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Relação estrutura–atividade em compósitos à base de cobre: correlação entre composição e atividade bactericida
(Universidade Federal de São Carlos, 2026-02-04) Savazi, Letícia Vieira; Mendonça, Vagner Romito de; https://lattes.cnpq.br/4270375873948823; https://orcid.org/0000-0003-2300-9959; https://lattes.cnpq.br/8518531749246881; https://orcid.org/0000-0002-0780-2896; Mendonça, Vagner Romito de Mendonça; Nogueira, André Esteves; Dalmaschio, Cleocir José; https://lattes.cnpq.br/4270375873948823; https://lattes.cnpq.br/9755377874560173; https://lattes.cnpq.br/5209978120430790; https://orcid.org/0000-0003-2300-9959; https://orcid.org/0000-0003-3320-7959; https://orcid.org/0000-0002-3773-5786
The phenomenon of antimicrobial resistance drives research into new materials, with copper-based composites showing promise due to their low cost and multiple bactericidal mechanisms of action. This study investigated the correlation between solvothermal synthesis parameters, structural composition, and antimicrobial activity of copper-based materials. A 23 factorial design was used to evaluate the influence of monoethanolamine (MEA) concentration (0.05 and 0.075 M), temperature (120 and 150°C), and reaction time (5 and 20 h). Structural characterization was performed by X-ray diffraction with phase quantification via Rietveld refinement and by HRTEM, while morphology was analyzed by SEM-FEG and optical properties by DRS. Considering the proportional nature of the phases, the data were treated by Compositional Data Analysis, complemented by ANOVA and linear regression. The relative proportions of CuO, Cu2O, and Cu0 varied widely among the experimental conditions, with Cu2O predominating in all tests (>58.8%), while CuO and Cu0 reached maximum values of 34.6% and 33.3%, respectively. ANOVA indicated that the MEA concentration was the main factor associated with phase variation, significantly influencing the formation of CuO and Cu0; for CuO, an interaction effect between MEA and temperature was also observed, while Cu2O showed greater sensitivity to synthesis time. In the case of Cu0, both the MEA concentration and reaction time were found to have an influence. Morphological characterization revealed hierarchical microspheres consisting of nanometric aggregates. HRTEM analysis indicated lattice fringes compatible with the crystallographic planes of Cu2O and CuO, as well as domains attributed to Cu0, confirming the coexistence of the phases identified by XRD. In the biological evaluation, the bactericidal halos ranged from 0 to 2.88 mm and the bacteriostatic halos from 0 to 7.77 mm, the latter being more frequent and extensive. A moderate positive correlation was observed between CuO and bactericidal effect (ρ = 0.48) and a negative correlation with Cu0 (ρ = −0.49). The synthesis routes showed repeatability between independent series, maintaining the majority phase in all tests, and the results indicate an association between compositional variation and biological response in the investigated system.
Autoagregados de lecitina e sais de bile na presença de carboximetilquitosana
(Universidade Federal de São Carlos, 2026-02-04) Bega, Brenda da Silva; Paula, Kelly Roberta Francisco Muruci de; https://lattes.cnpq.br/0422652925722673; https://orcid.org/0000-0001-6673-3280; https://lattes.cnpq.br/7821276415930391; https://orcid.org/0000-0003-2725-8821; Souza, Adriano Lopes de; Silva, Lucimara Lopes da; https://lattes.cnpq.br/4671885302437668; https://lattes.cnpq.br/4525151236562359; https://orcid.org/0000-0001-6593-8399
The modulation of self-associated systems by polymers plays a fundamental role in the development of colloidal formulations, enabling control over their rheological and structural properties. This work investigated the influence of carboxymethyl chitosan (CMQ) on systems formed by lecithin and the bile salts, sodium cholate (NaC), sodium deoxycholate (NaDC) or sodium taurodeoxycholate (NaTDC), in aqueous medium. CMQ was synthesized by three methodologies and characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The CMQ-M1 sample was selected for presenting the highest yield (52.75%), more intense bands associated with carboxymethyl groups, and higher crystallinity (55.60%). Binary bile salt/lecithin systems were prepared at 1:1 and 1:2 ratios, followed by the addition of CMQ-M1 at concentrations of 0.5, 1.0, and 2.0% (w/w). The influence of the polymer was evaluated by dynamic light scattering (DLS), zeta potential, and rheological assays. The results showed that CMQ interacts in a manner dependent on the chemical nature of the bile salt and the ratio between the components. The results demonstrated that the behavior of these systems is strongly dependent on the structural differences among the bile salts. In systems containing NaC, CMQ increased the magnitude of the zeta potential and altered aggregate size, indicating greater colloidal stability. In systems containing NaDC, it reduced the zeta potential, favoring aggregation and disruption of the viscoelastic network. In systems containing NaTDC, it resulted in high zeta potential values, structural reorganizations, and increased viscosity, especially at the 1:1 ratio, where 2% CMQ led to phase separation. Overall, the results demonstrate that CMQ is an efficient polymer for modulating the structural, rheological, and stability properties of lecithin- and bile salt-based colloidal systems. These findings indicate the potential of these systems for pharmaceutical applications, such as formulations and controlled drug delivery systems.
Digital competencies of teachers in elementary education: challenges and possibilities in the use of digital technologies
(Universidade Federal de São Carlos, 2026-02-04) Souza Paula , Rita de Cássia de; Furnival, Ariadne Chloe Mary; https://lattes.cnpq.br/1291482506649810; https://lattes.cnpq.br/0577381905919329
Objective: This article aims to identify and promote reflections on the challenges faced by elementary school teachers in the use of Digital Information and Communication Technologies (DICT) in their teaching practices. Theoretical Framework: The research is based on the investigation of teachers' digital skills, based on the European DigCompEdu framework, in line with Brazilian public policy: the Connected Education Innovation Program. Method: To this end, an exploratory-descriptive study was conducted using a mixed approach with qualitative and quantitative aspects. Snowball sampling was used to locate the research subjects, resulting in 47 teachers from the states of Minas Gerais and São Paulo who work in schools covered by the Program. Results and Discussion: The data revealed that, although there have been advances in technological integration policies, challenges and difficulties still persist, such as inadequate infrastructure, unstable connections, lack of technical support, and teacher resistance to the use of TDICs. Gaps were also identified in relation to continuing education and insecurity regarding the handling of digital resources. Research Implications: Therefore, in addition to investing in infrastructure, it is essential to expand continuing education policies planned in a way that respects the reality of teachers, encouraging innovative and critical pedagogical practices aligned with contemporary demands. Originality/Value: The more effective integration of TDICs into basic education therefore requires integrated strategies that consider the structural, technical, human, and training aspects of teaching practice.
Viabilização da Confecção de Moldes de Areia com Reaproveitamento da black dross de Alumínio
(Universidade Federal de São Carlos, 2026-02-04) Silva, Raphael Oliveira da; Mambrini, Giovanni Pimenta; https://lattes.cnpq.br/7723027354150918; https://orcid.org/0000-0001-8943-5876; https://lattes.cnpq.br/1795568000118715; https://orcid.org/0009-0005-2246-4302; Pontes, Fenelon Martinho Lima; Trivinho-Strixino, Francisco; https://lattes.cnpq.br/1159480346990821; https://lattes.cnpq.br/9740223649776400; https://orcid.org/0000-0001-6086-5303; https://orcid.org/0000-0002-0990-0270
For Known for over 200 years, aluminum has dominated the industrial, metalworking, food, and aerospace markets, thanks to its remarkable structural capacity and versatility. In the automotive sector, for example, it is highly demanded for its low density and high mechanical strength, which allows for the construction of lighter chassis for electric vehicles, offsetting the weight of the batteries. However, the processes for obtaining metallic aluminum generate a significant amount of waste. While the production of primary aluminum results in a slag called white dross, the production of secondary aluminum is responsible for generating black dross. This work aimed to enable the reuse of black dross (BD) in the manufacture of molds for metal casting. Samples of BD were collected at Alux do Brasil, in partnership with Companhia Brasileira de Alumínio (CBA). These were characterized by scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) and X-ray diffractometry (XRD). They underwent hydrometallurgical leaching processes in distilled water (ABD) or anhydrous glycerol (GBD) to dissolve NaCl and KCl salts. Percentages of ABD were incorporated into silica sand in samples named T10, T20, T25, T40, T50, and T50* in the presence of alkaline resin and pyridine catalyst. Uniaxial tensile tests were performed on the ABD samples. For field testing, a product was modeled using the 3D design software "Inventor". Next, a prototype made of acrylonitrile butadiene styrene (ABS) polymer was printed using CURA software and a 3D printer. A sand mold was made with the best condition sample, T25, into which an aluminum alloy was melted and poured. The product obtained by the silica sand mold casting process with incorporated black dross proved promising; the mold remained stable and showed good thermal and mechanical resistance to metallostatic pressure, allowing the possibility of applying this method in manufacturing processes for casting aluminum alloys.
Imune à fake news em saúde: o ensino, a formação em Enfermagem e o enfrentamento da desinformação sobre vacinas contra a COVID-19
(Universidade Federal de São Carlos, 2026-02-04) Carvalho Junior, Juranildo Alves de; Zuin, Antônio Álvaro Soares; https://lattes.cnpq.br/5543562307373287; https://orcid.org/0000-0002-6850-2897; https://lattes.cnpq.br/3074186130931943; https://orcid.org/0000-0003-3045-9640; Salim, Natalia Rejane; Ramos, Ellen Taline de; https://lattes.cnpq.br/1116654985699024; https://lattes.cnpq.br/8274331125625601; https://orcid.org/0009-0002-8086-5823
The COVID-19 pandemic intensified the circulation of misinformation and fake news about vaccines, posing significant challenges to public health and professional education. This study aimed to analyze how fake news related to COVID-19 vaccines are addressed in nursing education and to understand students’ perceptions of their preparedness to confront health misinformation in professional practice. This is a mixed-methods study, conducted with nursing students from a Brazilian public university. Data were collected through a structured questionnaire using Likert-scale items and semi-structured interviews. Quantitative data were analyzed using descriptive statistics, and qualitative data were examined through thematic analysis. The results indicate that students recognize the significant impact of fake news on vaccine hesitancy and express concern about the increase in preventable diseases. However, the findings also reveal that the topic is addressed in a fragmented and unsystematic manner during undergraduate education, with noticeable educational gaps and diverse teaching approaches. The study concludes that addressing vaccine-related misinformation in nursing education requires continuous pedagogical strategies that integrate theoretical foundations, health education, and risk communication, to strengthen professional autonomy and critical practice in the face of contemporary public health challenges.