Browsing by Issue Date, starting with "2011"
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- In memory of Richard Honrath. Pico Mountain, Why should we continuum?Publication . Fialho, Paulo
- Aspects of reproduction in pink dentex Dentex gibbosus (Rafinesque, 1810) from the Archipelago of Madeira in the northeast AtlanticPublication . Alves, Adriana; Faria, Graça; Reis, Rui; Pinto, Ana R.; Vieira, SandraThis work describes and identifies the macroscopic, and corresponding microscopic, changes of gonads through the annual reproductive cycle of pink dentex, Dentex gibbosus, from the Madeira Archipelago. This new contribution focused on validating a macroscopic maturity scale for this species using a histological technique. A total of 906 individuals were collected from waters around the Madeira Archipelago between September 1997 and December 2008. A six-stage maturity scale based on macroscopic characteristics was used to classify the gonads. The overall ratio of males to females was 1:1.12. The annual gonad development, together with the analysis of monthly indices (gonadosomatic and hepatoso-matic) and complementary histological observations allowed us to conclude that spawning takes place during the summer months, with a peak in May-June.
- Vegetative propagation of the endangered Azorean tree, Picconia azoricaPublication . Martins, José; Moreira, Orlando; Silva, Luís; Moura, MónicaPicconia azorica (Tutin) Knobl. (Oleaceae), commonly named “pau-branco”, is an endangered tree endemic to the Azores. Vegetative propagation may be important for the preservation of this species, particularly in depauperate populations, with low seed set. The objective of this study was to evaluate effective techniques for the vegetative propagation of P. azorica by rooting of stem cuttings or by air layering. Rooting substrate, IBA concentration, and the portion of the area of the terminal leaf pair kept on stem cuttings, when tested in early spring (semi-hardwood cuttings) and autumn (hardwood cuttings) failed to produce any rooted cuttings. In contrast, air layering performed in the autumn on lateral branches of adult trees was successful. After 12 months, air layers treated with 5000 ppm of IBA in talc achieved 65% rooting, while those treated with 2500 ppm IBA or without growth regulator only attained 41 and 28% rooting, respectively. Our study indicates that P. azorica is relatively easy to propagate by air layering. This method could be used to restore natural populations of P. azorica when seeds are not available or plant competition impairs natural regeneration.
- Segregating characters used within Amphiroa (Corallinales, Rhodophyta) and taxonomic reevaluation of the genus in the AzoresPublication . Rosas-Alquicira, Edgar; Riosmena-Rodriguez, Rafael; Neto, Ana I.A compilation of the published morphological and anatomical characters used in species diagnosis within the genus Amphiroa (Corallinales, Rhodophyta) was made and their expression was evaluated in 142 specimens collected in the Azores. An evaluation of the genus diversity in this archipelago was undertaken. Morphological and anatomical features here selected as diagnostic characters of Amphiroa in the Azorean plants include shape of the thallus, branching origin, morphology of the apical intergenicula in transverse section, number of cell tiers per mature geniculum and pattern of long vs. short intergenicular tiers of cells. The occurrence of Amphiroa beauvoisii and Amphiroa cryptarthrodia was confirmed in the Azores. The form cyathifera of the species Amphiroa fragilissima is newly reported for the Archipelago. Amphiroa exilis and Amphiroa rigida, the other species recorded in the area, were not observed. A morphological and anatomical account is provided for the studied species and comparisons made with both type material and material from the same species from other regions.
- (Des)Encontros Artísticos: O Olhar Crítico de Mark Twain Sobre os Mestres EuropeusPublication . Silva, Leonor Sampaio daA viagem de Mark Twain pela Europa, iniciada a 8 de junho de 1867, é o ponto de partida para um estudo que analisa as leituras que o americano faz dos grandes mestres europeus no livro resultante das suas impressões de viagem, "The Innocents Abroad". A crítica aos modelos europeus acompanha a reflexão sobre a identidade americana em contraste com a europeia e prefigura a importância de questões centrais no âmbito dos Estudos Visuais, como a relação entre pintura e literatura, ou imagem e palavra.
- Será o óptimo inimigo do bom?Publication . Mendes, Armando B."[…]. O processo de optimização passa por uma simplificação da realidade, resultando num modelo do sistema com um conjunto reduzido de alternativas de decisão ou de objectivos e restrições. Assim, por razões mais ou menos inesperadas ou não incluídas na análise, a solução identificada como óptima, pode na verdade não ser adequada ou ter impactos negativos tão elevados que não compensa a pequena melhoria entre a solução boa e a óptima. No entanto, tal só pode resultar de uma análise do problema inicial incompleta ou da aplicação de uma metodologia desadequada. […]."
- A re-evaluation of Scinaia (Nemaliales, Rhodophyta) in the Azores.Publication . Léon-Cisneros, Karla; Riosmena-Rodriguez, Rafael; Neto, Ana I.The genus Scinaia in the Azores is re-evaluated based on historical and recent collections. A combination of morphological and anatomical diagnostic characters was used for species segregation, and a key for Azorean species determination is presented. Anatomical information associated to the hair development is described for the first time for the genus. The occurrence of S. furcellata and S. interrupta is confirmed for the archipelago. The presence of S. acuta is reported for the first time in the Azores, representing a spread from Australia to the N-Atlantic and specifically into the Macaronesian region. Its occurrence in the archipelago and the Canaries is discussed as a possible introduction.
- As Saudades do Céu do Doutor Gaspar FrutuosoPublication . Luz, José Luís Brandão daA apresentação das Saudades do Céu do Doutor Gaspar Frutuoso (1522-1591), por ocasião da sua edição pelo Instituto Cultural de Ponta Delgada, permitiu evocar alguns dados biográficos do mais antigo cronista dos Açores e, simultaneamente, colocar em destaque o carácter alegórico desta sua obra, que os autores, em geral, consideram ter ficado incompleta.
- Modelling the distribution of cetaceans using opportunistic presence-only data in S. Miguel Island (Azores)Publication . Fernandez, Marc; Azevedo, José M. N.The distribution of cetaceans has always been a difficult and polemic issue, and more so in open waters and pelagic habitats. Due to the high economic cost of surveying and the low detectability of certain cetacean species, the distribution of many cetacean species remains poorly known in many areas. In this work we explore the potential of Spatial Distribution Modelling using presence-only models to obtain a potential distribution map of cetacean populations from opportunistic data. We used opportunistic data from the MONICET database, provided by commercial whale-watching operations in the Azores using a standard, validated, methodology. Two different presence-only models were applied, the Genetic Algorithm for Rule-Set Production (GARP) and the Maximum Entropy Modelling (MaxEnt). Using different GIS programs we prepared a set of different bathimetric derived ecogeographical variables: Depth, Slope, Rugosity and Bathimetric Position Index, using the Bathimetric Terrain Modeller Extension for ArcGIS to calculate the last two. A comparison of the performance of the two different models was carried out, using the Area Under the Curve (AUC) of the Receiver Operator Curve (ROC) and expert knowledge as key factors to see which one of the models produce more realistic results. The relevance of each variable in the models was evaluated using a Jacknife test. The results of this study could be used in a future for a conservation and management purposes in the Azorean waters.
- Notas Para a Elucidação do Conceito de "Ciência"Publication . Silva, EduardoO presente escrito ("Notas para a Elucidação do Conceito de 'Ciência'") visa, como o seu próprio título indica, definir e elucidar o conceito de 'Ciência', bem como pôr em evidência quais são as relações conceptuais que subsistem entre a ciência e a filosofia e a própria ciência e a cultura (entendida esta sobretudo no sentido de 'mundividência').