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Evolutionary history and population genetics of a cyprinid fish (Iberochondrost...

Abstract The use of molecular techniques has shown that hybridization and introgression have significant impacts in evolution, by means of transfer of genetic variation and formation of hybrid species. In this paper we use mitochondrial and nuclear sequence data to investigate the evolutionary history, levels of genetic diversity and population differentiation of a rare and endangered fish species. Our results ...

Temporal changes in macrofauna as response indicator to potential human pressur...

Sandy beaches are natural dynamic ecosystems, which are becoming worldwide increasingly disturbed by intensive human direct use, coastal development and erosive evolution. In this study, we have examined whether ten years of potential increased human pressures have resulted in significant changes in the macrofaunal assemblages’ structure and composition of two mesotidal sandy beaches (Cabedelo – urban beach, an...

Implementing the SC-FDMA transmission technique using the GNURadio platform

Dissertação apresentada para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Clinical, physical and lifestyle variables and relationship with cognition and ...

It is relevant to unravel the factors that may mediate the cognitive decline observed during aging. Previous reports indicate that education has a positive influence on cognitive performance, while age, female gender and, especially, depressed mood were associated with poorer performances across multiple cognitive dimensions (memory and general executive function). Herein, the present study aimed to characteriz...

Background EEG activity of epileptic patients: search of relations between diff...

The clinical classification of focal epileptic patients depends greatly on the fuci localization and is determinant to the correct choice of therapy. Consequently, the well-being of the patient is also dependent on the foci localization methodology used in each case. (...)Keywords: epilepsy; epilptogenic foci localization; background activity of th eeg; non linear association methods; multimedia informatio...

KNICKPOINTS TRANSITÓRIOS E PERFIS RELÍQUIA EM AFLUENTES DOS RIOS TEJO E ZÊZERE ...

ABSTRACT Several tributaries of the Tejo and Zêzere rivers show a graded relict profile in the most upstream reach and a rejuvenated profile in the lower reach. A major slope break in the long profile (knickpoint) separates both reaches. Extrapolation of the oldest graded relict profile downstream to the confluence allowed the incision amount to be quantified. Results reveal that the downcutting is higher in st...

A IDENTIFICAÇÃO AUTOMÁTICA DE KNICKPOINTS NAS BACIAS DOS RIOS POIO E CABRIL (BA...

RESUMO Rápidos e quedas de água, designados na literatura especializada por knickpoints (Kps), constituem usualmente a expressão geomorfológica no leito do rio, do atravessamento de litologias mais resistentes, da exploração de descontinuidades estruturais, ou o resultado do abaixamento do nível de base, cujo sinal é transmitido para montante através de 'vagas de erosão' no perfil longitudinal. Por este motivo,...

Somalia as a market for private military and security companies: definitions, a...

The current academic debate around private military and security companies (PMSCs) is intense and without consensus, starting with definitions. There is still no agreement on the question of what a PMSC is. In order to establish a comprehensive conceptual framework, this study examined the different definitions and identified divergences and convergences. This allowed us to propose definitions in order to contr...

Cenozóico das bacias do Douro (sector ocidental), Mondego, Baixo Tejo e Alvalade

Typological classification of clayey raw materials for ceramics manufacture, in...

Mapping of clay resources in the Cenozoic deposits of the Tábua region (central Portugal) has been carried out, together with the chemical, mineralogical and technological characterization of seventeen clay samples. The study was undertaken to relate the lithostratigraphic units and the typology of raw materials with regard to the manufacture of ceramics. The sedimentary succession comprises two units with di...