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GPS tracking of non-breeding ravens reveals the importance of anthropogenic food sources during their dispersal in the Eastern Alps

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Current Zoology 2016年第4期62卷 337-344页

作者： Matthias-claudio LORETTO Richard SCHUSTER Thomas BUGNYAR Department of Cognitive Biology University of Vienna Althanstrasse 14 A-1090 vienna Konrad Lorenz Forschungsstelle Core Facility for Behaviour and Cognition University of Vienna Fischerau 11 A-4645 GrLinau im Almtal Austria CDepartment of Forest and Conservation Sciences University of British Columbia Vancouver B.C. Canada V6T1Z4

In many songbirds, the space use of breeders is well studied but poorly understood for non-breeders. In common ravens, some studies of non-breeders indicate high vagrancy with large individual differences in home range size, whereas others show that up to 40% of marked non-breeders can be regularly observed at the same anthropogenic food source over months to years. The aim of this study was to provide new insights on ravens＇ behavior during dispersal in the Eastern Alps. We deployed Global Positioning System （GPS） loggers on 10 individuals to gather accurate spatial and temporal information on their movements to quantify： 1） the dimension of the birds＇ space use （home range size with seasonal effects and daily/long-term travel distances）, 2） how long they stayed in a dispersal stage of wandering as opposed to settling temporarily, and 3） their destination of movements. We recorded movements of up to 40km per hour, more than 160km within 1 day and more than 11,000 km within 20 months, indicating high vagrancy. Switching frequently between temporarily settling and travelling large distances in short time intervals leads to extensive home ranges, which also explains and com- bines the different findings in the literature. The destinations are rich anthropogenic food sources, where the birds spent on average 75% of their time. We discuss how ravens may find these ＂feeding hot spots＂ and which factors may influence their decision to stay/leave a site. The strong dependence on anthropogenic resources found in this population may have implications for site management and conservation issues.

关键词： common raven Corvus corax non-breeder space use dispersal kernel density.

Marine propellers performance and flow-field prediction by a free-wake panel method

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Journal of Hydrodynamics 2014年第5期26卷 780-795页

作者： GRECO Luca MUSCARI Roberto TESTA claudio DI MASCIO Andrea CNR-INSEAN Italian Ship Model BasinRomeItaly CNR-IAC Istituto per le Applicazioni del Calcolo "M. Picone"RomeItaly

A Boundary Element Method （BEM） hydrodynamics combined with a flow-alignment technique to evaluate blades shed vorticity is presented and applied to a marine propeller in open water. Potentialities and drawbacks of this approach in capturing propeller performance, slipstream velocities, blade pressure distribution and pressure disturbance in the flow-field are highlighted by comparisons with available experiments and RANSE results. In particular, correlations between the shape of the convected vortex- sheet and the accuracy of BEM results are discussed throughout the paper. To this aim, the analysis of propeller thrust and torque is the starting point towards a detailed discussion on the capability of a 3-D free-wake BEM hydrodynamic approach to describe the local features of the flow-field behind the propeller disk, in view of applications to propulsive configurations where the shed wake plays a dominant role.

关键词： BEM hydrodynamics free-wake analysis BEM-RANSE comparison

Using remote sensing to assess impacts of land management policies in the Ordos rangelands in China

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International Journal of Digital Earth 2013年第S2期6卷 81-102页

作者： Weicheng Wu Eddy De Pauw claudio Zucca International Center for Agricultural Research in Dry Areas(ICARDA)/CGIAR AmmanJordan Pedology and Land Degradation Department of Agriculture and Desertification Research Group(NRD)University of Sassari07100 SassariItaly

Implementation of land management policies influences land use and hence causes environmental *** the Ordos rangelands in China as a case study,this paper explores the potential of remote sensing to assess in dryland areas the impacts of policies on the *** Landsat images of the period 19782010 were acquired and those corresponding to the starting dates of implementation of different policies were selected for land-cover change analysis;others were used to check the detected change and track the normalized difference vegetation index(NDVI)trajectory matched with time series of meteorological data for calibration of natural response of rangelands to *** results indicate that policy impacts are complex and include both positive and negative aspects depending on the locality in *** one hand,policies have aroused the enthusiasm of people in agricultural production and sandcontrol leading to the recovery of about 2618 km2 of desertified rangeland and sandy land,and economic growth,on the other hand,provoked vegetation degradation with an accumulated area of 2439 km2 when policies cannot reconcile the conflict between environmental protection and the interest of rural ***,degradation is not absolute and can be mitigated by the implementation of rational policies.

关键词： land use/cover change multi-temporal remote sensing human intervention spatial variability NDVI trajectory

Numerical Solution of Partial Differential Equations in Random Domains:An Application to Wind Engineering

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Communications in Computational Physics 2009年第2期5卷 515-531页

作者： claudio Canuto Davide Fransos Dipartimento di Matematica Politecnico di TorinoC.so Duca degli Abruzzi 2410129 TorinoItaly

An application of recent uncertainty quantification techniques to Wind Engineering is *** particular,the study of the effects of small geometric changes in the Sunshine Skyway Bridge deck on its aerodynamic behavior is *** results in the numerical solution of a proper PDE posed in a domain affected by randomness,which is handled through a mapping approach.A non-intrusive Polynomial Chaos expansion allows to transform the stochastic problem into a deterministic one,in which a commercial code is used as a black-box for the solution of a number of Reynolds-Averaged Navier-Stokes *** use of proper Gauss-Patterson nested quadrature formulas with respect to a Truncated Weibull probability density function permits to limit the number of these computationally expensive simulations,though maintaining a sufficient *** Chaos approximations,statistical moments and probability density functions of time-independent quantities of interest for the engineering applications are obtained.

关键词： Uncertainty quantification stochastic partial differential equations random domains mapping approach polynomial chaos wind engineering

A Novel Cu–GNPs Nanocomposite with Improved Thermal and Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 148-152页

作者： Abdollah Saboori Matteo Pavese claudio Badini Paolo Fino Department of Applied Science and Technology Politecnico di Torino

Classical powder metallurgy followed by either hot isostatic pressing（HIPing） or repressing–annealing process was used to produce Cu–graphene nanoplatelets（GNPs） nanocomposites in this work. A wet mixing method was used to disperse the graphene within the matrix. The results show that a uniform dispersion of GNPs at low graphene contents could be achieved, whereas agglomeration of graphene was revealed at higher graphene contents. Density evaluations showed that the relative density of pure copper and copper composites increased by using the post-processing ***, it should be noticed that the efficiency of HIPing was remarkably higher than repressing–annealing process, and through the HIPing, fully dense samples were achieved. The Vickers hardness results showed that the reconsolidation steps can improve the mechanical strength of the specimens up to 50% owing to the progressive porosity elimination after reconsolidation. The thermal conductivity results of pure copper and composites at high temperatures showed that the postprocessing techniques could enhance the conductivity of materials significantly.

关键词： Copper Graphene nanoplatelets (GNPs) Powder metallurgy Hot isostatic pressing Thermal conductivity

Overburden management in open pits: options and limits in large limestone quarries

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International Journal of Mining Science and Technology 2019年第2期29卷 217-228页

作者： claudio Oggeri Taddeo Maria Fenoglio Alberto Godio Raffaele Vinai Department of Environment Land and Infrastructure Engineering Politecnico di Torino College of Engineering Mathematics and Physical Sciences University of Exeter

The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important factors affecting the disposal phase. Economic and environmental requirements must be followed in order to achieve the best reclamation results, keeping into account site constraints such as slope stability, hauling and dumping issues, and interactions with groundwater. This paper deals with the above mentioned issues, illustrating a rational approach applied on the case of a large limestone quarry where the thickness of the overburden is relevant and the spoil material has to be dumped in a flooded pit. The proposed multidisciplinary approach led to the selection of most suitable methods for excavation, transportation and disposal. The selection was based on a detailed laboratory and site characterisation that defined favorable and adverse factors to be considered during the preliminary study of a large quarrying project.

关键词： Open pit Overburden Soil testing Limestone quarry Muck On-site testing

Closed and Open Metabolic Cycles: Transition Time

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Journal of Biomedical Science and Engineering 2016年第2期9卷 127-140页

作者： Antonio sillero Víctor García-Herrero Departamento de Bioquímica Facultad de Medicina Instituto de Investigaciones Biomédicas Alberto Sols UAM/CSIC Madrid Spain

A metabolic cycle can be viewed as a central core and its branches. The central core is here firstly considered as a pre-closed metabolic cycle (CMC), with a unique first substrate, but with no input or output of other components. By contrast, the metabolic cycles in nature are open metabolic cycles (OMC) with output and input of external substrates (through “metabolic branches”), modulating continuously the enzyme activities and the total concentration of their substrates thorough complex regulatory phenomena. In this work, the transition from a Closed to an Open metabolic cycle has been simulated by a consecutive entry and exit of two components through the catalytic action of two enzymes. It is known that after any alteration of the initial conditions, the cycles need a time to reach new equilibrium. We have measured the changes of transition time (T.T.) values in 81 models of CMC differing in Km or Vmax values. In general, the T.T. tends to be shorter in cycles with preponderant lower Km and higher Vmax values. Further, Mathematica refinement for the estimation of transition time from the data previously calculated can be obtained with the use of the command Interpolating Function.

关键词： Metabolic Cycles Equilibration Times Kinetic Constants Differential Equations Mathematica

Modulation of the magnetic properties of gold-spinel ferrite heterostructured nanocrystals

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Nano Research 2020年第3期13卷 785-794页

作者： Elvira Fantechi Claudia Innocenti Giovanni Bertoni claudio Sangregorio Francesco Pineider INSTM and Dept of Chemistry and Industrial ChemistryUniversity of PisaPisa 56124Italy ICCOM-CNR Institute for the Chemistry of OrganoMetallic CompoundsSesto Fiorentino 50019Italy INSTM and Dept of Chemistry aU.Schiffnt University of FlorenceSesto Fiorentino 50019Italy IMEM-CNR Institute of Materials for Electronics and MagnetismParma 43124Italy CNR-Istituto Nanoscienze Modena 41125Italy

The rational design of complex nanostructures is of paramount importance to gain control over their chemical and physical ***,magnetic-plasmonic heterostructured nanocrystals have been recognized as key players in nanomedicine as multifunctional therapeutic-diagnostic tools and in *** we show how the properties of gold-iron oxide heterostructured nanocrystals can be tuned by chemical doping of the magnetic *** divalent cations in the iron oxide were substituted with cobalt and manganese to obtain a general formula Au-MFe2O4(M=Fe,Co,Mn).Magnetic properties of the heterostructures could be tuned,while maintaining well-defined plasmon resonance signatures,confirming the dual magnetic-plasmonic functional capability of these nanostructures.

关键词： heterostructured nanocrystals seeded-growth spinel ferrites magnetic-plasmonic nanoparticles

Metabolic Cycles: Effect of a Simultaneous Input and Output of Two Substrates

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Journal of Biomedical Science and Engineering 2016年第13期9卷 624-637页

作者： Antonio sillero Víctor García-Herrero Departamento de Bioquí mica Facultad de Medicina Instituto de Investigaciones Biomédicas Alberto Sols (UAM/CSIC) Arzobispo Morcillo Madrid Spain

The metabolic cycle firstly considered here is composed of a unique initial substrate, six enzymes, and five empty boxes to accommodate the substrates derived from the transformation of the initial substrate. This cycle was considered as a pre-Closed Metabolic Cycle (CMC). Using this model, the influence of changing the kinetic constant values of any enzyme on the substrate concentration was explored. This model was transformed into an open metabolic cycle (OMC) by the input and output of two metabolites catalyzed by two external enzymes. In this case, the relative rates of input and output of metabolites were also examined;it can be concluded that the OMC cycles form delicate and fragile structures which can be theoretically disrupted, making them metabolically unfeasible.

关键词： Metabolic Cycles Metabolic Regulation Kinetic Constants Differential Equations Metabolites: Input and Output