Browsing by Issue Date, starting with "2022-12-12"
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- A numerical study of submesoscale processes in the coastal circulation of MadeiraPublication . Gareau, Jonathan; Martins, Flávio Augusto Bastos da Cruz; Janeiro, João; Caldeira, RuiSubmesoscale processes are defined geometrically by a lower length scale than the first baroclinic radius of deformation and dynamically by a Rossby number (Ro) of O(1), thus virtually unaffected by planetary forces. They have been widely studied in various environments using in-situ measurements, remote sensing, and numerical modelling. However, due to their unpredictable nature and relatively short spatial and temporal scales, identifying submesoscale patterns is a difficult task. Therefore, abundant ongoing research is continuously seeking new insight on their irregular behavior in the ocean. Recent observations of submesocale structures have shown their efficiency in transporting particles horizontally and vertically in both the open ocean and coastal waters. Oceanographic studies concerning the deep-sea island of Madeira have mainly focused on mesoscale processes but have yet to describe features found at the submesoscale. Based on the recent discovery of a coastal current over Madeira’s insular shelf, this study attempts to assess the role of submesoscale processes on the island’s coastal circulation and the main physical forcings responsible for their generation. A coupled ocean-atmosphere model (COAWST) was used to simulate oceanic outputs within 1-km resolution grids, from which Eulerian properties of the flow field were calculated to detect submesoscale activity in the area. In addition, 4 simulations were run according to different forcing scenarios: (A) all forcings (wind, tides, geostrophic); (B) wind forcing; (C) tidal forcing; (D) geostrophic far-field forcing. Results show that submesoscale activity was generally concentrated near the coast and mostly attributed to wind and geostrophic forcings. Eddies with Ro larger than 1 were found in Madeira’s wake and/or on the fringes of mesoscale eddies interacting with the island’s shallow bathymetry, which is in line with the literature. These small-scale eddies were the dominant feature within the coastal circulation, suggesting their important contribution to the material transport along the shelf.
- A economia circular no alojamento turístico em PortugalPublication . Dantas, Samara Santiago; Santos, Margarida C.Esta dissertação aborda a temática da economia circular (EC) e sua aplicação pelo setor de alojamento turístico em Portugal. Apesar de sua inegável importância econômica e social a nível mundial, o setor do turismo gera externalidades negativas, principalmente, ambientais. Um dos caminhos para que o turismo alcance os objetivos da sustentabilidade está relacionado à mudança de uma perspectiva linear de produção e consumo para um contexto de circularidade. Nesse sentido, a indústria do turismo pode e deve implantar os conceitos e práticas de EC, obtendo vantagens competitivas, de inovação e potencial de criação de valor. O objetivo desta investigação consiste em explorar o atual cenário de aplicação das práticas de EC pelo setor de alojamento turístico em Portugal. O estudo exploratório, caracterizado por uma revisão de literatura, busca compreender o conceito de EC e como este tem sido adotado pelo setor. A pesquisa empírica, de caráter quali-quantitativo, dedica-se a aferir a adoção destas práticas nos diferentes tipos de alojamentos em Portugal, considerando as dimensões mais relevantes identificadas na literatura: gestão, construção e reforma, eficiência energética e hídrica e gestão dos resíduos. Os dados recolhidos de uma amostra não-probabilística de 151 questionários sugerem que, de maneira geral, práticas sustentáveis e de EC estão sendo implementadas pelas empresas de alojamento turístico portuguesas, em maior ou menor grau. Enquanto algumas ações implementadas se mostraram mais básicas, e, portanto, mais associadas a práticas de sustentabilidade, práticas mais robustas, que seriam consideradas mais circulares, também foram identificadas, como o uso de energia renovável e painéis solares, o aproveitamento de águas de qualidade inferior e a realização de compostagem dos resíduos orgânicos. As descobertas deste estudo fornecem, portanto, uma melhor compreensão sobre a relação da EC e a indústria do turismo e seus benefícios, podendo ser úteis para investigadores, criadores de políticas e profissionais do setor.
- Assessment of Wild Rocket (Diplotaxis tenuifolia (L.) DC.) Germplasm accessions by NGS identified SSR and SNP markersPublication . Reis, João M.; Pereira, Ricardo; Coelho, Paula S.; Leitão, JoséRocket is the common designation for two baby-leaf salad crops of the Brassicaceae family: Eruca sativa (L.) Cav., usually referred to as annual garden rocket, and Diplotaxis tenuifolia (L.) DC. commonly named to as perennial wild rocket. E. sativa is used for human consumption since antiquity. However, the growing consumer preference for D. tenuifolia is being accompanied by the fast increase in its production area and commercialization of new cultivars. Nevertheless, the worldwide number of wild rocket accessions maintained in germplasm collections is very reduced, the solution for which situation the project “REMIRucula” intends to contribute, establishing a germplasm collection at the INIAV, Oeiras, Portugal. Herein, we report on the establishment via next generation sequencing (NGS) of the first genome assembly of D. tenuifolia and the identification of specific single sequence repeat (SSR) and single nucleotide polymorphisms (SNP) loci for the establishment of specific DNA-markers for this species. A representative set of 87 D. tenuifolia and 3 E. sativa accessions were assessed by 5 SSR and 9 SNP-CAPS markers, allowing a drastic discrimination between both species and the establishment of unequivocal molecular fingerprints for the analyzed accessions. The non-discrimination within six pairs and one trio of D. tenuifolia accessions is discussed.
- The role of vitamin K in osteoporosisPublication . Cristafovici, Nicoleta; Simes, Dina; Viegas, Carla Alexandra São BentoAccording to the World Health Organization (WHO), osteoporosis is a “progressive systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture." The consequences of these fractures can be serious, sometimes life-threatening; the economic costs of treating fractures are also considerable. Alternative methods of treating osteoporosis have been researched in recent decades, and vitamin K (VK) has been found to be a viable therapeutic. This dissertation investigates scientific evidence on the role of VK in osteoporosis. VK is a fat-soluble vitamin required for blood clotting. VK has two main structures: vitamin K1 (VK1) and vitamin K2 (VK2). Different absorption rates, tissue distribution, and bioavailability reflect structural differences between VK1 and VK2. Although they have structural differences, both function as co-factor for the γ-glutamyl carboxylase enzyme (GGCX) in the conversion of glutamic acid (Glu) residues into γ-carboxyglutamic acid (Gla) residues in vitamin K-dependent proteins (VKDPs), involved in hepatic and extrahepatic activity. VKDPs involved in bone metabolism include osteocalcin (OC), matrix G1a protein (MGP), Gla Rich Protein (GRP), Growth Arrest Specific Protein 6 (Gas6), and protein S. OC is the most abundant VKDP in bone. During bone mineralization, osteoblasts produce OC, which binds to calcium ions and hydroxyapatite crystals to modulate bone size and structure. According to studies, VK2, especially menaquinone-7, has more positive results than VK1 in terms of improving bone mineral density (BMD) and decreasing the risk of fractures. In addition, VK2 suppresses IKB phosphorylation and reduces NF-κB activation, resulting in a decrease in the generation of pro-inflammatory cytokines implicated in osteoporosis physiopathology. VK2 also acts as a ligand for the steroid and xenobiotic receptor (SXR) or pregnane X receptor (PXR), increasing the transcription of genes for extracellular matrix proteins to preserve bone structure.
- Intellectual capital of Technology-Based IncubatorsPublication . Martins-Rodrigues, M. Carolina; Barbosa, Raul Pommer; Barbieri da Rosa, Luciana Aparecida; Sousa, Maria José; Zavatti Campos, Waleska Yone YamakawaThe objective of this work is to evaluate the associations between the intellectual capital of technology-based incubators in the sustainability of incubated companies located in Portugal. For this purpose, the methodological strategy employed was the survey, and to test the hypotheses the Partial Least Squares Structural Equation Modeling PLS-SEM method was applied from a sample of 82 incubated company managers. The results show that the intellectual capital of the incubator company has a direct and positive relationship with the innovative capacity, satisfaction, and sustainability of the incubated company. In turn, the incubated company’s innovative capacity has a direct and positive impact on sustainability itself. In addition, both the sustainability of the incubated company and its levels of satisfaction with the incubated company has a positive and direct impact on its competitive success. The management implications include the perception that the greater the effort to improve the human capital, structural capital, and relational capital of the incubated companies, the better will be the results achieved in supporting companies, helping start-ups develop sustainably and competitively in the market.
- Biodegradation of paracetamol and its intermediate metabolite hydroquinone by bacterial strains isolated from two mines of the iberian pyrite beltPublication . Ismail, Fatma M.A. Elsayed; Costa, Maria Clara; Carlier, Jorge DiasThe main objective of the current study was to isolate bacterial strains able to biodegrade the emerging pollutants paracetamol (APAP) and hydroquinone (HQ), amongst the most worldwide prescribed drugs, also frequently detected in wastewater treatment plants influents and effluents and the environment. The most promising microbial consortia of Poderosa and Lousal mines for APAP removal were selected based on the previous reports of PROBIOMA project (European Regional Development Fund ERDF - Interreg V-A Spain-Portugal program (POCTEP)). The ability of the selected microbial consortia to remove APAP from the Mineral Salt Medium (MSM) at an initial concentration of about 500 mgL-1 (MSM-APAP (500 mgL-1)), under dark shaking conditions of 160 rpm at 25 °C, was confirmed using UV-vis molecular spectroscopy. Subsequently, the isolation step from selected samples proceeded from three successive enrichment cultures using MSM-drug (500 mgL-1) under the aforementioned conditions by spreading first on LB-drug and then on MSM-drug (500 mgL-1) agar plates and resulted in seven isolates able to utilize APAP as sole carbon source, and identified according to 16S rRNA gene sequence analysis as members of genera Aeromonas, Bacillus (two isolates), Niallia, Paraburkholderia, Rhizobium, and Variovorax, as well as one HQ utilizing isolate (Mycolicibacterium sp.). The HPLC analysis of APAP removal, in MSM-APAP (500 mgL-1) under the same culture conditions, by the two putative APAP biodegrading Bacillus sp. isolates revealed that Bacillus sp. (PDE3.1) showed maximal APAP %removal of 63+3 after 18 days, while Bacillus. sp. (PLC2.1) showed %removal of only 8+1 at the end of the experiment after 21 days. The key metabolites of APAP degradation (4-aminophenol and HQ) were detected through GC-MS analysis in the experiment with Bacillus sp. (PDE3.1) at very low concentrations. Then, the seven potential APAP biodegrading bacterial isolates were tested for APAP removal in MSM at a lower concentration of 50 mgL-1. Rhizobium sp. (PDE3.3) and Paraburkholderia sp. (PLA3.3) seemed the most promising where APAP %removal was 49±4 and 47.9±0.9, respectively. Later, the co-culture of the three most promising isolates (Rhizobium sp. (PDE3.3), Paraburkholderia sp. (PLA3.3), and Bacillus sp. (PDE3.1) didn’t improve the %removal compared with the pure cultures, while the co-culture with the seven potential APAP biodegrading isolates did not show removal capacity. Mycolicibacterium sp. (HPB1.1) showed at least 88% removal of HQ from MSM-HQ (50 mgL-1) after four days; hence, was checked for APAP removal in MSM-APAP (50 mgL-1) and showed APAP %removal of 41.6±0.1. Overall, some bacterial strains isolated from Poderosa and Lousal mines showed removal capacity; hence, more efforts should be directed at investigating if biodegradation is the main removal mechanism involved, and at exploring the biodegradation potentials of The Iberian Pyrite Belt mines associated bacteria.
- O Teletrabalho e a sua implementação em instituições de Ensino Superior em Portugal durante a Pandemia da Covid-19Publication . Carapinha, David Curtinha; Contreiras, Joaquim; Duarte, Ana PatríciaO teletrabalho, enquanto modalidade do exercício da atividade laboral, é uma realidade muito anterior à pandemia da covid-19. Contudo antes desta, em Portugal, mesmo nos setores mais propícios à sua adoção, nomeadamente no setor terciário, não se verificava uma implementação generalizada do trabalho à distância com recurso a tecnologias da informação e comunicação. A pandemia forçou essa conversão do trabalho presencial em trabalho à distância, nalguns casos com ganhos de produtividade, competitividade e economia de recursos que certamente permanecerão para lá do horizonte pandémico. Neste âmbito, as instituições de ensino superior não foram uma exceção e, ao ritmo da evolução da pandemia, foram forçadas a implementar o teletrabalho de forma mais ou menos generalizada, com impactos na GRH (Gestão de Recursos Humanos). Os objetivos deste estudo são analisar a implementação do teletrabalho em instituições do ensino superior português, durante a pandemia da covid-19, e compreender os seus impactos na GRH. Para a prossecução dos objetivos deste estudo, em termos metodológicos, procedeu-se a uma revisão de literatura e à aplicação de um questionário online com posterior análise quantitativa dos dados recolhidos. Em conclusão, a maioria dos/as inquiridos/as está satisfeita com a situação de teletrabalho, tendo este modo de prestar a atividade laboral contribuído para a existência de mais tempo disponível para a vida pessoal e familiar.
- Psoríase e produtos naturaisPublication . Figueiredo, Diana Sofia Abreu; Miguel, Maria GraçaA psoríase é uma doença inflamatória crónica do foro dermatológico que afeta cerca de 2-3% da população mundial. A sua etiologia não é inteiramente compreendida, no entanto, reconhece-se o seu carácter multifatorial em resultado da interações de fatores intrínsecos e extrínsecos ao organismo. Clinicamente caracteriza-se pela presença de placas eritematosas descamativas, por vezes associadas a prurido. Existem diversos padrões de apresentação clínica que variam de acordo com a extensão e localização das lesões que podem, em casos mais graves, levar ao desenvolvimento de comorbilidades que impactam negativamente o bem-estar dos doentes. Tratando-se de uma doença crónica, o objetivo terapêutico passa por induzir e manter a remissão dos sintomas. De acordo com a severidade e extensão das manifestações clínicas podem ser utilizados agentes tópicos, fototerapia ou agentes sistémicos, onde se inserem os agentes biológicos. Todas estas opções, por serem utilizadas a longo prazo, estão associadas a risco de perda de eficácia, efeitos secundários e possível toxicidade, o que pode comprometer a adesão à terapêutica por parte dos doentes. Os produtos naturais suscitam interesse desde há milhares de anos na área da dermatologia e atualmente, o panorama mantém-se no que diz respeito à psoríase. Neste contexto, a utilização de produtos naturais surge como uma alternativa ou adjuvante terapêutico com o objetivo de reduzir e impedir a progressão da sintomatologia, assim como garantir uma utilização prolongada segura, com o mínimo de efeitos secundários possível. Deste modo, o presente trabalho incide sobre a vantagem dos produtos naturais no tratamento da psoríase, abordando algumas das espécies com potencial e as suas características.