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低模量复合全髋关节置换术假体柄的临床和组织学研究结果

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骨科动态 2006年第3期2卷 141-146页

作者： sam AKHAVAN mARY m. mATTHIESEN LEAH SCHULTE TOm PENOYAR mATTHEW J. KRAAY CLARE m. RImNAC VICTOR m. GOLDBERG 白希壮（译） Investigation performed at University Hospitals of Cleveland Cleveland Ohio 中国医科大学附属第一医院骨科沈阳110001

背景：因为假体的股骨柄比股骨有更强的刚度，所以在全髋关节置换患者中更容易产生应力遮挡导致骨溶解。这种关注促进了与正常股骨有相近结构刚度的复合股骨柄植入物的发展。这种假体柄由钴铬合金为轴心，外面包裹聚芳醚酮聚合物和钛网... 详细信息

背景：因为假体的股骨柄比股骨有更强的刚度，所以在全髋关节置换患者中更容易产生应力遮挡导致骨溶解。这种关注促进了与正常股骨有相近结构刚度的复合股骨柄植入物的发展。这种假体柄由钴铬合金为轴心，外面包裹聚芳醚酮聚合物和钛网，有利于骨向内生长。此项研究的目的是确定使用这种假体柄的中期临床、放射学和组织学结果。方法：28例患者（男19例，女9例），平均年龄51.3岁。使用Epoch柄进行初次全髋关节置换手术，平均随访时间6．2年。术前、术后、术后每2年一次分别用Harris髋关节评分以及放射影像学进行研究。此外，术后2年用双能X线吸收测定法扫描评估骨再吸收。尸检获得2块股骨，分别于术后13个月和48个月分析其骨内长入和骨表面长入情况。结果：术前平均Harris髋关节评分为56分，末次随访时提高到97分。双能X线吸收测定法扫描证实2年后平均骨密度在Gruen7区减少最多者为27．5％。放射学证实无假体移位，只有1髋有骨溶解。所有假体柄均有稳定的骨组织固定。组织学评估，术后13个月和48个月尸体股骨标本表明沿整个假体柄平均骨向内长入（标准差）分别为49．63％±13．04％，73．57％±8.48％；平均骨表面长入分别为54．18％±7．68％，80．92％±6．06％。结论：使用Epoch髋关节假体柄后中期随访显示了其良好的临床功能、骨融合的放射学证据、骨向内长入和表面长入的组织学发现。尽管植入物的近期和中期效果良好，但还是有必要通过长期随访评估植入物的远期功能。可信水平：治疗性研究，Ⅳ级。详细的可信水平分级参见作者须知。

关键词：全髋关节置换术临床功能假体柄组织学复合全髋关节置换手术平均年龄 Epoch

Conventional generation emulation for power grids with a high penetration of wind power

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Clean Energy 2021年第1期5卷 93-103页

作者： Rasha El-Azab Eslam m.Wazeer mohamed Daowd A.m.Abdel Ghany Electrical Power and machines Department Faculty of EngineeringHelwan UniversityCairoEgypt

Integrating large-scale wind plants with the electricity grids has many challenges for grid *** the variability and uncertainty of wind power,coordinating between different technologies of generation in the same grid can be considered the main problem,specifically for short-term frequency ***,a large penetration of wind power generation in modern power grids has a risky influence on the power-system ***-generation plants have contradictory behaviour compared to classic thermal plants,especially in active generated power-shortage events due to the variable nature of wind *** experience in wind plants keeps part of the available wind power unloaded,using what are known as deloading *** deloading techniques are usually applied to emulate the thermal-plant-governor function and confirm a proper spinning reserve for any active-power *** techniques decrease the generated power from wind plants continuously from maximum point tracking ***,the practical capacity,annual generated energy and economical income of wind plants are *** addition,grid-protection and control sub-schemes are set and designed according to the well-known conventional responses of thermal plants,which increase the need for thermal-plant-behaviour *** this paper,instead of the usual deloading methods,a supercapacitors scheme is proposed with wind turbines to emulate the response of conventional power *** study discusses the technical and economic benefits of the proposed addition of supercapacitors in the wind-plant-planning *** frequency grid-code indices are selected to evaluate studied *** results of the IEEE four-generation two-area system determines the effectiveness of suggested schemes *** System Advisor model(sam)program estimates the economic benefits of a typical US study case compared with the existing wind-deloading technique.

关键词： wind energy planning analysis energy storage supercapacitor frequency stability

modulational Instability of Optical Vortices in Engineered Saturable media

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Engineering 2022年第10期17卷 31-43页

作者： D.G.Pires N.m.Litchinitser Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA

Propagation of light beams in turbid media such as underwater environments,fog,clouds,or biological tissues finds increasingly important applications in science and technology,including bio-imaging,underwater communication,and free-space communication *** many of these applications traditionally relied on conventional,linearly polarized Gaussian beams,light possesses many degrees of freedom that are still largely unexplored,such as spin angular momentum(sam)and orbital angular momentum(OAm).Here,we present nonlinear light-matter interactions of such complex light beams with"rotational"degrees of freedom in engineered nonlinear colloidal *** making use of both variational and perturbative approach,we consider non-cylindrical optical vortices,elliptical optical vortices,and higher-order Bessel beams integrated in time(HOBBIT)to predict the dynamics and stability of the evolution of these *** results may find applications in many scenarios involving light transmission in strongly scattering environments.

关键词： Optical vortex Orbital angular momentum modulation instability Turbid media

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厄瓜多尔的土壤保护

水土保持应用技术 1983年第4期 38-40页

作者： sam Portch Jesse L.Hicks ,张天义

近些年来,厄瓜多尔的土壤学家及其农业部门的官员已经开始关注境内的土壤侵蚀问题.政府农业部设立了土壤保护机构.但其工作性质和其它部门不尽相同,由于缺乏农民的支持和政治、经济方面原因,开展工作比较困难.1952年,m.阿克斯达·索利... 详细信息

近些年来,厄瓜多尔的土壤学家及其农业部门的官员已经开始关注境内的土壤侵蚀问题.政府农业部设立了土壤保护机构.但其工作性质和其它部门不尽相同,由于缺乏农民的支持和政治、经济方面原因,开展工作比较困难.1952年,m.阿克斯达·索利斯编写了一本关于水土保护方面的专著.内容是论述厄瓜多尔的严重的土壤侵蚀问题,并

关键词：厄瓜多尔美国南美洲美利坚合众国北美洲土壤保护土地保护希克斯农民劳动者土壤保持

Dual color optogenetic control of neural populations using low-noise,multishank optoelectrodes

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microsystems & Nanoengineering 2018年第1期4卷 309-324页

作者： Komal Kampasi Daniel F.English John Seymour Eran Stark sam mcKenzie mihály Vöröslakos György Buzsáki Kensall D.Wise Euisik Yoon Department of Biomedical Engineering University of MichiganAnn ArborMI 48105USA Center for micro and Nanotechnology Lawrence Livermore National LaboratoryLivermoreCA 94550USA NYU Neuroscience Institute School of MedicineEast River Science ParkAlexandria Center450 East 29th St9th FloorNew YorkNY 10016USA Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMI 48105USA Department of Physiology and Pharmacology Sackler Faculty of MedicineTel Aviv University69978 Tel AvivIsrael Sagol School of Neuroscience Tel Aviv University69978 Tel AvivIsrael

Optogenetics allows for optical manipulation of neuronal activity and has been increasingly combined with intracellular and extracellular electrophysiological ***-identified classes of neurons are optically manipulated,though the versatility of optogenetics would be increased if independent control of distinct neural populations could be achieved on a sufficient spatial and temporal *** report a scalable multisite optoelectrode design that allows simultaneous optogenetic control of two spatially intermingled neuronal populations in *** describe the design,fabrication,and assembly of low-noise,multisite/multicolor *** shank of the four-shank assembly is monolithically integrated with 8 recording sites and a dualcolor waveguide mixer with a 7×30μm cross-section,coupled to 405 nm and 635 nm injection laser diodes(ILDs)via gradient-index(GRIN)lenses to meet optical and thermal design *** better understand noise on the recording channels generated during diode-based activation,we developed a lumped-circuit modeling approach for EmI coupling mechanisms and used it to limit artifacts to amplitudes under 100μV upto an optical output power of 450μ*** implanted the packaged devices into the CA1 pyramidal layer of awake mice,expressing Channelrhodopsin-2 in pyramidal cells and ChrimsonR in paravalbumin-expressing interneurons,and achieved optical excitation of each cell type using sub-mW *** highlight the potential use of this technology for functional dissection of neural circuits.

关键词： waveguide mixer neural

Surface Characterisation of Silicon Based mEmS

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Chemical Research in Chinese Universities 2004年第4期20卷 407-410页

作者： LI J. CUI Z m. A. Baker The Surface Analysis Laboratory School of Engineering University of SurreyRutherford Appleton LaboratoryThe Surface Analysis Laboratory School of Engineering University of Surrey Guildford GU2 7XH UKChilton Didcot UKGuildford GU2 7XH UK

Polysilicon microelectromechanical systems(mEmS) are the subject of intensive researches. Surface chemistry and topography of a mEmS test structure fabricated at Sandia National Laboratory, USA, were studied by means of scanning electron microscopy(SEm), X-ray photoelectron spectroscopy(XPS) and atomic force microscopy(AFm). XPS C_ 1sand Si_ 2pspectra from the polysilicon components, silicon nitride substrate and a reference silicon wafer were compared. The results confirm the presence of a self-assembled monolayer(sam) on the mEmS surface. An island-like morphology was found on both polysilicon and silicon nitride surfaces of the mEmS. The islands take the form of caps, being up to 0.5 μm in diameter and 20 nm in height. It is concluded that the co-existence of columnar growth and equiaxed growth during the low pressure chemical vapor deposition(LPCVD) of these layers leads to the observed morphology and the islands are caps to the columnar structures.

关键词： microelectromechanical systems XPS Atomic force microscopy

Genetic and healthy lifestyle factors in relation to the incidence and prognosis of severe liver disease in the Chinese population

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Chinese medical Journal 2023年第16期136卷 1929-1936页

作者： Yuanjie Pang Jun Lv Christiana Kartsonaki Canqing Yu Yu Guo Yiping Chen Ling Yang Iona Y.millwood Robin G.Walters Silu Lv Sushila Burgess sam Sansome Junshi Chen Zhengming Chen Liming Li Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Key Laboratory of Epidemiology of major Diseases(Peking University) Ministry of EducationBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Nuffield Department of Population Health Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU)University of OxfordOxford OX37LFUK Nuffield Department of Population Health Medical Research Council Population Health Research Unit(MRC PHRU)at the University of OxfordUniversity of OxfordOxford OX37LFUK National Clinical Research Center of Cardiovascular Diseases National Center for Cardiovascular DiseasesBeijing 100730China Fuwai Hospital Chinese Academy of Medical Sciences167 Beilishi RoadXicheng DistrictBeijing 100037China Licang Center for Disease Prevention and Control Licang DistrictQingdaoShandong 266041China National Center for Food Safety Risk Assessment Beijing 100021China

Background:Severe liver disease(SLD),including cirrhosis and liver cancer,constitutes a major disease burden in *** aimed to examine the association of genetic and healthy lifestyle factors with the incidence and prognosis of ***:The study population included 504,009 participants from the prospective China Kadoorie Biobank aged 30-79 *** individuals were from 10 diverse areas in China without a history of cancer or liver disease at *** regression was used to estimate adjusted hazard ratios(HRs)for incident SLD and death after SLD diagnosis associated with healthy lifestyle factors(smoking,alcohol,physical activity,and central adiposity).Additionally,the contribution of genetic risk for hepatitis B virus(HBV,assessed by genetic variants in major histocompatibility complex,class II,DP/DQ[HLA-DP/DQ]genes)was also ***:Compared with those with 0-1 healthy lifestyle factor,participants with 2,3,and 4 factors had 12%(HR 0.88[95%confidence interval[CI]0.85,0.92]),26%(HR 0.74[95%CI:0.69,0.79]),and 44%(HR 0.56[95%CI:0.48,0.65])lower risks of SLD,*** associations were observed among participants with both low and high genetic risks(HR per 1-point increase 0.83[95%CI:0.74,0.94]and 0.91[95%CI:0.82,1.02],respectively;P_(interaction)=0.51),although with a non-significant trend among those with a high genetic *** associations were also observed between healthy lifestyle factors and liver biomarkers regardless of the genetic *** the limited power,healthy lifestyle factors were associated with a lower risk of death after incident SLD among participants with a low genetic risk(HR 0.59[95%CI:0.37,0.96]).Conclusions:Lifestyle modification may be beneficial in terms of lowering the risk of SLD regardless of the genetic ***,it is also important for improving the prognosis of SLD in individuals with a low genetic *** studies are warranted to examine the impact of healthy lifestyles on SLD prognos

关键词： Healthy lifestyle Gene-environment interaction Liver cancer Cirrhosis Prognosis China

Characterization of Novel Torrefied Biomass and Biochar Amendments

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Agricultural Sciences 2020年第2期11卷 157-177页

作者： Heather D. Baldi Tyler L. Foster Xiaoqing Shen sam E. Feagley Fred E. Smeins Dirk B. Hays Russell W. Jessup Department of Soil & Crop Sciences Texas A&M University College Station TX USA Department of Ecosystem Science and management Texas A&M University College Station TX USA

Nutrient management is vital for food, feed, fiber, and fuel production. However, excessive application and loss (volatilization, leaching, run-off, etc.) of inorganic and organic sources of nutrients have detrimental environmental impacts, while increasing prices for petroleum-based and mined fertilizers further limit opportunities for their utilization in developing nations. This study evaluated a novel, alternative type of nutrient source through pretreatment processes of torrefaction and pyrolysis by converting high-biomass feedstocks into renewable soil amendments. Napiergrass (Pennisetum purpureum Schumach., [cv. merkeron]) and pearl millet—napiergrass (Pennisetum glaucum [L.] R. Br. × P. purpureum Schumach.) (PmN) were converted under atmospheric pressure with minimal oxygen at 250°C and 400°C, ground to 1 millimeter (mm) and 2 mm particle sizes, and compared to urea in a full-season field trial and short-season nursery trial growing maize (Zea mays L.) and PmN for fertility response. When compared to urea in the field trial, the torrefied biomass amendment (TBA) and biochar had similar responses despite lower nitrogen (N) application rates. The nursery trial also produced equivalent responses from urea and TBA regardless of lower N application with the exception being phosphorus (P). Finally, maize and PmN had higher P uptake with the TBA in both trials.

关键词： Torrefaction Biochar Pyrolysis Soil Amendment Organic Nutrient Source

Erratum to:Carbonatites and Alkaline Igneous Rocks in Post-Collisional Settings:Storehouses of Rare Earth Elements

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Journal of Earth Science 2022年第4期33卷 1059-1059页

作者： Kathryn m.Goodenough Eimear A.Deady Charles D.Beard sam Broom-Fendley Holly A.L.Eliott Frederick van den Berg Husey in Oztirk British Geological Survey the lyell CentreEdinbungh EHI44APUK Instut des Sciences de la Terre Universite Grenoble Alpes38610 GieresFrance Camborme School of mines Universiy of ExererPenryn CampusPenryn TRI09FEUK School of Environmental Sciences University of DerbyDerbyUK Depurtment of Geological Engineering Istanbul Uiniversity-CerrahpasaAvclar Campus34320 Avclar IstanbulTurtkey

This article was orignally published ectronically on the publisher's internet portal on 23 August *** the author(s)'deeision,the copyright of the article changed on 27 of January 2022 to◎Brtish Geological Survey,UKRI 2022 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distri-bution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons lcece,and indicate if changes were made.

关键词： Earth source Rare