Publications

Abstract <jats:p>Student-centred learning requires a variety of approaches, such as inquiry-based learning and the tackling of authentic and problem-based learning activities, to make the teaching and learning process more meaningful and to encourage students to participate more actively in class. The inquiry approach enables students to investigate solutions to real problems, awakening their need to ask questions, design and conduct research, collect and analyse data, interpret results and present them in a structured way. This study investigates the influence of an inquiry-based science education (IBSE) module on the development of oral and written communication skills among 10th grade students. The study is set in a secondary school context and focuses on a problem-based learning approach centred around gases and dispersions. A total of 111 students participated in this one-group post-assessment qualitative study, where evaluation rubrics were applied to assess students’ written and oral communication, focusing on correctness, clarity and mastery of scientific language. The results showed that the majority of students performed well in both written and oral tasks, demonstrating improved scientific communication skills. This suggests that IBSE, particularly in the context of secondary education, can be an effective approach to fostering students’ abilities to communicate scientific concepts. The study has implications for enhancing pedagogical practices and encourages further research on the long-term effects of IBSE on student learning.</jats:p>

Abstract An acid-base titrator connected to the Internet was developed for conducting remote investigative experiments. The experiment was broadcasted in a high school senior classroom, with the presence of a facilitating teacher. The activity required students to determine the indicator present in the solution. To carry out the activity, students added acid or base to sweep the pH range from 0 to 14 and noted the corresponding coloration to the pH through video analysis. The results obtained were very satisfactory, both in the identification of the indicator and in the acceptance and engagement of the students in the activity.

Abstract <jats:p>Educators cannot overlook the affect’s potential for students’ educational success. In this study, affective analogies are proposed as a didactic resource to foster students’ affect for chemistry learning and positive attitudes towards the physics-chemistry subject. To examine the influence of the affective analogies on it, we grouped contents of this subject into three modules (Kinetic-molecular theory; Quantum model of the atom; Chemical elements and their isotopes) and developed analogies between chemistry and music for each (affective analogies), which were then compared to homologous undifferentiated analogies (familiar analogues without affective qualities in addition) and teaching strategies without analogies. An explanatory mixed-method design was used. Data were collected through questionnaires and interviews, with a convenience sample of 147 students attending the 7th grade of a middle school music course. The results show that the affective dimension of analogies promotes positive affect for learning at much higher levels than the familiar dimension. We proposed a mechanism through which this occurs. However, if analogies are familiar, it seems that their positive affective dimension is not as important for students’ learning levels. More than interesting, analogies should perhaps be non-aversive. As for attitudes towards physics-chemistry, teaching with affective analogies is the most beneficial strategy. This results from students’ perception that this teaching approach promoted positive affect for the study of physics-chemistry, compared to undifferentiated analogies and without analogies. Furthermore, it favoured learning and achievement in physics-chemistry, compared to the absence of analogies, because without analogies it is more difficult to understand abstract or difficult concepts.</jats:p>

Abstract New psychoactive substances (NPS) are designed to evade legal regulation while mimicking the effects of classic illicit drugs such as 3,4-methylenedioxymethamphetamine (MDMA). This category includes phenethylamine derivatives, such as the psychedelic 2C and NBOMe drugs. Given the lack of data regarding the toxicological profile of these substances, the goal of this study was to evaluate the neurotoxicity of 2C-I and 25I-NBOMe and explore their neurotoxic pathways. Lower EC50 values, in both NR uptake and MTT reduction assays in differentiated SH-SY5Y cells and primary rat cortical cultures, revealed that 25I-NBOMe is significantly more cytotoxic than 2C-I, likely due to its higher lipophilicity. Both drugs triggered severe mitochondrial dysfunction, characterized by decreased intracellular ATP levels and mitochondrial membrane depolarization, although no significant changes in intracellular ROS/RNS levels were observed. Additionally, 25I-NBOMe increased the intracellular Ca2* levels. Apoptosis was an observed mechanism of cell death for both drugs, as demonstrated by a significant increase in the number of cells undergoing early apoptosis (AnV+/PI-) and late apoptosis/necrosis (AnV+/PI+). However, only 2C-I induced autophagy and strongly triggered caspase-3 activation. This suggests that 2C-I induces caspase-3-dependent apoptosis, whereas 25I-NBOMe may also induce apoptosis through a caspase-3-independent pathway, possibly involving increased intracellular Ca2* levels and direct mitochondrial damage. These findings underscore the complex interplay between mitochondrial dysfunction, calcium dysregulation, and cell death pathways, highlighting the central role of mitochondria in the cytotoxicity of 2C-I and 25INBOMe.

Abstract Edaravone is one of the treatment options for Amyotrophic Lateral Sclerosis, but its therapeutic efficacy is limited due to the incapacity to cross the blood-brain barrier, as well as its short life span and poor stability, which is ultimately caused by its tautomerism in physiological condions. This work presents an overview about the use of several nanoformulations based on polymeric, protein, lipidic, or hybrid structure as suitable and stable drug delivery systems for encapsulating edaravone. We also evaluated the functionalization of nanoparticles with pegylated chains using the polyethylene glycol or tocopherol polyethylene glycol succinate and the possibility of preparing polymeric nanoparticles at different pH (7.4, 9, and 11). Edaravone was sucessfully encapsulated in polymeric, lipid-polymer hybrid, and lipidic nanoparticles. The use of higher pH values in the synthesis of polymeric nanoparticles has led to a decrease in nanoparticle size and an increase in the percentage of encapsulation efficiency. However, the resulting nanoformulations are not stable. Only polymeric and hybrid nanoparticles showed good stability over 80 days of storage, mainly at 4 degrees C. Overall, the nanoformulations tested did not show cytotoxicity in the SH-SY5Y cell line except the nanostructured lipid carrier formulations that showed some cytotoxicity possibly due to lipidic peroxidation. In conclusion, this work shows that edaravone can be encapsulated in different nanocarriers that could act as an interesting alternative for the treatment of Amyotrophic Lateral Sclerosis.

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 The multifaceted nature of the neurodegenerative diseases, as Alzheimer's disease (AD) and Parkinson's disease (PD) with several interconnected etiologies, and the absence of effective drugs, led herein to the development and study of a series of multi-target directed ligands (MTDLs). The developed RIV-IND hybrids, derived from the conjugation of an approved anti-AD drug, rivastigmine (RIV), with melatonin analogues, namely indole (IND) derivatives, revealed multifunctional properties, by associating the cholinesterase inhibition of the RIV drug with antioxidant activity, biometal (Cu(II), Zn(II), Fe(III)) chelation properties, inhibition of amyloid-/3 (A/3) aggregation (self- and Cu-induced) and of monoamine oxidases (MAOs), as well as neuroprotection capacity in cell models of AD and PD. In particular, two hybrids with hydroxyl-substituted indoles ( 5a2 and 5a3) ) could be promising multifunctional compounds that inspire further development of novel anti-neurodegenerative drugs.

Abstract An experimental and computational thermochemical study is reported focus on the relationship between the energetic properties, the structural characteristics and the inherent reactivity of three thiothiadiazoles: 2-amino5-(methylthio-)-1,3,4-thiadiazole, 2-amino-5-(ethylthio-)-1,3,4-thiadiazole and 2-mercapto-5-methylthio-1,3,4thiadiazole. From the DSC measurements, the enthalpies of fusion and the respective onset temperatures were determined. The standard molar energies of combustion of the (alkylthio)-1,3,4-thiadiazoles were determined by rotating bomb combustion calorimetry. The corresponding standard molar enthalpies of sublimation, at T = 298.15 K, were derived from high-temperature Calvet microcalorimetry measurements and the study of the dependence of the compound's vapour pressures with the temperature, using the Knudsen-effusion technique. The combination of these experimental results enables the calculation of the standard molar enthalpies of formation in the gaseous state, at T = 298.15 K, which are discussed in terms of structural contributions. The latter property was also determined from high-level ab initio molecular orbital calculations at the G3(MP2)//B3LYP level of theory. The computed values are in good agreement with the experimental ones. In addition, a conformational and tautomeric study was conducted using the same approach, in order to provide insight on the amino/imino and thiol/thione tautomerism of the compounds studied. The amino form predominates in aminothiadiazoles, while the thione form prevails in mercaptothiadiazole. Moreover, the relative thermodynamic stability of each compound was also evaluated showing that in both solid and gas phases, the most stable species is the mercaptothiadiazole (in its thione form). The thermochemical results of the (alkylthio)-1,3,4-thiadiazoles show a good agreement with the NBO (natural bond orbitals) analysis results.