Search

Relatório de estágio de mestrado em Ensino de Música, O presente relatório insere-se no âmbito do Estágio Profissional do Mestrado em Ensino de Música da Universidade do Minho. O projeto de intervenção pedagógica foi implementado numa instituição de ensino especializado em música com alunos do 2º ciclo do ensino básico. O projeto “Conceitos basilares da dedilhação nos primórdios da aprendizagem do piano” visou realizar um estudo relativamente à eficiência do uso de uma dedilhação correta no ensino especializado de piano, direcionado para a fase inicial da aprendizagem. Embora as dedilhações sejam consideradas uma das componentes mais importantes da formação integral de um pianista, essas mesmas são frequentemente postas de lado no início da aprendizagem musical, apoiando-se na premissa de que este é um tema demasiado complexo de explicar a alunos mais imaturos. Tendo este facto em consideração, este projeto partiu da premissa de que a sua abordagem precoce poderá fazer a diferença na otimização do seu desempenho. Deste modo, o estágio teve como principal objetivo avaliar qual a melhor forma de abordar o tema das dedilhações, de maneira a promover o conforto da mão, a velocidade de execução, a independência na escolha das dedilhações e o desenvolvimento de uma melhor técnica pianística. Foi utilizada uma metodologia de investigação-ação, possibilitando de uma forma adequada a observação, planificação e preparação dos materiais a desenvolver na investigação. Apesar do curto espaço de tempo em que a intervenção se realizou, a análise dos dados obtidos indica que houve um acréscimo intelectual na aprendizagem dos alunos, que conseguiram adquirir uma maior variedade de conhecimentos relativos à técnica pianística., The presented internship report is part of the Professional Internship of the Masters in Musical Teaching at the University of Minho. The pedagogical intervention project was implemented in an educational institution specialized in music with students from the 2nd cycle of basic education. The “Basic concepts of fingering in the early stages of piano learning” project aimed to carry out a study regarding the efficiency of using correct fingering in specialized piano teaching, aimed at the initial phase of learning. Although fingerings are considered to be one of the most important components of the integral training of a pianist, they are sometimes set aside at the beginning of musical learning. Typically, instrument teachers rely on the premise that it is a theme too complex to explain to lesser mature students, which can make a difference in optimizing their performance. This way, the internship had as main objective the evaluation of the best way to approach the theme of fingerings, in order to promote hand comfort, speed of execution, independence in the choice of fingerings and also to develop a better piano technique. An action-research methodology was used, making it possible to properly observe, plan and prepare the materials to be developed in the investigation. The obtained data indicates that there is an intellectual increase in the student’s learning, since they were able to acquire a great variety of fingering knowledge (despite the short time span of the intervention).

Humans and most animals are able to navigate in their environment, which generates sensorial information of various kinds, such as proprioceptive cues and optic flow. Previous research focusing on the visual effects of walking (bob, sway, and lunge head motion) has shown that the perception of forward self-motion experienced by static observers can be modulated by adding simulated viewpoint oscillations to the radial flow. In three experimental studies, we examined the effects of several viewpoint oscillation frequencies on static observers' perception of the distance traveled, assuming the assessment of distance traveled to be part of the path integration process. Experiment 1 showed that observers' estimates depended on the frequency of the viewpoint oscillations. In Experiment 2, increasing the viewpoint oscillation frequency actually led to an increase in the global retinal flow. It also emerged that simulated viewpoint oscillations enhance the sensation of self-motion: In a specific low-frequency range (4 Hz), they improved subjects' estimates of the distances traveled. Lastly, in Experiment 3, observers were presented with two different simulated viewpoint oscillation patterns, both involving the same amount of global retinal motion, but in one case, the pattern simulated the visual effects of natural walking, and in the other case, the pattern was not biologically realistic. Contrary to the predictions of a previous ecological hypothesis, the subjects gave similar responses under both conditions. The global retinal motion may be mainly responsible for these effects, which were found to be optimal in a specific fairly low-oscillation frequency range.

Neurological disorders are a major concern in modern societies, with increasing prevalence mainly related with the higher life expectancy. Most of the current available therapeutic options can only control and ameliorate the patients’ symptoms, often be-coming refractory over time. Therapeutic breakthroughs and advances have been hampered by the lack of accurate central nervous system (CNS) models. The develop-ment of these models allows the study of the disease onset/progression mechanisms and the preclinical evaluation of novel therapeutics. This has traditionally relied on genetically engineered animal models that often diverge considerably from the human phenotype (developmentally, anatomically and physiologically) and 2D in vitro cell models, which fail to recapitulate the characteristics of the target tissue (cell-cell and cell-matrix interactions, cell polarity). The in vitro recapitulation of CNS phenotypic and functional features requires the implementation of advanced culture strategies that enable to mimic the in vivo struc-tural and molecular complexity. Models based on differentiation of human neural stem cells (hNSC) in 3D cultures have great potential as complementary tools in preclinical research, bridging the gap between human clinical studies and animal models. This thesis aimed at the development of novel human 3D in vitro CNS models by integrat-ing agitation-based culture systems and a wide array of characterization tools. Neural differentiation of hNSC as 3D neurospheres was explored in Chapter 2. Here, it was demonstrated that human midbrain-derived neural progenitor cells from fetal origin (hmNPC) can generate complex tissue-like structures containing functional dopaminergic neurons, as well as astrocytes and oligodendrocytes. Chapter 3 focused on the development of cellular characterization assays for cell aggregates based on light-sheet fluorescence imaging systems, which resulted in increased spatial resolu-tion both for fixed samples or live imaging. The applicability of the developed human 3D cell model for preclinical research was explored in Chapter 4, evaluating the poten-tial of a viral vector candidate for gene therapy. The efficacy and safety of helper-dependent CAV-2 (hd-CAV-2) for gene delivery in human neurons was evaluated, demonstrating increased neuronal tropism, efficient transgene expression and minimal toxicity. The potential of human 3D in vitro CNS models to mimic brain functions was further addressed in Chapter 5. Exploring the use of 13C-labeled substrates and Nucle-ar Magnetic Resonance (NMR) spectroscopy tools, neural metabolic signatures were evaluated showing lineage-specific metabolic specialization and establishment of neu-ron-astrocytic shuttles upon differentiation. Chapter 6 focused on transferring the knowledge and strategies described in the previous chapters for the implementation of a scalable and robust process for the 3D differentiation of hNSC derived from human induced pluripotent stem cells (hiPSC). Here, software-controlled perfusion stirred-tank bioreactors were used as technological system to sustain cell aggregation and dif-ferentiation. The work developed in this thesis provides practical and versatile new in vitro ap-proaches to model the human brain. Furthermore, the culture strategies described herein can be further extended to other sources of neural phenotypes, including pa-tient-derived hiPSC. The combination of this 3D culture strategy with the implemented characterization methods represents a powerful complementary tool applicable in the drug discovery, toxicology and disease modeling.

We herein report an experimental study examining the potential positive effects of Virtual Reality (VR) feedback during an indoor bicycling exercise. Using a regular bike coupled to a VR system, we compared conditions of no VR feedback, VR feedback and VR feedback with the presence of a virtual coach, acting as a pacer. In VR feedback conditions, we observed a decreased level of perceived exertion and an increased level of enjoyment of physical activity, when compared to a regular exercise situation (no VR feedback). We also observed a shift in the subjects' attentional focus, from association (in the absence of VR feedback) to dissociation (in VR feedback conditions). Moreover, the presence of a virtual coach in the VR environment triggered a systematic regulation of the (virtual) displacement speed, whose relationship with perceived enjoyment and exertion require further work.

Many experimental approaches to the control of steering rely on the tangent point (TP) as major source of information. The TP is a good candidate to control self-motion. It corresponds to a singular and salient point in the subject's visual field, and its location depends on the road geometry, the direction of self-motion relative to the road and the position of the driver on the road. However, the particular status of the TP in the optical flow, as a local minimum of flow speed, has often been left aside. We therefore assume that the TP is actually an optimal location in the dynamic optical array to perceive a change in the trajectory curvature. In this study, we evaluated the ability of human observers to detect variations in their path curvature from optical flow patterns, as a function of their gaze direction in a virtual environment. We simulated curvilinear self-motion parallel to a ground plane. Using random-dot optic flow stimuli of brief duration and a two-alternative forced-choice adaptive procedure, we determined path curvature discrimination thresholds, as a function of gaze direction. The discrimination thresholds are minimal for a gaze directed toward a local minimum of optical flow speed. A model based on Weber fraction of the foveal velocities (ΔV/V) correctly predicts the relationship between experimental thresholds and local flow velocities. This model was also tested for an optical flow computation integrating larger circular areas in central vision. Averaging the flow over five degrees leads to an even better fit of the model to experimental thresholds. We also found that the minimal optical flow speed direction corresponds to a maximal sensitivity of the visual system, as predicted by our model. The spontaneous gazing strategies observed during driving might thus correspond to an optimal selection of relevant information in the optical flow field.

Dissertação apresentada para a obtenção do Grau de Mestre em Genética Molecular e Biomedicina, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia A terapia génica é uma área em grande desenvolvimento nos últimos anos. Prova disso é o número crescente de ensaios clínicos aprovados nesta área, sendo os vectores adenovirais recombinantes (rAdVs) os veículos de transferência génica mais utilizados. As células mais utilizadas para produção de rAdVs são as HEK293, no entanto, estas células podem comprometer seriamente a segurança do produto final, uma vez que pode ocorrer recombinação homóloga entre o genoma celular e o genoma viral, conduzindo à formação de rAdVs com capacidade replicativa (RCA). Neste trabalho analisou-se o potencial de duas novas linhas celulares, derivadas de amniócitos humanos, 1D9 e 1G3 para a produção de rAdVs. Estas linhas celulares foram desenvolvidas de modo a não existirem sequências de homologia entre o genoma celular e viral, impossibilitando a formação de RCAs. A sua capacidade de produção de rAdVs foi avaliada comparativamente à da linha celular HEK293, em sistema estático e agitado, sendo realizada a caracterização metabólica das células durante o crescimento celular e infecção. Os valores de pO2 e pH do meio de cultura foram monitorizados, em sistema agitado, com precisão e não invasivamente, permitindo identificar parâmetros críticos a ter em conta no aumento de escala. O efeito da concentração celular no momento da infecção (CCI) na produção de rAdVs foi avaliado em culturas agitadas. A utilização das células 1G3 permitiu a infecção a CCIs superiores, sem uma diminuição significativa na produtividade específica, obtendo-se produtividades volumétricas superiores às das células HEK293. Este trabalho permitiu identificar e definir factores importantes para a produção rAdVs utilizando células 1G3, em sistema agitado. Foram ainda realizados ensaios preliminares de transfecção transiente com sucesso nas células 1G3, o que poderá permitir a sua utilização para a manufacturação de outros bio-produtos para além dos rAdVs, aumentando a sua flexibilidade. Os resultados obtidos aqui constituem informação valiosa para o futuro desenvolvimento e optimização de um processo de produção em bioreactor de bio-produtos para terapia em humanos, utlizando células potencialmente mais seguras.

The aim of the present study was to search for a sensorimotor marker (i.e., visuopostural tuning) that could be correlated with the severity of motor impairments in children with autistic spectrum disorders. Given that autistic children were previously reported to be posturally hyporeactive to visually perceived environmental motion in comparison with normal control children (Gepner et al., 1995), we sought to determine whether children with Asperger syndrome (AS) would share the same postural hyporeactivity to visual motion. Three autistic children with mild to severe motor impairments, three AS children with soft motor signs, and nine normal control children were tested for overall postural instability and postural reactivity to environmental motion. Results indicate, first, that overall postural instability is significantly reduced in autistic children compared with both AS and normal children. Second, although postural oscillations in the fore-aft axis become more attuned to the oscillation frequency of an immersive dynamic visual display as visual speed is increased, in both control and AS subjects, this is not the case in autistic children. Despite the small number of subjects tested in this study, our data confirm the existence of a visuopostural detuning in autistic children. Third, they argue for a correlation between visuopostural tuning and severity of motor signs in children with autistic spectrum disorders. Finally, they suggest a differentiation between children with autism and children with AS with regard to postural reactivity to fast visual motion. Neurophysiological implications of these results are discussed. In particular, a visuocerebellar pathway deficit hypothesis in autism is proposed.