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Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Information Analysis and Management Since the early stages of the COVID-19 pandemic, governments resorted to non-pharmaceutical interventions (NPI) to contain the spread of the disease. Despite being considered the most effective measures in the absence of specific treatments and vaccines, NPI's raise several concerns as they are closely associated with severe negative social and economic impacts. We evaluate the effect of NPI on reducing COVID-19 mortality and assess if stricter NPI's are associated with fewer fatalities. A multiple linear regression model linking the COVID-19 mortality rate with a set of ten NPI's is estimated for six countries European countries using data from the disease's first wave. From the analysis, no clear and consistent pattern emerges across the six countries regarding the effectiveness of the implemented NPI's. Stay-at-home requirements is the measure most associated with a reduction in the mortality rate. The relationship between higher levels of strictness and a reduction in mortality was also scarce. The identified variation in the effectiveness of NPI provides support for a strategy in which restrictions are implemented with a tailored approach rather than in a standardised way. This study helps inform health authorities and policy makers on the most effective practices in the application of NPI's in either present or future epidemics, with the aim of balancing safety with wellbeing and the overall functioning of society and the economy.

Endoscopic stenting is a well-established option for the treatment of malignant obstruction, temporary management of benign strictures, and sealing transmural defects, as well as drainage of pancreatic fluid collections and biliary obstruction. In recent years, in addition to expansion in indications for endoscopic stenting, considerable strides have been made in stent technology, and several types of devices with advanced designs and materials are continuously being developed. In this review, we discuss the important developments in stent designs and novel indications for endoluminal and transluminal stenting. Our discussion specifically focuses on (i) biodegradable as well as (ii) irradiating and drug-eluting stents for esophageal, gastroduodenal, biliary, and colonic indications, (iii) endoscopic stenting in inflammatory bowel disease, and (iv) lumen-apposing metal stent.

During our life our bones are in a constant balance between bone formation by osteoblasts and bone resorption by osteoclasts. Bone morphogenetic proteins are a group of cytokines from the transforming growth factor-β family involved in several processes. Their signal is transduced through two types of serine/threonine kinase receptors, BMPRI and BMPRII. BMPRIA is a type one receptor involved in osteoblast/osteoclast communication and therefore affecting bone metabolism. Upon binding of different ligands, type II phosphorylates the type I and activates one of the signal pathways. Although their function is known, the mechanisms of regulation of expression are still unclear. The objective of this work was to characterize some of the Mus musculus Bmpr1a molecular regulatory mechanisms including upstream open reading frames (uORFs), polyadenylation sites, microRNA binding sites and constitutive decay elements (CDE). Bioinformatically, we were able to identify 11 Mus musculus Bmpr1a transcripts on available databases, 11 polyadenylations and a constitutive decay element on the 3’UTR, while on 5’UTR we were able to identify 3 uORFs. Experimentally, we isolated a new and shorter Bmpr1a 3’UTR with an alternative polyadenylation site from MC3T3-E1 but without the CDE We tried to isolate different fragments from different tissues, but we were capable of isolate a longer transcript only from mouse liver that contains the CDE loop. Within the 5’UTRs we isolated 4 different fragments containing 2 or 3 uORFs and insert them on reporter plasmids for functional analysis. The last step was mutating all the AUG from uORFs and validating their effect on regulation of luciferase expression. We measured a decrease in the expression of luciferase on fragments containing no mutations and an increase in the expression of fragments with mutations, except in one case where the mutation was inserted 7bp after the start of the fragment. Results indicate that there were no different transcripts from proliferating and differentiated cells, and in the 5’ UTR , the uORFs could possibly contribute to regulate the expression of Bmpr1a. However further studies are needed to confirm and expand our data. As Bone morphogenetic proteins (BMP) são um grupo de citocinas pertencentes à família de proteínas do Transforming growth factor β e estão envolvidas em vários processos celulares importantes como o regulamento da divisão celular e de diferenciação de células. Estas proteínas transmitem o sinal para dentro das células através de dois tipos de recetores de serina/treonina diferentes, os Bone morphogenetic proteins receptors (BMPR) tipo I e tipo II. Estes recetores formam homo e hétero dímeros entre si para formar um recetor totalmente funcional; quando isso acontece e após a ligação de uma molécula aos receptores, o tipo II fosforila o tipo I levando a uma cascata de fosforilação no interior da célula podendo ativar diferentes vias se sinalização dependendo da molécula que se liga ao recetor e qual os dímeros de recetores que se formaram. Alguns dos exemplos de vias de sinalização que se ativam aquando da ligação de moléculas a estes recetores são as vias Smad, MAPK, PI3K/Akt, Wnt ou ERK1/2 que são importantes reguladores da expressão de genes e que atuam em processos celulares importantes como diferenciação celular e formação de tecidos. As BMPRs estão envolvidas também nos processos de metabolismo do osso associados à deposição de hidroxiapatite pelos osteoblastos e reabsorção óssea pelos osteoclastos que degradam a matriz extracelular. Apesar de se conhecer a função da BMPR1A, nem todos os mecanismos de regulação pós-transcrição da sua expressão estão estudados. O objetivo deste trabalho é contribuir para a caracterização dos mecanismos de regulação dos diferentes transcritos de Bmpr1a, e determinar quais os elementos regulatórios pós-transcrição presentes nas sequências identificadas, tanto na região 5’ untraslated region (UTR), como na região 3’UTR. Começou-se por identificar os diferentes transcritos de bmpr1a sendo possível identificar 11 diferentes transcritos de Bmpr1a de mus musculus (ratinho) e 5 diferentes transcritos de BMPR1A de homo sapiens (humano) em diferentes bases de dados. Procurou-se também identificar sequencias associadas a locais de poliadenilação sendo que no ratinho foi possível encontrar 11 diferentes locais de poliadenilação, dos quais 6 contêm a sequencia canónica de poliadenilação, enquanto os outros 5 foram obtidos através do uso de ferramentas bioinformáticas como o RegRNA2.0. Nos transcritos de homo sapiens identificou se 8 locais de poliadenilação. De seguida identificou se a presença de um loop de degradação constitutivo (Constitutive Decay Element - CDE). Este loop está presente em 8 das 11 sequencias de ratinho identificadas enquanto no humano está presente em todos os transcritos. Verificou-se igualmente a conservação deste loop em 24 espécies diferentes e foi possível verificar que se encontra totalmente conservado em 18 dessas 24 espécies e em 22 delas contem a sequencia necessária para que seja funcional. Outro dos elementos regulatórios que se identificou foram locais ricos em Adeninas/Uracilos que são associados a um aumento de afinidade de ligação de proteínas reguladoras. Foi possível identificar a sequencia mínima para a ligação dessas proteínas, mas não foi possível encontrar um dos 5 diferentes conjuntos de sequências que estão descritas na literatura. Por último construiu-se uma árvore filogenética da região 3’UTR dos transcritos de Bmpr1a para perceber as relações filogenéticas desta região não codificante entre diferentes espécies de vertebrados. Na região 5’ identificou-se a presença de upstream Open Reading frames (uORFs) tendo sido verificada a presença de 3 uORFs conservadas na maior parte dos transcritos analisados e conservados em várias espécies de mamíferos exceto nos marsupiais. Experimentalmente, foi possível isolar um transcrito da região 3’UTR de Bmpr1a de ratinho com 250 pares de bases tanto em células em proliferação como em células diferenciadas em osteoblastos. Este transcrito contém um local de poliadenilação alternativo antes da cauda de poliadeninas e não contém o loop de degradação constitutivo. Foi-se então tentar isolar transcritos de outros tecidos de ratinho. Começou se por tentar isolar transcritos de Bmpr1a em tecidos de joelho e de articulações não sendo possível isolar transcritos de outros tamanhos além do transcrito de 250 pares de bases acima indicado. No entanto foi possível identificar a partir de fígado um transcrito com 1500 pares de base o qual já contem o loop de degradação constitutivo. Na região 5’ isolamos 4 fragmentos diferentes contendo 2 ou 3 das uORFs e com diferentes distâncias entre estas e o início dos fragmentos. Esses 4 fragmentos foram de seguida inseridos com a orientação correta num vetor de expressão para a luciferase e transfectados em células Hek293 (do inglês Human Embrionic Kidney) e os valores de luminescência registados. Observou-se nos resultados preliminares uma diminuição da expressão da luciferase associada à presença das uORFs dos transcritos sem mutações. Apos a mutação dos AUGs para AAG por SDM verificou-se que no fragmento mais longo (fragmento A) parece haver uma tendência para o aumento da luciferase ao longo das mutações sequenciais dos AUG, confirmado pelas mutações individuais. No segundo fragmento (fragmento B) analisado ocorre um aumento da expressão da luciferase quando se mutou o AUG da uORF1 em comparação com o controlo, contudo na mutação da uORF2 ocorre uma diminuição dramática da expressão da luciferase que é confirmada pela mutação isolada da uORF. Uma das possíveis explicações para esta diminuição da expressão da luciferase é a localização desta uORF no fragmento, pois esta uORF está localizada no início do fragmento, a 7 pares de base do início da mesma, podendo levar a uma destabilização deste fragmento e consequentemente levando ao resultado observado, ou seja, à diminuição da expressão da luciferase. No último fragmento (fragmento D) que não contem a uORF2 é possível observar uma diminuição da expressão da luciferase no fragmento sem nenhuma mutação dos AUG, enquanto um aumento da expressão da luciferase nos fragmentos que contem as mutações sequenciais. Sendo que apenas duas experiências foram efetuadas com este fragmento, mais estudos são necessários para determinar se a ausência da uORF2 tem algum efeito na regulação da expressão deste fragmento Podemos então com este trabalho concluir que na região 3’UTR se encontra um loop de degradação constitutivo que está bastante conservado, podendo assim significar que aquela região pode ser importante para a regulação da expressão do gene. Contudo experimentalmente não foi possível isolar das células MC3T3-E1 um fragmento dessa região, podendo ser devido à necessidade destas células de ratinho expressarem esta proteína que está envolvida na comunicação entre osteoblastos e osteoclastos. Experimentalmente podemos também verificar que existem na região 5’UTR do Bmpr1a 3 uORFs que podem, portanto, vir a ter efeito na regulação da expressão do gene, mas mais estudos precisam de ser feitos para confirmar ou não esta atividade.

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Geographic Information Systems The analysis of remotely sensed imagery has become a fundamental task for many environmental centred activities, not just scientific but also management related. In particular, the use of land cover maps depicting a particular study site is an integral part of many research projects, as they are not just a fundamental variable in environmental models but also base information supporting policy decisions. Land cover mapping assisted by supervised classification is today a staple tool of any analyst processing remotely sensed data, insomuch as these techniques allow users to map entire sites of interest in a omprehensive way. Many remote sensing projects are usually interested in a small number of land cover classes present in a study area and not in all classes that make-up the landscape. When focus is on a particular sub-set of classes of interest, conventional supervised classification may be sub-optimal for the discrimination of these specific target classes. The process of producing a non-exhaustive map, that is depicting only the classes of interest for the user, is called specific class mapping. This is the topic of this dissertation. Here, specific class mapping is examined to understand its origins, developments, adoption and current limitations. The main research goal is then to contribute for the understanding and improvement of this topic, while presenting its main constrains in a clear way and proposing enhanced methods at the reach of the non-expert user. In detail, this study starts by analysing the definition of specific class mapping and why the conventional multi-class supervised classification process may yield sub-optimal outcomes. Attention then is turn to the previous works that have tackled this problem. From here a synthesis is made, categorising and characterising previous methodologies. Its then learnt that the methodologies tackling specific class mapping fall under two broad categories, the binarisation approaches and the singe-class approaches, and that both types are not without problems. This is the starting point of the development component of this dissertation that branches out in three research lines. First, cost-sensitive learning is utilised to improve specific class mapping. In previous studies it was shown that it may be susceptible to data imbalance problems present in the training data set, since the classes of interest are often a small part of the training set. As a result the classification may be biased towards the largest classes and, thus, be sub-optimal for the discrimination of the classes of interest. Here cost-sensitive learning is used to balance the training data set to minimise the effects of data imbalance. In this approach errors committed in the minority class are treated as being costlier than errors committed in the majority class. Cost-sensitive approaches are typically implemented by weighting training data points accordingly to their importance to the analysis. By shifting the weight of the data set from the majority class to the minority class, the user is capable to inform the learning process that training data points in the minority class are as critical as the points in the majority class. The results of this study indicate that this simple approach is capable to improve the process of specific class mapping by increasing the accuracy to which the classes of interest are discriminated. Second, the combined use single-class classifiers for specific class mapping is explored. Supervised algorithms for single-class classification are particularly attractive due to its reduced training requirements. Unlike other methods where all classes present in the study site regardless of its relevance for the particular objective to the users, single-class classifiers rely exclusively on the training of the class of interest. However, these methods can only solve specific classification problems with one class of interest. If more classes are important, those methods cannot be directly utilised. Here is proposed three combining methodologies to combine single-class classifiers to map subsets of land cover classes. The results indicate that an intelligent combination of single-class classifiers can be used to achieve accurate results, statistically noninferior to the standard multi-class classification, without the need of an exhaustive training set, saving resources that can be allocated to other steps of the data analysis process. Third, the combined use of cost-sensitive and semi-supervised learning to improve specific class mapping is explored. A limitation of the specific class binary approaches is that they still require training data from secondary classes, and that may be costly. On the other hand, a limitation of the specific class single-class approaches is that, while requiring only training data from the specific classes of interest, this method tend to overestimate the extension of the classes of interest. This is because the classifier is trained without information about the negative part of the classification space. A way to overcome this is with semi-supervised learning, where the data points for the negative class are randomly sampled from the classification space. However that may include false negatives. To overcome this difficult, cost-sensitive learning is utilised to mitigate the effect of these potentially misclassified data points. Cost weights were here defined using an exponential model that assign more weight to the negative data points that are more likely to be correctly labelled and less to the points that are more likely to be mislabelled. The results show that accuracy achieved with the proposed method is statistically non-inferior to that achieved with standard binary classification requiring however much less training effort.

Miguel, I., Navarro, A., Rolim, J., Catalão, J., Silva, J., Painho, M., & Vekerdy, Z. (2016). Land cover monitoring for water resources management in Angola. In Proceedings of Living Planet Symposium 2016 (Vol. SP-740). European Space Agency. The aim of this paper is to assess the impact of improved temporal resolution and multi-source satellite data (SAR and optical) on land cover mapping and monitoring for efficient water resources management. For that purpose, we developed an integrated approach based on image classification and on NDVI and SAR backscattering (VV and VH) time series for land cover mapping and crop's irrigation requirements computation. We analysed 28 SPOT-5 Take-5 images with high temporal revisiting time (5 days), 9 Sentinel-1 dual polarization GRD images and in-situ data acquired during the crop growing season. Results show that the combination of images from different sources provides the best information to map agricultural areas. The increase of the images temporal resolution allows the improvement of the estimation of the crop parameters, and then, to calculate of the crop's irrigation requirements. However, this aspect was not fully exploited due to the lack of EO data for the complete growing season. publishersversion published

The manufacturing process and the behavior of a spring manufactured from an aluminum sheet is described and investigated in this work considering the specifications for the in-service conditions. The spring is intended to be applied in car multimedia industry to replace bolted connections. Among others, are investigated the roles of the constitutive parameters and the hypothesis of evolutive elastic properties with the plastic work in the multi-step forming process and in working conditions. The role of the sheet forming history is also investigated., This research was sponsored by: (a) Portugal Incentive System for Research and Technological Development. Project in co-promotion no 36265/2013 (Project HMIExcel - 2013-2015), and (b) FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 - Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941., info:eu-repo/semantics/publishedVersion

Influences of two types of substrates, natural (macrophyte, Pistia stratiotes) and artificial (plastic screen) were evaluated at 3 differrent densities (10, 20, 30%) on periphyton development, water quality and growth performance of jaraqui (Semaprochilodus insignis). Fish of average initial weight 1.46-1.69 g and length 4.15-4.26 cm stocked at 1/m2 in 46 m2 masonry tanks were grown for 120 days. The tanks were fertilized with urea, triple superphosphate and wheat bran. The types and densities of substrates tested did not drastically influence water quality. Natural substrate harboured higher periphyton biomass (1.48±0.09 mg/cm2) as well as species diversity (28 genera) than the artificial substrate (0.84±0.12 mg/cm2, 20 genera,). Fish in 10% and 20% artificial substrate and 20% natural substrate treatments showed better mean values of body weight (24.64, 23.86, 29.26 g respectively) on termination of the experiment. Fish survival was the lowest in 30% natural substrate (84.1%) and highest in 10% artificial substrate (94.2%). Higher fish biomass was recorded in 20% natural and 10% artificial substrate treatments (25.05 and 21.71 g/m2), which amounts to a four-month yield of 250 and 217 kg/ha in the two treatments. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.

The use of Personal Protective Equipment (PPE) has become a necessity in view of the number of accidents at work that occurred in the past years. The European Community (EU) and the member states are creating strategies aiming the increase of the use of PPE's and consequently the decrease of the number of the accidents at work, decreasing also the number of injuries caused by them and their severity. In this paper, a brief review of safety footwear and its components will be presented focusing on penetration resistant inserts. Additionally, we present a project in development at University of Minho that aims to improve the existent shoes. This project proposes a brand new penetration resistant inserts through a combination of innovative materials., info:eu-repo/semantics/publishedVersion