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- Recovery of valuable aromas from sardine cooking wastewaters by pervaporation with fractionated condensation: matrix effect and model validationPublication . Pereira, M. João; Pintado, Manuela; Brazinha, Carla; Crespo, JoãoDue to the lack of studies addressing the influence of real food matrices on integrated organophilic pervaporation/fractionated condensation processes, the present work analyses the impact of the real matrix of sardine cooking wastewaters on the fractionation of aromas. In a previous study, a thermodynamic/material balance model was developed to describe the integrated pervaporation—a fractionated condensation process of aroma recovery from model solutions that emulate seafood industry aqueous effluents, aiming to define the best conditions for off-flavour removal. This work assesses whether the previously developed mathematical model, validated only with model solutions, is also applicable in predicting the fractionation of aromas of different chemical families from real effluents (sardine cooking wastewaters), aiming for off-flavour removals. It was found that the food matrix does not influence substantial detrimental consequences on the model simulations, which validates and extends the applicability of the model.
- Qual o impacto da pandemia na imagem das marcas? Um estudo na geração MillennialsPublication . Baptista, Marta Alves de Sá Pires; Côrte-Real, Ana Filipa da Rocha de Castro eA pandemia Covid-19 trouxe mudanças significativas a nível comportamental, económico e social. Nesse sentido, o presente estudo procurou aprofundar esta temática, propondo-se responder às questões de investigação: “Qual o impacto da pandemia na imagem das marcas?” e “Quais as marcas que se destacaram, fruto da sua atuação, durante a pandemia?”. Como tal, foi feita, numa primeira fase, a revisão de literatura sobre o conceito de marca e o conceito de responsabilidade social corporativa e, posteriormente, recorreu¬se a um estudo baseado num continuum entre a metodologia qualitativa e quantitativa, de forma a podermos dar resposta de forma mais válida às questões de investigação. O estudo qualitativo foi baseado na realização de focus group, a partir dos quais juntamente com a revisão de literatura foi elaborado um questionário, permitindo a execução do estudo quantitativo e uma maior generalização de dados. Assim, avaliando os resultados, concluiu-se que as empresas devem adotar práticas que promovam o bem-estar dos seus funcionários, práticas que preservem o ambiente, devem também adotar uma comunicação totalmente transparente e honesta e investir no canal online e na presença constante nas redes. No mesmo contexto, concluiu-se que marcas relacionadas com serviços de entregas e supermercados viram a sua reputação aumentar fruto das políticas de responsabilidade social que adotaram, fruto da higienização das lojas pertencentes a estas marcas e fruto da presença constante nas redes sociais.
- The diversification benefits of investing in BitcoinPublication . Dias, José Manuel Barroso Martins Salgado; Faria, Gonçalo Manuel A. Pereira Oliveira deIn this dissertation we aim to study the diversification benefits of investing in Bitcoin in a context of a well-diversified, balanced portfolio constituted by bonds and stocks (classic 60% equity/40% bonds Traditional Portfolio). Based on historical data, we evaluate the impact of different (i) holding periods of the investment, (ii) rebalancing frequencies of the portfolio and (iii) range of bitcoin allocations, on the overall performance of a given portfolio. A rolling analysis was performed to capture the time-dependent dynamics between these assets. We conclude that, for the sample period under analysis, quarterly rebalanced bitcoin allocations between 0.5%-7.5% for a minimum holding period of 3 years have always been beneficial for the investor, regardless of the period in which the investment was made. Although past performance is no guarantee of future performance, we believe that the empirical conclusions presented in this dissertation have significant implications for institutional investors.
- The central banks’ approach to digital currencies : a literature reviewPublication . Ferreira, Helena Maria Cardoso; Faria, Gonçalo Manuel A. Pereira Oliveira deConsidering the growing relevance of digital currencies and the constant speculation regarding their future, this work aims to analyze the existing literature on the treatment given by central banks to digital currencies. Adopting the form of a systematic literature review, we focus on central bank digital currencies, debating their pros and cons, and elaborating on how they should be designed. We find that the pros seem to outcome the cons, and that there is a clear preference from the authors for a retail digital currency.
- Shared service centre experience : the social relation of the shared service centre employeesPublication . Moreira, Sílvia Cristina Soares; Lencastre, Paulo de Neville SepúlvedaThe aim of this master thesis is to analyze the social relationship of the Porto Excellence Centre employees who work in a shared service centre of COFCO, the leader of the agricultural and food industry in China, and one of the world's leading agri-product traders with global footprints. The research for this paper includes a literature review, an interview, an online survey and the personal experience of the author as an intern in the company where the analyses was made. The main results indicate that the work the employees of the Porto Excellence Office and the units they provide services do require for both parties to be in constant interaction. Moreover, it was also identified that the social relations between the employees of the Porto Excellence Office were formed in a remote working context due to the Covid-19 pandemic. Overall, the social relation between the employees of the Porto Excellence Office and the units they provide services to is manly professional and rarely personal. The shared service centre is fundamental for COFCO International operations.
- Mechanical properties of polymethyl methacrylate as denture base material: heat-polymerized vs. 3D-printed — systematic review and meta-analysis of in vitro studiesPublication . Lourinho, Cláudia; Salgado, Helena; Correia, André; Fonseca, PatríciaThe synergy between dentistry and informatics has allowed the emergence of new technologies, specifically 3D printing, which has led to the development of new materials. The aim of this research was to compare the mechanical properties of dental base resins for 3D printing with conventional ones. This systematic review was developed using the PRISMA guidelines, and the electronic literature search was performed with the PubMed/MEDLINE, Web of Science—MEDLINE and EMBASE databases, until 30 April 2022. Two researchers selected the studies independently, and thus eight articles were found eligible for analysis. A meta-analysis was developed to estimate flexural strength. The Cohen’s kappa corresponding to this review was 1.00, and the risk assessment was considered low for the included studies. The 3D printing resin presented lower values of flexural strength and hardness compared with the heat-cured resin. Regarding impact strength, a lower value was recorded for the heat-cured resin compared with the 3D printing resin. Three-dimensional printing resins are viable materials for making prosthetic bases but need further clinical research.
- Music festivals as promoters for socioeconomic development : the case of Bons Sons FestivalPublication . Teixeira, Maria João Carvalho; Coelho, Sandra Cristina Lima; Seixas, Carlos Eduardo Soares deOriginally, music festivals appeared with the purpose of celebrating regional culture by bringing communities together (Duffy, 2000). There was a shift, decades later, and commercial motives started prevailing over community orientation. Hence, bigger music festivals started to be hosted in bigger metropolis, due to their more adequate infrastructures. A growing stagnation of rural areas can also be seen since they are unable to stem the exodus from the interior to the coast. The rise of nostalgic tourism has brought, however, some hope to these regions. Music festivals started being considered as a possible strategy for rural revitalisation, not just for generating economic benefits but to regenerate communities. As such, in this context, several questions emerge: “Can music festivals revitalize and develop rural communities? If yes, how does it happen?” To give a thorough answer to these questions, this research focused on the case of BONS SONS music festival. Interviews with two locals and the artistic director of the festival were conducted, as a survey to local businesses of Tomar was applied, to identify which were the cultural, social, and economic benefits and costs. Two OLS regressions were also estimated to understand if an impact was seen on the business’s organisations, from staging this music festival. Hence, this research resorts to a strategy of data triangulation, since three different research methods were combined. Results seem to indicate that BONS SONS festival contributes positively to the local economy. Besides leveraging local businesses, especially in the accommodation and food service activities sector, it contributes to the implementation of other social projects throughout the year.