Comparison of different treatments during acute exacerbations of chronic obstructive pulmonary disease: results of classical vs. network meta-analysis

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Generalized estimating equations vs. repeated-measures ANOVA on the time-course of clinical variables during acute exacerbations of chronic obstructive pulmonary disease

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Learning environments and pedagogical model of an engineering design degree program

This paper presents the theoretical background that supports the use of project-based learning (PBL) in engineering education and relates it to the pedagogical framework implemented in the new first cycle degree program Technology and Product Design offered by the University of Aveiro. The program structure is described focusing on the learning environments used in each course of this interdisciplinary program. The purpose of this paper is to characterize this new curriculum in order to contribute to the discussion about engineering education pedagogy with a complete program implementation experiment. Issues like courses architecture and scope, assessment, student/teacher ratios and group sizes are addressed. Furthermore, students’ perceptions of the learning environments is investigated and compared with their learning results. Ultimately the implications of a student-centred learning curriculum design, based on a PBL strategy, are discussed

Looking for atypical groups of distributions in the context of genomic data

This work addresses the problem of detecting groups of observations (distributions) and flagging those that differ abnormally from the majority of the groups, termed as atypical groups. The proposed method combines a hierarchical classification technique, to identify groups of similar distributions, with a functional outlier detection method, to identify those groups that contain outliers. Groups with outlying observations are forwarded for sub clustering. Once the final partition is obtained, each cluster is represented by a class prototype, whose outlyingness is evaluated according to a functional approach. Clusters with atypical class labels are flagged as atypical groups. The method is applied for the detection of groups of atypical genomic words, based on their distances distributions.publishe

Characterization of the epidemiological curve of the 1st wave of the pandemic: study of the determinants for death and hospitalization due to COVID-19 in Portugal

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus that emerged in China and has since spread rapidly to all countries in the world. The aim of this study is to characterize the peak of the first wave of the pandemic in Portugal using some demographic and clinical determinants. The database studied contains epidemiological surveillance data of COVID-19 from Portugal until June 30, 2020. The peak of the pandemic was determined considering the number of diagnoses, deaths, and hospitalizations over time, and the estimated period for the first wave was between March 19 and April 24. Multivariable logistic regression models were performed to estimate the Odds Ratio (OR) and the respective 95% confidence intervals (95% CI) for this period and for each of the variables considered in relation to both study outcomes: mortality (5.8%) and hospitalization (18.8%). The main risk factors considered for the mortality outcome were: Age Group (≥ 80 years: OR = 11.98; 65-79 years: OR = 4.06; reference group: <64 years), Hospitalization (OR = 6.48) and Comorbidities (OR = 5.74). For the outcome hospitalization, the main risk factors were: Age Group (≥ 80 years: OR = 8.54; 65-79 years: OR = 3.90; reference group: <64 years), male gender (OR= 1.58) and Comorbidities (OR = 5.19). The proposed models presented high area under the curve (AUC) results (mortality: AUC=91.1%; and hospitalization: AUC=84.5%), with small amplitudes in the 95% CI. The present study demonstrated that, overall, the major risk factors associated with worse prognostics of COVID-19 were advanced age (over 65 years), and the existence of comorbidities. For the risk of hospitalizations, the male gender was also a significant risk factor.in publicatio

Sinais simbólicos e aplicações em genómica

Doutoramento em Engenharia ElectrotécnicaEsta dissertação surge no contexto do processamento de sinais simbólicos com o objectivo específico de contribuir para o conhecimento da estrutura das sequências de DNA. A localização automática de genes foi um dos problemas biológicos que motivou o desenvolvimento deste trabalho. A compressão de sequências genéticas, quer para reduzir o espaço de armazenamento quer para obtenção de modelos das mesmas, foi outra das motivações. Com o objectivo de contribuir para melhorar uma das técnicas frequentemente usadas na localização automática de genes são comparadas metodologias de análise espectral para sequências simbólicas. Também se discute a validade de aplicação de metodologias de análise espectral às sequências simbólicas e apresenta-se um novo método baseada na função de autocorrelação simbólica. Uma característica que usualmente é tomada para identificação de genes é o tamanho da risca espectral que reflecte a periodicidade de período três. Apresenta-se um algoritmo rápido baseado em contadores de símbolos para cálculo de várias riscas espectrais, e em particular da risca de período três. São também enunciadas e analisadas propriedades associadas ao tamanho de algumas riscas e à redundância espectral. Por último, desenvolve-se uma técnica para compressão de sequências genéticas baseada num modelo de três estados. Em regiões codificantes do DNA esta técnica leva em geral a melhores resultados do que as actuais técnicas de compressão.This dissertation addresses the problem of processing sequences of symbols, and has the specific aim of contributing to the analysis and modeling of DNA sequences. This work was partly motivated by the problem of automatic gene location. Another motivation was the compression of genetic sequences, both for the purpose of reducing the required storage and for determining good DNA models. The main methodologies of spectral analysis of symbolic sequences are compared. The application of spectral analysis methods to the symbolic sequences is discussed and a new method based on the symbolic autocorrelation function is presented. One feature that is often used in gene identification is the size of the Fourier coefficient that reflects periodicity of period three. A fast algorithm for the calculation of Fourier coefficients, based on symbol counters, was developed. Some properties associated with the size of some spectral coefficients and spectral redundancy are discussed. Finally, a technique based on a model with three states was developed to compress genetic sequences. In protein-coding regions this technique leads in general to better results than the state-of-the-art DNA compression techniques

Análise estatística da linguagem genética

O objectivo principal deste trabalho é analisar a linguagem genética no contexto dos codões, ou seja, da parte codificante dos genes responsável pela produção de proteínas. Concretamente, pretende-se decifrar leis gerais que governem a tradução do mRNA pelo ribossoma. Para esse efeito foram utilizados dados genéticos de duas espécies distintas, que partilham todavia o mesmo ancestral: Candida albicans e Saccharomyces cerevisiae. No presente estudo são empregues diferentes metodologias e modelos estatísticos adequados a dados de natureza discreta; nomeadamente, Análise de Tabelas de Contingência, Análise Classificatória, Análise em Componentes Principais, Cadeias de Markov, Análise de Zipf, Critério de Informação Bayesiana e Teoria da Informação. Com as Tabelas de Contingência, averigua-se, do ponto de vista da independência e associação, o comportamento de pares de codões ou nucleótidos, justapostos ou espaçados. As Análises Classificatória e em Componentes Principais permitem estudar, de forma exploratória, a preferência de um codão face ao codão justaposto e aos seus nucleótidos constituíntes. As cadeias de Markov são aplicadas com o objectivo de averiguar a adequação do modelo no sequenciamento dos codões. A Análise de Zipf visa estimar a respectiva lei e averiguar a existência de correlações de longo alcance entre os codões sequenciados. Para estimar a ordem da cadeia de Markov no sequenciamento de codões é usado o Critério de Informação Bayesiana. A Teoria da Informação é aplicada com o intuito de obter valores de entropia no conjunto das sequências de código. Tudo leva a crer que os textos genéticos são estruturas bem organizadas, em que existe alguma associação entre um dado codão e os símbolos (codões ou nucleótidos) justapostos ou espaçados. Esta associação decresce à medida que o espaçamento aumenta. ABSTRACT: The main aim of this work is to analyse the genetic language at the codon context. In other words, the coding part of the genes responsible for protein production is studied with the goal of deciphering general laws which govern the mRNA translation by the ribosome. For this purpose, it was used genetic data from two species that share the same ancestral: Candida albicans e Saccharomyces cerevisiae. In this study different methodologies and statistical models are employed, namely: Contingency Tables, Cluster Analysis, Principal Components Analysis, Markov Chains, Zipf Analysis, Bayesian Information Criterion and Information Theory. With the Contingency Tables, we investigate, from the independency and association point of view, the behaviour of the codon or nucleotide pairs, placed side by side or spaced. The Cluster Analysis and Principal Component Analysis allow studying, in an exploratory way, the preference of a codon relative to its adjacent and its nucleotides. The Markov Chains are applied with the goal of investigate the fitting of the model in the codon sequencing. The Zipf Analysis aims to estimate the respective law and examine the existence of long range correlations among sequencing codons. The Bayesian Information Criterion is applied to estimate the order of the Markov chain in the codon sequencing. Finally, the Information Theory is used to obtain entropy values for the set of code sequences. As a result of this study, we are inclined to think that genetic texts are well organized structures, with some association between a given codon and contiguous or spaced symbols (codons or nucleotides). That association decreases as the spacing goes by

Clinical characteristics of patients with chronic obstructive pulmonary disease (COPD): are they different

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Identification of clinical phenotypes of patients with Chronic Obstructive Pulmonary Disease (COPD)

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Drug–drug interaction in elderly patients with cancer

Elderly cancer patients have a high risk of exposure to potential drug-drug interactions (pDDIs), given the therapeutic complexity to which they are subjected. The study of pDDIs is very important to enable more effective treatments, with the least possible number of complications.The aim of this study was to identify and characterize pDDIs in elderly cancer patients treated at the Day Hospital of IPO-Portoinfo:eu-repo/semantics/publishedVersio