RCAAP Repository

Purpose: Despite recommendations, uncertainty results are rarely incorporated in Life Cycle Assessment (LCA) studies, especially regarding characterization factors (CF). Part 1 of this study conducted AWARE CF regionalization for Brazil, concluding that the Semiarid region had maximum scarcity values. The goal of this study is to evaluate the uncertainties of regionalized AWARE CF in the Semiarid region. Methods: Data used to obtain the AWARE BR CF for Brazil were qualitatively and quantitatively assessed. An adapted Pedigree Matrix was adopted to assess qualitative uncertainties. Classical statistical analysis was used for quantitative uncertainty assessment, and 10,000 Monte Carlo simulations were computed for uncertainty propagation. Results and discussion: Qualitative results indicated that the natural flow’s parameter was very uncertain due to poor spatial correlation and low reliability, as it is based on empirical models. Quantitative results showed that water availability data, which had large temporal variability, typical of the Brazilian Semiarid region, was the main responsible for uncertainties in input data. Area uncertainty had a good performance in both qualitative and quantitative assessments. Regarding output data, moderate CF were found to be more uncertain, while more extreme CF exhibited lower variation, corroborating with previous analyses. Moreover, the adoption of shorter datasets led to a reduction in average and standard deviation values for CF. Conclusion: Findings from this study showed two important reasons why the quantitative and qualitative assessments should be conducted simultaneously. The first one was to avoid bias, as availability data and natural flow performed differently in each evaluation. The second one was to confirm results, as the area proved to be very little uncertain in both assessments. An adaptation of Pedigree Matrix and a penalty factor for missing data could be used as a base for quantitative uncertainty parameters for LCIA. Generating SD and k-factor was very positive in terms of results for AWARE method and comparison with other methods. Both indicators had similar results and led to a common conclusion: uncertainties are mainly low and very low for AWARE BR CF in the Semiarid region.

Integrated assessment (IA) modelling can be an effective tool to gain insight into the dynamics of coupled earth system (land use, climate etc.) and socio-economic components. Quantifying and communicating uncertainties is a challenge of any scientific assessment, but is here magnified by the complex and boundary-crossing nature of IA models. Understanding the dynamics of coupled earth and socio-economic systems require data and methods from multiple disciplines, each with its own perspective on epistemological uncertainties (parametric and structural uncertainties), and its own protocols for assessing uncertainty. During the Paris Agreement, the lack of uncertainty analyses (UA) in IAs was risen (Rogelj et al. 2017) and calls for close collaboration of scientists coming from different fields. In this study, we review how uncertainties are tackled in a range of science disciplines that are related to global change including climate, hydrology, energy and land use, and which contribute to IA modelling. We conducted a meta-analysis to identify the contributing disciplines, and review which type of uncertainties are assessed. We then describe sources of uncertainty (e.g. parameter values, model structure), and present opportunities for improved assessment and communication of uncertainties in IA modelling. We show in our meta-analysis that parametric uncertainty is the uncertainty analysis that has been applied the most, while structural uncertainty is less commonly applied, with the exception of the energy scientific discipline. We finish our study with key recommendations to improve uncertainty analysis such as including risk analysis. By embracing uncertainties, resilient and effective solutions for climate change mitigation and adaptation could be better communicated, identified and implemented.

When growing microalgae for biorefinery processes, a high product yield is desired. For that reason, monitoring the concentration of the desired products during growth and products induction procedure is of great interest. 2D Fluorescence spectroscopy is a fingerprinting technique, used in situ and at real time, with a high potential for online monitoring of biological systems. In this work, Dunaliella salina pigment content was monitored using fluorescence data coupled with chemometric tools. Climatic parameters were also used as input variables due to their impact on the pigments profile in outdoor cultivations. Predictive models were developed for chlorophyll content (a, b, and total) with variance captured between 50 and 90%, and R2 varying between 0.6 and 0.9 for both training and validation data sets. Total carotenoids models captured 70 to 80% of variance, and R2 between 0.7 and 0.9, for training and validation. Models for specific carotenoids (zeaxanthin, α-carotene, all-trans-β-carotene, and 9-cis-β-carotene) captured variance between 60 and 90%, with validation and training R2 between 0.6 and 0.9. With this methodology, it was possible to calibrate a monitoring tool for pigments quantification, as a bulk and as individual compounds, proving that 2D fluorescence spectroscopy and climatic data combined with chemometric tools can be used to assess simultaneously and at real time different pigments in D. salina biomass production.

Mangrove forests are among the most productive ecosystems on Earth. However, there is still insufficient information available for strategic prediction of conservation and management intervention, particularly in the case of Mozambique. This country has the longest coastline and mangrove forests of Eastern Africa, but is prone to global climate hazards. Using recent field data and environmental parameters subjected to the Variance Inflation Factor (VIF) collinearity test (bioclimatic variables, slop, salinity, land cover, and elevation), we ran MaxEnt to model the distribution of mangrove forests based on occurrence data of the most emblematic and representative mangrove species in Mozambique (Avicennia marina and Rhizophora mucronata). Moreover, in order to understand which areas should be prioritized for management interventions on mangroves and costal dunes, an Exposure Index (EI) to climate hazards and erosion was compared with the potential distribution of these species. Our results showed that average wind speed of summer season, land surface elevation, Mean Diurnal Range, and saltwater exposure (salinity) were determinant on the distribution models of both species. The central coastal region of Mozambique (so-called swamp coast) presents the largest potentially suitable areas for mangroves species occurrence, having the highest levels of exposure. We also found that A. marina presents a higher EI than R. mucronata. The scarcity of studies concerning the central region of Mozambique; which was recently devastated by cyclone Idai (category four, 2019), which hit Mozambique and the neighbouring countries, reinforce the urgency for management intervention. The findings of this study should be used by managers and decision makers to promote best practices to safeguard lives and people's livelihoods and assets threatened by coastal climate hazards and anthropogenic impacts.

We assessed the spatial extent at which the species-landscape relationship is strongest (i.e. the scale of effect—SE) on primate occurrence (Alouatta belzebul, Saguinus midas, Saimiri sciureus, and Sapajus apella and Cebus olivaceus, the last two considered together in the analysis) and species richness and evaluated which landscape, patch, and human variables influence primate distribution in a savanna ecosystem in Brazil. We used nested buffers to measure the landscape attributes, and used these data to assess the SE of the species-landscape relationships. We explored the relative contributions of landscape, patch, and human variables to species richness and occurrences by using Generalized Linear Mixed Models and logistic regression. We found that the SE did not differ between primates, but did between two regions with different matrix composition. At the landscape level, occurrence of all species was higher as the distance to the nearest block of continuous forest decreased, but was lower as the amount of water bodies and anthropogenic cover in the matrix increased. The occurrence of S. apella, C. olivaceus and A. belzebul was positively related to forest cover, and all species but A. belzebul had higher occurrence in taller forest. The occurrence of S. apella, C. olivaceus and A. belzebul decreased closer to the city, and S. apella and C. olivaceus presence increased with the number of residents. Richness was negatively related to the number of residents and anthropogenic cover, but positively to forest height. We concluded that conservation planning for primates should follow a “functional landscape” perspective, by maintaining higher forest cover and minimizing the anthropogenic alterations in the matrix.

Drawingvoice 2.0 is an instructional method of collaborative pencil and paper drawing to use in the school classroom, followed by Facebook interaction on the drawing produced in class. It is based on a participatory and meta reflective approach, explicitly aimed at deconstructing, negotiating, and reconstructing the meaning that students attribute to themselves regarding their professional expectations and educational pathways. In particular, the collaborative pencil and paper drawing allows for the student’s emotional symbolisation processes underlying their educational pathway. Drawingvoice 2.0 induces a multidimensional cognitive and meta-cognitive process further supported by the following interaction on Facebook. Therefore, the World Wide Web is the added resource for sharing and deepening the classmates’ discussion. Finally, Drawingvoice 2.0 supported structural group interaction and was an important supportive and instructional method to bring about transformational and developmental training practices. As the main result, in our experience, psychology students increased their reflectivity about their strengths and threats in being psychologists within their cultural contexts and potential positive resources underlying their choice. Drawingvoice 2.0 thus enhanced their self-awareness about the lights and shadows of their training and future professional career.

Circular RNAs are a large group of non-coding RNAs with a closed-loop structure. circRNAs play significant roles in many biological processes as miRNA sponges, regulators for gene transcription, combining with RNA-binding proteins and translation of protein. Nowadays, circRNAs have become a research hotspot in the field of cancer and molecular biology. Accumulating evidences have indicated that circRNAs participate in the initiation and development of various cancers such as breast cancer. Breast cancer is a heterogeneous disease, which is the most common malignancy in women. The incidence and mortality rates of breast cancer indicate that it is the leading cause of cancer-related deaths. The goal of the present review is to introduce biogenesis, function characteristics and types of circRNAs, and also their biological functions on breast cancer, especially as miRNA sponges. Additionally, we discuss their use as a new therapeutic target for the treatment of breast cancer.

Studies concerning young-adult amyotrophic lateral sclerosis (yALS) are uncommon, due to the rarity of this condition. We aimed to investigate this subject. Methods: A retrospective-prospective study was conducted in our ALS center, including 1278 ALS patients followed longitudinally. Patients were divided in two groups - yALS (onset ≤40 years) and adult-onset ALS (aALS, onset >40 years). We analyzed phenotype, survival and genetics. Results: Sixty-three out of 1278 (4.9%) patients were included in yALS group, while the majority were categorized as aALS (1215, 95.1%). Juvenile ALS (onset < 25 years) represented 14.3% (9 patients) of yALS. In yALS group mean onset age was 32.5 ± 6.6 years (14-40) and 68.3% were men. Spinal-onset was significantly more frequent in yALS (p < 0.001), while bulbar-onset was more common in aALS (p = 0.002). Diagnostic delay was longer in yALS group (p = 0.02). yALS patients survived longer than aALS (88.2 ± 81.9 versus 41.1 ± 34, p < 0.001), and functional decay was the only independent predictor found in the younger group (p = 0.007). No other significant differences were found, including familial history of ALS. Three yALS patients (4.8%) had C9orf72, SOD1 and FUS mutations identified by single-gene testing. A panel of 50 ALS-related genes investigated with next-generation sequencing in 9 yALS patients revealed no pathogenic mutation. Conclusions: yALS is a rare and specific ALS group. Disease progression is slower and survival longer in yALS, moreover and bulbar-onset phenotype is less common than in aALS. These observations are relevant to inform patients and for clinical trials design.

Juvenile gangrenous vasculitis of the scrotum is a rare entity of unknown aetiology which should be considered in the differential diagnosis of genital ulcers, mainly with those caused by sexually transmitted infections. The authors report a case of a 23-year-old patient who presented a single painful scrotal ulcer developing shortly after an episode of pharyngotonsillitis. The ulcer was treated with oral corticosteroids with total healing and no relapse in over two years of follow-up.

No summary/description provided

It has been well documented that Zika virus (ZIKV) can be sexually transmitted. Dengue virus (DENV) shows many similarities with ZIKV; both belong to the genus Flavivirus and share the same main vector route of transmission. Moreover, they share overall architectural features on a molecular level, with a highly similar structure and distinctive insertions, deletions and mutations of their respective E proteins, and it has been suggested that they use a common pathophysiological pathway. In view of similarities with other sexually transmissible viruses, the question arises as to whether DENV could also be sexually transmissible. Limited animal model data do not suggest otherwise. The presence of dengue virus in - and human-to-human, non-vector transmission from - various bodily fluids other than semen or vaginal secretions has been documented anecdotally. Several anecdotal reports described prolonged presence of DENV in semen, urine and vaginal secretions. In 2019, two cases of likely sexual transmission were reported from Spain and South Korea, respectively. We discuss the evidence for and against a relevant DENV sexual transmission potential, highlight controversies and propose a future research agenda on this issue.

Os estudos de dieta são um elemento importante na compreensão da ecologia de uma espécie, mas são muitas vezes negligenciados e a sua importância subestimada. A dieta de um organismo permite conhecer o habitat em que o animal vive e as suas adaptações ao meio ambiente, mas também permite saber sobre interações com outras espécies. É a combinação de estudos de dieta de várias espécies que permite construir cadeias alimentares e compreender a estrutura e o funcionamento dos ecossistemas. A aplicação deste tipo de estudos no meio marinho tem importância acrescida, uma vez que estudos baseados em observação directa não são suficientes. Esta importância é ainda mais acentuada nas regiões oceânicas, onde as densidades de organismos são baixas e o seu estudo é um desafio. Esta tese tem como objetivo estudar a dieta e as relações tróficas entre os predadores de topo e as suas presas na região oceânica do arquipélago da Madeira. A dieta e as áreas de alimentação de espécies de importância ecológica e económica, como atuns, aves marinhas e pequenos peixes pelágicos, foram estudadas na tentativa de compreender a sua posição e o seu papel na cadeia alimentar deste ambiente oceânico. A dieta de duas espécies de peixes pelágicos, a cavala Scomber colias e o carapau-negrão Trachurus picturatus, foi analisada com base na identificação do conteúdo estomacal de indivíduos capturados ao longo de um ano, nas proximidades da ilha da Madeira. Ambas as espécies são planctívoras e piscívoras, alimentando-se sobretudo de copépodes calanóides e ciclopóides, e de pequenos agulhões Scomberesox saurus, clupeídeos, apara-lápis Macroramphosus scolopax e mictofídeos. A dieta do patudo Thunnus obesus e do gaiado Katsuwonus pelamis, foi estudada identificando o conteúdo estomacal de indivíduos apanhados na Madeira e confirmada através da análise de mercúrio nos tecidos dos atuns e de outros dois peixes epipelágicos, a bicuda Sphyraena viridensis e o charuteiro Seriola rivoliana. A dieta de ambas as espécies de atum é composta principalmente por espécies epipelágicas, como a cavala e o peixe-rei Atherina sp., o que contrasta com o comportamento e dieta mesopelágicos do patudo em outras regiões do mundo. Também investigámos a utilização de recursos marinhos pela gaivota-de-patas-amarelas Larus michahellis atlantis no arquipélago da Madeira. Esta ave costeira mostrou uma grande dependência antropogénica, com elevado uso de ambientes terrestres e associados ao homem. As poucas vezes que utilizou o meio marinho foi, principalmente, à noite e em associação com embarcações de cerco. A sua dieta refletiu este comportamento, sendo maioritariamente composta por resíduos e alguns peixes. O estudo da variação na composição de espécies epipelágicas na vasta região da corrente das Canárias, foi realizado utilizando as aves marinhas como indicadores. Com recurso a viagens de alimentação e regurgitos de cagarras Calonectris borealis a nidificar nas Ilhas Selvagens, recolhidos por um período de sete anos, este estudo conseguiu detetar uma alteração na comunidade de peixes pelágicos, com um aumento acentuado da população de apara-lápis nos arredores das ilhas Selvagens, em 2017/2018. Por fim, desenvolvemos um modelo baseado no equilíbrio de biomassas de espécies encontradas na Zona Económica Exclusiva do arquipélago da Madeira, utilizando o software Ecopath with Ecosim. Este capítulo reuniu as informações recolhidas nos outros capítulos e juntou-as aos dados disponíveis na literatura. O nosso modelo estimou uma elevada biomassa de produtores primários, zooplâncton, outros crustáceos e invertebrados, mas também de pequenos peixes pelágicos e mesopelágicos, que foram considerados o principal alimento de predadores de topo. O ecossistema caracterizou-se por um baixo número de ligações entre os níveis tróficos, que está relacionado com uma dieta mais especializada por parte de organismos como golfinhos, aves marinhas e grandes peixes pelágicos. Apesar de o ecossistema ter apresentado um nível trófico médio baixo, o nível trófico das pescas foi bastante alto por, na Madeira, predadores de topo como atuns e peixe-espada, serem os mais pescados. Os predadores de topo também foram considerados importantes modeladores do ecossistema, sendo designados por espécies-chave.

Unveiling how genetic diversity and structure of high mountain populations evolved and what factors are currently shaping it is crucial to predict how species will respond to threats such as climate change, and this will ultimately help to design species-specific conservation measures. Therefore, an integrative approach that combines the study of phylogeographic processes and contemporary dispersal dynamics is required to shed light on the mechanisms underlying spatial patterns of present-day genetic diversity and population structure, which can help to predict species responses to ongoing or future environmental changes. The general aim of this thesis was to uncover major historical and contemporary factors explaining the current genetic diversity and structure of selected Iberian amphibians living in high mountains, namely the Pyrenean brook newt, Calotriton asper, and the midwife toads of the Alytes obstetricans complex. I integrated various techniques, including genetic and mark-recapture analyses, to provide new insights into the phylogeographic history of the study species, describe the genetic consequences of chytridiomycosis outbreaks in midwife toads, inform on current connectivity in C. asper, and characterize its process of lake recolonization following invasive fish removal. Specifically, I showed that C. asper likely endured the last glaciation in five distinct glacial refugia across the Pyrenees, and I detected evidence of extensive mito-nuclear discordances and admixture between taxa of the A. obstetricans complex across three Iberian mountain ranges. A. obstetricans populations hit by a relatively recent chytridiomycosis outbreak had a reduced effective size and were depleted of genetic diversity. Finally, although I found that the majority of C. asper dispersal events involved geographically close populations, I also found potential for occasional long-distance dispersal and revealed the importance of neighbouring fishless areas as source of individuals for restored lakes. Overall, the results of this thesis contribute to improve our understanding of the factors responsible for species structuring in high mountains and may be useful to guide future management decisions for C. asper and the A. obstetricans complex.

This thesis deals with extensions of General Relativity and their application to Cosmology and Gravitation. The introduction and main motivations of this essay can be found on Chapter 1. The second chapter proposes a dark energy model driven by a scalar field kinetically coupled to matter. The dynamics of the system are analysed through dynamical systems techniques. The background is evolved and the solutions are meticulously studied, focusing on the influence of the coupling on the cosmological parameters. Through the Planck constraints, it is derived anupper bound on the coupling parameter. Chapter three is devoted to the analysis of a conformally coupled quintessence model in which the background expansion is set to mimic a CDM evolution. Both the background and linear perturbations are analysed. The growth of structures is tested against redshift space distortions data. The spherical collapse and cluster number counts are explored, and we shed some light on the possibility to distinguish between theoretical models with regard to two surveys. An alternative formulation of General Relativity, where gravity is mediated by nonmetricity, on a flat and torsion free spacetime is exposed on the fourth Chapter. The background dynamics are set to follow the same evolution as in the standard model of Cosmology. The linear matter perturbations are evolved and the f 8 parameter is tested against large scale observations in the late Universe. Chapter five introduces a 3-form field to the Einstein-Hilbert action in the context of gravitation. Specifically, it is found wormhole solutions where the ordinary matter fields are able to coexist throughout spacetime without violating the classical energy conditions. On such scenario, the 3-form field is responsible for holding the throat of the wormhole open. On Chapter six the gravitational Lagrangian for modified Gauss-Bonnet gravity is reconstructed, such that the Friedmann equation of a bouncing Universe is recovered.

Esta tese estuda a pratica e o ensino da astrologia pela Companhia de Jesus nos seculos XVI, XVII e principio do XVIII. Numa primeira analise esta ligação parece inesperada pois a astrologia não era vista favoravelmente pela Igreja e os Jesuítas, uma das ordens mais poderosas da contrarreforma, e firmes defensores da ortodoxia. Com base nesta premissa, muitos historiadores assumiram que o fervor religioso dos jesuítas seria acompanhado por uma igualmente intensa rejeição da astrologia. Esta noção era aparentemente consolidada por publicações anti-astrológicas de autores da Companhia. No entanto, um estudo detalhado de textos e ensinamentos jesuítas sobre a astrologia revelam uma atitude de maior aceitação deste assunto. Este estudo mostra que embora alguns membros da Companhia tivessem uma postura anti-astrológica de base religiosa, outros aceitavam-na como um conhecimento valido, compatível com os limites estabelecidos pela teologia tomista e pelas regras do Índex e das bulas papais (1586 e 1631). Esta aceitação da astrologia e mais evidente entre os astrónomos jesuítas, que a consideravam parte do corpus cientifico pré-moderno, no contexto das ciências matemáticas. Embora presente de forma mais discreta nos textos impressos, e no corpus de manuscritos científicos jesuítas que esta postura se torna plenamente evidente. No centro do presente estudo estão as sebentas de astrologia lecionadas na Aula da Esfera do Colégio de Santo Antão, uma das principais instituições Jesuítas de ensino em Portugal. Aqui a astrologia foi ensinada em conjunto com outras ciências matemáticas, como a astronomia e a navegação. Paralelamente a estas lições foram também analisados outros documentos astrológicos jesuítas originários da Europa, do Extremo Oriente e do Novo Mundo. Este grupo documental permitiu uma visão detalhada das relações dos jesuítas com a astrologia, incluindo textos defendendo a sua pratica, um currículo jesuíta de astrologia ajustado a pratica religiosa, e vários exemplos de julgamentos astrológicos feitos por membros da Companhia. A primeira parte da tese oferece uma visão da astrologia neste período: a sua pratica, as mudanças e divulgação impulsionadas pelo advento da imprensa, os grandes debates antiastrológicos, e a crescente marginalização no final do seculo XVII. Na segunda parte são abordadas as opiniões dos Jesuítas em relação ao tema: os textos anti-astrológicos, os argumentos teológicos e o seu posicionamento no discurso cientifico pela voz dos matemáticos e astrónomos da Ordem. A terceira parte aborda as lições de astrologia da Aula da Esfera do Colégio de Santo Antão, demonstrando que estas faziam claramente parte do currículo publico do colégio. Em seguida e apresentado um estudo detalhado do programa das aulas de astrologia, revelando as suas especificidades cientificas e adequação religiosa. A quarta e ultima parte apresenta alguns exemplos de juízos astrológicos por autores jesuítas demonstrando que o seu uso da astrologia não se restringia a reflexão teórica e ao ensino, estendendo-se também a prática. Desta analise resulta uma nova visão da relação dos jesuítas com a astrologia, colocando esta pratica como parte integrante do corpus de conhecimentos estudados pela ciência jesuíta.

O acesso à eletricidade está associado à melhoria dos meios de subsistência, educação, saúde, crescimento económico e redução geral da pobreza. A grande maioria das pessoas que vivem sem, ou com acesso não fiável, a energia elétrica encontra-se na África subsaariana e sudeste asiático. Apesar de ser a maior economia de África, a Nigéria sofre de problemas graves de cortes frequentes de energia, obrigando muitos residentes a procurar opções de auto-geração, sobretudo geradores a diesel, com custos de investimento inicial relativamente baixo, mas que trazem riscos à saúde e ao meio ambiente. Uma alternativa viável são os sistemas fotovoltaicos; no entanto, o investimento inicial é muito maior em comparação com os geradores a diesel, criando uma barreira para muitos nigerianos. A primeira parte desta tese explora a opção de geração de eletricidade solar em ambiente urbano, mais limpa e mais acessível, aumentando o acesso fiável a eletricidade e reduzindo, ou eliminando, o uso de geradores a diesel. Propõe-se um caminho para a implementação em larga escala de sistemas fotovoltaicos domésticos em ambiente urbano, com o custo coberto pela poupança de combustível, possibilitado por uma política eficaz que melhora o acesso a opções de financiamento. Aproveitando dados reais de uma campanha de monitorização de consumo de eletricidade em Lagos, o centro comercial da Nigéria, os resultados mostram uma oportunidade para reduzir ou eliminar o uso de geradores a diesel aplicando a poupança de custos de combustível para financiar sistemas fotovoltaicos. A segunda parte desta tese trata do setor comercial, que tem sido significativamente prejudicado pela pouca disponibilidade de eletricidade confiável. Quase metade das empresas na Nigéria identificou a eletricidade como um grande obstáculo, com mais de um quarto delas apresentando a eletricidade como maior obstáculo. As perdas comerciais devido a interrupções elétricas são significativas, com perdas médias estimadas de cerca de 16% das vendas anuais. A falta de acesso a eletricidade confiável é um dos maiores desafios para o crescimento económico na Nigéria. É proposto um meio de fornecer energia ao setor comercial através de eletrificação solar por enxame (swarm). É descrita uma estrutura conceitual para o uso de uma rede distribuída composta de sistemas fotovoltaicos domésticos ligados à rede como uma opção viável para fornecer ao setor comercial um acesso mais confiável à eletricidade. Finalmente, são abordadas as implicações de política para o setor comercial com mais opções de eletrificação, implicações que incluem um forte impacto económico e a expansão e criação de novas indústrias.

The marine environment is affected by multiple natural drivers and anthropogenic stressors that can have a strong impact on the sustainability of marine ecosystems and resources. Understanding the marine environment dynamics, in its various aspects, has therefore become a worldwide priority to the study of the sedimentary cover. Understanding of its spatial and temporal patterns, can be of critical importance for resource management, environmental protection initiatives and effective marine governance. The present work aims at the study of the sedimentary processes affecting the Estremadura Spur in order to understand its evolution of marine systems in an environmental and climate change context. With this goal, a multidisciplinary approach will attain the different aspects of marine processes on the Estremadura Spur continental shelf. With a triangular shape, the Estremadura Spur is a prominent geomorphological unit that stands out from the general morphology of the West Iberian Peninsula. This sector is isolated from the nearby sectors by the northern Nazaré Submarine canyon and the Lisboa Canyon in the south. The Estremadura Spur continental shelf has variable width, ranging from 15 km (in front of Peniche) to 70 km (in Ponta da Lamparoeira parallel) and its external border (shelf break) is located at variable depth, ranging from ~50 m to more than ~300 m. The continental shelf is characterized by large areas of carbonated rocky outcrops and a thin layer of unconsolidated sediments and the coastal zone is predominantly composed by rocky cliffs with few embayed beaches, closer to the mouth of small rivers and creeks. This sector of the Portuguese shelf is affected by a high energetic wave regime that dominates inner and middle shelf sediment dynamics. At the outer shelf and upper slope, oceanographic phenomena, like internal waves, have been recognized to occur, which impact particle resuspension and transport. In the Portuguese continental shelf, during the winter, the predominant current direction is northward; however, during the three months period of in situ observations (winter time), in the outer shelf of the Estremadura Spur, the dominant current direction was oriented southward, inducing a particle transport with the same direction; the observed residual current from current meter data ranged from 0 to 13 cm/s. Two main components were identified, namely cross-shelf and along shelf. As a result of this morphology and wave regime exposition, sedimentary patterns indicate that the contribution of recent sand terrigenous particles is only significant in the inner shelf. In the northern sector, the middle shelf is covered by very coarse deposits in the vicinity of extensive rocky outcrops. Immediately south of those outcrops, sediments become finer, with muddy sand deposits covering the entire Mar da Ericeira. Muddy sands also cover the outer domains of the Estremadura Spur, with a large elongated sandy deposit located along the outer shelf. Sedimentary particles from adjacent beaches and rivers that drain directly into the Estremadura Spur are mainly sand-sized. River sediments also have a significant component of fine particles, while the beach sediments have no fine fraction and gravel is only important at Foz do Arelho beach. There is no clear relationship between minerals present in the fine fraction of river sediments that drain to the Estremadura Spur and those found in the shelf. The high percentage of potassium feldspar and plagioclase near the coast can be explained by the proximity to the terrigenous particle sources (continental origin), while the other minerals seem to be related to the effect of distribution processes that control the distribution of the main mineral species. The riverine environment has clearly different assemblages of heavy minerals than the ones found on beaches and inner shelf. The heavy minerals highlight two distinct coastal sedimentary cells, characterized by distinct associations. The beach sediments present a similar heavy mineral content to inner shelf sediments, but the influence of the riverine/continental input is higher at the beaches, as demonstrated by high percentages of tourmaline and andaluzite in the north, and pyroxenes in the south. The analysis of present-day sedimentary dynamics revealed characteristics of wave/storm dominated continental shelf. Threshold orbital velocity near the bottom computed with SWAN, using 22 years of wave data, for coarse (0.500 mm) and fine particles (0.063 mm), show that coarse particles are remobilized more that 40 % of the time for depths up to 30 m and fine particles can be remobilized 50 % of the time till 40 m depth and 10 % of the time till 100 m. The sediment transport pathways over the Estremadura Spur, deduced from the GSTA (Grain Size Trend Analysis), indicate four different sectors in relation to distinct oceanographic, sediment supply and geomorphologic constraints. Due to lower sediment sampling resolution, GSTA was not able to resolve the sedimentary transport in the inner shelf sector. The study of a vertical sample collected offshore Ericeira (in the center of the largest muddy deposit of the Estremadura Spur) allowed the understanding of the environmental shelf changes during the Holocene, with impact on the sediment record. The oldest sedimentary sequence corresponds to a high energy environment, likely representing a coastal deposit in close connection to the terrigenous particle sources. The middle sedimentary sequence shows an increased presence of biogenic particles and a decrease in coarser particles indicating a deeper and lower energy environment, when compared with the older sequence. In the superficial sequence (which is only 20 cm thick), sediments are compatible with middle shelf dynamic processes very similar to present day characteristics. The sudden increase of heavy metals like mercury (Hg) and lead (Pb) can be explained by the increase of anthropogenic activity, either related to deforestation or mining. These activities increase soil erosion, leading to a characteristic inorganic detrital deposit in most aquatic systems (lakes, rivers and seas). The reconstruction of the evolution of the Estremadura Spur during the recent Quaternary was performed by the integration of morphological and sedimentological characteristics. As an important input to this model and to explain the origin of the three sedimentary sequences, additional radiocarbon analyses of benthic organisms were used as reference, as well as published sea level curves for the Portuguese continental shelf and other several studies on paleoreconstruction of the Portuguese margin. During the Last Glacial Maximum, the coastline was at ~ 130 m depth and the present day rivers were active valleys carrying sediment into the shelf break. During this period, the rocky outcrops at Ponta da Lamparoeira parallel, formed a morphological barrier between the northern and southern areas of Estremadura Spur. The sedimentation over the shelf was very scarce at this time due to the cold and arid conditions. In the beginning of the deglaciation (warmer climate), the coastline started to migrate landward and coastal areas were invaded by the sea up to ~ 110/100 m depth and sediment export increased quite slowly. At the end of the deglaciation the sea level rose very rapidly settling at ~ 50/40 m depth. This sudden sea level rise induced such an imbalance that estuaries became sediment traps and few sediments were able to reach the continental shelf, which resulted in a scarcity of sediments and the coastline maintained its rocky characteristics. During the Younger Dryas, the sea surface temperature dropped below 10 ºC and the relative mean sea level (rmsl) lowered 20 m in 1000 years. By the end of this event the msl was ~ 60 m depth. This new cycle induces the remobilization of coastal and estuarine particles deposited in the previous phase. In the Holocene, the establishment of a warmer period contributed to the multi-phase rise of the msl. These multi-phase events are represented by Early, Middle and Late Holocene. In the Early Holocene, the sea level rose almost 40 m in 2000 years, leading to thick transgressive sequences, due to the high levels of precipitation. At this time, the conditions were similar to those of an inner shelf like environment with high energy conditions. During the Middle Holocene, the overall conditions of sea level rise and rapid environmental conditions were maintained (msl rise ~15 m above present sea level). This period is represented in the sediment core as a ~ 80 cm thick layer, indicating a drastic decrease in energy conditions, concurrent with an increase of the living conditions represented by species diversity. In the Late Holocene, the msl settled at the present level. With the increasing human activity, with impacts on deforestation and mining processes, the presence of heavy metals in the sedimentary record also increases. A high fluvial/continental input was expected, with higher species diversity due to higher availability of nutrients and fine particles. Although the sediment input might have increased, the accumulation rate is still very low when compared to other sectors of the Portuguese continental margin.

The Alentejo Margin, in the Southwest Portuguese Continental Margin, is a very complex and dynamic geomorphological area, located near the Eurasia-Africa plate boundary and affected by the flow path of the Mediterranean Outflow Water (MOW). This margin comprises the Sines Contourite Drift (SCD), which is the most prominent depositional feature (~2311 km2, 303.9 km perimeter, 98 km length and 35 km width), emplaced in the continental slope of this margin, evolving in four main phases by the action of MOW, since the Late Pleistocene. The interaction between along-slope and downslope processes forms a mixed morphosedimentary setting, which is greatly affected by mass movement activity in the middle and lower continental slopes, during the Late Pleistocene-Holocene. This work analyses the occurrence of mass movement processes in the southwest Portuguese margin, in a total extent of ~85 km×82 km and identifies the main triggering and conditioning factors promoting slope instability during the Late Pleistocene-Holocene and assesses the morphosedimentary evolution of the Sines Contourite Drift. This study was performed through geophysical, sedimentological, physical, geochemical, and geotechnical analyses, using multibeam bathymetry, multichannel seismic and sub-bottom profiler, and gravity cores data. The Alentejo margin is an unstable area, where the presence of a contourite drift significantly contributes for slope instability in consequence of its sediment mechanical properties. The SCD hosts a cluster of dominantly small landslide scars, affecting both steep and smooth slopes. This scar concentration is mainly provided by local intrinsic conditions that favour slope instability in the area. Scars predominantly occur on slope angles steeper than 5º, however sediment properties, especially low consolidation, very low permeability, high pore-pressure, high compressibility and low shear strength greatly promote slope instability in the Alentejo Margin. The inherent instability conditions of the area are increased by frequent seismicity that promotes additional stress, leading to increased slope instability.

As zonas áridas estão a sofrer um aumento no grau de aridez e de pressões antropogénicas, que têm consequências socioeconómicas e ecológicas. As zonas áridas do Mediterrâneo parecem ser particularmente vulneráveis a aumentos de aridez, os quais têm colocado a sua biodiversidade e funcionamento em perigo. Para o estudo e monitorização das mudanças na biodiversidade em resposta a pressões ambientais, climaticas e antropogénicas, é essencial identificar indicadores ecológicos e as melhores métricas que refletem a mudança na diversidade. As formigas são importantes engenheiros do ecossistema e indicadores ecológicos; assim, entender as suas respostas às mudanças ambientais, a par da identificação das melhores métricas que refletem a mudança na diversidade, pode ajudar a prever o funcionamento dos ecossistemas, especialmente no contexto dos hotspots de biodiversidade, como é o caso do ecossistema Mediterrânico. O objetivo desta tese de doutoramento é i) avaliar quais são as variáveis ambientais que atuam em diferentes escalas espaciais sobre a biodiversidade das formigas, tanto ao nível da espécie como das características funcionais e ii) identificar quais são as métricas baseadas na espécie e nas suas características funcionais que são mais adequadas para seguir os efeitos das alterações ambientais em pequena e larga escala na biodiversidade das formigas. Para isso, selecionámos diferentes gradientes no ecossitema Mediterrânico, que incluem um gradiente de micro-escala floresta-prado, um gradiente de aridez espaço-por-tempo e uma sucessão pós-pastoreio. De um modo geral, constatámos que a estrutura local do habitat, as variáveis regionais climaticas e as pressões antropogénicas atuam sobre a biodiversidade das formigas a diferentes escalas, no espaço e no tempo. Em particular, os diferentes gradientes evidenciaram a forte associação entre as comunidades de plantas e de formigas e respetivas diversidades, em diferentes escalas espaciais. Os resultados foram concordantes sobre os impactos negativos de uma espécie invasora na biodiversidade de formigas e num processo do ecossistema, sugerindo que a restauração do ecossistema é necessária para promover a recuperação da biodiversidade de formigas e das funções do ecossistema mediados por este grupo-chave. Em relação às métricas utilizadas, os resultados enfatizam a importância de incluir diferentes abordagens (baseadas em espécies e características funcionais) para avaliar a resposta das formigas às mudanças ambientais. No entanto, os índices baseados em caraterísticas funcionais apresentaram melhor desempenho do que os índices taxonómicos, sugerindo a sua importância como indicadores ecológicos para monitorizar os efeitos das alterações ambientais em pequena e larga escala nas zonas áridas do Mediterrâneo.

The dissertation is based on examples of contemporary artists whose work is based on and around Marian iconography and their attempts to perpetuate and understand the mother-child relationship. The intention is to explore and explain art based on the mother figure (the symbol of love) and then reuse the sanctified image of the Mother; specifically the Virgin Mary which they believe is able to more easily reach a public set within a modern visual culture. Its reinterpretation allows entry into a universe which joins a visual domain with a creative one that in turn justifies a third: the spiritual. The underlying objective in the artistic process is to achieve a contemporary essence and spirituality in art and to understand the artistic ideas and processes of the artists investigated