1,347 research outputs found

    A systematic approach to multiphysics extensions of finite-element-based micromagnetic simulations: Nmag

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    Extensions of the basic micromagnetic model that include effects such as spin-current interaction, diffusion of thermal energy or anisotropic magnetoresistance are often studied by performing simulations that use case-specific ad-hoc extensions of widely used software packages such as OOMMF or Magpar. We present the novel software framework 'Nmag' that handles specifications of micromagnetic systems at a sufficiently abstract level to enable users with little programming experience to automatically translate a description of a large class of dynamical multifield equations plus a description of the system's geometry into a working simulation. Conceptually, this is a step towards a higher-level abstract notation for classical multifield mutliphysics simulations, similar to the change from assembly language to a higher level human-and-machine-readable formula notation for mathematical terms (FORTRAN) half a century ago. We demonstrate the capability of this approach through two examples, showing 1) a reduced dimensionality model coupling two copies of the micromagnetic sector and 2) the computation of a spatial current density distribution for anisotropic magnetoresistance (AMR). For cross-wise validation purposes, we also show how Nmag compares to the OOMMF and Magpar packages on a selected micromagnetic toy system. We furthermore, briefly discuss the limiations of our framework and related conceptual questions

    Comunidade de morcegos em paisagem natural e alterada no Pantanal da Nhecolândia.

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    Na tentativa de compreender os possíveis efeitos da substituição da vegetação nativa por pastagens exóticas no Pantanal, comparamos a riqueza de espécies e a composição da comunidade de espécies morcegos de uma área pastagem cultivada e de uma área com paisagem relativamente preservada (Fazenda Nhumirim). The attempt to understand the possible effects of the replacement of the native vegetation by cultivated, exotic pastures in the Pantanal, we compared the bat species richness and community composition from an area of cultivated pasture with that of a relatively conserved landscape (Nhumirim ranch)

    Getting Closer or Falling Apart? Euro Area Countries After the Sovereign Debt Crisis

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    We study convergence and divergence dynamics in a sample of euro area countries by assembling an extensive dataset that contains information on public spending and policy outcomes in a variety of areas of government intervention including education, health, and civil justice from the early 1990s. We also focus on other important determinants of a country's economic performance such as the level of regulation of product and labor markets, as well as the trust in political institutions, quality of governance, and inequality. Results show that despite divergent economic growth in the euro periphery countries after the 2010-2012 sovereign debt crisis, the quality of services and level of regulation did not deteriorate or indeed improved, increasing convergence with the core euro countries. However, the euro area sovereign debt crisis dramatically worsened citizens' perceptions of quality of governance, as well as the level of social trust. This calls in question the future political viability of the EMU project and asks for reform

    Analysis of magnetoresistance in arrays of connected nano-rings

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    We study the anisotropic magnetoresistance (AME) of a 2D periodic square array of connected permalloy rings with periodicity of 1m combining experimental and computational techniques. The computational models consists of two parts: 1) the computation of the magnetization and 2) the computation of the current density. For 1), we use standard micromagnetic methods. For 2), we start from a potential difference applied across the sample, compute the resulting electric potential , and subsequently the corresponding current density based on a uniform conductiviy. We take into account the backreaction of the magnetoresistive effects onto the current density by self-consistently computing the current density and conductivity until they converge. We compare the experimentally measured AMR insight into the characteristics of the AMR data. Finally, we demonstrate the importance of taking into account the spatial variation of the current density when computing the AMR

    Visualizing cellular heterogeneity by quantifying the dynamics of MAPK activity in live mammalian cells with synthetic fluorescent biosensors.

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    Mitogen-Activated Protein Kinases (MAPKs) control a wide array of cellular functions by transducing extracellular information into defined biological responses. In order to understand how these pathways are regulated, dynamic single cell measurements are highly needed. Fluorescence microscopy is well suited to perform these measurements. However, more dynamic and sensitive biosensors that allow the quantification of signaling activity in living mammalian cells are required. We have engineered a synthetic fluorescent substrate for human MAPKs (ERK, JNK and p38) that relocates from the nucleus to the cytoplasm when phosphorylated by the kinases. We demonstrate that this reporter displays an improved response compared to other relocation biosensors. This assay allows to monitor the heterogeneity in the MAPK response in a population of isogenic cells, revealing pulses of ERK activity upon a physiological EGFR stimulation. We show applicability of this approach to the analysis of multiple cancer cell lines and primary cells as well as its application in vivo to developing tumors. Using this ERK biosensor, dynamic single cell measurements with high temporal resolution can be obtained. These MAPK reporters can be widely applied to the analysis of molecular mechanisms of MAPK signaling in healthy and diseased state, in cell culture assays or in vivo

    Assessment of the fiscal stance appropriate for the euro area in 2019

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    On 18 June 2018, the European Fiscal Board (EFB) has published its assessment of the general orientation of fiscal policy in the euro area. The report concludes that the favourable economic outlook offers a prime opportunity to rebuild fiscal buffers. Especially euro area Member States with a high government debt-to-GDP ratio need to do more than simply accrue the budgetary benefits of the economic expansion. Lest we repeat the mistakes of the past and rob ourselves of room to manoeuvre when the next crisis hits, this is the time to move towards a somewhat restrictive orientation of fiscal policy in the euro area. It is also the time to upgrade the EU's fiscal framework and prepare a capacity for joint stabilisation for the euro area

    A soja e a saúde humana.

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    Soja na prevenção do câncer; Soja na prevenção das doenças cardiovasculares; Soja na prevenção da tensão pré-menstrual e do climatério (menopausa); Soja na prevenção da osteoporose.bitstream/item/57809/1/Documentos-178.pd
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