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World Journal of Cardiology 2015年第2期7卷 65-75页

作者： Sven M bius-Winkler Nicolas Majunke Marcus Sandri norman mangner Axel Linke Gregg W Stone Ingo D hnert Gerhard Schuler Peter B Sick Department of Internal Medicine/Cardiology University of LeipzigHeart Center Columbia University Medical Center Department of Pediatric Cardiology University of LeipzigHeart Center Clinic for Cardiology Hospital Barmherzige Brueder

Transcatheter closure of the left atrial appendage has been developed as an alternative to chronic oral anticoagulation for stroke prevention in patients with atrial fibrillation, and as a primary therapy for patients with contraindications to chronic oral anticoagulation. The promise of this new intervention compared with warfarin has been supported by several, small studies and two pivotal randomized trial with the Watchman Device. The results regarding risk reduction for stroke have been favourable although acute complications were not infrequent. Procedural complications, which are mainly related to transseptal puncture and device implantation, include air embolism, pericardial effusions/tamponade and device embolization. Knowledge of nature, management and prevention of complications should minimize the risk of complications and allow transcatheter left atrial appendage closure to emerge as a therapeutic option for patients with atrial fibrillation at risk for cardioembolic stroke.

关键词： Atrial fibrillation Stroke prevention Left atrial appendage WATCHMAN device Complications

A note on a boundary condition for spouted beds

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Particuology 2010年第6期8卷 536-538页

作者： norman Epstein Department of Chemical&Biological Engineering The University of British Columbia2216 Main MallVancouverB.C.Canada V6T 1Z3

The boundary condition, zero solids pressure at the top of a particle bed of maximum spoutable height, Hm, is shown to eliminate any resort to empiricism in the derivation of the fluid velocity in the annulus of a spouted bed for which both viscous and inertial effects are taken into account. The same boundary condition fails when applied to a spouted bed for which the bed height H 〈 Hm, especially when H 〈 0.8Hm.

关键词： Spouted beds Annulus flow Boundary condition Particle-fluid hydrodynamics

Transitioning from paternalism to empowerment of farmers in lowincome countries: Farming components to systems

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Journal of Integrative Agriculture 2015年第8期14卷 1490-1499页

作者： David norman Agricultural Economics Department Kansas State University

Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution（i.e., in more heterogeneous and less favourable production environments） areas in low-income countries is followed by a discussion of their *** phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and *** enabled/facilitated the evolutionary ***, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach（i.e., descriptive, diagnosis, testing/evaluation and finally dissemination）, much still needs to be *** leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable *** the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers＇ intimate involvement in their identification, evaluation and *** in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders（i.e., farmers, scientists, extension workers, input/output service providers and policymakers）.Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research（i.e., CGIAR） *** paper concludes with a short discussion on the potential role of formal modelling.

关键词： farming systems research farmer empowerment farmer participatory approaches/techniques globalisation commercialisation conservat

Speciation:genomic sequence data and the biogeography of speciation

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National Science Review 2022年第12期9卷 13-14页

作者： norman A.Johnson Department of Biology University of Massachusetts–Amherst

Two papers in this issue show how the use of genomic sequence data can illuminate the biogeography of the speciation ***,I provide a backdrop to these studies,with a brief history of the use of markers and the biogeog... 详细信息

关键词： Speciation:genomic sequence data and the biogeography of speciation

AN ANALYSIS oF THE SHEAR FAILURE OF RIGID-LINEAR HARDENING BEAMS UNDER IMPULSIVE LOADING

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Acta Mechanica Sinica 1996年第4期12卷 338-348页

作者：王礼立 norman Jones Ningbo University Ningbo 315211China and also University of Science and Technology of ChinaHefei 230026China Impact Research Centre Department of Mechanical EngineeringUniversity of Liverpool.P.O.Box 147Liverpool L69 3BXU.K.

A theoretical rigid-plastic analysis for the dynamic shear failure of beams under impulsive loading is presented when using a travelling plastic shear hinge model which tabes into account material strain hardening. The maximum dynamic shear strain and shear strain-rate can be predicted in addition to the permanent transverse deflections and other parameters. The conditions for the three modes of shear failure, i.e., excess deflection failure, excess shear strain failure and adiabatic shear failure are analyzed. The special case of an infinitesimally small plastic zone is discussed and compared with Nonaka's solution for a rigid, perfectly plastic material. The results can also be generalized to examine the dynamic response of fibre-reinforced beams.

关键词： shear failure rigid-linear hardening plastic beam dynamic response impulsive loading adiabatic shear

Accuracy assessment of real-time kinematics(RTK)measurements on unmanned aerial vehicles(UAV)for direct geo-referencing

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Geo-Spatial Information Science 2020年第2期23卷 165-181页

作者： Desta Ekaso Francesco Nex norman Kerle Department of Earth Systems Analysis ITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe NetherlandsDepartment of Earth Systems AnalysisITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe NetherlandsDepartment of Earth Systems AnalysisITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe Netherlands

Geospatial information acquired with Unmanned Aerial Vehicles(UAV)provides valuable decision-making support in many different domains,and technological advances coincide with a demand for ever more sophisticated data *** consequence is a research and development focus on more accurately referenced images and derivatives,which has long been a weakness especially of low to medium cost UAV systems equipped with relatively inexpensive inertial measurement unit(IMU)and Global Navigation Satellite System(GNSS)*** research evaluates the positional accuracy of the real-time kinematics(RTK)GNSS on the DJI Matrice 600 Pro,one of the first available and widely used UAVs with potentially surveying-grade *** a very high positional accuracy of the drone itself of 2 to 3 cm is claimed by DJI,the actual accuracy of the drone RTK for positioning the images and for using it for mapping purposes without additional ground control is not *** begin with,the actual GNSS RTK position of reference center(the physical point on the antenna)on the drone is not indicated,and uncertainty regarding this also exists among the professional user *** this study the reference center was determined through a set of experiments using the dual frequency static Leica GNSS with RTK *** RTK positioning data from the drone were then used for direct georeferencing,and its results were *** flights were carried out over a 70 x 70 m area with an altitude of 40 m above the ground,with a ground sampling distance of 1.3 *** against ground control points,the planimetric accuracy of direct georeferencing for the photogrammetric product ranged between 30 and 60 *** of direct georeferencing results showed a time delay of up to 0.28 seconds between the drone GNSS RTK and camera image acquisition affecting direct georeferencing results.

关键词： UAV GNSS RTK direct georeferencing aerial triangulation lever arm offset

A fusion at the root of prostate cancer

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Asian Journal of Andrology 2013年第5期15卷 592-593页

作者： norman J Maitland YCR Cancer Research Unit Dept of Biology Universityof York York Y010 5DD UK

Many hematopoietic malignancies have oncogenic gene fusions, like BCR-ABL, in their tumor-initiating cells. This implicates the product of the fusion as a powerful cancer-initiating event. In human prostate cancers, d... 详细信息

关键词： A fusion the root prostate cancer

Operational Wave Now- and Forecast in the German Bight as a Basis for the Assessment of Wave-Induced Hydrodynamic Loads on Coastal Dikes

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Journal of Ocean University of China 2017年第6期16卷 991-997页

作者： DREIER norman FROHLE Peter Institute of River and Coastal Engineering Hamburg University of Technology Hamburg Germany

The knowledge of the wave-induced hydrodynamic loads on coastal dikes including their temporal and spatial resolution on the dike in combination with actual water levels is of crucial importance of any risk-based early warning system. As a basis for the assessment of the wave-induced hydrodynamic loads, an operational wave now-and forecast system is set up that consists of i) available field measurements from the federal and local authorities and ii) data from numerical simulation of waves in the German Bight using the SWAN wave model. In this study, results of the hindcast of deep water wave conditions during the winter storm on 5–6 December, 2013(German name ‘Xaver') are shown and compared with available measurements. Moreover field measurements of wave run-up from the local authorities at a sea dike on the German North Sea Island of Pellworm are presented and compared against calculated wave run-up using the Eur Otop(2016) approach.

关键词： German Bight North Sea wave forecast Cosmo-Model SWAN hydrodynamic loads wave run-up EurOtop

Organic Gases in Fluid Inclusions of Ore Minerals and Their Constraints on Ore Genesis:A Case Study of the Changkeng Au-Ag Deposit,Guangdong,China

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 86-94页

作者： DavidI.norman Department of Earth & Environmental Sciences New Mexico Institute of Mining and Technology (NMT) Socorro NM87801 USA

The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from theChangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C_(1-4) and unsaturatedalkenes C_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg C, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic *** on the compositions of organic gases in fluid inclusions, the authors infer that the Changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the Changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belon

关键词： ore mineral fluid inclusion organic gas Changkeng Au-Ag deposit

Towards social behavior in virtual-agent navigation

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Science China(Information Sciences) 2016年第11期59卷 16-32页

作者： Angelos KREMYZAS norman JAKLIN Roland GERAERTS Department of Information and Computing Sciences Utrecht University

We present Social Groups and Navigation(SGN), a method to simulate the walking behavior of small pedestrian groups in virtual environments. SGN is the first method to simulate group behavior on both global and local levels of an underlying planning hierarchy. We define quantitative metrics to measure the coherence and the sociality of a group based on existing empirical data of real crowds. SGN does not explicitly model coherent and social formations, but it lets such formations emerge from simple geometric rules. In addition to a previous version, SGN also handles group-splitting to smaller groups throughout navigation as well as social sub-group behavior whenever a group has to temporarily split up to re-establish its coherence. For groups of four, SGN generates between 13% and 53% more socially-friendly behavior than previous methods, measured over the lifetime of a group in the simulation. For groups of three, the gain is between 15% and 31%, and for groups of two, the gain is between 1% and 4%. SGN is designed in a flexible way, and it can be integrated into any crowd-simulation framework that handles global path planning and any path following as separate *** show that SGN enables the simulation of thousands of agents in real time.

关键词： virtual humans social-group behavior autonomous agent navigation crowd simulation