Thought-controlled games with brain-computer interfaces

Nowadays, EEG based BCI systems are starting to gain ground in games for health research. With reduced costs and promising an innovative and exciting new interaction paradigm, attracted developers and researchers to use them on video games for serious applications. However, with researchers focusing mostly on the signal processing part, the interaction aspect of the BCIs has been neglected. A gap between classification performance and online control quality for BCI based systems has been created by this research disparity, resulting in suboptimal interactions that lead to user fatigue and loss of motivation over time. Motor-Imagery (MI) based BCIs interaction paradigms can provide an alternative way to overcome motor-related disabilities, and is being deployed in the health environment to promote the functional and structural plasticity of the brain. A BCI system in a neurorehabilitation environment, should not only have a high classification performance, but should also provoke a high level of engagement and sense of control to the user, for it to be advantageous. It should also maximize the level of control on user’s actions, while not requiring them to be subject to long training periods on each specific BCI system. This thesis has two main contributions, the Adaptive Performance Engine, a system we developed that can provide up to 20% improvement to user specific performance, and NeuRow, an immersive Virtual Reality environment for motor neurorehabilitation that consists of a closed neurofeedback interaction loop based on MI and multimodal feedback while using a state-of-the-art Head Mounted Display.Hoje em dia, os sistemas BCI baseados em EEG estão a começar a ganhar terreno em jogos relacionados com a saúde. Com custos reduzidos e prometendo um novo e inovador paradigma de interação, atraiu programadores e investigadores para usá-los em vídeo jogos para aplicações sérias. No entanto, com os investigadores focados principalmente na parte do processamento de sinal, o aspeto de interação dos BCI foi negligenciado. Um fosso entre o desempenho da classificação e a qualidade do controle on-line para sistemas baseados em BCI foi criado por esta disparidade de pesquisa, resultando em interações subótimas que levam à fadiga do usuário e à perda de motivação ao longo do tempo. Os paradigmas de interação BCI baseados em imagética motora (IM) podem fornecer uma maneira alternativa de superar incapacidades motoras, e estão sendo implementados no sector da saúde para promover plasticidade cerebral funcional e estrutural. Um sistema BCI usado num ambiente de neuro-reabilitação, para que seja vantajoso, não só deve ter um alto desempenho de classificação, mas também deve promover um elevado nível de envolvimento e sensação de controlo ao utilizador. Também deve maximizar o nível de controlo nas ações do utilizador, sem exigir que sejam submetidos a longos períodos de treino em cada sistema BCI específico. Esta tese tem duas contribuições principais, o Adaptive Performance Engine, um sistema que desenvolvemos e que pode fornecer até 20% de melhoria para o desempenho específico do usuário, e NeuRow, um ambiente imersivo de Realidade Virtual para neuro-reabilitação motora, que consiste num circuito fechado de interação de neuro-feedback baseado em IM e feedback multimodal e usando um Head Mounted Display de última geração

Development of a localized drug delivery system with chitosan and ferromagnetic nanoparticles produced by wetspinning for cancer treatment

Dissertação de mestrado integrado em Biomedical Engineering Biomaterials, Rehabilition and BiomechanicsO cancro é uma das principais causas de mortalidade no mundo, depois das doenças cardiovasculares. Assim, há uma necessidade urgente de desenvolver novas estratégias para melhorar a eficácia da prevenção, diagnóstico e tratamento desta patologia. Uma das terapias estudadas para tal na atualidade é a hipertermia. Este procedimento baseia- -se no aumento da temperatura para 40-43 °C do tecido corporal para danificar e destruir as células cancerígenas ou torná-las mais suscetíveis aos efeitos de outras terapias como a radio ou a quimioterapia. Recentemente, e devido aos avanços científicos na área da nanotecnologia, surge o conceito de hipertermia magnética que se baseia na utilização de nanopartículas magnéticas. Apesar das diversas vantagens de utilizar nanopartículas, estas podem apresentar alguma dificuldade em alcançar os tecidos específicos a tratar e, devido ao comum processo de formação de agregados, a sua aplicabilidade pode tornar-se difícil. No sentido de ultrapassar estas limitações, as nanopartículas podem ser incorporadas em sistemas de entrega localizada, nomeadamente compostos por fibras, capazes de atuar como agentes terapêuticos localizados. Sendo assim, este trabalho teve como objetivo desenvolver novos filamentos por wetspinning capazes de serem utilizados na construção e design de estruturas fibrosas de entrega localizada de agentes bioativos. Vários parâmetros da técnica de wetspinning foram otimizados para obter os melhores filamentos, sendo que os melhores foram obtidos utilizando uma taxa de fluxo de 1 mL/min, uma agulha de 0.41 mm de diâmetro e um banho de coagulação de 1M de hidróxido de sódio. As fibras obtidas com melhores resultados mecânicos foram produzidas com uma formulação otimizada de 3 %(m/v) de óxido de polietileno com 3 %(m/v) de quitosano em 12 %(v/v) de ácido acético. O banho de crosslinking também foi otimizado, sendo que se utilizou um banho de trifosfato de sódio a 1 %(v/v) durante 4 horas. As nanopartículas ferromagnéticas foram então sintetizadas usando o método de co-precipitação e foram introduzidas nas fibras em diferentes percentagens. Os filamentos funcionalizados com 2 %(m/v) de nanopartículas mostraram o melhor desempenho mecânico, melhorando também a estabilidade estrutural do sistema ao longo do tempo.Cancer is one of the leading causes of mortality in the world, after cardiovascular diseases. Thus, there is an urgent need to develop new strategies to improve the effectiveness of prevention, diagnosis and treatment of this disease. One of the therapies currently being studied for this is hyperthermia. This procedure is based on increasing the temperature to 40-43 °C of the body tissue to damage and destroy cancer cells or make them more susceptible to the effects of other therapies such as radio or chemotherapy. Recently, and due to scientific advances in nanotechnology, the concept of magnetic hyperthermia has emerged, which is based on the use of magnetic nanoparticles. Despite the several advantages of using nanoparticles, these may present some difficulty in reaching the specific tissues to be treated and, due to the common process of aggregate formation, their applicability may become difficult. In order to overcome these limitations, nanoparticles can be incorporated into localized delivery systems, namely composed of fibres, capable of acting as localized therapeutic agents. Therefore, this work aimed to develop new filaments by wetspinning that can be used in the construction and design of fibrous structures for localized delivery of bioactive agents. Several parameters of the wetspinning technique were optimized to obtain the best filaments, and the best ones were obtained using a flow rate of 1 mL/min, a 0.41 mm diameter needle, and a 1M sodium hydroxide coagulation bath. The fibres obtained with the best mechanical results were produced with an optimized formulation of 3 %(w/v) polyethylene oxide with 3 %(w/v) chitosan in a 12 %(v/v) acetic acid aqueous solution. The crosslinking bath was also optimized, and a 1 %(v/v) sodium triphosphate bath was used for 4 hours. Ferromagnetic nanoparticles were then synthesized using the co-precipitation method and were introduced into the fibres in different percentages. The filaments functionalized with 2 %(w/v) nanoparticles showed the best mechanical performance, also improving the structural stability of the system over time

Learning roadmap studio : new approaches and strategies for efficient learning and training processes

Learning systems have emerged in a set of different information systems, oriented for different kinds of organizations and institutions, such as learning management systems, knowledge management systems and learning content management systems, which can be integrated or merged with others. From past experience, it has been denoted that strategies and pedagogical processes are tasks that can be created, enriched and boosted by actors who participate in learning and training processes: course managers, teachers and students. The challenge posed to the different actors involved also accelerates the changes that have been happening in education and training, empowering a society based on knowledge. Initiatives such as eLearning (EU Comission 2000), eLearningEurope, eTwinning and Education Observatories are an evidence of this challenge. Platforms, applications, tools and systems must respond to challenges that those actors face nowadays: heterogeneous target audiences, in terms of student profiles, number of participants, differentiated contents and schedules to achieve knowledge, outcomes and competences. Thus, a prototype application, named Learning Roadmap Studio (LRMS), has been developed and deployed at Aveiro Norte Polytechnic School of the University of Aveiro, in order to suppress gaps in learning processes and to power better learning and training. It represents a new challenge for the University of Aveiro for higher education and is already being tested. At its core is the concept of “learning roadmaps” that act upon two fundamental axes: education and learning. For the teachers, it aims at becoming a self-supporting tool that stimulates the organization and management of the course materials (lectures, presentations, multimedia content, and evaluation materials, amongst others). For the students, the learning roadmap aims at promoting self-study and supervised study, endowing the pupil with the capabilities to find the relevant information and to capture the concepts in the study materials. The outcome will be a stimulating learning process together with an organized management of those materials. It is not intended to create new learning management systems. Instead, it is presented as an application that enables the edition and creation of learning processes and strategies, giving primary relevance to teachers, instead of focusing on tools, features and contents

Representações sociais e agricultura familiar: indícios de práticas agrícolas sustentáveis no Vale do Bananal - Salinas, Minas Gerais.

A agricultura tem mostrado através dos tempos, responsabilidade histórica na transformação dos espaços naturais, proporcionada pela crescente necessidade de produção de alimentos. A intensa discussão dos problemas ambientais da atualidade tem exigido reflexão sobre a relação homem-natureza. O presente artigo, resultado de pesquisa de mestrado no Vale do Bananal, município de Salinas, Minas Gerais, do Programa de Pós-Graduação da Universidade Estadual de Santa Cruz, traz elementos da representação social do pequeno produtor rural, sobre meio ambiente e práticas agrícolas, mediante análise de seu discurso representado na coletividade e de sua prática agrícola de base familiar. Foi utilizada a teoria das Representações Sociais com a pesquisa de campo por meio da entrevista semi-estruturada e observação direta. A análise dos dados ocorreu através do Discurso do Sujeito Coletivo. Identificou-se vários problemas ambientais como desmatamento, uso de agrotóxicos, descaracterização da mata ciliar, erosão, contaminação de rio. Pode-se inferir que embora o pequeno produtor rural do Vale do Bananal no município de Salinas, possua uma percepção naturalista do meio ambiente, há indícios de práticas de uma agricultura sustentável

Long-term behaviour of railway transitions under dynamic loading application to soft soil sites

Dissertação para obtenção do Grau de Doutor em Engenharia CivilTransition zones in railway tracks are built to mitigate damage and wear to tracks and trains, and discomfort to passengers, caused by structural and foundation discontinuities, such as those introduced by bridge approaches or culverts. However, additional strains are still generated that cause changes of track geometry, that lead to more frequent maintenance operations and sometimes speed restrictions, that raise costs, and need to be minimized. This thesis addresses those questions and describes research undertaken to model the dynamic response of the railway tracks, taking into account the behaviour of ballast at the aforementioned railway transition zones, where the long-term settlements are amplified by dynamical loading on the ballast due to the discontinuities. Novel numerical models for the simulation of the dynamic response of the system soilballast-track-vehicle and accounting for those phenomena are presented. The models are validated by field measurements performed at a passage over a culvert, located in a soft soil site. The models include the unloaded level of the track, the possibility of voids under the sleepers, and the non-linear constitutive behaviour of the ballast, as well as representation, albeit simplified, of the vehicles. The forces transmitted to the ballast at transition areas vary considerably, both in time and space: loading of ballast reaches higher values than in regular tracks, and the additional vibrations cause larger differences between loads transmitted to consecutive sleepers. This causes higher densification of ballast at transition zones. Transition zones solely composed of approach slabs are not effective in soft soil sites. The soil and ballast at approach regions settle more than the segment on top of the much stiffer structure, leading to the appearance of hanging sleepers. The subsequent combined effect of lower load on part of the ballast and motion of the approach slabs results on increased settlement of the ballast and sub-ballast, increasing the voids under the sleepers, and causing more severe actions on the track. Possible improvement measures were modeled and tested computationally at the later stages of the thesis. The numerical simulations showed that the use of soft railpads on the stiff side of the transition is beneficial, provided the problem is mostly caused by stiffness variation of the track support. Slab track solution was also tested and showed advantages over the ballasted track by showing much smaller differential rail displacements,for identical change of the track support stiffness.Fundação para a Ciência e Tecnologia - Ph.D grant (SFRH/BD/25297/2005), through the project “Interacção solo-via férrea para comboios de alta velocidade” (POCI/ECM/61114/2004), and through the project SMARTRACK (PTDC/EME-PME/101419/2008

Equity research report on At&T - findind the value of a company within an overexploited sector

This report aims at depicting the past and future performance of both the Telecommunications and Media & Entertainment industries so that this analysis is embedded in determining AT&T’s intrinsic value by the end of 2021

Bereavement in older adults: individual challenge and contextual variables in different models

A perda por viuvez em idade avançada é, porventura, de entre vários acontecimentos do ciclo de vida, um dos mais normativos e, simultaneamente, dos menos investigados. Com o aumento da esperança de vida, a viuvez nos adultos idosos ocorre cada vez mais tarde no ciclo de vida, é um acontecimento expectável e parece haver vantagens em conceptualizá-lo como uma importante transição psico-social que implica a reconfiguração do significado da vida e dos seus propósitos. Neste artigo abordaremos alguns dos principais modelos do processo de luto e algumas variáveis individuais e contextuais que determinam reacções associadas à perda. Faremos uma particular focalização no modelo proposto por Stroebe e Schut bem como nas suas implicações teóricas e práticas.The loss of a spouse in old age is one of the most significant, but least investigated events in the life cycle. With increasing life expectancy, widowhood in older adults occurs increasingly later in the life cycle. It is an expectable event and may be advantageously conceptualized as a major psychosocial transition that involves the reconfiguration of the meaning of life and its purpose. The present article discusses some of the main models of the grieving process and the effect of some individual and contextual variables on reactions regarding the loss of a spouse. It focuses mainly on Stroebe and Schut dual process model as well as on its theoretical and practical implications

Roaming service for electric vehicle charging using blockchain-based digital identity

We present a suitable approach to address the electric vehicle charging roaming problem (e-roaming). Blockchain technologies are applied to support the identity management process of users charging their vehicles and to record energy transactions securely. At the same time, off-chain cloud-based storage is used to record the transaction details. A user wallet settled on a mobile application stores user verified credentials; a backend application in the vehicle charging station validates the user credentials to authorize the energy transaction. The current model can be applied to similar contexts where the user may be required to keep several credentials from different providers to authenticate digital transactions.info:eu-repo/semantics/publishedVersio

Tráfego rodoviário e ruído ambiental: o caso dum parque urbano

O ruído produzido pelo tráfego rodoviário é a primeira causa de poluição sonora em meio urbano. Em Portugal, e em consonância com as tendências dos restantes países da União Europeia, esta situação encontra-se regulamentada por intermédio da publicação de legislação específica. Tal vem obrigar à consideração do ruído urbano em fase de planeamento, nomeadamente na elaboração de planos de ordenamento do território. A determinação dos níveis de ruído é conseguida de uma forma vantajosa com recurso a modelos de previsão que, em função do conhecimento do tráfego e das características físicas do meio, permitem a avaliação de diversos cenários e a quantificação do clima acústico de modo contínuo no espaço. É apresentada a aplicação de um destes modelos a um espaço verde urbano, sendo calculadosmapas acústicos para os cenários de tráfego presente e futuro e proposta uma solução para mitigação do ruído.The noise produced by road traffic is the first cause of acoustic pollution an urban environment. In Portugal as well as in most of the European Union countries, this problem is regulated through the publication of specific legislation. These regulations require the consideration of the outdoor noise levels in the planning process, namely in the elaboration of zoning plans. The calculation of the noise levels is carried out using simulation models which, based on traffic data and site physical characteristics, allow the evaluation of scenarios and the quantification of such levels in a continuous space. In this paper a noise simulation model is applied to an urban recreation park. Acoustic maps are calculated for present and future traffic scenarios, and a mitigation solution is developed for the noise levels generated

THE ENERGETIC PERFORMANCE OF OLD BUILDINGS: HOW TO IMPROVE IT?

Along the years, in Portugal, the built environment was left behind and the straights were devoted for new buildings, creating new urban areas sometimes unattached from the existing city. The construction before the 80’s is compromised by its thermal quality if we consider that the thermal codes and the worry about thermal buildings behavior only came up around 90’s. In this work, the buildings from old city centers and its characteristics were studied as well as some intervention actions accurate for this construction and its results in terms of thermal performance. For this study a simulation tool was used, namely the Design Builder, and the results of these simulations were presented in order to understand the improvement in its thermal behavior when compared with its original conditions. It is possible to improve considerably the interior comfort and buildings thermal behavior with respect by architectonic characteristics and keeping constructive solutions and material with interventions actions that are compatible with existing structures