Privacy in next generation networks

In the modern society, communications and digital transactions are becoming the norm rather than the exception. As we allow networked computing devices into our every-day actions, we build a digital lifestyle where networks and devices enrich our interactions. However, as we move our information towards a connected digital environment, privacy becomes extremely important as most of our personal information can be found in the network. This is especially relevant as we design and adopt next generation networks that provide ubiquitous access to services and content, increasing the impact and pervasiveness of existing networks. The environments that provide widespread connectivity and services usually rely on network protocols that have few privacy considerations, compromising user privacy. The presented work focuses on the network aspects of privacy, considering how network protocols threaten user privacy, especially on next generation networks scenarios. We target the identifiers that are present in each network protocol and support its designed function. By studying how the network identifiers can compromise user privacy, we explore how these threats can stem from the identifier itself and from relationships established between several protocol identifiers. Following the study focused on identifiers, we show that privacy in the network can be explored along two dimensions: a vertical dimension that establishes privacy relationships across several layers and protocols, reaching the user, and a horizontal dimension that highlights the threats exposed by individual protocols, usually confined to a single layer. With these concepts, we outline an integrated perspective on privacy in the network, embracing both vertical and horizontal interactions of privacy. This approach enables the discussion of several mechanisms to address privacy threats on individual layers, leading to architectural instantiations focused on user privacy. We also show how the different dimensions of privacy can provide insight into the relationships that exist in a layered network stack, providing a potential path towards designing and implementing future privacy-aware network architectures.

Mitochondrial plasticity in pathophysiological conditions

Both skeletal and cardiac muscles daily burn tremendous amounts of ATP to meet the energy requirements for contraction. So, it is not surprising that the maintenance of mitochondrial morphology, number, distribution and functionality in striated muscle are important for muscle homeostasis. In these tissues mitochondria present the added dimension of two populations, the intermyofibrillar (IMF) and the subsarcolemmal (SS) mitochondria, being IMF the most abundant one. In the present thesis, the molecular mechanisms harboured in mitochondria of striated muscles were studied using animal models, to better comprehend the role of mitochondrial plasticity in several pathophysiological conditions such as aging, diabetes mellitus and bladder cancer. The comparative analysis of IMF and SS populations isolated from heart evidenced a higher respiratory chain activity of mitochondria interspersed in the contractile apparatus. The higher susceptible of SS respiratory chain complexes subunits to carbonylation, but not to nitration, seems to justify the lower respiratory chain activity observed in this mitochondrial population. Our results showed that in heart from aged mice there is an accumulation of dysfunctional mitochondria. The age-related decrease of oxidative phosphorylation activity seems to be justified, at least partially, by the increased proneness of mitochondrial proteins as OXPHOS subunits and MnSOD to oxidative modifications. Moreover, a sedentary lifestyle seems to worsen the functional consequences of aging in heart by increasing mitochondrial proteins susceptibility to nitration. In skeletal muscle from rats with type 1 diabetes mellitus induced by streptozotocin administration, we verified the accumulation of dysfunctional mitochondria due, at least in part, to the impairment of PQC system. Indeed, the decreased activity of AAA proteases was accompanied by the accumulation of oxidatively modified mitochondrial proteins with impact in respiratory chain activity. The diminishing of mitochondria activity also underlies cancer-induced muscle wasting. Indeed, using a rat model of chemically induced urothelial carcinoma we verified that the loss of gastrocnemius mass was related to mitochondrial dysfunction due to, at least partially, the down-regulation of PQC system involving the mitochondrial proteases paraplegin and Lon. PQC impairment resulted in the accumulation of oxidatively modified mitochondrial proteins. In overall, regardless the pathophysiological stimuli that promote mitochondrial alterations, there are similarities in the pattern of disease-related mitochondrial plasticity. The diminished capacity for ATP production in striated muscle seems to be due to increased oxidative damage of mitochondrial proteins, namely subunits of respiratory chain complexes, metabolic proteins and MnSOD. Our data highlighted, for the first time, the impact of mitochondrial PQC system impairment in the accumulation of oxidized proteins, exacerbating the dysfunction of this organelle in striated muscle in several pathophysiological conditions.

Infection mechanism of Diplodia corticola

Diplodia corticola is regarded as the most virulent fungus involved in cork oak decline, being able to infect not only Quercus species (mainly Q. suber and Q. ilex), but also grapevines (Vitis vinifera) and eucalypts (Eucalyptus sp.). This endophytic fungus is also a pathogen whose virulence usually manifests with the onset of plant stress. Considering that the infection normally culminates in host death, there is a growing ecologic and socio-economic concern about D. corticola propagation. The molecular mechanisms of infection are hitherto largely unknown. Accordingly, the aim of this study was to unveil potential virulence effectors implicated in D. corticola infection. This knowledge is fundamental to outline the molecular framework that permits the fungal invasion and proliferation in plant hosts, causing disease. Since the effectors deployed are mostly proteins, we adopted a proteomic approach. We performed in planta pathogenicity tests to select two D. corticola strains with distinct virulence degrees for our studies. Like other filamentous fungi D. corticola secretes protein at low concentrations in vitro in the presence of high levels of polysaccharides, two characteristics that hamper the fungal secretome analysis. Therefore, we first compared several methods of extracellular protein extraction to assess their performance and compatibility with 1D and 2D electrophoretic separation. TCA-Acetone and TCA-phenol protein precipitation were the most efficient methods and the former was adopted for further studies. The proteins were extracted and separated by 2D-PAGE, proteins were digested with trypsin and the resulting peptides were further analysed by MS/MS. Their identification was performed by de novo sequencing and/or MASCOT search. We were able to identify 80 extracellular and 162 intracellular proteins, a milestone for the Botryosphaeriaceae family that contains only one member with the proteome characterized. We also performed an extensive comparative 2D gel analysis to highlight the differentially expressed proteins during the host mimicry. Moreover, we compared the protein profiles of the two strains with different degrees of virulence. In short, we characterized for the first time the secretome and proteome of D. corticola. The obtained results contribute to the elucidation of some aspects of the biology of the fungus. The avirulent strain contains an assortment of proteins that facilitate the adaptation to diverse substrates and the identified proteins suggest that the fungus degrades the host tissues through Fenton reactions. On the other hand, the virulent strain seems to have adapted its secretome to the host characteristics. Furthermore, the results indicate that this strain metabolizes aminobutyric acid, a molecule that might be the triggering factor of the transition from a latent to a pathogenic state. Lastly, the secretome includes potential pathogenicity effectors, such as deuterolysin (peptidase M35) and cerato-platanin, proteins that might play an active role in the phytopathogenic lifestyle of the fungus. Overall, our results suggest that D. corticola has a hemibiotrophic lifestyle, switching from a biotrophic to a necrotrophic interaction after plant physiologic disturbances.This understanding is essential for further development of effective plant protection measures.

O papel do turismo desportivo no desenvolvimento sustentável das áreas costeiras

Atualmente, a rotina sedentária leva a que as pessoas procurem cada vez mais a prática da atividades diferentes, tais como a atividade desportiva, que se torna essencial como fuga a este estilo de vida. O turismo desportivo tem assim crescido nos últimos anos e, por isso, a oferta existente hoje em dia é bastante variada. No entanto, é necessário ter em atenção que o uso dos recursos naturais, muitas vezes na base destas atividades, não deve ser excessivo. Igualmente, a busca pelo desenvolvimento sustentável deve fazer parte dos planos de todos os intervenientes no desenvolvimento dos destinos turísticos. A presente dissertação foca-se num estudo exploratório, com análise qualitativa, com o objetivo de analisar a importância do turismo desportivo na região de Aveiro. Assim, pretende-se compreender se esta atividade pode contribuir para o desenvolvimento da região de Aveiro enquanto destino turístico, garantindo simultaneamente a sustentabilidade das áreas costeiras. Em concreto, esta investigação realizou-se através de um inquérito por entrevista a agentes de oferta de animação turística que oferecem atividades de turismo desportivo. A necessidade de colaboração com a comunidade local e de integração nesta, bem como a urgência de criar parcerias com empresas do mesmo sector, ou até de sectores diferentes, são dois dos pontos essenciais nesta área, que podem conduzir a um desenvolvimento do turismo desportivo nas áreas costeiras, em concreto na região de Aveiro, sem comprometimento da sustentabilidade local.

Desenvolvimento de um veículo para a prática de cicloturismo

Com uma Sociedade cada vez mais complexa e evolutiva, vários são os desafios a que somos postos à prova. Com isto, a população apesar das suas dependências e comodismos, tende a procurar novos meios de lazer que se envolvam com a natureza e com a prática desportiva. Deste modo, o Cicloturismo vai ao encontro destas práticas, tornando-se um mercado em evolução, cuja a aderência do número de pessoas tem vindo a crescer, sendo um tipo de turismo que acarreta resultados positivos, tais como um estilo de vida saudável, bem como a utilização de um meio de transporte de baixo custo e com uma pegada ecológica. Na mesma linha de pensamento, o presente documento aborda todo o processo de execução de um Quadriciclo. O objetivo geral do mesmo, incide em satisfazer as necessidades dos praticantes de cicloturismo e incentivar as pessoas para o uso da bicicleta como meio de transporte. Para tal, os participantes envolvidos foram utilizadores assíduos do uso da bicicleta, não só procurando-a para o lazer, mas sim para a prática do Cicloturismo. Assim, os utilizadores do veiculo projetado têm o privilégio de ter como painel de fundo das suas viagens, o coração da natureza, disfrutando do conforto e da segurança que este proporciona, e ainda como resultado das mesmas, um estilo de vida mais saudável. De forma sequencial e organizada, utilizando como base a Metodologia de Ulrich e Eppinger, são notáveis os passos que foram dados para obter o produto final. Para além dos fortes conceitos de conforto, estabilidade, engenharia e ergonomia, é primordial salientar toda a importância do Design, uma vez que influenciou a disposição do veículo de quatro rodas, do início ao fim.