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Adherence to the mediterranean diet and metabolic health in older adults: insights from a feasibility study
Full text linkThe Mediterranean Diet is known for its protective effects against cardiovascular
and metabolic diseases. Metabolic syndrome, characterized by multiple health
risk factors, is increasingly concerning in older populations. Understanding dietary impacts
on metabolic health is key for promoting healthy ageing. Objectives: This feasibility
study aimed to explore the relationship between adherence to the Mediterranean Diet
and metabolic risk factors in older adults participating in a community exercise program
and to evaluate the feasibility of applying validated tools in this setting. Methods: A
cross-sectional design was used. Adherence to the Mediterranean Diet was evaluated using
the PREDIMED questionnaire, while Metabolic Syndrome was evaluated according to
National Cholesterol Education Program criteria. Blood samples were taken following
WHO guidelines. Results: Ten participants (mean age 73.1 years; 90% women) were included.
50% showed high adherence to the Mediterranean Diet, while 40% had moderate
or low adherence. No participants met the full criteria for Metabolic Syndrome. Significant
associations were found between Mediterranean Diet adherence and chronic disease
(r = 0.869, p < 0.01), and an inverse correlation with the number of Metabolic Syndrome
criteria (r = –0.707, p < 0.05). The Mediterranean Diet score was also inversely related to
cholesterol (r = –0.740, p < 0.05). Conclusions: Higher adherence to the Mediterranean Diet
was associated with better metabolic profiles, highlighting its potential protective role. The
study demonstrates the feasibility of incorporating nutritional screening in community
exercise programs for older adults. Future research should include larger and longitudinal
samples and integrate inflammatory biomarkers
Synergies for cross-border tourism: a collaborative proposal for rural revitalization in Northern Portugal and Spain
No full textAttracting tourists to rural areas is a complex challenge, often overshadowed by the allure of urban or beach destinations. Limited infrastructure, sparse amenities, and a lack of visibility in the tourism industry contribute to the difficulty in drawing visitors to these less-explored regions. Accessibility issues, stemming from limited transportation options, further deter potential tourists, as rural destinations may be challenging to reach compared to well-connected urban centres. To address these challenges, collaborative efforts are essential. Regional entities must work together to make rural areas more appealing to tourists seeking unique adventures off the beaten path. The visibility of rural destinations also requires collaborative promotional campaigns that leverage digital platforms and social media to reshape perceptions about rural travel. This study introduces a project aiming to develop an online platform supporting the structuring of tourist products in the cross-border areas of Northern Portugal and Castile and León in Spain. Focusing on nature tourism, wine and gastronomy, cultural and landscape tours, and active tourism, the project addresses common challenges such as aging populations, depopulation, and limited digital connectivity in both regions. By fostering collaboration and offering a structured approach to sustainable and ecological tourism, the project aims to enhance visitor attraction and promote synergies between the resources of both regions. The proposed online platform will provide comprehensive tourist information about the cross-border areas, facilitating the commercialization of tourist resources in a structured manner. Whether suggesting frequenting independent travellers or collaborating with tour operators and inbound travel agencies, the goal is to stimulate tourist attraction, prolong their stay in the region, and boost the economy of these cross-border areas.info:eu-repo/semantics/publishedVersio
Predictors of the Intention to Buy Organic Products: A Quantitative and Cross-sectional Study in Tunisia
No full textOrganic farming plays a very important role in promoting sustainable agriculture by preserving ecosystems, enhancing biodiversity, and ensuring the production of healthier food. As the demand for organic products continues to rise globally, understanding the factors driving organic food consumption becomes essential for fostering sustainable consumer behavior. Tunisia, with its deep-rooted agricultural heritage and growing interest in organic and sustainable living, presents a unique case for examining these dynamics. Given the country’s ongoing economic development and urbanization, it is crucial to examine the factors influencing consumer choices regarding organic products. Thus, this study aims to analyze the factors influencing organic food consumption in Tunisia by assessing consumer attitudes, purchasing habits, and barriers to its implementation. Using a quantitative and cross-sectional approach, data were collected through a structured survey targeting a diverse sample of Tunisians that explored socio-demographic characteristics, economic constraints, motivations, and challenges of consuming organic food. Statistical analysis was applied to identify key trends and correlations. Findings reveal that 23% of respondents purchase no organic products, with supermarkets dominating distribution channels and limited availability through direct farmer sales or specialty stores. Consumer knowledge is notably deficient, with over 60% of participants demonstrating limited understanding of organic food. Regression analysis reveals that attitudes toward organic food are the strongest predictor of purchase intention, followed by health awareness, while perceived price has a negative impact on consumption. Interestingly, environmental concerns showed no significant association with purchase intention. These results underscore the need for strategies that foster positive attitudes and address price concerns to promote the implementation of organic food in Tunisia.This work was supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020)
Understanding Dropout in Postgraduate Education: Challenges and Institutional Responses
No full textDespite growing enrolment in postgraduate education, completion rates remain low, often falling below those of undergraduate programmes. This disparity has raised concerns about the adequacy of current retention strategies, which are frequently designed with undergraduate students in mind and may overlook the specific needs of postgraduate learners. Master’s students often face distinct challenges, including balancing professional responsibilities, aca-demic demands, and family obligations, all of which contribute to a heightened risk of dropout. This study investigates the institutional factors contributing to non-completion in master’s education through a qualitative case study at a pub-lic higher education institution in Portugal. Using an adapted Delphi methodol-ogy, data were collected through semi-structured interviews with first-year stu-dents and follow-up interviews with postgraduates to validate and deepen the findings. The results reveal three key areas influencing student retention: the early alignment between coursework and dissertation topics, the consistency and support provided by thesis supervisors, and the degree of flexibility in insti-tutional scheduling and workload management. Based on these insights, the study proposes practical recommendations such as structured dissertation time-lines and increased opportunities for academic engagement, including participa-tion in conferences. These measures can help higher education institutions re-duce attrition and improve the postgraduate experience by aligning academic structures with students' lived realities
Proteomic analysis may explain differences in Citrus × limon and Citrus × sinensis susceptibility to Trioza erytreae
No full textThe psyllid Trioza erytreae is a vector for Huanglongbing, one of the most destructive citrus diseases worldwide. Citrus × limon is the preferred host, although the mechanisms underlying this preference remain poorly understood. This study compared the responses of C. × limon ’Eureka’ and C. × sinensis ‘Valencia’ plants to T. erytreae infestation, specifically to nymph feeding. The number of successfully developed nymphs observed in C. × limon was three times that of ‘Valencia’ plants. The enriched vascular sap proteome of young leaves from infested and control plants was compared using nanoscale liquid chromatography coupled to tandem mass spectrometry. This study identified 48 and 1265 differentially abundant proteins (DAPs) in infested C. × limon and C. × sinensis, respectively. There was a marked host-specific response, with little overlap in proteomic features. Common citrus host responses to infestation were the downregulation of ‘Amino sugar and nucleotide sugar metabolism’ and the upregulation of galactose, vitamin B6, and selenocompound metabolisms. The downregulation of photosynthesis-related proteins and the activation of defence-related pathways in C. × sinensis suggest a robust response, which may explain the low success rate of nymph development on this host. The lower number of DAPs in C. × limon infested with T. erytreae, in comparison to the respective control, may be indicative of a reduced stress response. Further investigation into the identified candidate proteins and pathways is expected to contribute to the elucidation of the interaction between T. erytreae and C. × limon.This study was financially supported by the ‘European Union Horizon 2020’, through the research project Grant agreement ID: 817526 (Pre-HLB ‘Preventing HLB epidemics for ensuring citrus survival in Europe.’). Tomás Magalhães would like to acknowledge the financial support provided by the ‘Fundação para a Ciência e Tecnologia’ (FCT—Portugal), through the research project 2020.07798.BD (‘Understanding host preference of Trioza erytreae (Del Guercio) by a multi-omics approach’) (https://doi.org/10.54499/2020.07798.BD). Liliana Anjos was funded by FCT, under the ‘Norma Transitória’-DL57/2016/CP1361/project CT0011. Further financial support was received from the Centers of Investigation, which were funded by FCT/MCTES: R&D unit MED - Mediterranean Institute for Agriculture, Environment and Development (https://doi.org/10.54499/UID/05183/2025) and the Associate Laboratory CHANGE – Global Change and Sustainability Institute (https://doi.org/10.54499/LA/P/0121/2020); CIMO (https://doi.org/10.54499/UIDB/00690/2025 and https://doi.org/10.54499/UIDP/00690/2025) and SusTEC, LA/P/0007/2020 (doi: 10.54499/LA/P/0007/2020)
Aplicação de proteína de Spirulina platensis como emulsionante na elaboração de gelados
No full textMestrado de dupla diplomação com a UTFPR, Universidade Tecnológica Federal do ParanáO presente trabalho teve como objetivo principal desenvolver gelados utilizando emulsionantes
à base de Spirulina platensis e avaliar suas propriedades físicas e sensoriais. Foram utilizados
dois tipos de emulsionantes: biomassa de Spirulina platensis em pó e extrato proteico de
Spirulina, tendo sido utilizado um emulsionante comercial como controle. Os gelados foram
preparados com diferentes formulações (25, 50, 75 e 100% dos novos emulsionantes), levando
em consideração o teor de proteína presente na biomassa e no concentrado proteico de
Spirulina. As curvas de congelação dos gelados foram determinadas registando-se a
temperatura de congelação ao longo do tempo. As propriedades físicas dos gelados foram
avaliadas através da análise da derretibilidade, do overrun (incorporação de ar) e da textura. A
análise sensorial foi realizada com a participação de 50 provadores, os quais avaliaram a
aparência geral, cor, textura, sabor e apreciação geral de três gelados (controlo (gelado
preparado com o emulsionante comercial), 100% biomassa e 100% concentrado proteico como
emulsionantes) numa escala hedónica não estruturada. Os resultados demonstraram que as
curvas de congelação dos vários gelados foram semelhantes. Pelo contrário, a adição de
Spirulina (biomassa e concentrado proteico) afetou a cor dos gelados, mas não influenciou
significativamente a derretibilidade e o overrun. Em termos de textura, avaliada por dois tipos
de ensaio, medição da força de compressão, determinada durante o teste com a célula de corte
Knife Edge (HDP/BS) (Lâmina Warner Bratzler), e da espalhabilidade (spreadability),
verificou-se que os gelados com biomassa de Spirulina mostraram-se mais suaves e menos
resistentes ao corte em comparação com o gelado controlo. Pelo contrário, os gelados com
concentrado proteico mostraram um comportamento mais variável em relação à textura. Em
relação à análise sensorial, o gelado controlo foi o melhor classificado em termos de aparência
geral, sabor e apreciação geral. Pelo contrário, os provadores classificaram de forma idêntica
os três gelados em relação à textura. O gelado controlo foi o preferido por cerca de 43,8% dos
provadores, seguido do gelado com o concentrado de Spirulina (31,3%). Em conclusão, os
resultados obtidos fornecem informações importantes para o desenvolvimento futuro de
gelados mais saudáveis e sustentáveis, atendendo às preferências dos consumidores.The present work had as main objective to develop ice creams using emulsifiers based on
Spirulina platensis and to evaluate their physical and sensory properties. Two emulsifiers were
used: powdered Spirulina platensis biomass and Spirulina protein extract, using a commercial
emulsifier as a control. The ice creams were prepared with different formulations (25, 50, 75
and 100% of the new emulsifiers), considering the protein content present in the biomass and
in the Spirulina protein concentrate. The ice cream freezing curves were determined by
recording the freezing temperature over time. The physical properties of the ice creams were
evaluated through the analysis of meltability, overrun (incorporation of air) and texture.
Sensory analysis was carried out with the participation of 50 tasters, who assessed the overall
appearance, colour, texture, flavour and general appreciation of three ice creams (control (ice
cream prepared with the commercial emulsifier), 100% biomass and 100% protein concentrate
as emulsifiers) on an unstructured hedonic scale. The freezing curves of the various ice creams
were similar. On the contrary, adding Spirulina (biomass and concentrated protein) affected the
colour of the ice creams but did not significantly influence the meltability and overrun. In terms
of texture, evaluated by two types of tests, measurement of the compressive strength,
determined during the test with the Knife Edge (HDP/BS) cutting cell (Warner Bratzler blade),
and the spreadability, it was found that the ice creams with Spirulina biomass were softer and
less resistant to cutting compared to the control ice cream. On the contrary, ice creams with
protein concentrate showed a more variable behaviour concerning texture. Concerning sensory
analysis, the control ice cream was ranked the highest in overall appearance, flavour and general
appreciation. On the contrary, the tasters identically classified the three ice creams in relation
to texture. The control ice cream was preferred by about 43.8% of the tasters, followed by the
ice cream with Spirulina concentrate (31.3%). In conclusion, the present results provide
important information for the future development of healthier and more sustainable ice creams
to meet consumer preferences
Fire performance of light timber frame construction in Europe: a review on fire protection measures and fire safety design
Full text linkTimber construction is becoming increasingly relevant for the climate and energy transition of the building sector. Notably, modern multilayered light frame elements are attractive due to their versatility and ease of prefabrication, and they are now used in a wide range of building heights and occupancies. However, wood and wood-based products are combustible, and verifying the fire resistance of timber frame elements and certification of innovative eco-materials require appropriate design and fire testing. This work contextualises the relevance of European timber structures towards the green transition. It further discusses the fire performance and fire safety design of light timber frame systems, emphasising passive fire protection measures. The paper also briefly addresses new developments in Eurocode 5 related to fire resistance verification of light timber frame elements. Additionally, as increasingly complex and innovative assemblies arise in construction practice, developing advanced models, such as finite element and comprehensive multiscale models, is required for performance-based fire engineering and product development. These models simulate the thermal and structural behaviour of timber at elevated temperatures, providing practical tools for assessing fire resistance. Therefore, an instructive background on comprehensive models for modelling the fire behaviour of timber is presented. This work is intended to be a one-stop reference for understanding the relevance of timber elements in Europe and the fire protection and fire safety design strategies for light timber frame construction within the framework of European guidelines.Matheus Alves acknowledges the National funding by FCT, Foundation for Science and Technology, through the individual research grant (2022. BD.13536).info:eu-repo/semantics/publishedVersio
Machine learning prediction of adolescent obesity using physical fitness data
No full textThe escalating prevalence of obesity among adolescents has emerged as a critical global public health challenge. Machine learning techniques have been used to predict obesity in adolescents. This study aimed to develop and validate a robust obesity prediction model for adolescents using this hybrid approach, leveraging data from a diverse cross-sectional population-based study. The hybrid method combines statistical inference with non-linear machine learning to enhance prediction accuracy. Physical fitness data were collected from the FITescola® tests. Multiple tests were employed to evaluate physical fitness. Multiple Poisson's multiple regression method was applied to identify the most predictive variables set of the adolescent's body mass index (BMI) classification. The model's goodness-of-fit statistics indicate a strong fit, with a log-likelihood of 8068.6 and a Pseudo R-squared value of 0.8853, where the aerobic fitness (AF), upper limb strength (ULS) and lower limb flexibility (LLF) presented an inverse association with the adolescent's BMI. In contrast the adolescent's core strength presented a positive association with their body mass. The random forest regression showed that an average of 35 repetition on the yo-yo test predicted a healthy BMI percentile [predBMIperc = 0.31]. In addition, the model presented good validity [MAE = 0.36, MSE = 0.20, RMSE = 0.45, R2 = 0.54]. The model's strong fit and accurate random forest regression's predictions suggest that physical fitness components, such as aerobic fitness, upper limb strength, lower limb power, and core strength, play a significant role in obesity risk among adolescents
The impact of artificial intelligence on digital marketing
No full textThis chapter explores the revolutionary impact of Artificial Intelligence (AI) on digital marketing, considering its potential and the ethical implications involved. AI has transformed marketing strategies through hyper-personalization, automation, and datadriven decision-making, allowing businesses to deliver customized consumer experiences on a large scale. Some of AI’s most significant applications include AIpowered chatbots, predictive analytics, programmatic advertising, and generative content creation tools, all of which enhance efficiency, engagement, and overall operational performance. However, these advancements also raise serious concerns about data privacy, algorithmic bias, transparency, and the potential decline of humancentric marketing approaches. The discussion emphasizes the need for ethical frameworks, regulatory compliance, and balanced human-AI collaboration to ensure responsible implementation. Additionally, the chapter highlights emerging trends, such as AI’s role in sustainable marketing and voice search optimization, while proposing future research directions to address gaps in consumer trust, global implementation disparities, and the authenticity of AI-generated content. By synthesizing current knowledge and practical insights, this chapter provides a comprehensive perspective on AI’s evolving role in digital marketing, underscoring the importance of aligning technological innovation with consumer rights and ethical standards
Optimization and Validation of the SBSE–HPLC–FLD Method for the Determination of Priority Pollutants PAHs in Several Water Matrices
No full textPolycyclic aromatic hydrocarbons (PAHs) are priority pollutants in drinking and environmental waters. Their mutagenic/carcinogenic potential and ng.L-1 limits demand methods that are both sensitive and practical. We report a rapid, solvent-sparing workflow coupling stir-bar sorptive extraction (SBSE) to HPLC with fluorescence detection (FLD) for simultaneous determination of six PAHs (fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, indeno[1,2,3-cd]pyrene) in drinking water, groundwater, and surface water. SBSE conditions were optimized, and isocratic RP-HPLC achieved baseline resolution within a 26-min cycle using similar to 39 mL solvent (similar to 20 samples day - 1). Validation under ISO/IEC 17,025 showed linear calibration (r >= 0.99941), limits of detection of 0.4-1.8 ng.L-1, and matrix-verified LOQs of 1.5-10.9 ng.L-1. Trueness and precision met predefined criteria across matrices (recoveries 63.3-109.9%; within-laboratory reproducibility <= 25% RSD), with expanded uncertainties U(k = 2) <= 47.1%. Performance satisfies EU Drinking Water Directive 2020/2184 requirements for benzo[a]pyrene and the regulated PAH sum. By attaining sub-10 ng.L-1 LOQs with FLD alone and documenting a complete uncertainty budget, this procedure offers a cost-effective alternative to LC-MS/MS for routine compliance and surveillance. The validated SBSE-HPLC-FLD protocol is fit-for-purpose for regulatory laboratories and environmental services requiring sensitive, robust, and scalable PAH determination across diverse water matrices.This work is supported by National Funds by FCT –Portuguese Foundation for Science and Technology, under the projects UID/04033: Centro de Investigação e de Tecnologias Agro-Ambientais e Biológicas and LA/P/0126/2020 (https://doi.org/10.54499/LA/P/0126/2020 Juliana Garcia and Eduardo Lage acknowledge funding support from Portuguese public funding through Investimento RE-C05-i02 – Missão Interface N.° 01/C05-i02/2022