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- Enhancement of the antioxidant response in gilthead seabream (Sparus aurata) juveniles through dietary algal supplementationPublication . Bolinhas, João Miguel Ramos; Teodósio, Rita; Engrola, SofiaFish in aquaculture are exposed to stressors such as handling and transport, which can lead to oxidative stress, compromising cellular integrity. Dietary intervention involving bioactive compounds can improve resilience and mitigate such damage. This study investigated the impact of algae-supplemented diets on the antioxidant and immune response of juvenile gilthead seabream following a short feeding trial and a subsequent stress challenge. A seven-day feeding trial was conducted using four diets: a control commercial-like diet (CTRL) and three alternatives supplemented with processed Tisochrysis lutea biomass (Tiso), Tisochrysis lutea biomass combined with Gelidium sp. extract (TisoG), and Tisochrysis lutea biomass and Skeletonema costatum extract (TisoS). Following the feeding trial, the challenge involved standardized events and infection with a pathogen (Photobacterium damselae subsp. piscicida) to assess if fish antioxidant responses were affected by the dietary treatments. Liver samples were collected post-feeding trial (Sampling 1-S1) and 6 hours post-infection (Sampling 2-S2) to evaluate growth performance, oxidative stress biomarkers, and expression of antioxidant and immune-related genes. Algae-supplemented diets had no negative effects on growth, feed efficiency, or survival. At S1, the TisoG group had significantly lower superoxide dismutase (SOD) activity and total antioxidant status (TAS) compared to other treatments. No differences were found in lipid peroxidation (LPO) or catalase (CAT) activity. At S2, SOD activity increased in Tiso, and TAS significantly increased in TisoG, with CAT and LPO remaining unaffected by diet. Gene expression at S1 showed no significant changes in oxidative stress markers, although igm was downregulated in Tiso and il-1β upregulated in TisoS. No differences were found in il-10, tnf-α, or hsp70. After S2, gpx1 was upregulated in CTRL and TisoG, sod2 was suppressed in TisoS, and nrf2 declined in all algae-fed groups. il-10 and tnf-α were highest in CTRL and significantly lower in TisoS. The Tisochrysis lutea and Gelidium extract diet was the most effective blend in enhancing antioxidant capacity and stress-related gene expression, especially after the challenge.
- Abordagem integrada para a identificação, análise e mitigação de riscos ocupacionais no banco alimentar do Algarve: aplicação dos métodos Marat, Niosh e William T. FinePublication . Oliveira, Sérgio António Fonseca de; Sousa, AntónioO presente trabalho teve como objetivo identificar, analisar e mitigar os riscos ocupacionais associados às atividades logísticas desenvolvidas nas unidades de Faro e Portimão do Banco Alimentar do Algarve. Para tal, adotou-se uma abordagem metodológica integrada, que conjuga os métodos MARAT, NIOSH e William T. Fine. A aplicação do MARAT permitiu uma avaliação sistemática dos riscos existentes, com a atribuição de Níveis de Intervenção (NI), destacando-se diversos riscos classificados como NI I e NI II, exigindo atuação imediata ou prioritária. A aplicação da equação de NIOSH permitiu calcular os Índices de Levantamento (IL), demonstrando a eficácia potencial de medidas corretivas simples. O método de William T. Fine foi aplicado aos riscos classificados como NI I, permitindo hierarquizar essas intervenções com base no custo e na urgência. As propostas incluem reorganização do layout, aquisição de equipamentos ergonómicos e formação dos colaboradores. Os resultados revelaram contrastes significativos entre as duas unidades: Faro apresenta condições estruturais deficitárias, com layout improvisado e elevada exposição a riscos ergonómicos e mecânicos; Portimão, por sua vez, dispõe de uma estrutura mais adequada, mas enfrenta desafios na organização dos fluxos logísticos e no empilhamento em altura. Foram propostas medidas corretivas ajustadas à realidade de cada unidade, incluindo soluções técnicas e organizacionais, formação prática, delimitação de espaços e aquisição de equipamentos ergonómicos de apoio. Este estudo reforça a importância da avaliação de riscos com recurso a metodologias combinadas, demonstrando a sua aplicabilidade em contextos logísticos do setor social, muitas vezes desprovidos de soluções sistematizadas. Os resultados obtidos permitem não só melhorar as condições de trabalho nas unidades analisadas, como também oferecer um modelo de referência replicável por outras organizações com dinâmicas semelhantes.
- Effects of environmental enrichment on inhibitory control in juvenile gilthead seabream (Sparus aurata): a cognitive study using the cylinder taskPublication . Neves, Inês; Cabrera-Álvarez, María J.; Saraiva, João L.Inhibitory control is a key component of executive function, influencing adaptability and decision-making in animals. Consequently, this study aims to investigate whether environmental enrichment (EE) enhances inhibitory control in juvenile gilthead seabream (Sparus aurata) using the cylinder task. As aquaculture rapidly expands to meet global food demands, the welfare of farmed fish species, such as seabream, has become a critical concern. EE, which involves introducing elements that stimulate fish physiologically and psychologically, has shown significant benefits in various species, including enhanced learning, memory, and stress resilience. This study used 40 juvenile seabreams housed in tanks with and without enrichment to test their cognitive abilities through a series of progressive learning phases. These phases culminate in the Cylinder Task, where fish are challenged to obtain food from a transparent cylinder using the two open ends, evaluating the inhibition of the urge to approach the reward through the transparent walls of the cylinder. All the individuals were previously screened for personality traits (i.e. either more proactive or more reactive). In this study, juvenile gilthead seabream reared in enriched environments exhibited higher behavioral engagement and faster learning during training, with significant improvements in task performance over trials. However, no significant differences in inhibitory control were observed between enriched and non-enriched groups during testing. Instead, larger fish and those with proactive traits, characterized by rapid decision-making and high exploration, performed tasks faster and more accurately. These findings suggest that while EE enhances motivation and learning, inhibitory control may be primarily driven by intrinsic factors like body size and personality rather than environmental complexity, and that adapting EE to individual traits could optimize welfare and efficiency in aquaculture.
- Fine scale behaviour of Labrus bergylta in the National Park Illas Atlánticas of Galicia (NW Spain)Publication . Brand, Lukas; Fernández, Alexandre Alonso; Abecasis, DavidUnderstanding the spatial ecology and behaviour of coastal fishes is critical for the design of marine protected areas (MPAs). Acoustic telemetry, combined with advanced modelling approaches, provides high-resolution insights into residency, activity, and habitat use, key information for a proper design of spatial protection measures. In this study, we acoustically tracked fifteen Labrus bergylta individuals over more than two years within the Atlantic Islands of Galicia National Park, generating over 4.5 million detections. After filtering and excluding fate dates, valid trajectories were reconstructed using Continuous-Time Correlated Random Walk models, yielding more than 3.1 million estimated positions. Residency analyses revealed that 67% (10) of individuals exhibited very high site fidelity (IWR ≥ 0.95), while others showed intermediate fidelity with occasional excursions beyond the array. Only one fish displayed virtually no residency. Estimated activity spaces ranged from 6,870 to 23,120 m², with daytime ranges significantly larger than at night and peaking in late spring–summer, reflecting reproductive activity. Swimming speed was positively related to bottom temperature and showed seasonal variation as well as crepuscular peaks. Hidden Markov Models distinguished two behavioural states (resting vs. active), with an average activity budget of 56.5% resting and 43.5% active. State transitions were influenced by diel cycle and habitat type, though with strong inter-individual variability. Revisitation patterns revealed long-term fidelity to a small number of discrete core areas, located on rocky substrates and often shared across day and night. Overall, L. bergylta exhibited a dual movement strategy of strong site fidelity interspersed with occasional exploratory excursions. These findings confirm the importance of structurally complex hard-bottom habitats as persistent refuges and support the effectiveness of fixed spatial protections. By linking fine-scale behaviour with habitat use over extended timescales, this study advances the ecological understanding of temperate reef fishes and provides robust evidence to inform the management and evaluation of coastal MPAs.
- Assessment of wave overtopping at Praia da Vitória, Terceira, Azores, with SWASH modelPublication . Baddavidana, Dinush Shayaman Priyankera; Pinheiro, Liliana; Garzon, Juan L.; Zózimo, Ana CatarinaThe primary objective of this dissertation is to enhance the accuracy of overtopping predictions using the SWASH (Simulating WAves till SHore) model, for inclusion in the Early Warning System (EWS), HIDRALERTA, currently operational in Praia da Vitória. While existing tools within HIDRALERTA offer valuable insights, they have limitations in accurately representing waves and overtopping details. To address these limitations, this research tested the capabilities of the SWASH model by simulating past storm events and typical wave conditions across the two-dimensional model of the entire port and bay areas with complex coastal structures and bathymetry. Outcomes of the simulations were compared to predictions from the NN_OVERTOPPING2 neural network and observed images from extreme events. In the SWASH model, coastal structures were modelled as impermeable layers, with bottom roughness incorporated to enhance energy dissipation from roughness and seepage. An unstructured triangular mesh was used for the computational domain. Manning’s coefficient for the outer slope of the south breakwater, with tetrapod armour units, was calibrated using a physical model test conducted in February 2025 at the National Laboratory of Civil Engineering (LNEC). The model was replicated in SWASH at prototype scale, using two test cases that resulted in overtopping for calibration. The results demonstrate that the SWASH model effectively simulates wave propagation and overtopping in harbour and bay areas, especially over complex coastal structures. Its accuracy in estimating wave propagation and overtopping is sensitive to wave energy interactions with the bottom and slopes, influenced by the Manning coefficient. While unstructured meshes enable large-domain simulations, the quality of the mesh affects both prediction accuracy and computational time. The model is stable when using implicit time integration but unstable with explicit methods. Despite some simulation instability, most simulations reached the maximum allowed simulation time on the National Distributed Computing Infrastructure (INCD) cluster. The model’s accuracy is heavily dependent on bathymetric data, with results generally aligning with NN_OVERTOPPING2 predictions and observed images from extreme events, although underpredictions can occur. Parallel processing is currently limited to structured grids in SWASH and, there is potential for efficiency improvements with unstructured meshes. Future studies should compare SWASH results with field data to fully assess its performance.
- Vegetation and platform geometry effects on wake attenuation in wetlandsPublication . Uddin, A S M Shanawaz; Carrasco , A. Rita; Fernández, María E. MazaWetlands play a vital role in coastal protection by dissipating wave energy, reducing flooding risks, stabilizing shorelines, and offering sustainable alternative to engineered defenses. Despite extensive research on wind wave attenuation by salt marsh vegetation, further studies are needed to quantify wetlands ability to mitigate the impact of wind and boat generated waves, and enhance their use as a Nature-based Solution towards sustainable coastal protection strategies. The aim of this study was to investigate the role of wetlands vegetation and morphology in dissipating wave energy in the Ria Formosa lagoon, southern Portugal. This was accomplished through a comprehensive analysis of how vegetation characteristics and profile morphology influence wave attenuation, utilizing field measurements and numerical modelling. Specifically, after understanding physical mechanisms and validate the SWAN model, this model was employed to assess the effects of different boat wake intensities, vegetation densities, and platform geometries on wave energy reduction. The results obtained demonstrate that wetland platforms with gentle slopes and around 100 meters length seemed to be the most effective on reducing wave energy, but they only contribute to 10% of the overall wave attenuation, with the remaining attenuation being promoted by the vegetation. Densely vegetated profile achieved 68% wave energy reduction compared to sparse or non-vegetated ones. Zostera noltei provided greater attenuation than Spartina maritima at only higher wave heights. Nevertheless, the occurrence of mixed-species vegetation proved to be more effective than just having single vegetation, for the same geometry. Wave attenuation increased with both wave height and vegetation density, up to a saturation point at around 4800 stems/m2 for Zostera noltei and 1400 stems/m2 for Spartina maritima. These findings suggest that optimizing both biological and platform characteristics is essential for maximizing coastal protection. The research highlights the need for comprehensive field measurements, with diverse ecological settings, tidal dynamics, varied geometries and salt marsh species to more effectively capture complex interactions between waves and wetland ecosystems. The outcomes provide practical recommendations for designing and managing resilient wetlands to support sustainable and adaptive coastal defense strategies.
- Compound flooding on an estuarine environment: case study of tagus estuaryPublication . Romero, Fabian Yesid Soler; Almeida, Luis Pedro; Hervas, Juan L. GarzonThe combined occurrence of coastal, fluvial and/or pluvial flood drivers can lead to compound flood events, which can trigger devastating social, economic, and ecological impacts, particularly in low-lying zones, including estuarine environments. A great number of these areas, which are home to significant populations worldwide, are increasingly at risk, as the intensity, phasing and frequency of such drivers are projected to change. These flood-induced impacts arise from the potential increase in inundation magnitude due to the non-linear interactions between various flood drivers, where their combined effects can exceed the simple sum of their individual contributions. Understanding their joint impacts and accurately estimating compound flood magnitudes is therefore essential for effective coastal management and disaster risk reduction. In this study, a numerical modeling framework was applied to analyze the interaction between different flood drivers (storm surge, peak river discharge, extreme rainfall and astronomical tides) in the Tagus Estuary. The first phase involved a coupled hydrodynamic model (MOHID), implemented to simulate tidal, wave, and current circulation within the estuary using oceanic and riverine boundary conditions. Based on these results, a flood model (SFINCS) was applied to simulate flooding processes along the northern and southern margins of the estuary under various scenarios. The flood model was validated using a storm event that occurred in the study area in December 2022. Subsequently, joint probability and extreme value analysis for 100-year return period values were estimated for the flood drivers and used to define multiple modeling scenarios along with different Sea Level Rise projections. These scenarios were designed to examine the flood driver’s interaction, focusing on the flood magnitudes in the context of compound flooding. This study demonstrated that compound events resulting from the interaction of pluvial/fluvial and coastal drivers can increase flood extent and depth by three to four times compared to events driven solely by coastal forces, such as a storm surge coinciding with spring tides in the estuary. Furthermore, the analysis revealed that rainfall is the primary cause of flooding in the Tagus Estuary.
- Site fidelity and residency patterns of rough toothed dolphins ( Steno bredanensis ) in Madeira Island, using photo identification dataPublication . Raffaelli, Claire; Marçalo, Ana; Sambolino, AnnalisaThe rough toothed dolphin Steno bredanensis ) is a poorly understood odontocete species with a scattered global distribution, particularly in oceanic and insular habitats. In the Eastern North Atlantic, including the waters surrounding Madeira, their habitat use and movement patterns remain largely unknown. This study presents the first long term assessment of site fidelity and residency of rough toothed dolphins in Madeira using photo identification data . A total of 63 7 distinct individuals were identified during 160 days of sampling occasions between 2016 and 2024 , based on distinctive dorsal fin markings (3 4) and high image quality (2 4)4). Using Lagged Identification Rates, residency modeling, and site fidelity indices, temporal patterns of occurrence and return were analyzed . The discovery curve did not reach an asymptote, and 6 2 5 % of individuals were seen only once, suggesting an open population. The best fit residency model estimated that at any given time, ~28 individuals are present, with an average stay of 6.7 days and absence of ~1700 days, indicating transient usage of the a rea. However, a subset of individuals exhibited recurrent visitation patterns. The c luster analysis of site fidelity indices revealed two distinct patterns: a larger group with intra and interannual fidelity chara cterized by short term, periodic visits; and a smaller group with inter annual fidelity and longer presence spans. These findings point to ecological heterogeneity within the population, potentially driven by individual preferences, social structure, or en vironmental factors. Despite these variations, the overall metrics point to a limited and discontinuous use of the region. In conclusion, rough toothed dolphins show generally low site fidelity to Madeira, as evidenced by short residence durations, long ab sences, and low re sighting rates. These results align with their presumed ecological preference for wide ranging movements in oceanic habitats. Understanding this spatio temporal variability is crucial to inform conservation efforts, particularly in dynam ic and low density contexts typical of pelagic cetaceans.
- Efeitos rápidos e lentos na tarefa de Stroop emocional: Influência da frequência lexicalPublication . Gonçalves, Mariana Filipa Ferreira; Faísca, Luís Miguel MadeiraA tarefa de Stroop Emocional tem sido utilizada frequentemente para avaliar mecanismos automáticos de deteção de estímulos com valência emocional em populações clínicas. O efeito mais comum nesta tarefa, intitulado efeito rápido, é a lentificação da resposta à cor de palavras de valência emocional negativa. Contudo, McKenna e Sharma (2004) descreveram um segundo fenómeno, denominado efeito lento, que consiste na lentificação da resposta à cor de palavras neutras antecedidas por uma palavra negativa. Permanecem, no entanto, por esclarecer as condições em que este efeito emerge e se o mesmo depende de outras caraterísticas do estímulo além da sua valência, nomeadamente de propriedades lexicais, como a frequência. O presente estudo teve como objetivo avaliar, na população geral, a presença de efeitos rápidos e lentos na tarefa de Stroop Emocional e analisar se esses efeitos são moderados pela frequência lexical do estímulo. Participaram 33 jovens adultos, com idades entre os 19 e os 29 anos, que realizaram uma versão mista da tarefa de Stroop Emocional. Os resultados revelaram um efeito rápido, com respostas mais lentas na nomeação da cor de palavras de valência negativa, mas não evidenciaram um efeito lento significativo. Observou-se, contudo, uma interação entre a frequência das palavras e a valência, moderando a magnitude de ambos os efeitos, que apenas se manifestaram em palavras de baixa frequência. Estes resultados não são conclusivos quanto à presença de efeito lento no Stroop Emocional, nas condições e amostras testadas, mas sugerem que características lexicais do estímulo podem interferir na magnitude dos efeitos, sejam eles rápidos ou lentos.
- Intervenções de segurança na prevenção de quedas na construção civil - uma revisão sistemáticaPublication . Silva, Ingrid Polyana Gomes da; Costa, Rui Carlos Gonçalves Graça eA construção civil é um dos setores com maior incidência de acidentes de trabalho, sendo as quedas uma das principais causas de lesões graves e fatalidades. Esta revisão sistemática teve como objetivo identificar os fatores de risco mais comuns associados aos acidentes por quedas no setor da construção civil, e avaliar as estratégias mais eficazes para sua prevenção. A pesquisa seguiu as diretrizes do PRISMA 2020 e utilizou o modelo PICO para a formulação das perguntas de pesquisa. Foram incluídos seis estudos primários (quantitativos e mistos), publicados entre 2020 e 2024, em idioma inglês ou português, extraídos das bases de dados: B-On, Web of Science e PubMed. A análise qualitativa revelou que os principais fatores associados às quedas são: comportamentos inseguros dos trabalhadores, condições inseguras no local de trabalho, falhas na gestão e supervisão, além de barreiras de comunicação. As intervenções mais eficazes incluem treino contínuo, uso e fiscalização de EPIs (Equipamentos de Proteção Individual) e EPCs (Equipamentos de Proteção Coletiva), planeamento seguro das atividades e promoção de uma cultura organizacional de segurança. Conclui-se que a prevenção de quedas exige uma abordagem integrada que vá além das normas técnicas, incorporando gestão eficiente, formação constante e compromisso coletivo com a segurança.