Browsing by Issue Date, starting with "2022-04"
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- Fluctuations in the wage gap between vocational and general secondary education: lessons from PortugalPublication . Raposo, Pedro Miguel; Hartog, Joop; Reis, HugoWe document and analyse the wage gap between vocational and general secondary education in Portugal between 1994 and 2013. As Portuguese workers have been educated in different school systems, we have to distinguish between birth cohorts. Analysing the wage gaps within cohorts, we find no support for either the human capital prediction of crossing wage profiles or the hypothesis that general graduates increasingly outperform vocational graduates in late career. We discover that the life- cycle wage profiles have shifted over time. We link the pattern of shifting cohort profiles to changes in the school system and in the structure of labour demand. We conclude that assessing the relative value of vocational education requires assessing how the vocational curriculum responds to changes in economic structure and technology. We show that the decline in assortative matching between workers and firms has benefited vocationally educated workers.
- Ciberterrorismo e a lei de combate ao terrorismoPublication . Freitas, Pedro MiguelPartindo de uma análise da doutrina internacional em torno da conceptualização do ciberterrorismo, pretende-se com este artigo aferir se a Lei n.º 52/2003 prevê e pune também esta forma de aparecimento de terrorismo. As inúmeras aceções de ciberterrorismo podem ser reconduzidas a ciberterrorismo em sentido estrito ou ciberterrorismo em sentido amplo. A lei portuguesa, ainda que não tomando uma posição evidente sobre esta distinção, consagra a previsão e punição de ambas as modalidades.
- Evolving conceptions of work-family boundaries: in defense of the family as stakeholderPublication . Cunha, Miguel Pina e; Hernández-Linares, Remedios; Sousa, Milton de; Clegg, Stewart; Rego, ArménioIn the management and organization studies literature, a key question to explore and explain is that of the family as an organizational stakeholder, particularly when working-from-home became the “new normal”. Departing from meta-analytic studies on the work-family relation and connecting with scholarly conversation on work-family boundary dynamics, we identify three main narratives. In the separation narrative, work and family belong to different realms, and including the family in the domain of organizational responsibility is seen as pointless. The interdependence narrative stresses that organizations and families are overlapping domains in which it is important to acknowledge that the policies and practices of the former might have an impact on family life, and vice-versa. The embeddedness narrative, brought to the fore by the COVID-19 pandemic, sees employment and family as progressively convergent and hybrid work domains. The evolution of employment relations towards increased hybridity of the work situation being embedded in the familial/household context increasingly calls for consideration of the family/household as an integral rather than a peripheral stakeholder.
- Avaliação da oferta alimentar nas máquinas de vending de produtos alimentares da Universidade Católica Portuguesa do campus do PortoPublication . Resende, Verónica; Correia, Marta; Cardoso, Maria Lopes; Martins, Ana Pimenta
- First bioactive characterization of the skin mucus from Portugal coastal fish halobatrachus didactylusPublication . Cunha, Marta; Coscueta, Ezequiel R.; Brassesco, Maria Emilia; Almada, Frederico; Gonçalves, David; Pintado, ManuelaThe marine environment has several promising features for the discovery of new molecules. The oceans have half of the planet’s biodiversity and are a harsh environment for aquatic organisms challenging them to have a set of bioactive molecules to survive [1]. It is well known the mucus secreted by fish epidermis works as a defense barrier against harmful elements from the external environment [2]. Therefore, this study aimed to explore some bioactive properties such as antimicrobial activity (agar drop diffusion method), antioxidant activity (ABTS and ORAC scavenging assays) and ACE inhibitory activity (iACE) exerted by the mucus collected scraping the Halobatrachus didactylus skin, from the Tagus estuary. Direct drop application did not show inhibitory activity on the growth of E. coli and S. aureus. The protein contentin the mucus, determined by the bicinchoninic acid methodology, was 13260 ± 342 μg BSA/mL. The antioxidant activity resulted in 1.49 ± 0.04 μmol TE/mL for ABTS and 5.47 ± 0.8 μmol TE/mL for ORAC. iACE resulted in an IC50 of 60 ± 7 μg protein/mL. Also, a peptidic profile of the mucus was obtained through size exclusion chromatography showing a shortchain peptide profile (> 3000 Da) as general distribution, which is consistent with the observed bioactivities. In conclusion, fish mucus peptide fraction showed potential as an antioxidant and even more so as an antihypertensive, but not as an antimicrobial. Furthermore, more studies are needed to discover the key molecules behind these bioactivities.
- Comparative analysis between synthetic vitamin E and natural antioxidant sources from tomato, carrot and coriander in diets for market-sized dicentrarchus labraxPublication . Pereira, Ricardo; Costa, Mónica; Velasco, Cristina; Cunha, Luís M.; Lima, Rui C.; Baião, Luís F.; Batista, Sónia; Marques, Alexandra; Sá, Tiago; Campos, Débora A.; Pereira, Miguel; Jesus, Diva; Fernández-Boo, Sergio; Costas, Benjamin; Pintado, Manuela; Valente, Luisa M.P.Synthetic vitamin E is commonly used in aquafeeds to prevent oxidative stress in fish and delay feed and flesh oxidation during storage, but consumers’ preferences tend towards natural antioxidant sources. The potential of vegetable antioxidants-rich coproducts, dried tomato (TO), carrot (CA) and coriander (CO) was compared to that of synthetic vitamin E included in diets at either a regular (CTRL; 100 mg kg−1) or reinforced dose (VITE; 500 mg kg−1). Natural antioxidants were added at 2% to the CTRL. Mixes were then extruded and dried, generating five experimental diets that were fed to European sea bass juveniles (114 g) over 12 weeks. Vitamin E and carotenoid content of extruded diets showed signs of degradation. The experimental diets had very limited effects on fish growth or body composition, immunomodulatory response, muscle and liver antioxidant potential, organoleptic properties or consumer acceptance. Altogether, experimental findings suggest that neither a heightened inclusion dose of 500 mg kg−1 of vitamin E, nor a 2% inclusion of natural antioxidants provided additional antioxidant protection, compared to fish fed diets including the regular dose of 100 mg kg−1 of vitamin E.
- A filosofia da cultura de José Ortega y GassetPublication . Morujão, CarlosEste ensaio aborda a teoria da cultura do filósofo espanhol José Ortega y Gasset na base de duas noções fundamentais: a de virtual e a de segurança, as quais apenas se tornaram possíveis a partir da “viragem” fenomenológica do autor, nos anos que antecederam a Primeira Grande Guerra. Esta teoria fenomenológica da cultura caracteriza-se por três ideias fundamentais. Em primeiro lugar, Ortega defenderá que a cultura é constituída por um conjunto de noções que servem para a vida, é uma criação intersubjectiva com pretensão de verdade e de objectividade, correndo o risco de, se o não for, se transformar numa impostura. Em segundo lugar, que, pela cultura, exprimimos aquilo que em cada coisa vai para lá dela e remete para todas as outras, constituindo a dimensão de profundidade que está latente no que, em cada uma, é patente. Em terceiro lugar, que a cultura significa claridade da visão, o que Ortega chama, também, conceito: assim, a cultura, não sendo a vida nem as suas profundezas, é o comentário à vida, não no sentido de algo de acessório, mas sim como a própria vida conduzida à sua plenitude.
- Geração Z e dependência online em contexto pandémicoPublication . Silveira, Patrícia; Petrella, SimoneEsta investigação tem como objeto as perceções de jovens adultos universitários – entendidos como geração Z - sobre as suas práticas mediáticas digitais, em especial durante a pandemia, e as consequências da conexão permanente a estes novos formatos para o desenvolvimento do risco de dependência comportamental expresso através de fatores de risco como alterações de humor, intolerância, irritabilidade e depressão, distúrbios de sono, entre outros. Metodologicamente, foram aplicados inquéritos por questionário a uma amostra de 400 jovens adultos universitários (média de idade de 19,6 anos). Os resultados apontam para um aumento da dependência em relação à Internet durante o confinamento. Mais de metade dos jovens adultos considera que a Internet é indispensável em algumas ocasiões da sua vida, da mesma forma que confessam que sentem algumas das consequências do uso excessivo, como sejam a adição aos sites de redes sociais ou as perturbações de sono.
- Quercus ilex leaf as a functional ingredient: polyphenolic profile and antioxidant activity throughout simulated gastrointestinal digestion and antimicrobial activityPublication . Sánchez-Gutiérrez, Mónica; Gómez-García, Ricardo; Carrasco, Elena; Bascón-Villegas, Isabel; Rodríguez, Alejandro; Pintado, ManuelaQuercus ilex leaf constitute a rich source of bioactive compounds, especially phenolic compounds, with health and technological properties. In this study, the influence of in vitro gastrointestinal digestion on the bioaccessibility and bioactivity of phenolic compounds from ground leaf (GL) and leaf powder extract (PE) was evaluated for the first time. The GL showed an increase in antioxidant capacity, total phenolic content and individual phenolic compounds identified in the oral and gastric phase, decreasing in the intestinal and absorption (dialysis) phases, while PE showed a slight decrease in the oral and gastric phase and a more pronounced reduction in the last phases. Although the content of phenolic compounds and the antioxidant capacity were higher in the initial PE, the bioaccessibility (55.27% in GL vs. 34.23% in PE) and the recovery in the last step of the gastrointestinal tract in the colon-available fraction (29.24% in GL vs. 27.90% in PE) were higher in GL. The PE showed high antimicrobial activity against Escherichia coli, Listeria monocytogenes, Salmonella Typhimurium, Yersinia enterocolitica and Staphylococcus aureus, showing minimum inhibitory concentration values between 1 and 5 mg/mL. These results showed the complexity and richness of Q. ilex PE and GL in phenolics with high antioxidant and antimicrobial activity, underlining their use as a source of biofunctional compounds for the development of novel food additives and nutraceuticals.