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- Empowering the creative design process through LLM-based support toolsPublication . Rodrigues, Ana; Cabral, Diogo; Campos, Pedro; Rodrigues, Ana; Campos, Pedro Filipe Pereira ; Campos, PedroCreative professionals (such as designers) have begun applying gen erative artificial intelligence (GenAI) models to their workflows, from text to image production. This practical adoption has been explored in human-computer interaction (HCI), which guides the incorporation of these models into creative design processes. While HCI research explores GenAI, an underlying wave of research is emerging, incorpor ating these models into Creativity Support Tools (CSTs). Our work aims to articulate the role of GenAI in supporting design creativity, an area that still requires research. This knowledge is essential for guiding the development of new CSTs. We contribute to this knowledge by devel oping an LLM-based CST with two interactive visualization interfaces (idea generation and evaluation). Through an empirical study with 18 participants (professionals and advanced design students) with design backgrounds, we demonstrated SAIESE’s potential to facilitate diver gent and convergent thinking. We also identify opportunities and challenges of incorporating AI into the creative design process. Our results highlight the role and use of AI at each stage.
- The oldest plant fossils from Tenerife Island? The case of the Pliocene lava tree moulds from San Roque, La Laguna, SpainPublication . Góis-Marques, C. A.; Velasco-Flores, M. C.; Martín-Luis, M. C.; Castillo-Ruiz, C.; Góis-Marques, Carlos A.provide interesting palaeoecological and volcanological data. In the volcanic Macaronesian Islands, these fossils are known since the 19 th century but rarely mentioned in the literature, despite their potential to reveal the past presence of trees and forested ecosystems. One mention to plant moulds associated to the Anaga basalts was known, but further details were never published. Here, we describe and illustrate for the first time lava tree moulds preserved within the Pliocene Anaga shield volcano (4.89 to 3.95 Ma) a’a lava flow. The size and stem habit indicate that these belonged to phanerophytes, implying the presence of a forest ecosystem during the Pliocene of Tenerife. When compared to the palaeobotanical record of Tenerife Island, these fossils are, so far, the oldest known published plant fossils from this island. Unfortunately, due to total combustion of the wood, taxa identification is not possible. Despite this, the locality should be further assessed as a potential geosite or other form of conservation for the Canary Islands’ palaeontological heritage. Further prospection in Mio-Pleistocene Anaga shield volcano will certainly yield new palaeobotanical data for Tenerife and the Canary Islands.
- Artificial intelligence advancements and US nuclear energy deregulation are drivers of the short-term market returns of nuclear firms?Publication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno; Martins, António Miguel; Albuquerque, Bruno; Sardinha, LuísThis study examines the short-term market effect of the US nuclear market deregulation an nouncements in an environment of increasing investments in AI, which demand clean energy. By employing an event study methodology, our results suggest that worldwide nuclear energy firms experienced a positive and statistically significant impact on stock prices for the announcements of investments in AI and nuclear market deregulation, particularly among larger firms and those located in the US. These findings support the cash flow hypothesis for AI and the deregulation hypothesis for the nuclear market. Practical implications of our findings are provided.
- The impact of wildfires on US insurance firms: evidence for the costliest wildfire in CaliforniaPublication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno; Martins, António Miguel; Albuquerque, Bruno; Sardinha, LuísThis research study the short-term effect of the costliest wildfire in California (January 2025) on the US insurance industry. Employing an event study, we find a negative impact for Property & Casualty Insurance firms. This result agrees with damage hypothesis or claim effect, which argues that damage caused by catastrophic events results in a reduction of insurer market value due to insufficient ex ante premium to absorb the damage claims. Our study also shows that the level of loss, premiums, underwriting exposure, profitability, and leverage are significant determinants in the magnitude of the insurer’s stock market reaction.
- Nutrient deprivation stimulates soluble extracellular polymeric substances: physiological and biochemical responses in the cyanobacterium Cyanocohniella rudolphiaPublication . Rodrigues, Filipa; Mendonça, Ivana; Faria, Marisa; Mougin, Karine; Gómez Pinchetti, Juan Luis; Ferreira, Artur; Cordeiro, Nereida; Gonçalves Rodrigues, Ana Filipa; Silva Mendonça, Ivana Rita da; Faria, Marisa Camacho Gonçalves; cordeiro, nereidaThe effect of macro- and micronutrient deprivation on the cyanobacterium Cyanocohniella rudolphia (BEA 0786B) over 180 days (without medium renewal) was evaluated to intensify the production of soluble extracellular polymeric substances (S-EPS). Growth, pH, cell-free medium viscosity, S-EPS content (phenol‑sulfuric acid assay), Alcian Blue staining, and biochemical/structural markers were monitored to assess EPS release and extracellular matrix dynamics. Progressive nutrient depletion induced a shift from biomass growth toward extracellular-matrix investment. Microcolony formation observed around day 45 preceded a sustained high- production phase, with pronounced matrix densification evident by approximately day 75. Apparent viscosity increased in parallel with S-EPS accumulation and showed a strong correlation with extracellular carbohydrate concentration (R 2 = 0.86), supporting its use as an operational, non-destructive proxy for S-EPS. Alcian Blue staining qualitatively confirmed the presence of acidic polysaccharides. Quantitatively, S-EPS concentrations increased from 0.1 to 0.8 g L 1 , accompanied by an increase in apparent viscosity from 24.7 to 34.7 mPa⋅s. Morphological and spectroscopic analyses indicated a predominantly carbohydrate-rich extracellular matrix with an increasing protein contribution over time. As an exploratory proof of concept, unprocessed S-EPS present in the spent culture medium enabled LAP- initiated photochemical formation of Au and Ag nanoparticles at 365 nm, with S-EPS acting as a stabilising and co-reducing matrix and conferring pH-responsive optical behaviour. This indicates a practical route toward integration into EPS-rich matrices to engineer stimuli-responsive coatings and biomaterials. Overall, this study demonstrates that prolonged nutrient deprivation without medium renewal is an effective strategy to intensify S- EPS accumulation in C. rudolphia and that apparent viscosity provides a practical in-process parameter for monitoring production and supporting direct valorisation of spent culture medium in saline bioprocesses.
- Towards scalable production of bound extracellular polymeric substances (B-EPS): autoclave hydrothermal extraction coupled with solvent-free ultrafiltrationPublication . Mendonça, Ivana; Rodrigues, Filipa; Marisa Faria; Gómez Pinchetti, Juan L.; Ferreira, Artur; Cordeiro, Nereida; Silva Mendonça, Ivana Rita da; Gonçalves Rodrigues, Ana Filipa; Faria, Marisa Camacho Gonçalves; cordeiro, nereidaBound extracellular polymeric substances (B-EPS) are extracellular polysaccharides tightly attached to cyanobacterial and microalgal cell surfaces, representing a high-value class of biopolymers with industrial potential. Selective extraction is technically challenging due to strong adhesion to the cell wall and poten tial co-extraction of soluble EPS. Conventional methods can be chemically aggressive and may involve high energy and/or solvent inputs, making solvent-free extraction routes desirable. In this work, four hydrothermal extraction techniques (reflux, autoclave, ultrasonic bath, and microwave) were evaluated for their ability to recover B-EPS from the marine cyanobacterium Chroococcus submarinus (BEA 1200B), followed by a harmonised ultrafiltration step. Each method was assessed for extraction efficiency and its impact on bulk descriptors (inorganic carry-over, ATR-FTIR, zeta potential, and thermal profiles) and mor phology. Among the methods tested, autoclave extraction demonstrated the highest performance, yield ing up to 2.5 times more B-EPS than the other methods and showing reduced inorganic carry-over after purification. Across all methods, the purified B-EPS fractions exhibited broadly comparable bulk profiles under the applied analytics. Response Surface Methodology (RSM) applied to the autoclave system ident ified temperature and extraction time as key variables; optimal conditions (biomass-to-solvent ratio 1:20 (w/v), 130 °C, 16 min) enabled >90% recovery. Coupling autoclave extraction with solvent-free ultrafiltra tion avoids solvent precipitation and the use of hazardous reagents, enabling desalting and removal of low-molecular-weight components. Using a photosynthetic marine strain supports seawater cultivation and biogenic CO2 uptake, aligning the workflow with carbon-mitigation goals.
- On taxonomy construction by recursive generative logicPublication . Constantine, Larry LeRoyAbstract A potentially novel formal, systematic approach for theory-informed taxonomy construction is presented based on maximizing qualitative differences among defined taxa through generative logic. A recursive-dialectic taxonomy is a special form of classification constructed through recursive application of a logical function based on narrowly defined formal operations of absolute antithesis and absolute synthesis. Recursive-dialectic taxonomies have features that may offer advantages from both theoretical and applied perspectives across many different disciplines. The generative approach ensures that taxa are maximally conceptually distinct within the underlying theoretical framework from which the taxonomy is constructed. Such a taxonomy is also quantitatively well-defined, as it maps straightforwardly into a k -simplex closed property space in which geometrically defined taxonomic differentiae and typological dimensions are derived from and conceptually linked directly to the underlying theoretical basis of the taxonomy. The resulting closed property space is an Aitchison space that can be treated as compositional data for purposes of statistical analysis in empirical research based on the taxonomy. The relationship of the taxonomic method to Belnap–Dunn logic of first-degree entailment is noted. An example of application of the method to construction of a taxonomy of human socio-cultural systems based on social coordination theory is illustrated.
- Selective contractionPublication . Garapa, Marco; Eduardo Fermé; Reis, Maurício D. L.; Garapa, Marco; Fermé, Eduardo; Reis, MaurícioAbstract Selective revision operators are well-known non-prioritized revision operators that allow for the acceptance of only part of the new information while rejecting the rest. In this paper, we introduce their contraction counterparts, which we refer to as selective contraction operators. These operators enable the removal of only part of the input information. As such, selective contractions can be viewed as a method for removing some of the beliefs that support the input belief without eliminating the belief itself. In this sense, selective contraction operators allow for a weakening of the input belief’s strength without discarding it. We provide representation theorems for various classes of selective contraction operators.
- The role of mental toughness and academic satisfaction in suppressing first-year students’ intentions to dropout of universityPublication . Rodrigues, Nuno; Rebelo, Teresa; Delgado Rodríguez, Naira; Rodrigues, NunoAbstract The urgent need to reduce the substantial and persistent incidence of higher education dropout, especially during the first academic year, calls for further research to identify the core predictors of students’ withdrawal intentions and actual behaviors. Specifically, more research is needed to assess whether and how students’ personal resources and academic attitudes interplay in shaping this phenomenon. This study addresses these questions by examining the unexplored joint role of students’ mental toughness and academic satisfaction in counteracting their intention to leave university at the end of the first year. Data from a sample of 187 first-year undergraduates at a non-residential public university, collected at three measurement points, supported the validity of both variables in predicting dropout intentions, after controlling for the effects of academic performance. The results also indicated that the effect of mental toughness in suppressing dropout intentions does not occur when students are dissatisfied with the university. The main implications of these findings are presented and discussed.
- Biorefinery of red macroalgae from Madeira archipelago for value-added productsPublication . Nunes, Nuno; Vieira, Ana C.; Odenthal, Kilian; Miguel Â. A. Pinheiro de Carvalho; Nunes, Nuno; Leal Vieira, Ana Carolina; Odenthal, Kilian; Almeida Pinheiro de Carvalho, Miguel AngeloAbstract Red macroalgae represent an underexplored yet promising resource due to their rich composition in proteins, pigments, and bioactive compounds with potential uses in nutraceutical, pharmaceutical, and agricultural industries. However, despite their abundance in coastal regions many species remain neglected and the development of efficient extraction and valorisation methods is still limited. This work assesses the optimization of protein and phycoerythrin extraction from three abundant red macroalgae species, Grateloupia lanceola , Asparagopsis taxiformis , and Nemalion elminthoides collected in Madeira island. Its major objective was to study a new biorefinery concept. The response surface methodology (RSM) results indicate that G. lanceola , harvested from offshore fish farms, exhibits the highest concentrations of both protein (2967 mg L −1 ) and phycoerythrin (212 mg L −1 ) when subjected to specific extraction parameters such as higher biomass weight (400 g) and increased number of cycles (18) using the Solid–Liquid Extraction system. In contrast, A. taxiformis and N. elminthoides demonstrated varied extraction patterns, with A. taxiformis producing substantial protein concentrations (328 mg L −1 ) but lower phycoerythrin yields (11 mg L −1 ). Sequential biorefinery methods were also employed to obtain bioactive compounds, and polysaccharides extracts. G. lanceola yields the highest concentration of soluble proteins (6.25 ± 0.59 g (100 g) −1 dw) and polysaccharides (11.13 ± 4.85 g (100 g) −1 dw), while N. elminthoides showed superior bioactive extract concentration (11.81 ± 0.31 g (100 g) −1 dw). The phenolic content in bioactive extracts has also been assessed using the Folin Ciocalteu method, finding a significant variation in total phenolic content among the species (1.38 ± 0.22 and 5.16 ± 0.06 mg GAE g −1 dw). The chromatographic analysis, formed by a Waters HPLC system and a photodiode array detector (Waters 2996) allowed to detect phenolic compounds within the bioactive extract, which include protocatechuic acid, hydroxybenzoic acid, epicatechin, p-coumaric acid and ferulic acid. Furthermore, the agronomic potential of the biorefinery residues was explored, revealing high nitrogen and phosphorus contents in liquid and solid residues, suggesting their potential to be used as biofertilizers. These findings contribute to the development of sustainable extraction processes for bioactive compounds from red macroalgae, enhancing the efficiency of biorefinery strategies and promoting the marine biomass valorization.