Repositório RCAAP

No summary/description provided

No summary/description provided

This paper presents the results of a study about the views and attitudes of students of a low achieving 11th grade class who were involved in an innovative experience with graphic calculators for all academic year. Contrasting the results obtained from a questionnaire and from interviews, it concludes that students tended to point some improvements in the mathematics class, but attributed their origin more to their teacher’ style and personality than to the use of this technology.

No summary/description provided

In this dissertation, microcantilevers are designed and fabricated. The cantilevers were dimensioned to be used in Atomic Force Microscopy in static and dynamic mode. Structures with different geometries were analysed, namely rectangular cantilevers, arrow-ended cantilevers, cantilevers with a hollow section and with different tips at the end. This work aims to obtain a cantilever with both a hollow section and a tip allowing it to be used in AFM and as a nanoparticle dispenser. Various approaches and materials were tested during the fabrication to obtain the desired features. The tips were successfully fabricated and characterized independently of the cantilever. The hollow section was not fully characterised, but it was possible to observe that the channel was closed. Silicon nitride cantilevers were successfully fabricated, however, due to the anomalous chip format, these could not be tested in a sample.

Há cerca de meio século que as preocupações com o estado do meio ambiente têm vindo a acentuar-se, sendo cada vez maiores os esforços para restabelecer um equilíbrio que o ser humano terá perturbado. No entanto, as preocupações com os ecossistemas marinhos e costeiros foram, infelizmente, negligenciadas durante as primeiras décadas em que estas questões passaram a fazer parte das agendas políticas mundiais, regionais e nacionais. A aparência quase infinita dos oceanos ajudou a criar a ilusão de que seriam capazes de absorver todos e quaisquer impactos humanos, e o facto de ser ainda um meio muito pouco explorado, terá potenciado também a tardia perceção dos verdadeiros impactos criados. Apesar disso, nas últimas décadas têm vindo a ser aplicados esforços para reverter os danos criados neste meio e, sobretudo, para encontrar um equilíbrio que permita o seu uso de forma sustentável, procurando permitir o desenvolvimento humano em consonância com a conservação da natureza. O principal objetivo deste trabalho é contribuir para a avaliação a evolução da sustentabilidade ambiental em meio marinho em Portugal, no período entre 1995 e 2018. Para tal identificaram-se um conjunto de indicadores do Sistema de Indicadores de Desenvolvimento Sustentável nacional (SIDS Portugal) passíveis de avaliar o desempenho nacional em matéria de desenvolvimento sustentável em meio marinho, procedendo em seguida à sua avaliação quantitativa e qualitativa. Para a avaliação qualitativa dos indicadores selecionados, foi considerado o desempenho de cada indicador tendo em conta a sua distância relativamente às metas estabelecidas pela Estratégia Nacional de Desenvolvimento Sustentável (ENDS 2015). Para tal foi utilizado um método equivalente a um semáforo (“Traffic Light System”), atribuindo a cada indicador uma cor consoante o seu distanciamento à meta definida. Foi ainda estabelecida uma relação entre os indicadores do SIDS Portugal avaliados com as metas do Objetivo de Desenvolvimento Sustentável 14 (ODS 14) - “Proteger a Vida Marinha” - da Agenda 2030, por forma a perceber quais destes indicadores poderão vir a ser utilizados para avaliar o desempenho nacional face os desafios deste ODS. Por fim, verificou-se a relação causa-efeito entre a evolução de Portugal em matéria de sustentabilidade no meio marinho e as suas políticas públicas de ambiente. Concluiu-se que a evolução do desenvolvimento sustentável em meio marinho em Portugal, apesar de apresentar melhorias muito significativas em alguns domínios cruciais – tais como os sistemas de drenagem e tratamento das águas residuais, a qualidade das águas balneares e as emissões de acidificantes e eutrofizantes –, existem ainda muitos aspetos a melhorar. Entre estes enumeram-se o estado das águas de superfície, a produção e gestão de resíduos, a criação de Planos de Ordenamento e Gestão para todas as áreas marinhas protegidas e o estado dos stocks pesqueiros, bem como estado de conservação das espécies marinhas em geral. Relativamente à definição de indicadores para o ODS 14 da Agenda 2030, foi possível relacionar a maioria dos indicadores às metas da Agenda, ainda que muitos possam fazer parte de uma esfera de avaliação indireta. Desde estudo, resulta a possibilidade de avaliar a evolução de cinco metas do ODS 14 desde 1995, utilizando sete indicadores SIDS Portugal.

Multimetric indices are considered a low-cost and rapid means of assessing ecological integrity in streams. This study aimed to develop a fish-based Index of Biotic Integrity (N3S-IBI) in an agricultural region within the domains of the Atlantic rainforest in Brazil. We sampled 23 first-order streams and used large-scale land use and a local physical condition index to choose reference sites and to classify sites according to the disturbance level. N3S-IBI resulted in six metrics (Simpson’s dominance; the numbers of Characiformes and non-native individuals (Poecilia reticulata); and the percentages of Characidae species, intolerant insectivorous individuals, and tolerant species), contemplating tolerance, composition, abundance, richness, trophic habits, and origin. The low number of metrics contributes to a quick and easy biomonitoring process. N3S-IBI showed an excellent performance to separate least and most disturbed sites in our study area and can provide additional knowledge about anthropogenic e ects within this impacted region. In fact, this tool could be utilized by managers to direct restoration actions for the most disturbed sites and to strengthen the preservation of the least disturbed sites.

No summary/description provided

No summary/description provided

No summary/description provided

No summary/description provided

Moringa oleifera is an edible medicinal plant used to fight malnutrition in Africa. In this study, M. oleifera flowers, fruits and seeds from Guinea-Bissau were characterized for their nutritional composition and hydroethanolic and aqueous extracts were prepared to investigate the phenolic profiles and bioactivities. Seeds presented higher levels of proteins (~31 g/100 g dw), fat (~26 g/100 g dw) and flavan-3-ol derivatives, while carbohydrates, proteins, citric acid, and glycosylated flavonoids were abundant in fruits and flowers, these last samples also being rich in α-tocopherol (~18 mg/100 g dw). Some of the identified polyphenols had never been described in M. oleifera. In general, hydroethanolic extracts contained more polyphenols and were more active against lipid peroxidation, NO production, and tumour cells growth. Significant antimicrobial effects against the tested bacteria and fungi strains were displayed by both hydroethanolic and aqueous extracts. The M. oleifera potential to fight malnutrition and health issues was highlighted.

Começo por traçar um quadro geral do que tem sido a investigação acerca das concepções, crenças e práticas dos professores da nossa disciplina, debruçando-me principalmente sobre os estudos feitos em Portugal. De seguida abordo os saberes que permitem o desempenho da sua actividade docente como o processo de criação desses mesmos saberes. Concluo indicando que um programa de investigação perspectivado em torno do saber prático e da reflexão poderá ajudar a ultrapassar a visão do professor como um profissional mais ou menos “carente” em relação às concepções e práticas apontadas como “correctas” pelas autoridades educativas. Ele poderá emergir como um actor pensante e actuante, dotado de uma intencionalidade e de um saber próprios, que em cada momento procura usar da melhor forma os meios à sua disposição para criar, conduzir e aperfeiçoar oportunidades de aprendizagem e de desenvolvimento pessoal e profissional.

For some wild canids, such as the Iberian wolf, there is a lack of in-depth knowledge about dental pathology. We aimed to evaluate it, in a standardized manner, in specimens from a Portuguese museum collection. Sixty-five deceased specimens of wild Iberian wolves, 61 complete skulls and 4 mandibles, collected in Portugal between 1977 and 1995, were analyzed. Sample comprised 18 females, 24 males and 23 individuals of undetermined sex. Teeth were evaluated by visual observation and dental radiography for tooth wear, periodontitis, fractures and other dental lesions. We have found several causes for teeth absence: artefactual, secondary to periodontitis and agenesia. About 30% of the teeth showed signs of wear. Only a small (<13%) fraction of maxillary and mandibular teeth did not show periodontitis. The tooth 308 showed periodontitis in all males (p = 0.017) and the tooth 104 was significantly affected by this condition in females (p = 0.020). A significant relationship was found between females and tooth wear in three teeth. Periodontitis showed a significant association with tooth wear (p < 0.001) and fractures (p = 0.027). Tooth fractures were more frequent in the maxilla than in the mandible. Seven periapical lesions, seven root fusions and three specimens with malocclusion were identified in the collection. Results are discussed integrating information from diet, habitat, genetic and spatial behavior. Dental radiography is here proposed as an approach for the age estimation in archaeological canids. This research contributes to the knowledge of the dental disease in the largest wolf population in Western Europe, a target subspecies of multiple conservation measures.

A valuable strategy to support conservation planning is to assess knowledge gaps regarding primary species occurrence data to identify and select areas for future biodiversity surveys. Currently, increasing accessibility to these data allows a cost-effective method for boosting knowledge about a country's biodiversity. For understudied countries where the lack of resources for conservation is more pronounced to resort to primary biodiversity data can be especially beneficial. Here, using a primary species occurrence dataset, we assessed and mapped Mozambique's knowledge gaps regarding terrestrial mammal species by identifying areas that are geographically distant and environmentally different from well-known sites. By comparing gaps from old and recent primary species occurrence data, we identified: (i) gaps of knowledge over time, (ii) the lesser-known taxa, and (iii) areas with potential for spatiotemporal studies. Our results show that the inventory of Mozambique's mammal fauna is near-complete in less than 5% of the territory, with broad areas of the country poorly sampled or not sampled at all. The knowledge gap areas are mostly associated with two ecoregions. The provinces lacking documentation coincide with areas over-explored for natural resources, and many such sites may never be documented. It is our understanding that by prioritising the survey of the knowledge-gap areas will likely produce new records for the country and, continuing the study of the well-known regions will guarantee their potential use for spatiotemporal studies. The implemented approach to assess the knowledge gaps from primary species occurrence data proved to be a powerful strategy to generate information that is essential to species conservation and management plan. However, we are aware that the impact of digital and openly available data depends mostly on its completeness and accuracy, and thus we encourage action from the scientific community and government authorities to support and promote data mobilisation.

Phenotypic plasticity can help organisms cope with changing thermal conditions and it may depend on which life-stage the thermal stress is imposed: for instance, exposure to stressful temperatures during development can trigger a positive plastic response in adults. Here, we analyze the thermal plastic response of laboratory populations of Drosophila subobscura, derived from two contrasting latitudes of the European cline. We measured reproductive performance through fecundity characters, after the experimental populations were exposed to five thermal treatments, with different combinations of developmental and adult temperatures (14°C, 18°C, or 26°C). Our questions were whether (1) adult performance is changed with exposure to higher (or lower) temperatures during development; (2) flies raised at lower temperatures outperform those developed at higher ones, supporting the “colder is better” hypothesis; (3) there is a cumulative effect on adult performance of exposing both juveniles and adults to higher (or lower) temperatures; (4) there is evidence for biogeographical effects on adult performance. Our main findings were that (1) higher developmental temperatures led to low reproductive performance regardless of adult temperature, while at lower temperatures reduced performance only occurred when colder conditions were persistent across juvenile and adult stages; (2) flies raised at lower temperatures did not always outperform those developed at other temperatures; (3) there were no harmful cumulative effects after exposing both juveniles and adults to higher temperatures; (4) both latitudinal populations showed similar thermal plasticity patterns. The negative effect of high developmental temperature on reproductive performance, regardless of adult temperature, highlights the developmental stage as very critical and most vulnerable to climate change and associated heat waves.

O primeiro episódio psicótico é uma síndrome variável que se define pela presença de sintomas positivos e negativos com uma duração contínua mínima de uma semana. Tipicamente tem início na adolescência e idade adulta jovem. A prevalência do uso de tabaco em doentes com primeiro episódio psicótico é marcadamente elevada, cerca de 59%, superior comparativamente à da população em geral. A maioria dos estudos existentes atualmente refere-se a doentes com doença psicótica crónica. Desta forma, tem-se manifestado interesse em entender a origem concreta da relação entre o tabaco e o primeiro episódio psicótico. Esta revisão sistemática reuniu os estudos publicados até março de 2018, através da pesquisa nas bases de dados Pubmed e Web of Knowledge, sobre a relação referida de forma a estudar três tópicos principais que poderão contribuir para a associação entre o tabaco e o primeiro episódio psicótico: 1)Tabaco como fator de risco do primeiro episódio psicótico; 2)A exposição à nicotina, através do tabaco, como comportamento de auto-medicação, e 3)Tabaco como marcador de gravidade da doença. Foram incluídos dez artigos originais, dos quais: um estudou o primeiro tópico acima referido; quatro estudaram o segundo; e os restantes cinco estudaram a terceira hipótese. Esta revisão permite concluir que a relação entre o tabaco e o primeiro episódio psicótico é inegável, e, apesar de ser dificil de alcançar a verdadeira génese da mesma, houve uma tendência para mostrar uma maior contribuição da hipótese “Tabaco como fator de risco do primeiro episódio psicótico” em relação à hipótese “A exposição à nicotina, através do tabaco, como comportamento de auto-medicação”. A última hipótese “Tabaco como marcador de gravidade da doença” foi aquela que mais foi corroborada, com quatro dos cinco estudos incluídos neste tópico a apoiar esta hipótese. Num dos estudos, sugere-se que a fraca adesão à medicação possa ser um fator causal que medeia a associação entre o tabaco e uma maior severidade da doença. Constatou-se, desta forma, que, apesar de serem necessários mais estudos sobre estas associações, no caso de serem totalmente provadas, poderão ter uma utilidade clínica muito vantajosa, primeiramente, numa perspetiva de prevenção e ainda no estadiamento da doença.

The flora and vegetation of the archipelago of Cabo Verde is dominated by Macaronesian, Mediterranean, and particularly by African tropical elements, resulting from its southernmost location, when compared to the other islands of the Macaronesia (i.e., Azores, Madeira, Selvagens, and Canary Islands). Very likely, such a geographical position entailed higher susceptibility to extreme climatic fluctuations, namely those associated with the West African Monsoon oscillations. These fluctuations led to a continuous aridification, which is a clear trend shown by most recent studies based on continental shelf cores. Promoting important environmental shifts, such climatic fluctuations are accepted as determinant to explain the current spatial distribution patterns of taxa, as well as the composition of the plant communities. In this paper, we present a comprehensive characterization of the main plant communities in Cabo Verde, and we discuss the role of the climatic and topoclimatic diversity in shaping the vegetation composition and distribution of this archipelago. Our study reveals a strong variation in the diversity of plant communities across elevation gradients and distinct patterns of richness among plant communities. Moreover, we present an overview of the biogeographical relationships of the Cabo Verde flora and vegetation with the other Macaronesian Islands and northwestern Africa. We discuss how the distribution of plant communities and genetic patterns found among most of the endemic lineages can be related to Africa’s ongoing aridification, exploring the impacts of a process that marks northern Africa from the Late Miocene until the present.

Biological collections, including herbarium specimens, are unique sources of biodiversity data presenting a window on the history of the development and accumulation of knowledge of a specific geographical region. Understanding how the process of discovery impacts that knowledge is particularly important for oceanic islands which are often characterized by both high levels of endemic diversity and high proportions of threatened taxa. The archipelagos of the Macaronesian region (i.e. Azores, Canaries, Savages, Madeira, and Cabo Verde) have been the focus of attention for scientific expeditions since the end of the 17th century. However, there is no integrated study describing the historical process of collecting, discovery and description of its flora. Using as a case study the Cabo Verde endemic angiosperm flora, we review the history of collecting in the flora and apply a Bayesian approach to assess the accumulation of species discovery, through time and space across the nine islands of the archipelago. Our results highlight the central role not only of natural characteristics (e.g. area, age, maximum altitude and average value of the terrain ruggedness index) but also historical factors (i.e. the location of major harbors) for the development of knowledge of the flora. The main factors that have determined the process of species description in the archipelago and how this impact our understanding of diversity patterns across archipelagos are discussed.

The Siam weed, Chromolaena odorata (L.) R. M. King & H. Rob. (Asteraceae), is recognized as one of the world’s worst tropical weeds. It is a perennial herb or shrub native to the neotropics that has become invasive across the tropical regions of Africa, Asia and Oceania. The species was introduced in 1937 in Nigeria and later spread to neighboring countries. Its presence and effects have been documented in the upland zones of almost all West African countries. Although, until the present study, the species had not been recorded in Guinea-Bissau, its presence in the country was very likely. In this work we document, for the first time, the invasion of Guinea-Bissau by C. odorata, assessing its present distribution and reporting effects, local uses and common names. Dispersal trends, potential consequences of its expansion and recommendations for management and control are also presented.