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- Storm processes and impacts in high energy geologically controlled barriersPublication . Kümmerer, Vincent; Ferreira, Óscar; Loureiro, CarlosCoastal barriers are dynamic sedimentary landforms exposed to the impacts of coastal storms, with storm-induced erosion and shoreline retreat controlled primarily by the hydrodynamic forcing and barrier morphology. When located in storm-dominated environments, coastal barriers are typically attuned to energetic wave forcing, but extreme events can still result in significant impacts. Moreover, in geologically controlled barrier systems, less studied non dynamic geological controls such as the underlying bedrock topography or sediment availability can also mediate the morphological response to storms. Aiming to investigate the relative importance of geological controls on storm processes and impacts in coastal barriers along high wave energy coasts, this study integrates morphological and hydrodynamic data, satellite imagery and process-based numerical modelling to explore storm response in the Outer Hebrides barriers in the northwest of Scotland. Improvements to storm identification methods, to assessment and morphodynamic modelling of morphological change at contemporary timescales, resulted in more comprehensive characterisation of storm processes and impacts in high energy, geologically controlled barriers. Results indicate that there is an increasing trend in storm duration in the western coast of Scotland, and that more than the intensity of wave forcing, water level has a critical influence on storm response in barriers with a wide and shallow nearshore profile. However, variation in foreshore configuration, particularly the presence and height of intertidal rock surfaces, can induce a shift in the primary control of storm response from the hydrodynamic forcing to the geological control. Thus, geological constraints are shown to be important controls on storm-induced morphological response in coastal barriers, leading to spatial variability in shoreline change. Overall, the results of this thesis outline that the incorporation of geological controls in storm impact assessments, particularly in the context of rising sea-levels, is critical to better understand storm-induced changes in coastal barriers on high-energy, geologically constrained coastal environments.
- Transcriptomic profiling of zebrafish mutant for cdkl5 reveals dysregulated gene expression associated with neuronal, muscle, visual and skeletal developmentPublication . Varela, Tatiana da Conceição Domingos ; Domingos Varela, Débora Cristina; Conceição, Natércia; Cancela, M. LeonorZebrafish is a well-recognized model for studying human genetic disorders. Recently, we proposed the homozygous cdkl5sa21938 mutant zebrafish as a model of CDKL5 deficiency disorder (CDD), a developmental epileptic encephalopathy with diverse symptoms. This study aimed to explore Cdkl5-associated molecular mechanisms in zebrafish and assess their similarity to those in mammals. We conducted RNA sequencing on whole cdkl5−/− zebrafish and wild-type siblings at 5- and 35-days post-fertilization (dpf) to compare their gene expression profiles. Most significant differentially expressed genes (DEGs) were related to muscle, neuronal, and visual systems which are affected in CDD. Gene Ontology analysis revealed downregulated DEGs enriched in muscle development, extracellular matrix, and actin cytoskeleton functions at both stages, while upregulated DEGs were enriched in eye development functions at 35 dpf. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed enrichment of downregulated DEGs in focal adhesion and extracellular matrix (ECM)-receptor interaction pathways at both stages. Neuronal development DEGs were mainly downregulated at both stages, while synaptic signaling DEGs were upregulated at 35 dpf. Crossing cdkl5−/− mutants with the Hb9:GFP transgenic line showed fewer motor neuron cells with shorter axons compared to the wild type, which may explain the impaired motor phenotype observed in zebrafish and CDD patients. Moreover, we identified key downregulated DEGs related to cartilage development at both stages and bone development at 35 dpf, potentially explaining the skeletal defects seen in zebrafish and CDD individuals. In conclusion, Cdkl5 loss in zebrafish leads to dysregulation of genes involved in CDKL5-associated functions in mammals, providing new insights into its less studied functions and phenotypes.
- Adaptation and validation of the perceived restorativeness scale (PRS) for the portuguese population: a study on the assessment of the restorative effect of environmentsPublication . Sousa, Cátia; Silva Fernandes, Maria Jacinta; Encarnação, Tiago; Gonçalves, GabrielaThe relationship between natural environments and psychological well-being has gained increasing attention in environmental and health sciences. However, there is still a lack of robust quantitative instruments to assess the restorative potential of different environments. This study aimed to adapt and validate the Portuguese version of the Perceived Restorativeness Scale (PRS), an instrument based on Attention Restoration Theory that evaluates the perceived restorative qualities of environments. In Study 1, exploratory and confirmatory factor analyses were conducted on data from 410 participants. The results supported a refined 20-item version of the scale, comprising four factors—being away, fascination, compatibility, and legibility—with good internal consistency and acceptable model fit. Measurement invariance analysis confirmed configural, metric, and scalar invariance across gender. In Study 2, a separate sample of 212 participants completed the PRS along with additional validated measures: the Sublime Emotion toward Nature Scale (SEN), an aesthetic evaluation of landscapes, and the Positive and Negative Affect Schedule (PANAS). The PRS showed strong convergent and discriminant validity and significantly predicted restorative outcomes. These findings support the psychometric adequacy of the Portuguese PRS and its relevance as a valid tool for assessing perceived restorativeness in both natural and built environments. The scale may inform future research and public policies aimed at designing spaces that promote psychological restoration and mental well-being.
- Handling the heat: ocean acidification mitigates the effects of marine heatwaves on Posidonia oceanica seedlingsPublication . Pazzaglia, Jessica; Marín-Guirao, Lazaro; Ambrosino, Luca; Pes, Katia; Costa, Monya; Barrote, Isabel; Silva, João; Procaccini, Gabriele; Crysten Blaby-HaasOcean acidification and marine heatwaves are key drivers of marine ecosystem changes that can interact with one another and influence marine organisms. Seagrasses, including the long-lived Posidonia oceanica that is endemic to the Mediterranean Sea, are widely distributed along coastal habitats, forming highly valuable underwater meadows. The germination and survival of the early life stages of P. oceanica are strongly affected by environmental changes. To assess the impact of warming and acidification on its future, we conducted a multifactorial experiment in which P. oceanica seedlings were grown under ocean acidification conditions for 6 months and then exposed to a seawater warming event. Seedling performance was investigated by analysing photo-physiology, antioxidant capacity, energetic metabolism, and transcriptomic profiles. A weighted gene correlation network analysis was used to integrate phenotypic plant traits with transcriptomic results to identify central genes involved in plant responses to ocean acidification and temperature exposure. Results demonstrated that prolonged ocean acidification exposure enhances P. oceanica seedling resilience to marine heatwaves. Specifically, seedlings regulated their antioxidant systems and transcriptomic machinery to better cope with thermal stress. Under current CO2 concentrations, elevated temperatures induced stress in P. oceanica seedlings, impacting photosynthesis and respiration. However, ocean acidification could mitigate the impact of warming in the future, enhancing the resilience to global stressors of P. oceanica.
- Improving trust in online reviews: a machine learning approach to detecting artificial intelligence-generated reviewsPublication . Ana Marta Santos; Antonio, NunoIn the hotel industry, social reputation is critical. Consumers increasingly rely on online reviews for accommodation decisions, making Artificial Intelligence (AI) generated fraudulent reviews a significant threat. Distinguishing between genuine and AI-generated reviews is essential for hotels to maintain credibility. This study creates a unique dataset of AI-generated reviews and combines vectorization methods with text-based features to build a Machine Learning model for identifying nongenuine reviews. Results show that incorporating text-based features significantly improves detection accuracy, and simpler vectorization methods can be effective for simpler datasets. This study contributes to academia by providing a novel methodology and publicly available dataset for further research, and to the hotel industry by enhancing credibility and consumer trust through better review filtering.