Encontrados 11 documentos, a visualizar página 1 de 2

External school evaluation in Portugal: a glance at the impacts on curricular a...

Strictly non-blocking all-optical-cross-connect demonstrator for WDM wavelength...

In this paper, we assess the design and performances of a strictly non-blocking all-optical cross-connect demonstrator node for WDM wavelength path networks. The all-optical cross-connect (AOXC) prototype was experimentally tested in a small 2 x 2 WDM network with a STM-16 bit stream per channel. The single and cascaded performance of the AOXC was also simulated and its results were validated with the experimen...

Phenotypic variation of Fucus ceranoides, F. spiralis and F. vesiculosus in a t...

Brown algae includes several species of Fucus, reported both in the tidal and intertidal zones of cold and temperate regions. Environmental parameters induce wide biological variability in intertidal algae, manifested by alterations at several levels, and this has lead to the failure of some reports to discriminate between closely related taxa, particularly Fucus species. As the genus Fucus is widely represente...

Selecção de modelos em amostragem por distâncias

A selecção de um modelo que se ajuste adequadamente a um conjunto de dados é uma parte fulcral no processo da inferência estatística. O critério mais comum para seleccionar uma função de detectabilidade, que se ajuste a um conjunto de dados de distâncias, denomina-se critério de informação de Akaike (AIC). Para avaliar a performance da rotina da selecção de modelos implementada no programa DISTANCE (Thomas et a...

The study of bacterioplankton dynamics in the Berlengas Archipelago (West coast...

The relationship between bacterioplankton and environmental forcing in the Berlengas Archipelago (Western Coast of Portugal) were studied between February 2006 and February 2007 in two sampling stations: Berlenga and Canal, using an HJ-biplot. The HJ-biplot showed a simultaneous display of the three main metabolic groups of bacteria involved in carbon cycling (aerobic heterotrophic bacteria, sulphate-reducing b...

Histological evaluation of the exposure to 3,4-dichloroaniline in the estuarine...

This work presents an experimental approach to test Mesopodopsis slabberi as a potential indicator of pollution. The toxic effects of 3,4-dichloroaniline (DCA) on the histology of this estuarine mysid were studied. After an acclimation period of two days, the mysids were exposed to different sublethal 3,4-DCA concentrations (0.10, 0.30, 0.50, 0.90, 1.00, 1.10, 1.20, 1.30 and 1.40 mg/L), for a period of 48 h. Ea...

Bacterioplankton dynamics in the Mondego estuary (Portugal)

In this work, the density of bacterioplankton and environmental parameters were monitored over a 11 month period (July 1999-June 2000), and also during one tidal cycle (15 June 2000), at two sampling stations, in the estuary of River Mondego. These data were treated by multivariate analyses methods in order to identify the key factors that control the dynamics of the bacterioplankton in the estuary. Bacterial d...

Histochemistry and histology in planktonic ecophysiological processes determina...

Zooplankton communities in temperate climates exhibit well documented seasonal variability. The reasons proposed to explain this kind of behaviour range from the effect of physical-chemical conditions (salinity, nutrients, temperature) growth rates, mortality, migration rates, food availability and predation. It is noticeable that the majority of the factors mentioned are external to the organisms, being enviro...

A evolução de conceitos entre as declarações de Santiago e de Caracas (texto4)

Cadernos de Sociomuseologia Centro de Estudos de Sociomuseologia

Sarcoidosis of the central nervous system and skeletal muscles.