Machine learning Gaussian short rate

Dissertação para obtenção do Grau de Doutor em Estatística e Gestão do Risco

Estudo para a implementação de um sitema de e/b-learning no Centro de Formação da RTP

Trabalho de Projeto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Gestão de Sistemas de e-­‐Learning

O treino da expressão oral, estratégias em E-learning

Trabalho de Projeto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Gestão de Sistemas de E‐learning

Differing phagocytic function of monocytes and neutrophils in Chagas' cardiopathy according to the presence or absence of congestive heart failure

We evaluated the in vitro phagocytic function and the production of microbicidal oxygen radicals by monocytes and neutrophils of 9 Chagas' heart disease subjects with heart failure and 9 without the syndrome in comparison with 11 healthy subjects, by assessing phagocytosis of Saccharomyces cerevisiae and NBT reduction by peripheral blood phagocytes. Phagocytic index of monocytes of chagasics without heart failure was significantly 6.7 and 10.6 times lower than those of controls and chagasics with the congestive syndrome, respectively, due to a lesser engagement in phagocytosis and to an inability of these cells to ingest particles. Neutrophils also show in chagasics without heart failure PI 11.2 and 19.8 times lower than that of controls and chagasics with heart failure, respectively. The percent of NBT reduction was normal and similar for the three groups. Balanced opposite effects of cardiovascular and immune disturbances may be acting in Chagas' disease subjects with heart failure paradoxically recovering the altered phagocytic function.

Haptic robot-environment interaction for self-supervised learning in ground mobility

Dissertação para obtenção do Grau de Mestre em Engenharia Eletrotécnica e de Computadores

The Evolution of Function in the Rab family of Small GTPases

Dissertation presented to obtain the PhD degree in Computational Biology.

Integração de um Modelo de Aprendizagem em Blended-Learning no Curso de Informática Educativa, do Instituto Superior de Ciências da Educação da Huíla

Trabalho de Projecto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Gestão de Sistema de E-learning

Undrestanding postoperative cognitive dysfunction: novel insights

ABSTRACT: Background: Sleep is integral to biological function and sleep disruption can result in both physiological and psychological dysfunction. The acute cognitive consequences of sleep loss has been an active field of recent investigation, evidence suggests that sleep disruption in critically ill older adults can result in acute decrements in cognitive functioning. Surgery activates the innate immune system, inducing neuroinflammatory changes that interfere with cognition. The fact that patients with sleep disorders have an increased likelihood of exhibiting postoperative delirium encourages us to investigate the contribution of perioperative SF to the neuroinflammatory and cognitive responses of surgery. Methods: The effects of 24h sleep fragmentation (SF) and surgery were explored on adult C57BL/6J male mice. SF procedure started at 7 am with the home-cages being placed on a large platform orbital shaker cycled every 120 seconds (30 sec on/90 sec off). This procedure lasted for 24h. Stabilized tibia fracture was performed either before or after the 24h SF procedure. Separate cohorts of mice were tested for systemic and hippocampal inflammation and cognition. Results: Twenty-four hours of SF induced non-hippocampal memory dysfunction and increase in systemic IL-6. SF and surgery caused hippocampal-dependent memory impairment, although memory impairment was not exacerbated by combining SF with surgery. One day after either SF or surgery there was a significant increase in IL6 mRNA and TNF-alpha mRNA. These increments were more pronounced when either pre or post operative SF was combined with surgery. Conclusions: We show that while SF and surgery can independently produce significant memory impairment, perioperative SF significantly increased hippocampal inflammation without further cognitive impairment. The dissociation between neuroinflammation and cognitive decline may relate to our use of a sole memory paradigm that does not capture other aspects of cognition, especially learning.

Personal Learning Environments – Um Ecossistema de Aprendizagem em e-Learning

Esta investigação tem como tema de estudo os ambientes pessoais de aprendizagem que se podem desenvolver em e-learning. Estes ambientes com características singulares, face ao atual estado de desenvolvimento tecnológico e social, têm sido designados na doutrina científica pela expressão anglo-saxónica Personal Learning Environments, da qual derivam os acrónimos PLE ou PLEs. Este estudo tem, como objetivo, compreender o papel dos PLEs na aprendizagem dos alunos da parte letiva do Mestrado em Gestão de Sistemas de e-Learning, da Faculdade de Ciências Sociais e Humanas da Universidade Nova de Lisboa, nos biénios que decorreram de 2010-2011 a 2012-2013. Estes alunos, ao longo da sua aprendizagem, utilizaram várias ferramentas e/ou serviços associados com as TIC e Web 2.0. Esta utilização permitiu aos alunos criarem um ecossistema de aprendizagem próprio. A metodologia de investigação utilizada teve em consideração sobretudo aspetos qualitativos. A estratégia utilizada para a recolha de informações foi o inquérito por questionário. As informações recolhidas foram sujeitas a tratamento estatístico descritivo, e posterior triangulação dos resultados de algumas das variáveis.Dos resultados obtidos, é possível concluir que os alunos do Mestrado criaram os seus próprios PLEs e que estes facilitaram as suas aprendizagens. Que a sua utilização conferiu vantagens aos alunos. Que os PLEs foram fundamentais para poderem desenvolver atividades colaborativas, e que criaram um ecossistema próprio, uma rede de troca de conhecimentos.

Molecular regulation of secondary gorwth: searching for SHORT-ROOT function in cork formation

The analysis of molecular regulators involved in controlling the maintenance and function of plant meristems has been the subject of many studies. Some master regulators of these processes have been identified in Arabidopsis benefiting from the array of tools available for genetic and molecular analysis in this model plant. However, aspects such as secondary growth that are more extensively observed in woody plants, have been less studied. Secondary growth is responsible for the enlargement of the plant stems and roots and results from the activity of the lateral (secondary) meristems, vascular cambium and cork cambium (phellogen), which produce two important renewable natural resources, wood and cork, respectively.(...)

English Language Learning Inside and Outside the Classroom in Portugal

This study investigates the way of learning the English language in Portugal. First-year students of the faculty of Social Sciences and Humanities of New University of Lisbon were selected as participants in the case study. As data collection tools a questionnaire and focus-groups were used. 115 students completed the designed questionnaire and after that 12 students were selected for the more detailed focus-group discussions. Results of the research show that most part of the students´ English knowledge is received from outside the classroom by means of movies, songs, computer games, the Internet, communication with friends and other sources. Also, the results show that motivation is very important in language learning process and motivated students acquire the language faster and easier.

Assembly and function of a protein cross-linking enzyme during bacterial spore morphogenesis

Sporulation in Bacillus subtilis culminates with the formation of a dormant endospore. The endospore (or spore) is one of the most resilient cell types known and can remain viable in the environment for extended periods of time. Contributing to the spore’s resistance and its ability to interact with and monitor its immediate environment is the coat, the outermost layer of B. subtilis spores. The coat is composed by over 70 different proteins, which are produced at different stages in sporulation and orderly assembled around the developing spore.(...)

Learning Activities with Semantic. Hypermedia in Higher Education

The increasing use of information and communication technologies (ICT) in diverse professional and personal contexts calls for new knowledge, and a set of abilities, competences and attitudes, for an active and participative citizenship. In this context it is acknowledged that universities have an important role innovating in the educational use of digital media to promote an inclusive digital literacy. The educational potential of digital technologies and resources has been recognized by both researchers and practitioners. Multiple pedagogical models and research approaches have already contributed to put in evidence the importance of adapting instructional and learning practices and processes to concrete contexts and educational goals. Still, academic and scientific communities believe further investments in ICT research is needed in higher education. This study focuses on educational models that may contribute to support digital technology uses, where these can have cognitive and educational relevance when compared to analogical technologies. A teaching and learning model, centered in the active role of the students in the exploration, production, presentation and discussion of interactive multimedia materials, was developed and applied using the internet and exploring emergent semantic hypermedia formats. The research approach focused on the definition of design principles for developing class activities that were applied in three different iterations in undergraduate courses from two institutions, namely the University of Texas at Austin, USA and the University of Lisbon, Portugal. The analysis of this study made possible to evaluate the potential and efficacy of the model proposed and the authoring tool chosen in the support of metacognitive skills and attitudes related to information structuring and management, storytelling and communication, using computers and the internet.

Learning facial-expression models with crowdsourcing

The computational power is increasing day by day. Despite that, there are some tasks that are still difficult or even impossible for a computer to perform. For example, while identifying a facial expression is easy for a human, for a computer it is an area in development. To tackle this and similar issues, crowdsourcing has grown as a way to use human computation in a large scale. Crowdsourcing is a novel approach to collect labels in a fast and cheap manner, by sourcing the labels from the crowds. However, these labels lack reliability since annotators are not guaranteed to have any expertise in the field. This fact has led to a new research area where we must create or adapt annotation models to handle these weaklylabeled data. Current techniques explore the annotators’ expertise and the task difficulty as variables that influences labels’ correction. Other specific aspects are also considered by noisy-labels analysis techniques. The main contribution of this thesis is the process to collect reliable crowdsourcing labels for a facial expressions dataset. This process consists in two steps: first, we design our crowdsourcing tasks to collect annotators labels; next, we infer the true label from the collected labels by applying state-of-art crowdsourcing algorithms. At the same time, a facial expression dataset is created, containing 40.000 images and respective labels. At the end, we publish the resulting dataset.