Sapientia
Repositório Científico da UAlg
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Behavioral flexibility and its drivers in semi-urban vervet monkeys
Publication . Barnes, Paige; Robira, Benjamin; Mercier, Stéphanie; Forss, Sofia
Phylogenetic comparisons suggest that behavioral flexibility facilitates success in urban environments. It remains less clear whether urbanization fosters cognitive skills that require flexibility, or whether successful individuals in urban environments simply apply pre-evolved skills to solve new problems. To investigate whether variation in anthropogenic experience drives behavioral flexibility required to solve a new technical problem, we presented 42 semi-urban vervet monkeys (Chlorocebus pygerythrus) with a 3-phase foraging experiment. Each monkey's tendency to forage on human structures for food was measured to assess their exposure to human environments. We then used a sequential decision-tree-based probabilistic model to describe the series of monkeys’ actions when attempting the task, quantifying 3 behavioral flexibility traits: switch tendency (shifting between known solutions between trials), innovativeness (ability to use unknown solutions), and learning sensitivity (ability to repeat known solutions). We found that individuals' switch tendency and innovativeness were not explained by anthropogenic experience and that the 3 traits were mostly unrelated to each other. Moreover, neither switch tendency, nor innovativeness predicted monkeys’ human food consumption in this habitat. Thus, our study suggests that behavioral flexibility is not driven by anthropogenic foraging experience. Contrasting with the hypothesis that urbanization selects for behavioral flexibility, our findings instead imply that vervet monkeys already had sufficient behavioral flexibility and cognitive capacities to successfully exploit the urban habitat.
Tourist behaviour in four- and five-star hotels in the Algarve before and during the covid-19 pandemic: an analysis of online reviews
Publication . Ferreira, Ana; Correia, Marisol B.; Renda, Ana Isabel; Antonio, Nuno
This study aims to examine the behaviour of tourists staying in four- and five-star hotels in Portugal’s Algarve region before and during the pandemic and to identify differences between these periods. To achieve this, 17,601 online reviews published on Trip Advisor between January 2018 and April 2023 were analysed using NVivo 14 software. The findings reveal that guest behaviour during the pandemic closely mirrored pre-pandemic patterns, except for variations related to tourists’ continent of origin.
Adsorption of cationic lignin derivatives on negatively charged model surfaces and hair fibers: implications for hair conditioning performance
Publication . Catarina Fernandes; Cabaça, Daniela; Guzmán, Eduardo; Serra, Ricardo; Eivazi, Alireza; Norgren, Magnus; Alves, Luís; Medronho, Bruno; Rasteiro, Maria da Graça; Varela, Carla
The application of cosmetic ingredients into hair formulations relies on their extensive characterization and on understanding their mechanisms of action. Specifically, in the case of hair conditioning agents, their efficiency in treating hair must be proved before testing them on real complex formulations. In this work, we investigate the deposition of three cationic polymers onto model surfaces that mimic the negative surface potential of highly damaged hair. Two CHPTAC-cationized lignins (CL0.34 and CL0.61) were evaluated and compared with a commercial polyquaternium (PQ11). The two selected lignin derivatives exhibited different degrees of cationic substitution (DS) and ζ-potential (CL0.34: DS = 0.34 ± 0.01 and ζ-potential = 12.8 ± 0.4 mV; CL0.61: DS = 0.61 ± 0.03 and ζ-potential = 18.8 ± 0.3 mV). Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D) were used to evaluate the adsorbed layers formed by the polymers and their mechanical properties. Among the tested lignin conditioning agents, CL0.61 exhibited conditioning behavior, forming layers whose properties closely resembled those of the benchmark polymer PQ11. CL0.61 and PQ11 were both efficient at reducing the frizz effect on real bleached hair, effectively overcompensating the hair surface potential, which shifted from negative to positive values, confirming their effective adsorption after conditioning and rinsing. By combining advanced interfacial characterization with structure–property–function relationships, this work provides fundamental insights into polymer adsorption and performance at biointerfaces, supporting the rational design of functional materials and highlighting the potential of cationic lignin derivatives as viable, biobased conditioning agents for future hair-care formulations.
Contaminant metal concentrations in holothurians: seasonal, sex and tissue variations
Publication . Sales, Sabrina S.; Gonzalez-Wanguemert, Mercedes; Bandarra, Narcisa M.; Breves, André; Lourenço, Helena M.
The main goal of this study was to investigate seasonal contaminant changes in three sea cucumber species caught in the North Atlantic. The risk associated with the consumption of these target species, taking into account the consumers age group, was also evaluated. For this purpose, the concentration of toxic metals cadmium (Cd), lead (Pb) and mercury (Hg) was analyzed during spring, summer, autumn and winter in two different tissues of female and male holothurians. Average concentration of the Cd, Pb and Hg were different among the studied species, and significant differences were observed considering sex, tissue and seasonality factors. The average values (dry weight) of the Cd and Hg of Holothuria arguinensis (Cd: 0.10 mg kg− 1 ; Hg: 0.10 mg kg− 1 ), Holothuria forskali (Cd: 0.10 mg kg− 1 ; Hg: 0.07 mg kg− 1 ) and Holothuria mammata (Cd: 0.19 mg kg− 1 ; Hg: 0.17 mg kg− 1 ) were lower than those regulated by the European Union. On the other hand, the average Pb values (dry weight) were high in Holothuria arguinensis (Pb: 2.97 mg kg-1) and Holothuria mammata (Pb: 1.77 mg kg-1). The risk associated with the consumption rate (CRlim) of these species is low for Cd and Hg and high for Pb for adults and children, based on the maximum concentrations rate (CRlim) of each metal. Results such as presented in this work are scarce or non-existent, potentially contributing to a database that allows for the future development of new regulations that limit the maximum concentrations of metals in the consumption of echinoderms.
Access to public green spaces as a factor in combating environmental injustice
Publication . de Sousa Silva, Catarina; Bell, Simon; Lackóová, Lenka; Panagopoulos, Thomas
Ensuring equitable access to urban green spaces is a major challenge in contemporary urban planning, with important implications for public health, well-being and environmental justice. However, comparative cross-city analyses based on harmonised methodologies remain limited, particularly across contrasting European climatic and morphological contexts. This study aims to: (i) assess the spatial distribution of public green spaces; (ii) evaluate neighbourhood-level accessibility and identify environmental justice inequalities; and (iii) examine how urban form and climatic context influence accessibility outcomes across the following three medium-sized European cities: Faro (Portugal), Tartu (Estonia) and Nitra (Slovakia). A GIS-based approach was applied using consistent criteria, including publicly accessible green spaces ≥ 1 ha, Euclidean buffers of 300 m and 500 m, and harmonised population data from the Global Human Settlement Layer (GHSL). Accessibility was quantified as the proportion of residents living within the defined walking-distance thresholds. The results reveal substantial inter- and intra-urban disparities. Tartu exhibits the highest green space provision (23.34 m2/inhabitant), while Faro presents the lowest (5.67 m2/inhabitant). However, accessibility patterns do not directly reflect provision levels: Faro achieves accessibility values at 500 m comparable to those of Tartu, whereas Nitra shows lower accessibility despite moderate provision. These findings demonstrate that accessibility is shaped primarily by the spatial configuration of green spaces rather than by overall provision alone. The study highlights the importance of integrating urban morphology and climatic context into environmental justice assessments and urban green infrastructure planning in order to reduce spatial inequalities in access to urban nature.