Browsing by Issue Date, starting with "2012-09"
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- Miocene to recent rhodoliths of the Azores: systematics, palaeoecology and palaeobiogeographyPublication . Rebelo, Ana C.; Rasser, Michael; Neto, Ana I.; Ávila, Sérgio P.“[…]. The project aims to produce the first taxonomical study of the Late-Miocene-Early Pliocene rhodolith coralline algae for the Azores and to produce check-lists of the rhodolith coralline algae species by Island collected from selected outcrops. The outcrops will be studied geologically, chronostratigraphically and geochronologically in the frame of the project "The Route of the Fossils". Data sets will be used to establish the (palaeo)-biogeographical relationships between the Atlantic archipelagos (Azores, Madeira, Canaries and Cape Verde). The results will be compared with those of other marine organisms (mollusks, echinoderms, littoral fishes, bryozoans, ostracods). […]”
- Um pouco de história da visualização de dadosPublication . Silva, Osvaldo; Sousa, Áurea[…] Nesta comunicação, são referidos os principais marcos históricos da visualização no âmbito da análise de dados, enfatizando-se as principais técnicas de visualização e as influências de algumas personalidades, que contribuíram para o seu desenvolvimento.
- Phylogeography and molecular phylogeny of Macaronesian island Tarphius (Coleoptera: Zopheridae): why so few species in the Azores?Publication . Amorim, Isabel R.; Emerson, Brent C.; Borges, Paulo A. V.; Wayne, Robert K.AIM: We used a phylogenetic framework to examine island colonization and predictions pertaining to differentiation within Macaronesian Tarphius (Insecta, Coleoptera, Zopheridae), and explain the paucity of endemics in the Azores compared with other Macaronesian archipelagos. Specifically, we test whether low diversity in the Azores could be due to recent colonization (phylogenetic lineage youth), cryptic speciation (distinct phylogenetic entities within species) or the young geological age of the archipelago. LOCATION: Macaronesian archipelagos (Azores, Madeira and the Canary Islands), northern Portugal and Morocco. METHODS: Phylogenetic analyses of mitochondrial and nuclear genes of Tarphius beetles of the Azores, other Macaronesian islands and neighbouring continental areas were used to investigate the origin of island biodiversity and to compare patterns of colonization and differentiation. A comparative nucleotide substitution rate test was used to select the appropriate substitution rate to infer clade divergence times. RESULTS: Madeiran and Canarian Tarphius species were found to be more closely related to each other, while Azorean taxa grouped separately. Azorean taxa showed concordance between species and phylogenetic clades, except for species that occur on multiple islands, which segregated by island of origin. Divergence time estimates revealed that Azorean Tarphius are an old group and that the most recent intra-island speciation event on Santa Maria, the oldest island, occurred between 3.7 and 6.1 Ma. MAIN CONCLUSIONS: Our phylogenetic approach provides new evidence to understand the impoverishment of Azorean endemics: (1) Tarphius have had a long evolutionary history within the Azores, which does not support the hypothesis of fewer radiation events due to recent colonization; (2) the current taxonomy of Azorean Tarphius does not reflect common ancestry and cryptic speciation is responsible for the underestimation of endemics; (3) intra-island differentiation in the Azores was found only in the oldest island, supporting the idea that young geological age of the archipelago limits the number of endemics; and (4) the lack of evidence for recent intra-island diversification in Santa Maria could also explain the paucity of Azorean endemics. Phylogenetic reconstructions of other species-rich taxa that occur on multiple Macaronesian archipelagos will reveal whether our conclusions are taxon specific, or of a more general nature.
- Aerosol optical properties at Santiago Island, Cape Verde.Publication . Cerqueira, Mário; Pio, Casimiro; Fialho, Paulo; Cardoso, João; Nunes, Teresa; Almeida, S. M.> huge amounts of mineral dust are emitted every year from the Sahara desert to the atmosphere; > optical parameters of mineral aerosols determine the direct interaction of solar and terrestrial radiation in the atmosphere through scattering and absorption; > mineral dust has a great impact on cloud formation leading to additional indirect radiation effects; > The dense haze from dust events is also known to affect visibility.
- Can islets be considered repositories of neighbouring coastal biodiversity?Publication . Moniz, Isadora; Prestes, Afonso L.; Nogueira, Eunice M.; Azevedo, José M. N.; Álvaro, Nuno V.; Neto, Ana I.
- New records of Macroalgae from Madeira Archipelago.Publication . Ferreira, Sara; Kaufmann, Manfred; Neto, Ana I.; Izaguirre, Juan P.; Wirtz, Peter; de Clerck, Olivier
- Total lipid content, fatty acid profile and nutritional value of selected macroalgae from S. Miguel Island littoral zone.Publication . Paiva, Lisete S.; Lima, Elisabete M. C.; Baptista, José A. B.; Patarra, Rita F.; Neto, Ana I.
- Isolation and screening of indigenous strains of Haematococcus pluvialis Flotow for biomass and astaxanthin productionPublication . Xavier, Emanuel D.; Azevedo, José M. N.; Teves, Luis; Mota, Gonçalo; Neto, Ana I.
- Exposure of thermoelectric power-plant workers to volatile organic compounds from fuel oil: Genotoxic and cytotoxic effects in buccal epithelial cellsPublication . Garcia, Patrícia; Linhares, Diana P.; Amaral, A. F. S.; Rodrigues, ArmindoThermoelectric power-plant workers are constantly exposed to high levels of potentially genotoxic gaseous substances, such as volatile organic compounds (VOCs) from the combustion of fuel oil or the processing of naphtha. The aim of the present study was to estimate the association between such occupational exposure and the frequency of micronucleated cells and cells with other nuclear anomalies. Buccal epithelial cells were collected from a total of 44 power-plant workers (exposed group) and 47 administrative workers (non-exposed group), and examined for the frequency of micronucleated cells (MNC) and of cells with other nuclear anomalies (ONA: pyknosis, karyolysis, and karyorrhexis) by means of the micronucleus assay. The frequencies of MNC and ONA per 1000 cells in the exposed group (1.8‰ and 82.4‰, respectively) were significantly higher than in the non-exposed group (0.2‰ and 58.3‰, respectively). The exposed group had a twelve-fold increase in risk for formation of MNC compared with non-exposed individuals (RR = 12.1; 95% CI, 5.0–29.2; P < 0.001). The confounding factors analyzed (age, smoking status, alcohol consumption, and mouthwash use) did not show any significant association with the frequency of MNC or ONA. The findings of this study show that workers from power plants exposed to VOCs have a significantly elevated risk for DNA damage. Therefore, bio-monitoring of DNA damage is recommended for this group of workers.
- Investigação-ação sobre questões curriculares: Quem define a agenda?Publication . Sousa, FranciscoEm grande parte da literatura dedicada à investigação-ação educacional assume-se o pressuposto de que a concretização desta abordagem é necessariamente liderada por "práticos", isto é, professores ou outros profissionais do ensino não superior. A participação de investigadores profissionais é, nalguns casos, explícita ou implicitamente considerada dispensável. Noutros casos, é referida como característica de projetos de investigação-ação colaborativa nos quais os referidos investigadores assumem o papel de facilitadores externos, ficando a iniciativa de conceber o projeto, a identificação do problema a investigar e a realização das principais tarefas a cargo dos "práticos". No entanto, há também relatos de projetos de investigação-ação iniciados por universitários, apesar de centrados em preocupações sentidas por profissionais do ensino não superior relativamente a problemas que surgem nas suas salas de aula. É o caso do projeto discutido nesta comunicação, que foi implementado entre 2007 e 2012 em salas de aula de seis escolas portuguesas nas quais foram assinalados determinados problemas de natureza curricular, que foram sendo enfrentados através da investigação-ação por uma equipa que incluiu professores do ensino básico e do ensino superior. Ao longo da comunicação, discutiremos uma série de questões relativas ao equilíbrio entre a agenda dos professores do ensino básico que participaram no referido projeto e a agenda dos investigadores universitários que o coordenaram. A análise da implementação do projeto evidencia alguma autonomização dos professores do ensino básico. A sua responsabilização pela identificação dos problemas a investigar e pela conceção de estratégias de abordagem aos mesmos aumentou bastante no último ano do projeto. Além de discutirmos questões relativas à legitimidade do elevado grau de envolvimento dos investigadores universitários na fase inicial do projeto, apresentaremos e comentaremos evidências do aumento do grau de participação e responsabilização dos professores do ensino básico. Concluiremos a comunicação com algumas reflexões sobre a indução externa da investigação-ação e de outras formas de investigação em determinados contextos.
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