Publications

Abstract <jats:p>The I SEA project aimed at the development of a non-obtrusive, valid and replicable method to evaluate audience attitudes about science communication projects through an immersive virtual reality environment that can improve exhibitions while educating and empowering citizens. To achieve the objectives of this highly complex, highly interdisciplinary, and innovative project, a permanent articulation of the scientific approach with the technical and design development took place, aiming the construction of the non- invasive evaluation method. Because it is an intricate project, it required constant iterations and interactions among the team members. So, we’ve learned somehow to consider limitations as engines for developing the project, instead of seeing them as obstacles.</jats:p>

Abstract Contextualized and socially relevant hands-on activities are an effective way to promote students' involvement in the construction of knowledge. Considering the UN's 2030 Agenda for Sustainable Development, the preservation of water resources is crucial for the sustainable development of a country. Therefore, the PVC project was implemented in the context of water quality monitoring. There were 440 students and 9 chemistry teachers involved. A low-cost portable pedagogical kit was developed in order to determine the temperature, turbidity, pH, concentration of nitrates and nitrites, percentage of dissolved oxygen, salinity, and presence of microplastics in coastal water samples. The results indicate that the hands-on activities have contributed to the learning of chemical contents related to water quality parameters. Finally, the commitment, motivation, and autonomy of the participating students should be highlighted.

Abstract Emergence and expansion of frequent multidrug-resistant (MDR) major Salmonella clones/serotypes has been a significant threat in the last years. Metal compounds, such as copper, commonly used in animal-production settings, have been pointed out as possible contributors for the selection of such strains/clones. However, the scarcity of studies limits our understanding of the impact of other metal environmental contaminants as arsenic (used in insecticides/herbicides/coccidiostats). We analysed arsenic tolerance (AsT) dispersion by phenotypic and genotypic (PCR/sequencing/I-CeuI/S1/XbaI-PFGE/hybridization) assays among Salmonella with diverse epidemiological and genetic backgrounds. Then, to better understand ars operon genetic contexts, the whole genome of five representative strains was sequenced. We found a high dispersion of ars operons conferring AsT, especially among copper-tolerant and relevant serotypes/clones related to pig-production setting. The acr3-type was found dispersed in the chromosome of diverse serotypes, including the emergent S. Rissen. Conversely, arsBII was almost confined to the MDR ST34 European clone of S. Typhimurium/S. 4,[5],12:i:-, always along with copper/silver tolerance sil + pco clusters in an integrative conjugative element. These data suggest that AsT is an essential adaptive feature for the ecological success of these epidemic clones/serotypes and alerts for global strategies to reduce arsenic-based compounds' impact thus preventing environmental/food contamination with frequent MDR foodborne pathogens.

Abstract This paper focuses on the problematic role of digital tools in STEM activities for Physics teaching. A group of 47 teachers of Physics and Chemistry, from middle and secondary education, attended a continuous professional development training course during the academic year 2019/2020 that aimed to promote the development, adaptation, and implementation of STEM activities, centered on various topics in Physics (sound, electricity, kinetic and potential energy, mass and weight, gravitational pendulum and free fall) in teachers’ practices. Most of the activities already had an integration proposal for digital tools. Results revealed that teachers’ options range from adding specific and unspecific tools to implement STEM activities. In most cases, they only replace other non-digital tools. This work contributes to foster the action and reflection related to teachers’ knowledge and experience to introduce digital tools productively, amplify their options, and explore other related areas. © 2021, Springer Nature Switzerland AG.

Abstract The standard (p degrees =0.1 MPa) molar enthalpies of formation of orotic and isoorotic acids, in the crystalline phase, were derived from the respective standard massic energies of combustion measured by static bomb combustion calorimetry, in oxygen, at T = 298.15 K, as -821.7 +/- 1.1 kJ mol(-1) and -838.3 +/- 1.9 kJ mol(-1), respectively. The molecular structure and conformational behaviour of orotic and isoorotic acids were studied by theoretical calculations and the standard gas-phase molar enthalpies of formation were derived using an appropriate set of working reactions. Sublimation enthalpies, at the reference temperature T = 298.15 K, were estimated from difference between crystalline and gaseous enthalpies of formation and from statistically-based interaction indices derived from molecular surface electrostatic potentials.

Abstract Featured Application This is a contribution for enlarging the thermodynamic database of organic compounds and ketone derivatives. These data are very relevant to controlling experimental investigations to produce value-added chemical products from biomass. Moreover, the knowledge from such data can be used in the development of schemes for the prediction of homologous properties of related compounds, in particular, modeling studies for the prediction of bio-oil composition. The energetic study of 6-hydroxy-1-indanone and 7-hydroxy-1-indanone was performed using experimental techniques and computational calculations. The enthalpies of combustion and sublimation of the two compounds were determined and allowed to derive the corresponding gas-phase standard molar enthalpies of formation. For this purpose, static-bomb combustion calorimetry and drop-method Calvet microcalorimetry were the experimental techniques used. Further, the enthalpy of fusion of each compound was obtained from scanning differential calorimetry measurements. Additionally, the gas-phase standard molar enthalpies of formation of these compounds were calculated through high-level ab initio calculations. The computational study of the molecular structures of the indanones was carried out and two possible conformers were observed for 6-hydroxy-1-indanone. Furthermore, the energetic effects associated with the presence of one hydroxyl group as a substituent on the benzenic ring of 1-indanone were also evaluated. Both experimental and theoretical methods show that 7-hydroxy-1-indanone is thermodynamically more stable than the 6-isomer in the gaseous phase and these results provide evidence for the existence of a strong intramolecular H-bond in 7-hydroxy-1-indanone. Finally, the intramolecular proton transfer in 7-hydroxy-1-indanone has been evaluated and as expected, it is not energetically favorable.

Abstract Sunscreens have been employed on daily skin care for centuries. Their role in protecting the skin from sun damage, avoiding accelerated photoaging and even limiting the risk of development of skin cancer is unquestionable. Although several chemical and physical filters are approved as sunscreens for human use, their safety profile is dependent on their concentration in the formulation which governs their acceptance by the regulatory agencies. A strategic delivery of such molecules should provide a UV protection and limit the skin penetration. Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) may offer an alternative approach to achieve a synergistic effect on the UV protection when loaded with sunscreens as particles themselves also have a UV light scattering effect. Besides, the lipid character of SLN and NLC improves the encapsulation of lipophilic compounds, with enhanced loading capacity. Silica nanoparticles have also been employed in sunscreen formulations. Due to the formed sol-gel complexes, which covalently entrap sunscreen molecules, a controlled release is also achieved. In the present work, we have developed a new sunscreen formulation composed of hybrid SLN-Silica particles loaded with octyl methoxycinnamate (Parsol (R) MCX), and their further incorporation into a hydrogel for skin administration. Hybrid SLN-silica particles of 210.0 +/- 3.341 nm of mean size, polydispersity below 0.3, zeta potential of ca. [7] mV, loading capacity of 19.9% and encapsulation efficiency of 98.3% have been produced. Despite the slight negative surface charge, the developed hybrid nanoparticles remained physicochemically stable over the study period. Turbiscan transmission profiles confirmed the colloidal stability of the formulations under stress conditions. The texture profile analysis of Parsol-SLN and Parsol-SLN-Si revealed semi-solid properties (e.g. adhesiveness, hardness, cohesiveness, springiness, gumminess, chewiness, resilience) suitable for topical application, together with the bioadhesiveness in the skin of pig ears. The non-irritation profile of the hybrid nanoparticles before and after dispersion into Carbopol hydrogels was confirmed by HET-CAM test.