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- Computational Analysis of Fundus Images: Rule-Based and Scale-Space ModelsPublication . Soares, Ivo Miguel da Fonseca Gravito; Pinheiro, António Manuel Gonçalves; Sousa, Miguel Castelo Branco Craveiro deFundus images are one of the most important imaging examinations in modern ophthalmology because they are simple, inexpensive and, above all, noninvasive. Nowadays, the acquisition and storage of highresolution fundus images is relatively easy and fast. Therefore, fundus imaging has become a fundamental investigation in retinal lesion detection, ocular health monitoring and screening programmes. Given the large volume and clinical complexity associated with these images, their analysis and interpretation by trained clinicians becomes a timeconsuming task and is prone to human error. Therefore, there is a growing interest in developing automated approaches that are affordable and have high sensitivity and specificity. These automated approaches need to be robust if they are to be used in the general population to diagnose and track retinal diseases. To be effective, the automated systems must be able to recognize normal structures and distinguish them from pathological clinical manifestations. The main objective of the research leading to this thesis was to develop automated systems capable of recognizing and segmenting retinal anatomical structures and retinal pathological clinical manifestations associated with the most common retinal diseases. In particular, these automated algorithms were developed on the premise of robustness and efficiency to deal with the difficulties and complexity inherent in these images. Four objectives were considered in the analysis of fundus images. Segmentation of exudates, localization of the optic disc, detection of the midline of blood vessels, segmentation of the vascular network and detection of microaneurysms. In addition, we also evaluated the detection of diabetic retinopathy on fundus images using the microaneurysm detection method. An overview of the state of the art is presented to compare the performance of the developed approaches with the main methods described in the literature for each of the previously described objectives. To facilitate the comparison of methods, the state of the art has been divided into rulebased methods and machine learningbased methods. In the research reported in this paper, rulebased methods based on image processing methods were preferred over machine learningbased methods. In particular, scalespace methods proved to be effective in achieving the set goals. Two different approaches to exudate segmentation were developed. The first approach is based on scalespace curvature in combination with the local maximum of a scalespace blob detector and dynamic thresholds. The second approach is based on the analysis of the distribution function of the maximum values of the noise map in combination with morphological operators and adaptive thresholds. Both approaches perform a correct segmentation of the exudates and cope well with the uneven illumination and contrast variations in the fundus images. Optic disc localization was achieved using a new technique called cumulative sum fields, which was combined with a vascular enhancement method. The algorithm proved to be reliable and efficient, especially for pathological images. The robustness of the method was tested on 8 datasets. The detection of the midline of the blood vessels was achieved using a modified corner detector in combination with binary philtres and dynamic thresholding. Segmentation of the vascular network was achieved using a new scalespace blood vessels enhancement method. The developed methods have proven effective in detecting the midline of blood vessels and segmenting vascular networks. The microaneurysm detection method relies on a scalespace microaneurysm detection and labelling system. A new approach based on the neighbourhood of the microaneurysms was used for labelling. Microaneurysm detection enabled the assessment of diabetic retinopathy detection. The microaneurysm detection method proved to be competitive with other methods, especially with highresolution images. Diabetic retinopathy detection with the developed microaneurysm detection method showed similar performance to other methods and human experts. The results of this work show that it is possible to develop reliable and robust scalespace methods that can detect various anatomical structures and pathological features of the retina. Furthermore, the results obtained in this work show that although recent research has focused on machine learning methods, scalespace methods can achieve very competitive results and typically have greater independence from image acquisition. The methods developed in this work may also be relevant for the future definition of new descriptors and features that can significantly improve the results of automated methods.
- Profiling the athletic career of Portuguese Football Players in last 50 yearsPublication . Monteiro, Ricardo José Vaz Alves; Travassos, Bruno Filipe Rama; Torregrossa, MiquelThis work aimed to identify Key Career Indicators (KCI) that characterize the various stages of athletic development of a football player, as well as their predictive value of competitive level and retiring age. Furthermore, it sought a better understanding of the relationship between some psychological traits and career planning. To this end, three studies were carried out, which sought to: a) describe and identify the weight of the KCI on the competitive level of retirement of football players; b) relate the athletic development of the players and the retiring age of Portuguese football players; c) identify the role of selfefficacy, career goals and athletic identity on the career planning of Portuguese football players. In study 1, results showed that the KCI, age of first registration as a senior player, number of games played over the seasons and age of the last best result achieved, contribute to explain, and predict the competitive level of retirement of Portuguese football players. The results of the model proposed in study 2 highlighted that the KCI identified at the various stages of the athletic development level of a football player contribute to explain 40% of the retiring age the players under analysis. Finally, in study 3, the results revealed that, in general, career planning is positively influenced by the level of self-efficacy of the players through the definition of career goals and negatively influenced by the level of athletic identity. In conclusion, the results suggest that it is possible to monitor some key career indicators that allow a prospective description of the career development of a football player, with implications for the planning and management process. The development of self-efficacy, as well as career goals associated with a balanced management of athletic identity, decisively contribute to better career planning.
- Documentos pré-1975 sobre Timor: antigos, mas não antiquadosPublication . Schouten, Maria Johanna ChristinaA antropologia e o colonialismo português têm um passado em comum. Durante o século XX, os chamados povos indígenas da Ásia e África foram objeto de observação e estudo por numerosos administradores, missionários, militares e cientistas coloniais portugueses. Segue o resumo do posfácio, em língua inglesa: In this book various authors, in their analyses of diverse ethnographic material dating from the colonial period, consider the relationship between anthropology and colonialism on the island of Timor. While the chapters focus on eastern Timor (now Timor-Leste) under Portuguese colonial rule, this Afterword also addresses the western (now Indonesian) part of the island and the ethnographic work carried out in the era of Dutch colonial supremacy, mainly by government officials and missionaries. Hence, some data about western Timor are included in the discussion of themes that are paramount throughout the book, and the use of data on both parts of the Island is recommended for anthropological research. In the final part, mention is made of some Dutch contributions to the ethnography on Timor, and its relationship with the development of theory in anthropology in the 1950s and 1960s.
- Sonho e Tempo: Aproximações à Relação entre Atenção em Vigília e Sonho Lúcido na Fenomenologia de María ZambranoPublication . Pinto, Ana Raquel Rodrigues Loio; Nascimento, André Barata; Sidoncha, Urbano MestreMaría Zambrano afirma que o fenómeno sonho, geralmente vivido como um estado atemporal e infraconsciente, pode transformar-se numa vivência supratemporal e supraconsciente. O meio que permite esta transformação é a vigília, pois permite à pessoa fazer uso do tempo e da atenção para “decifrar” e “assimilar” aquilo que lhe acontece. Portanto, Zambrano considera que o sonho, que ocorre tanto no sono como em vigília, poderá ser compreendido através da atenção. Por sua vez, a filosofia da mente observou em estudos empíricos que um estado de atenção em vigília pode contribuir para o surgimento da atenção no sonho, durante o sono, tornando o sonho lúcido. E, no Budismo Tibetano, existem técnicas de meditação que permitem obter lucidez no sonho. Neste quadro, é descrita uma relação fenomenológica temporal do vaguear da mente e da atenção em vigília com o surgimento do sonho comum e do sonho lúcido, respetivamente, na fenomenologia do sonho de Zambrano. O significado filosófico desta questão assenta na “descoberta da verdade”, que Zambrano considera ocorrer quando o sonho, do sono e da vigília, é compreendido. De modo semelhante, no Budismo Tibetano a atenção permite a compreensão da natureza da mente, de novo a verdade, sob um certo entendimento. Sugere-se que a obtenção de lucidez no sonho, um estado normalmente infraconsciente, é como um degrau para estados de consciência lúcidos, onde a verdade é descoberta pelo desfazer de imagens que a pessoa toma por verdadeiras. Pode ser encontrado, ainda, um seguimento na vivência desta área descurada da vida da pessoa, do sonho, o que Zambrano denomina de sonho melodia, embora não desenvolva o conceito. Ora, o sonho que tem seguimento será enriquecido por uma vigília em que vigora um certo estado de atenção e que, assim, apreende cada vez mais e, por seu turno, enriquecerá a vigília, porque a sucessão apresenta um sentido mais claro. Deste modo, é proposta a possibilidade de dinamizar a capacidade humana de integrar sonho e vigília, que fica estagnada quando o sonho, que é parte da vida, é esquecido. Procura-se, ainda, ultrapassar esta dualidade de sonho e vigília no sentido psicológico, uma vez que é uma cisão por um lado convencionada e prática, mas que pode funcionar contra a vivência integral do humano.
- Exploring how limiting the number of ball touches during small-sided games affects youth football players’ performance across different age groupsPublication . Coutinho, Diogo; Gonçalves, Bruno; Santos, Sara; Travassos, Bruno; Folgado, Hugo; Sampaio, JaimeThis study explored how the number of allowed ball touches per player possession affected the performance of different age groups (U9, U11, U13, U15, U17 and U19) during a Gk þ 4vs4þGk small-sided games. Each day, players randomly performed the following three conditions (for a total of 6 days): i) free-play (FP); ii) maximum of 2 touches (2 T); iii) 1 touch (1 T). Players’ positional data was used to compute time-motion and positional-related variables, while video analysis was used to capture technical performance. In general, no effects were identified in relation to the players distances (team centroid, opponents’ centroid, nearest teammate, and nearest opponent). There were small to moderate decreases in the longitudinal synchronization while playing with 1 T and 2 T in the U9 and U17, but a moderate increase in the U15. There was a general decrease in the distance covered and distance covered while running (small to moderate effects) when playing with limited touches in all age groups. Limiting the touches promoted small to moderate increases in the number of successful passes in the U9, U15, and U17 and a general increase in unsuccessful actions. Overall, playing with limited touches emphasized the passing skill while it also contributed to more unsuccessful actions and lower physical demands. As so, coaches may use the 2 T in young age groups (U9-U13) as they seem less able to successfully cope with 1 T, while using 1 T in older age groups due to their higher ability to interact with environmental information.
- O risco de Morte Súbita em pessoas com Cardiomiopatia HipertróficaPublication . Martins, Nuno Novais da Fonseca; Oliveira, Maria Elisa Cairrão RodriguesIntrodução: A Cardiomiopatia Hipertrófica (CMH) é uma doença congénita autossómica dominante, caracterizada por uma hipertrofia septal assimétrica onde a cavidade ventricular esquerda não apresenta dilatação e há desarranjo das fibras musculares ventriculares, podendo ocorrer arritmias ventriculares malignas, levando a síncope ou mesmo morte. A Morte Súbita Cardíaca (MSC), por sua vez, é uma cessação inesperada de atividade cardíaca, associada a um colapso hemodinâmico e morte em menos de uma hora desde o início dos sintomas numa pessoa sem qualquer condição potencialmente fatal. Estes dois conceitos estão intrinsecamente relacionados dado que a CMH é uma das principais causas cardiovasculares de MSC. Metodologia: Para a realização deste trabalho, efetuou-se a pesquisa na internet de artigos científicos nos últimos 10 anos, relacionados com o tema utilizando como motor de busca o PubMed, Elsevier e Scopus. Foram, também, utilizadas as guidelines da European Society of Cardiology e da American College of Cardiology Foundation/American Heart Association. Objetivos: O objetivo principal deste trabalho foi verificar a gestão do doente com CMH na prevenção da MSC. Conclusão: Têm-se verificado casos de MSC em pessoas com CMH previamente classificadas de baixo risco, o que demonstra uma classificação inadequada do risco do doente. Com isto, conclui-se que é necessária uma modificação das escalas de avaliação de risco de MSC em doentes com CMH, sendo necessária a valorização de outros fatores de risco para que esta categorização dos doentes seja apropriada, de modo a prevenir potenciais complicações.
- Considerations for the use of alloplastic temporomandibular joint replacement in head and neck reconstruction: a review and case report presentationPublication . Fernandes, Raquel Cardoso; Ângelo, David Serrano Faustino; Almeida, Anabela Antunes deOral cancer is the sixth most common cancer in the world. When the complaints initiate, most of these cancers are already in an advanced-stage disease. Multiple modalities are often required in the treatment of oral cancer, including surgical approaches and radiotherapy. One of the most well-known consequences of radiotherapy is osteoradionecrosis. Osteoradionecrosis is when irradiated bone becomes exposed and necrotic through a wound and persists for a minimum of three months. This condition produces late effects on the tissue blood supply, which creates a difficult and inappropriate environment for reconstruction of remaining bone and soft tissue deformities. Several studies have recommended fibula free flaps as the first reconstruction option for these head and neck patients with major mandibular defects and suffering from osteoradionecrosis. Nonetheless, uncertainty emerges when fibula free flaps fail, and salvage procedures do not achieve their purpose. In this present work is discussed the feasibility of alloplastic temporomandibular joint replacement in head and neck patients when submitted to pre- or post-radiotherapy. The effects of radiotherapy in both cases are associated with a higher risk of postoperative infection and exposure, meanwhile there are some successful cases with alloplastic prostheses, even when radiotherapy is used in these patients’ treatment. Additionally, a case report of a head and neck patient is presented. This patient was submitted to several attempts of mandibular reconstruction after mandibular resection and radiotherapy. When all the efforts have failed, an alloplastic temporomandibular joint replacement was proposed. This present work intends to review reconstruction techniques in radiotherapy treatment situations and offer a new approach through a case report presentation.
- Modeling athletic career of football players: Implications for career management and retirementPublication . Monteiro, Ricardo; Monteiro, Diogo; Torregrossa, Miquel; Travassos, BrunoThis study aimed to identify Career Indicators (CIs) over the stages of career development (Initiation/Development, Mastery, and Discontinuation stages) in the retirement stage of Portuguese football players. Three thousand five hundred retired Portuguese football players that played between 1960 and 2018 were considered in this study. A path analysis was performed to identify the standardized direct and indirect effects of the CI at each stage of career development, on Portuguese football players’ retirement age. The proposed model highlighted that the relationship between the CI number of seasons as a youth player, number of seasons as a youth player in top 3 clubs, age of first registration as a senior player, number of seasons as a senior player, number of seasons as a senior player in top 3 clubs, number of total games as a senior player, age of the last best result age achieved, number of games in the retirement season, and discontinuation stage length contribute to explain 40% of the retirement age of Portuguese football players. Results allowed the understanding of the influence of each stage of career development on career length. According to the Holistic Athletic Career Model, it was the first attempt to create a predictive model of CI of athletic variables. Further research should be developed to incorporate some mediator variables such as players’ performance levels and achievement to improve the explanation of the development of football players’ careers and retirement.
- Educação dos Pacientes na Prevenção do Pé DiabéticoPublication . Silva, Gonçalo Pimenta da; Cruz, Isa Maria Rocha; Simões, José Augusto RodriguesIntrodução: A diabetes mellitus é uma das doenças com maior impacto na saúde global pela crescente prevalência e morbi-mortalidade que lhe está associada, assumindo o pé diabético particular destaque entre as complicações da diabetes. A presente monografia procurará enfatizar a importância da adaptação de estratégias inovadoras para um controlo otimizado desta patologia, inclusivamente recorrendo a novas tecnologias. Materiais e Métodos: Foi realizada uma pesquisa nas bases de dados PubMed e Cochrane Library. Na~o foram colocados limites temporais a` pesquisa. Foram selecionados estudos observacionais e de intervenção aleatorizados, que usaram aplicações de telemóvel, equipamentos de monitorização ou programas educacionais para a educação e monitorização dos doentes diabéticos. Foram avaliados os resultados quanto a parâmetros clínicos, analíticos e performance em escalas e questionários sobre adesão, autocuidado, autoeficácia e conhecimento. Resultados: Tendo em conta os parâmetros clínicos, num dos estudos a incidência de úlceras foi significativamente inferior no grupo de terapia avançada, que usa um termómetro digital de infravermelhos para medir e registar as temperaturas em cada pé. A corroborar estes resultados, um estudo que usou um sistema de palmilhas para deteção de pontos de pressão plantar observou a diminuição do número de pessoas com presença de lesões pré-ulcerativas nos pés no grupo experimental. Outro estudo apenas encontrou diferenças estatisticamente significativas no número absoluto de úlceras e não no número de doentes que desenvolveram úlceras, nem no tempo até ao desenvolvimento de úlceras. Em relação aos parâmetros analíticos, apenas um estudo mostrou uma diferença estatisticamente significativa dos valores da HbA1c no grupo de intervenção, em que era usada uma aplicação de telemóvel que permite a leitura da glicemia em tempo real. Quanto aos scores de autoeficácia/autocuidado/conhecimento, verificou-se uma tendência positiva nos grupos de controlo e intervenção, individualmente e entre si. Conclusões: Apesar de se ter mostrado uma tendência positiva na educação e monitorização dos doentes diabéticos, existem ainda poucos estudos que avaliem efetivamente o efeito destas estratégias na incidência e recidiva da ulceração. Para além disso, verifica-se uma grande heterogeneidade, tanto nos objetivos, como nos desenhos dos estudos, nos tipos de intervenção e nas medidas de outcome, não existindo ainda condições que permitam concluir a eficácia da educação dos doentes com ou sem o uso de tecnologia.
- Chitin- and chitosan-based strategies in wound healingPublication . Cabral, Cátia S. D.; Graça, Mariana F. P.; Moreira, André F.; Diogo, Duarte de Melo; Correia, I.J.Nowadays, chronic wounds are still a huge health problem with a high impact on the patients’ quality of life. In this way, the development of an ideal wound dressing is of utmost importance. To accomplish that, researchers have been using natural polymers to produce new types of dressings, that can activate/direct specific cellular responses, leading to an improved healing process. Among the natural polymers, chitin presents notable antibacterial and antiinflammatory properties that are crucial for enhancing the wound healing process. Moreover, chitosan, a deacetylated form of chitin, has been one of the most used biopolymers due to its straightforward processability into different forms, antimicrobial activity, and capacity to promote/accelerate the healing process. This chapter provides an overview of the properties exhibited by chitin and chitosan as well as examples of their application in the development of dressings aimed to improve the healing process.