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Heart failure in the elderly-some aspects in pathophysiology,diagnosis and therapy that require special attention

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Journal of Geriatric Cardiology 2007年第1期4卷 44-49页

作者： Ernst r. Schwarz Division of Cardiology and Comprehensive Transplant Center Department of Medicine Cedars Sinai Medical Center & University of California Los Angeles (UCLA) Los Angeles California USA

Approximately 50% of all heart failure patients in the US are above 75 years of age, which is almost similar to most European countries and the Middle and the Far East. Even though aging is an independent molecular process with a multitude of genetic predetermination and biochemical mediations, aging itself does not automatically result in cardiac insufficiency. On the other hand, with increasing age, cardioprotective mechanisms in response to stress are lost, and progressive cardiomyocyte degeneration with replace- ment fibrosis is often seen in older hearts, even though the exact triggers are not completely understood. Older patients with heart failure have distinct features that require special attention in diagnosis as well as therapy. The elderly more frequently suffer from multiple co-morbidities and might have atypical clinical presentations. Several precautions are essential in the treatment of heart failure in the elderly due to co-existing morbidities and the pharmacokinetic and pharmacodynamic changes related to increased age. Also, treatment expectations, compliance, mental status and cognitive function might play a major role regarding optimized treatment and monitoring options in the elderly suffering from heart failure. This review summarizes current issues of heart failure management in the elderly.

关键词： heart failure aging left ventricular function mortality elderly

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On FWHEP

Acta Mathematica Sinica,English Series 1994年第3期10卷 301-307页

作者： r.W.Kieboom Department of Mathematics Vrije Universiteit Brussel Pleinlaan 2-F10 B-1050 BRUSSELBelgium

This paper introduced a new homotopy extension property called the fairly weak homotopy extension property(FWHEP)and showed some its characterizations and properties. The FWHEP is strictly between the WHEP and the VWH... 详细信息

关键词： On FWHEP Math

Structural,Dielectric and Complex Impedance Spectroscopy Studies of Lead Free Ca_(0.5+x)Nd_(0.5-x)(Ti_(0.5)Fe_(0.5))O_3

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Journal of Materials Science & Technology 2013年第4期29卷 323-329页

作者： M.r.Shah A.K.M.Akther Hossain Department of Physics University of PrimeasiaBananiDhaka 1213Bangladesh Department of Physics Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （rgb） is observed. The rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.

关键词： Crystal structure Dielectric properties Lead free Perovskite Solid state reaction

Increased Temperature and Entropy Production in the Earth’s Atmosphere: Effect on Wind, Precipitation, Chemical reactions, Freezing and Melting of Ice and Electrical Activity

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Journal of Modern Physics 2019年第8期10卷 966-973页

作者： michael A. Pitt Paraparaumu New Zealand

Since the late nineteenth century, until the present time, there has been an increase in the earth’s global mean surface temperature (GMST). This temperature increase has been calculated at 0.85°C over the period 1880-2012. The causes of this temperature increase include increased levels of greenhouse gases (GHG’s), variations in solar irradiance and changes in absorption and re-radiation of heat. Volcanic activity and orbital cycles work to cool the earth’s surface. A thermodynamic analysis is presented of the earth’s atmosphere. The analysis demonstrates an increase in entropy production as a result of increased GMST. An equation is derived expressing entropy production in the atmosphere based on atmospheric processes (wind, precipitation, chemical reactions, electrical activity and heat transfer). The effects of increased entropy production on wind, precipitation, freezing and melting of ice, chemical reactions and electrical activity are given showing an increase in the combination of the above phenomena.

关键词： Temperature Entropy Earth’s Atmosphere

Microstructures and impact toughness behavior of Al 5083 alloy processed by cryorolling and afterwards annealing

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 759-769页

作者： Dharmendra Singh P.Nageswara rao r.Jayaganthan Department of Metallurgical and Materials Engineering Indian Institute of Technology RoorkeeRoorkee-247667India

The influence of rolling at liquid nitrogen temperature and annealing on the microstructure and mechanical properties of Al 5083 alloy was studied in this paper. Cryorolled samples of Al 5083 show significant improvements in strength and hardness. The ultimate tensile strength increases up to 340 MPa and 390 MPa for the 30% and 50% cryorolled samples, respectively. The cryorolled samples, with 30% and 50% reduction, were subjected to Charpy impact testing at various temperatures from 190℃ to 100℃. It is observed that increasing the percentage of reduction of samples during cryorolling has significant effect on decreasing impact toughness at all temperatures by increasing yield strength and decreasing ductility. Annealing of samples after cryorolling shows remarkable increment in impact toughness through recovery and recrystallization. The average grain size of the 50% cryorolled sample （14 μm） after annealing at 350℃ for 1 h is found to be finer than that of the 30% cryorolled sample （25 μm）. The scanning electron microscopy （SEM） analysis of fractured surfaces shows a large-size dimpled morphology, resembling the ductile fracture mechanism in the starting material and fibrous structure with very fine dimples in cryorolled samples corresponding to the brittle fracture mechanism.

关键词： aluminum alloys cryorolling annealing microstructure impact toughness recovery recrystallization

Influence of recycled polyethylene terephthalate fibres on plastic shrinkage and mechanical properties of concrete

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 792-802页

作者： NecatÖZAŞIK Özgür ErEN Department of Civil Engineering Eastern Mediterranean UniversityMersin 99628Turkey

Polyethylene terephthalate bottles production has drastically increased year after year due to high versatility of polyethylene terephthalate plastics and considerable consumption of *** tandem with that increase,the major concern of society has been the improper disposal of this non-biodegradable material to the *** deal with this concern,recycled polyethylene terephthalate bottles were incorporated in concrete as fibre reinforcements in this *** objective of this research is to evaluate the mechanical properties of recycled polyethylene terephthalate fibre reinforced concrete(rPFrC)in comparison with control concrete without *** terephthalate fibres with three different diameters(0.45,0.65,and 1.0 mm)and two lengths(20 and 30 mm)were added at various proportions(0.5%,1.0%,1.5%and 2.0%)by volume of concrete in order to determine the effect of fibres initially on compressive,flexural and splitting tensile strengths of *** results revealed that none of the fibres have detrimental effects up to 1%volume fraction,however further addition caused slight reductions on mechanical properties in some *** shrinkage resistance and impact resistance tests were also performed according to related *** terephthalate fibres were observed to have marked improvements on those *** a good performance could be attributed primarily to the bridging effect of fibres.

关键词： recycled PET fibre-reinforced concrete mechanical properties plastic shrinkage impact energy

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塑料零件生产中涂漆工艺的合理设计

世界汽车 1986年第5期 54-58页

作者： Uerich hoffmann 白葆山

一、问题的范围汽车结构件中塑料的采用正在不断增加,在汽车车身和车身附件中尤有增加的趋势,诸如发动机罩、后视镜支架、油箱盖、移动式顶棚、保险杠、导流板和轮罩等。这就意味着:在汽车制造业中应当进行涂漆的塑料零件数量也在增加。

关键词：塑料零件涂漆工艺分模面静电涂敷模具表面底漆硅树脂内涂层侵蚀性介质汽车车身

SUPErAPPrOXIMATION PrOPErTIES OF THE INTErPOLATION OPErATOr OF PrOJECTION TYPE AND APPLICATIONS

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Journal of Computational Mathematics 2002年第3期20卷 277-288页

作者： Tie Zhang Yan-ping Lin r.J.Tait Department of Mathematics Northeastern UniversityShenyang 110006China Department of Mathematical Sciences University of AlbertaCanadaT6G 2G1

Presents information on a study which analyzed superapproximation properties for the interpolation operator of projection type on two-dimensional domain. Discussion on the interpolation operator of projection type and its superapproximation properties; Superconvergence of ritz projection; Proof and applications of the superconveregence of ritz-Volterra projection.

关键词： interpolation operator of projection type finite element superconvergence

rediscovering Don Swanson:The Past,Present and Future of Literature-based Discovery

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Journal of Data and Information Science 2017年第4期2卷 43-64页

作者： Neil r.Smalheiser Department of Psychiatry University of Illinois at ChicagoChicagoIL 60612USA

Purpose： The late Don r. Swanson was well appreciated during his lifetime as Dean of the Graduate Library School at University of Chicago, as winner of the American Society for Information Science Award of Merit for 2000, and as author of many seminal articles. In this informal essay, I will give my personal perspective on Don＇s contributions to science, and outline some current and future directions in literature-based discovery that are rooted in concepts that he ***/methodology/approach： Personal recollections and literature review. Findings： The Swanson A-B-C model of literature-based discovery has been successfully used by laboratory investigators analyzing their findings and hypotheses. It continues to be a fertile area of research in a wide range of application areas including text mining, drug repurposing, studies of scientific innovation, knowledge discovery in databases, and bioinformatics. recently, additional modes of discovery that do not follow the A-B-C model have also been proposed and explored （e.g. so-called storytelling, gaps, analogies, link prediction, negative consensus, outliers, and revival of neglected or discarded research questions）. research limitations： This paper reflects the opinions of the author and is not a comprehensive nor technically based review of literature-based discovery. Practical implications： The general scientific public is still not aware of the availability of tools for literature-based discovery. Our Arrowsmith project site maintains a suite of discovery tools that are free and open to the public （http：//***）, as does BITOLA which is maintained by Dmitar Hristovski （http：// http：//***/bitola）, and Epiphanet which is maintained by Trevor Cohen （http：//***/）. Bringing user-friendly tools to the public should be a high priority, since even more than advancing basic research in informatics, it is vital that we ensure that scientists actually use discovery t

关键词： Literature-based discovery Biography Text mining Knowledge discovery indatabases Implicit information Information science