129 research outputs found

    Promoting a spatial perspective on primary students through geotechnologies

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    Limitações na avaliação de perturbação de personalidade: Aspectos conceptuais e metodológicos

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    Nas últimas décadas, tem havido um aumento acentuado na produção de instrumentos destinados a avaliar perturbação de personalidade. Muitos desses instrumentos baseiam-se na taxonomia expressa no Eixo II do DSM apesar de vários autores terem chamado a atenção para diversos problemas conceptuais e metodológicos deste sistema de classificação. O objectivo do presente artigo é pois descrever e caracterizar os principais problemas psicométricos inerentes aos instrumentos de avaliação baseados no DSM tais como a existência de elevadas taxas de co-morbilidade entre as diversas perturbações de personalidade, ausência de concordância entre instrumentos, foco exclusivo nos sintomas, falta de ênfase desenvolvimental e divergência em relação à prática clínica. Parece pois necessário conduzir estudos sobre a validade dos construtos associados à noção actual de perturbação de personalidade e desenvolver instrumentos alternativos que possam obter uma aceitação mais generalizada. Deste modo, o artigo termina com uma breve exposição de algumas das contribuições oferecidas até ao momento, nomeadamente pelas teorias psicanalíticas, no sentido de tentar colmatar algumas das falhas apontadas na avaliação deste tipo de patologia

    Zircon dating and inheritance of a pre-Variscan granite, SW Iberia

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    The Portalegre pluton is an aligned series of Pre-Variscan granitoids located along the boundary of the Central Iberian/ Ossa Morena Zones (SW Iberian Massif, Portugal). Singlezircon geochronology (U-Pb SHRIMP and Pb/Pb stepwise evaporation) yield an Upper Cambrian/Lower Ordovician age (492.7 ± 3.5 Ma) interpreted as the magmatic crystallization age. The inherited zircon cores indicate the involvement of sources with a wide range age-components: an important Late Neoproterozoic (548 ± 7 Ma and c. 611-681 Ma) population and a Mesoproterozoic (c. 0.95-1.1 Ga) and older (c. 2.6 Ga) components. Younger zircon ages of 358 ± 36 and 387 ± 7 Ma were also found and interpreted as the record of a Variscan metamorphic event. The presence of Grenvillian zirconforming events in the protholiths of Portalegre granites is significant in the regional geodynamic context of the Iberian Massif (Central Iberian affinity?). At present, the Grenvillian ages are not noticeable in the Late Neoproterozoic/Early Cambrian record of the Ossa-Morena Zone, that has been correlated with West African Craton [1]. These data suggests that the Central Iberian Zone and Ossa-Morena Zone were independent peri-gondwana terrains with diferent paleogeographic affinities before the Ordovician times. The overall chemistry for the Portalegre granites shows they are very differentiated (SiO2=74-76 wt %), peraluminous (A/CNK=1.1–1.4); have low Zr=36-125ppm, Th/Ta=2-10, ΣREE= 22-134 and 1000Ga/Al >3. Their isotopic signatures (87Sr/86Sr)493=0.7050-0.7065, εNd493(-2.88 to -0.85) and δ18O=10.5-10.8‰, are compatible with partial melting of relatively young recycled metaigneous ± enriched mantle sources. The age pattern from the inherited zircon cores in the Portalegre granites shows that the late Neoproterozoic age (Cadomian) basement was actively involved in their magma generation. The Grenvillian and Archaean zircons can be accounted for by that source component but they do not imply the presence of an older pre-Neoproterozoic basement rocks beneath SW Iberia

    Le magmatisme terminal de la chaîne hercynienne : signification géodynamique d'une association magmatique identifiée dans le Carbonifère terminal du Massif Hercynien Central Marocain

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    Na parte oriental do Maciço Hercínico Central de Marrocos afloram alguns filões intercalados em formações do Carbónico superior do Sudeste da bacia de Azrou-Kénifra. Estes filões instalaram-se paralelamente à estratificação e foram deformados por dobramentos associados aos cavalgamentos que controlaram a sedimentação, o que demonstra o seu carácter sintectónico. A sua composição química permitiu distinguir dois tipos de sequências magmáticas sobrepostas nas séries de Tariwalt e Talgarat, respectivamente de idades V3b e Namuriano-V3c, provável. A primeira inclui rochas básicas de carácter transicional e afinidade alcalina, enquanto a segunda possui uma assinatura calco-alcalina. Estas sequências magmáticas apresentam estreitas semelhanças petrográficas e geoquímicas com as que ocorrem em ambientes de margem activa. As assinaturas geoquímicas e a evolução magmática destas rochas são compatíveis com os dados tectono-sedimentares que caracterizam a bacia de Azrou-Kénifra como uma bacia desenvolvida em regime compressivo, integrada num sistema de "avant pays" determinado por sequências de cavalgamentos propagando-se para NW

    Syn-rift unconformities punctuating the lower-middle Cambrian transition in the Atlas Rift, Morocco

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    The Cambrian Tamdroust and Bab n’Ali Volcanic Complexes represent two magmatic episodes developed in the latest Ediacaran–Cambrian Atlas Rift of Morocco. Their rifting pulses were accompanied by accumulation of volcanosedimentary edifices (dominated by effusive lava flows in the former and explosive acidic aprons in the latter) associated with active tilting and uplift. Sealing of their peneplaned horst-and-graben palaeotopographies led to the onset of distinct onlapping geometries and angular discordances capping eroded basements ranging from the Ediacaran Ouarzazate Supergroup to the Cambrian Asrir Formation. Previous interpretations of these discordances as pull-apart or compressive events are revised here and reinterpreted in an extensional (rifting) context associated with active volcanism. The record of erosive unconformities, stratigraphic gaps, condensed beds and onlapping patterns across the traditional “lower–middle Cambrian” (or Cambrian Series 2–3) transition of the Atlas Rift must be taken into consideration for global chronostratigraphic correlation based on their trilobite content

    Socioeconomic disparities in early language development in two Norwegian samples

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    Socioeconomic disparities in early language are widespread and have long-lasting effects. The aim of this study is to investigate when social gaps in language problems arise and how they change across the first years of schooling. We address this question in two large longitudinal Norwegian datasets: the Behavior Outlook Norwegian Developmental Study (BONDS) and the Norwegian Mother, Father and Child Cohort Study (MoBa). Despite some slight differences across the two samples, we found that children from higher social backgrounds are less likely to have language difficulties starting from age 18 months and up to age 8 (grade 2). Moreover, while early language problems are strongly predictive of later language, maternal education makes an additional contribution to explaining language difficulties at the beginning of school life. Social inequality in language development arises early, even in a country like Norway, with low unemployment and one of the most egalitarian societies in Europe.info:eu-repo/semantics/acceptedVersio

    Commercial Gold Complexes Supported on Functionalised Carbon Materials as Efficient Catalysts for the Direct Oxidation of Ethane to Acetic Acid

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    UIDB/00100/2020 UIDP/00100/2020 LA/P/0056/2020 IST-ID/119/2018 SFRH/BD/146426/2019 CEEC-INST/00102/2018 UIDB/50006/2020 UIDP/50006/2020 Base-UIDB/50020/2020 Programmatic-UIDP/50020/2020The single-pot efficient oxidation of ethane to acetic acid catalysed by Au(I) or Au(III) compounds, chlorotriphenylphosphinegold(I) (1), chlorotrimethylphosphinegold(I) (2), 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidenegold(I) chloride (3), dichloro(2-pyridinecarboxylato)gold(III) (4), homogenous and supported on different carbon materials: activated carbon (AC), multi-walled carbon nanotubes (CNT) and carbon xerogel (CX), oxidised with nitric acid followed by treatment with NaOH (-ox-Na), is reported. The reactions were performed in water/acetonitrile. The materials were selective for the production of acetic acid, with no trace of by-products being detected. The best homogenous catalysts were complexes 2 and 3 which showed the highest ethane conversion and an acetic acid yield of ca. 21%, followed by 4 and 1. The heterogenised materials showed much better activity than the homogenous counterparts, with acetic acid yields up to 41.4% for 4@CNT-ox-Na, and remarkable selectivity (with acetic acid being the only product detected). The heterogenised catalysts with the best results were reused up to five cycles, with no significant loss of activity, and maintaining high selectivity for acetic acid. 4@CNT-ox-Na showed not only the best catalytic activity but also the best stability during the recycling runs.publishersversionpublishe
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