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- Advances on the Synthesis, Reactivity, and Biological Properties of 4H‐Thiochromen‐4‐(thio)one DerivativesPublication . Santos, Clementina M.M.; Silva, ArturThe aim of the present review is to provide a systematic survey on the recent advancements in the chemical synthesis of thiochromones, thiochromanones, the less explored thiochromene-4-thiones and some analogs. These compounds are used as versatile building blocks in the synthesis of other complex and polycyclic heterocyclic analogs. Highlights on biological and photophysical properties of these thio derivatives are also included and discussed. It covers the literature from 2014 to 2024, in more than 170 publications.
- Artificial intelligence tools for project management: A knowledge-based perspectivePublication . Almeida, Pedro M.; Fernandes, Gabriela; Santos, José M.R.C.A.The rapid evolution of artificial intelligence is pressing the need to understand how organisations can integrate it into namely project management to enhance performance and outcomes. Through a systematic literature review, this paper explores artificial intelligence's potential use in project management. The thematic analysis of relevant literature identified key project management knowledge areas, such as integration, scope, communication, risk and stakeholder management, were as domains where artificial intelligence holds significant potential. The study further investigates the relationship between these knowledge areas and the most suitable types of artificial intelligence tools, such as generative artificial intelligence, and machine learning algorithms for optimisation and automation, based on the dominant knowledge type each knowledge area requires, namely formal, data-driven, or tacit knowledge. Based on the main findings, the study proposes a conceptual framework for the integration of artificial intelligence tools in project management, offering valuable insights for scholars and practitioners. Moreover, guidelines for future research to accelerate the wide adoption of artificial intelligence in the field are proposed.
- Bioaccessibility Performance of Phenolic Compounds from Red Fruits During Simulated Gastrointestinal Digestion and Colonic FermentationPublication . Bortolini, Débora Gonçalves; Barros, Lillian; Maciel, Giselle Maria; Peralta, Rosane M.; Corrêa, Vanesa G.; Finimundy, Tiane Cristine; Haminiuk, Charles Windson IsidoroRed fruits are rich in phenolic compounds, particularly anthocyanins, which contribute to their vibrant colors and health benefits. However, anthocyanins are chemically sensitive during digestion, which affects their bioaccessibility. This study evaluated the impact of simulated gastrointestinal digestion on whole red fruits (oral, gastric, intestinal, and colonic phases). Total phenolic content (TPC) ranged from 8.60−50.41 mg GAE/g DW, total flavonoid content (TFC) from 1.66−10.67 mg CAT/g DW, and total monomeric anthocyanins (TMA) from 0.54−1.28 mg CYA/g DW. Antioxidant activity strongly correlated with TPC (r ≥ 0.91). High-phenolic fruits showed lower bioaccessibility compared with low-phenolic ones. HPLC-DAD-ESI/MSn identified glycosylated anthocyanins, which were highly sensitive; jaboticaba anthocyanins were nonbioaccessible, while 51.83% remained bioaccessible in raspberries. Colonic fermentation further reduced TPC and TFC, and anthocyanins were entirely degraded. These results highlight the need for innovative delivery systems to improve anthocyanin bioaccessibility and functional benefits.
- Bioactive and Phenolic Profiles in Pinus pinaster Bark: A Comparative Study of Microwave and Ultrasound Extraction MethodsPublication . Barros, Diana; Alonso-Esteban, José Ignacio; Finimundy, Tiane C.; Pereira, Carla; Vaz, Josiana A.; Pereira-Pinto, Ricardo; Fernandes, Élia; Pires, Preciosa; Santos, Joana; Barros, Lillian; Vaz-Velho, ManuelaThis study conducted a comprehensive comparison of two green extraction methods, microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE), for recovering bioactive phenolic compounds from Pinus pinaster bark. The goal was to valorize timber industry waste and enhance the value of by-products through the development of eco-friendly processes to extract phenolic compounds from Pinus pinaster Aiton subsp. atlantica in northwest Portugal. MAE achieved significantly higher extraction yields than UAE (11.13 vs. 3.47 g extract/100 g bark) and superior total phenolic content (833 vs. 514 mg GAE/g). MAE extracts also exhibited enhanced antioxidant activity in most assays tested (DPPH, ABTS, ORAC, and OxHLIA), while both extracts effectively inhibited lipid peroxidation (TBARS) and showed activity against Gram-positive bacteria. Phenolic profile analysis revealed that MAE recovered a substantially higher amount of total phenolic compounds (230.0 mg/g) compared to UAE (86.95 mg/g), with procyanidins identified as the predominant compounds. The greater recovery of this complex procyanidin mixture by MAE is strongly associated with the enhanced bioactivities observed. Overall, this study confirms MAE as a highly efficient and sustainable technology for transforming pine bark waste into valuable antioxidant and antimicrobial extracts with potential applications in the food and pharmaceutical industries.
- Bioactive metabolites from algae: occurrence, extraction techniques, functional properties, food applications and therapeutic prospectsPublication . Pereira, Cláudia S.G.P.; Carpena, M.; Barreira, João C.M.; Silva, Cristiana F.C.; Prieto Lage, Miguel A.; Oliveira, BeatrizThis review critically summarizes the major algal-derived bioactive compounds, including phenolics compounds (e.g., phlorotannins, bromophenols, phenolic acids), sterols (e.g., fucosterol, beta-sitosterol), and polysaccharides (e. g., carrageenan, fucoidan, ulvan), as well as key pigments such as astaxanthin, beta-carotene, lutein, violaxanthin, zeaxanthin, and chlorophylls. In addition, state-of-the-art extraction technologies including supercritical fluid extraction, pressurized liquid extraction, ultrasound assisted, microwave assisted, surfactant assisted, and enzyme assisted extractions, and carbon dioxide-expanded liquids) were systematically compared considering key parameters such as yield, versatility, compound selectivity, extract quality, cost-effectiveness, technical complexity, operational conditions, and sustainability principles. Based on this comparative evaluation, ultrasound assisted extraction emerged as the most versatile among advanced technologies, same as enzyme assisted extraction within ulterior techniques. The potential incorporation of these bioactive compounds into novel algaebased food systems, either as functional ingredients or texturizing agents, was also discussed. Moreover, their relevance in alternative therapeutic applications was also highlighted, with a proof-of-concept focused on the antiviral potential of sulfated polysaccharides (carrageenan, fucoidan, and ulvan). Overall, algae-based ingredients were found to be promising biofunctional agents for innovative food products, nutraceutical formulations, and therapeutic alternatives.
- CFD analysis of multi-layer cooling channels in three-dimensionally structured grinding wheelsPublication . Costa, Sharlane; Capela, Paulina; Hassui, Amauri; Ribeiro, J.E.; Pereira, Mário; Soares, DelfimMinimizing heat damage and surface integrity loss in grinding depends on effective cooling. Conventional techniques, however, suffer with low efficiency because of the fast air barrier restricting fluid access. Grinding wheels with internal cooling channels have been suggested to solve this; nonetheless, the impact of channel geometry and multi-layer topologies is yet unknown. This work investigates their effects on coolant flow pattern and thermal performance by means of computational fluid dynamics (CFD) simulations, experimental validation, and statistical optimization combined. The ideal arrangement was found by the Taguchi- Grey study to be 30 channels, 78 degrees inclination, 1.7 mm diameter and 2 mm interlayer distance. ANOVA determined that diameter (59.7 %) and number of channels (21.8 %) are the most influential parameters. CFD results showed that multilayer structures significantly increase fluid dispersion in the workpiece. The three-layer design stood out for providing the most uniform and dynamic fluid distribution, reducing cooling inconsistencies. Grinding tests confirmed that this configuration achieved the lowest temperatures for all different depths of cut. These findings highlight that increasing the number of flutes alone is insufficient; a three-dimensional flute structure with optimized geometry is essential to ensure efficient cooling. By integrating numerical modeling, statistical optimization, and experimental validation, this study provides a framework for designing grinding wheels with internal cooling channels, improving fluid distribution and thermal control.
- CFD and experimental investigation of channel diameter effects in structured internally cooled grinding wheelsPublication . Costa, Sharlane; Capela, Paulina; Sousa, Maria; Hassui, Amauri; Ribeiro, J.E.; Pereira, Mário; Soares, DelfimEfficient cooling and lubrication are critical in grinding due to the high specific energy and limited contact area involved. Conventional external methods often fail to penetrate the air barrier formed by the rotating wheel, leading to excessive heat generation and reduced process stability. To overcome this limitation, this study investigates vitrified alumina grinding wheels with internal cooling channels designed for directed fluid delivery. Three structured configurations were developed, all with identical total outlet area (similar to 54 mm(2)) but different channel diameters (0.6, 1.0, and 1.5 mm), to isolate the effect of channel size on fluid flow and grinding behavior. Computational fluid dynamics (CFD) simulations were performed to assess outlet velocity and surface coverage, while grinding tests quantified tangential and normal forces, temperature variation (Delta T), force ratio (F-t/F-n), and specific grinding energy. Narrow channels provided uniform surface coverage but limited jet velocity due to higher hydraulic resistance, whereas wider channels enhanced outlet velocity at the expense of flow uniformity. The intermediate configuration (& Oslash; 1.0 mm) yielded the most balanced performance, achieving up to 38 % lower tangential force and 41 % lower temperature than the & Oslash; 0.6 mm design, while maintaining low specific energy across all depths of cut. Correlation between CFD and experimental results confirmed that both jet intensity and spatial distribution govern cooling and lubrication efficiency. These insights support the design of more efficient and sustainable grinding wheels through tailored channel geometries.
- Chemical Routes for the Transformation of Bio‐monomers into PolymersPublication . Gomes, Catarina P.; Bzainia, Amir; Almeida, Ayssata Patrícia da Costa Leocádia Vaz; Martins, Cláudia D.; Dias, Rolando; Costa, Mário RuiThis chapter is devoted to the analysis of the main polymerization techniques used to transform monomers derived from plant biomass into polymers. Some of these polymers,or close related macromolecules,are naturally synthesized(e.g.by bacteria) and also produced via biotechnological processes (e.g. the polyhydrox-yalkanoate P(3HP)). The goal of the analysis here presented is the description of chemical synthesis routes eventually leading to a more widespread use of these biobased and renewable polymers. Lower production prices, opportunities for functional/structural tailoring, and production scalability are potential benefits of this approach compared to the biotechnological route (when available). Given their huge volumes, environmental and economic importance as well as Worldwide expression, the exploitation of olive-tree/-oilby-products and winemak-Ing waste streams to generate biopolymers comprises two sections of this work.
- Chestnut burrs as a sustainable source of cellulose for Pickering emulsion stabilisersPublication . Lains, Joana; Almeida, Heloísa H.S.; Barreiro, Filomena; Silva, Cláudia Gomes; Dias, Madalena M.; Santos, Ricardo J.; Ribeiro, Andreia; Martins, Isabel M.As the global population grows, increasing food consumption drives a significant rise in agri-food waste. In the northern Tras-os-Montes region of Portugal, one of the world's largest chestnut producers, this waste includes valuable by-products such as chestnut burrs, which are composed of 63% cellulose. This study aims to valorise chestnut burrs by extracting compounds for incorporation into high-added-value products. Cellulose was extracted through physical and chemical pre-treatments, alkali hydrolysis and bleaching. The process parameters were adjusted to enhance the extracted cellulose content and purity. Extracts were characterised by thermogravimetry and Fourier Transform Infrared Spectroscopy, and parameters such as particle size, zeta potential and wettability were also assessed and compared with commercial microcrystalline cellulose. Temperature was identified as the key parameter in alkali hydrolysis, with optimal conditions obtained for 10% NaOH at 100 degrees C for 1 h and a biomass-to-solvent ratio of 1:20 g/mL. Bleaching under optimal conditions (2% NaClO at 35 degrees C) removed an additional 7% lignin and enhanced the whiteness of the final product. The cellulose obtained has a purity of 72%, with a particle size of 55 mu m, a negative surface charge, hydrophilic behaviour, an estimated molecular weight of 13.2 kDa, and a crystallinity of 56.5%. When applied at 0.8 wt% of the aqueous phase in 20:80 oil-in-water emulsions, these particles stabilise Pickering emulsions with a 12 mm average droplet size, remaining stable for at least 30 days. These findings demonstrate that chestnut burrs are a viable and sustainable source of cellulose with high potential as a natural Pickering emulsion stabiliser for use in food, cosmetics, and pharmaceuticals.
- A Comprehensive Review of Fused Filament Fabrication: Numerical Modeling Approaches and Emerging TrendsPublication . Enriconi, Maria; Rodriguez, Rocío; Araújo, Márcia; Rocha, João; García-Martín, Roberto; Ribeiro, J.E.; Pisonero, Javier; Rodríguez-Martín, ManuelFused Filament Fabrication (FFF) has become a widely adopted additive manufacturing technology due to its cost-effectiveness, material versatility, and accessibility. However, optimizing process parameters, predicting material behavior, and ensuring structural reliability remain major challenges. This review analyzes state-of-the-art computational methods used in FFF, which are categorized into four main areas: melt flow dynamics, cooling and solidification, thermal-mechanical behavior, and material property characterization. Notably, the integration of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) has led to improved predictions of key phenomena, such as filament deformation, residual stresses, and temperature gradients. The growing use of fiber-reinforced filaments has further enhanced mechanical performance; however, this also introduces added complexity due to filler orientation effects and interlayer adhesion issues. A critical limitation across existing studies is the lack of standardized experimental validation methods, which hinders model comparability and reproducibility. This review highlights the need for unified testing protocols, more accurate multi-physics simulations, and the integration of AI-based process monitoring to bridge the gap between numerical predictions and real-world performance. Addressing these gaps will be essential to advancing FFF as a precise and scalable manufacturing platform.