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- Study of the prevalence and clinical features of food allergies in adults and adolescents from Beira InteriorPublication . Lozoya Ibáñez, Carlos; Barata, Luís Manuel TabordaBackground: Food allergy is an important health problem in western-style countries, and its prevalence has increased in the last three decades. Studies of the prevalence of food allergy in the general population in Portugal are scarce. Thus, the objectives of the present thesis were: a) to design and validate a food allergy study questionnaire for Portuguese adults, b) to determine the prevalence, and clinical characteristics of food allergy in a population of adolescents and adults in Beira Interior, and c) to determine the prevalence, and clinical characteristics of food allergy in the elderly population worldwide by conducting a systematic review of the bibliography and a subsequent meta-analysis of the data. Methods: A 17-item questionnaire was developed and applied by phone to a group of food allergy patients and a group of healthy individuals, with subsequent reassessment (re-test). Face and content validity, intelligibility, construct validity, and test-retest reliability (temporal stability) were analysed. This tool, once validated, was applied in two population-based individuals samples (3,168 adolescents; mean age: 14.3±1.1; 51.7% female; 1.436 adults; mean age of 47 years, median age: 45 years, 50.6% female), registered at participating Healthcare cross-sectional studies performed in various healthcare centres and secondary schools from central Portugal. All randomly selected individuals (1702 adolescents; mean age: 14.9±2.1 years; median age: 14 years; 61.9% female; 840 adults; (mean age: 48 years, median age: 46 years, 51.3% female) replied to the food allergy questionnaire by phone (adults) or in a written form (adolescents). Those who reported an adverse food reaction were invited to come to the hospital, where clinical history was taken, skin prick (SPT) and prick-prick skin (SPPT) tests were performed and food allergen-specific IgE levels (sIgE) were determined. An open oral challenge was performed in selected cases. Cases of positive clinical history of immediate (up to 2 hours after ingestion) reaction in association with positive food sIgE levels and/or skin prick tests were classified as IgE-associated probable food allergy. Cases of positive clinical history of delayed (more than 2 hours after ingestion) and negative food sIgE levels independently of positive SPT or SPPT results were classified as non-IgE associated probable food allergy. A systematic review and meta-analysis on the prevalence and risk factors for food allergy in elderly individuals were conducted. A searched of international electronic databases including MEDLINE, EMBASE, Cochrane Library, CINAHL, AMED and ISI Web of Science, as well as clinical trials databases for published, unpublished and on-going studies from 1980 to 2019. There were no restrictions on the language or geography of publication. The Critical Appraisal Skills Programme (CASP) quality assessment tool was used to appraise the methodological quality of the included studies. A descriptive summary with data tables was elaborated, and when clinically relevant and statistically adequate, a meta-analysis using random-effects modelling was carried out, given the expected clinical, methodological and statistical heterogeneity of the selected studies. The PRISMA checklist guided the reporting of the systematic review. Results: Face and content validity of the questionnaire allowed item reduction from 30 to 17 items with adequate content validity index > 0.78. Construct validity was confirmed in a group of 66 confirmed food allergic patients. Test-Retest Reliability (general temporal stability) of the test had a Spearman correlation coefficient value of 0.845 for the retest. Cohen's Kappa values for the relevant questions were greater than 0.890 for almost all items. No differences were found when sex, age and volunteers’ recruitment origin were analysed. An inverse relationship was found between reliability and retest time interval. The prevalence of probable food allergy in our sample was 1.41% in adolescents and 1% in adults, with fresh fruits and shellfish in adolescents and shellfish and fish in adults as the most frequently implicated foods. IgE-mediated probable food allergy occurred in 1.23% of adolescent and in 0.71% of adult cases, and fresh fruits and shellfish in adolescents and shellfish and peanut in adults were the foodstuffs mainly involved. Cutaneous symptoms were most frequently reported and prevalence values and food types were discrepant between self-reported and probable food allergies in both populations. The prevalence of food allergy in the elderly was 6.46% for self-report, slightly lower than that of SR + food-specific IgE levels (6.95%) and SR + SPT (1.30%). In addition, it was lower than that in non-elderly adults, but higher than in children assessed by self-report outcomes. Finally, it was lower when compared with the other age groups when self-report symptoms were combined with in vitro or in vivo outcome assessment. No results were obtained regarding time and geographical trends, predominant foods, risk and prognostic factors, and clinical manifestations of food allergy in the elderly. There was great heterogeneity both in the systematic review and the meta-analysis, which was lowest for shellfish (I2=0.000%) and highest for fruits (I2=98.205%). Conclusions: Due to the quick and easy implementation, confirmation of face, content and construct validity as well as high temporal reproducibility, the screening questionnaire was a useful study tool for an initial approach to detection of food allergies in adults. The prevalence of probable food allergies in Portuguese adolescents and adults was low, mostly related to fresh fruits, shellfish, nuts and peanut in the former, and to shellfish, fish, peanut and nuts in the latter. Most cases frequently involved cutaneous symptoms. The systematic review allowed us to draw up-to-date estimates of the prevalence of adverse food reactions in elderly individuals, worldwide. However, most of the studies were not focused on the population over 60 years of age, which resulted in an evident lack of information and biases that might affect exposure and outcomes. This fact conditioned the knowledge of the clinical characteristics, implicated foods, evolution and diagnosis of food allergy in these individuals, as well as the development of possible preventative measures focused specifically on the elderly population.
- Intervenção no Bairro do BarrunchoPublication . Gonzaga, Jorge Daniel; Pedrosa, Patrícia Alexandra Dias SantosA presente investigação teórico-prática, tem como objeto de estudo a intervenção no Bairro do Barruncho localizado em Odivelas, inserido no PER e na ACRRU, questionando o espaço público e o que este acarreta na relação com os usuários e levantando a questão da viabilidade quanto aos métodos de intervenção urbana em territórios autoproduzidos. Os objetivos definidos para o projeto visaram dar respostas e soluções para o fenómeno dos assentamentos clandestinos, tendo em consideração a grande complexidade urbana, a sua origem, as consequências socias, culturais, econômicas e étnicas do Bairro, relevando a importância que o espaço público tem enquanto elemento gerador e organizador da relação humana. Através da análise espacial e temporal, observa-se que durante décadas existiu uma lenta resposta para o tratamento da problemática da construção clandestina, onde as respostas institucionais e os instrumentos de planeamento e gestão do território tardam, e exigem uma extensa burocracia e logística. A presente situação do Bairro do Barruncho, apresenta problemas e desarticulações na maioria das relações que estabelece com a envolvente e nas relações internas ao bairro, isto conduz à urgência de encontrar soluções de reabilitação. Desta forma, conclui-se que o Espaço Público é um dos elementos mais afetados neste contexto, sendo que este é fundamental ao bem-estar de uma comunidade, considerando-se pertinente refletir o sistema de intervenção em áreas urbanas de génese ilegal, assim apresenta-se o espaço público como elemento estratégico na reabilitação e requalificação, sendo possível demonstrar a importância de pensar as intervenções no espaço coletivo como uma estratégia da reabilitação de áreas urbanas clandestinas, em articulação com a promoção da boa forma urbana e paisagista, em prol da diminuição dos problemas sociais, económicos e urbanos, contribuindo positivamente para uma cidade mais justa.
- Revitalização Social através da Requalificação UrbanaPublication . Gaspar, João José Augusto Quelhas; Virtudes, Ana Lídia Moreira Machado Santos das; Baptista, Luís Vítor Silva Dias AlçadaHá décadas que, de um modo geral e de forma crescente, tem vindo a registar-se o abandono de zonas urbanas de baixa densidade, no Interior de Portugal, com o decréscimo acentuado da população residente e o seu envelhecimento. Este facto tem vindo a ter consequências quase irreversíveis para esses lugares e para quem neles continua a habitar de forma quase heroica. Tais transformações manifestam-se na perda de equipamentos de cariz social e consequentemente, na desqualificação da malha urbana. Também as alterações no paradigma social e familiar tradicional, com o envelhecimento dos que ai´ permanecem não é alheio a este facto. Assim, são necessárias políticas e estratégias para a revitalização social destes lugares, promotoras da fixação da população e das atividades económicas, como é o caso da União de Freguesias de Cantar-Galo e Vila do Carvalho nos subúrbios da cidade da Covilhã. Como se analisa nesta dissertação, tais estratégias poderão passar, entre outras medidas, pela requalificação urbanística, como mote para a revitalização social. Tornar estes lugares mais qualificados, quer ao nível da habitação, quer dos espaços coletivos, atribuindo-lhes novas valências, contribuirá para promover um maior nível de serviços “essenciais” aos desafios e exigências da vida contemporânea. Entre outras considerações, concluiu-se que Cantar-Galo e Vila do Carvalho registam populações envelhecidas da ordem dos 13% a 17%, respetivamente. Os tecidos urbanos incluem grande diversidade de equipamentos e instituições sociais que, contudo, estão de um modo geral, degradadas, desaproveitadas ou com funções obsoletas face às necessidades atuais. Os 4102 edifícios habitáveis (Censos 2011) correspondem a uma média de 3 fogos por família na Vila do Carvalho e de 2 fogos por família em Cantar-Galo. Apenas 4,2% estão em ruínas, pelo que não têm uma repercussão negativa na imagem urbana. Contudo, aspetos como a falta ou desadequação dos passeios, frequentemente em ruas centrais, com larguras inferiores a 1 metro (como na Rua 30 de junho) prejudicam a vivência do local e a mobilidade dos cidadãos, requerendo destaque prioritário em futuras intervenções urbanísticas.
- Mercúrio em Cogumelos Selvagens Níveis e Riscos para HumanosPublication . Santos, Mariana Flor Neves dos; Pastorinho, Manuel Ramiro Dias; Sousa, Ana Catarina Almeida; Barata, Luís Manuel TabordaOs cogumelos selvagens são muito apreciados e procurados em várias regiões do mundo e fazem parte da alimentação humana desde há milhares de anos. Tem sido relatado por muitos estudos que os cogumelos têm o potencial de bioacumulação de metais, como o mercúrio. Isso levanta algumas questões e preocupações. Será que este potencial de bioacumulação será verificado nas espécies apanhadas na Cova da Beira? Será que os níveis de mercúrio detetados estarão acima da dose de referência? Uma vez que a Cova da Beira é afetada por incêndios florestais quase todos os verões, espera-se que as amostras de cogumelos recolhidas exibam mercúrio, uma vez que os incêndios provocam a remobilização do mercúrio. O principal objetivo deste estudo é descrever os níveis de mercúrio em algumas espécies de cogumelos encontradas na Cova da Beira, verificar o seu potencial de bioacumulação de metais e, finalmente, averiguar existência ou não de riscos para o homem, associados ao consumo destas espécies. Além disso, pretende-se elaborar uma lista de recomendações para aumentar a consciencialização dos níveis de contaminação de cada local e tentar diminuir o consumo de mercúrio através da diminuição ou até abstenção do consumo das espécies que estiverem mais contaminadas. A ordem de grandeza dos níveis de mercúrio obtidos para as diferentes espécies amostradas foi Tricholoma equestre>Lactarius deliciosus>Tricholoma portentosum>Russula vesca. As amostras recolhidas no Alcaide apresentaram os níveis de mercúrio mais elevados. Em contrapartida, Terlamonte apresentou os níveis mais baixos. O solo e vegetação recolhidos em associação com as amostras de cogumelos, apresentaram concentrações inferiores às dos cogumelos correspondentes, indicando que têm um potencial de acumulação inferior à dos cogumelos. As concentrações de mercúrio verificadas no solo (inferiores ao cogumelo correspondente) comprovam a capacidade de biorremediação do solo pelos dos cogumelos.
- Reliability study on avionics: feasibility study to determine mean time between failure (MTBF)Publication . Correia, João Filipe Gonçalves; Saúde, José Manuel Mota Lourenço da; Marques, Nuno Miguel Guerra GentilIn general, the world faces an increase in the pressure to perform faster, better and cheaper, requiring engineers to predict accurately the reliability of products. In the early stages of the design process, these accurate predictions will contribute not only to a more robust and reliable product, but also will drive down the costs associated with redesigning the equipment/component, for example, when a product is already in production and a design error is found or as the result to improve the reliability obtained from operation. The number of electronic components, equipment and systems in an airplane increases with the new developments in technology. That is why it is imperative that manufacturer predict the failure rate and the mean time between failure of each equipment/component with the greatest accuracy. For this accuracy to be fulfilled, there are three methodologies: empirical (based on standards), failure mechanisms, and accelerated/life tests. The most common methodology is the use of standards. The main handbook/standard used in the electronics industry for the prediction of the mean time between failure is the MIL-HDBK-217F. However, at the present moment of technology development, this handbook is obsolete, as the predicted values are far from the reality. To overcome this problem, several companies from aeronautic and aerospace sector developed a standard called FIDES, which incorporate the three methodologies so that there was a significant improvement in predicting the probability of systems failure. By the fact that this standard is updated periodically and revised, it makes it one of the most suitable and accurate methods of predicting the probability of failure and mean time between failure for recent technologies. Therefore, this dissertation is based on this standard, using the methodology described alongside with the information and data retrieved in collaboration with Aeromec, for calculating the mean time between failure of electronic components, four integrated circuits. The final aim of this study is to establish a methodology to predict the mean time between failure of a specific component, giving to Aeromec a relevant process, namely the methodology implemented, to do the calculations for the equipment to be fitted on to an aircraft, and if feasible, then make adjustments to the aircraft maintenance programs under their responsibility The comparison of the results obtained was carried out by comparing it with an estimated value for the mean time between failure of the four integrated circuits done by Flight Data Systems with the “ReliaSoft” reliability prediction software. With this study it was found that the prediction of the mean time between failure for the four integrated circuits, carried out using the FIDES standard, is more optimistic and therefore with a longer/higher mean time between failure then the prediction made by Flight Data Systems with the MIL-HDBK-217F standard. This may be due to two factors: the MIL-HDBK-217F standard has not been reviewed and updated for new technologies since 1995, contrary to the FIDES standard; and the usage profile in Flight Data Systems prediction does not exactly match as the one in FIDES. For future works, the next step is to conduct a full study to assess the mean time between failure for a specific equipment, for example a primary flight display that has several different components, meaning estimate the mean time between failure for every component incorporated, and then the overall mean time between failure. This work could be done by Aeromec to assess the mean time between failure for the equipment that will be installed in to aircraft in maintenance.