Miguel Felgueiras

Prof. Dr. Miguel Felgueiras

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Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 August 2023 in Vaccines
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Journal Article
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João Paulo MartinsJoão Paulo Martins
João Paulo Martins
MSMarlene Santos
Marlene Santos
AMAndré Martins
André Martins
Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras
Rui SantosRui Santos
Rui Santos
Influenza is a respiratory disease caused by the influenza virus, which is highly transmissible in humans. This paper presents a systematic review and meta-analysis of randomized controlled trials (RCTs) and test-negative designs (TNDs) to assess the vaccine effectiveness (VE) of seasonal influenza vaccines (SIVs) in humans aged 15 to 64 years. An electronic search to identify all relevant studies was performed. The outcome measure of interest was VE on laboratory-confirmed influenza (any strain). Quality assessment was performed using the Cochrane risk-of-bias tool for RCTs and the ROBINS-I tool for TNDs. The search identified a total of 2993 records, but only 123 studies from 73 papers were included in the meta-analysis. Of these studies, 9 were RCTs and 116 were TNDs. The pooled VE was 48% (95% CI: 42–54) for RCTs, 55.4% (95% CI: 43.2–64.9) when there was a match between the vaccine and most prevalent circulating strains and 39.3% (95% CI: 23.5–51.9) otherwise. The TNDs’ adjusted VE was equal to 39.9% (95% CI: 31–48), 45.1 (95% CI: 38.7–50.8) when there was a match and 35.1 (95% CI: 29.0–40.7) otherwise. The match between strains included in the vaccine and strains in circulation is the most important factor in the VE. It increases by more than 25% when there is a match with the most prevalent circulating strains. The laboratorial method for confirmation of influenza is a possible source of bias when estimating VE.

15 August 2012 in GEM - International Journal on Geomathematics
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Journal Article
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Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras

1 January 2014 in AIP Conference Proceedings
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Conference Paper
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Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras
Rui SantosRui Santos
Rui Santos
João Paulo MartinsJoão Paulo Martins
João Paulo Martins
We investigate Gaussian mixtures with independent components, whose parameters are numerically estimated. A decomposition of a Gaussian mixture is presented when the components have a common variance. We introduce a shifted and scaled t-Student distribution as an approximation for the distribution of Gaussian mixtures when their components have a common mean and develop a hypothesis test for testing the equality of the components means. Finally, we analyse the fitness of the approximate model to the logarithmic daily returns of the Portuguese stock index PSI-20.

1 July 2012 in ADCAIJ: Advances in Distributed Computing and Artificial Intelligence Journal
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Journal Article
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APAntónio Pereira
António Pereira
FFFilipe Felisberto
Filipe Felisberto
LMLuis Maduro
Luis Maduro
Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras
In this work, a distributed system for fall detection is presented. The proposed system was designed to monitor activities of the daily living of elderly people and to inform the caregivers when a falls event occurs. This system uses a scalable wireless sensor networks to collect the data and transmit it to a control center. Also, an intelligent algorithm is used to process the data collected by the sensor networks and calculate if an event is, or not, a fall. A statistical method is used to improve this algorithm and to reduce false positives. The system presented has the capability to learn with past events and to adapt is behavior with new information collected from the monitored elders. The results obtained show that the system has an accuracy above 98%.

11 December 2024 in Vaccines
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Journal Article
Open access
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APAna Pereira
Ana Pereira
CPCláudia Pinho
Cláudia Pinho
AOAdriana Oliveira
Adriana Oliveira
Rui SantosRui Santos
Rui Santos
Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras
João Paulo MartinsJoão Paulo Martins
João Paulo Martins
Background: The World Health Organization estimates that currently available vaccines prevent 2 to 3 million deaths worldwide each year. Preventing infectious diseases is an important public health priority to ensure healthy ageing and improve quality of life. This study’s aim is to identify the best strategies to increase vaccination coverage in the elderly. Methods: A systematic review and meta-analysis were carried out, including a bibliographic search in the PubMed and Scopus databases. Studies in older people (60 years or older) on any type of intervention aimed at increasing vaccination coverage were included. The effect of the intervention was measured using the odds ratio (OR). Results: After applying the selection criteria, 20 studies were identified: 17 on influenza vaccines and 3 on other vaccines. Educational strategies obtained an OR = 1.63 (95% CI: 1.22–2.19, I2 = 0.59). Medical counselling obtained an OR = 3.13 (95% CI: 0.60–16.37, I2 = 0.95). Writing strategies obtained an OR = 1.14 (95% CI: 0.99–1.32, I2 = 0.93). Few studies reported the effect of free vaccination. Conclusions: The educational strategies proved to be more effective than the others in this study. Free vaccination and age may have important roles. Further studies are needed as research in this area remains limited.

1 January 2012 in AIP Conference Proceedings
Verified
Conference Paper
Closed access
Miguel FelgueirasMiguel Felgueiras
Miguel Felgueiras
João Paulo MartinsJoão Paulo Martins
João Paulo Martins
Rui SantosRui Santos
Rui Santos
Allowing weights w∈]−1;1]\{0} , pseudo-convex mixtures increase usual mixtures flexibility. The finite mixtures with negative components are investigated for distribution families closed under minimization. The main purpose is to define these mixtures and to study their properties.