Publications

Abstract <jats:p>Este artículo presenta una propuesta de secuencia didáctica dirigida a estudiantes de secundaria. Se propone la exploración de indicadores ácido-base naturales con el fin de caracterizar diferentes soluciones acuosas. Luego, los estudiantes se enfrentan a un escenario desafiante e investigativo: la adición de lejía a un refresco de cola resulta en una reacción química que también implica cambios de color. Basándose en el protocolo desarrollado, los estudiantes llevarán a cabo ensayos experimentales para determinar si el refresco de cola es un indicador ácido-base. Para explicar los resultados obtenidos, los estudiantes llevarán a cabo una investigación cuyas conclusiones llevarán a la introducción del tema de las reacciones de oxidación-reducción. Con esta propuesta se busca fomentar la participación activa de los estudiantes en la construcción de su aprendizaje a través de actividades prácticas y experimentales, utilizando materiales cotidianos para promover su autonomía y, al mismo tiempo, estimular la curiosidad científica y el desarrollo de habilidades esenciales para la educación del siglo XXI. Además, el conocimiento que este enfoque didáctico contribuye significativamente a una comprensión más profunda de los conceptos fundamentales de la Química, promoviendo reflexiones más profundas sobre su relevancia en la sociedad actual.</jats:p>

Abstract BackgroundRecent literature underscores the importance of programming in preparing students for the challenges of a technologically evolving society.PurposeThis study explores the integration of Arduino programming in a non-formal education context, considering its potential to promote interdisciplinary approaches - particularly in Physics and ICT subjects - and foster students' interest and motivation.SampleEighty Portuguese middle school students participated in the practical activity designed.Design and MethodsDuring the activity, fundamental concepts of electronics, circuits, and Arduino programming were introduced and explored. Participants completed a questionnaire regarding their interests, motivations, and experiences. The data were supplemented with field notes collected by the research team.ResultsFindings show significant student interest in exploring Arduino programming, despite facing challenges such as coding difficulties and limited familiarity with electronic components and circuits. Students expressed enthusiasm for engaging in future activities related to the topic and supported its interdisciplinary integration and they recognized its potential to improve learning outcomes and develop essential competencies and skills.ConclusionPositive indicators have emerged from this research regarding the implementation of this innovative approach, which could be transposed into a formal education context, such as Physics. This approach not only captivates students' interest but also empowers them to thrive in an ever-evolving technological landscape.

Abstract This study applies agenda-setting theory to examine how ocean-related topics are emphasized in Portuguese digital journalism. We analyze media content from three online newspapers - Expresso, P & uacute;blico, and Jornal de Neg & oacute;cios - between 2010 and 2023, focusing on themes such as deep-sea exploration and the Ocean Decade. Using text mining techniques, we identify dominant thematic priorities in media discourse, specifically the prominence of Economic, Political, Scientific, and Environmental themes. Our findings reveal a rising trend in ocean-related publications, with economic narratives being dominant, particularly in Jornal de Neg & oacute;cios, while P & uacute;blico places more emphasis on scientific and environmental discussions. The Ocean Decade is framed positively across all three outlets, whereas deep-sea mining is approached with a more cautious tone. By highlighting shifts in media emphasis, this study contributes to discussions on how journalistic coverage influences the visibility of ocean issues, reinforcing the role of the press in shaping the media agenda of environmental and scientific discourse.

Abstract Polypharmacological approaches have significant potential for the treatment of various complex diseases, including infectious bacteria-related diseases. Actually, multitargeting agents can achieve better therapeutic effects and overcome the drawbacks of monotherapy. Although multidrug multitarget strategies have demonstrated the ability to inactivate infectious bacteria, several challenges have been pointed out. In this way, multitarget direct ligands approaches appear to be a rational and sustainable strategy to combat antibiotic resistance. By combining different pharmacophores, antibiotic hybrids stand out as a promising application in the field of bacterial infections. These new chemical entities can achieve synergistic interactions that allow to extend the spectrum of action and target multiple pathways. In addition, antibiotic hybrids can reduce the likelihood of resistance development and provide improved chemical stability. It is worth highlighting that despite the efforts of the scientific community to discover new solutions for the most complex diseases, there is a significant lack of studies on biofilm-associated infections. This review describes the different polypharmacological approaches that can be used to treat bacterial infections with a particular focus, whenever possible, on those promoted by biofilms. By exploring these innovative approaches, we aim to inspire further research and progress in the search for effective treatments for infectious bacteria-related diseases, including biofilm-related ones. Significance Statement: The importance of the proposed topic lies in the escalating challenge of antibiotic resistance, particularly in the context of infectious bacteria-related infections. Polypharmacological approaches, such as antibiotic hybrids, represent innovative strategies to combat bacterial infections. By targeting multiple signaling pathways, these approaches not only enhance therapeutic effect but also reduce the development of resistance while improving the drug's chemical stability. Despite the urgent need to combat bacterial infectious diseases, there is a notable research gap, in particular in biofilmrelated ones. This review highlights the critical importance of exploring polypharmacological approaches with the aim of motivating further research and advances in effective treatments for infectious bacteria, including biofilm related infections.

Abstract Antimicrobial photodynamic inactivation (aPDI), using photosensitisers in combination with antibiotics, is a promising multi-target strategy to address antibiotic resistance, particularly in wound infections. This study aimed to elucidate the antibacterial mode of action of combinations of berberine (Ber) or curcumin (Cur) with selected antibiotics (Ber-Ab or Cur-Ab) under blue light irradiation (420 nm) against Staphylococcus aureus, including methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains. Multiple physiological parameters were assessed using complementary assays (fluorometry, epifluorescence microscopy, flame emission and atomic absorption spectroscopy, zeta potential, flow cytometry, and the plate agar method) to examine the effect on ROS production, membrane integrity, DNA damage, motility and virulence factors of S. aureus. Results indicated that blue light photoactivated Ber-Ab and Cur-Ab combinations led to substantial ROS generation, even at low concentrations, causing oxidative stress that severely impacted bacterial membrane integrity (approximately 90 % in MRSA and 40 % in MSSA). Membrane destabilization was further confirmed by elevated intercellular potassium release (approximate to 2.00 and 2.40 mu g/mL in MRSA and MSSA, respectively). Furthermore, significant DNA damage was observed in both strains (approximate to 50 %). aPDI treatment with blue light also reduced S. aureus pathogenicity by impairing motility and inhibiting key virulence factors such as proteases, lipases, and gelatinases, all of which play key roles in the infectious process. Overall, Ber-Ab combinations demonstrated the highest efficacy across all parameters tested, highlighting for the first time the multi-target therapeutic potential of this phytochemical-based aPDI strategy to combat antibiotic-resistant S. aureus infections and improve wound infection treatment outcomes.

Abstract The ability of Salmonella enterica subsp. enterica to persist and form biofilms on different surfaces can constitute a source of food contamination, being an issue of global concern. The objective of this study was to understand the biofilm formation profile of 14 S. enterica strains among different serovars and sources and to evaluate the ability of essential oil (EO) components (carveol, citronellol, and citronellal) to disinfect the biofilms formed on stainless steel and polypropylene surfaces. All the strains were able to form biofilms with counts between 5.34 to 6.78 log CFU cm(-2). Then, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EO components were evaluated on two selected strains. All compounds inhibited the growth of Salmonella Typhimurium (strain 1; MIC = 800-1000 mu g ml(-1)) and Salmonella Enteritidis (strain 5; MIC = 400-1000 mu g ml(-1)) and only carveol showed bactericidal activity against strains 1 and 5 (MBC = 1200 mu g ml(-1)). Biofilms were exposed to the EO components at 10 x MIC for 30 min and polypropylene surfaces were more difficult to disinfect showing reductions between 0.9 and <1.2 log CFU cm(-2). In general, the S. enterica biofilms demonstrated a significant tolerance to disinfection, demonstrating their high degree of recalcitrance on food processing surfaces.

Abstract Hydroponics is an advanced agricultural technique that involves growing plants without soil. Instead, plants are cultivated in a nutrient-rich water solution that provides all the essential minerals they need to thrive, allowing plants to grow either with their roots directly in the solution or supported by inert substrates like pine bark, coconut husk fiber, and rice husk. The solid waste generated from hydroponic cultivation is valuable due to its low cost, abundance, biodegradability, and renewability. These residues are rich in lignocellulosic materials, which can be extracted and refined to produce cellulose and nanocellulose (NC). In this work, cellulose and nanocellulose were extracted from residues of coconut husk fiber and a mixture of pine bark and coconut husk fiber, used in tomato and strawberry hydroponics, respectively. The residues were ground, washed, and chemically treated to obtain cellulose and NC. The chemical process involved several stages: (i) acid treatment, alkaline treatment, and bleaching to isolate cellulose, and (ii) acid hydrolysis followed by ultrasonication to obtain NC. Both materials underwent characterization using various techniques such as TGA, DSC, XRD and FTIR-ATR, which confirmed very low levels of lignin and hemicellulose. Morphological characterization through SEM revealed the presence of micro- and nano-crystals in the cellulose and NC samples, respectively, highlighting the effectiveness of the extraction method. The high purity and quality of the extracted materials make them competitive with commercially available products, suitable for applications in healthcare, food packaging, and automotive industries, while supporting recycling and reuse principles.

Abstract Extensive research has focused on films formed by pure ionic liquids (ILs). However, growing interest in IL mixtures and their synergistic properties presents new opportunities for targeted applications and fundamental scientific investigations. This study explores the morphology of films composed of mixtures of two ILs, [C2C1im][OTf] and [C8C1im][OTf], co-deposited via physical vapor deposition (PVD)/vacuum thermal evaporation. The primary objective was understanding how varying the IL ratio influences droplet formation, surface coverage, and overall film structure. Thin-film growth was examined on glass substrates coated with indium tin oxide (ITO) and ITO/glass surfaces coated with metallic films (Au and Ag). Film morphology was characterized using optical and high-resolution scanning electron microscopy (SEM), while elemental composition was analyzed via X-ray photoelectron spectroscopy (XPS). The results show that IL mixture morphology is strongly influenced by both IL composition and substrate type. Increasing [C8C1im][OTf] content led to larger microstructures due to improved wetting, particularly on Au surfaces, resulting in nearly fully coalesced films. Metallic surfaces near ITO significantly impacted droplet behavior, with ILs exhibiting a strong affinity for metals, especially when the long-chain IL dominated the mixture. The IL-assisted crystallization of rubrene, a high-performance organic semiconductor (OSC) that typically exhibits poor crystallinity when deposited via PVD, highlights the potential of IL mixtures to enhance organic film quality. X-ray diffraction (XRD) confirmed that [C2C1im][OTf] and [C8C1im][OTf] mixtures significantly improved rubrene crystallinity, demonstrating their potential to create an optimal environment for OSC solubility and crystallization.

Abstract This work integrates Talanquer's model of the chemical knowledge space, focusing on developing an educational animation and a virtual/augmented reality object. We designed the animation concerning bimolecular nucleophilic substitution, offering a multifaceted learning approach incorporating theoretical calculations and three-dimensional molecular modeling. This method facilitates a deeper understanding of complex chemical reactions and engages students in a more immersive and interactive learning experience. The use of advanced software like Blender 3D for 3D editing and animating, as well as Gaussian for generating accurate structures and electronic configurations, along with a well-thought-out pedagogical framework, allows for a higher level of abstraction in depicting how molecules interact. Our approach enhances the quality of the lessons and helps students gain a better understanding of chemistry's conceptual and practical aspects. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Abstract This study investigates spatial distribution and chemical elemental composition screening in soils in Rome (Italy) using X-ray fluorescence analysis. Fifty-nine soil samples were collected from various locations within the urban areas of the Rome municipality and were analyzed for 19 elements. Multivariate statistical techniques, including nonlinear mapping, principal component analysis, and hierarchical cluster analysis, were employed to identify clusters of similar soil samples and their spatial distribution and to try to obtain environmental quality information. The soil sample clusters result from natural geological processes and anthropogenic activities on soil contamination patterns. Spatial clustering using the k-means algorithm further identified six distinct clusters, each with specific geographical distributions and elemental characteristics. Hence, the findings underscore the importance of targeted soil assessments to ensure the sustainable use of land resources in urban areas.