The role of Di-iron proteins in pathogen resistance

Dissertation presented to obtain the Ph.D. degree in BiochemistryReactive oxygen and nitrogen species (ROS and RNS) are produced by phagocytic cells of the human immune system to attack invading pathogens due to their ability to damage DNA and the metal centres of proteins. In order to survive inside the host, bacteria activate genes that encode detoxifier enzymes, like the Escherichia coli nitric oxide-reductase flavodiiron protein, also known as flavorubredoxin (FlRd), and repairing proteins, such as the E. coli YtfE di-iron protein involved in the recovery of damaged Fe-S centres. Using E. coli and Staphylococcus aureus, the work presented in this thesis aimed at unravelling: i) the role of E. coli FlRd in bacteria exposed to a combination of oxidative and nitrosative stresses, ii) the identification and characterisation of S. aureus YtfE homologue, iii) the study of E. coli YtfE mechanisms that allow the repair of damaged Fe-S clusters, and iv) the identification of proteins that interact with E. coli YtfE. To analyse the role of E. coli FlRd in cells submitted to both hydrogen peroxide and nitric oxide, the transcription and expression of norV was explored by means of β-galactosidase and immunoblotting assays, respectively. Under these conditions, it was observed that the norV transcription and expression were hindered. To identify if the lack of norV expression was related to its regulator, the NorR transcription factor, the gene was cloned and expressed, and the protein was purified and the binding of nitric oxide to NorR in the presence of hydrogen peroxide was studied. EPR experiments revealed that upon incubation of NorR with nitric oxide and hydrogen peroxide the oxidation promoted by H2O2 of the monoiron centre of NorR impairs the ligation of nitric oxide.(...

From an Ontology for Programming to a Type-Safe Template Language

The demand to develop more applications in a faster way has been increasing over the years. Even non-experienced developers are jumping into the market thanks to low-code platforms such as OutSystems. The main goal of the GOLEM project is the development of the next generation of lowcode software development, aiming to automate programming and make the OutSystems platform easier to use. This work is integrated into the GOLEM project and focuses 1) on designing an ontology that will be used to capture concepts from a user dialogue; 2) on formalizing a template language; and 3) producing a reference implementation for OSTRICH. The ontology conceptsmust be representative enough to allow the generation of an application. A domain-specific language (DSL) produced in the scope of the GOLEM project will analyse the captured concepts, generating a set of operations that incrementally build and modify the target application. Because some of those application components are common patterns, they can be preassembled into templates to be later re-used. OSTRICH, a type-safe template language for the OutSystems platform, allows for the definition and instantiation of type-safe templates while ensuring a clear separation between compile-time and runtime computations. We formalize this two-stage language, defining its syntax, type system and operational semantics. We also produce a reference implementation and introduce new features: parametric polymorphism and a simplified form of type dependency. Such features enable instantiating the top ten most-commonly used OutSystems templates, which are more than half of all template instantiations in the platform. These templates ease and fasten the development process, reducing the knowledge required to build OutSystems’ applications.A necessidade de desenvolver aplicações a um ritmo cada vez mais acelerado tem aumentado ao longo dos anos. Mesmo programadores sem experiência têm vindo a integrar o mercado de trabalho nesta área, graças a plataformas low-code como a OutSystems. O projeto GOLEM tem como objetivo o desenvolvimento da próxima geração de lowcode, visando automatizar a programação e facilitar o uso da plataforma OutSystems. O objetivo desta dissertação, parte do projeto GOLEM, é 1) desenvolver uma ontologia para captar conceitos de um diálogo com o utilizador; 2) formalizar uma linguagem de templates; e 3) desenvolver uma implementação referência para o OSTRICH. Os conceitos da ontologia devem ser suficientemente representativos de forma a permitir a criação de uma aplicação. Uma linguagem de domínio específico (DSL) criada no escopo do projeto GOLEM irá analisar os conceitos captados e gera um conjunto de operações que constroem e modificam a aplicação-alvo incrementalmente. Visto alguns desses componentes da aplicação corresponderem a padrões comuns, estes podem ser previamente agregados num template para que possam ser reutilizados posteriormente. OSTRICH, uma linguagem de templates com segurança de tipos da plataforma OutSystems, permite definir e instanciar templates que respeitam as restrições de tipos, garantindo uma separação clara entre computações que ocorram em tempo de compilação e de execução. Nós formalizamos esta linguagem de duas etapas, definindo a sua sintaxe, sistema de tipos, e semântica operacional. Também desenvolvemos uma implementação de referência e introduzimos novas funcionalidades: polimorfismo paramétrico, e uma forma simplificada de dependência entre tipos. Estas funcionalidades permitem instanciar os dez templates OutSystems mais usados, correspondendo a mais do que metade das instanciações de templates na plataforma. Estes templates facilitam e aceleram o processo de desenvolvimento, reduzindo o conhecimento necessário exigido ao programador para a construção de aplicações Outsystems

Modelling of a prosthetic hand featuring individual grip on each one of the five fingers

Com o apoio RAADRI.The aim of this work is to develop a prosthetic hand with individual grip functionality on each finger, reproducing the natural movement of the hand. After the preparation of sketches and creating a virtual model, the final model shows dimensions: 124,04 mm × 246,57 mm × 38 mm (palm-covered) and an estimated weight of 1 kg, with all components. Afterwards was executed the functioning simulation of the prosthetic hand, elaborated prehension experiments were made using a metal cylinder, a rubber ball and a wooden pencil, with the tool Motion Study from Solidworks. However in the tests with the pencil was difficult to reach equilibrium, tells us that the hand is not functional with width smaller objects, because they require a bigger finger precision. Was made the study of forces applied in links thinner in different prehensions using the Finite Element Method. This study concluded that the aluminum alloy 2024 T3 has enough resistance to the stresses incurred for the grasping. Finally, was made an estimate cost of production for a single working prototype prosthetic hand. The result was 1325€

Thoughtful Packaging: How Inner Motivations Can Influence the Purchase Intention for Green Packaged Cosmetics

Dissertation presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Marketing IntelligenceThe cosmetics market is developing at a rapid pace, increasing consumers' concerns for sustainability. This sustainability trend raises firms' awareness to refresh their product range with new eco-friendly product lines and invest in sustainable packaging. To this end, this research conducted with 253 cosmetics consumers aims to investigate how the intrinsic behavioral motivators impact customers' buying intentions regarding green packaging. The current study extends the existing literature of social theories already developed and thoroughly examined by paving the way in investigating the association between an individual's characteristics (e.g., self-esteem, self-identity, moral satisfaction, planet ownership, product ownership, purchase intention for eco-packaged cosmetics, and their willingness to pay. In other words, the current study seeks to understand the internal factors of the customer that encourage the purchase of green cosmetics by providing a first conceptual framework that combines these factors. The findings can aid in maximizing the efficacy of packaging in green cosmetics to fulfill customer practical and emotional expectations and encourage environmentally-friendly consumer choices

Utilização de transportadores coloidais submicrométricos como estratégia para promover a fagocitose e o tropismo para as vias endocíticas em macrófagos

Tese de mestrado, Microbiologia Clínica, Faculdade de Medicina, Universidade de Lisboa, 2010O Mycobacterium tuberculosis é o agente patogénico da Tuberculose. Uma das suas principais características está relacionada com a sua capacidade de sobrevivência no interior dos macrófagos. Muito embora a eficácia e tolerância dos fármacos disponíveis não esteja em questão, o desenvolvimento de resistências e a falta de selectividade para as células-alvo revela-se cada vez mais preocupante. A terapêutica actual prolonga-se por longos períodos de tempo e requer a administração contínua e repetida de doses elevadas de fármacos. Este facto, em conjunto com os efeitos tóxicos, relacionados sobretudo com a administração sistémica, contribui para a falta de adesão dos doentes à terapêutica. É urgente o desenvolvimento de novos fármacos ou o desenvolvimento de sistemas que permitam a libertação modificada dos mesmos. As nanopartículas lipídicas (nsLp) são formulações farmacêuticas com um elevado potencial para direccionar e manter a concentração farmacológica nos tecidos-alvo, reduzindo desta forma os efeitos sistémicos dos fármacos incorporados. Neste trabalho desenvolveu-se um sistema lipídico-coloidal (nsLp), como transportador da proteína LysB, uma proteína obtida por indução da sua expressão em E. coli recombinante (pMP302), que demonstrou ser eficaz na inibição do crescimento bacteriano de culturas de Mycobacterium smegmatis. A investigação realizada em culturas de Mycobacterium smegmatis e em macrófagos infectados com o mesmo agente bacteriano permitiram avaliar o efeito da incorporação da LysB em nanopartículas lipídicas, nomeadamente, na sua estrutura e actividade antimicrobiana. Os resultados obtidos demonstraram que o sistema nsLp_LysB é mais eficaz que a proteína na sua forma livre para a inibição do crescimento bacteriano de Mycobacterium smegmatis, o que pode estar relacionado com a internalização celular facilitada das partículas endocitáveis. O sistema nsLp_LysB funciona assim como um transportador eficaz da proteína para células fagocitárias. A utilização de proteínas fágicas com propriedades lipolíticas como agentes terapêuticos da Tuberculose revela-se uma hipótese interessante. No entanto é necessário garantir a vectorização destas biomoléculas à sua célula-alvo. A utilização das nsLp com este objectivo terapêutico revela-se uma inovação tecnológica de sucesso, uma vez que estas têm sido descritas como transportadores selectivos de fármacos para o tratamento de doenças pulmonares.The pathogen of tuberculosis is Mycobacterium tuberculosis. One of its main characteristics is related to the ability of survival within macrophages. Although the drugs currently available are relatively well tolerated and effective, the development of resistance and difficulty in reaching the target cells (alveolar macrophages) is increasingly worrying. The current treatment extends over long periods of time and requires the continuous and repeated administration of high doses of drugs. Furthermore, the toxic side effects related to the systemic administration also promote a non-adherence of patients to therapy. It is urgent to develop new drugs or to develop systems that allow the modified release of same. Lipid nanoparticles (nsLp) are one of the systems under development with a high potential to increase and maintain the local concentration of drugs in target tissues, thus reducing its systemic effects in the blended drugs. The aim of this work is the development of a lipid-colloidal (nsLp) as a carrier of a protein (LysB) that has proved being effective in inhibiting the growth of bacterial cultures of Mycobacterium smegmatis. Thus, testing is carried out in cultures of Mycobacterium smegmatis and in macrophages infected with the same bacterial agent in order to check whether the effect of the free protein remained with the application of the nsLp_LysB system. The results showed that the nsLp_LysB system is equally or more effective than the protein in its free form for the inhibition of bacterial growth of Mycobacterium smegmatis, which could be related with the easy cellular internalization of the endocytic particles. Therefore the nsLp_LysB system is a good carrier of this protein to phagocytic cells. The use of phagic proteins with lipolitic properties as therapeutic agents of tuberculosis appears to be an interesting hypothesis. However it is necessary to ensure the targeting of biomolecules to their target organ. The use of nsLp with this therapy appears to be a technological innovation of success, as these have been described as excellent carriers of drugs via inhalation for the treatment of lung diseases

LSTM Models to Support the Selective Antibiotic Treatment Strategy of Dairy Cows in the Dry Period

Dissertation presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced Analytics, specialization in Data ScienceUdder inflammation, known as mastitis, is the most significant disease of dairy cows worldwide, invoking substantial economic losses. The current common strategy to reduce this problem is the prophylactic administration of antibiotics treatment of cows during their dry period. Paradoxically, the indiscriminate use of antibiotics in animals and humans has been the leading cause of antimicrobial resistance, a concern in several public health organizations. In light of these assumptions, at the beginning of 2022, the European Union made it illegal to routinely administer antibiotics on farms, with Regulation 2019/6 of 11 December 2018. Considering this new scenario, the objective of this study was to produce a model that supports the decisions of veterinarians when administering antibiotics in the dry period of dairy cows. Deep learning models were used, namely LSTM layers that operate with dynamic features from milk recordings and a dense layer that uses static features. Two approaches were chosen to deal with this problem. The first is based on a binary classification model that considers the occurrence of mastitis within 60 days after calving. The second approach was a multiclass classification model based on veterinary expert judgment. In each approach, three models were implemented, a Vanilla LSTM, a Stacked LSTM, and a Stacked LSTM with a dense layer working in parallel. The best performances from binary and multiclass approaches were 65% and 84% accuracy, respectively. It was possible to conclude that the models of the multiclass classification approach had better performance than the other classification. The capture of long- and short-term dependencies in the LSTM models, especially with the combination of static features, obtained promising results, which will undoubtedly contribute to producing a machine learning system with a prompt and affordable response, allowing for a reduction in the administration of antibiotics in dairy cows to the strictly necessary

Developmental recovery after adoption: child and adoptive family’s characteristics

Clínicos e investigadores têm alertado para os efeitos problemáticos das experiências precoces adversas, nomeadamente a da institucionalização, no crescimento físico, no desenvolvimento cognitivo e sócio-emocional, bem como nas relações de apego da criança. Após a adoção, a recuperação nestes domínios parece ser evidente, observando-se uma curiosa heterogeneidade nos resultados desenvolvimentais. Este artigo de revisão apresenta uma sistematização de resultados de estudos que analisaram a influência das características da criança e da família adotiva naquela recuperação. Pesquisou-se nas principais bases de dados eletrônicas e foram identificados estudos originais, de revisão e capítulos de livros. Concluiu-se que um entendimento da recuperação exige a exploração dos fatores genéticos, das experiências pré-natais e pré-institucionalização, e das vivências de cuidados anteriores e posteriores à adoção.Clinicians and researchers have been warning about the harmful effects of a history marked by early adverse experiences in shelter institutions in child’s health, cognitive and socioemotional development as well as attachment. After adoption, the recovery in these domains seems to be clear and it is also observed a curious heterogeneity in developmental results. This paper review presents a summary of the main empirical fi ndings about the characteristics of the child and of the adoptive family involved in the recovery process. The search was done in the major electronic databases and original studies, review articles, and book chapters were identifi ed. It is concluded that the recovery requires the identifi cation of genetic, prenatal and pre-institutionalization factors, and also the care experiences before and after the adoptionFundação para a Ciência e a Tecnologia (FCT).PTDC/PSI-PCL/101506/2008; Fundação Bial – Bolsa 13/06

Entrepreneurial backgrounds, human capital and start-up success

We examine whether founders backgrounds influence new firm survival in the early years after start-up. We develop hypotheses linking founders back-grounds to pre-entry capabilities associated with entrepreneurial human capital, highlighting the cases of spin-offs and habitual entrepreneurs. The subject of unemployment-driven entrepreneurship is also explored. We find that specific human capital more frequently found in spin-off founders plays a key role in enhancing survival chances, while more general forms of human capital may help inexperienced entrepreneurs overcome the barrier posed by the critical early years after start-up