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Efeitos da fragmentação florestal sobre a predação de ninhos e comunidades de aves nidificantes da Mata Atlântica do Sudeste do Brasil
(Universidade Federal de São Carlos, 2026-04-23)
Bruno, Dáfini Letícia
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Francisco, Mercival Roberto
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https://lattes.cnpq.br/4305313620456233
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https://lattes.cnpq.br/5279431080415485
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https://orcid.org/0000-0001-7709-0620
Habitat loss and the resulting fragmentation are the primary drivers of biodiversity decline in terrestrial ecosystems. Birds respond rapidly to the effects of fragmentation, with changes in diversity, ecology, behavior, and reproduction. Nest predation is the leading cause of mortality in birds and may be intensified in fragmented habitats due to an increase in number or frequencies of generalist predators, which in the absence of top predators may increase in abundance (mesopredator release hypothesis). In this context, this thesis has as its central objective to evaluate the effects of fragmentation on the survival of forest bird nests in tropical environments, being structured in two chapters. The first chapter had as objectives to identify and compare the main nest predators in continuous and fragmented areas of the Atlantic Forest, as well as to test for the first time the mesopredator release hypothesis for a tropical forest. For this, active nests of understory birds were analyzed in one of the main continuous forest tracts of the Atlantic Forest in southeastern Brazil and in adjacent fragments. The nests were monitored in the field by camera traps, which enabled the identification of predators and the modelling of nest survival. Additionally, bird and mammal samplings were carried out to evaluate the assumption that nest predators may be more abundant in fragments due to the rarity of regulating carnivores. The results did not provide support for the tested hypothesis, since the frequencies of regulating carnivores; nest predators and nest survival rates were similar between habitats. The second chapter focused on the breeding activity hypothesis, which predicts a lower number of reproductive species and lower offspring production in fragmented environments. Using active nests as direct evidence of reproduction, nesting species richness was compared, as well as nest frequency and survival between continuous and fragmented habitats. The results did not indicate significant differences in nesting species richness between the environments, although the total frequency of nests and of certain species were higher in the fragments. Overall, the results suggest that in landscapes still relatively preserved, forest fragments may maintain relevant ecological processes and sustain reproductive bird communities. However, this apparent stability is accompanied by changes in community composition, with replacement of more sensitive species by generalist species, which may imply long-term effects on the ecological integrity of these systems.
Raw data used for determining the ionization energies of dimers of small molecular clusters
(Universidade Federal de São Carlos, 2026-04-23)
Souza, Gabriel Luiz Cruz de
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Peterson, Kirk Arnold
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Santos, José Luiz Felix
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https://lattes.cnpq.br/2821352329397835
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https://lattes.cnpq.br/3442700129094678
Modelagem matemática da reforma a vapor do etanol
(Universidade Federal de São Carlos, 2026-04-23)
Sgobi, Marcus Vinicius
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Ribeiro, Marcelo Perencin de Arruda
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https://lattes.cnpq.br/0381402687491195
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https://lattes.cnpq.br/5091119086062042
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Cruz, Antonio José Gonçalves da
The historical global dependence on fossil fuels and the growing concern regarding the worsening of the greenhouse effect demand the diversification of the energy matrix towards more sustainable alternatives. In this scenario, hydrogen stands out as a promising energy vector due to its high energy density and the absence of greenhouse gas emissions during its use. Although current hydrogen production is dominated by fossil methane steam reforming, steam reforming of ethanol emerges as a new sustainable route. To make steam reforming of ethanol viable, supported catalysts, such as Nickel and Cobalt-based bimetallics, have shown great potential in inhibiting coke formation and increasing the H2 yield. However, the high chemical complexity of the ethanol molecule generates various parallel and consecutive reactions, which hinders the elucidation of the process kinetics. Based on this context, the present work proposed a reaction pathway and, from it, developed a phenomenological kinetic model capable of describing steam reforming of ethanol for hydrogen production. Using experimental screening data previously obtained by the research group, the study implemented and compared three different algorithms for the parametric fitting of the developed model: Non-Linear Least Squares, Simulated Annealing, and the Covariance Matrix Adaptation Evolution Strategy. Before the parametric fitting, a thermodynamic analysis proved that the experimental screening tests operated far from equilibrium. The fitting results highlighted the limitations of traditional deterministic optimizations, emphasizing the robustness of the evolutive algorithm in bypassing local minima and performing uncertainty estimation through confidence intervals. Although the preliminary data were limited, they proved to be sufficient to estimate the initial kinetic parameters. These estimates were for the 4Co4Ni, 8Co,
Dinâmica populacional do psilídeo e incidência de hlb em laranja valência conduzida em diferentes porta-enxertos, espaçamentos e estratégias de controle do vetor
(Universidade Federal de São Carlos, 2026-04-23)
Cavalcanti, José Fabio Macêdo
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Cristofani-Yaly, Mariângela
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https://lattes.cnpq.br/7829946393687571
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https://orcid.org/0000-0003-0283-989X
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https://lattes.cnpq.br/6382519991127809
Huanglongbing (HLB) is the most restrictive disease in citrus farming worldwide, requiring rigorous management of its insect vector, the psyllid Diaphorina citri. This study aimed to evaluate integrated management strategies for the vector and HLB in a young Valencia orange orchard under the influence of different rootstocks (citrandarins IAC 3155, Barretos, Itajobi, Santamélia and the citrumelo Swingle), planting spacings (1.5, 2.0, 2.5 and 3.0 m) and control strategies (physical barrier with processed kaolin and chemical control with thiamethoxam via drench). The experiment was conducted at the Sylvio Moreira Citrus Center in Cordeirópolis, SP, evaluating vegetative development, sprouting dynamics, psyllid population fluctuation, HLB incidence and severity, as well as the residual effect of the insecticide. The results demonstrated that vigorous rootstocks (IAC 3155 and IAC 3073 Barretos) induced greater canopy growth, while IAC 3026 Santamélia confirmed its dwarfing characteristic. Higher planting density (1.5 m between plants in the row) accelerated coverage in the planting row and reduced the total intensity of sprouting. A strong positive correlation was found between sprouting peaks and population outbreaks of D. citri, with the Swingle and IAC 3073 Barretos rootstocks favoring greater attraction of the vector. Fortnightly spraying with kaolin acted as an effective physical and visual barrier, reducing the insect population density by up to 72% during peaks. Although the incidence of HLB remained high (>90%) throughout the area, kaolin significantly reduced disease severity and symptom progression, with optimized protection in denser plantings. In chemical control, the rootstock variety did not influence the insecticide's efficiency, which showed excellent control and residual effect for 56 days, covering two reinfestation cycles. From the 57th day onwards, the depletion of the molecule's systemic protection in the plant reduced the product's effectiveness. It is concluded that the adoption of less vigorous rootstocks, combined with denser planting and the combination of kaolin with systemic insecticides, constitutes a strategy for mitigating the HLB-psyllid complex.
Mecanismos de trincamento por fadiga em revestimentos asfálticos reforçados com geogrelhas: interação entre aderência de interface e rigidez do reforço
(Universidade Federal de São Carlos, 2026-04-23)
Santos, Karolina Maria dos
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Silva, Matheus Pena da Silva e
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https://lattes.cnpq.br/8819593174579282
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https://orcid.org/0000-0002-7009-4458
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Correia, Natália de Souza
The incorporation of geosynthetic reinforcements at the interface between asphalt layers has been widely adopted as a strategy to extend pavement service life, contributing to the reduction of permanent deformation, the improvement of fatigue resistance, and the mitigation of reflective crack propagation. In this context, numerous studies have been conducted to better understand the mechanical behavior of reinforced asphalt systems and to provide guidance for the appropriate selection and design of these materials. In particular, the literature has extensively discussed the effects of geosynthetic reinforcement inclusion on flexural performance and interface bonding conditions between asphalt layers. However, significant knowledge gaps still remain regarding the mechanisms governing the effectiveness of these reinforcements throughout the pavement service life. In particular, there is a need for a deeper understanding of the interaction between interface bonding and reinforcement stiffness, as well as the influence of these parameters on the initiation, evolution, and propagation of damage within reinforced asphalt systems. This limitation hinders the advancement of mechanistic approaches and the development of rational design methods for geogrid-reinforced asphalt pavements. In this context, the present study investigates the combined influence of interface bonding and geogrid stiffness on the fatigue performance of reinforced asphalt systems at different stages of their service life, using Digital Image Correlation (DIC) as a strain-fieldbased evaluation tool. For this purpose, an 80 m experimental section was constructed on SP-225 State Highway, comprising one unreinforced segment and three reinforced sections using polyester (G-PET), polyvinyl alcohol (G-PVA), and fiberglass (G-FV) geogrids. Specimens extracted from the field section were tested in the laboratory through Leutner-type interlayer shear tests and four-point bending fatigue tests (4PBT) under cyclic loading with DIC monitoring. The present study has advanced the understanding of the mechanisms governing the fatigue of asphalt pavements reinforced with geogrids, demonstrating that structural performance results from the interaction between interlayer bonding, reinforcement properties, and loading levels. The results highlight that the analysis of these systems under cyclic loading requires an integrated approach, combining traditional fatigue parameters, improvement factors, and image-based analysis via DIC. This integration was essential to explain results that might appear contradictory when evaluated in isolation. Four primary crack reflection mechanisms were identified. The results indicated that the effectiveness of the reinforced systems depends on the loading level, with improved performance observed at the lower load levels tested, which are more representative of actual pavement service conditions. The effectiveness of the reinforced systems was found to be strongly dependent on maintaining adequate levels of interlayer bonding, which is essential for the mobilization of the reinforcement and the transfer of stresses throughout the loading process. The study concluded that interface bonding is the key parameter governing reinforcement mobilization and the resulting performance gains, controlling the efficiency of crack mitigation systems regardless of the stiffness of the reinforcement employed. Overall, the performance of these systems cannot be attributed to a single isolated parameter, but rather to the complex interaction among geosynthetic stiffness, interface shear strength, applied stress level, and the evolution of damage mechanisms throughout the service life of the pavement structure.
As diferenças nos processos de tomada de decisão da inteligência artificial e dos seres humanos no laboratório jogo de xadrez
(Universidade Federal de São Carlos, 2026-04-23)
Andrade, Leo Pasqualini de
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Valejo, Alan Demétrius Baria
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https://lattes.cnpq.br/9546164790189830
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https://orcid.org/0000-0002-9046-9499
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Iasulaitis, Sylvia
Artificial Intelligence is an interdisciplinary field of study. Pioneers in computer science, mathematicians, and engineers envisioned the possibility of a computer simulating human thought through different computational methods, for example, artificial neural networks, inspired by biological research in the then-embryonic neuroscience. Philosophers and psychologists joined the field's research, addressing questions about the possibility of artificial intelligence thinking and having consciousness. The testing ground for artificial intelligence was chess, an ancient game with simple rules and complete information, which, in order to play it, reveals elements of human reasoning, such as selective attention, pattern recognition, abstractions, and logical reasoning. The calculations of variations in chess are performed with great accuracy by current artificial intelligence algorithms such as Stockfish and AlphaZero, but still present questions to be resolved by computer scientists in order to reach solutions conceived by human abstraction. Although the performance of chess engines has been extensively studied from a computational perspective, there is a gap in the literature regarding the systematic comparison between human and algorithmic decision-making processes in the same experimental environment. The objective of this thesis is to understand the differences, symmetries, and controversies between artificial intelligence and human intelligence in decision-making, based on a chess game laboratory. This thesis contributes to the literature by offering a novel interdisciplinary comparative analysis of human and algorithmic decision-making processes in the chess game laboratory, articulating empirical evidence, cognitive foundations, and sociotechnical interpretation. The methodological steps used were based on Bruno Latour's Actor-Network Theory, which proposes the idea of actants, where humans and non-humans join together in a network of actions. A literature review was conducted using the keywords chess, intelligence, and decision-making; an online survey was carried out with chess players on aspects of pattern recognition, abstraction, and to obtain opinions on problem situations in the context of chess. Semi-structured interviews were also conducted with computer scientists, neuroscientists, and chess masters to discuss the topic of artificial intelligence and the game of chess. The results indicated that, while chess engines predominantly compute using probabilistic calculations and tree search, humans mobilize pattern recognition from their long-term memory acquired through study and learning, as well as emotional and contextual components. It was observed that chess players with greater playing strength showed a greater ability to recognize patterns, while less experienced players resorted to mental calculations. The interviews revealed controversies among computer scientists, neuroscientists, and chess masters regarding the notion of engines simulating emotions and making abstractions. Conclusion: although chess algorithms have already surpassed humans in the game, controversies are still observed regarding these programs' understanding of game situations and their failure to consider artistic-cultural, ethical, and emotional biases—characteristics associated with human behavior and creativity. On the other hand, chess programs are tools that assist masters in their analyses before and after games and help players of all levels as a source of leisure and learning.
Detecção de objetos de trânsito da simulação para o mundo real: um estudo de adaptação de domínio não supervisionada em nível de pixel e de características
(Universidade Federal de São Carlos, 2026-04-23)
Medeiros, André Neves
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Almeida, Tiago Agostinho de
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http://lattes.cnpq.br/5368680512020633
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http://lattes.cnpq.br/6707942601520564
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Papa, João Paulo
Training object detection models for real-world applications often requires large amounts of annotated data, which can be costly and time-consuming to obtain. Synthetic datasets provide a scalable alternative, enabling automatic annotation and controlled data generation. However, models trained exclusively on synthetic data typically suffer from performance degradation when applied to real-world images due to domain shift. This dissertation investigates simulation-to-real domain adaptation for object detection, focusing on the combination of pixel-level and feature-level adaptation strategies. At the pixel level, CycleGAN is used to translate synthetic images into the visual style of real-world datasets, reducing low-level discrepancies between domains. At the feature level, the ConfMix framework is adopted as a baseline for unsupervised domain adaptation, leveraging confidence-based mixing between labeled source samples and pseudo-labeled target samples. Building upon these approaches, this work proposes TransConfMix and TransConfMix-2Stage variants, which incorporate translated synthetic images into the adaptation process, and a KL-regularized extension (ConfMix-Distill) that enforces consistency between predictions obtained from original and translated versions of the same sample. These modifications aim to improve adaptation stability and enhance model generalization under domain shift. Experiments are conducted on multiple synthetic-to-real scenarios, with DOLPHINS and SIM10K as source domains and Cityscapes and nuScenes as target domains. The results demonstrate that feature-level adaptation consistently improves over the source-only baseline across the evaluated scenarios, and that pixel-level translation can further support this process when translation quality is sufficiently high. However, the proposed hybrid extensions did not consistently surpass the original ConfMix framework, suggesting that the interaction between pixel- and feature-level adaptation is highly sensitive to domain characteristics and translation fidelity. Overall, this work provides a systematic analysis of the interaction between pixel-level and feature-level domain adaptation, showing that their combined effect in object detection is strongly dependent on translation fidelity and domain characteristics.
Comportamento estrutural de pilares de aço preenchidos com concreto de agregado reciclado cerâmico submetidos à compressão axial
(Universidade Federal de São Carlos, 2026-04-23)
Prates, Lucas Mognon Santiago
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Ferreira, Felipe Piana Vendramell
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https://lattes.cnpq.br/5933034803347448
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https://orcid.org/0000-0001-8007-789X
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Martins, Carlos Humberto
Concrete-filled steel tubular columns are an efficient structural solution for compression members, since the interaction between the steel tube and the concrete core contributes to increased strength, stiffness, and ductility. At the same time, the growing demand for more sustainable solutions in the construction sector has encouraged the use of industrial waste as a replacement for natural aggregates. In this context, the feasibility of using recycled ceramic sanitary ware aggregate as a replacement for natural sand in self-compacting concrete for steel composite columns subjected to axial compression is assessed, considering its effects on material properties, structural behavior, and strength prediction by numerical and design code models. For this purpose, the constituent materials were characterized, and two self-compacting concrete mixes were analyzed, with natural fine aggregate replacement levels ranging from 0 to 100% in the first mix and from 0 to 50% in the second, in 25% increments. Subsequently, 24 experimental axial compression tests were carried out on circular concrete-filled steel tubular columns, comprising 16 short columns and 8 columns of intermediate slenderness. In addition, a finite element numerical model was developed in ABAQUS, validated against the experimental results, and used in a parametric study with 1,442 models, varying geometric and mechanical parameters as well as the recycled aggregate replacement level. The results indicate that the incorporation of recycled aggregate reduces the workability of the mixtures, without preventing the production of self-compacting concretes with satisfactory performance. It was found that increasing the replacement level does not necessarily lead to strength loss, with strength gains observed at certain replacement levels, depending on the mix composition. In the composite columns, the structural behavior was consistent with steel-concrete composite action, with efficient filling of the tube and mobilization of confinement in the short columns, whereas, in the slender members, the response was predominantly governed by global instability. Among the replacement levels evaluated, the 25% replacement level showed the most balanced performance for structural application, as it maintained a more stable response under different conditions. The numerical modeling satisfactorily reproduced the experimental response, and the parametric study confirmed global slenderness as the variable with the greatest influence on member efficiency. It is concluded that the use of recycled sanitary ware ceramic aggregate in self-compacting concrete for filling circular concrete-filled steel tubular columns is technically feasible and structurally promising, combining satisfactory mechanical performance, reuse of industrial waste, and potential application in structural concretes.
Estratégias de acesso e mediação para repositório de informação tecnológica integrada
(Universidade Federal de São Carlos, 2026-04-24)
Erba, Ana Guelfi
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Zaniro, Dênis Leonardo
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https://lattes.cnpq.br/0800017967297543
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https://orcid.org/0000-0003-2638-9264
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Quoniam, Luc Marie
This work presents the development of an integrated repository of scientific and technological effects, with the objective of mitigating the information transfer barrier identified in an originally static knowledge base. The research, of an applied and empirical nature, was conducted to enable the conversion of a vast stock of inventive problem-solving solutions into an accessible and usable knowledge flow. Initially, a diagnostic evaluation of the spreadsheet database was carried out, identifying critical gaps in interoperability and accessibility that limited the strategic use of the data, as advocated by international guidelines for open data. The methodological path involved the logical structuring of the data, adopting a specific data type to favor the coherent representation of the content in multiple languages. Subsequently, a mediation artifact was developed—a Web system structured based on Usability principles, aiming to optimize the efficiency of human-computer interaction and information retrieval. To complement the exact relational search methodologies, the system's architecture incorporated Artificial Intelligence features through the Retrieval-Augmented Generation (RAG) technique. The implemented technological solution met the proposed objectives by establishing multiple specialized access strategies. The system enables searches from different perspectives, connecting the abstract knowledge of inventive problem-solving solutions to industrial and patent classifications, which adds strategic value to technological information. The final adherence evaluation of the artifact evidenced the alignment of the architecture with the pillars of findability, accessibility, interoperability, and reusability. It is concluded that the work provides an empirical mediation model that reiterates the relevance of the Scientific Information area in the organization and architecture of knowledge access for socioeconomic development. The solution not only contributes to broadening access to the resource but also enhances its utilization as a strategic and reusable asset.
Estruturas híbridas de poliamida 6-madeira (eucalyptus grandis) sobremoldadas por injeção
(Universidade Federal de São Carlos, 2026-04-24)
Zanchetta, Giovana Zanetini
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Canto, Leonardo Bresciani
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https://lattes.cnpq.br/7287108960864123
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https://orcid.org/0000-0002-4138-005X
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https://lattes.cnpq.br/4463643206121785
Polymer–wood hybrid (PWH) structures represent a promising alternative for sustainable structural applications. This study introduces the development of hybrid joints composed of polyamide 6 (PA6) and Eucalyptus grandis wood produced by injection overmolding, without the use of adhesives or chemical surface treatments. Two scarf joint geometries with single and double chamfers at 45° were designed and evaluated in terms of mechanical performance and interfacial adhesion mechanisms. Shear strength was determined through quasi-static mechanical tests, while the interface was characterized by scanning electron microscopy (SEM) and X‑ray microtomography (µCT). Microstructural analyses revealed a well‑defined interface, with PA6 penetrating wood vessels and forming polymer protrusions (~50 µm) that promote mechanical interlocking. Mechanical tests showed good repeatability, with hybrid joints reaching shear strength values of up to 8.1 ± 0.6 MPa, comparable to those reported in the literature for polymer–wood hybrid lap joints. Complementary digital image correlation (DIC) analyses indicated efficient mechanical coupling between the components, with a more homogeneous strain distribution for the single‑chamfer configuration, suggesting more effective stress transfer under mechanical loading.
Mapeamento de aplicações das ferramentas digitais da indústria 4.0 na cadeia de suprimentos em empresas de máquinas agrícolas
(Universidade Federal de São Carlos, 2026-04-24)
Rosa, Jorge Luiz Amaral
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Voltarelli, Murilo Aparecido
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https://lattes.cnpq.br/4889939917847330
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https://lattes.cnpq.br/5153087261053903
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https://orcid.org/0000-0003-1662-5200
The agricultural machinery sector is characterized by its importance to the Brazilian economy, generating approximately BRL 72 billion in net revenue in 2023. The supply chain is defined as the connected network from suppliers to the delivery of products and services to the customers. With the advent of technological innovations, there has been an evolution toward the concept of Supply Chain 4.0, an offshoot of Industry 4.0. There was a gap in academic research on the challenges of digital tools implementation in the agricultural machinery sector. Through exploratory research with both qualitative and quantitative approaches, the objective was to map which Industry 4.0 tools are applied in the supply chain in farm machinery companies, in the areas of Logistics, Planning and Procurement. A total of 18 employees of five companies of this sector, located in four Brazilian states - São Paulo, Minas Gerais, Parana and Rio Grande do Sul - were interviewed. Through combination of a systematic literature review and the formulation of open and closed questions, the answers were identified and analyzed to define the challenges and maturity of using digital technologies in Supply Chain area.
Flexural behavior of corroded steel beams with and without web openings: experimental, analytical, and numerical investigation
(Universidade Federal de São Carlos, 2026-04-24)
Benedito, André Vitor
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Krahl, Pablo Augusto
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https://lattes.cnpq.br/6910799550680489
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https://orcid.org/0000-0002-6172-5481
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Martins, Carlos Humberto
Corrosion is one of the most critical deterioration mechanisms affecting steel structures, since it reduces plate thickness, modifies geometric and mechanical properties, and may lead to instability, thereby compromising structural safety and load-carrying capacity. In steel beams, especially castellated beams, comprehensive studies that address the combined effects of corrosion on flexural response and local instability mechanisms remain limited, particularly regarding web-post buckling. In this context, this thesis investigates the flexural behavior of corroded steel beams with and without web openings through experimental, analytical, and numerical approaches, considering ASTM A572 Grade 50 and Grade 60 steels. The experimental program comprised tensile tests on coupons extracted from the steel profiles, three-point bending tests on solid-web and castellated beams under both corroded and uncorroded conditions, and Digital Image Correlation analyses to characterize surface imperfections, lateral displacements, and strain fields. The results showed that, in corroded solid-web beams, corrosion promoted local buckling before full cross-sectional yielding, thus changing the governing resistance mechanism. In castellated beams, corrosion significantly increased susceptibility to web-post buckling, leading to substantial reductions in load-carrying capacity of 39.05% for Grade 50 steel and 35.85% for Grade 60 steel, while the steel grade itself had no significant influence on the overall web-post buckling mode. DIC analyses further revealed localized strain concentrations around corrosion pits and earlier yielding in the tensile tie region of the web-post. Pit-depth measurements were statistically described by a log-normal distribution, with logarithmic mean and standard deviation values of 0.7951 mm and 0.3865 mm for Grade 50 steel, and 0.8918 mm and 0.4636 mm for Grade 60 steel. Based on experimental evidence, a non-empirical analytical formulation was proposed to estimate the critical load associated with web-post buckling in both corroded and uncorroded castellated beams. Compared with Steel Design Guide 31 and EN 1993-1-13:2024, the proposed model provided closer agreement with the experimental results, with lower average deviations than the code-based approaches. In parallel, a finite element model was developed in ABAQUS using a stochastic representation of corrosion based on a spatially correlated Gaussian random field. The calibration process indicated that a 15 mm mesh and a spatial correlation factor of ρf = 0.75 yielded the best agreement with the experimental load-displacement curves and successfully reproduced the corrosion-induced shift in structural behavior. Overall, the thesis advances the understanding of corrosion effects on the flexural and instability behavior of steel beams and provides analytical and numerical tools for the assessment of corroded castellated members.
Propriedade magnética de compósitos de nitreto de carbono grafítico com magnetita
(Universidade Federal de São Carlos, 2026-04-24)
Rodrigues, Adélia Victória Lázaro
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Oliveira, Adilson Jesus Aparecido de
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https://lattes.cnpq.br/4640148190073166
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https://orcid.org/0000-0003-0145-9107
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https://lattes.cnpq.br/9556361772060539
The advent of the discovery of graphene, materials based on carbon structures have been extensively investigated due to their wide range of potential applications, low production cost, and unique electronic structure. Among these materials, graphitic carbon nitride (g-C₃N₄) stands out for its diverse morphologies, such as porous nanosheets, nanotubes, nanoflakes, and nanorods, and is frequently combined with non-toxic oxides. In particular, the incorporation of magnetic materials into g-C₃N₄ opens new perspectives for even more significant applications. While graphitic carbon nitride has been widely explored for hydrogen generation through processes such as water electrolysis and the photodegradation of environmental pollutants, magnetite has been extensively studied for its magnetic properties and its potential applications in areas such as energy storage and water treatment. The aim of this dissertation is to investigate the structural and magnetic properties of the (1–x) g-C₃N₄/(x) Fe₃O₄ composite, with x = 0.01, 0.05, 0.10, 0.20, 0.30, and 0.40. The focus is the comparison between powder and pelletized samples, analyzing the magnetic behavior of the material under different pelletizing pressures. Our results show that the application of pressure to the samples leads to significant changes in remanent magnetization, saturation magnetization, and coercive field, indicating that pressure-induced structural modifications directly affect the magnetic behavior of the composites.
Personalizing mental health support: a retrieval-based llm approach to conversational agent development
(Universidade Federal de São Carlos, 2026-04-24)
Passador, Rafael Vinicius Polato
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Caseli, Helena de Medeiros
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https://lattes.cnpq.br/6608582057810385
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https://lattes.cnpq.br/8275474576606344
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Papa, João Paulo
Mental health disorders constitute a major global challenge, requiring support solutions that are both accessible and scalable. Conversational agents have emerged as promising tools in this context, but purely generative large language model (LLM) systems remain susceptible to unsupported outputs, weak grounding, and limited adaptation to user-specific context. This work investigates whether combining supervised domain adaptation, guideline-grounded retrieval, and persona-based conditioning improves the quality of emotional-support responses. Three system variants built on the same fine-tuned Llama-3 backbone are compared: a Baseline model controlled through layered prompting, a Hybrid Retrieval-Augmented Generation (RAG) variant grounded in authoritative WHO and NICE mental health guidelines through hybrid retrieval, and a Persona-Based RAG variant that further incorporates persona signs into both retrieval and prompt construction. All variants are protected by a pre-LLM crisis guardrail that short-circuits high-risk inputs and returns a predefined safe response. Evaluation was conducted in a single-turn setting using inputs from mental health datasets associated with multiple persona profiles, and outputs were assessed through both human evaluation and an LLM-as-a-judge protocol under a shared rubric covering empathy, topic adequacy, and personalization. Results from both evaluation sources converge in identifying the Persona-Based RAG variant as the best overall configuration, with the clearest gains in empathy and personalization, while the RAG-only variant remained especially competitive in topic adequacy. These findings indicate that combining grounded retrieval with explicit persona conditioning is a promising strategy for the development of more contextually appropriate and supportive conversational agents for mental health.
Pseudociência no ensino: análise das percepções e posturas de professores da área de ciências da natureza
(Universidade Federal de São Carlos, 2026-04-24)
Jesus, Atair José Bernardino de
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Gebara, Maria José Fontana
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https://lattes.cnpq.br/6585493065968961
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https://orcid.org/0000-0002-9399-3683
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https://lattes.cnpq.br/3604597187568726
Pseudoscience consists of a body of ideas and practices characterized by difficult demarcation; it presents itself through explanations with a scientific appearance, yet fails to meet the fundamental criteria that characterize the production of scientific knowledge, such as testability, falsifiability, critical analysis, and peer validation. Beyond the difficulties regarding its definition, pseudoscience exhibits recurrent characteristics identified in the literature, such as a tendency to present itself as an alternative or superior form of knowledge, exploiting the limitations, uncertainties, and errors of science itself to challenge its credibility. These theories frequently gain traction by offering simplified and emotionally appealing explanations for complex phenomena, in contrast to science, which is characterized by the constant revision of hypotheses, critical analysis, and falsifiability. Adherence to pseudoscientific beliefs is also linked to cognitive predispositions that favor pattern-seeking, simple explanations, and a sense of control in the face of uncertainty. In this context, pseudoscience produces impacts that transcend the epistemological realm, affecting decisions related to health, social life, and education, particularly within a landscape marked by the widespread circulation of information and the dissemination of misinformation in digital environments. Although not a recent phenomenon, its presence has intensified across different social contexts, especially through conspiracy theories and anti-scientific discourses in digital media. This scenario became particularly evident during the COVID-19 pandemic, when pseudoscientific explanations and false information vied for space with established scientific knowledge on topics related to public health, vaccination, and disease prevention. Given this context, schools assume a significant role in promoting scientific literacy and critical thinking, leaving teachers to mediate between scientific knowledge and the discourses circulating in society. This research investigates the perception of K-12 Natural Sciences teachers regarding pseudoscience and its presence in education. It stems from the understanding that how educators comprehend, interpret, and position themselves toward pseudoscience can directly influence both classroom pedagogical practices and students' scientific development. The investigation was guided by the following research questions: How do K-12 Natural Sciences teachers perceive pseudoscience in education? What teacher positioning profiles regarding pseudoscience can be identified based on these teachers' perceptions? As a general objective, this study sought to analyze how K-12 Natural Sciences teachers perceive pseudoscience in education. Specifically, it aimed to identify and characterize teacher positioning profiles regarding pseudoscience based on the stances assumed by teachers within the context of Natural Sciences education; analyze the conceptions of pseudoscience held by these educators; and investigate how they self-identify in relation to pseudoscience. For data collection, the Investigative Questionnaire on the Perception of Pseudoscience in Natural Sciences Education (QIPPECN) was developed by the author in collaboration with the Research Group on Science Teaching and Communication (GPEDiC). The instrument was administered in a virtual environment via the Survio platform, with the participation of 178 K-12 teachers working across different educational stages, from Early Childhood Education to High School, spanning various regions of the country. Although it engaged participants from different cities and regions, the study does not claim statistical representativeness of the national teacher population. The research adopted a mixed-methods approach using elements of Content Analysis (CA), descriptive statistics, and inferential statistics, with emphasis on Exploratory Factor Analysis (EFA) and Spearman's correlation coefficient (ρ). The results indicate that most participants recognize pseudoscience as a domain distinct from science and reaffirm the centrality of scientific knowledge in Natural Sciences education. However, the data also reveal the coexistence of diverse teacher positions regarding the phenomenon, including perspectives aimed at critically confronting pseudoscience, neutral stances, and attitudes of omission, which may be associated with professional insecurity and the absence of explicit curricular guidelines for addressing the topic. Furthermore, conceptual gaps were identified among a portion of the respondents, who understand pseudoscience as a preliminary stage or a developing science, highlighting weaknesses in epistemological training.
Avaliação de estratégias empregando NADES para o preparo de amostras de peixes visando à determinação de macroelementos por ICP-OES
(Universidade Federal de São Carlos, 2026-04-27)
Duarte, Jeysse Fatima
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Nogueira, Ana Rita de Araújo
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https://lattes.cnpq.br/7034773971317045
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https://lattes.cnpq.br/0553770466040410
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Silva, Ana Beatriz Santos da
EVALUATION OF STRATEGIES EMPLOYING NADES FOR THE PREPARATION OF FISH SAMPLES AIMING AT THE DETERMINATION OF MACROELEMENTS BY ICP-OES. The sample preparation step is crucial for obtaining consistent results in chemical analyses, since contamination and loss of some analytes can occur in this process. Conventional digestion methods employ strong acids, such as nitric acid, which promote matrix decomposition but are dangerous and generate significant waste. As an alternative to reduce these impacts, this work evaluated the use of green solvents, such as eutectics (DES/NADES). Deep eutectic solvents (DES) are formed by a hydrogen bond acceptor (HBA) and a hydrogen bond donor (HBD), resulting in a eutectic system with a lower melting point. Natural deep eutectic solvents (NADES) are composed of natural compounds, namely amino acids, organic acids, and sugars, and offer advantages such as lower toxicity, biodegradability, sustainability, and relatively simple preparation. The levels of Ca, K, Mg, Na, and P extracted from fish tissues were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), which exhibits good sensitivity and multi-element capability. Different organic acids (formic, malonic, and oxalic acids) were evaluated as hydrogen bond donors, and choline chloride was used as a hydrogen bond acceptor in a 1:1 ratio. Extraction was performed on fish tissue reference material (MR-agro E3002A) using a thermostatic bath and ultrasound, and the recovery (%) and relative standard deviation (RSD%) of the evaluated analytes were compared. Extractions performed in a thermostatic bath showed recoveries between 68% and 100% compared to the values described in the reference material and a relative standard deviation (RSD) < 18%. Subsequently, the influence of adding water to the composition of the eutectic solvents (1 to 4 mol H2O) was evaluated. Recoveries and relative standard deviations indicated that the NADES composed of choline chloride: formic acid: water (1:1:4) showed the best performance. An experimental design (Doehlert) was carried out to simultaneously optimize the extraction responses of the five analytes, considering extraction time and eutectic solvent volume, and to evaluate the multiple response (MR). The results obtained indicated that the optimized condition, with recoveries of 77–92% and RSD (%) of 0.1–18%, was: 90 min of extraction and 4 mL of NADES. Validation demonstrated adequate reliability of the developed method, and the evaluation using the AGREEprep metric resulted in a score of 0.48. Replacing traditional acid digestion with deep eutectic solvents, especially NADES, as a sample preparation step for fish tissue introduces a more sustainable, less toxic approach with lower waste generation, while maintaining nutrient extraction efficiency, reducing laboratory risks, simplifying preparation, and strengthening alignment with green chemistry practices.
Experiências de adoecimento de indígenas universitários: em um município do interior de São Paulo
(Universidade Federal de São Carlos, 2026-04-27)
Mutti, Julio Cesar
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Nordi, Aline Barreto de Almeida
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http://lattes.cnpq.br/9965335072268661
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Luna, Willian Fernandes
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http://lattes.cnpq.br/1860768963636452
According to the latest census, the Indigenous population in Brazil is close to 1.7 million people, with a significant proportion living in urban areas. This displacement is related to historical processes such as the invasion of territories, violence in contact with non-Indigenous society, difficulties in income generation, and access to higher education. The Federal University of São Carlos (UFSCar), which has implemented Affirmative Action Policies for eighteen years, has become an important destination for Indigenous students from different regions of the country. This study aimed to understand the therapeutic itineraries and experiences of illness among Indigenous university students at UFSCar, São Carlos campus, in the urban context. This was a qualitative, exploratory study, using field diaries, questionnaires, and individual interviews as data construction instruments. Thirteen Indigenous participants took part, representing the Atikum, Bakairi, Baniwa, Baré, Pankará, Terena, Truká, Tukano, Wassu-Cocal, and Xavante peoples, from diverse regions, age groups, genders, sexual orientations, and university programs. The thematic content analysis revealed five categories: experiences at the university with unfollings on health; forms of violence generating suffering among Indigenous university students; experiences of illness among Indigenous university students; models of care in health–illness processes; and experiences with health services. The results show that illness goes beyond the biomedical field, encompassing physical, spiritual, territorial, emotional, and collective dimensions, and that moving to the university entails symbolic and ontological ruptures, intensified by institutional and academic racism. It was also observed that therapeutic itineraries are shaped by intercultural barriers within health services, leading students to mobilize self-care practices grounded in ancestral knowledge, often combined with other models of care. It is concluded that ensuring these students’ right to health requires institutional changes guided by interculturality, the valuing of Indigenous knowledge, and the articulation between universities and the health system, pointing to the need for integrated public policies that are sensitive to Indigenous specificities.
Formação de professores da Educação de Jovens e Adultos na Rede de Aprendizagem e Desenvolvimento da Docência da UFSCar
(Universidade Federal de São Carlos, 2026-04-27)
Abreu, Cremilda Peres Cangussu de
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Anunciato, Rosa Maria Moraes
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https://lattes.cnpq.br/3064136997342775
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https://orcid.org/0000-0003-1478-411X
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https://lattes.cnpq.br/9764800072819609
This research, centered on teacher education, aimed to analyze elements of Teacher Learning and Professional Development experienced by undergraduate students in Pedagogy and by novice and experienced teachers from Youth and Adult Education (EJA) during their participation in an extension activity carried out within the Teaching Learning and Development Network (ReAD), in the Moodle environment of UFSCar. The investigation adopted a qualitative approach with collaborative aspects. For data collection, questionnaires, interviews, logbooks, and written narratives produced in the context of an online extension activity offered by the Federal University of São Carlos (UFSCar) were used, totaling 120 hours between January and July 2024. The educational activity had a dual purpose, both research and teacher education, and involved undergraduate Pedagogy students from UFSCar and from the Federal University of the South and Southeast of Pará (Unifesspa), in addition to Youth and Adult Education (EJA) teachers from municipal and state public schools in the south and southeast of the state. The data were processed and categorized based on Bardin’s Content Analysis technique. The results were organized into categories and subcategories which allowed analyzing: a) the participants’ perspectives on teaching; b) the manifestations of the demands, challenges, and possibilities of EJA in the context of ReAD/UFSCar; c) reflections on the contributions of the experiences to practical knowledge in EJA within the scope of ReAD/UFSCar; and d) the potentialities and limitations of the online extension activities from the perspective of Pedagogy undergraduate students and EJA teachers, based on the supporting literature and the objectives of the study. The analyses show that the online extension activities in ReAD contributed significantly to the appreciation of intergenerational dialogue among students and novice and experienced EJA teachers. This dialogue, built around theoretical and methodological approaches and the sharing of individual and collective experiences, fostered new learning experiences within the teaching context. As an educational and collaborative space, ReAD showed strong potential for the education of undergraduate students and practicing teachers by promoting and strengthening teacher agency. Furthermore, participants highlighted that the online educational process stimulated reflection on teaching and the investigation of pedagogical practices, broadening theoretical and practical knowledge and promoting new learning experiences, as well as personal and professional development for teachers. The research also indicated that demands in the field of EJA, such as the adaptation of curriculum proposals, the inclusion of EJA in academic debates, and the revision of pedagogical practices, are pathways for new investigations, for strengthening academic production, and for expanding content in future teacher education programs, in accordance with the specificities of Youth and Adult Education. We concluded that, despite the difficulties related to the scarcity of technological resources among participating teachers and limited access to reliable internet, the participants acknowledged the relevance and broad accessibility of the online extension activities, which expanded opportunities for teacher education in regions geographically far from the country’s major educational hubs.
A chamada à formação do cidadão: governamentalidade no Ensino de Ciências
(Universidade Federal de São Carlos, 2026-04-27)
Herculano, Bruna Gabriela Nico Pereira
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Souza, Carolina Rodrigues de
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http://lattes.cnpq.br/8152101475247049
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https://orcid.org/0000-0002-7826-1011
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http://lattes.cnpq.br/8671917257717460
This thesis investigates how the Teaching of Sciences was constituted as a field of dispute around the formation of the citizen. Inspired by the philosophy of difference, mainly Michel Foucault’s genealogical perspective, in dialogue with Gilles Deleuze, it analyzes statements present in official documents and productions from the field itself, articulating them with events in the history of Brazilian education. From this movement, through a genealogical gesture, it analyzes the historical and discursive conditions that made possible the articulation between Teaching of Sciences and the formation of the citizen in Brazil, questioning the ways in which this relationship participates in the production and modulation of specific subjectivities. It starts from the hypothesis that Teaching of Sciences operates in the service of a governmental rationality whose sign is citizenship, which, in turn, operates in the subjectivation of bodies, calling on them to constitute themselves as citizen subjects. It observes that the Teaching of Science has sought to format this subject through different adjectives (critical citizen, technical, responsible, among others), while qualifying citizenship itself according to cognitive criteria and competencies informed by scientific knowledge. Public participation is progressively translated as the ability to interpret data, evaluate evidence, and make rational decisions, leading citizenship to operate as a regulatory axis of the educational experience. Instead of proposing a new definition of citizenship, the thesis shifts the debate to problematize what citizenship does within the field, a critique that should not be confused with discourses of institutional delegitimization of the school; rather, it seeks to make explicit the mechanisms that operate in the countryside, in order to sustain the school as a public territory of dispute and invention. Finally, it proposes a theoretical, non prescriptive experimentation which questions the possibility of a Teaching of Sciences as re-existence: approximated to the Foucaultian notion of counter-conduct, it is a reading mode that examines the internal variations of the rationality of citizenship in the field. By evidencing displacements, fissures and rearrangements that occur within these rationalities, the thesis expands the possibilities of understanding the Teaching of Sciences, indicating that, even within the school apparatus, cracks emerge through which one can re-exist in the school.
Características de estabilidade e shelf life de cosméticos nanoestruturados: uma revisão
(Universidade Federal de São Carlos, 2026-04-28)
Farina, Rafael
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Pereira Filho, Edenir Rodrigues
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https://lattes.cnpq.br/3394181280355442
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https://orcid.org/0000-0003-0608-0278
Nanotechnology applied to cosmetology represents a significant breakthrough in the delivery of active ingredients, seeking to overcome the permeation limitations of conventional formulations. This study aimed to critically analyze, through a qualitative literature review (Web of Science, Google Scholar, and SciELO), the influence of nanostructured systems on the stability and shelf life of cosmetic products. Unlike a generalist approach, the results evidenced that nanostructuring does not inherently provide absolute stability, as these are thermodynamically unstable systems. It was analytically established that solid matrices—such as Solid Lipid Nanoparticles (SLNs) and polymeric nanocapsules—offer superior structural protection against degradation and premature leakage of the active ingredient when compared to fluid systems, such as liposomes and nanoemulsions. In the context of quality control, it was found that the application of stability studies governed by ANVISA guidelines is indispensable, yet insufficient to certify the integrity of nanosystems. Aligning with the FDA's regulatory requirements for nanomaterials, shelf life validation mandatorily requires instrumental monitoring through Dynamic Light Scattering (DLS) and Zeta Potential. In conclusion, although nanotechnology optimizes cosmetic performance, its wide application still faces critical challenges and limitations, notably the gaps in nanotoxicology regarding involuntary systemic absorption, the high cost of characterization, and the severe mechanical obstacles involved in industrial scale-up.