Chronic Reboxetine Desensitizes Terminal but not Somatodendritic α2-Adrenoceptors Controlling Noradrenaline Release in the Rat Dorsal Hippocampus

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Lessons from April 6, 2009 L'Aquila earthquake to enhance microzoning studies in near-field urban areas

AbstractThis study focuses on two weak points of the present procedure to carry out microzoning study in near-field areas: (1) the Ground Motion Prediction Equations (GMPEs), commonly used in the reference seismic hazard (RSH) assessment; (2) the ambient noise measurements to define the natural frequency of the near surface soils and the bedrock depth. The limitations of these approaches will be discussed throughout the paper based on the worldwide and Italian experiences performed after the 2009 L'Aquila earthquake and then confirmed by the most recent 2012 Emilia Romagna earthquake and the 2016–17 Central Italy seismic sequence. The critical issues faced are (A) the high variability of peak ground acceleration (PGA) values within the first 20–30 km far from the source which are not robustly interpolated by the GMPEs, (B) at the level 1 microzoning activity, the soil seismic response under strong motion shaking is characterized by microtremors' horizontal to vertical spectral ratios (HVSR) according to Nakamura's method. This latter technique is commonly applied not being fully compliant with the rules fixed by European scientists in 2004, after a 3-year project named Site EffectS assessment using AMbient Excitations (SESAME). Hereinafter, some "best practices" from recent Italian and International experiences of seismic hazard estimation and microzonation studies are reported in order to put forward two proposals: (a) to formulate site-specific GMPEs in near-field areas in terms of PGA and (b) to record microtremor measurements following accurately the SESAME advice in order to get robust and repeatable HVSR values and to limit their use to those geological contests that are actually horizontally layered

Second Order ADER Scheme for Unsteady Advection-Diffusion on Moving Overset Grids with a Compact Transmission Condition

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Second order ADER scheme for advection-diffusion on moving overset grids with a compact transmission condition

We propose a space-time Finite Volume scheme on moving Chimera grids for a general advection-diffusion problem. Special care is devoted to grid overlapping zones in order to devise a compact and accurate discretization stencil to exchange information between different mesh patches. Like in the ADER method, the equations are discretized on a space-time slab. Thus, instead of time-dependent spatial transmission conditions between relatively moving grid blocks, we define interpolation polynomials on arbitrarily intersecting space-time cells at the block boundaries. \rtwo{Through this scheme, a mesh-free FEM-predictor/FVM-corrector approach is employed for representing the solution.} In this discretization framework, a new space-time Local Lax-Friederichs (LLF) stabilization speed is defined by considering both the advective and diffusive nature of the equation. The numerical illustrations for linear and non-linear systems show that background and foreground moving meshes do not introduce spurious perturbation to the solution, uniformly reaching second order accuracy in space and time. Finally, it is shown that several foreground meshes, possibly overlapping and with independent displacements, can be employed thanks to this approach

ADER scheme for incompressible Navier-Stokes equations on Overset grids with a compact transmission condition

A space-time Finite Volume method is devised to simulate incompressible viscous flows in an evolving domain. Inspired by the ADER method, the Navier-Stokes equations are discretized onto a space-time overset grid which is able to take into account both the shape of a possibly moving object and the evolution of the domain. A compact transmission condition is employed in order to mutually exchange information from one mesh to the other. The resulting method is second order accurate in space and time for both velocity and pressure. The accuracy and efficiency of the method are tested through reference simulations.Une méthode des volumes finis spatio-temporels est conçue pour simuler des écoulements visqueux incompressibles dans un domaine évolutif. Inspirée de la méthode ADER, les équations de Navier-Stokes sont discrétisées sur un maillage spatio-temporel overset qui est capable de prendre en compte à la fois la forme d’un objet éventuellement en mouvement et l’évolution du domaine. Une condition de transmission compacte est employée afin d’échanger mutuellement des informations d’un maillage à l’autre. La méthode résultante est d’une précision de second ordre dans l’espace et dans le temps pour la vitesse et la pression. La précision et l’efficacité de la méthode sont testées sur des cas test pris de la littérature

Paleomagnetism of the Penatecaua magmatism: The CAMP intrusive rocks in the Amazonas Basin, northern Brazil

The Penatecaua magmatism (~201 Ma) is part of the Central Atlantic Magmatic Province (CAMP) and is represented by voluminous sills in the Amazonas Basin, north Brazil. The sills appear south of the Amazonas River, particularly in the Medicilândia, Placas, and Rurópolis cities. To the north of the river, near Monte Alegre and Alenquer, smaller sills and NNE-SSW dikes prevail. Paleomagnetic data from 28 sampling sites of sills and dikes from all areas gave consistent results of normal polarity. Despite the large area of occurrence, the VGPs show small dispersion, consistent with a very brief emplacement time, as indicated by the radiometric ages. However, some sites, mainly from Alenquer and the southern sills, gave anomalous directions that may represent the record of a transitional geomagnetic field. The calculated paleomagnetic pole includes former data from Guerreiro and Schult (1986) plotting at 260.1°E 77.5°S (N = 30; A95 = 3.8°; k = 48) and agrees with other high-quality CAMP poles for South America

Climatic and anthropogenic factors explain the variability of Fagus sylvatica treeline elevation in fifteen mountain groups across the Apennines

Abstract Background Fagus sylvatica forms the treeline across the Apennines mountain range, with an average elevation of 1589 m a.s.l. Previous studies evidenced that the current position of the treeline in the Apennines is heavily depressed as a result of a complex interaction between climatic factors and the past human pressure. In this study we correlated treeline elevation in the fifteen major mountain groups in the Apennines with selected climatic, geomorphological, and human disturbance variables in order to investigate in detail the site-specific features affecting the current treeline distribution. Results Treeline elevation was lowest in the North Italy (Apuan Alps), while the highest treeline was found in Central Italy (Simbruini). An absolute maximum treeline elevation of F. sylvatica exceeding 2000 m a.s.l. was found on 13 mountain peaks in Central and Southern Italy. Noteworthy, treeline elevation was largely lower on warmer south-facing slopes compared to northern slopes, with values several hundred meters lower in the Gran Sasso and Velino-Sirente. Although the causes of this pattern are still unknown, we argue that treeline elevation on south-facing slopes may be limited by the combination of climatic constraints (i.e. summer drought) and human disturbance. Evidence of a pervasive anthropogenic effect depressing treeline elevation was found in the North (Apuan Alps) Central (Gran Sasso, Velino-Sirente, Sibillini) and Southern part of Apennines (Pollino). By contrast, treeline elevation of the Laga, Simbruini, and Orsomarso mountain groups appears less affected by past anthropogenic disturbance. Finally, we recorded in the several mountain groups (i.e. Majella, Marsicani and Pollino) the coexistence of very depressed treelines just a few kilometers away from much higher treelines, among the highest ever recorded for F. sylvatica. Conclusions Finally, we argue that F. sylvatica treeline across the Apennines is locally shaped both by the interaction of low temperatures experienced by the species in its earliest life stages in snow-free open spaces with summer soil water depletion and human disturbance