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- Can we predict personality in fish? searching for consistency over time and across contextsPublication . Castanheira, Maria Filipa; Herrera, Marcelino; Costas, Benjamin; Conceicao, Luis E. C.; Martins, Catarina I. M.The interest in animal personality, broadly defined as consistency of individual behavioural traits over time and across contexts, has increased dramatically over the last years. Individual differences in behaviour are no longer recognised as noise around a mean but rather as adaptive variation and thus, essentially, raw material for evolution. Animal personality has been considered evolutionary conserved and has been shown to be present in all vertebrates including fish. Despite the importance of evolutionary and comparative aspects in this field, few studies have actually documented consistency across situations in fish. In addition, most studies are done with individually housed fish which may pose additional challenges when interpreting data from social species. Here, we investigate, for the first time in fish, whether individual differences in behavioural responses to a variety of challenges are consistent over time and across contexts using both individual and grouped-based tests. Twenty-four juveniles of Gilthead seabream Sparus aurata were subjected to three individual-based tests: feed intake recovery in a novel environment, novel object and restraining and to two group-based tests: risk-taking and hypoxia. Each test was repeated twice to assess consistency of behavioural responses over time. Risk taking and escape behaviours during restraining were shown to be significantly consistent over time. In addition, consistency across contexts was also observed: individuals that took longer to recover feed intake after transfer into a novel environment exhibited higher escape attempts during a restraining test and escaped faster from hypoxia conditions. These results highlight the possibility to predict behaviour in groups from individual personality traits.
- O problema de Monty Hall e as probabilidades condicionadasPublication . Fernandes, Susana; Pinto, Mónica MartinsO problema de Monty Hall, também conhecido como o problema das 3 portas, surgiu a partir de um concurso televisivo dos Estados Unidos apresentado por Monty Hall na década de 1970. O concurso chamava-se “Let’s Make a Deal” e incluía o seguinte jogo: São apresentadas ao concorrente três portas fechadas e este é informado que atrás de uma das portas existe um bom prémio (automóvel) e atrás das outras duas estão prémios sem valor. Numa primeira etapa o concorrente deverá escolher uma das portas para ficar com o prémio que esta oculta. Na segunda etapa, após a escolha do concorrente, o apresentador, que sabe onde está o bom prémio, abre uma das portas não escolhidas, que não esconda o automóvel. Na terceira etapa do jogo o concorrente pode optar por manter a porta que escolheu no início ou trocar a sua escolha para a outra porta não aberta. Coloca-se a questão: O que será mais vantajoso para o concorrente, manter a escolha que fez na primeira etapa ou trocar a porta escolhida para abrir? Intuitivamente somos levados a pensar que, em termos probabilísticos, será indiferente trocar ou não a porta escolhida, mas na verdade o concorrente tem mais hipóteses de ganhar se decidir trocar a sua escolha inicial.
- Long-term panmixia in a cosmopolitan Indo-Pacific coral reef fish and a nebulous genetic boundary with its broadly sympatric sister speciesPublication . Horne, John B.; van Herwerden, L.Phylogeographical studies have shown that some shallow-water marine organisms, such as certain coral reef fishes, lack spatial population structure at oceanic scales, despite vast distances of pelagic habitat between reefs and other dispersal barriers. However, whether these dispersive widespread taxa constitute long-term panmictic populations across their species ranges remains unknown. Conventional phylogeographical inferences frequently fail to distinguish between long-term panmixia and metapopulations connected by gene flow. Moreover, marine organisms have notoriously large effective population sizes that confound population structure detection. Therefore, at what spatial scale marine populations experience independent evolutionary trajectories and ultimately species divergence is still unclear. Here, we present a phylogeographical study of a cosmopolitan Indo-Pacific coral reef fish Naso hexacanthus and its sister species Naso caesius, using two mtDNA and two nDNA markers. The purpose of this study was two-fold: first, to test for broad-scale panmixia in N.hexacanthus by fitting the data to various phylogeographical models within a Bayesian statistical framework, and second, to explore patterns of genetic divergence between the two broadly sympatric species. We report that N.hexacanthus shows little population structure across the Indo-Pacific and a range-wide, long-term panmictic population model best fit the data. Hence, this species presently comprises a single evolutionary unit across much of the tropical Indian and Pacific Oceans. Naso hexacanthus and N.caesius were not reciprocally monophyletic in the mtDNA markers but showed varying degrees of population level divergence in the two nuclear introns. Overall, patterns are consistent with secondary introgression following a period of isolation, which may be attributed to oceanographic conditions of the mid to late Pleistocene, when these two species appear to have diverged.
- The morphology, behaviour and molecular phylogeny of Phytophthora taxon Salixsoil and its redesignation as Phytophthora lacustris sp nov.Publication . Nechwatal, J.; Bakonyi, J.; Cacciola, S. O.; Cooke, D. E. L.; Jung, Thomas; Nagy, Z. A.; Vannini, A.; Vettraino, A. M.; Brasier, C. M.Since its first isolation from Salix roots in 1972, isolates of a sexually sterile Phytophthora species have been obtained frequently from wet or riparian habitats worldwide and have also been isolated from roots of Alnus and Prunus spp. Although originally assigned to Phytophthora gonapodyides on morphological grounds, it was recognized that these isolates, informally named P.taxon Salixsoil, might represent a separate lineage within ITS Clade 6. Based on phylogenetic analyses and comparisons of morphology, growth-temperature relationships and pathogenicity, this taxon is formally described here as Phytophthora lacustris sp. nov. Isolates of P.lacustris form a clearly resolved cluster in both ITS and mitochondrial cox1 phylogenies, basal to most other Clade 6 taxa. Phytophthora lacustris shares several unusual behavioural properties with other aquatic Clade 6 species, such as sexual sterility and tolerance of high temperatures, that have been suggested as adaptations to riparian conditions. It appears to be widespread in Europe and has also been detected in Australia, New Zealand and the USA. It was shown to be weakly or moderately aggressive on inoculation to Alnus, Prunus and Salix. The extent of P.lacustris' activity as a saprotroph in plant debris in water and as an opportunistic pathogen in riparian habitats needs further investigation. Its pathogenic potential to cultivated fruit trees also deserves attention because P.lacustris has apparently been introduced into the nursery trade.
- An overview of the submerged sea caves of Sagres (South of Portugal-Algarve)Publication . Monteiro, PedroThe submerged sea caves of Sagres are located within the “Parque Natural do Sudoeste Alentejano e Costa Vicentina (PNSACV)” Marine Protected Area (MPA). This MPA integrates the national network of protected areas, addressed by the National Institute for Nature Conservation and Forest (ICNF) and was declared Site of Community Importance (SCI) under the Habitats Directive. Under the Annex I from the Habitat Directive these habitat caves are included in “8330 Submerged or partially submerged sea caves”. This conservation status should provide sufficient concern to have detailed information on biodiversity. However, among marine researcher, little is still known about these submerged sea caves and tunnels habitats. The only well-known study dealing with the Sagres sea caves was conducted in the late 80s and was only published in 2001. For effective management of such specific habitats a clear understanding of their localization and extension, the assessment of the biological communities, its conservation importance, its monitoring options and their sensitivity to natural change and human disturbance need to be a relatively clear. This report, produced under the MeshAtlantic Project, provides an overview of the available published and unpublished information relevant for the conservation management of the subtidal caves of Sagres. It mainly aims to be a base contribution for future studies.
- Tris(pyrazolyl)methane molybdenum tricarbonyl complexes as catalyst precursors for olefin epoxidationPublication . Gomes, Ana C.; Neves, Patrícia; Figueiredo, Sónia; Fernandes, José A.; Valente, Anabela A.; Almeida Paz, Filipe A.; Pillinger, Martyn; Lopes, Andre D.; Gonçalves, Isabel S.The molybdenum tricarbonyl complexes [Mo(CO)3(HC(3,5-Me2pz)3)] (1) and [Mo(CO)3(HC(pz)3)] (2)(HC(3,5-Me2pz)3 = tris(3,5-dimethyl-1-pyrazolyl)methane, HC(pz)3 = tris(1-pyrazolyl)methane) were obtained in good yields by the microwave-assisted reaction of Mo(CO)6 with the respective organic ligand. Complete oxidative decarbonylation of 1 and 2 was achieved by reaction with excess tert-butylhydroperoxide (TBHP) in 1,2-dichloroethane at 55 ◦C. For complex 1, the (2-oxo)bis[dioxomolybdenum(VI)] hexamolybdate of composition [{MoO2(HC(3,5-Me2pz)3)}2(2- O)][Mo6O19] (3) was obtained in good yield, and its structure was determined by single crystal X-ray diffraction. The compound (4) obtained by oxidative decarbonylation of 2 was not unambiguously identified, but may be chemically analogous to 3. Compounds 1–4 were examined for the first time as homogeneous (pre)catalysts for the epoxidation of olefins with TBHP, using different types of cosolvents at 55 ◦C. During the catalytic reactions 1 and 2 transform in situ into 3 and 4, respectively, and the latter two are fairly stable catalysts. Catalytic tests and characterization studies of the recovered catalysts were carried out in an attempt to understand the kinetic differences observed between the compounds prepared in situ during the catalytic reaction and those prepared prior to the catalytic reaction, from the same precursor complex.
- Protein utilisation and intermediary metabolism of Senegalese sole (Solea senegalensis) as a function of protein:lipid ratioPublication . Borges, Pedro; Medale, Francoise; Dias, Jorge; Valente, Luisa M. P.Previous experiments with Senegalese sole (Solea senegalensis) have demonstrated that dietary lipid levels above 8% impaired growth and did not promote protein retention. We hypothesised that this low ability to use high-lipid diets may depend on the dietary protein level. In the present study, a 2 x 2 factorial design was applied where two dietary lipid (4-17% DM) and two dietary protein (below and above the requirement levels, 48 and 54% DM) levels were tested in juveniles for 114 d. Growth performance was not improved by the increase in dietary fat, irrespectively of the dietary protein levels. Protein retention was similar among the diets, although fish fed the diets with high lipid content resulted in significantly lower protein gain. Among the enzymes involved in amino acid catabolism, only aspartate aminotransferase activity in the liver was affected by the dietary lipid levels, being stimulated in fish fed high-lipid diets. Moreover, phosphofructokinase 1 activity was significantly elevated in the muscle of Senegalese sole fed 4% lipid diets, suggesting enhanced glycolysis in the muscle when the dietary lipid supply was limited and dietary starch increased. The results confirmed that high-lipid diets do not enhance growth, and data from the selected enzymes support the assumption that lipids are not efficiently used for energy production and protein sparing, even when dietary protein is below the protein requirement of the species. Furthermore, data suggest a significant role of glucose as the energy source in Senegalese sole.
- Drag produced by trapped lee waves and propagating mountain waves in a two-layer atmospherePublication . Teixeira, M. A. C.; Argaín, José Luís Almaguer; Miranda, P. M. A.The surface drag force produced by trapped lee waves and upward propagating waves in non-hydrostatic stratified flow over a mountain ridge is explicitly calculated using linear theory for a two-layer atmosphere with piecewise-constant static stability and wind speed profiles. The behaviour of the drag normalized by its hydrostatic single-layer reference value is investigated as a function of the ratio of the Scorer parameters in the two layers l2/l1 and of the corresponding dimensionless interface height l1H, for selected values of the dimensionless ridge width l1a and ratio of wind speeds in the two layers. When l2/l1 1, the propagating wave drag approaches 1 in approximately hydrostatic conditions, and the trapped lee wave drag vanishes. As l2/l1 decreases, the propagating wave drag progressively displays an oscillatory behaviour with l1H, with maxima of increasing magnitude due to constructive interference of reflected waves in the lower layer. The trapped lee wave drag shows localized maxima associated with each resonant trapped lee wave mode, occurring for small l2/l1 and slightly higher values of l1H than the propagating wave drag maxima. As l1a decreases, i.e. the flow becomes more non-hydrostatic, the propagating wave drag decreases and the regions of non-zero trapped lee wave drag extend to higher l2/l1. These results are confirmed by numerical simulations for l2/l1 = 0.2. In parameter ranges of meteorological relevance, the trapped lee wave drag may have a magnitude comparable to that of propagating wave drag, and be larger than the reference single-layer drag. This may have implications for drag parametrization in global climate and weather-prediction models. Copyright (c) 2012 Royal Meteorological Society
- Aspetos metodológicos do inquérito por entrevistaPublication . Valadas, Sandra T.; Ribeiro Gonçalves, FernandoTendo com pano de fundo as perspetivas dos atores mais diretamente envolvidos no processo de avaliação externa de escolas do ensino não superior, iremos centrar-nos, fundamentalmente, na recolha de opiniões junto dos diretores de escolas relativamente ao impacto e efeitos da avaliação externa. A comunicação centrar-se-á nos diferentes tipos de entrevista (diretiva, semi diretiva e não diretiva) e procedimentos (construção, validação e aplicação). A utilização das entrevistas enquanto estratégia metodológica será devidamente contextualizada e apresentadas as vantagens da sua aplicação ao público em causa. Serão também referidas as dimensões em análise, reportadas ao projeto, e que remetem para o impacto e efeitos na escola (organizacionais, pedagógicos e curriculares) e na comunidade. Por fim, serão referidos alguns procedimentos de análise de dados utilizados no quadro de softwares específicos (N-vivo) e outros procedimentos de análise de conteúdo (categorização emergente e pré-determinada).
- A liderança escolar numa escola privada: um estudo de caso na região do AlgarvePublication . Galego, Cláudio; Valadas, Sandra T.A liderança escolar tem vindo a ser objeto de diversos estudos ao longo dos anos tendo assistido, em termos de perspetivas e modelos que suportam o conceito, a uma evolução a par das teorias de gestão e administração de empresas. Na verdade, as primeiras perspetivas sobre a liderança e gestão escolar tiveram na base trabalhos na área da gestão e administração, facto a que não são alheias as crescentes pressões para a promoção do aumento da qualidade do serviço educativo, o aumento de competitividade entre instituições de ensino ou mesmo a procura da autonomia por parte dos estabelecimentos de ensino públicos.