Top quark production at the LHC

Twenty years past its discovery, the top quark continues attracting great interest as experiments keep unveiling its properties. An overview of the latest measurements in the domain of top quark production, performed by the ATLAS and CMS experiments at the CERN LHC, is given. The latest measurements of top quark production rates via strong and electroweak processes are reported and compared to different perturbative QCD predictions. Fundamental properties, such as the mass or the couplings of the top quark, as well as re-interpretations seeking for beyond the standard model contributions in the top quark sector, are extracted from these measurements. In each case an attempt to highlight the first results and main prospects for the on-going Run 2 of the LHC is made.Comment: Contribution to the proceedings of the 50th Rencontres de Moriond Electroweak session - 201

Structural Flyby Characterization of Nanoporosity

Recently, Ferreira da Silva et al. [3] have performed a gradient pattern analysis of a canonical sample set (CSS) of scanning force microscopy (SFM) images of p-Si. They applied the so-called Gradient Pattern Analysis to images of three typical p-Si samples distinguished by different absorption energy levels and aspect ratios. Taking into account the measures of spatial asymmetric fluctuations they interpreted the global porosity not only in terms of the amount of roughness, but rather in terms of the structural complexity (e.g., walls and fine structures as slots). This analysis has been adapted in order to operate in a OpenGL flyby environment (the StrFB code), whose application give the numerical characterization of the structure during the flyby real time. Using this analysis we compare the levels of asymmetric fragmentation of active porosity related to different materials as p-Si and "porous diamond-like" carbon. In summary we have shown that the gradient pattern analysis technique in a flyby environment is a reliable sensitive method to investigate, qualitatively and quantitatively, the complex morphology of active nanostructures

SOCIAL EXCHANGE RATES, MERCOSUR AND ECONOMIC DEVELOPMENT

The path towards a common market requires an alignment of macroeconomic policies. In the case of the MERCOSUL member countries, the observed disparities in the exchange, tax and monetary policies constitute major imbalances and impede future international economic integration. Apart from residual differences on trade policies among the member countries, macroeconomic policy disparities also reflect populism and the resulting lack of political will and mutual commitment with the regional goals. There is general professional agreement that, under a fixed exchange rate regimen with trade protection, the social exchange rate exceeds the official and/or market rate. Accordingly, the adoption of an exchange regimen with flexible exchange rates certeris paribus should significantly reduce the difference between the official exchange or market rate and the social exchange rate. The general purpose of this paper is to evaluate the impact of the changes of exchange policies in Brazil against the backdrop of the MERCOSUR economic integration process. To do this, an appropriate measure for the social exchange rate is developed and estimated. This measure also has an immediate practical relevance, as it is suitable for use in the economic analysis of investment projects in Brazil. By using a model of opportunity cost for foreign exchange to estimate the social exchange rate, the study concludes that there was no relevant alteration in the order of economic activities according to the degree of effective protection. The exchange policy changes effects will only be felt in the medium and long run, but their reflections can already be clearly perceived through the declining tendency of the social exchange rate.International Development, International Relations/Trade,

Molecular analysis of anterior endoderm during Xenopus development: a funtional and genomic approach

Tese de doutoramento em Biologia (Biologia do Desenvolvimento), apresentada à Universidade de Lisboa através da Faculdade de Ciências, 2008Fundação para a Ciência e Tecnologia (FCT), (SFHR/BD/10035/2002