Universidade Federal de Santa Maria

This study investigated the combined effects of drying method, wall material ratio and concentration, and green tea extract addition on the technological performance and simulated gastrointestinal survival of microcapsules containing Lactobacillus acidophilus . Microcapsules were produced by freeze-drying and spray-drying using different maltodextrin and gum arabic ratios and evaluated for viability, yield, encapsulation efficiency, storage stability, structural characteristics, and resistance under simulated gastrointestinal conditions. Freeze-drying preserved probiotic viability more effectively than spray-drying. Post-encapsulation counts after freeze-drying ranged from 8.23 to 8.54 log CFU/g, with encapsulation efficiencies above 93%. In contrast, spray-dried samples showed lower counts (7.59-8.30 log CFU/g) and reduced yields (42-62%), despite efficiencies exceeding 86%. Under simulated gastrointestinal conditions, free cells showed a reduction of approximately 3.7 log units, resulting in final viability of about 61%. Freeze-dried formulations with maltodextrin-gum arabic ratios (8:2 and 5:2) maintained survival rates above 90% throughout gastrointestinal stages, whereas spray-dried samples exhibited lower ileal counts (4.6–5.7 log CFU/g). The addition of green tea extract further improved probiotic survival, particularly in optimized freeze-dried systems. Fourier transform infrared spectroscopy and scanning electron microscopy supported the structural interpretation, indicating improved matrix vitrification, reduced structural defects, and enhanced oxygen barrier properties in polymer formulations. Although encapsulation efficiency remained high after processing, simulated gastrointestinal exposure significantly reduced viable counts, highlighting the importance of matrix composition in controlling protection. Overall, probiotic performance depended on the integrated interaction between drying method, polymer ratio, and antioxidant incorporation, providing practical formulation criteria for robust probiotic ingredients with enhanced gastrointestinal resistance. • Optimized maltodextrin–gum arabic ratios ensured >90% survival during digestion. • Freeze-dried capsules formed amorphous, low-aw matrices with high probiotic stability. • Encapsulation increased resistance to heat, pH, salt, and osmotic food stresses. • Integrated processing–digestion–storage assessment guides functional food design.

This study investigates the effects of temperature and pressure on the conversion rate and efficiency of sweet sorghum bagasse during subcritical water hydrolysis. Batch experiments were carried out at 200, 240, and 280 °C under autogenous pressure (liquid–vapor equilibrium) and induced pressure (100 bar), allowing direct kinetic comparison under identical thermal conditions. At 200 °C, induced pressure significantly accelerated biomass conversion, resulting in faster depolymerization of cellulose and hemicellulose, a 25% higher peak cellulose conversion, and attainment of maximum biomass accessibility approximately 50 min earlier than under autogenous pressure. Under autogenous pressure at this temperature, conversion rates were lower and secondary products such as organic acids were favored. At 240 °C, biomass conversion proceeded rapidly and similarly under both pressure conditions, producing the highest fermentable sugar yields and indicating efficient carbohydrate conversion with limited degradation. At 280 °C, conversion rates were dominated by temperature, with overall biomass conversion efficiency reaching approximately 80% within 10–15 min. However, prolonged reaction times led to a decrease in measured conversion due to thermal degradation of sugars and formation of secondary products. Across the studied conditions, pressure influenced conversion rates only at the lowest temperature, while temperature was the dominant parameter governing reaction kinetics at 240 and 280 °C. These results demonstrate that pressurization above water saturation is unnecessary at elevated temperatures, enabling simplified operation with reduced energy demand and capital costs. • 240 °C maximizes fermentable sugar release. • Pressure affects hydrolysis only at 200 °C, not at 240/280 °C. • 280 °C subcritical hydrolysis degrades HMF and furfural, lowering yield. • Hydronium ions catalyze hydrolysis, peaking at 240 °C. • Saturated pressure cuts costs while maintaining high-temperature efficiency.

Genetically modified (GM) cotton expressing Bacillus thuringiensis ( Bt ) toxins is an important tool for managing lepidopteran pests in Brazil; however, its efficacy against Spodoptera frugiperda (J. E. Smith) is reduced because of widespread resistance to Bt maize. Here, we evaluated the performance of Bt cotton and insecticides against Vip3Aa20-resistant, Vip3Aa20-susceptible, and heterozygous strains. The study included two phases: (i) assessment of larval survival and development on Cry1Ac/Cry2Ab2/Vip3Aa20, Cry1Ac/Cry2Ab2, and non- Bt cotton, and (ii) evaluation of the efficacy of thiodicarb and flubendiamide against L2 and L4 larvae surviving on these cotton types. Survival patterns on Bt cotton differed among strains: resistant larvae reached adulthood on both Bt cotton types, albeit with prolonged developmental time; heterozygous larvae survived only on Cry1Ac/Cry2Ab2 cotton; and susceptible larvae died in early instars on both Bt technologies. All strains showed high survival on non- Bt cotton. Thus, Cry1Ac/Cry2Ab2/Vip3Aa20 cotton controlled susceptible and heterozygous larvae completely but allowed substantial survival of resistant larvae, whereas Cry1Ac/Cry2Ab2 cotton was effective mainly against susceptible insects. Thiodicarb caused consistently high mortality of L2 and L4 larvae, including Bt and non- Bt survivors, whereas flubendiamide showed limited lethality. Although combining either type of Bt cotton with thiodicarb improved overall control, it did not fully suppress resistant larvae. These results demonstrate that Vip3Aa20 resistance in S. frugiperda reduces the efficacy of current Bt cotton technologies and underscore the need to integrate Bt cotton with insecticides for the management of this pest. • Vip3Aa20 resistance in Spodoptera frugiperda reduces Bt cotton efficacy. • Cry1Ac/Cry2Ab2/Vip3Aa20 cotton controls susceptible and heterozygous, but not resistant larvae. • Cry1Ac/Cry2Ab2 cotton controls only susceptible larvae. • Thiodicarb controls Vip3Aa20-resistant larvae across instars in Bt and non- Bt cotton. • Flubendiamide shows reduced control of resistant and heterozygous in both cotton types.

To evaluate the biomechanical behavior of bilayer crowns with traditional and modified core designs using fatigue survival testing and finite element analysis (FEA), aiming a suitable rehabilitation for the anterior teeth area. Forty-five crowns were manufactured, according to the following groups: CC (conventional core), MCS (modified core/stratified veneer) and MCM (modified core/machined veneer). Cores were machined (lithium disilicate); veneers of CC and MCS groups were made through stratification (fluorapatite), and veneers of MCM group were also machined (leucite). Next, the crowns were cemented using resin cement (Variolink Esthetic LC) over full crown preparations made of epoxy resin and then subjected to cyclic fatigue test. After mechanical testing two events were considered: the presence of crack and/or chipping (event 1) and catastrophic failure of the crown (event 2). The average load to failure and number of cycles to failure in which events 1 and 2 occurred were used to perform the survival analysis according to Kaplan-Meier and Log-Rank (Mantel-Cox; 95%). Fracture marks and failure mode of the crowns were evaluated and classified by optical stereomicroscope and scanning electron microscope. Finally, FEA was performed to evaluate the stress distribution on the crowns. Fatigue test results showed that considering event 1 the groups with modified cores (MCS: 1020N and MCM: 913N) presented higher average loads and number of cycles to failure than the group CC (773N). Considering event 2 all groups showed similar fatigue performance (∼1028N). FEA results evidenced higher stress concentration at the load application area, with a slight stress at the cervical margin of the crowns regardless the group. Modified core designs improved resistance to initial veneer damage without compromising catastrophic failure performance. Stress distribution patterns supported the mechanical findings, indicating favorable biomechanical behavior.

Yerba mate (Ilex paraguariensis A. St.-Hil.) is a South American native plant whose leaves are used to produce mate, a traditional hot water infusion. The species is rich in secondary metabolites of economic interest and grows naturally in acidic, low-fertility soils where aluminum (Al) is highly bioavailable. However, the influence of Al on secondary metabolism and infusion composition is poorly understood. We cultivated I. paraguariensis in a hydroponic system with increasing Al concentrations. Plant morphology and photosynthesis parameters were not affected, while reactive oxygen species levels and antioxidant enzymatic activity increased. The concentration of secondary metabolites in the infusion, such as caffeine, chlorogenic acid, and flavonoids, exhibited compound-specific changes. Aluminum was detected in the infusion, but its concentration remained similar across treatments, suggesting that external Al supply does not necessarily transfer to the beverage. These findings indicate that I. paraguariensis is Al tolerant, and that Al modulates yerba mate oxidative metabolism, altering infusion composition without impairing physiological parameters.

Wild fish populations face growing threats from anthropogenic activities, climate change, and natural disasters. Aquatic germplasm banking is a vital strategy for preserving genetic diversity and supporting sustainable aquaculture. This study proposes a sequential, decision-guided framework for developing species-specific sperm cryopreservation protocols, applied here to the endangered Pogonias courbina, listed as endangered in Brazil and vulnerable by the IUCN. A series of experiments was conducted to identify optimal conditions for thawing (26°C for 14s), equilibration time (10min), extenders (HBSS, 3% glucose, 5% glucose), and both permeable (dimethyl sulfoxide, propylene glycol, dimethylformamide, ethylene glycol) and non-permeable cryoprotectants (glucose, fructose, sucrose, trehalose, skimmed powdered milk, egg yolk). Sperm quality was assessed using Computer-Assisted Sperm Analysis (CASA). Three treatments with the highest post-thaw motility (MOT) were selected to fertilize oocytes from two hormonally-induced females. No significant difference was observed between sperm from wild and farmed males. The best kinetic parameters and fertilization rates were obtained using the combination of HBSS +10% DMSO +5% egg yolk (MOT: 71.8%). Based on these findings, we propose practical recommendations regarding extender selection, equilibration time, cryoprotectant combinations, and thawing conditions that support high post-thaw viability and successful fertilization. This is the first study to report successful artificial reproduction of P. courbina using cryopreserved sperm, establishing a reproducible protocol that can be applied for captive breeding, restocking, and germplasm banking. The proposed framework offers a generalizable approach for developing cryopreservation protocols in fish species.

To assess how resin cement viscosity and thickness influence the static shear bond strength (s-SBS) of adhesively bonded lithium disilicate ceramic. Cylindrical lithium disilicate samples were prepared and randomly assigned to four experimental groups (n = 10), based on two factors: resin cement thickness (thin ≈50 µm or thick ≈150 µm) and viscosity (high or low). A tri-layer configuration (ceramic-resin cement-ceramic) was used, with standardized ceramic discs obtained from CAD/CAM blocks. The bonding ceramic surfaces were etched with hydrofluoric acid, silanized, and a defined bonding area (≈6 mm2) was delimited using adhesive tape. The resin cement thickness was controlled by applying either one (thin) or three (thick) overlapping layers of adhesive tape. Resin cement was applied, and assemblies were seated under a 100 g static load. After light-curing, specimens were subjected to static shear bond strength testing (s-SBS) using a universal testing machine (crosshead speed: 1 mm/min; load cell: 1 kN). Failure mode was classified under stereomicroscopy, and representative samples were analysed under SEM. Additional specimens were used to confirm cement layer thickness using a profilometer. For the thick resin cement layer (≈150 µm), viscosity significantly influenced bond strength, with high-viscosity cement showing higher mean values (27.36 MPa) compared to the low-viscosity cement (19.65 MPa). In contrast, resin cement viscosity did not affect the bond strength in the thin layer condition (≈50 µm). Most specimens exhibited adhesive failure at the ceramic-cement interface. Resin cement selection based on viscosity is particularly relevant when a thick cement layer is anticipated, whereas for ideal, thin cement films, viscosity is a less consequential factor for interfacial bond strength.

Este trabalho visa verificar, por meio de análise cienciométrica, como os artigos científicos abordam a evasão em cursos de licenciatura em química do Brasil. Através da seleção de artigos no Portal de Periódicos da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, observou-se que a maioria das publicações foi realizada a partir de 2015, por instituições de ensino superior públicas da região Sul. Verificou-se também que não há produção contínua sobre o tema por parte dos autores, e 35,3% dos trabalhos não discutem a definição de evasão utilizada, dificultando a compreensão integral dos resultados. Quanto aos resultados das publicações, foi possível relacionar a evasão com fatores como a baixa identificação dos alunos com o curso, a dificuldade em conciliar trabalho e estudo, problemas com a aprendizagem, alta retenção, problemas curriculares e algumas vezes socioeconômicos. Além da identificação de altas taxas de evasão nos primeiros anos dos cursos, principalmente na forma de mobilidade acadêmica. Em contrapartida, foi possível verificar o papel positivo dos programas educacionais e política de cotas, assim como a boa integração social dos estudantes na comunidade acadêmica, como aspectos que podem mitigar o fenômeno da evasão.

: The expansion of generative artificial intelligence in education has increased the possibilities for content production, personalized learning, and pedagogical support, while also intensifying dilemmas related to authorship, information reliability, algorithmic bias, and academic integrity. In this context, teacher education requires a more complex set of professional competencies that goes beyond instrumental command of digital tools and includes curricular integration, critical curation, pedagogical mediation, and ethical responsibility. This study analyses the competencies required for teaching practice in educational settings mediated by generative artificial intelligence technologies. Methodologically, it is a qualitative bibliographic review of an exploratory-descriptive nature, developed through a structured literature search and thematic analysis. The corpus comprised academic books, peer-reviewed articles, and institutional documents directly related to the topic, examined considering both classic and recent frameworks on teacher education, digital competence, and generative AI. The analytical synthesis identified five central axes: technopedagogical integration of AI into the curriculum; curation and critical validation of generated outputs; pedagogical mediation and assessment redesign; ethics, authorship, and governance of AI use; and continuous professional development supported by institutional policies. The study concludes that the incorporation of generative AI into education does not reduce the centrality of the teacher; rather, it redefines professional responsibilities and reinforces the need for pre-service and continuing education programmes capable of articulating pedagogical, technological, and ethical dimensions within a critical and reflective perspective.