Browsing by Issue Date, starting with "2021-12-17"
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- O Impacto da literacia financeira na tomada de decisões de investimento no mercado de ações: uma revisão sistemática da literaturaPublication . Inácio, Luís André Montes; Coelho, Luís; Peixinho, RúbenEsta dissertação revê a literatura existente sobre o impacto da literacia financeira na tomada de decisões de investimento no mercado de ações, com o objetivo de identificar eventuais lacunas de investigação que representem oportunidades para investigação futura, nomeadamente, ao nível de doutoramento. A metodologia utilizada neste trabalho é a revisão sistemática da literatura, que permitiu identificar e discutir um conjunto de trabalhos relevantes sobre o tema. Os resultados sugerem que este tópico é objeto de estudo há relativamente pouco tempo, porém, já foi algo explorado sob diversas perspetivas. O ano de 2015 foi o ano com maior número de artigos publicados nesta área, verificando-se a partir daí a produção de um maior número de trabalhos comparativamente com o período pré 2015. Os resultados demonstram que a literacia financeira afeta de forma diversa a tomada de decisão no mercado de ações. Por exemplo, maiores níveis de literacia financeira levam a uma maior participação no mercado de ações e reduzem o impacto dos vieses psicológicos sobre a tomada de decisão. Por outro lado, a literacia financeira está também associada à correção de comportamentos dos indivíduos após incidentes no mercado. No entanto, o presente estudo mostra que existe ainda possibilidade de contribuir para este campo de literatura, nomeadamente no que concerne à relação entre a literacia financeira e diversificação do portfólio.
- DNA barcoding as a tool to explore elasmobranch diversity in environmental DNA off the Banc d´Arguin (Mauritania)Publication . Hoz Schilling, Carolina de la; Serrão, Ester; Jabado, Rima W.Sharks and rays are the most threatened group of marine vertebrates. Extinction risk is highest for species in tropical and subtropical areas, often associated with developing nations that generally lack baseline data on species diversity. Although considered a regional elasmbranch hotspot, species diversity in the Banc d’Arguin National Park (PNBA) in Mauritania has not been characterized. Here, a first description of species diversity is provided based on a combination of approaches. DNA barcoding was used to build a regional genetic reference database of species sampled at local processing and landing sites. Two potentially new species (genus Gymnura and Torpedo) were found and possible new lineages for Sphyrna lewini and Aetomylaeus bovinus were uncovered, however, results should be observed with caution and are pending further confirmation. Mustelus punctulatus and Hypanus rudis were confirmed from Mauritania for the first time, extending their known distribution range. Metabarcoding was used to explore species diversity in eDNA samples from the PNBA. Results confirmed the presence of 29 different species, 12 sharks and 17 rays of which 14 species had previously never been reported from the PNBA in the literature. Notably, Mustelus punctulatus was found in 77% of the eDNA samples, while the only locally reported smoothhound, M. mustelus, was absent in all samples. Sphyrna lewini, a species previously reported, was absent from all eDNA samples, however its presence was visually confirmed. Putative new Gymnura and Torpedo species were found throughout various eDNA samples. A total of 66.6% of shark and ray species in the PNBA are threatened with extinction (including S. lewini). Considering the high fishing pressure sharks and rays are exposed to, these results emphasize the importance of taxonomic identification for individual species management and provide a baseline to inform future studies and shark and ray specific conservation measures in the PNBA.
- A perceção do risco no corpo de Bombeiros Municipais de OlhãoPublication . Conceição, Soraia Viegas; Sequeira, Bernardete; Santos, BrunoO presente relatório surge na sequência do estágio curricular realizado no Corpo de Bombeiros Municipais de Olhão. Constituindo-se objeto de avaliação para a obtenção do grau de Mestre em Sociologia, integrante no último ano do respetivo mestrado da Faculdade de Economia da Universidade do Algarve, o presente documento tem como objetivo primordial relatar a experiência de estágio, em particular as funções e tarefas que integraram o plano de trabalho durante as 770 horas de estágio. As funções desempenhadas durante o estágio curricular centraram-se na lógica de atuação do Corpo de Bombeiros Municipais de Olhão, tendo participado em atividades relacionadas com a elaboração de relatórios ao nível da gestão operacional e integrado ações estratégicas focalizadas na gestão do risco ocupacional, particularmente no âmbito da prevenção de acidentes de trabalho. Para além do trabalho desenvolvido no âmbito do presente quadro de ação, a estagiária teve a oportunidade de integrar atividades no domínio da sensibilização ao nível da prevenção e segurança direcionadas para a população em geral com a elaboração do projeto A Proteção Civil Somos Todos Nós e a colaboração na iniciativa Seja responsável! Proteja-se a si e aos outros!. Com a finalidade de contribuir para um conhecimento mais detalhado daquelas que são as particularidades do exercício de funções como bombeiro, paralelamente às funções desempenhas no decorrer do estágio foi realizada uma investigação de âmbito sociológico. Assim, realizou-se um estudo de caso de caráter exploratório e descritivo que pretendeu aferir a perceção do risco dos elementos que integram o Corpo de Bombeiros Municipais de Olhão. A recolha dos dados foi efetuada a partir da pesquisa documental e da aplicação de um inquérito por questionário, tendo sido o tratamento estatístico elaborado com recurso ao software SPSS. Os resultados revelam que grande parte dos inquiridos da corporação em estudo consideram a atividade de bombeiro de risco extremamente elevado. Os resultados indicam também que a maioria dos inquiridos consideram que se encontram mais expostos a situações de risco biológico no decurso da sua atividade. Contudo, verifica-se que, de uma forma geral, são as situações de risco químico que mais preocupam os elementos inquiridos.
- Ideologia de género, centralidade da carreira e interação trabalho - famíliaPublication . Lopes, Adriana Beatriz Nunes Fachas; Gonçalves, GabrielaO propósito deste estudo é perceber com base na ideologia de género os efeitos da importância da carreira e da família na identidade do indivíduo, com o indicador do conflito trabalho-família. Este estudo está inteiramente ligado à ideologia de género que menciona que os homens estão encarregues do bem-estar económico da família e as mulheres são responsáveis pelas lides da casa e pelo zelar dos filhos. Nos últimos anos a estrutura da família tem sofrido várias alterações, estamos perante uma mudança ao nível da entrada das mulheres no mercado de trabalho, e também à substituição de um modelo família por um modelo de dupla carreira. As mulheres começaram as suas carreiras profissionais, e surgiu uma divisão de papéis entre o casal, e aqui inicia-se a articulação da vida profissional com a vida familiar (Wall, 2010). Esta mudança na vida das mulheres e dos homens originou dificuldades na gestão da vida profissional com a vida familiar.
- Nanoplastic neurotoxicity in the Marine Mussel Mytilus galloprovincialisPublication . Acker, Rachel; Bebianno, Maria João; Fonseca, Tainá Garcia daPlastic is a ubiquitous, long-lasting, problematic form of litter. It has been found everywhere on Earth, from the bottom of the ocean’s deepest trench to the top of the world’s tallest mountain. As the COVID-19 pandemic rages on, so does the global dependence on the usage of single use plastics (SUPs), such as disposable face masks and takeout food containers. Once released into the environment, plastic fragments break down into microplastics (1-5 mm) and nanoplastics (1-100 nm) due to fragmentation and degradation processes. Compared to microplastics, nanoplastics have a much larger surface area to volume ratio, which makes them more reactive since they can adsorb different chemicals and travel across biological barriers. The present research was conducted to unravel potential toxicity responses caused by nanoplastics. This suggests that the seeping of plastics through cell membranes can affect all organisms, including those in higher trophic levels that consume contaminated prey. Toxins caused by nanoplastics may travel up the food chain and pose a risk to human health. This study confirmed neurotoxic effects in the gills of marine mussels Mytilus galloprovincialis after an exposure of 10 μgL-1 of Polystyrene (PS) nanoplastics after 21 days of contamination followed by 14 days of depuration using the biomarker Acetylcholinesterase (AChE).
- Gravading of mackerel (Scomber sp.): physicochemical and sensory changes during refrigerated storagePublication . Adetokunbo, Mujeeb Adewale; Esteves, E.; Aníbal, J.The Atlantic Mackerel (Scomber colias) is a fast-swimming pelagic fish that can be found in the warm, temperate waters of the Atlantic Ocean, as well as on the shelf and upper slopes of the Mediterranean Sea. Mackerel is a great source of long-chain n-3 polyunsaturated fatty acids, compounds that have health benefits. Mackerel is also a good source of proteins, essential amino acids and other biologically active compounds. However, it is highly vulnerable to lipid oxidation due to the large amount of unsaturated fatty acids it contains. Gravading is a fish processing technique popular in Scandinavian and Nordic countries, which involves applying a mixture of salt and sugar to the fish fillets and then letting it mature for 1-4 days at low temperature (in refrigeration) to produce gravads, a salt-sugar delicacy with a salt content of 3 –6% and a pH greater than 5. This process has been applied to fish such as salmon, whitefish, trout, or Greenland sole. The main objective of this work was to study the effect of the gravading process on mackerel fillets using physicochemical, biochemical and microbiological parameters. Specifically, it was intended to study the effect on the quality and storage stability of mackerel that went through the gravading process; monitor some quality parameters, namely color (CIE Lab), texture (hardness), pH, water activity and moisture content, total volatile basic nitrogen content (TVB-N), or thiobarbituric acid reactive substances content (TBARS) and the presence/abundance of microorganisms evaluating total aerobic and psychotropic bacteria counts; and to study and understand how two different storage temperatures, 4 °C and 9 °C, can influence changes in these quality parameters. Experimental and laboratory work took place from early April to mid-July 2021 at the Chemical and Food Processing Laboratories of the Department of Food Engineering of the Institute of Engineering (ISE) of the University of Algarve (UAlg), Campus da Penha, Faro, Portugal. The fish, S. colias, were purchased from the Municipal Market of Faro, frozen on that date in an air-blast freezer under appropriate conditions (-25°C) and stored frozen (-18°C) until the beginning of the trial, in May 2021. The quality parameters were evaluated for samples (n=3) of fresh fillets on the first day of sampling, before application of the application of the gravad mix, and after 48 h of gravading, the other fillets subjected to gravading were vacuum packed and divided into two groups, one set of packages was stored refrigerated at 4 °C and the other at 9 °C. The same parameters were evaluated in fillets (n=3) of each storage condition, once a week until 4 weeks of storage, after which sampling was done once every two weeks until the 10th week of sampling, in July 2021. The color parameters did not show a particular trend throughout the test, except in the case of L* luminosity, which decreased with time, probably due to the dehydration process. On the other hand, the water activity decreased to about 0.80, a level at which only yeasts and molds and halophyte bacteria can survive, contributing decisively to the stability of the product. The texture of mackerel underwent major changes due to gravading, as excess of sugar and salt increases the osmotic pressure and contributes to the removal of water from fish tissue. This caused the hardness to increase until the fourth week of storage, after which it starts to decrease. Generally speaking, quality parameters did not change with temperature, but all seem to deteriorate after four weeks. In fact, the TVB-N content gradually increased after the fourth week. TBARS values also increased during this period. The total aerobic and psychotropic bacteria counts were around 4 log(UFC/g) which is the common level for other fish species subject to gravading and well below 6 or 7 log(UFC/g), which is considered the critical level for microbiological contamination. This shows a high quality of raw material and product. The fillets subjected to gravading, vacuum-packing and kept in refrigeration, regardless of storage temperature, appear to lose quality after four weeks, a shelf-life that can be partly credited to the vacuum packaging that inhibits the survival and growth of microorganisms.
- Storytelling in heritage tourism: an exploration of co-creative experiences from a tourist perspectivePublication . Beevor, Meghan Claire; Guerreiro, Manuela; Campos, Ana CláudiaHeritage attractions and museums are under pressure to adapt to the needs of experience-seeking tourists. If they are to remain competitive, managers must acknowledge the visitor’s role as a co-creator and facilitate heritage experiences that privilege co-creation between the experience provider and consumer. Storytelling has been posited as a co-creative tool that increases consumer engagement and leads to memorable tourist experiences. As such, storytelling presents itself as an accessible and effective way to offer experiences that are more aligned with the expectations of the modern heritage tourist. However, a lack of knowledge exists regarding storytelling’s definition, implementation, and impact in heritage tourism settings. This work addresses these problems by identifying the various elements of heritage storytelling, providing a practical example of how these elements can be implemented in a real service context, and evaluating the impact of storytelling on visitors. Based on a review of the literature, the author created an experimental methodological framework that breaks down heritage storytelling into its various elements. Using this framework, a “storytelling tour” was designed and implemented at the Islamic Museum of Tavira. This tour was then tested on three groups of participants, who then participated in focus groups to share their thoughts on the storytelling experience. Focus group data was analyzed using reflexive thematic analysis in NVivo. Data analysis revealed that, overall, participants received the “storytelling tour” positively. Regarding storytelling’s impact on the visitor’s experience, three central themes were identified: emotional engagement, imagination, and memorability. Participants also made suggestions as to how the experience could have been improved considering factors of authenticity and participation. These findings solidify storytelling’s relevance in heritage tourism contexts, as well as offer a preliminary guide as to how to implement storytelling in the experience design of a heritage attraction or museum.
- Assessment of the marine biodegradation and suitability of textile carrier substrates for Zostera marina transplantationPublication . Rautenbach, Sarah A.; Engelen, Aschwin Hillebrand; Troch, Marleen De; Pieraccini, RiccardoSeagrass meadows provide essential eco-system services for humankind but have been declining over the past and still ongoing, mainly attributed to anthropogenic disturbances. The development of cost-effective and large-scale strategies for seagrass restoration has been challenging. In this study fundamental knowledge was generated to identify textile fabrics from natural derivatives to serve as carrier substrate for transplantation purposes. In a series of experiments the biodegradation behavior of textiles was assessed, differing in material and design. Specimen were buried in the intertidal of the Ria Formosa Lagoon and retrieved after set intervals. Weight, tensile strength and oxygen consumption rate were used as descriptors for biodegradation. The least degraded fabric was composed from coir, followed by the jute and sisal layouts, which performed similarly. The response of Zostera marina shoots towards the textiles was analyzed by placing shoots, incorporated into the fabrics, into mesocosms. Survival rates along with the development of new leaves was higher in shoots growing on sisal layouts than in controls and shoots in coir nets. This study demonstrated that the fixation of the plants onto a dense mesh as the sisal one offers significant support for shoots to grow on, resulting in superior health compared to single lose shoots. Additionally, earlier induced biodegradation in sisal layouts possibly fostered shoots with plant-growth-supporting substrates, according to the health state of these shoots. Hence, time of biodegradation was found to be vital for seagrass transplantation. Rapid degradation, leaving no carrier substrate as in controls and fertilized shoots, was proven to reduce survival chances. Retarded degradation like in coir fabrics, decelerates the supply of growth supporting substrates. Concluding, the dense sisal mesh was found to be the most successful fabric for transplantation of Zostera marina due to its biodegradation rate, high tensile strength, facilitating handling, along with sufficient fixation of the shoots.
- Caracterização da proteína Mob4 humana: um estudo da execução da mitosePublication . Colaço, Andreia Isabel Gonçalves; Tavares, Álvaro; Baião, InêsA divisão celular é um processo essencial à manutenção da vida e à reprodução dos organismos, sendo, por consequência, um processo altamente regulado. No laboratório Cell Cycle and Cancer Biology Group pretende-se compreender este processo, recorrendo-se à Drosophila melanogaster e a células humanas como modelos. A proteína Mob4 é altamente conservada na natureza, constituindo uma das principais proteínas que formam o complexo STRIPAK, no entanto escasso é o conhecimento acerca das suas funções biológicas. Resultados anteriores do laboratório apontam para um papel essencial da proteína Mob4 na regulação e execução da mitose, nomeadamente na formação do fuso mitótico e no correto alinhamentos dos cromossomas mitóticos. Com este estudo, pretende-se elucidar qual a função biológica e molecular da Mob4, incluindo no processo de divisão celular, recorrendo, para tal, à criação de linhas celulares Mob4 nulas, em células humanas tumorais (HeLa) e não tumorais (hTERT RPE-1). Estas linhas permitem, simultaneamente, a avaliação da localização subcelular da Mob4 e o seu possível papel noutros processos celulares. Os resultados obtidos neste estudo segurem que a proteína Mob4 se pode associar ao organelo membranar Golgi, atuando na sua manutenção estrutural e no transporte vesicular. A Mob4 interage também com filamentos do citoesqueleto, ao que tudo indica filamentos de actina, podendo desta forma contribuir para a regulação do citoesqueleto celular, nomeadamente a nível estrutural e na mobilidade celular. Por fim, em mitose, os resultados apresentados neste estudo confirmam os resultados previamente obtidos no laboratório, indicando que a Mob4 poderá estar associada aos centrossomas e aos cinetocoros, contribuindo para a estabilidade da ligação microtúbulos-cinetocoros e sendo necessária para a progressão da mitose. Concluindo, a Mob4 é uma proteína que aparenta estar envolvida em diversos processos biológicos essenciais, nomeadamente, na mitose, podendo ser uma das proteínas que regula este processo.
- Lipid nanoparticles for therapeutic proteins deliveryPublication . Seck, Fatumata Ramadana Gomes; Fonte, Pedro Ricardo Martins Lopes daTherapeutic proteins are bioactive compounds used for the treatment and prevention of several diseases. These compounds are usually well-tolerated, present a high specific activity, few adverse reactions, and a wide range of applications. Nevertheless, they also present physicochemical instability, with susceptibility to suffer degradation. The use of nanocarrier systems protects the protein structure, improve its bioavailability and enhance its sustained or controlled release. There has been an emerging interest in lipid nanoparticles as carriers for drug delivery. Solid lipid nanoparticles (SLN) are considered the first-generation of lipid nanoparticles, composed of a solid lipid matrix of one or more biocompatible and biodegradable lipids, solid at both room and body temperature. Nanostructured lipid carriers (NLC) are the second generation of lipid nanoparticles, on which the solid lipid matrix is replaced by a blend of liquid and solid lipid. The incorporation of a liquid lipid increases the imperfections in the matrix core which allows an increased encapsulation efficiency and decreased expulsion of the encapsulated drugs during storage. Nevertheless, the application of the NLC for the encapsulation of therapeutic proteins is not well established yet and it urges the need to optimize production methods that do not compromise the protein structure during the encapsulation process. We have optimized the production of an insulin-loaded NLC formulation achieving a particle size of about 200 nm, zeta potential of -18 mV and more importantly, an encapsulation efficiency of about 85% and loading capacity of 11%, which are promising features for different applications. Therefore, the objective of this work was to address the use of lipid nanoparticles for therapeutic proteins delivery. Thus, using insulin as a model protein, it was developed a production method to encapsulate therapeutic proteins into NLC. It is foreseen the opening of a new paradigm in the delivery of therapeutic proteins using NLC.