Publications

Abstract Undergraduate arts and design programs have been incorporating computing education into their curricula. Through a documentation analysis of the first cycle (i.e., bachelor’s) curricula of fered by the Portuguese public education subsystem in the 2018-19 academic year, we identified 40 programs from diverse artistic and design areas, attended by around 5,600 students, which contained at least one course covering computer programming. In a subsequent qualitative analysis of the syllabi of those 128 courses we had identified as relevant, we characterized the objectives, the contents, and the teaching and assessment methods for computing in higher arts education. In the face of the skepticism the literature expresses regarding the validity and robustness of brief approaches to computing, we found most undergraduate programs dedicate few courses or credits (i.e., ECTS) to the topic. We also found programs that introduce the topic late in the curriculum, at a stage when it is likely to meet less dedication from the students. At course level, we note the prevalence of the objective of granting autonomous learning skills to students, which often translates into contents too broad to approach in a non-superficial way. Moreover, we alert to the use of project-based assessment methods in ways that do not assure learning of the contents. With this article we hope to provide an overview of the current situation and contribute to a reflection and a debate about the relevance and the way computing is covered within arts and design education. © (2024), (Emerson de Pietri). All Rights Reserved.

Abstract Activities with Parents on the Computer are pedagogical tasks based on socially relevant disciplinary content with the aim of establishing the school-home connection and collaboration between parents and students, to promote digital literacy and literacy in a specific domain. This article addresses a study that aimed to investigate the contribution of the Activity with Parents on the Computer "NanoAPC", both for the development of knowledge of 8th grade students about the area of nanotechnology, and to raise awareness among parents/guardians for the said area. The activities were proposed in a formal learning environment, the school, but were carried out at home by the student and one of the parents or guardian. NanoAPC intended to help students to learn Chemistry contents contextualized with the advances and applications of nanotechnology in society, from a socio-scientific perspective. A quasi-experimental research plan was implemented, with 58 students and 58 parents/guardians participating. Students were divided into two experimental conditions that were tested: groups 1 and 2, subject to NanoAPC, but with a different initial intervention, and group 3, subject to an activity sheet. All groups were subjected to a questionnaire as a pre-test and post-test, respectively before and after the intervention. The results, resulting from the analysis of the pre-test and post-test and the answers given in the respective activity sheets, show that the students in groups 1 and 2 showed a significant improvement in their knowledge of nanotechnology compared to those in group 3. We conclude that the NanoAPC digital resource is useful for teachers who show an interest in addressing nanotechnology but who have time constraints due to curriculum management. In addition, it promotes the parent-student-computer triangulation and, consequently, raises parents' awareness of this area. © 2024 Universidade Federal do Rio Grande do Sul, Instituto de Fisica. All rights reserved.

Abstract Nanocomposites have garnered attention for their potential as catalysts in electrochemical reactions vital for technologies like fuel cells, water splitting, and metal-air batteries. This work focuses on developing threedimensional (3D) nanocomposites through aqueous phase exfoliation, non-covalent functionalization of building blocks with surfactants and polymers, and electrostatic interactions in solution leading to the nanocomposites assembly and organization. By combining molybdenum disulfide (MoS2) layers with graphene nanoplatelets (GnPs) to form a binary 2D composite (MoS2/GnP), and subsequently incorporating multiwalled carbon nanotubes (MWNTs) to create ternary 3D composites, we explore their potential as catalysts for the oxygen reduction reaction (ORR) critical in fuel cells. Characterization techniques such as X-ray photoelectron spectroscopy, scanning electron microscopy, and X-ray diffraction elucidate material composition and structure. Our electrochemical studies reveal insights into the kinetics of the reactions and structure-activity relationships. Both the (MoS2/GnP)-to-MWNT mass ratio and nitrogen-doping of GnPs (N-GnPs) play a key role on the electrocatalytic ORR performance. Notably, the (MoS2/N-GnP)/MWNT material, with a 3:1 mass ratio, exhibits the most effective ORR activity. All catalysts demonstrate good long-term stability and methanol crossover tolerance. This facile fabrication method and observed trends offer avenues for optimizing composite electrocatalysts further.

Abstract Malaria is one of the big three global infectious diseases, having caused above two hundred million cases and over half a million deaths in 2020. The continuous demand for new treatment options prioritizes the cost-effective development of new chemical entities with multi-stage antiplasmodial activity, for higher efficacy and lower propensity to elicit drug-resistant parasite strains. Following up on our long-term research towards the rescue of classical antimalarial aminoquinolines like chloroquine and primaquine, we have developed new organic salts by acid-base pairing of those drugs with natural bile acids. These antimalarial drug-derived bile salts were screened in vitro against the hepatic, blood and gametocyte stages of Plasmodium parasites, unveiling chloroquine bile salts as unprecedented triple-stage antiplasmodial hits. These findings pave a new pathway for drug rescuing, even beyond anti-malarial and other anti-infective drugs. Malaria is one of the big three global infectious diseases, with the heaviest toll on human lives in low-to-middle income countries. Cost-effective antimalarial drugs with multi-stage action remain an unmet and urgent need in global healthcare.

Abstract In this investigation, Co-, Ni- and Cu-doped ZnO nanoparticles were prepared using precipitation methods. The characterization of the as-prepared nanomaterials was carried out using XRD, FT-IR, DRS, XPS and SEM. The XRD analysis showed that the insertion of foreign metal ions into the matrix of ZnO caused a slight shift of the positions of (100), (002) and (101) diffraction peaks of ZnO towards the lower 2 theta, by comparison with pure ZnO. The DRS results showed that Co-doped ZnO nanoparticles absorb wavelengths higher than 400 nm. The estimated band gaps (eV) were 2.48, 3.17 and 3.14 for 10 %Co-ZnO, 10 %Ni-ZnO and 10 %Cu-ZnO respectively. The XPS results showed the existence of two valence states for Co and Ni (Co2+/Co3+ and Ni2+/Ni3+) while Cu exists in the form of Cu2+. The photocatalytic efficiency was evaluated under UV and visible irradiations in aqueous solution using methyl orange (MO) as an organic pollutant probe molecule. The results showed that, under visible light, the MO degradation increased significantly by doping ZnO (10 %Co-ZnO: 33.2 %; 10 %NiZnO: 19.8 % and 10 %Cu-ZnO: 52.5 %) by comparison with undoped ZnO (9.3 %). The important increase in photocatalytic activity observed for the doped ZnO by comparison with pure ZnO, particularly for 10 %Cu-ZnO, has been linked to a synergistic effect of both the band gap narrowing and the increase in the lifetime of photogenerated charge carriers.

Abstract Cancer is still one of the most challenging diseases to treat, making the pursuit for novel molecules with potential anticancer activity an important research topic. Herein, we have performed a comparative investigation into the anticancer activity of analogs of marine coelenterazine and coelenteramine. The former is a well-known bioluminescent substrate, while the latter is a metabolic product of the resulting bioluminescent reaction. While both types of analogs showed anticancer activity toward lung and gastric cancer cell lines, we have obtained data that highlight relevant differences between the activity of these two types of compounds. More specifically, we observed relevant differences in structure-activity relationships between these types of compounds. Also, coelenteramine analogs showed time-dependent activity, while coelenterazine-based compounds usually present time-independent activity. Coelenterazine analogs also appear to be relatively safer toward noncancer cells than coelenteramine analogs. There was also seen a correlation between the activity of the coelenterazine-based compounds and their light-emission properties. Thus, these results further indicate the potential of the marine coelenterazine chemi-/bioluminescent system as a source of new molecules with anticancer activity, while providing more insight into their modes of action.

Abstract In a society heavily influenced by technological advancements, developing scientific and technological literacy among young people is essential. Along these lines, this research describes a STEM activity developed to promote the teaching of chemistry content related to the solubility of potassium nitrate in water. It also facilitated the mastery of technological skills such as programming Arduino microcontrollers and using Microsoft Excel as tools for automatic data acquisition and analysis. Eighty pre-university Chemistry students participated in this research. This pedagogical approach was divided into three main stages: (1) preliminary research on components used in the experimental apparatus; (2) introduction to the assembly of electrical circuits and Arduino programming; (3) experimental investigation of the dependence of potassium nitrate solubility on temperature. The activity allowed the students to successfully achieve the proposed chemistry learning objectives while mobilizing other scientific and technological knowledge and skills. Despite the students' limited prior knowledge of programming and electronics, as well as their limited proficiency in data analysis software, the integration of programming in the Chemistry class proved to be a differentiating factor with a highly positive impact, particularly in terms of motivation and interest among most students.

Abstract Emerging threats to human health require a concerted effort to search for new treatment therapies. One of the biggest challenges is finding medicines with few or no side effects. Natural products have historically contributed to major advances in the field of pharmacotherapy, as they offer special characteristics compared to conventional synthetic molecules. Interest in natural products is being revitalized, in a continuous search for lead structures that can be used as models for the development of new medicines by the pharmaceutical industry. Chromone and chromanones are recognized as privileged structures and useful templates for the design of diversified therapeutic molecules with potential pharmacological interest. Chromones and chromanones are widely distributed in plants and fungi, and significant biological activities, namely antioxidant, anti-inflammatory, antimicrobial, antiviral, etc., have been reported for these compounds, suggesting their potential as lead drug candidates. This review aims to update the literature published over the last 6 years (2018-2023) regarding the natural occurrence and biological activity of chromones and chromanones, highlighting the recent findings and the perspectives that they hold for future research and applications namely in health, cosmetic, and food industries.

Abstract This work presents a comprehensive study exploring the thermodynamics of the solid phase of a series of phenylimidazoles, encompassing experimental measurements of heat capacity, volatility, and thermal behavior. The influence of successive phenyl group insertions on the imidazole ring on thermodynamic properties and supramolecular behavior was thoroughly examined through the evaluation of 2-phenylimidazole (2-PhI), 4-phenylimidazole (4-PhI), 4,5-diphenylimidazole (4,5-DPhI), and 2,4,5-triphenylimidazole (2,4,5-TPhI). Structural correlations between molecular structure and thermodynamic properties were established. Furthermore, the investigation employed UV-vis spectroscopy and quantum chemical calculations. Additive effects arising from the introduction of phenyl groups were found through the analysis of the solid-liquid and solid-gas equilibria, as well as heat capacities. A good correlation emerged between the thermodynamic properties of sublimation and the molar volume of the unit cell, evident across 2-PhI, 4,5-DPhI, and 2,4,5-TPhI. In contrast to its isomer 2-PhI, 4-PhI exhibited greater cohesive energy due to the stronger N-HN intermolecular interactions, leading to the disruption of coplanar geometry in the 4-PhI molecules. The observed higher entropies of phase transition (fusion and sublimation) are consistent with the higher structural order observed in the crystalline lattice of 4-PhI.

Abstract Carbon materials are readily available and are essential in energy storage. One of the routes used to enhance their surface area and activity is the decoration of carbons with semiconductors, such as amorphous TiO2, for application in energy storage devices.