,腐蚀电流密度最小,EIS容抗弧半径最大,具有最好的抗腐蚀性能。与3.15Cu合金相比,3.63Cu和3.88Cu合金中粗大相和T1相的数量较多,导致合金腐蚀更容易萌生和扩展,使抗腐蚀性能变差;与3.63Cu合金相比,3.88Cu合金中粗大相与基体间的电位差减小,使抗腐蚀性能略有提升。

关键词：铝锂合金 Cu含量局部腐蚀晶间腐蚀剥落腐蚀

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Investigation on effect of drag models on flow behavior of power-law fluid–solid two-phase flow in fluidized bed

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Particuology 2022年第11期70卷 43-54页

作者： Zihan Yuan shuyan wang Baoli Shao Lei Xie Yujia Chen Yimei Ma Key Laboratory of Enhanced Oil Recovery of Ministry of Education School of Petroleum EngineeringNortheast Petroleum UniversityDaqing 163318China

In this study,a Eulerian-Eulerian two-fluid model combined with the kinetic theory of granular flow is adopted to simulate power-law fluid–solid two-phase flow in the fluidized *** new power-law liquid–solid drag models are proposed based on the rheological equation of power-law fluid and pressure *** called model A is a modified drag model considering tortuosity of flow channel and ratio of the throat to pore,and the other called model B is a blending drag model combining drag coefficients of high and low particle *** are compared with experimental data measured by Lali et al.,where the computed porosities from model B are closer to the measured data than other ***,the predicted pressure drop rises as liquid velocity increases,while it decreases with the increase of particle *** results indicate that the increases of consistency coefficient and flow behavior index lead to the decrease of drag coefficient,and particle concentration,granular temperature,granular pressure,and granular viscosity go down accordingly.

关键词： Power-law liquid-solid drag models Power-law fluid Liquid-solid two-phase flow Eulerian-Eulerian two-fluid model

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Numerical simulation of gas-solid flow with two fluid model in a spouted-fluid bed

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Particuology 2014年第3期12卷 109-116页

作者： shuyan wang Liqian Zhao Chunsheng wang Yinsong Liu Jinsen Gao Yang Liu Qinglin Cheng School of Petroleum Engineering Northeast Petroleum University State Key Laboratory of Heavy Oil Processing China University of Petroleum

The flow characteristics in a spouted-fluid bed differ from those in spouted or fluidized beds because of the injection of the spouting gas and the introduction of a fluidizing gas. The flow behavior of gas-solid phases was predicted using the Eulerian-Eulerian two-fluid model （TFM） approach with kinetic theory for granular flow to obtain the flow patterns in spouted-fluid beds. The gas flux and gas incident angle have a significant influence on the porosity and particle concentration in gas-solid spouted-fluid beds. The fluidizing gas flux affects the flow behavior of particles in the fountain. In the spouted-fluid bed, the solids volume fraction is low in the spout and high in the annulus. However, the solids volume fraction is reduced near the wall.

关键词： Spouted-fluid bed Two fluid modeling CFD Fluidization

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Microstructural characteristics of cold-rolled Zr-2.5Nb alloy annealed near the monotectoid temperature

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Science China(Technological Sciences) 2018年第4期61卷 558-566页

作者： CHAI LinJiang WU Hao wang shuyan LUAN BaiFeng WU Yue HUANG XiaoYu College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China College of Materials Scienceand Engineering Chongqing UniversityChongqing 4000044China

A dual-phase Zr-2.5 Nb alloy was rolled at room temperature to 50% reduction and then annealed at two temperatures(560 and580°C) near the monotectoid temperature. X-ray diffraction, electron channeling contrast imaging and electron backscatter diffraction techniques were jointly used to characterize microstructural characteristics developed in the as-rolled and annealed specimens. Results show that plastic deformation occurs in both bulk α-Zr grains and thin β-Zr films during rolling, allowing large lattice strains to be accumulated in β-Zr and active dislocation slip(especially the prismatic áa?slip) to be initiated in α-Zr. During subsequent annealing at 580°C, the prior β-Zr films are transformed into submicron β-Zr particles, which lose coherency(the Burgers orientation relationship) with surrounding α grains. In the specimen annealed at 560°C, however, the prior β-Zr films are found to be decomposed into nanoscale β-Nb particles. In both the annealed specimens, the β-Zr and the β-Nb particles appeared to be linearly distributed along the rolling direction. Two types of α structures, i.e., small equiaxed crystallites formed by recovery of dislocation structures and coarse bamboo-like recrystallized grains, are revealed in the annealed specimens. Effective boundary pinning due to the dense β-phase particles is demonstrated to play a key role in forming such unusual bamboo-like grains.

关键词： Zr alloy dual-phase microstructure rolling recrystallization electron backscatter diffraction

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Cloning and characterization of a new endo-type polyG-specific alginate lyase from bacteria Vibrio sp. QD-5

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Acta Oceanologica Sinica 2019年第6期38卷 65-74页

作者： Yaxi Chao shuyan wang Suqi Wu Jiaqiang Wei Hao Chen Key Laboratory of Marine Bioactive Substances First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology (Qingdao)Qingdao 266237China

Seven bacterial clones with alginate-utilizing activity were isolated from rotten kelp. By activity test, the Vibrio sp. QD-5 with the potential alginate-degrading capability was chosen to carry out the draft genome sequencing, and the result showed that the Vibrio sp. QD-5 containing an alginate lyase gene cluster. One of these genes, aly-IV, was cloned and characterized for the first time. After overexpression, Aly-IV, with a molecular mass of about 62 kDa and a theoretical isoelectric point (pI) of 5.12, was purified to a specific activity of 1 256.78 U/mg and showed highest activity at 35°C in the Tris-HCl buffer at pH of 8.9. Moreover, the enzyme activity was enhanced by the metal ions of Na+, K+ and Mg2+ under certain concentration. Aly-IV degraded favorably polyG blocks in an endo-type, yielding monomer and dimer as the main products. Due to its high substrate specificity, Aly-IV could be used as a potential tool for production of polyG oligosaccharides with low degree of polymerization (DP) and for determining the fine structure of alginate.

关键词： alginate lyase Vibrio sp. alginate poly-α-L-guluronic acid lyase oligosaccharides

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济南城区冬季PM_(2.5)中硝基苯酚类化合物昼夜变化特征及生成机理

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环境化学 2024年第9期43卷 3152-3164页

作者：范晶刘晨苑金鹏张桂芹魏小锋王淑妍孙友敏山东建筑大学市政与环境工程学院济南250101 齐鲁工业大学(山东省科学院)山东省分析测试中心济南250101 山东建筑大学资源与环境创新研究院济南250101

硝基苯酚类化合物(Nitrophenols,NPs)是细颗粒物中含氮有机物的重要组成部分,来自于污染源的一次排放或由前体物经过二次反应生成.采集了济南城区2021年12月17日—2022年1月19日冬季大气昼夜PM_(2.5)样品,利用超高效液相色谱-质谱联用... 详细信息

硝基苯酚类化合物(Nitrophenols,NPs)是细颗粒物中含氮有机物的重要组成部分,来自于污染源的一次排放或由前体物经过二次反应生成.采集了济南城区2021年12月17日—2022年1月19日冬季大气昼夜PM_(2.5)样品,利用超高效液相色谱-质谱联用仪定量分析了样品中的7种硝基苯酚类化合物.结果表明,济南市区冬季大气PM_(2.5)中ρ(∑NPs)范围为13.22—72.42 ng·m^(-3),平均值为(45.56±13.22)ng·m^(-3).单个硝基苯酚类化合物中,4-硝基苯酚(4NP)占比最大,与国内其他城市监测结果一致.清洁天和污染天对比分析发现硝基苯酚类化合物在污染天的浓度更高,除4-硝基愈创木酚和5-硝基邻甲氧基苯酚外,其余硝基苯酚类化合物均是污染天浓度高.昼夜浓度对比发现ρ(∑NPs)在白天和夜间时段分别为(41.5±16.35)ng·m^(-3)和(49.08±20.18)ng·m^(-3),大部分硝基苯酚类化合物的昼夜浓度呈现夜间浓度高于白天,但PM_(2.5)污染加重时,白天时段的硝基苯酚类化合物浓度明显升高,甚至高于夜间浓度.利用量子化学高斯程序计算发现夜间硝基苯酚生成更容易,这跟晚上时段观测的硝基苯酚浓度高的现象相一致.当苯酚邻位和对位的取代基是给电子基团可以减小O—H解离焓,有利于苯氧自由基的生成.化学反应动力学给出了2-硝基苯酚(2NP)和4NP的生成路径,其反应活化能分别为49.6 kcal·mol^(-1)和84.2 kcal·mol^(-1),生成速率常数分别为7.93×10^(-37) cm^(3)·molecules^(-1)·s^(-1)和5.75×10^(-60) cm^(3)·molecules^(-1)·s^(-1),可知在清洁干燥天气的时候,硝基苯酚化合物的生成是非常困难的.但当有水分子和氨气等催化剂的协助后,2NP和4NP生成的活化能明显减小,其生成反应速率常数显著增大,说明重污染过程中,湿度增加和有氨气存在时会促进硝基苯酚的生成和积累.研究结果为城市氮氧化物削减和含氮有机物的二次生成提供一定的科学支撑.

关键词：硝基苯酚超高效液相色谱-质谱联用仪 PM_(2.5) 生成机制

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遥感卫星任务智能决策的机器学习方法研究

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航天器工程 2024年第4期33卷 1-10页

作者：杨芳景丽萍黄敏陈雄姿田帅虎王抒雁张宝昕航天东方红卫星有限公司北京100094 北京交通大学交通数据分析与挖掘北京市重点实验室北京100044

基于遥感卫星任务决策的特点,研究如何采用机器学习方法对执行任务时产生的大量动作、指令和遥测数据进行分析和训练。为了给遥感卫星任务建立机器学习方法,探索机器学习辅助遥感卫星任务智能决策的可行性,并探讨机器学习模型对卫星任... 详细信息

基于遥感卫星任务决策的特点,研究如何采用机器学习方法对执行任务时产生的大量动作、指令和遥测数据进行分析和训练。为了给遥感卫星任务建立机器学习方法,探索机器学习辅助遥感卫星任务智能决策的可行性,并探讨机器学习模型对卫星任务数据的适应性和处理效率。借鉴地面相关人工智能系统成熟的机器学习架构,研究建立遥感卫星任务相关智能决策的机器学习方法,并给出了机器学习的样例。研究结果表明:机器学习方法的适应性很强,初步实现了遥感卫星自主任务决策,并达到一定的准确率,对卫星任务智能决策技术进行了有益探索。

关键词：遥感卫星任务智能决策机器学习样本模型

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