Repositório da Universidade dos Açores
Repositório Institucional da Universidade dos Açores
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Muitas vozes, uma língua: o português com sotaques e histórias
Publication . Amaral, Diana; Coordenação e edição de Ana Teresa Alves (FCSH-UAc)
Já reparaste como a língua que falamos, o português, soa de forma diferente conforme a região do país? Um açoriano não fala como um algarvio, que não fala como um transmontano. E todos estão a falar português. As variações regionais da língua podem ocorrer em qualquer área da gramática e originam os diferentes dialetos (falares típicos de uma região). Estes são uma das provas mais fascinantes de que a língua é viva, dinâmica e está sempre a mudar.
Histological Evidence of Thyroid Disruption in Wild Mice from Conventional and Organic Farming Environments
Publication . Coelho, Nádia; Carminho, Ricardo; Garcia, Patrícia; Bernardo, Filipe; dos Santos Rodrigues, Armindo; Fortin, Claude
ABSTRACT: The main objective of this work is to assess the potential negative impact of organic farming on the thyroid gland and compare it with the negative impact of conventional farming on this organ. Previous studies have linked exposure to conventional farming with thyroid disruption; relatively less is known about effects of exposure to organic farming on the thyroid. Mus musculus were the bioindicators in this work, captured in a conventional farm (CF), an organic farm (OF), and two reference areas (RF’) without agriculture. Histomorphometric and histomorphological measurements of the thyroid were performed. Hypothyroidism signs were observed in mice exposed to either farming system, being less pronounced in organic farming-exposed mice: epithelium thickness and the epithelial cells’ area and volume were lower than in non-exposed mice [epithelium thickness (µm): 4.16 ± 0.51 (CF); 6.28 ± 0.19 (OF); 7.46 ± 0.25 (RF’)]. Histomorphologic alterations included decreased follicular sphericity, increased epithelium irregularity, increased exfoliation into the colloid, and increased inflammation of thyroid tissue. Results suggest that, while organic farming might be a better alternative to conventional farming, it is not completely free of health hazards. Exposure to an organic farming environment can cause thyroid disruption, although with less pronounced effects than conventional farming. Despite there being risks to be considered, results support the benefit of transitioning from conventional farming systems towards organic farming systems.
Why are so few island bryophytes endemic?
Publication . Mirolo, Sébastien; Ledent, Alice; González-Mancebo, Juana; Gabriel, Rosalina; Sim-Sim, Manuela; Collart, Flavien; Patiño, Jairo; Vanderpoorten, Alain
ABSTRACT: Endemism, a hallmark of island biodiversity, reaches its lowest levels among bryophytes compared with other land plants. Whether this pattern reflects low diversification rates, and why, or whether it is a result of loss of endemicity due to extinctions or subsequent continental (back-)colonization, is examined here through a review of available evidence in the Macaronesian flora. Significant genetic differentiation (GST, based on allele frequencies) was consistently found between Macaronesian and continental populations, ruling out the hypothesis that intense migrations necessarily hamper differentiation. A significant phylogeographical signal in the data (NST > GST; where NST is a GST analog incorporating phylogenetic relationships among alleles), involving higher mutation rates than dispersal rates and evidencing incipient speciation, was further found in more than 1/3 of the species investigated. The significantly higher average NST between extra-European regions and Macaronesia compared to Europe and Macaronesia suggests, however, that incipient speciation is more likely to occur between distant (Macaronesian versus extra-European) than closer (Macaronesian versus European) populations. In line with this, ancestral area estimations in Macaronesian endemic bryophyte species revealed that at least 50% of them have an extra-European origin, in contrast with the almost exclusively (>90%) European/Mediterranean origin of Macaronesian endemic spermatophytes. Allopatric speciation via long-distance dispersal and subsequent divergence of a single endemic species prevails in island bryophytes, wherein sympatric radiations virtually never occur. Such a speciation mode does not trigger high rates of endemism, in contrast to radiations in Macaronesian spermatophytes, which contribute to 56% of the total number of endemics. Several mechanisms may explain the failure of island bryophytes to diversify in situ, including the fact that oceanic islands are too small or insufficiently isolated from each other or from continents to promote sympatric speciation, the lack of key innovations, and phylogenetic niche conservatism for stable habitats not prone to trigger radiations. In comparison with spermatophytes, continental (back-)colonization further largely prevails in bryophytes and, unlike in many instances in angiosperms, is not followed by in situ speciation on the mainland. The consequent loss of the endemic status of species that did speciate on islands but subsequently enlarged their range further accounts for the low rates of endemism among island bryophyte floras and invalidates the use of endemism rates as a proxy of speciation rates in this group.
Ignorar a Estatística tem consequências: quem paga o preço?
Publication . Silva, Osvaldo; Gráfica Açoreana
Vivemos rodeados de números, mas isso não significa necessariamente que saibamos o que fazer com eles. Percentagens surgem nos noticiários como se fossem verdades absolutas, gráficos coloridos circulam nas redes sociais como provas irrefutáveis e são apresentadas com frequência previsões com uma confiança que deixam qualquer investigador, competente e honesto intelectualmente, boquiaberto e a corar de espanto perante as barbaridades que são relatadas como verdades inquestionáveis. Paradoxalmente, nunca tivemos tantos dados e nunca foi tão evidente a fragilidade da nossa literacia estatística coletiva. […]. Investir na formação em literacia estatística - desde o ensino básico até ao ensino superior e à educação ao longo da vida - é investir numa sociedade mais preparada para enfrentar riscos, tomar decisões informadas e construir futuros coletivos mais seguros e equitativos. Num tempo em que os dados moldam políticas e escolhas, compreender Estatística é, cada vez mais, compreender o mundo. Num mundo marcado por desafios globais e incerteza crescente, a capacidade de usar dados de forma crítica e responsável é uma condição essencial para a sustentabilidade, a justiça social e o bem comum. Reflita sobre isto: o momento de agir é agora, e depende apenas de si.
The proper middle class: assessing the importance of subordinate species on plant community assembly and functional diversity
Publication . Ulrich, Werner; Matthews, Thomas; Biurrun, Idoia; Aleksanyan, Alla; Borovyk, Dariia; Burrascano, Sabina; Campos, Juan Antonio; Chusova, Olha; Czarniecka-Wiera, Marta; Czortek, Patryk; Dembicz, Iwona; Essl, Franz; Janišová, Monika; Labadessa, Rocco; Napoleone, Francesca; Pielech, Remigiusz; Vynokurov, Denys; Puchałka, Radosław; Peres-Neto, Pedro
ABSTRACT: The local species abundance distribution (SAD) and the associated distributions of species functional traits (TADs) both result from the process of plant community assembly. Community assembly has been extensively studied for dominant and rare plants, while subordinates, the species of intermediate abundance in a community, have received less research attention although this group is comparatively species rich and important for community functioning. Here, we study the functional role of subordinate species (those covering the intermediate 50% of abundance ranks) using a large data set of Palearctic dry and semi-dry grassland plant communities and data on specific leaf area, seed mass and plant height. Our findings indicate that species rank orders of SADs and TADs tend to be negatively correlated, causing the TAD to have higher evenness than the associated SAD. Subordinate species represented on average less than 15% of total plant abundance and trait space. Functional diversity of subordinates was lower than expected by a null model that assumed an equiprobable random distribution of trait values among plant species. Climate seasonality and elevation appeared to be the most important drivers of subordinate abundance and functional diversity. We conclude that subordinates differ from dominants in trait composition, leading to their partial functional independence from dominants.