Browsing by Issue Date, starting with "2006-02"
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- The actual hydrographic network in SW Portugal - an evolutionary perspectivePublication . Rodrigues, Bruno; Veiga-Pires, C.Both intrinsic factors of hidrographic networks (dynamics changes in the internal fluvial model) and extrinsic factors (climate, tectonics, base level), have an influence in the incision of the valleys and in the formation of fluvial terraces.
- Benthic ecology of semi-natural coastal lagoons, in the Ria Formosa (Southern Portugal), Exposed to different water renewal regimesPublication . Gamito, SofiaSeveral studies in semi-natural coastal lagoons in the Ria Formosa lagoonal system have been carried out. These man-made water reservoirs behave as small lagoons with one opening to the tidal channels, which may be intermittent. Because of their size, these reservoirs are ideal sites for ecological studies. Water quality and macrobenthic fauna were analysed in five water reservoirs. All reservoirs received the same incoming water through a tidal channel, but they differed in water renewal regime. Multidimensional Scaling (MDS) and Discriminant Analysis were used to evaluate the similarity among sites, stations and sampling occasions. Different levels of taxonomic resolution (family, large taxonomic groups and phylum level) were also evaluated. The separation of sites and stations became unclear using high taxonomic levels. Results from the multivariate analyses suggest a slight differentiation of the stations according to sampling occasion but a clear differentiation of the several water reservoirs. Some of the lagoons studied with low water renewal rates showed strong environmental variations. They were characterised by low diversity indexes and abundance of small-sized organisms. Other lagoons, with high water renewal rates, showed low environmental variation and well diversified and structured benthic communities. The main environmental factor that seems to affect the benthic communities was the variation in salinity between neap and spring tides, which is related with the water renewal regime. Coastal lagoons offer a protected shallow habitat, which can be highly productive. Well structured communities, controlled by k-strategists, can develop and settle in leaky lagoons, that is, lagoons with wide entrance channels and tidal currents which guarantee a good water renewal. In these lagoons, biomass can accumulate in large organisms. In contrast, lagoons with a single narrow entrance, that may be closed for long periods, are characterised by persistent physical stress and are dominated by communities of small-sized r-strategists.
- Simple and rapid RNA extraction from freeze-dried tissue of brown algae and seagrassesPublication . Pearson, G. A.; Lago-Lestón, Asunción; Valente, M.; Serrão, EsterAn inexpensive and rapid RNA extraction protocol for brown algae and seagrasses is presented, based on homogenization in a simple CTAB buffer and selective precipitation of RNA with lithium chloride. The protocol avoids the use of toxic chaotropic agents and phenol; high concentrations of dithiothreitol are used to inhibit RNase activity and to prevent oxidative cross-linking of nucleic acids by phenolics. A relatively high throughput of about 100 samples in 24 h can be achieved for, for example, Northern analysis. Yields of 50–200 µg g−1 fresh weight are comparable with those obtained for higher plants using commercially available kits. Tests of the extraction procedure demonstrate that high quality, intact RNA can be obtained from a variety of lyophilized brown algal tissues, even after prolonged storage at room temperature. Lyophilization is therefore suggested as an alternative to freezing tissue at −70°C to −80°C. The RNA obtained was used directly in several downstream applications to detect Fucus plastid-encoded transcripts by RNA-labelling, RT-PCR and Northern analysis.
- O desenvolvimento pessoal e profissional do educador de infância e suas implicações junto da criança autistaPublication . Cavaco, Nora Alejandra Pires Almeida; Simões, Maria Helena Ralha; Simões, Carlos MarquesApós contextualizar a investigação, explicitando as motivações que conduziram à escolha do problema em estudo, procura-se indicar os principiais objectivos prosseguidos, elucidando as preocupações que lhe deram origem e à escolha do enquadramento conceptual, bem como às opções metodológicas tomadas, procura-se a partir de uma óptica construtivista e desenvolvimentista, explicitar conceptualmente os principais aspectos relativos aos desenvolvimentos do educador de infância, a nível pessoal e profissional, no sentido de fundamentar os principais conceitos utilizados.
- Diagnóstico social do concelho de São Brás de AlportelPublication . Sousa, Vanessa Duarte de; Biel, Filipa Capelo; Oliveira, NunoO presente documento introduz os principais elementos de diagnóstico social para o concelho de São Brás de Alportel.
- Sistema de informação do concelho de São Brás de AlportelPublication . Sousa, Vanessa Duarte de; Biel, Filipa Capelo; Oliveira, NunoO documento apresenta os resultados da monitorização do território, através de um conjunto de quadros de bordo construídos a partir de um conjunto de dimensões analíticas que nos permitem aferir dos múltiplos elementos de diagnóstico social do concelho de São Brás de Alportel.
- Fonseca Domingos, um progressista poeta do povoPublication . Mesquita, José Carlos VilhenaFonseca Domingos era um republicano convicto, um admirador do jacobinismo revolucionário, e um entusiasta dos movimentos libertadores do proletariado. O seu carácter revolucionário, justo e interventivo, refletia-se nos seus escritos literários. Como poeta era exímio no soneto, sendo certo que embora cultivando a poesia clássica nunca foi um arcádico. Depois bivaqueou na prosa, escrevendo alguns contos de belo efeito humanístico e de grande pujança literária. O seu estilo oscila entre o neo-realismo e o pós-modernismo, inspirados na denúncia da exploração humana, nos conflitos sociais das classes produtivas, no dilema entre a verdade e o interesse, a cobiça e a inveja.