Sapientia
UAlg Scientific Repository
About Sapientia
The SAPIENTIA repository gathers an exhaustive set of Algarve University's (UAlg) teachers and researchers scientific publications with an express goal of maximising its visibility, ensure easy and universal access and amelliorate the overall public impact of the university scientific endeavors, as well as the ongoing preservation of its memory.
Recent Submissions
Eco-innovative aquafeeds biofortified with asparagopsis taxiformis to improve the resilience of farmed white seabream (Diplodus sargus) to marine heatwave events
Publication . Marmelo, Isa; Lourenço-Marques, Cátia; Silva, Iris A.L.; Soares, Florbela; Pousão-Ferreira, Pedro; Mata, Leonardo; Marques, António; Diniz, Mário Sousa; Maulvault, Ana Luísa
Extreme weather events, like marine heatwaves (MHWs), are becoming more frequent and severe due to climate change, posing several challenges to marine ecosystems and their services. As disease outbreaks are often prompted by these acute phenomena, it is essential to develop ecoinnovative strategies that can efficiently improve farmed fish resilience, especially under suboptimal rearing conditions, thereby ensuring a sustainable aquaculture production. This study aimed to unveil farmed juvenile white seabream ( Diplodus sargus, , 28.50 +/- 1.10 g weight, n = 150) immune and antioxidant responses under a category II MHW in the Mediterranean Sea (+4 degrees C, 8 days of temperature increase plus 15 days of plateau at the peak temperature) and to investigate whether a 30 days period of prophylactic biofortification with Asparagopsis taxiformis (1.5 %, 3 % and 6 %) enhanced fish resilience to these extreme events. Several biomarkers from different organization levels (individual, cellular, biochemical and molecular) were assessed upon 30 days of biofortification (T30), exposure (after 8 days of temperature increase + 15 days at peak temperature, T53) and recovery (8 days of temperature decrease, T61) from the MHW. Results showed that MHW negatively affected the fish physiological status and overall wellbeing, decreasing specific growth rate (SGR) and haematocrit (Ht) and increasing erythrocyte nuclear abnormalities (ENAs) and lipid peroxidation (LPO). These adverse effects were alleviated through biofortification with A. taxiformis. . Seaweed inclusion at 1.5 % was the most effective dose to minimize the severity of MHW effects, significantly improving immune responses of D. sargus (i.e. increased levels of immunoglobulin M, peroxidase activity and lysozyme expression) and modulating antioxidant responses (i.e. decreased LPO, catalase and glutathione S-transferase activity). These findings confirm that A. taxiformis is a functional ingredient of added value to the aquaculture industry, as its inclusion in marine fish diets can beneficially modulate fish immunity and resilience under optimal and adverse rearing conditions.
Strategy combining mammalian fats with supplementation of pungent spices in aquafeeds, to mitigate negative impacts of fish oil replacement in fish performance, fillet quality and hepatic condition of gilthead seabream (Sparus aurata)
Publication . Ruiz, Alberto; Gisbert, Enric; Estevez, Alicia; Reyes-López, Felipe E.; Vallejos-Vidal, Eva; Tort, Lluís; Dias, Jorge; Engrola, Sofia; Magalhães, Sara; Aires, Tiago; Morais, Sofia
The replacement of fish oil (FO) in aquafeeds usually leads to imbalances in the dietary content of n-3 and n-6 polyunsaturated fatty acids (PUFA), with negative consequences for fish performance, health, and fillet quality. Animal-rendered fats are an alternative lipid source high in saturated fatty acids, potentially sparing n-3 PUFA from oxidation, and with lower n-6 PUFA contents than plant-based oils, especially in the case of mammalian fats (MF). Hence, this work assessed the effect of replacing 45% FO by MF (negative control, NC) compared to a diet containing only FO (positive control, PC) in gilthead seabream (Sparus aurata, initial body weight: 85 ± 4 g, mean ± standard deviation) at low water temperature. In addition, we studied the effect of supplementing the NC diet with a combination of pungent spices with hypolipidemic and anti-inflammatory properties at three inclusion levels: 0.05 (SPICY0.05%), 0.1 (SPICY0.1%), and 0.15% (SPICY0.15%). At the end of the trial (112 days), FO substitution by MF led to poorer fish performance in terms of body weight (BW), specific growth rate (SGR), feed conversion ratio (FCR), and protein efficiency ratio (PER). Supplementation of the NC diet with spices numerically improved SGR, FCR and PER at all inclusion levels (non-significantly different from the PC group), being FCR and PER significantly different from the NC group in the SPICY0.1% and SPICY0.15% treatments. A remarkable increase in lipid level was observed in fillets of fish fed the NC diet, but was fully counteracted by spice supplementation, especially in fish fed the SPICY0.15% diet. A lower fat accumulation was also found in the liver of fish fed the SPICY0.1% and SPICY0.15% diets, with respect to the PC and NC groups. The fillets' fatty acid profile mostly reflected the diet composition, but the SPICY0.15% diet modified it in an inverse direction to that observed in the NC, to more closely resemble the profile of fish fed the PC diet. In particular, the SPICY0.15% diet reduced fillet levels of MUFA, linoleic and linolenic acids, and increased n-3 LC-PUFA (including EPA and DHA), compared to the NC. A microarray-based transcriptomic analysis revealed a better hepatic health status, as indicated by different biological processes associated to immunity. Overall, supplementation with the combination of pungent spices at 0.15% enabled the incorporation of alternative lipid sources, such as MF, in aquafeeds without significantly compromising growth and feeding performance, liver health, and quality of the edible product.
Sleep quality and falls in middle-aged and older adults: ELSI-Brazil study middleaged middle aged adults ELSIBrazil ELSI Brazil
Publication . Santos, André Pereira dos; Cordeiro, Jéssica Fernanda Correa; Abdalla, Pedro Pugliesi; Bohn, Lucimere; Sebastião, Emerson; Silva, Leonardo Santos Lopes da; Tasinafo Júnior, Márcio Fernando; Venturini, Ana Cláudia Rossini; Andaki, Alynne Christian Ribeiro; Mendes, Edmar Lacerda; Marcos-Pardo, Pablo Jorge; Mota, Jorge; Machado, Dalmo Roberto Lopes; Lopes Machado, Dalmo Roberto
Objective: To verify the association between low self-reported sleep quality (LSQ) and fall in middle-aged and older adults every half-decade of life. Method: A cross-sectional study was conducted using data from the first wave (2015–2016) of the Brazilian Longitudinal Study of Aging (ELSI-Brazil), which is nationally representative. The sample consisted of 8,950 participants who were allocated into eight age groups: 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84, and ≥ 85 years. The questionnaires used included self-reported sleep quality and the International Physical Activity Questionnaire short version. Fisher’s exact test followed by binary logistic regression analysis was performed to identify the odds ratio of sleep quality for fall occurrence, controlled for confounding variables. Results: Individuals aged 50–105 years (63.6 ± 10.2 years), 57.0% females and 43.0% males, participated in this study. Overall, 21.5% of participants experienced at least one fall. The relative frequency of participants classified as having high or LSQ remained constant across each half-decade of life. The LSQ exhibited a statistically significant OR (p < 0.05) for falls across age groups up to 84, even after accounting for confounding variables. Conclusion: LSQ is significantly associated with an increased occurrence of fall in adults aged >50 years, but not for ≥ 85 years regardless of sex and physical activity level.
Symbiotic endolithic microbes reduce host vulnerability to an unprecedented heatwave
Publication . Zardi, Gerardo; Monsinjon, Jonathan R.; Seuront, Laurent; Spilmont, Nicolas; McQuaid, Christopher D.; Nicastro, Katy
Heatwaves are increasingly severe and frequent, posing significant threats to ecosystems and human well-being. Characterised by high thermal variability, intertidal communities are particularly vulnerable to heat stress. Microbial endolithic communities that are found in marine calcifying organisms have been shown to induce shell erosion that alters shell surface colour, lowering body temperatures and increasing survival rates. Here, we investigate how the symbiotic relationship between endolithic microbes and the blue intertidal mussel Mytilus edulis mitigates thermal stress during the unprecedented 2022 atmospheric heatwave in the English Channel. Microbial infestation of the shell significantly enhanced mussel survival, particularly higher on the shore where thermal stress was greater. Using data from biomimetic temperature loggers, we predicted the expected thermal buffer and observed differences up to 3.2 °C between individuals with and without symbionts under the known conditions of the heat wave-induced mortality event. The ecological implications extend beyond individual mussels, affecting the reef-building capacity of mussels, with potential cascading effects for local biodiversity, carbon sequestration, and coastal defence. These findings emphasize the importance of understanding small-scale biotic interactions during extreme climate events and provide insights into the dynamic nature of the endolith-mussel symbiosis along a parasitic-mutualistic continuum influenced by abiotic factors.
Imperialism, empowerment, and support for sustainable tourism: Can residents become empowered through an imperialistic tourism development model?
Publication . Moreira dos Santos, Edson Redy; Nobre Pereira, Luis; Pinto, Patrícia; Boley, B. Bynum; Ribeiro, Manuel Alector
Resident empowerment is an effective tool that contributes to the sustainable development of tourism. However, in many low-income countries, tourism is usually implemented through an imperialist tourism development model, questioning the sector's true intentions for this type of development. Within this backdrop, this study aims to investigate how, under such conditions, residents' perception of imperialism is associated with residents' perceptions of empowerment and to what extent these perceptions influence their support for sustainable tourism development. To better understand these relationships, Weber's Theory of Formal Substantive Rationality and Institutional Theory were employed. This study surveyed a representative sample of 341 residents on the island of Sal, Cape Verde in 2022. Overall, results illustrate that residents' perceptions of imperialism do not affect their perceptions of empowerment, rejecting most of the research hypotheses. Theoretical and practical implications highlight that within an imperialistic tourism development model, there is not relationship between imperialims and empowerment. tourism.