Bounds for Invariance Pressure

This paper provides an upper for the invariance pressure of control sets with nonempty interior and a lower bound for sets with finite volume. In the special case of the control set of a hyperbolic linear control system in R^{d} this yields an explicit formula. Further applications to linear control systems on Lie groups and to inner control sets are discussed.Comment: 16 page

Performance analysis of portuguese equity mutual funds: indexing vs active portfolio management

The present thesis was done with the objective of analyzing the portfolio management strategies followed by managers of Portuguese Equity Funds, using the PSI Geral as the benchmark. Thus, the quarter returns and compositions of portfolio were used. The market timing ability and the variables that may have influenced tracking error (vs. PSI Geral) were also analyzed. The main conclusion was that just 1 fund managed to put successfully into practice the active portfolio management, obtaining returns above PSI Geral. The same happened with passive portfolio management, where only 1 fund was able to replicate the benchmark. The other funds opted initially for active or passive strategy but, in the end of the period considered, their performances were below the benchmark, with negative excess returns, even unable to replicate the PSI Geral. It was concluded also that there are several variables that have impact on performance of these funds, and consequently the portfolio management strategy, chosen by manager. These variables are particularly the systematic risk of the fund (beta), the benchmark volatility, percentage of PSI Geral stocks held in portfolio, weight of the stocks in portfolio, number of stocks above of the concentration ratio and number of common stocks between funds and benchmark, above of the concentration ratio.A presente tese foi elaborada com o objectivo de analisar a estratégia de gestão de carteira seguida pelos gestores dos Fundos de Investimento de Acções Nacionais, usando o PSI Geral como mercado de referência. Assim, foram usados os retornos e as composições trimestrais de carteira. A capacidade de Market Timing, e as variáveis que podem ter influenciado o Tracking Error (vs. PSI Geral) também foram analisados. A principal conclusão foi que só um fundo gerido conseguiu com sucesso pôr em prática a gestão activa da carteira, obtendo retornos acima do PSI Geral. O mesmo se passou com a gestão passiva, onde um fundo conseguiu replicar o mercado de referência. Os outros fundos optaram inicialmente por uma gestão activa ou passiva mas no final do período considerado, o seu desempenho ficou abaixo do mercado de referência, com excesso de retornos negativos, nem conseguindo replicar o PSI Geral. Foi também concluído que existem várias variáveis que têm impacto no desempenho destes fundos e consequentemente a estratégia de gestão de carteira escolhida pelo gestor. Estas variáveis são nomeadamente o risco sistemático do fundo (beta), volatilidade do mercado de referência, a percentagem de acções do PSI Geral na carteira, o peso das acções na carteira, número de acções acima do índice de concentração e o número de acções comuns entre o fundo e o mercado de referência, acima do índice de concentração

A Study on the Use of Eye Tracking to Adapt Gameplay and Procedural Content Generation in First-Person Shooter Games

This paper studies the use of eye tracking in a First-Person Shooter (FPS) game as a~mechanism to: (1) control the attention of the player's avatar according to the attention deployed by the player, and (2) guide the gameplay and game's procedural content generation, accordingly. This results in a more natural use of eye tracking in comparison to a use in which the eye tracker directly substitutes control input devices, such as gamepads. The study was conducted on a custom endless runner FPS, Zombie Runner, using an affordable eye tracker. Evaluation sessions showed that the proposed use of eye tracking provides a more challenging and immersive experience to the player, when compared to its absence. However, a strong correlation between eye tracker calibration problems and player's overall experience was found. This means that eye tracking technology still needs to evolve but also means that once technology gets mature enough players are expected to benefit greatly from the inclusion of eye tracking in their gaming experience

Genetic engineering of human cell lines for the improvement of viral vector production for gene therapy

A terapia génica baseada em vetores virais toma partido dos mecanismos biológicos naturais para entregar genes terapêuticos e controlar a sua expressão nas células alvo do paciente. Vários produtos de terapia génica viral estão já no mercado, com cerca de metade destes utilizando vírus recombinantes da família Retroviridae. Estes são uma opção frequente devido à sua elevada capacidade de transporte de carga genética, elevada eficiência de transdução, integração estável de genoma em loci transcricionalmente ativos, quer as células estejam em divisão ou não e devido à expressão a longo termo do gene entregue. As previsões de receita no mercado de terapia génica viral até 2020 ultrapassam os 200 milhões de dólares, sem perspetivas de declínio pelo menos até 2026. No entanto, a produção de retrovírus recombinantes depara-se com vários desafios. A elevada produção de partículas não-infecciosas – aproximadamente 1 em cada 1000 partículas produzidas são infecciosas – e baixo rendimento das plataformas de produção, dois fatores que impõem custos de produção altos, são as barreiras mais difíceis de ultrapassar na transição clinico-mercado. Vias metabólicas recrutadas em produção de retrovírus recombinantes foram previamente identificadas. Neste trabalho, cinco genes-alvo foram alvo de estudo numa linha celular produtora de retrovírus recombinantes. A sua sobre-expressão foi realizada através de transdução com vetores lentivirais. Os cinco genes considerados – BCL2, GSR, HSPA5, PDIA e XBP1 – pertencem a vias envolvidas em anti-apoptose, metabolismo de glutationa e síntese proteica no retículo endoplasmático. As populações resultantes foram caracterizadas quanto a crescimento celular, produtividade viral, expressão dos componentes virais e dos genes metabólicos. Verificou-se um aumento de produtividade associada à sobre-expressão dos genes intervenientes na síntese proteica no retículo endoplasmático. Aumentos de 140% foram obtidos com o gene XBP1 – que está associado à resposta de proteínas mal conformacionadas. Aumentos mais modestos, na ordem dos 63% foram obtidos com o gene PDIA2 – que está associado à catálise de pontes dissulfureto. Por último, aumentos de 76% foram observados com HSPA5 – que está associado a um grande leque de processos envolvidos em síntese proteica no retículo endoplasmático. Não foram observados aumentos de produção com genes associados à anti-apoptose nem ao metabolismo de glutationa, nomeadamente BCL2 e GSR. Os resultados aqui obtidos demonstram que engenharia metabólica é uma estratégia valiosa para o melhoramento de produção de retrovírus recombinantes. Três dos cinco genes abordados levaram ao aumento de produção de retrovírus recombinantes, o que apoia a síntese proteica como um alvo valioso na resolução dos constrangimentos encontrados na produção de retrovírus recombinantes. Este trabalho contribui para o campo da terapia génica baseada em vetores virais. O conhecimento gerado neste trabalho é relevante para outros vetores virais e para engenharia metabólica de linhas celulares humanas.Gene therapy using viral vectors harnesses naturally occurring viral biological mechanisms to deliver therapeutic genes and control their expression in patient target cells. Several viral gene therapy products have already reached the market, with nearly half being based on recombinant viruses belonging to the Retroviridae family. These are a frequent option since they have large genetic payload capacity, high transduction efficiency, stable genome integration in transcriptionally active loci of dividing and non-dividing cells and sustained long-term expression of the delivered gene. Revenue predictions for viral gene therapy market in 2020 surpass 200 million US dollars, with no decline perspective until at least 2026. Yet, recombinant retroviral synthesis faces several challenges. High non-infective particle concentration – roughly 1 in every 1000 produced particles are infective – and low yields of current production platforms, both of which impose high production costs, present the hardest barriers to overcome in clinical to market transition. Previously, metabolic pathways recruited in recombinant retroviral production were identified. In this work, five target genes were overexpressed in a stable recombinant retrovirus producer cell line through lentiviral vector transduction with incremental target gene expression. The five considered genes – BCL2, GSR, HSPA5, PDIA and XBP1 – belong to pathways involved in anti-apoptosis, glutathione metabolism and endoplasmic reticulum protein synthesis. Resulting populations were characterized for cell growth, recombinant retrovirus productivity, viral components and metabolic gene expression. Increase in productivity was associated to overexpression of genes intervenient in endoplasmic reticulum protein synthesis. Increases of 140% were obtained with XBP1 gene – which is associated to unfolded protein response and thus, correct protein folding. More modest increases of 63% were attributed to PDIA2 gene – which is associated to disulfide bond catalysis. Lastly, increases of 73% can be observed with HSPA5 – which is associated to a wide range of protein synthesis processes within the endoplasmic reticulum. Improvements in productivity were not observed with anti-apoptotic nor glutathione associated genes, namely BCL2 and GSR. The results herein obtained demonstrate cell metabolic engineering as a valuable strategy to improve recombinant retroviral production. Three of the five targeted genes resulted in higher recombinant retroviral production supporting protein synthesis as powerful targets for debottlenecking recombinant retroviral production. This work contributes for the viral gene therapy field. The knowledge generated in this work is relevant to other viral vectors and for metabolic engineering of human derived cell lines

Equity research - Ryanair Holding PLC

Mestrado em FinançasEquity Research sobre a Ryanair Holdings PLC (RYA), elaborado segundo as recomendações do CFA Institute, que integra a avaliação minuciosa de toda a sua atividade, com o objetivo final de se perspetivar o valor intrínseco das suas ações a 31 de Dezembro de 2020. A estrutura orgânica do presente documento é dividida em duas partes distintas: uma primeira parte, onde se analisa e se apresenta a RYA e a indústria onde se insere e uma segunda parte, onde, considerando as informações da primeira parte, se projeta e se mensura o desenvolvimento da empresa nos próximos anos, recorrendo a modelos de avaliação como o dos Fluxos de Caixa Atualizados e o Valor Atual Ajustado (métodos absolutos) e ainda ao modelo dos Múltiplos comparáveis (método relativo). Todo o conteúdo deste projeto contempla informações passíveis de análise até dia 27 de Setembro de 2019. Com um preço-alvo de €10,95, no final de 2020, calculado através do modelo dos Fluxos de Caixa Atualizados, representando um potencial de valorização de 6,37% considerando o preço de €10,29, a 27 de Setembro de 2019, a nossa recomendação de investimento é MANTER, ou seja, não se considera a existência de razões fortes para a compra, nem de razões negativas para a venda. Seguindo as especificações do modelo de Valor Atual Ajustado, alcança-se um resultado idêntico que sustenta a mesma recomendação. Com um preço-alvo de €11,10, o que totaliza um potencial de valorização de 7,90%, o conselho de MANTER, preserva-se.As part of the Master's Final Work in Finance, and according to the recommendations of the CFA Institute, this project about Ryanair Holdings PLC (RYA), which integrates the scrupulous analysis of all its business activity, has been settled with the main purpose of knowing the intrinsic value of its shares, on the 31st December, 2020. The organic structure of this project is divided into two distinct parts. The first part where RYA is analyzed and also the industry in which the Company operates; the second part, in which, the information in the first part is considered and it is forecasted and measured the Company's growth, over the next few years, using valuation models as Discounted Cash Flows (DCF), Adjusted Present Value (absolute methods) and the Multiples Approach (relative method). All of the developments of this project include information until 27th September 2019. With a target price of €10.95 at the end of 2020, given the DCF Model, representing an upside potential of 6.37% over the price of €10.29, on 27th September 2019, our investment recommendation is HOLD, that is no strong reasons for buying or selling. Considering the main features of Adjusted Present Value Model, an identical result was reached that supports the same investment recommendation. With a target price of €11.10, which adds up to a 7.90% upside potential, the advice of HOLD is well-maintained.info:eu-repo/semantics/publishedVersio

Controllability of discrete-time linear systems on lie groups with finite semisimple center

In this paper we stated a condition for the controllability of discrete-time linear systems for the case when the Lie group has finite semisimple center and provided a example in the Lie group $SL_2(\mathbb{R})$

Control sets of discrete-time linear system on affine group

This paper is focused to describe the control sets of the linear system on the bidimensional affine group when is considered a specific case of the trajectories with empty interior. We stated the existence of infinitely many control sets and a unique chain control set as well

Coalitions of end-use customers in retail electricity markets: a real-world case study involving five schools for children

ABSTRACT: The key mechanisms for purchasing and selling electrical energy include electricity pools and bilateral contracts. This article is devoted to bilateral contracting, which is modeled as a negotiation process involving an iterative exchange of offers and counter-offers. It focuses on coalitions of end-use consumers and describes a case study involving five schools for children located in England. The schools decide to ally into a coalition to strengthen their bargaining positions and, hopefully, to obtain better tariffs. To this end, they rely on a coordinator agent, who is defined from the group of five schools, by selecting either the “most powerful” school or the “best negotiator” school. The coordinator takes decisions according to either a “majority” rule, a “consensus” rule, or an “unanimity” rule. The simulations are performed with an agent-based system, called MATREM (for Multi-agent TRading in Electricity Markets). Although preliminary, the results suggest that coalition formation and management is beneficial to end-use customers, since the price agreed in the new forward contracts is more favorable to these agents, particularly when the coordinator is the “best negotiator” agent and considers the “unanimity” decision rule.info:eu-repo/semantics/publishedVersio

Evidence of social deprivation on the spatial patterns of excess winter mortality

Objectives: The aims of this study are to identify the patterns of excess winter mortality (due to diseases of the circulatory system) and to analyse the association between the excess winter deaths (EWD) and socio-economic deprivation in Portugal. Methods: The number of EWD in 2002–2011 was estimated by comparing the number of deaths in winter months with the average number in non-winter months. The EWD ratio of each municipality was calculated by following the indirect standardization method and then compared with two deprivation indexes (socio-material and housing deprivation index) through ecological regression models. Results: This study found that: (1) the EWD ratio showed considerable asymmetry in its geography; (2) there are significant positive associations between the EWD ratio and both deprivation indexes; and (3) at the higher level of deprivation, housing conditions have a stronger association with EWD than socio-material conditions. Conclusions: The significant association between two deprivation dimensions (socio-material and housing deprivation) and EWDs suggests that EWD geographical pattern is influenced by deprivation.info:eu-repo/semantics/publishedVersio

Simple and linear bids in multi-agent daily electricity markets: a preliminary report

ABSTRACT: Variable generation (VG) has several unique characteristics compared to those of traditional thermal and hydro-power plants, notably significant fixed capital costs, but near-zero or zero variable production costs. Increasing the penetration of VG tend to reduce energy prices over time, increase the occurrence of zero or negatively priced periods, and reduce the cleared energy levels of existing plants. This paper presents an overview of an agent-based system, called MATREM, to simulate electricity markets. Special attention is devoted to a case study that aims at analyzing the behavior of a simulated day-ahead market in situations with increasing levels of wind generation, and also comparing market schedules and prices in situations involving either simple and linear bids.info:eu-repo/semantics/publishedVersio