Fabrication and characterization of transparent conductive oxide surface sensors for electrocorticography – TrECoG

Understanding how the brain works has been one of the greatest goals of mankind. This desire fuels the scientific community to pursue novel techniques able to acquire the complex information produced by the brain at any given moment. The Electrocorticography (ECoG) is one of those techniques. By placing conductive electrodes over the dura, or directly over the cortex, and measuring the electric potential variation, one can acquire information regarding the activation of those areas. In this work, transparent ECoGs, (TrECoGs) are fabricated through thin film deposition of the Transparent Conductive Oxides (TCOs) Indium-Zinc-Oxide (IZO) and Gallium-Zinc-Oxide (GZO). Five distinct devices have been fabricated via shadow masking and photolithography. The data acquired and presented in this work validates the TrECoGs fabricated as efficient devices for recording brain activity. The best results were obtained for the GZO- based TrECoG, which presented an average impedance of 36 kΩ at 1 kHz for 500 μm diameter electrodes, a transmittance close to 90% for the visible spectrum and a clear capability to detect brain signal variations. The IZO based devices also presented high transmittance levels (90%), but with higher impedances, which ranged from 40 kΩ to 100 kΩ

Arbitrary bi-dimensional finite strain crack propagation

In the past two decades numerous numerical procedures for crack propagation have been developed. Lately, enrichment methods (either local, such as SDA or global, such as XFEM) have been applied with success to simple problems, typically involving some intersections. For arbitrary finite strain propagation, numerous difficulties are encountered: modeling of intersection and coalescence, step size dependence and the presence of distorted finite elements. In order to overcome these difficulties, an approach fully capable of dealing with multiple advancing cracks and self-contact is presented (see Fig.1). This approach makes use of a coupled Arbitrary Lagrangian-Eulerian method (ALE) and local tip remeshing. This is substantially less costly than a full remeshing while retaining its full versatility. Compared to full remeshing, angle measures and crack paths are superior. A consistent continuationbased linear control is used to force the critical tip to be exactly critical, while moving around the candidate set. The critical crack front is identified and propagated when one of the following criteria reaches a material limiting value: (i) the stress intensity factor; or (ii) the element-ahead tip stress. These are the control equations. The ability to solve crack intersection and coalescence problems is shown. Additionally, the independence from crack tip and step size and the absence of blade and dagger-shaped finite elements is observed. Classic benchmarks are computed leading to excellent crack path and load-deflection results, where convergence rate is quadratic

Humanismo, diáspora e ciência: séculos XVI e XVII: estudos, catálogo, exposição

Resumo indisponível

Monitoring Sleep and Heart Rate in Female Soccer Cardiac autonomic function and sleep patterns after training sessions and matches in female soccer players

A presente dissertação teve como objetivo investigar o impacto de sessões de treino e de jogos oficiais, realizados em diferentes locais e horas do dia na atividade da função autonómica cardíaca e nos padrões do sono em jogadoras do futebol feminino de diferentes níveis competitivos (elite e semiprofissionais), durante a época desportiva e durante um torneio internacional. No primeiro estudo, foi investigada a sensibilidade da variabilidade da frequência cardíaca (VFC) noturna para avaliar os efeitos de sessões de treino realizadas à noite na função autonómica cardíaca em jogadoras semiprofissionais de futebol. Apesar dos treinos realizados à noite não parecerem influenciar as slow-wave sleep episode (SWSE) e os índices da VFC analisados hora-em-hora, ambos os métodos (SWSE e índices da VFC analisados hora-em-hora) mostraram ser medidas de VFC confiáveis, sugerindo que a VFC durante a noite poderá ser sensível (ex. alta capacidade de resposta interna) à resposta aos treinos e jogos. Dado que no primeiro estudo os padrões de sono não foram quantificados através de métodos objetivos, como a actigrafia, foram realizados dois estudos observacionais e longitudinais adicionais em que foram incluídos estes métodos, para avaliar o sono e a VFC noturna em jogadoras semiprofissionais de futebol. Estes estudos permitiram concluir que o horário das sessões (sessões de treino realizadas à noite e os jogos realizados durante o dia) e o local dos jogos (jogos em casa vs. fora de casa) podem causar perturbações no padrão de sono e/ou na atividade da função autonómica cardíaca em jogadoras de futebol. Finalmente, considerando a importância da abordagem individualizada na análise do sono e da VFC noturna após cargas de treino e de jogo, foram realizados um quarto (jogadoras de elite) e quinto (jogadoras semiprofissionais) estudos, focando-se especificamente na análise individual da VFC e dos padrões de sono. Os resultados destes estudos revelaram uma considerável variação individual no sono e da VFC, assim como das cargas de treino e de jogo, informação que deve ser considerada na prescrição de sessões de treino e/ou jogos. Os resultados da análise observacional da função autonómica cardíaca noturna, dos padrões de sono, e das cargas de treino e de jogo em jogadoras de futebol realizada na presente tese, podem auxiliar treinadores e profissionais clínicos a identificar perturbações da VFC e do sono após treinos e jogos de futebol, o que deverá constituir-se como informação relevante aquando da prescrição individual de cargas de treino e do tempo de jogo no futebol feminino.The present thesis aims to investigate the impact of training sessions and official matches performed at different times of the day and in different locations on autonomic cardiac function and sleep patterns of female soccer players from different competitive levels (elite and semi-professional), during competitive in-season and during an international tournament. The first study investigated the sensitivity of nocturnal heart rate variability (HRV) to evaluate the effects of late-night soccer training sessions on nocturnal autonomic cardiac function of semi-professional female players. Although late-night soccer training did not appear to affect slow-wave sleep episodes (SWSE) and "hour-by-hour" HRV indices analysed, the implementation of both methods resulted in reliable HRV measures, suggesting that overnight HRV could be sensitive (i.e., high-internal responsiveness) to training and matches responses in female soccer players. Since in the first study sleep patterns were not quantified using objective methods such as actigraphy, we conducted two additional observational and longitudinal studies, where these methods were included to assess nocturnal HRV and sleep in semi-professional female players. These studies led to the conclusion that the training and match schedule (i.e., night-training sessions and day matches) and match location (i.e., home-matches vs. away-matches) may cause disruption in sleep patterns and/or in autonomic cardiac activity. Finally, and considering the importance of an individualized approach in the analysis of sleep and nocturnal HRV from training and match load, a fourth (with elite female players) and fifth (with semi-professionals female players) studies were conducted focusing on individual HRV and sleep patterns. The results of these studies revealed a substantial individual variation in sleep and HRV, as well in training and match load, information that should be considered when prescribing training sessions and/or matches in women's soccer. The results of the observational analysis of nocturnal cardiac autonomic function, sleep patterns, and training and match load in female soccer players conducted in this thesis may help coaches and clinical practitioners to identify HRV and sleep disorders after training and matches, which may constitute relevant information to individually prescribe training load and playing time in female soccer players

Tributyltin chloride disrupts glucose and lipid homeostasis on Wistar male rats

Tributyltin chloride is still a relevant water and seafood pollutant, as reported for some sites of Mediterranean and Iberian coastal waters. We evaluated TBT metabolic effect in Wistar male rats, after administration of a repeated oral dose of 8.5mg/L in ethanol 0.25%, during 28 days, according to DIR96/54/EC. Groups of six animals, individually caged, were daily observed for fast blood glycaemia and semi-quantitative urine analysis. Glycaemic levels were significantly lower on the test group along the assay, showing a tendency for fasting hypoglycaemia. Urine analysis showed the presence of ketonic bodies in test group during the treatment. At the end of test period, animals were euthanized and serum analysis was performed revealing a significant increment of cholesterol and HDL-cholesterol (9.3% and 6.7%, respectively) and a non-significant increment on triglycerides content. These results suggest that TBT disrupted glucose and lipid homeostasis. Accordingly, and considering TBT a new member of environmental obesogen family, it is most relevant to reassess the effect of chronic exposure to low doses of this pollutant

An embedded formulation with conforming

Use of strong discontinuities with satisfaction of compatibilit

ONLINE SOCIAL NETWORKS AND WORKPLACES: NEW AND OLD CHALLENGES

Abstract text, In recent years the growth in the use of new technologies, especially the internet, has given birth to new problems that deserve to be evaluated. The use of technologies of Web 2.0 poses new challenges as to the powers of employers in using the information disclosed by the employees. The new web phase in which we live today offered an active role to the user, removing him from the shade of a passive position. This mutation of borders created new interaction paradigms insofar as the notion of time and space was altered, which could lead to serious consequences as far as the utilization of online social networks is concerned as well as its impact on the employment relationship. The boundary between what may or may not be published by the employee on online social networks like facebook, twitter or blogs is not always clear. But, the employee’s privacy concerning information available in online social networks which can be used by the employer within the employment relationship, also deserves protection. In this article, we intend to analyze the characterization of online social network on the web 2.0 in order to better understand, at a second stage, the effects of its use in the working relationship

ONLINE SOCIAL NETWORKS AND WORKPLACES: NEW AND OLD CHALLENGES

Abstract text, In recent years the growth in the use of new technologies, especially the internet, has given birth to new problems that deserve to be evaluated. The use of technologies of Web 2.0 poses new challenges as to the powers of employers in using the information disclosed by the employees. The new web phase in which we live today offered an active role to the user, removing him from the shade of a passive position. This mutation of borders created new interaction paradigms insofar as the notion of time and space was altered, which could lead to serious consequences as far as the utilization of online social networks is concerned as well as its impact on the employment relationship. The boundary between what may or may not be published by the employee on online social networks like facebook, twitter or blogs is not always clear. But, the employee’s privacy concerning information available in online social networks which can be used by the employer within the employment relationship, also deserves protection. In this article, we intend to analyze the characterization of online social network on the web 2.0 in order to better understand, at a second stage, the effects of its use in the working relationship

Recuperação e identificação de momentos em imagens

In our modern society almost anyone is able to capture moments and record events due to the ease accessibility to smartphones. This leads to the question, if we record so much of our life how can we easily retrieve specific moments? The answer to this question would open the door for a big leap in human life quality. The possibilities are endless, from trivial problems like finding a photo of a birthday cake to being capable of analyzing the progress of mental illnesses in patients or even tracking people with infectious diseases. With so much data being created everyday, the answer to this question becomes more complex. There is no stream lined approach to solve the problem of moment localization in a large dataset of images and investigations into this problem have only started a few years ago. ImageCLEF is one competition where researchers participate and try to achieve new and better results in the task of moment retrieval. This complex problem, along with the interest in participating in the ImageCLEF Lifelog Moment Retrieval Task posed a good challenge for the development of this dissertation. The proposed solution consists in developing a system capable of retriving images automatically according to specified moments described in a corpus of text without any sort of user interaction and using only state-of-the-art image and text processing methods. The developed retrieval system achieves this objective by extracting and categorizing relevant information from text while being able to compute a similarity score with the extracted labels from the image processing stage. In this way, the system is capable of telling if images are related to the specified moment in text and therefore able to retrieve the pictures accordingly. In the ImageCLEF Life Moment Retrieval 2020 subtask the proposed automatic retrieval system achieved a score of 0.03 in the F1-measure@10 evaluation methodology. Even though this scores are not competitve when compared to other teams systems scores, the built system presents a good baseline for future work.Na sociedade moderna, praticamente qualquer pessoa consegue capturar momentos e registar eventos devido à facilidade de acesso a smartphones. Isso leva à questão, se registamos tanto da nossa vida, como podemos facilmente recuperar momentos específicos? A resposta a esta questão abriria a porta para um grande salto na qualidade da vida humana. As possibilidades são infinitas, desde problemas triviais como encontrar a foto de um bolo de aniversário até ser capaz de analisar o progresso de doenças mentais em pacientes ou mesmo rastrear pessoas com doenças infecciosas. Com tantos dados a serem criados todos os dias, a resposta a esta pergunta torna-se mais complexa. Não existe uma abordagem linear para resolver o problema da localização de momentos num grande conjunto de imagens e investigações sobre este problema começaram há apenas poucos anos. O ImageCLEF é uma competição onde investigadores participam e tentam alcançar novos e melhores resultados na tarefa de recuperação de momentos a cada ano. Este problema complexo, em conjunto com o interesse em participar na tarefa ImageCLEF Lifelog Moment Retrieval, apresentam-se como um bom desafio para o desenvolvimento desta dissertação. A solução proposta consiste num sistema capaz de recuperar automaticamente imagens de momentos descritos em formato de texto, sem qualquer tipo de interação de um utilizador, utilizando apenas métodos estado da arte de processamento de imagem e texto. O sistema de recuperação desenvolvido alcança este objetivo através da extração e categorização de informação relevante de texto enquanto calcula um valor de similaridade com os rótulos extraídos durante a fase de processamento de imagem. Dessa forma, o sistema consegue dizer se as imagens estão relacionadas ao momento especificado no texto e, portanto, é capaz de recuperar as imagens de acordo. Na subtarefa ImageCLEF Life Moment Retrieval 2020, o sistema de recuperação automática de imagens proposto alcançou uma pontuação de 0.03 na metodologia de avaliação F1-measure@10. Mesmo que estas pontuações não sejam competitivas quando comparadas às pontuações de outros sistemas de outras equipas, o sistema construído apresenta-se como uma boa base para trabalhos futuros.Mestrado em Engenharia Eletrónica e Telecomunicaçõe

The Spatial Ideology for Brazilian national State constitution

Revista A1 InternacionalNo debate sobre a construção do Estado nacional brasileiro, partimos do pressuposto de que esse processo consolidou-se no cerne de uma valorização fragmentária de suas variantes estéticas, conformando uma controversa ideologia espacial de sentido identitário à nação. Progresso, modernização e integração territorial emergem como palavras de ordem no elo entre a nação imaginada, no Brasil Imperial, e a nação tal como se concretiza, ao longo do século XX, apesar do discurso e das ações em resgate à cultura síntese de brasilidade. Evidencia-se, nesse escopo, uma tendência a se pensar a nação mais como produto cultural de uma elite (fragmentos de cidades coloniais e do barroco consagrados) do que por meio de símbolos da formação de territórios híbridos representantes da totalidade de seus construtores: os antagônicos protagonistas. _________________________________________________________________________________ RESUMENEn el debate sobre la construcción del Estado nacional brasileño partimos del presupuesto de que ese proceso se consolidó en el centro de una valoración fragmentada de sus variantes estéticas, conformando una ideologia espacial controvertida que da sentido de identidade a la nación. Progreso, modernización e integración territorial emergen como palabras de orden en el enlace entre la nación imaginada, en el Brasil Imperial, y la nación tal y como se concreta a lo largo del siglo veinte, a pesar del discurso y de las acciones de rescate de la cultura que sintetiza lo que se considera brasileño. Se evidencia, en ese objetivo, una tendencia a pensar la nación más como producto cultural de una élite (fragmentos de ciudades coloniales y del barroco consagrados) que a través de lós símbolos de la formación de territórios híbridos, que son representantes de la tatilidad de sus constructores, a su vez, lós protagonistas antagônicos. _________________________________________________________________________________ ABSTRACTIn the debate on Brazilian national state construction, we assume that this process was consolidated at the core of a fragmentary valorization of its aesthetic variants, forming a controversial spatial ideology with sense of identity to the nation. Progress, modernization and territorial integration emerge as watchwords on the link between the imagined nation in Imperial Brazil, and the nation as it concretizes itself throughout the twentieth century, although the speech and actions for rescue of brazilianness culture. It becomes evident, in that scope, a tendency to think the nation more as a cultural product of an elite (established pieces of colonial towns and baroque) than think it by symbols of hybrid territories formation representing the totality of its builders: the antagonistic protagonists