Sapientia
UAlg Scientific Repository
About Sapientia
SAPIENTIA brings together all scientific publications produced by teachers, researchers, and students (theses and dissertations) from the University of Algarve and cooperating entities (ULSALG-Unidade Local de Saúde do Algarve and Ciência Viva network centers in the Algarve) and aims to maximize their visibility, ensure easy access to this collection, improve the public impact of the scientific activity of the University and other entities, as well as ensure the preservation of their memories.
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Recent Submissions
STE(A)M learning ecologies and creativity: a typology of open schooling projects based on stakeholder and learner engagement
Publication . Hovardas, Tasos; Vakkou, Kyriaki; Arampatzi, Konstantina; Zacharia, Zacharias; Tasiopoulou, Evita; Mavromanolakis, Georgios; Liakopoulos, Vasilis; Koulouris, Pavlos; Sotiriou, Sofoklis; Cherouvis, Stephanos; Stekić, Katarina; Barella, Patricia; Deely, Mary; Mentini, Laura; Chatzidaki, Eleni; Giannakos, Michail; Tiemann, Ruediger; Horchemer, Melissa; Muscat, Mario; Veiga-Pires, Cristina
Despite the considerable funding of open schooling projects from the EU, relevant publications have been scarce. We present an analysis of open schooling initiatives launched within the frame of the STE(A)M Learning Ecologies – SLEs Project. SLEs offer opportunities to promote creativity of both learners and stakeholders engaged through innovative pedagogical design and the delivery of original learning artefacts (learning products). We gathered and analyzed several forms of data reflecting learner and stakeholder engagement associated with these initiatives. They included two templates completed with stakeholder input (participatory pedagogical design template; participatory scenario development template), learning products delivered by students in each SLE, interviews with stakeholders and responses to open-ended questionnaire items. Our data analysis revealed four types of SLEs: (1) Learner-experience oriented, (2) Master-product oriented, (3) End-user oriented, and (4) Citizen-science oriented. We present similarities and differences of the various types of SLE with regard to stakeholder synthesis (diversity), learning objectives, female participation, career opportunities, their potential for transformative change, challenges encountered, and sustainability aspects. Based on the typology of SLEs and their characteristics, we identified a series of recommendations for future research and policy to optimize investment in and impact of open schooling projects. These include a focus on small wins to scale up SLEs, distributed leadership to empower teachers and increase availability of learning resources and learner support, and using learning products to decentralize formative assessment in SLEs and promote constructive stakeholder dialogue.
Effect of biochar binding on dielectric properties of color catcher sheets
Publication . Kovalchuk, O. V.; Prochazkova, J.; Kovalchuk, T. M.; Volokh, L. V.; Oleinikova, I. V.; Mariano, José; Safarik, I.; Kopansk, P.
The dielectric properties in the frequency range of 102 to 106 Hz and at the temperatures of 30 to 60 °C of 0.4 mm thick color catcher sheets (nonwoven textile with ion exchange properties) both in the native state and with bound biochar were investigated using the oscilloscope method. The sample dimensions were 1×1 cm. To assess the influence of the sample thickness, samples with several (maximum 4) layers were used together with one-layer textile. It was shown that, unlike the data obtained by us earlier, the dielectric properties of the nonwoven textile without additives are caused by near-electrode processes. It was demonstrated as well that in this case, the dispersion of the frequency dependences of inverse resistance (analog of the imaginary component of complex dielectric permittivity) with respect to capacitance (analog of the real component of complex dielectric permittivity) corresponds to the Debye dispersion. Using the obtained results, the dielectric relaxation time (2.4·10–5 s) and the thickness of the near-electrode layer (1.5 μm) were estimated. Measurements at different temperatures and with several layers of the native textile demonstrated that the parameters of this relaxation process do not depend on both the sample thickness and the temperature. It was found that the sample resistance decreased by 3 orders of magnitude on average in the presence of biochar bound to the textile. In this case, the temperature dependence of the inverse resistance (analog of conductivity for uniform and continuous bodies) obeyed the Arrhenius law. The activation energy of the temperature dependence of the inverse resistance was 0.37 eV, which is greater than the similar value obtained in our work of 2024.
Impact of seasons on industrial cultivation of Limnospira platensis (Spirulina): a year-round case study on biomass, phycocyanin, and protein productivity in Portugal
Publication . Guerra, Inês; Torres, Cátia; Cardoso, Helena; Pereira, Hugo; Trovão, Mafalda; Rodrigues, Alexandre M. C.; Varela, João
Spirulina is the most commercially produced biomass, among microalgae and cyanobacteria, with extensive applications across food, feed, nutraceutical and biotechnological sectors. While Spirulina cultivation is wellcharacterized at laboratorial and small-scale production, critical knowledge gaps remain regarding industrialscale production in temperate climates. Specifically, there is a lack of robust empirical data on how seasonal environmental fluctuations affect year-round productivity and the maintenance of consistent biomass quality (protein, phycocyanin content) under large-scale operational constraints. This study evaluates the year-round industrial production of Limnospira platensis in large-scale (1000 m2 and 4000 m2 ) raceway reactors at Allmicroalgae - Natural Products S.A., Portugal. Biomass productivity as well as protein and phycocyanin contents across different seasons and throughout the day were assessed. The influence of environmental factors such as temperature and solar radiation on productivity and biomass composition was also analyzed. Industrially grown Spirulina reached an average annual productivity of 5.1–5.6 g.m− 2 .d− 1 . Seasonal variation revealed a winter productivity decline higher than 60 %, compared to peak yields of 7.5–7.6 g.m− 2 .d− 1 from April to September. Protein content remained consistent year-round between 58.4 and 64.7 %, whereas phycocyanin content presented strong solar radiation dependence, peaking at 15.2 % in summer and decreasing to 10.4 % in winter. Furthermore, an analysis throughout the day identified an optimal harvesting window between midday and sunset to maximize phycocyanin levels. These findings validate the industrial feasibility of year-round Spirulina cultivation in temperate climates and provide seasonal productivity forecasting and harvest timing optimization, towards protein consistency and phycocyanin yield optimization.
AI-driven conservation of the endangered twisted yew (Taxus contorta Griff.) in the western himalaya
Publication . Din, Salahud; Ali, Haidar; Panagopoulos, Thomas; Alam, Jan; Malik, Saira; Sher, Hassan
Conserving the threatened West Himalayan endemic T. contorta (Taxaceae) is critical due to extinction risks from skewed male- or female-only populations. This study employs ChatGPT-driven artificial intelligence (AI) analysis for textual synthesis and preliminary hypothesis generation to identify favorable propagation sites for T. contorta within the Swat district of Pakistan. Over three years (2019–2021), eleven male- or female-only populations of T. contorta were surveyed. Environmental data from NASA POWER were analyzed using ChatGPT 3.5 to predict suitable propagation sites, which were then mapped in Google Earth Pro. PCA and hierarchical clustering were applied to identify key environmental variables. Out of 63 generated points, 58 were accurately located in Swat with 92% geographic accuracy, while species-specific general knowledge accuracy was 100%. All points fell within the pre-established T. contorta spatial range in Pakistan, with 21 unique sites meeting optimal conditions. Field surveys confirmed 16 new populations. These findings underscore the promising role of AI-driven analysis in conservation planning by identifying and supporting habitat restoration efforts. A bidirectional integration of AI and SDM, combined with remote sensing technologies, represents a novel approach for the effective conservation of endangered plant species.
Special issue “medical value of metal complexes and plant-derived compounds: biological evaluation, health effects, challenges, and future opportunities”
Publication . Ścibior, Agnieszka; Aureliano, Manuel; Llopis, Juan
This Special Issue (SI), titled “Medical Value of Metal Complexes and Plant-Derived Compounds: Biological Evaluation, Health Effects, Challenges, and Future Opportunities”, aims to include reports updating our knowledge about the effects of exposure to prevalent heavy metals in the environment, which adversely affect animal and human health. It also focuses on certain natural plant bioactive compounds with multidirectional biological properties, which can effectively alleviate the toxicity of highly hazardous heavy metals and minimize the negative effects of veterinary drugs widely used in the treatment of food-producing animals, on consumer health. It should be emphasized that substances of plant origin are a very interesting research material both in terms of the diversity of the chemical structures of isolated compounds and their possible therapeutic properties [1,2]. For a long time, there has been considerable interest in biologically active compounds of plant origin due to their potential in preventing the toxic effects of xenobiotics [3]. This is a very important and currently relevant trend associated with the search for effective strategies based on natural origin substances aimed at preventing the harmful effects of xenobiotics or mitigating their toxic effects.