RUN
Repositório Institucional da Universidade NOVA de Lisboa
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Detection of dietary stress and geophagic behaviour forced by dry seasons in Miocene Gomphotherium
Publication . Coimbra, Rute; Winter, Niels de; Ríos, Maria; Bernardino, Rui; Estraviz-López, Darío; Lohmann, Priscila; Martino, Roberta; Grandal-D'Anglade, Aurora; Rocha, Fernando; Claeys, Philippe; DCT - Departamento de Ciências da Terra; Copernicus Publications
To access the impact of anthropogenic emissions and land use change on Earth's climate and biodiversity, studies into the environment and ecology of natural ecosystems during past warm periods are required. The Miocene Climatic Optimum is a key reference period for future global warming scenarios. However, studies uncovering Miocene climate have heavily favoured marine environments, leaving the impact of warming on terrestrial ecosystems understudied. Here, we present a multi-disciplinary study into the chemical composition of fossil Gomphotherium angustidens (Proboscidea, Mammalia) teeth from the Middle Miocene Vb division (∼ 15.9–16.1 Ma) of western Portugal (Chelas Valley, Lisbon, Lusitanian basin) and their sedimentological context. Trace element and stable isotope compositions in these fossil teeth are compared with similar measurements in molars of a taxonomically related modern African elephant (captive Loxodonta africana). Results reveal seasonal-scale variability in trace elements in both fossil and modern proboscidean tooth enamel, which are interpreted as evidence for seasonal changes in diet. Periodic increases in Na, Fe and Si in G. angustidens demonstrate intake of sediment in the diet during fixed times of the year, a behaviour type previously described in modern elephants during dry seasons. In combination with the heavier carbon and oxygen isotopic composition in G. angustidens compared to L. africana, the terrestrial climate in Miocene Portugal appears characterized by seasonally dry periods, which forced geophagy behaviour of these large mammals and likely had significant consequences for the composition of Miocene ecosystems (e.g., food/water availability and potential seasonal range shifts) in southwestern Europe.
Valorisation of beetroot pulp and banana plant pseudostem by a combined mild enzymatic hydrolysis to fermentable sugars and bioconversion of hydrolysates to organic acids
Publication . Nascimento, Rosa E. A.; Carvalheira, Mónica; Brás, Teresa; Cabral-Marques, Helena; Papaioannou, Emmanouil H.; Crespo, João G.; Neves, Luísa A.; DQ - Departamento de Química; LAQV@REQUIMTE; UCIBIO - Applied Molecular Biosciences Unit; Instituto de Tecnologia Química e Biológica António Xavier (ITQB); Elsevier Science B.V., Amsterdam.
Beetroot pulp (BP) and banana plant pseudostem (PS) are abundant agricultural residues composed of lignocellulosic biomass (LB), which is rich in structural polysaccharides that can be converted to soluble sugars. However, they remain underutilized after beetroot juice production and banana fruit harvesting. Despite their widespread availability, a consistent and efficient strategy for the recovery of fermentable sugars and the subsequent fermentation of the resulting hydrolysates into value-added products is still absent. This study proposes a consolidated bioconversion route applicable to each of the BP and PS, by applying a tailored enzymatic cocktail (EC) for maximising the release of simple sugars and subsequently fermenting them to valuable organic acids. This EC, composed of cellulase, laccase, and pectinase was designed and employed for the first time to hydrolyse both LBs under comparable conditions. The enzymatic hydrolysis resulted in fermentable sugars’ recoveries of 860.53 ± 2.65 mg/g for BP and 744.82 ± 15.43 mg/g for PS, values that are equal or higher than those reported for other LBs treated enzymatically (425–776 mg/g) or by acid/base hydrolysis (114–486 mg/g). Subsequent fermentation of the simple sugars contained in the hydrolysates led to the production of acetic, butyric, and lactic acids, with concentrations of 4.04 ± 0.31 g/L and 3.91 ± 0.31 g/L for BP and PS, respectively. These results demonstrate the feasibility and applicability of the same enzymatic pre-treatment and fermentation strategy for two distinct agricultural residues, providing a practical methodology for LB valorisation and the sustainable production of organic acids relevant to industrial biotechnology and biorefinery applications.
Evaluation of Smartphone Camera Positioning on Artificial Intelligence Pose Estimation Accuracy for Exercise Detection
Publication . Oliosi, Eduarda; Ferreira, Soraia; Giordano, Ana Paula; Viveiros, Guilherme; Parraca, José; Pereira, Paulo; Guede-Fernández, Federico; Azevedo, Salomé; DF – Departamento de Física; LIBPhys-UNL; Comprehensive Health Research Centre (CHRC) - pólo NMS; JMIR Publications
Background: Artificial intelligence (AI)–driven pose estimation (PE) offers a scalable and cost-effective solution to track exercises in mobile health apps. However, occlusion, influenced by camera angle and distance, can reduce detection accuracy and repetition counting precision. The influence of smartphone positioning on these performance metrics remains underexplored in controlled studies. Objective: The study aimed to examine how smartphone camera angle (front, side, and diagonal) and distance (90 cm, 180 cm, 200 cm, and 360 cm) affect detection performance and repetition counting accuracy during push-ups and squats using AI-based PE. Methods: In this cross-sectional, within-subject study, 44 healthy university students (9 [20.5%] female participants; mean age 20.3 y, SD 0.4 y; mean BMI 23.2, SD 0.6 kg/m2) were assigned to perform either squats or push-ups. Each participant completed their assigned exercise across 12 predefined smartphone camera configurations, yielding approximately 264 squat trials (n=22) and 264 push-up trials (n=22). Each trial consisted of an average of 5 repetitions, totaling approximately 1320 repetitions per exercise. PE performance was assessed using binary classification accuracy, detection rate, and mean absolute error (MAE) for repetition counting. Generalized linear mixed-effects models evaluated classification odds, linear mixed-effects models analyzed MAE, and Tukey-adjusted post hoc tests followed significant effects. Results: The mean detection rate was 61.1% (SD 48.8%) for push-ups and 61.5% (SD 48.7%) for squats, with MAEs of 1.08 (SD 1.78) and 1.11 (SD 1.82) repetitions, respectively. Push-ups were most accurately detected from diagonal views at 90 to 180 cm (up to 85.7% detection; MAE=0.28) and least accurately from the front at 360 cm (20%; MAE=2.70). Squats performed best from a diagonal view at 200 cm (95.5%; MAE=0.05) and worst from the side at 90 cm (0%; MAE=5). Generalized linear mixed models showed that for push-ups, the front 90 cm and diagonal 360 cm views significantly reduced classification odds compared to the side 90 cm view (P=.03 and P=.04, respectively), whereas for squats, diagonal and front views significantly outperformed side views across all distances (P<.001). Post hoc tests confirmed that for push-ups, diagonal close or mid-range views had significantly lower MAEs than far front views, and for squats, diagonal and front views at 180 to 200 cm achieved the highest accuracy and lowest MAEs (P<.05). Conclusions: AI-based PE effectiveness for exercise tracking is significantly affected by smartphone positioning. Diagonal and frontal views at mid-range distances (180‐200 cm) provided the highest detection accuracy and counting precision. These findings offer actionable guidance for developers, clinicians, coaches, and users optimizing mobile health exercise monitoring.
Advanced Bacteriophage-Loaded Nanofiber Coatings for Active Food Packaging
Publication . Coelho, Fernanda; de Souza, Victor Gomes Lauriano; Silva, Pedro Miguel; Pastrana, Lorenzo; Sillankorva, Sanna; Zucolotto, Valtencir; DQ - Departamento de Química; MEtRICS - Centro de Engenharia Mecânica e Sustentabilidade de Recursos; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; Springer Science Business Media
The food industry faces significant challenges from microbial contamination, particularly by Salmonella, a leading cause of foodborne illnesses. Bacteriophages offer a promising biocontrol strategy due to their host specificity, safety, and environmental sustainability, but their practical application is limited by stability issues. This study presents a scalable approach to develop phage-functionalized antimicrobial packaging by electrospinning Felix O1 phage-loaded nanofibers composed of a dual hydrophilic polymer blend of sodium alginate and hydroxypropyl methylcellulose (HPMC) directly onto food-grade substrates (parchment paper and polystyrene). Parchment paper coatings achieved higher phage loading (≈109 PFU/mL) compared to polystyrene (≈108 PFU/mL), with thicknesses of 46.5 ± 0.24 µm and 59.7 ± 0.94 µm, respectively. Contact angles decreased from 107.6 to 45.7° on parchment and from 91.4 to 70.1° on polystyrene, indicating increased hydrophilicity, while water vapor transmission remained largely unchanged. Phage release exhibited a burst pattern, reaching ~ 100% release from parchment and films within 20 min, and 93.5% from polystyrene in 40 min. Antibacterial testing against Salmonella enteritidis demonstrated substrate-dependent efficacy. The electrospun films achieved the highest antimicrobial performance, with a 2.95 log reduction in bacterial counts, followed by coated parchment paper (2.05 log reduction), whereas polystyrene coatings exhibited a comparatively lower reduction of 0.76 log. These results were consistent with inhibition halo diameters of 24–25 mm for films, 16–17 mm for coated parchment, and slightly lower activity for polystyrene coatings. FTIR and mechanical analyses confirmed polymer deposition and improved tensile strength, particularly on parchment. These findings demonstrate that substrate surface properties strongly influence nanofiber deposition, phage incorporation, release kinetics, and antimicrobial efficacy. This work is the first to integrate bacteriophages into a dual-polymer electrospun nanofiber matrix directly applied to real-world food packaging, providing a practical and scalable strategy for active antimicrobial packaging.
From street level to science
Publication . Lau, Kevin; Lam, Cho Kwong Charlie; Krüger, Eduardo; Nouri, André Santos; Peng, Zhikai; Santucci, Daniele; Matzarakis, Andreas; MARE - Centro de Ciências do Mar e do Ambiente; DCEA - Departamento de Ciências e Engenharia do Ambiente; Springer Verlag
Urban heat risk is increasing, while fixed monitoring networks remain too sparse and coarse to resolve the pedestrian-scale variability, especially radiative loads, that governs outdoor thermal stress. This short communication advances the concept of climate walks, defined as route-based, human-centred field campaigns that build on earlier work on “thermal walks”, and presents them as a practice-ready methodology for design-relevant evidence. We define climate walks as structured, route-based, georeferenced assessments that pair high-resolution mobile microclimate measurements with synchronous in-situ human responses to capture transient, spatially heterogeneous conditions along actual walks. We synthesize key methodological features, such as dynamic, stop-and-go protocols; human-centred sensing; multisensory extensions; accessible kits from research-grade to low-cost platforms; and emerging diagnostics, and show how these produce actionable design measures. We discuss limitations and challenges, including lags and thermal memory, instrumentation and, index choice under transients, and the need for protocol harmonization. We then propose a research agenda to investigate dynamic conditions of outdoor thermal comfort, develop time-resolved, memory-aware comfort metrics, test indices under motion, mainstream multisensory models, and shift practice from isolated cool spots to connected, route-scale cool sequences. Together, these steps link biometeorology to actionable urban planning and design for heat-resilient, attractive public spaces.