A experiência de visita dirigida a múltiplas atrações: análise do comportamento espacial do turista e da sua satisfação

Esta investigação teve como objetivo central averiguar se o comportamento espaciotemporal do turista urbano influencia a sua satisfação com a experiência de visita multiatração. Apesar de a mobilidade ser uma condição sine qua non do turismo, e, por outro lado, a visita a múltiplas atrações o contexto habitual em que se desenvolve a experiência turística em contexto urbano, a investigação neste domínio tende a ignorar a dimensão espaciotemporal e multiatração dessa experiência. O modelo conceptual proposto visa a sistematização da análise do comportamento espaciotemporal do turista bem como o estudo da sua relação com a satisfação, enquanto satisfação global e satisfação com dimensões da experiência. A partir deste, foi definido o modelo da pesquisa que, modelizando a questão central em estudo, teve por base dois instrumentos principais: estudo de rastreamento através de equipamento GPS e inquérito por questionário, realizados junto de hóspedes de dez hotéis de Lisboa (n= 413). A análise dos dados assume, por sua vez, dupla natureza: espacial e estatística. Em termos de análise espacial, a metodologia SIG em que se baseou a concretização dos mapas foi executada tendo como suporte a solução ArcGIS for Desktop 10.1, permitindo gerar visualizações úteis do ponto de vista da questão em estudo. A análise estatística dos dados compreendeu métodos descritivos, exploratórios e inferenciais, tendo como principal instrumento de teste das hipóteses formuladas a modelação PLS-PM, complementada pela análise PLS-MGA, com recurso ao programa SmartPLS 2.0. Entre as várias relações significativas encontradas, a conclusão mais importante que se pode retirar da investigação empírica é que, de facto, o comportamento espaciotemporal do turista urbano influencia a sua satisfação com a experiência de visita multiatração, afigurando-se particularmente importante neste contexto, em termos científicos e empíricos, investigar a heterogeneidade subjacente à população em estudo.

Calculus of variations on time scales and applications to economics

We consider some problems of the calculus of variations on time scales. On the beginning our attention is paid on two inverse extremal problems on arbitrary time scales. Firstly, using the Euler-Lagrange equation and the strengthened Legendre condition, we derive a general form for a variation functional that attains a local minimum at a given point of the vector space. Furthermore, we prove a necessary condition for a dynamic integro-differential equation to be an Euler-Lagrange equation. New and interesting results for the discrete and quantum calculus are obtained as particular cases. Afterwards, we prove Euler-Lagrange type equations and transversality conditions for generalized infinite horizon problems. Next we investigate the composition of a certain scalar function with delta and nabla integrals of a vector valued field. Euler-Lagrange equations in integral form, transversality conditions, and necessary optimality conditions for isoperimetric problems, on an arbitrary time scale, are proved. In the end, two main issues of application of time scales in economic, with interesting results, are presented. In the former case we consider a firm that wants to program its production and investment policies to reach a given production rate and to maximize its future market competitiveness. The model which describes firm activities is studied in two different ways: using classical discretizations; and applying discrete versions of our result on time scales. In the end we compare the cost functional values obtained from those two approaches. The latter problem is more complex and relates to rate of inflation, p, and rate of unemployment, u, which inflict a social loss. Using known relations between p, u, and the expected rate of inflation π, we rewrite the social loss function as a function of π. We present this model in the time scale framework and find an optimal path π that minimizes the total social loss over a given time interval.

Communication between nodes for autonomic and distributed management

Over the last decade, the most widespread approaches for traditional management were based on the Simple Network Management Protocol (SNMP) or Common Management Information Protocol (CMIP). However, they both have several problems in terms of scalability, due to their centralization characteristics. Although the distributed management approaches exhibit better performance in terms of scalability, they still underperform regarding communication costs, autonomy, extensibility, exibility, robustness, and cooperation between network nodes. The cooperation between network nodes normally requires excessive overheads for synchronization and dissemination of management information in the network. For emerging dynamic and large-scale networking environments, as envisioned in Next Generation Networks (NGNs), exponential growth in the number of network devices and mobile communications and application demands is expected. Thus, a high degree of management automation is an important requirement, along with new mechanisms that promote it optimally and e ciently, taking into account the need for high cooperation between the nodes. Current approaches for self and autonomic management allow the network administrator to manage large areas, performing fast reaction and e ciently facing unexpected problems. The management functionalities should be delegated to a self-organized plane operating within the network, that decrease the network complexity and the control information ow, as opposed to centralized or external servers. This Thesis aims to propose and develop a communication framework for distributed network management which integrates a set of mechanisms for initial communication, exchange of management information, network (re) organization and data dissemination, attempting to meet the autonomic and distributed management requirements posed by NGNs. The mechanisms are lightweight and portable, and they can operate in di erent hardware architectures and include all the requirements to maintain the basis for an e cient communication between nodes in order to ensure autonomic network management. Moreover, those mechanisms were explored in diverse network conditions and events, such as device and link errors, di erent tra c/network loads and requirements. The results obtained through simulation and real experimentation show that the proposed mechanisms provide a lower convergence time, smaller overhead impact in the network, faster dissemination of management information, increase stability and quality of the nodes associations, and enable the support for e cient data information delivery in comparison to the base mechanisms analyzed. Finally, all mechanisms for communication between nodes proposed in this Thesis, that support and distribute the management information and network control functionalities, were devised and developed to operate in completely decentralized scenarios.

Advanced energy efficient coordinated multi-point transmission for OFDMA

The ever-growing energy consumption in mobile networks stimulated by the expected growth in data tra ffic has provided the impetus for mobile operators to refocus network design, planning and deployment towards reducing the cost per bit, whilst at the same time providing a signifi cant step towards reducing their operational expenditure. As a step towards incorporating cost-eff ective mobile system, 3GPP LTE-Advanced has adopted the coordinated multi-point (CoMP) transmission technique due to its ability to mitigate and manage inter-cell interference (ICI). Using CoMP the cell average and cell edge throughput are boosted. However, there is room for reducing energy consumption further by exploiting the inherent exibility of dynamic resource allocation protocols. To this end packet scheduler plays the central role in determining the overall performance of the 3GPP longterm evolution (LTE) based on packet-switching operation and provide a potential research playground for optimizing energy consumption in future networks. In this thesis we investigate the baseline performance for down link CoMP using traditional scheduling approaches, and subsequently go beyond and propose novel energy e fficient scheduling (EES) strategies that can achieve power-e fficient transmission to the UEs whilst enabling both system energy effi ciency gain and fairness improvement. However, ICI can still be prominent when multiple nodes use common resources with di fferent power levels inside the cell, as in the so called heterogeneous networks (Het- Net) environment. HetNets are comprised of two or more tiers of cells. The rst, or higher tier, is a traditional deployment of cell sites, often referred to in this context as macrocells. The lower tiers are termed small cells, and can appear as microcell, picocells or femtocells. The HetNet has attracted signiffi cant interest by key manufacturers as one of the enablers for high speed data at low cost. Research until now has revealed several key hurdles that must be overcome before HetNets can achieve their full potential: bottlenecks in the backhaul must be alleviated, as well as their seamless interworking with CoMP. In this thesis we explore exactly the latter hurdle, and present innovative ideas on advancing CoMP to work in synergy with HetNet deployment, complemented by a novel resource allocation policy for HetNet tighter interference management. As system level simulator has been used to analyze the proposed algorithm/protocols, and results have concluded that up to 20% energy gain can be observed.

Avaliação da gestão curricular da matemática : cursos profissionais III

No mundo do trabalho, designadamente na indústria, acentua-se o défice de competências matemáticas nos profissionais da indústria, particularmente a Modelação Matemática, facto que constitui uma preocupação crescente à escala mundial e, obviamente, do sistema educativo português e da comunidade matemática nacional. Este défice é justificado pela falta de formação dos professores em contexto industrial e, de acordo com a National Council of Teachers of Mathematics, pela incapacidade que muitos docentes têm em apresentar a Matemática aplicada a situações laborais. Face à relevância social, económica e política da problemática descrita, centrou-se o presente estudo na Avaliação da Gestão Curricular da Matemática nos Cursos Profissionais de nível III do ensino secundário em Portugal, com enfoque na Modelação Matemática que, segundo os referentes internacionais, é simultaneamente uma competência e uma metodologia de ensino promotora do desenvolvimento de competências matemáticas nos profissionais da indústria. No contexto da gestão do currículo da Matemática para os cursos profissionais de nível III em escolas secundárias portuguesas, desenvolveu-se o presente estudo para se responder à questão de investigação: Em que medida a gestão curricular da Matemática, instituída, intencional e implementada nos cursos profissionais de nível III contempla situações-problema, suscetíveis de promover o desenvolvimento de competências no aluno, relevantes para o seu desempenho profissional? Construiu-se um referencial de avaliação, centrado na dimensão ecológica, segundo o modelo teórico Enfoque Ontosemiótico, abarcando um conjunto de sub-dimensões sobre as quais foram definidos critérios e respetivos indicadores. De realçar, ainda, que o referencial, além de ter servido de instrumento de avaliação da gestão curricular da Matemática nos cursos profissionais de nível III do ensino secundário, serviu, também, como guia orientador no desenho das sete situações-problema de natureza de Modelação Matemática no estudo de funções. O enquadramento metodológico do presente estudo assentou no método Estudo de Caso. Para analisar o caso, selecionaram-se sete unidades integradas de análise, a saber: a gestão curricular da Matemática de cada um dos seis professores participantes e a gestão curricular da Matemática instituída pelos normativos oficiais (programa da componente de formação científica da disciplina de Matemática para os cursos profissionais). Para a análise dos dados empíricos, respeitantes à gestão instituída, recorreuse à análise de conteúdo e teve essencialmente como propósito avaliar em que medida as orientações curriculares, emanadas no Programa da componente de formação científica disciplina de Matemática para os cursos profissionais de nível III, estão em conformidade com os referenciais teóricos. Sequencialmente, a operacionalização da avaliação intencional consubstanciou-se nos planos das aulas cedidos previamente a cada observação. A análise de conteúdo, como técnica de tratamento dos dados empíricos, foi a forma de se aceder às intenções de cada professor participante no estudo. A observação de aulas sucedeu à avaliação do plano de aula, constituindo a forma de avaliar in loco a gestão curricular da Matemática implementada, permitindo avaliar a coerência das observações com as intenções expressas nas planificações. Os registos das observações foram concretizados sob a forma de notas de campo que incluem uma componente descritiva e outra reflexiva que se dirigem para a análise dos dados empíricos recolhidos. Em termos de resultados, a avaliação da gestão curricular instituída foi reveladora de que o postulado pelos referentes para o desenvolvimento de competências tem a sua representação nas orientações curriculares expressas no Programa da componente de formação científica da disciplina de Matemática para os cursos profissionais de nível III. Contrariamente, a gestão curricular da Matemática pelos professores participantes revelou-se muito condicionada ao cumprimento dos conteúdos propostos pelo programa da disciplina. Por conseguinte, a gestão curricular da Matemática por competências, enfatizada no Programa (gestão instituída), encontrou, neste estudo, pouca tradução na gestão curricular intencional e implementada dos professores participantes, na medida em que a mesma não refletiu uma articulação com a componente de formação técnica do curso, visando uma metodologia proactiva no desenho de situações-problema promotoras de desenvolver, nos alunos, competências profícuas para a sua profissão, nomeadamente a Modelação Matemática. De salientar, ainda, que uma percentagem muito significativa de situações-problema propostas pelos professores não são, no geral, pertinentes para os respetivos cursos, não sendo, neste sentido, promotoras do estabelecimento de ligação com a futura performance profissional dos alunos. Tal lacuna parece ter resultado da ausência de trabalho colaborativo entre os professores de Matemática e os restantes docentes que constituem a equipa formativa do curso, lacuna que dificulta a articulação e coordenação em prol de um ensino contextualizado, ou ainda pela ausência de formação contínua pelos professores, no âmbito de temáticas inerentes à gestão curricular a cursos profissionais.

Characterization of water-soluble organic matter from urban aerosols

Water-soluble organic matter (WSOM) from atmospheric particles comprises a complex array of molecular structures that play an important role on the physic-chemical properties of atmospheric particles and, therefore, are linked to several global-relevant atmospheric processes which impact the climate and public health. Due to the large variety of sources and formation processes, adequate knowledge on WSOM composition and its effects on the properties of atmospheric aerosol are still limited. Therefore, this thesis aims at providing new insights on the molecular composition of WSOM from fine atmospheric aerosols typical of an urban area (Aveiro, Portugal). In a first step, adsorption phenomena of semivolatile organic compounds on quartz fibre filters employed in the collection of atmospheric aerosols were assessed. Afterwards, atmospheric aerosol samples were collected during fifteen months, on a weekly basis. A mass balance of aerosol samples was performed in order to set the relative contribution of elemental carbon, WSOM and water-insoluble organic matter to the aerosol mass collected at the urban area of Aveiro, with a special focus on the assessment of the influence of different meteorological conditions. In order to assess the chemical complexity of the WSOM from urban aerosols, their structural characteristics were studied by means of Fourier transform infrared infrared - Attenuated Total Reflectance (FTIR-ATR) and solid-state cross polarization with magic angle spinning 13C nuclear magnetic resonance (CPMAS 13C NMR) spectroscopies, as well as their elemental composition. The structural characterization of aerosol WSOM samples collected in the urban area highlighted a highly complex mixture of functional groups. It was concluded that aliphatic and aromatic structures, hydroxyl groups and carboxyl groups are characteristic to all samples. The semi-quantitative assessment of the CPMAS 13C NMR data showed different distributions of the various functional groups between the aerosol samples collected at different seasons. Moreover, the presence of signals typical of lignin-derived structures in both CPMAS 13C NMR and FTIR-ATR spectra of the WSOM samples from the colder seasons, highlights the major contribution of biomass burning processes in domestic fireplaces, during low temperature conditions, into the bulk chemical properties of WSOM from urban aerosols. A comprehensive two-dimensional liquid chromatography (LC x LC) method, on-line coupled to a diode array, fluorescence, and evaporative light scattering detectors, was employed for resolving the chemical heterogeneity of the aerosol WSOM samples and, simultaneously, to map the hydrophobicity versus the molecular weight distribution of the samples. The LC x LC method employed a mixed-mode hydrophilic interaction column operating under aqueous reversed phase mode in the first dimension, and a size-exclusion column in the second dimension, which was found to be useful for separating the aerosol WSOM samples into various fractions with distinct molecular weight and hydrophobic features. The estimative of the average molecular weight (Mw) distribution of the urban aerosol WSOM samples ranged from 48 to 942 Da and from 45 to 1241 Da in terms of UV absorption and fluorescence detection, respectively. Findings suggest that smaller Mw group fractions seem to be related to a more hydrophobic nature.

Analysis of the organic matter associated to sea salt : definition of potential molecular markers based on the volatile composition and presence of glycosidic derivatives and polysaccharides

Sea salt is a natural product obtained from the evaporation of seawater in saltpans due to the combined effect of wind and sunlight. Nowadays, there is a growing interest for protection and re-valorisation of saltpans intrinsically associated to the quality of sea salt that can be evaluated by its physico-chemical properties. These man-made systems can be located in different geographical areas presenting different environmental surroundings. During the crystallization process, organic compounds coming from these surroundings can be incorporated into sea salt crystals, influencing their final composition. The organic matter associated to sea salt arises from three main sources: algae, surrounding bacterial community, and anthropogenic activity. Based on the hypothesis that sea salt contains associated organic compounds that can be used as markers of the product, including saltpans surrounding environment, the aim of this PhD thesis was to identify these compounds. With this purpose, this work comprised: 1) a deep characterisation of the volatile composition of sea salt by headspace solid phase microextraction combined with comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (HS-SPME/GCGC–ToFMS) methodology, in search of potential sea salt volatile markers; 2) the development of a methodology to isolate the polymeric material potentially present in sea salt, in amounts that allow its characterisation in terms of polysaccharides and protein; and 3) to explore the possible presence of triacylglycerides. The high chromatographic resolution and sensitivity of GC×GC–ToFMS enabled the separation and identification of a higher number of volatile compounds from sea salt, about three folds, compared to unidimentional chromatography (GC–qMS). The chromatographic contour plots obtained revealed the complexity of marine salt volatile composition and confirmed the relevance of GC×GC–ToFMS for this type of analysis. The structured bidimentional chromatographic profile arising from 1D volatility and 2D polarity was demonstrated, allowing more reliable identifications. Results obtained for analysis of salt from two locations in Aveiro and harvested over three years suggest the loss of volatile compounds along the time of storage of the salt. From Atlantic Ocean salts of seven different geographical origins, all produced in 2007, it was possible to identify a sub-set of ten compounds present in all salts, namely 6-methyl-5-hepten-2-one, 2,2,6-trimethylcyclohexanone, isophorone, ketoisophorone, β-ionone-5,6-epoxide, dihydroactinidiolide, 6,10,14-trimethyl-2-pentadecanone, 3-hydroxy-2,4,4-trimethylpentyl 2-methylpropanoate, 2,4,4-trimethylpentane-1,3-diyl bis(2-methylpropanoate), and 2-ethyl-1-hexanol. These ten compounds were considered potential volatile markers of sea salt. Seven of these compounds are carotenoid-derived compounds, and the other three may result from the integration of compounds from anthropogenic activity as metabolites of marine organisms. The present PhD work also allowed the isolation and characterisation, for the first time, of polymeric material from sea salt, using 16 Atlantic Ocean salts. A dialysis-based methodology was developed to isolate the polymeric material from sea salt in amounts that allowed its characterisation. The median content of polymeric material isolated from the 16 salts was 144 mg per kg of salt, e.g. 0.014% (w/w). Mid-infrared spectroscopy and thermogravimetry revealed the main occurrence of sulfated polysaccharides, as well as the presence of protein in the polymeric material from sea salt. Sea salt polysaccharides were found to be rich in uronic acid residues (21 mol%), glucose (18), galactose (16), and fucose (13). Sulfate content represented a median of 45 mol%, being the median content of sulfated polysaccharides 461 mg/g of polymeric material, which accounted for 66 mg/kg of dry salt. Glycosidic linkage composition indicates that the main sugar residues that could carry one or more sulfate groups were identified as fucose and galactose. This fact allowed to infer that the polysaccharides from sea salt arise mainly from algae, due to their abundance and composition. The amino acid profile of the polymeric material from the 16 Atlantic Ocean salts showed as main residues, as medians, alanine (25 mol%), leucine (14), and valine (14), which are hydrophobic, being the median protein content 35 mg/g, i.e. 4,9 mg per kg of dry salt. Beside the occurrence of hydrophobic volatile compounds in sea salt, hydrophobic non-volatile compounds were also detected. Triacylglycerides were obtained from sea salt by soxhlet extraction with n-hexane. Fatty acid composition revealed palmitic acid as the major residue (43 mol%), followed by stearic (13), linolenic (13), oleic (12), and linoleic (9). Sea salt triacylglycerides median content was 1.5 mg per kg of dry salt. Both protein and triacylglycerides seem to arise from macro and microalgae, phytoplankton and cyanobacteria, due to their abundance and composition. Despite the variability resulting from saltpans surrounding environment, this PhD thesis allowed the identification of a sea salt characteristic organic compounds profile based on volatile compounds, polysaccharides, protein, and triacylglycerides.

Ritmos biológicos, cronotipo e funções cognitivas : um estudo de campo

Os primeiros estudos onde se tentava avaliar os melhores horários para se lecionar de forma a se poderem otimizar os horários escolares são já muito antigos. O primeiro a estabelecer uma relação sistemática entre performance cognitiva, Cronobiologia e sono foi Kleitman, evidenciando uma paralelismo entre o ritmo circadiano da temperatura central e a altura do dia em que eram realizadas tarefas simples de repetição. Após este primeiro estudo, muitos outros se seguiram, contudo a maioria apenas encontrou ritmos em protocolos de rotina constante e dessincronização forçada desprovidos de validade ecológica. Acresce ainda o facto de neste tipo de estudos não haver uma manipulação sistemática do efeito do padrão individual de distribuição dos parâmetros circadianos no nictómero, designado na literatura como Cronotipo. Perante isto, o presente estudo pretende avaliar a influência do Cronotipo nos ritmos cognitivos, utilizando um protocolo de rotina normal (Ecológico), onde também se manipula o efeito fim-de-semana. Para testar as premissas supramencionadas, utilizou-se uma amostra de 16 alunos universitários, que numa primeira fase responderam ao questionário de Matutinidade e Vespertinidade de Horne&Östberg, para caracterização do Cronotipo, e posteriormente andaram 15-17 dias consecutivos com tempatilumis (actímetros) para análise de ritmos de temperatura e atividade, com iPads onde realizavam ao longo do dia várias tarefas cognitivas e com o Manual de Registo Diário, onde respondiam ao diário de sono e de atividade. A análise de dados denotou a inexistência de expressão de ritmos na maioria dos parâmetros cognitivos inviabilizando a verificação de diferenças significativas entre indivíduos matutinos e vespertinos nestes parâmetros. Esta ausência de visualização da expressão rítmica pode ser explicada pelo facto de os participantes não terem aderido da forma desejada e exigida, à realização das tarefas cognitivas, ou pelo facto de termos usado um protocolo de rotina normal, em detrimento dos protocolos de rotina constate e dessincronização forçada, não controlando assim algumas variáveis que influenciam o desempenho cognitivo, podendo estas mascarar ou mesmo eliminar o ritmo. Ainda assim e apesar destas contingências observaram-se ritmos circadianos nas variáveis de autoavaliação, mesmo com o paradigma ecológico. Verificou-se ainda um efeito da hora do dia em vários parâmetros de tarefas cognitivas e motoras medidas objetivamente, assim como uma diminuição da performance cognitiva nos vespertinos, comparativamente aos matutinos, na janela temporal das 6h às 12 horas, que coincide com a maior concentração de horas de aulas por dia na Universidade onde o estudo foi realizado. Outros estudos serão necessários para consolidar a influência do Cronotipo nos ritmos cognitivos, utilizando o protocolo de rotina normal para garantir a validade ecológica, salvaguardando uma participação mais ativa na execução das tarefas cognitivas por parte dos sujeitos em estudo.

Interação intercultural telecolaborativa em português língua não materna

No âmbito do tema Multimédia em Educação, optámos por analisar uma sequência pedagógica em Português Língua Não Materna, contextualizada em interações interculturais telecolaborativas, mediadas pela plataforma Adobe Connect Pro. Para o efeito, foram transcritas as gravações dessas interações, submetidas a análise de conteúdo com o software de abordagem qualitativa webQDA, tendo em conta as seguintes dimensões: (i) dimensão operacional das literacias digitais online; (ii) atitude perante as tecnologias online; (iii) negociação de sentido, (iii) enunciados não relacionados com o projeto; (iv) atividades reflexivas sobre a língua por parte dos aprendentes; (v) enunciados dos participantes falantes nativos em interação com os aprendentes. Após a análise e discussão de resultados, é possível afirmar que a realização de interações interculturais telecolaborativas contribui para a reformulação de conhecimentos (Lankshear e Knobel, 2006) em termos de: competência tecnológica e literacia online; perceção de como as limitações técnicas podem condicionar a realização de um projeto; tomada de consciência do desenvolvimento (e vantagens) de uma atitude 2.0; aprofundamento da competência na língua-alvo e do conhecimento de realidades culturais através da comunicação com falantes nativos. Ainda assim, reconhecemos a pertinência e urgência do desenvolvimento de um trabalho com acuidade na área da formação intercultural telecolaborativa quer no âmbito da formação de professores (inicial e contínua) quer com os alunos durante as aulas de língua.

The economic consequences of Portuguese State’s movement towards business sector

Over the last 36 years, the relationship with the Portuguese state-owned enterprises registered several dynamics: nationalizations, privatizations and corporatization of public services. However, until now the State Business Sector from a national accounts perspective was never analyzed. Based on data collected and compiled for the first time at Statistics Portugal, this PhD thesis aims to test, analyzing in eight dimensions, whether the weight of the State Business Sector increased and if it contributed positively to the Portuguese economy, from 2006 to 2010. In addition to this analysis, an overview of the economic theory of state intervention in the economy, the paradigm changes of public policy in the international context, the evolution of the Portuguese State Business Sector since 1974, accompanied with a business and national accounting perspective between 2006 and 2010, are also presented. The results allow us to conclude that, in general, the weight of the State Business Sector in the Portuguese economy increased and had a tendency of a positive contribution to its economic growth. The State Business Sector also contributed positively to the nominal labour productivity (although with a decreasing trend of contribution to growth over the period under review) and the profitability of the non-financial corporations sector (although impairing the overall ratio of this sector). Nonetheless, the State Business Sector contributed negatively to the fairness in compensation of employees (although with an improvement trend) and to the competitiveness of labour cost, investment and sectorial sustainability of the Portuguese economy (reinforced by a falling trend). The results also suggest that the State Business Sector had an economic behaviour closer to a welfare maximizing model than to a profit maximizing model. This distinct performance with respect to the institutional sector in which is included, highlights the need to study and reassess the relationship of the state with public corporations, in light of agency theory using micro-data. Lastly, contributions to improve the economic performance of the State Business Sector and future prospects of evolution are presented.

Interactions of cetaceans with Spanish and Portuguese fisheries in Atlantic waters : costs, benefits and implications for management

With the aim to provide new insights into operational cetacean-fishery interactions in Atlantic waters, this thesis assesses interactions of cetaceans with Spanish and Portuguese fishing vessels operating in Iberian and South West Atlantic waters. Different opportunistic research methodologies were applied, including an interview survey with fishers (mainly skippers) and onboard observations by fisheries observers and skippers, to describe different types of interactions and to identify potential hotspots for cetacean-fishery interactions and the cetacean species most involved, and to quantify the extent and the consequences of these interactions in terms of benefits and costs for cetaceans and fisheries. In addition, the suitability of different mitigation strategies was evaluated and discussed. The results of this work indicate that cetaceans interact frequently with Spanish and Portuguese fishing vessels, sometimes in a beneficial way (e.g. cetaceans indicate fish schools in purse seine fisheries), but mostly with negative consequences (depredation on catch, gear damage and cetacean bycatch). Significant economic loss and high bycatch rates are, however, only reported for certain fisheries and associated with particular cetacean species. In Galician fisheries, substantial economic loss was reported as a result of bottlenose dolphins damaging artisanal coastal gillnets, while high catch loss may arise from common dolphins scattering fish in purse seine fisheries. High cetacean bycatch mortality arises in trawl fisheries, mainly of common dolphin and particularly during trawling in water depths below 350 m, and in coastal set gillnet fisheries (mainly common and bottlenose dolphins). In large-scale bottom-set longline fisheries in South West Atlantic waters, sperm whales may significantly reduce catch rates through depredation on catch. The high diversity of cetacean-fishery interactions observed in the study area indicates that case-specific management strategies are needed to reduce negative impacts on fisheries and cetaceans. Acoustic deterrent devices (pingers) may be used to prevent small cetaceans from approaching and getting entangled in purse seines and set gillnets, although possible problems include cetacean habituation to the pinger sounds, as well as negative side effects on non-target cetaceans (habitat exclusion) and fisheries target species (reduced catch rates). For sardine and horse mackerel, target species of Iberian Atlantic fisheries, no aversive reaction to pinger sounds was detected during tank experiments conducted in the scope of this thesis. Bycatch in trawls may be reduced by the implementation of time/area restrictions of fishing activity. In addition, the avoidance of fishing areas with high cetacean abundance combined with the minimization of fishery-specific sound cues that possibly attract cetaceans, may also help to decrease interactions. In large-scale bottom-set longline fisheries, cetacean depredation on catch may be reduced by covering hooked fish with net sleeves ("umbrellas") provided that catch rates are not negatively affected by this gear modification. Trap fishing, as an alternative fishing method to bottom-set gillnetting and longlining, also has the potential to reduce cetacean bycatch and depredation, given that fish catch rates are similar to the rates obtained by bottom-set gillnets and longlines, whereas cetacean by-catch is unlikely. Economic incentives, such as the eco-certification of dolphin-safe fishing methods, should be promoted in order to create an additional source of income for fishers negatively affected by interactions with cetaceans, which, in turn, may also increase fishers’ willingness to accept and adopt mitigation measures. Although the opportunistic sampling methods applied in this work have certain restrictions concerning their reliability and precision, the results are consistent with previous studies in the same area. Moreover, they allow for the active participation of fishers that can provide important complementary ecological and technical knowledge required for cetacean management and conservation.

The player and video game interplay in the gameplay experience construct

Among the many discussions and studies related to video games, one of the most recurrent, widely debated and important relates to the experience of playing video games. The gameplay experience – as appropriated in this study – is the result of the interplay between two essential elements: a video game and a player. Existing studies have explored the resulting experience of video game playing from the perspective of the video game or the player, but none appear to equally balance both of these elements. The study presented here contributes to the ongoing debate with a gameplay experience model. The proposed model, which looks to equally balance the video game and the player elements, considers the gameplay experience to be both an interactive experience (related to the process of playing the video game) and an emotional experience (related to the outcome of playing the video game). The mutual influence of these two experiences during video game play ultimately defines the gameplay experience. To this gameplay experience contributes several dimensions, related to both the video game and player: the video game includes a mechanics, interface and narrative dimension; the player includes a motivations, expectations and background dimension. Also, the gameplay experience is initially defined by a gameplay situation, conditioned by an ambient in which gameplay takes place and a platform on which the video game is played. In order to initially validate the proposed model and attempt to show a relationship among the multiple model dimensions, a multi-case study was carried out using two different video games and player samples. In one study, results show significant correlations between multiple model dimensions, and evidence that video game related changes influence player motivations as well as player visual behavior. In specific player related analysis, results show that while players may be different in terms of background and expectations regarding the game, their motivation to play are not necessarily different, even if their performance in the game is weak. While further validation is necessary, this model not only contributes to the gameplay experience debate, but also demonstrates in a given context how player and video game dimensions evolve during video game play.

Biology, ecology, population dynamics and distribution of metals in Sepia officinalis on a typical estuarine coastal lagoon - Ria de Aveiro

The common cuttlefish, Sepia officinalis, is a necto-benthic cephalopod that can live in coastal ecosystems, with high influence of anthropogenic pressures and thus be vulnerable to exposure to various types of contaminants. The cuttlefish is a species of great importance to the local economy of Aveiro, considering the global data of catches of this species in the Ria de Aveiro. However, studies on this species in Ria de Aveiro are scarce, so the present study aims to fill this information gap about the cuttlefish in the Ria de Aveiro. The cuttlefish enters Ria de Aveiro in the spring and summer to reproduce, returning to deeper waters in the winter. In terms of abundance, the eastern and center regions of the lagoon, closer to the sea, showed the highest values of abundance, while the northern and southern regions of the main channel had the lowest abundance. This fact may be related to abiotic factors, as well as depth, salinity and temperature. In the most southern point of the Ria de Aveiro (Areão) no cuttlefish was caught. This site had the lowest values of salinity and depth. The cuttlefish has an allometric the females being heavier than males to mantle lengths greater than 82.4 mm. Males reach sexual maturity first than females. In Ria de Aveiro in a generation of parents was found. The cuttlefish, presents itself as opportunistic predators, consuming a wide variety of prey from different taxa. The diet was similar in different sampling locations observing significant differences for the seasons. S. officinalis was captured at 10 sites in the Ria de Aveiro with different anthropogenic sources of contamination. Thus, levels of metals analyzed were similar at all sampling sites, with the exception of a restricted area, Laranjo, which showed higher values. The cuttlefish has the ability to accumulate metals in your body. The levels of Fe, Zn, Cu, Cd, Pb and Hg found in the digestive gland and mantle reflect a differential accumulation of metals in the tissues. This accumulation is related to the type and function of tissue analyzed and the type of metal analysis (essential and non-essential). The metal concentrations in the digestive gland are higher than in the mantle, with the exception of mercury. This may be due to the high affinity of the mantle for the incorporation of methylmercury (MeHg), the most abundant form of mercury. The accumulation of metals can vary over a lifetime, depending on the metal. The concentrations of Zn, Cd and Hg increases throughout life, while Pb decreases and essential metals such as Fe and Cu remain constant. The data collected suggest that the cuttlefish (Sepia officinalis) can be used as a bioindicator of environmental contamination for some metals.

Um modelo de medição e gestão de desempenho para as universidades públicas

Nas últimas décadas as instituições de ensino superior têm sido alvo de uma pressão crescente para aumentar a sua eficiência e a sua eficácia. Fatores como a diversificação da oferta formativa, a massificação, o aumento da internacionalização, entre outros, conduziram a uma maior monitorização das instituições e, por sua vez, geraram o desenvolvimento de novos sistemas de informação. A constante solicitação de informação, quer pelo Estado, quer pelo mercado constitui a base para a definição do objetivo desta investigação: construir um modelo integrado de medição e gestão de desempenho para as universidades públicas e testá-lo no universo português. Para a construção conceptual deste modelo foi realizada uma revisão da literatura baseada em diferentes contextos: organizacional, europeu e nacional. Este modelo foi depois aplicado às universidades públicas portuguesas recorrendo a dados disponibilizados por entidades públicas, tendo em conta a área de educação e formação (CNAEF). Uma análise descritiva aos dados constituiu uma contribuição desta investigação para a prática, no sentido de que permitiu fornecer um conjunto de recomendações às universidades e às entidades oficiais responsáveis pela recolha de dados a nível nacional, relativamente aos sistemas de informação e processos de recolha de dados. O modelo proposto constitui a contribuição teórica desta investigação, no sentido de que integra, no mesmo modelo, as diferentes dimensões de desempenho, a visão dos diferentes stakeholders, quer no contexto do ensino, quer no da investigação, quer no da própria gestão da universidade. A vertente analítica deste modelo, representada pelas diferentes relações entre os grupos de indicadores, foi testada recorrendo à técnica de análise de equações estruturais baseada na variância (nomeadamente Partial Least Squares) em quatro áreas CNAEF. Os resultados demonstraram que o comportamento em termos de medição e gestão de desempenho difere consoante a CNAEF, identificando um maior ajustamento às áreas hard e evidenciando que as áreas soft necessitam de indicadores mais ajustados às suas especificidades.

Psycho-physio dynamics in violin-piano duo: a pianist's perspective

The case study looked at psychological and physiological responses to stress in musicians, comparing a newly formed and a consolidated violin-piano duo. The common element between these duos was the pianist. Using the psychological tests (STAI Y1 and Y2, K-MPAI, MMPI-2, ICAC), the immunoassay saliva test to measure cortisol (stress hormone) and non- invasive device VitalJacket® developed at the University of Aveiro, Portugal, participants were monitored under various performance conditions. Others quantitative and qualitative dataset were collected including a pianist’s personal diary (analyzed by psychiatrist), semi-structured interviews with members of long-terms chamber music duo and perceptual evaluations (listening test) of the performances by expert listeners. The variables included two performance venues (European university and secondary school), as well as well-known repertoire, recently known repertoire and newly known repertoire. The latter was given approximately one week before each recital. The psychological and physiological dataset were collected for a total of eight recitals – two series of four recitals each. The unexpected results show that state anxiety levels and stress of the pianist, who does not present an anxious profile, either in social or in musical terms, are always higher when playing with a well-known partner. Possible explanations may be due to the highest expectations for quality of performance and implications of mirror neurons (since the reactions are very different according to the partner). In other words, the “known” (i.e., the consolidated duo) can become “trapped” within a predetermined space, especially at the psychological level, while the “unknown” (the occasional duo) seems to be less involved and therefore more reassuring and exciting in positive terms. In addition, the preference of the expert audience is for the consolidated duo.