852 resultados para Mortalidade materna


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Atualmente, a poluição atmosférica constitui uma das principais causas ambientais de mortalidade. Cerca de 30% da população europeia residente em áreas urbanas encontra-se exposta a níveis de poluição atmosférica superiores aos valores- limite de qualidade do ar legislados para proteção da saúde humana, representando o tráfego rodoviário uma das principais fontes de poluição urbana. Além dos poluentes tradicionais avaliados em áreas urbanas, os poluentes classificados como perigosos para a saúde (Hazard Air Pollutants - HAPs) têm particular relevância devido aos seus conhecidos efeitos tóxicos e cancerígenos. Neste sentido, a avaliação da exposição tornase primordial para a determinação da relação entre a poluição atmosférica urbana e efeitos na saúde. O presente estudo tem como principal objetivo o desenvolvimento e implementação de uma metodologia para avaliação da exposição individual à poluição atmosférica urbana relacionada com o tráfego rodoviário. De modo a atingir este objetivo, foram identificados os parâmetros relevantes para a quantificação de exposição e analisados os atuais e futuros potenciais impactos na saúde associados com a exposição à poluição urbana. Neste âmbito, o modelo ExPOSITION (EXPOSure model to traffIc-relaTed aIr pOllutioN) foi desenvolvido baseado numa abordagem inovadora que envolve a análise da trajetória dos indivíduos recolhidas por telemóveis com tecnologia GPS e processadas através da abordagem de data mining e análise geoespacial. O modelo ExPOSITION considera também uma abordagem probabilística para caracterizar a variabilidade dos parâmetros microambientais e a sua contribuição para exposição individual. Adicionalmente, de forma a atingir os objetivos do estudo foi desenvolvido um novo módulo de cálculo de emissões de HAPs provenientes do transporte rodoviário. Neste estudo, um sistema de modelação, incluindo os modelos de transporteemissões- dispersão-exposição, foi aplicado na área urbana de Leiria para quantificação de exposição individual a PM2.5 e benzeno. Os resultados de modelação foram validados com base em medições obtidas por monitorização pessoal e monitorização biológica verificando-se uma boa concordância entre os resultados do modelo e dados de medições. A metodologia desenvolvida e implementada no âmbito deste trabalho permite analisar e estimar a magnitude, frequência e inter e intra-variabilidade dos níveis de exposição individual, bem como a contribuição de diferentes microambientes, considerando claramente a sequência de eventos de exposição e relação fonte-recetor, que é fundamental para avaliação dos efeitos na saúde e estudos epidemiológicos. O presente trabalho contribui para uma melhor compreensão da exposição individual em áreas urbanas, proporcionando novas perspetivas sobre a exposição individual, essenciais na seleção de estratégias de redução da exposição à poluição atmosférica urbana, e consequentes efeitos na saúde.

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Situado entre o discurso investigativo e o profissional da Didática de Línguas, o presente estudo assenta: num entendimento da educação em línguas como um processo valorizador da diversidade linguística e cultural, tendo como fim último a promoção da intercompreensão e do diálogo intercultural, dentro dos pressupostos de uma didática das línguas e do plurilinguismo; na conceção do professor de línguas como um dos principais atores na educação de cidadãos / comunicadores interculturais, vendo-se, portanto, a braços com novas exigências, para as quais, muitas vezes, não se sente preparado; e nos pressupostos de que a identidade profissional condiciona fortemente a forma como o professor desempenha a sua ação didática, sendo este processo de se tornar professor contínuo e dependente, quer do sujeito-professor e dos seus percursos profissionais e formativos, quer do contexto (profissional, local, nacional, global) em que este se insere. Pretende-se, com este estudo, contribuir para que a educação intercultural seja uma realidade nas nossas escolas, potenciando a sua migração contextualizada dos documentos orientadores das políticas linguísticas e educativas nacionais e transnacionais e dos discursos da investigação em Didática de Línguas. Para o efeito, desenvolvemos um programa de investigação/formação denominado O Professor Intercultural, durante o ano letivo 2006/2007, com professores de línguas (materna e estrangeiras) de três escolas básicas e secundárias do distrito de Aveiro. Este programa integrava um curso (25 horas) e uma oficina (50 horas), ambas as ações de formação acreditadas pelo Conselho Científico-Pedagógico da Formação Contínua. Do ponto de vista formativo, com este programa pretendíamos levar as professoras em formação a desenvolver competências pessoais e profissionais que lhes permitissem gerir a diversidade nos seus contextos profissionais, tendo em vista o desenvolvimento nos seus alunos de uma competência de comunicação intercultural (CCI). Do ponto de vista investigativo, não só pretendíamos compreender as representações dos sujeitos relativamente à educação intercultural em geral e à CCI em particular; como também identificar princípios e estratégias de formação potenciadores do desenvolvimento de competências profissionais docentes para trabalhar a CCI, a partir das perspetivas dos próprios sujeitos. Trata-se, portanto, de um estudo de caso de cariz qualitativo e interpretativo / fenomenológico, com potencialidades heurísticas, que pretende evidenciar os sujeitos, as suas representações, as interações consigo e com os outros e a forma como conceptualizam a identidade profissional docente e as suas dinâmicas de desenvolvimento. Como instrumentos de recolha de dados, privilegiámos os Portefólios Profissionais que foram sendo construídos ao longo do percurso de formação; a sessão “Entre Línguas e Culturas” da plataforma Galanet (www.galanet.eu), recurso de formação no âmbito da oficina (entre fevereiro e maio de 2007); o “Diário do Investigador”; e as “entrevistas narrativas e de confrontação” efetuadas sensivelmente um ano após o final do programa de investigação/formação. Os resultados da análise de conteúdo revelam que os sujeitos consideram a CCI uma competência multidimensional e complexa, reconhecendo três componentes: afetiva (domínio do saber ser e saber viver com o outro), cognitiva (domínio do saber) e praxeológica (domínio do saber-fazer). A componente afetiva constitui, de acordo com os resultados, o motor de arranque do desenvolvimento desta competência, que, posteriormente, é alargada em dinâmicas de informação-(inter)ação-reflexão. Por outro lado, dada a grande pertinência que atribuem à abordagem intercultural e à urgência com que veem a sua integração escolar, os sujeitos consideram a CCI uma das competências inerentes à competência profissional docente, elemento integrador da identidade profissional, numa forte ligação com a missão ética e política que cada vez mais é associada ao docente (de línguas). Para além disso, percecionam o seu desenvolvimento profissional docente como um processo que os acompanha ao longo da vida, fruto das idiossincrasias e predisposições do próprio indivíduo, mas também das dinâmicas da sua formação, das caraterísticas dos contextos em que se movimenta e da colaboração com o Outro, no seu espaço profissional ou fora dele. Importa salientar que este desenvolvimento profissional é potenciado, segundo os nossos resultados, por propostas de formação assentes numa abordagem acional e reflexiva, articulando dinâmicas investigação-ação-reflexão como as propostas no nosso programa de formação, nomeadamente no âmbito da oficina. Neste quadro, concluímos o presente estudo, indicando alguns caminhos possíveis para a formação de professores de línguas para a educação intercultural.

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Chapter 1 introduces the scope of the work by identifying the clinically relevant prenatal disorders and presently available diagnostic methods. The methodology followed in this work is presented, along with a brief account of the principles of the analytical and statistical tools employed. A thorough description of the state of the art of metabolomics in prenatal research concludes the chapter, highlighting the merit of this novel strategy to identify robust disease biomarkers. The scarce use of maternal and newborn urine in previous reports enlightens the relevance of this work. Chapter 2 presents a description of all the experimental details involved in the work performed, comprising sampling, sample collection and preparation issues, data acquisition protocols and data analysis procedures. The proton Nuclear Magnetic Resonance (NMR) characterization of maternal urine composition in healthy pregnancies is presented in Chapter 3. The urinary metabolic profile characteristic of each pregnancy trimester was defined and a 21-metabolite signature found descriptive of the metabolic adaptations occurring throughout pregnancy. 8 metabolites were found, for the first time to our knowledge, to vary in connection to pregnancy, while known metabolic effects were confirmed. This chapter includes a study of the effects of non-fasting (used in this work) as a possible confounder. Chapter 4 describes the metabolomic study of 2nd trimester maternal urine for the diagnosis of fetal disorders and prediction of later-developing complications. This was achieved by applying a novel variable selection method developed in the context of this work. It was found that fetal malformations (FM) (and, specifically those of the central nervous system, CNS) and chromosomal disorders (CD) (and, specifically, trisomy 21, T21) are accompanied by changes in energy, amino acids, lipids and nucleotides metabolic pathways, with CD causing a further deregulation in sugars metabolism, urea cycle and/or creatinine biosynthesis. Multivariate analysis models´ validation revealed classification rates (CR) of 84% for FM (87%, CNS) and 85% for CD (94%, T21). For later-diagnosed preterm delivery (PTD), preeclampsia (PE) and intrauterine growth restriction (IUGR), it is found that urinary NMR profiles have early predictive value, with CRs ranging from 84% for PTD (11-20 gestational weeks, g.w., prior to diagnosis), 94% for PE (18-24 g.w. pre-diagnosis) and 94% for IUGR (2-22 g.w. pre-diagnosis). This chapter includes results obtained for an ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) study of pre-PTD samples and correlation with NMR data. One possible marker was detected, although its identification was not possible. Chapter 5 relates to the NMR metabolomic study of gestational diabetes mellitus (GDM), establishing a potentially predictive urinary metabolic profile for GDM, 2-21 g.w. prior to diagnosis (CR 83%). Furthermore, the NMR spectrum was shown to carry information on individual phenotypes, able to predict future insulin treatment requirement (CR 94%). Chapter 6 describes results that demonstrate the impact of delivery mode (CR 88%) and gender (CR 76%) on newborn urinary profile. It was also found that newborn prematurity, respiratory depression, large for gestational age growth and malformations induce relevant metabolic perturbations (CR 82-92%), as well as maternal conditions, namely GDM (CR 82%) and maternal psychiatric disorders (CR 91%). Finally, the main conclusions of this thesis are presented in Chapter 7, highlighting the value of maternal or newborn urine metabolomics for pregnancy monitoring and disease prediction, towards the development of new early and non-invasive diagnostic methods.

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Considerando que, na sociedade atual, o conhecimento flui incessantemente, renovando-se a cada momento, o cidadão do séc. XXI confronta-se com novos desafios que exigem o desenvolvimento de novas competências. Os recursos da web social – como os fóruns de discussão online –, gratuitos e fáceis de utilizar, permitem que os indivíduos acedam à informação, construam conhecimento, partilhem interesses e desenvolvam múltiplas competências em colaboração. Face a esta realidade, as instituições de Ensino Superior têm vindo a reconhecer que os estudantes já não se sentem confortáveis com abordagens de ensino tradicionais, em que impera a transmissão de informação, preferindo envolver-se em experiências de aprendizagem em que possam interagir com a tecnologia, pelas potencialidades que já lhe reconhecem. Procurando ir ao encontro das exigências da sociedade e do mundo do trabalho atuais, o Processo de Bolonha veio renovar os cursos de Ensino Superior, centrando-os no estudante e no desenvolvimento da autonomia e da colaboração, entre outras competências. Esta tendência vai ao encontro da reconhecida valorização da colaboração com vista à melhoria do desempenho de um grupo profissional. Também no contexto educacional se reconhece o seu contributo para o desenvolvimento profissional do professor e a operacionalização de um ensino por competências. Compete à formação de professores lançar as bases deste movimento.A formação inicial de professores do 1º Ciclo do Ensino Básico tem, entre outras preocupações, a de levar o futuro professor a refletir sobre princípios didáticos que informem a conceção, implementação e avaliação de estratégias e atividades que contribuam para o desenvolvimento de competências nos alunos. Entre as competências a desenvolver nas crianças a frequentar este nível de escolaridade, no que concerne à aprendizagem da língua materna, figura a competência ortográfica, indispensável a uma boa comunicação escrita. Quanto mais cedo for automatizada, mais possibilidades o aluno terá de se ocupar prioritariamente de outros aspetos mais complexos e exigentes do processo de escrita. Tendo em vista estas preocupações, desenvolvemos um estudo, com futuros professores do 1º Ciclo do Ensino Básico a frequentar um mestrado profissionalizante da Universidade de Aveiro, cujos objetivos de investigação eram os seguintes: i) descrever as suas representações sobre colaboração; ii) compreender a influência dessas representações na adoção de práticas colaborativas num fórum de discussão online; iii) compreender o contributo da colaboração adotada num fórum de discussão online para a construção de conhecimento didático sobre a abordagem da ortografia; iv) compreender o contributo desse conhecimento para a conceção de instrumentos didáticos sobre a abordagem da ortografia. Numa primeira fase, o estudo desenvolveu-se com dois grupos de alunos, que nele participaram em dois anos letivos distintos (2009/2010 e 2010/2011), no contexto da unidade curricular de Didática da Língua Portuguesa (inserida no plano de estudos do 1º semestre do 1º ano do Mestrado em Educação Pré- Escolar e Ensino no 1º Ciclo do Ensino Básico da Universidade de Aveiro). Numa segunda fase (entre o 2º semestre do ano letivo de 2011/2012 e 1º semestre do ano letivo de 2012/2013), recolheu-se o resultado de uma intervenção didática desenvolvida por uma professora estagiária (participante na primeira fase do estudo), no âmbito da Prática Pedagógica Supervisionada, apoiada pelo Seminário de Investigação Educacional. Tratando-se de um estudo de caso, a investigação envolveu a recolha de dados através de inquérito por questionário disponibilizado online, uma reflexão individual apresentada por escrito, posts e documentos publicados num fórum de discussão online e instrumentos didáticos (planificação de aulas e relatório de estágio) elaborados pelos estudantes. Procedeu-se a uma análise de conteúdo fundamentada nos quadros teóricos e no estudo empírico.Os resultados vêm aprofundar a discussão em torno da utilização de ferramentas da web social no Ensino Superior, nomeadamente na formação inicial de professores, para desenvolver a colaboração, visando a construção de conhecimento didático, particularmente sobre a abordagem da ortografia. Por um lado, apontam para a influência de representações sobre colaboração na adoção dessa modalidade de trabalho num fórum de discussão online. Por outro, revelam a influência dessa modalidade no conhecimento didático coconstruído e apontam para uma valorização do mesmo por parte dos participantes no estudo, no momento de conceber, implementar e avaliar instrumentos didáticos. Daqui emergiram algumas sugestões pedagógico-didáticas com vista à promoção de práticas inovadoras no Ensino Superior, com recurso a ferramentas da web social, centradas na aprendizagem dos estudantes e no desenvolvimento da colaboração, particularmente na formação inicial de professores.

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With the aim to provide new insights into operational cetacean-fishery interactions in Atlantic waters, this thesis assesses interactions of cetaceans with Spanish and Portuguese fishing vessels operating in Iberian and South West Atlantic waters. Different opportunistic research methodologies were applied, including an interview survey with fishers (mainly skippers) and onboard observations by fisheries observers and skippers, to describe different types of interactions and to identify potential hotspots for cetacean-fishery interactions and the cetacean species most involved, and to quantify the extent and the consequences of these interactions in terms of benefits and costs for cetaceans and fisheries. In addition, the suitability of different mitigation strategies was evaluated and discussed. The results of this work indicate that cetaceans interact frequently with Spanish and Portuguese fishing vessels, sometimes in a beneficial way (e.g. cetaceans indicate fish schools in purse seine fisheries), but mostly with negative consequences (depredation on catch, gear damage and cetacean bycatch). Significant economic loss and high bycatch rates are, however, only reported for certain fisheries and associated with particular cetacean species. In Galician fisheries, substantial economic loss was reported as a result of bottlenose dolphins damaging artisanal coastal gillnets, while high catch loss may arise from common dolphins scattering fish in purse seine fisheries. High cetacean bycatch mortality arises in trawl fisheries, mainly of common dolphin and particularly during trawling in water depths below 350 m, and in coastal set gillnet fisheries (mainly common and bottlenose dolphins). In large-scale bottom-set longline fisheries in South West Atlantic waters, sperm whales may significantly reduce catch rates through depredation on catch. The high diversity of cetacean-fishery interactions observed in the study area indicates that case-specific management strategies are needed to reduce negative impacts on fisheries and cetaceans. Acoustic deterrent devices (pingers) may be used to prevent small cetaceans from approaching and getting entangled in purse seines and set gillnets, although possible problems include cetacean habituation to the pinger sounds, as well as negative side effects on non-target cetaceans (habitat exclusion) and fisheries target species (reduced catch rates). For sardine and horse mackerel, target species of Iberian Atlantic fisheries, no aversive reaction to pinger sounds was detected during tank experiments conducted in the scope of this thesis. Bycatch in trawls may be reduced by the implementation of time/area restrictions of fishing activity. In addition, the avoidance of fishing areas with high cetacean abundance combined with the minimization of fishery-specific sound cues that possibly attract cetaceans, may also help to decrease interactions. In large-scale bottom-set longline fisheries, cetacean depredation on catch may be reduced by covering hooked fish with net sleeves ("umbrellas") provided that catch rates are not negatively affected by this gear modification. Trap fishing, as an alternative fishing method to bottom-set gillnetting and longlining, also has the potential to reduce cetacean bycatch and depredation, given that fish catch rates are similar to the rates obtained by bottom-set gillnets and longlines, whereas cetacean by-catch is unlikely. Economic incentives, such as the eco-certification of dolphin-safe fishing methods, should be promoted in order to create an additional source of income for fishers negatively affected by interactions with cetaceans, which, in turn, may also increase fishers’ willingness to accept and adopt mitigation measures. Although the opportunistic sampling methods applied in this work have certain restrictions concerning their reliability and precision, the results are consistent with previous studies in the same area. Moreover, they allow for the active participation of fishers that can provide important complementary ecological and technical knowledge required for cetacean management and conservation.

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This thesis aims at improving the knowledge on the post-fire vegetation regeneration. For that, forests and shrublands were studied, after forest fires and experimental fires. Maritime Pine (Pinus pinaster) recruitment after fire was studied. Fire severity was evidenced as a major effect on this process. High crown fire severity can combust the pines, destroying the seed bank and impeding post fire pine recruitment. However, crown combustion also influences the post-fire conditions on the soil surface, since high crown combustion (HCC) will decrease the postfire needle cast. After low crown combustion (LCC) (scorched rather than torched crowns), a considerable needle cover was observed, along with a higher density of pine seedlings. The overall trends of post-fire recruitment among LCC and HCC areas could be significantly attributed to cover by needles, as well by the estimation of fire severity using the diameters of the burned twigs (TSI). Fire increased the germination from the soil seed bank of a Pinus pinaster forest, and the effects were also related with fire severity. The densities of seedlings of the dominant taxa (genus Erica and Calluna vulgaris) were contrastingly affected in relation to the unburned situation, depending on fire severity, as estimated from the degree of fire-induced crown damage (LCC/HCC), as well as using a severity index based on the diameters of remaining twigs (TSI). Low severity patches had an increase in germination density relatively to the control, while high severity patches suffered a reduction. After an experimental fire in a heathland dominated by Pterospartum tridentatum, Erica australis and E. umbellata, no net differences in seedling emergence were observed, in relation to the pre-fire situation. However, rather than having no effect, the heterogeneity of temperatures caused by fire promoted caused divergent effects over the burned plot in terms of Erica australis germination – a progressive increased was observed in the plots were maximum temperature recorded ranged from 29 to 42.5ºC and decreased in plots with maximum temperature ranging from 51.5 to 74.5ºC. In this heathland, the seed density of two of the main species (E. australis and E. umbellata) was higher under their canopies, but the same was not true for P. tridentatum. The understory regeneration in pine and eucalypt stands, 5 to 6 years post fire, has been strongly associated with post-fire management practices. The effect of forest type was, comparatively, insignificant. Soil tilling, tree harvesting and shrub clearance, were linked to lower soil cover percentages. However, while all these management operations negatively affected the cover of resprouters, seeders were not affected by soil tilling. A strong influence of biogeographic region was identified, suggesting that more vulnerable regions may suffer higher effects of management, even under comparatively lower management pressure than more productive regions. This emphasizes the need to adequate post-fire management techniques to the target regions.

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The global aim of this thesis was to evaluate and assess the effects of a pesticide (dimethoate) and a metal (nickel), as model chemicals, within different organization levels, starting at the detoxification pathways (enzymatic biomarkers) and energy costs associated (energy content quantification, energy consumption and CEA) along with the physiological alterations at the individual and population level (mortality), leading to a metabolomic analysis (using liquid 1H-NMR) and finally a gene expression analysis (transcriptome and RT-qPCR analysis). To better understand potential variations in response to stressors, abiotic factors were also assessed in terrestrial isopods such as temperature, soil moisture and UV radiation. The evaluation performed using biochemical biomarkers and energy related parameters showed that increases in temperature might negatively affect the organisms by generating oxidative stress. It also showed that this species is acclimated to environments with low soil moisture, and that in high moisture scenarios there was a short gap between the optimal and adverse conditions that led to increased mortality. As for UV-R, doses nowadays present have shown to induce significant negative impact on these organisms. The long-term exposure to dimethoate showed that besides the neurotoxicity resulting from acetylcholinesterase inhibition, this stressor also caused oxidative stress. This effect was observed for both concentrations used (recommended field dose application and a below EC50 value) and that its combination with different temperatures (20ºC and 25ºC) showed different response patterns. It was also observed that dimethoate’s degradation rate in soils was higher in the presence of isopods. In a similar study performed with nickel, oxidative stress was also observed. But, in the case of this stressor exposure, organisms showed a strategy where the energetic costs necessary for detoxification (biomarkers) seemed to be compensated by positive alterations in the energy related parameters. In this work we presented for the first time a metabolomic profile of terrestrial isopods exposed to stressors (dimethoate and niquel), since until the moment only a previous study was performed on a metabolomic evaluation in nonexposed isopods. In the first part of the study we identify 24 new metabolites that had not been described previously. On the second part of the study a metabolomic profile variation of abstract non-exposed organism throughout the exposure was presented and finally the metabolomic profile of organisms exposed to dimethoate and nickel. The exposure to nickel suggested alteration in growth, moult, haemocyanin and glutathione synthesis, energy pathways and in osmoregulation. As for the exposure to dimethoate alterations in osmoregulation, energy pathways, moult and neurotransmission were also suggested. In this work it was also presented the first full body transcriptome of a terrestrial isopod from the species Porcellionides pruinosus, which will complement the scarce information available for this group of organisms. This transcriptome also served as base for a RNA-Seq and a RT-qPCR analysis. The results of the RNA-Seq analysis performed in organisms exposed to nickel showed that this stressor negatively impacted at the genetic and epigenetic levels, in the trafficking, storage and elimination of metals, generates oxidative stress, inducing neurotoxicity and also affecting reproduction. These results were confirmed through RT-qPCR. As for the impact of dimethoate on these organisms it was only accessed through RT-qPCR and showed oxidative stress, an impact in neurotransmission, in epigenetic markers, DNA repair and cell cycle impairment. This study allowed the design of an Adverse Outcome Pathway draft that can be used further on for legislative purposes.

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Environmental contamination and climate changes constitute two of the most serious problems affecting soil ecosystems in agricultural fields. Agriculture is nowadays a highly optimized process that strongly relies on the application of multiple pesticides to reduce losses and increase yield production. Although constituting, per se, a serious problem to soil biota, pesticide mixtures can assume an even higher relevance in a context of unfavourable environmental conditions. Surprisingly, frameworks currently established for environmental risk assessments keep not considering environmental stressors, such as temperature, soil moisture or UV radiation, as factors liable to influence the susceptibility of organisms to pesticides, or pesticide mixtures, which is raising increasing apprehension regarding their adequacy to actually estimate the risks posed by these compounds to the environment. Albeit the higher attention received on the last few years, the influence of environmental stressors on the behaviour and toxicity of chemical mixtures remains still poorly understood. Aiming to contribute for this discussion, the main goal of the present thesis was to evaluate the single and joint effects of natural stressors and pesticides to the terrestrial isopod Porcellionides pruinosus. The first approach consisted on evaluating the effects of several abiotic factors (temperature, soil moisture and UV radiation) on the performance of P. pruinosus using several endpoints: survival, feeding parameters, locomotor activity and avoidance behaviour. Results showed that these stressors might indeed affect P. pruinosus at relevant environmental conditions, thus suggesting the relevance of their consideration in ecotoxicological assays. At next, a multiple biomarker approach was used to have a closer insight into the pathways of damage of UV radiation and a broad spectrum of processes showed to be involved (i.e. oxidative stress, neurotoxicity, energy). Furthermore, UV effects showed to vary with the environment medium and growth-stage. A similar biomarker approach was employed to assess the single and joint effects of the pesticides chlorpyrifos and mancozeb to P. pruinosus. Energy-related biomarkers showed to be the most differentiating parameters since age-classes seemed to respond differently to contamination stress and to have different metabolic costs associated. Finally, the influence of temperature and soil moisture on the toxicity of pesticide mixtures was evaluated using survival and feeding parameters as endpoints. Pesticide-induced mortality was found to be oppositely affected by temperature, either in single or mixture treatments. Whereas chlorpyrifos acute toxicity was raised under higher temperatures the toxicity of mancozeb was more prominent at lower temperatures. By the opposite, soil moisture showed no effects on the pesticide-induced mortality of isopods. Contrary to survival, both temperature and soil moisture showed to interact with pesticides to influence isopods’ feeding parameters. Nonetheless, was however the most common pattern. In brief, findings reported on this thesis demonstrated why the negligence of natural stressors, or multiple stressors in general, is not a good solution for risk assessment frameworks.

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During the last century mean global temperatures have been increasing. According to the predictions, the temperature change is expected to exceed 1.5ºC in this century and the warming is likely to continue. Freshwater ecosystems are among the most sensitive mainly due to changes in the hydrologic cycle and consequently changes in several physico-chemical parameters (e.g. pH, dissolved oxygen). Alterations in environmental parameters of freshwater systems are likely to affect distribution, morphology, physiology and richness of a wide range of species leading to important changes in ecosystem biodiversity and function. Moreover, they can also work as co-stressors in environments where organisms have already to cope with chemical contamination (such as pesticides), increasing the environmental risk due to potential interactions. Therefore, the objective of this work was to evaluate the effects of climate change related environmental parameters on the toxicity of pesticides to zebrafish embryos. The following environmental factors were studied: pH (3.0-12.0), dissolved oxygen level (0-8 mg/L) and UV radiation (0-500 mW/m2). The pesticides studied were the carbamate insecticide carbaryl and the benzimidazole fungicide carbendazim. Stressors were firstly tested separately in order to derive concentration- or intensity-response curves to further study the effects of binary combinations (environmental factors x pesticides) by applying mixture models. Characterization of zebrafish embryos response to environmental stress revealed that pH effects were fully established after 24 h of exposure and survival was only affected at pH values below 5 and above 10. Low oxygen levels also affected embryos development at concentrations below 4 mg/L (delay, heart rate decrease and edema), and at concentrations below 0.5 mg/L the survival was drastically reduced. Continuous exposure to UV radiation showed a strong time-dependent impact on embryos survival leading to 100% of mortality after 72 hours of exposure. The toxicity of pesticides carbaryl and carbendazim was characterized at several levels of biological organization including developmental, biochemical and behavioural allowing a mechanistic understanding of the effects and highlighting the usefulness of behavioural responses (locomotion) as a sensitive endpoint in ecotoxicology. Once the individual concentration response relationship of each stressor was established, a combined toxicity study was conducted to evaluate the effects of pH on the toxicity of carbaryl. We have shown that pH can modify the toxicity of the pesticide carbaryl. The conceptual model concentration addition allowed a precise prediction of the toxicity of the jointeffects of acid pH and carbaryl. Nevertheless, for alkaline condition both concepts failed in predicting the effects. Deviations to the model were however easy to explain as high pH values favour the hydrolysis of carbaryl with the consequent formation of the more toxic degradation product 1- naphtol. Although in the present study such explanatory process was easy to establish, for many other combinations the “interactive” nature is not so evident. In the context of the climate change few scenarios predict such increase in the pH of aquatic systems, however this was a first approach focused in the lethal effects only. In a second tier assessment effects at sublethal level would be sought and it is expectable that more subtle pH changes (more realistic in terms of climate changes scenarios) may have an effect at physiological and biochemical levels with possible long term consequences for the population fitness.

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Com esta investigação pretendemos analisar as perspectivas e opiniões dos professores de Portugugs, relativamente A questáo da Gestão Curricular da Língua Cabo-vediana e sua integração nos curficula. O trabalho divide-se em duas partes, sendo a primeira parte abrangendo a coniextualizaç~od o problema e objecto de estudo, e o enquadramento tebrico, com base nos suportes te6ricos de referência e a segunda parte abarca a enquadramento metodológico de um estudo prospectivo, concretizado através da realização de um inquérito por questionário aplicado a uma amostra dos professores de Português de Cabo Verde. Na primeira parte do trabalho, para além do conceito de curriculo. que foi largamente descrito a nível teórico, o estudo centra-se no conceito de gesfão cvrricular da Ccv e as suas inter-relaçáes com os conceitos de adequaçio, diferenciação e integra@ curricuiares, a luz das novas tendemias curriculares e de inovação educativa. Um outro ponto que tem merecido destaque, nesta primeira parte diz respeito aos conceitos de crioulo e pidgin e a formação do Ccv e a sua conversão em Ccv. Assim, atribuímos A política linguística ai legiiimaçào da criação de estruturas e meios indispensáveis para a afirmação e valorizaç8a da Lcv e sua integração nos curricula. A concepção da nossa investigação situa-se dentro do paradigma construtívista, conforme definido por Guba & Lincoln (19941, que permite a compreensão da realidade sob a forma de construções mentais e sociais, baseadas na interpretação e analise de conteúdo de dados obtidos junto dos sujeitos, Para a abordagem metodológica utilizada nesta pesquisa utilizou-se o inquérito por question8rio1 com recurso ao método quantitativdqualitativo, visto que se trata de um estudo descritivolinterpretativo de natureza exploratória, que se preocupa mais com o processo do que com os prdutos. A síntese dos resultados demonstra que os professores têm a noção dos conceitos de currículo e de gestão curricular, embora haja algumas divergências na conceptualização dos mesmos. No tocante à Lcv, é clara a ansiedade que os professores deixam transparecer de ver a sua Ilngua materna valorizada, no sentido da sua ascensão A língua oficial em paridade com a Lp. Assim, advoga-se a criação de estruturas e de gestão de meios materiais a humanos para a oficialiração da Lcv e sua integração nos çurricula escolares.

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According to the World Health Organization, around 8.2 million people die each year with cancer. Most patients do not perform routine diagnoses and the symptoms, in most situations, occur when the patient is already at an advanced stage of the disease, consequently resulting in a high cancer mortality. Currently, prostate cancer is the second leading cause of death among males worldwide. In Portugal, this is the most diagnosed type of cancer and the third that causes more deaths. Taking into account that there is no cure for advanced stages of prostate cancer, the main strategy comprises an early diagnosis to increase the successful rate of the treatment. The prostate specific antigen (PSA) is an important biomarker of prostate cancer that can be detected in biological fluids, including blood, urine and semen. However, the commercial kits available are addressed for blood samples and the commonly used analytical methods for their detection and quantification requires specialized staff, specific equipment and extensive sample processing, resulting in an expensive process. Thus, the aim of this MSc thesis consisted on the development of a simple, efficient and less expensive method for the extraction and concentration of PSA from urine samples using aqueous biphasic systems (ABS) composed of ionic liquids. Initially, the phase diagrams of a set of aqueous biphasic systems composed of an organic salt and ionic liquids were determined. Then, their ability to extract PSA was ascertained. The obtained results reveal that in the tested systems the prostate specific antigen is completely extracted to the ionic-liquid-rich phase in a single step. Subsequently, the applicability of the investigated ABS for the concentration of PSA was addressed, either from aqueous solutions or urine samples. The low concentration of this biomarker in urine (clinically significant below 150 ng/mL) usually hinders its detection by conventional analytical techniques. The obtained results showed that it is possible to extract and concentrate PSA, up to 250 times in a single-step, so that it can be identified and quantified using less expensive techniques.

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According to the World Health Organization, around 8.2 million people die each year with cancer. Most patients do not perform routine diagnoses and the symptoms, in most situations, occur when the patient is already at an advanced stage of the disease, consequently resulting in a high cancer mortality. Currently, prostate cancer is the second leading cause of death among males worldwide. In Portugal, this is the most diagnosed type of cancer and the third that causes more deaths. Taking into account that there is no cure for advanced stages of prostate cancer, the main strategy comprises an early diagnosis to increase the successful rate of the treatment. The prostate specific antigen (PSA) is an important biomarker of prostate cancer that can be detected in biological fluids, including blood, urine and semen. However, the commercial kits available are addressed for blood samples and the commonly used analytical methods for their detection and quantification requires specialized staff, specific equipment and extensive sample processing, resulting in an expensive process. Thus, the aim of this MSc thesis consisted on the development of a simple, efficient and less expensive method for the extraction and concentration of PSA from urine samples using aqueous biphasic systems (ABS) composed of ionic liquids. Initially, the phase diagrams of a set of aqueous biphasic systems composed of an organic salt and ionic liquids were determined. Then, their ability to extract PSA was ascertained. The obtained results reveal that in the tested systems the prostate specific antigen is completely extracted to the ionic-liquid-rich phase in a single step. Subsequently, the applicability of the investigated ABS for the concentration of PSA was addressed, either from aqueous solutions or urine samples. The low concentration of this biomarker in urine (clinically significant below 150 ng/mL) usually hinders its detection by conventional analytical techniques. The obtained results showed that it is possible to extract and concentrate PSA, up to 250 times in a single-step, so that it can be identified and quantified using less expensive techniques.

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O cancro do cólon e reto (CCR) representa uma das neoplasias malignas mais relevantes, não só pela morbilidade mas também pelas altas taxas de mortalidade. Paralelamente, esta neoplasia representa uma elevada sobrecarga psicossocial, para o indivíduo, que se reflete na existência de sintomatologia depressiva e ansiosa e de uma qualidade de vida deficitária e que se estima influenciar o processo de adesão terapêutica. Assim, o presente estudo tem como objetivo estudar a associação das variáveis sóciodemográficas, clínicas e de ajustamento psicossocial, com a adesão terapêutica em doentes com cancro colo-rectal. Trinta e cinco pacientes com cancro colo-rectal, acompanhados na Liga Portuguesa Contra o Cancro, foram selecionados de acordo com o método de amostragem de conveniência. Os instrumentos de avaliação psicossocial utilizados consistiram nos seguintes: questionário de variáveis sociodemográficas e clínicas; na Escala de Ansiedade e Depressão Hospitalar (EADH); no questionário de Qualidade de Vida da Organização Europeia de Investigação e Tratamento de Cancro (QLQC30) e na Escala de Adesão Geral (EAG). Os resultados obtidos revelam a existência de relações significativas entre sintomatologia psicopatológica, qualidade de vida e adesão ao tratamento em pacientes com CCR, mais espeficamente, encontrou-se que: a sintomatologia psicopatológica correlacionou-se negativamente com adesão ao tratamento e com a qualidade de vida, e a adesão ao tratamento associou-se positivamente com a qualidade de vida. Concluimos que o presente estudo contribui com a clarificação do sofrimento psicossocial do paciente com CCR e da interação das variáveis demográficas, clínicas e de ajustamento psicossocial com a adesão terapeutica destes doentes. Implicações clinicas e de investigação são apontadas neste contexto.

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Curso superior de traducción, concebido fundamentalmente como una actividad práctica, en la que la automotivación es esencial a fin de que el alumno adquiera las habilidades necesarias para transmitir de manera integral el sentido de un texto en lengua extranjera (francés) a su lengua materna (español).

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Dissertação de Mestrado, Aquacultura e Pescas, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2009