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Variable within-brood maternal provisioning in newly extruded embryos of Homaru...

Offspring quality of decapod crustaceans has been widely studied, with special emphasis on the sources of variability determining embryonic and larval quality. Nevertheless, maternal provisioning has commonly been overlooked as a potential source of offspring within-brood variability. In the present study, the existence of variable maternal provisioning was assessed through the analysis of the fatty acid (FA) p...

Filtragem de ruído speckle em imagens clínicas de ecografia

A ecografia assume-se como uma ferramenta de diagnóstico importante e frequentemente usada pelo facto de ser um meio económico, dinâmico, aliado à sua natureza não invasiva e não ionizante. No entanto, uma das suas principais deficiências é a baixa qualidade das imagens, devido à presença de ruído speckle, que para além de afetar o contraste da imagem pode, em certos casos, adicionar detalhes espúrios ou mascar...

Ferramenta computacional para o dimensionamento de estruturas laminares de betã...

Tese de mestrado integrado. Engenharia Civil (Estruturas). Universidade do Porto. Faculdade de Engenharia. 2010

Influence of seismic activity in the atmospheric electrical field in Lisbon (Po...

The atmospheric electric field (AEF) can be influenced by different factors like cosmic radiation, radioactivity and aerosols [1]. Two innovative works have shown the possibility of enhanced air ionization, with consequent AEF perturbations, in the preparatory stage of earthquakes (EQ): Freund et al. [2] base their arguments on charge separation generated in the stressed volume followed by positive charges flow...

Supressão do Campo Eléctrico Atmosférico aquando do sismo de Sousel, M = 4.1

In recent years different phenomena associated with seismic events have been referred in the literature. These include: unusual ultra-low-frequency electromagnetic emissions; anomalies in radio transmissions; variation of the ionosphere total electron content; and anomalous levels of different geochemical elements (in particular radon) in the earthquake preparation zone. Recent works shown the possibility of en...

Heat as by-product or sub-product of CO2 storage in mafic and ultramafic rocks

Exergy cost of mineral resources

Mineral deposits are considered as natural capital whose value can be assessed in exergy terms. Historical industry experience provides evidence that exploitation of mineral deposits and the beneficiation of ores are essentially energy intensive. The persisting decline of the grade of the developed deposits demands increasing exergy replacement and processing costs. The results demonstrate how far processed ore...

Influences of cosmic radiation, artificial radioactivity and aerosol concentrat...

The atmospheric electric field is influenced by cosmic radiation, radioactivity and aerosols. In this work we investigate the existence of: (i) correlations between relative anomalies of annual values of atmospheric electric field and cosmic radiation intensity, artificial radioactivity and aerosol concentration; (ii) seasonal correlations between relative anomalies of the atmospheric electric field and cosmic ...

Role of Sorption Isotherms in the Analysis of Coupled Heat and Mass Fluxes in P...

The aim of this work is to show the importance of the sorption isotherms in the study of the heat and mass fluxes in unsaturated porous media. General forms of the heat and mass fluxes are presented in terms of experimentally accessible quantities. The role of the isotherm slope in the coupling of heat and mass fluxes and its influence on the effective permeability are shown. Separate relations for vapor and li...