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- Synthesis, characterisation, and thermal degradation kinetics of lignin-based polyurethane wood adhesivesPublication . Hernández-Ramos, Fabio; Esteves, Bruno; Carvalho, Luisa Hora de; Labidi, Jalel; Erdocia, XabierPolyurethane adhesives are widely employed in a range of industrial applications due to their exceptional bonding strength, flexibility, and chemical resistance. These materials play a crucial role in wood bonding technologies, where their versatility and durability make them ideal for creating strong, long-lasting joints. In this work, Four different polyurethane wood adhesives were synthesised using ligno-based bio-polyols obtained through microwave assisted liquefaction reaction of two wood species (hardwood and softwood) using polyethylene glycol and glycerol as solvents. The reaction conditions used for the synthesis of bio-polyols were optimised in a previous work. The synthesis of polyurethanes was carried out by one-shot method using Tetrahydrofuran (THF) as solvent and MDI as diisocyanate employing different NCO:OH ratios (2.0:1, 2.5:1, and 3.0:1). The chemical structure of polyurethanes was determined through ATR-FTIR and the shear strength was analysed using Automated Bonding Evaluation System (ABES) employing beech veneer strips. Through ABES it was concluded that an NCO:OH ratio of 2.5:1 was the formulation that showed the best shear strength for a pressing time of 120 s. Employing this ratio and the same synthesis procedure, two new polyurethanes were synthesised with the bio-polyols obtained using crude glycerol instead commercial glycerol. Finally, a study of thermal degradation kinetics employing the Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS) isoconversional methods of the polyurethanes synthesised with an NCO:OH ratio of 2.5:1 was carried out. On the one hand, the Ea of each system were estimated for the different α ratios, obtaining slightly higher values for the adhesives produced using commercial glycerol than crude glycerol. In addition, the pre-exponential factor was determined, enabling an estimation of the lifetime of the polymers. This study highlights demonstrated that crude glycerol could replace commercial glycerol without compromising adhesive properties. The findings revealed that the lignin source significantly influences the adhesive's characteristics and stability, while addressing challenges in achieving industrial viability remains essential for broader application.
- SLE-DAS enables an accurate definition of severe lupus disease activity: derivation and validation in a post hoc study of anifrolumab phase II and III studiesPublication . Diogo Jesus; Matos, Ana; Henriques, Carla; Andrea Doria; Luis Sousa InesObjectives This study aimed to derive and validate a cutoff for severe disease activity (SDA) using the SLE Disease Activity Score (SLE-DAS) and compare its accuracy and impact on health-related quality of life (HR-QoL) with the British Isles Lupus Assessment Group 2004 (BILAG-2004) and SLE Disease Activity Index 2000 (SLEDAI-2K). Methods We performed a post hoc analysis of pooled placebo arm data from the MUSE (A Phase II, Randomized Study to Evaluate the Efficacy and Safety of MEDI-546 in Subjects with Systemic Lupus Erythematosus), TULIP-1 and TULIP-2 (Treatment of Uncontrolled Lupus via the Interferon Pathway) trials, including 438 patients with moderate-to-severe SLE. SLE-DAS was scored retrospectively, and a cut-off for SDA was derived using receiver operating characteristic (ROC) curves against the BILAG-2004 numerical score >11 as gold standard. Multiple linear regression analysis and Cohen’s d effect size were applied to evaluate the effectiveness of SLEDAS, BILAG-2004 and SLEDAI-2K SDA classifications in capturing HR-QoL patient-reported outcomes (PROs). Results The optimal SLE-DAS cut-off for SDA was >9.90 (area under the ROC curve=0.847, sensitivity=77.8%, specificity=79.6%). Patients classified as SDA by both SLE-DAS and BILAG-2004 or only by SLE-DAS exhibited similar disease activity, while those classified by BILAG-2004 alone had less severe disease and better HR-QoL. The SLE-DAS cut-off was associated with worse HR-QoL across multiple PROs more consistently than BILAG-2004 or SLEDAI-2K. Conclusion The SLE-DAS cut-off for SDA provides an accurate definition of SDA in SLE, with good discriminative power and consistent associations with worse HR-QoL. This SLE-DAS definition enhances disease activity classification and offers a practical tool for guiding treatment decisions in clinical practice, as well as selecting patients with SDA for inclusion in clinical trials.
- Healthy motivations for food consumption in 16 countriesPublication . Guiné, Raquel; Joana Gonçalves; Florença, Sofia de Guiné e; Ferreira, Manuela; Cardoso, Ana Paula; Elena Bartkiene; Djekić, Ilija; Tarcea,Monica; Rumbak, Ivana; Sarić, Marijana Matek; Černelič-Bizjak, Maša; Isoldi, Kathy; EL-Kenawy, Ayman; Ferreira, Vanessa; Klava, Dace; Korzeniowska, Małgorzata; Vittadini, Elena; Leal, Marcela; Papageorgiou, Maria; Anjos, OféliaThere are many factors that can influence people’s attitudes towards healthy eating, including personal nature, sociodemographic influences, and lifestyle. This work investigated to what extent the motivations for healthy food consumption are shaped in individuals from different countries. A questionnaire survey was carried out on a sample of 11,919 participants from 16 countries. The results indicated that the strongest motivations for healthy food consumption were related to the perception of consuming healthy food, eating foods rich in vitamins and minerals, allied to food safety and hygiene concerns. Significant differences were found in healthy motivations between countries. Additionally, the sociodemographic variables that had a higher influence on health motivation levels were country, age, and gender. Concerning the anthropometric and lifestyle variables influencing healthy motivation for food consumption, the discriminating variables were: believing in having a healthy diet, physical exercise, and chronic diseases. In conclusion, the work showed important differences in the motivations for a healthy diet in different countries, but other variables also play a role in the motivation for the consumption of foods for health and well-being.
- Phenolic content, volatile composition and sensory profile of red wines macerated with toasted woods from different South American botanical speciesPublication . Jordão, António; Correia, Ana Cristina; Vasconcelos Botelho, Renato; Ortega-Heras, Miriam; González-SanJosé, MariaThe use of wood species from South American origin was not previously considered for wine aging. Thus, this work focuses on the comparative analysis of phenolic content, volatile composition and sensory characteristics of a red wine macerated with woods, in form of toasted cubes, from jequitibá, jaqueira, ipê, amburana and lenga species. All wines macerated with these woods showed a tendency for an increase of the phenolic parameters evaluated. This tendency was more evident in wine chromatic characteristics, especially for the wine macerated with jequitibá wood, where significantly higher color intensity and total color difference values was detected. For volatile composition, the different wood species induced significant changes on wine volatile profile. Thus, 3-hydroxy-4-phenyl-2-butanone was only detected in wine macerated with jaqueira wood, while benzophenone, ethyl pentadecanoate, D-citronellol, linalool, geranic acid and isovainillic acid were only detected in wine macerated with amburana wood. For sensory profile, wine macerated with amburana wood showed significantly higher scores for “coconut”, “toasted” and “floral” aroma descriptors, while for taste and overall appreciation this wine also showed a tendency for a slightly higher score. The outcomes of this research improved the knowledge of the use of several South American wood species on red wine characteristics.
- Optimized Production of Fungal Polygalacturonase Using Cupuaçu (Theobroma grandiflorum) Peel as Substrate and Its Effect on Clarification of Cupuaçu JuicePublication . Falcão, Lucas; Monteiro, Trisha; Azevedo, Sthéfanny; Batista, Bárbara; Jordão, António; Albuquerque, PatríciaPectinolytic enzymes play a key role in many beverages manufacturing processes, improving their clarification and filtration steps. Fungal pectinases are considered promising green catalysts for industrial applications, and they can be produced using fruit-processing residues as substrate. In this study, we investigated the optimal conditions to produce polygalacturonase from Aspergillus brasiliensis in a solid-phase bioprocess, using cupuaçu (Theobroma grandiflorum) peel as substrate. Then, the pectinolytic extract was applied in the clarification of cupuaçu juice. A central composite design was used to determine the optimal fungal cultivation conditions. Thus, the optimal fungal cultivation (maximum production of 11.81 U/g of polygalacturonase) was obtained using cupuaçu peel with 80% moisture, at 34 ◦C, for 7 days in a medium containing 4.2% phosphorus and 2.6% nitrogen. The enzymatic extract showed greater activity at 60 ◦C and stability at a pH range between 5.0 and 7.0. The pectinolytic extract was able to clarify the cupuaçu juice, causing a 53.95% reduction in its turbidity and maintaining its antioxidant activity. Our results demonstrate that the cupuaçu peel can be used as a substrate to produce polygalacturonase, and the enzymatic extract produced can be applied in the cupuaçu juice processing, contributing to the circular economy.
- Healthy motivations for food consumption in 16 countriesPublication . de Pinho Ferreira Guiné, Raquel; Gonçalves, Joana; Florença, Sofia G.; Ferreira, Manuela; Cardoso, Ana Paula; Bartkiene, Elena; Djekic, Ilija; Tarcea, Monica; Rumbak, Ivana; Sarić, Marijana Matek; Černelič-Bizjak, Maša; Isoldi, Kathy; EL-Kenawy, Ayman; Ferreira, Vanessa; Klava, Dace; Korzeniowska, Małgorzata; Vittadini, Elena; Leal, Marcela; Papageorgiou, Maria; Anjos, OféliaAbstract: There are many factors that can influence people’s attitudes towards healthy eating, including personal nature, sociodemographic influences, and lifestyle. This work investigated to what extent the motivations for healthy food consumption are shaped in individuals from different countries. A questionnaire survey was carried out on a sample of 11,919 participants from 16 countries. The results indicated that the strongest motivations for healthy food consumption were related to the perception of consuming healthy food, eating foods rich in vitamins and minerals, allied to food safety and hygiene concerns. Significant differences were found in healthy motivations between countries. Additionally, the sociodemographic variables that had a higher influence on health motivation levels were country, age, and gender. Concerning the anthropometric and lifestyle variables influencing healthy motivation for food consumption, the discriminating variables were: believing in having a healthy diet, physical exercise, and chronic diseases. In conclusion, the work showed important differences in the motivations for a healthy diet in different countries, but other variables also play a role in the motivation for the consumption of foods for health and well-being.
- Machine Learning Approaches for Predicting Maize Biomass Yield: Leveraging Feature Engineering and Comprehensive Data IntegrationPublication . Abbasi, Maryam; Vaz, Paulo; Silva, José; Martins, Pedro; Silva, José; ANTUNES VAZ, PAULO JOAQUIMThe efficient prediction of corn biomass yield is critical for optimizing crop production and addressing global challenges in sustainable agriculture and renewable energy. This study employs advanced machine learning techniques, including Gradient Boosting Machines (GBMs), Random Forests (RFs), Support Vector Machines (SVMs), and Artificial Neural Networks (ANNs), integrated with comprehensive environmental, soil, and crop management data from key agricultural regions in the United States. A novel framework combines feature engineering, such as the creation of a Soil Fertility Index (SFI) and Growing Degree Days (GDDs), and the incorporation of interaction terms to address complex non-linear relationships between input variables and biomass yield. We conduct extensive sensitivity analysis and employ SHAP (SHapley Additive exPlanations) values to enhance model interpretability, identifying SFI, GDDs, and cumulative rainfall as the most influential features driving yield outcomes. Our findings highlight significant synergies among these variables, emphasizing their critical role in rural environmental governance and precision agriculture. Furthermore, an ensemble approach combining GBMs, RFs, and ANNs outperformed individual models, achieving an RMSE of 0.80 t/ha and R2 of 0.89. These results underscore the potential of hybrid modeling for real-world applications in sustainable farming practices. Addressing the concerns of passive farmer participation, we propose targeted incentives, education, and institutional support mechanisms to enhance stakeholder collaboration in rural environmental governance. While the models assume rational decision-making, the inclusion of cultural and political factors warrants further investigation to improve the robustness of the framework. Additionally, a map of the study region and improved visualizations of feature importance enhance the clarity and relevance of our findings. This research contributes to the growing body of knowledge on predictive modeling in agriculture, combining theoretical rigor with practical insights to support policymakers and stakeholders in optimizing resource use and addressing environ mental challenges. By improving the interpretability and applicability of machine learning models, this study provides actionable strategies for enhancing crop yield predictions and advancing rural environmental governance.
- Crisis Communication in the digital age: bridging classic approaches with modern toolsPublication . Matias, Ana; Turk, Ezel; Lopes, AnaIntroduction: In the contemporary era, technological advancements and transformations in communication practices demand enhanced organizational communication strategies. Public entities must protect their reputations and engage stakeholders effectively, leveraging new media to address crises and mitigate negative impacts. Crises - inherent to human activity -, are projected to rise in the next years, necessitating robust crisis communication frameworks for risk identification, prevention, and response; this way, strategies should include stakeholder engagement, media interaction, and transparent messaging. This research explores best practices in crisis communication, proposing coding categorization to bridge theoretical and practical approaches for effective crisis management in a digital context. Objectives 1. To analyze best practices in crisis communication by exploring theoretical and practical frameworks, emphasizing effective messaging strategies and stakeholder engagement during different stages of a crisis. 2. To investigate the role of digital and social media platforms in modern crisis communication, assessing their opportunities for real-time engagement and challenges related to misinformation and swift information dissemination. 3. To propose a coding categorization framework for future empirical studies, aiming to enhance the adaptation of crisis management strategies in diverse organizational contexts and unfavorable digital environments. Methodology A qualitative methodology was employed, combining theoretical and methodological elements. The approach included a literature review to identify knowledge gaps, a documentary analysis of scientific materials to extract relevant criteria, and the development of a theoretical model for content categorization. The proposed framework was validated against existing theories, ensuring coherence and adaptation to the digital context. Results Effective crisis communication requires a combination of offline and online tools to ensure a coordinated response and maintain trust. A Crisis Management Plan provides a strategic framework, outlining roles, responsibilities, and operational strategies, while a Crisis Communication Plan focuses on real-time information flow and engagement with stakeholders, media, and the public. Forming a crisis team, assigning spokespersons, and utilizing tools such as messaging templates, press releases, email communication, and official websites are essential components of effective crisis communication. Digital platforms, especially social media, play a crucial role in crisis communication by enabling real-time, two-way interactions and addressing misinformation promptly. Platforms like X (formerly Twitter), Instagram, and YouTube allow organizations to disseminate updates, engage with stakeholders, and foster community resilience. Social media tools and analytics, such as Google Analytics, Facebook Insights, and Twitter Analytics, as well as social listening tools like Brandwatch, Hootsuite, and Mention help track the crisis's impact and refine strategies in real time, ensuring a transparent and reliable approach to crisis management. Strategies for apologies, transparency, image repair, or corrective action can be adapted to social media. Regarding response strategies discussed in the literature (Benoit, 2015; Coombs, 2007, 2017; Liu et. al., 2011; Jin, Pang, & Cameron, 2012), a systematic coding framework can be used to categorize social media crisis content by message type, tone, audience, and engagement, helping organizations optimize their strategies and evaluate effectiveness Conclusions Crisis communication is a cornerstone of organizational resilience, requiring strategic preparation, response, and post-crisis evaluation. Preparation involves proactive measures like risk assessments, communication planning, and team training to enhance readiness and mitigate risks; in crises, transparency, timeliness, and consistent messaging are vital to counter misinformation and maintain credibility. Social media platforms, such as X and YouTube, enable real-time engagement and broad reach but also present challenges like misinformation. Digital tools, including analytics and monitoring software, help refine messaging and target stakeholders more effectively. This research introduces a coding framework to analyze communication strategies by categorizing message types, tones, and audience engagement. Combining traditional and digital approaches fosters trust, supports recovery, and strengthens organizational resilience in today’s complex global environment.
- Parametric Analysis of Steel Studs to Reduce Thermal Bridges in Light Steel Framing Construction SystemsPublication . Langner, Marcelo; Soares, Thais A.; Figueiredo, Antonio; Almeida, Ricardo; Vicente, RomeuThermal bridges significantly affect the thermal performance of light steel framing systems due to the high thermal conductivity of steel. The objective of this study is to identify modifications on the steel profiles to reduce heat flux and improve the thermal resistance of both single- and double-layer wall panels. Three approaches were analyzed: (i) slotted steel studs, (ii) integration of less-conductive materials into the web section, and (iii) modifications to web geometry. A numerical model was calibrated based on experimental data and used to perform dynamic simulations with different configurations. Results show that incorporating less-conductive materials, such as rigid polyamide, achieved a heat flux reduction of up to 98%, while optimized slotted patterns reduced heat flux by up to 90%. The results also demonstrated that all web modifications effectively reduced heat flux through the wall, with approaches (i) and (ii) showing the greatest impact. The shape of the slots also has an important impact on the heat flux. The most effective strategy for enhancing the thermal performance of the steel studs was the use of a less-conductive material.
- Enhanced Properties of Cryptomeria japonica (Thunb ex L.f.) D.Don from the Azores Through Heat-TreatmentPublication . Esteves, Bruno; Nunes, Lina; A. Lopes, Rogério; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa PaulaThis study evaluates the chemical, physical, mechanical, and biological properties of untreated and heat-treated Cryptomeria japonica (Thunb ex L.f.) D.Don wood from the Azores, Portugal. Heat treatment was performed at 212 ◦C for 2 h following the Thermo-D class protocol. Chemical analysis revealed an increase in ethanol soluble extractives and lignin content after heat treatment, attributed to hemicellulose degradation and condensation reactions. Dimensional stability improved significantly, as indicated by reduced swelling coefficients and higher anti-swelling efficiency (ASE), particularly in the tangential direction. Heat-treated wood demonstrated reduced water absorption and swelling, enhancing its suitability for applications requiring dimensional stability. Mechanical tests showed a decrease in bending strength by 19.6% but an increase in the modulus of elasticity (MOE) by 49%, reflecting changes in the wood’s structural integrity. Surface analysis revealed significant color changes, with darkening, reddening, and yellowing, aligning with trends observed in other heat-treated woods. Biological durability tests indicated that both untreated and treated samples were susceptible to subterranean termite attack, although heat-treated wood exhibited a higher termite mortality rate, suggesting potential long-term advantages. This study highlights the impact of heat treatment on Cryptomeria japonica wood, emphasizing its potential for enhanced stability and durability in various applications.