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Síntese e funcionalização de compostos heterocíclicos visando a descoberta de fármacos antivirais
(Universidade Federal de São Carlos, 2025-04-25) Santos, Jhonathan Renner Nunes dos; Corrêa, Arlene Gonçalves; https://lattes.cnpq.br/7425467156776144; https://orcid.org/0000-0003-4247-2228; https://lattes.cnpq.br/3969751736153847; https://orcid.org/0000-0002-4193-2942
The humanity has faced numerous viral epidemics, significantly impacting daily life. Notable examples include infections caused by dengue and Zika virus, as well as the COVID-19 pandemic caused by the SARS-CoV-2. In this respect, the scientific community mobilized a task force to develop vaccines and new therapies. Drug repurposing also played a crucial role during this period, as seen with remdesivir, a C-glycoside originally developed to combat the Ebola virus, that became one of the first drugs approved for emergency use against SARS-CoV-2. Despite having a well-established synthetic route, remdesivir production still posed challenges, prompting various research groups to optimize steps with low yields or harsh reaction conditions. In this context, the objective of this thesis was to synthesize C-glycoside analogs using more sustainable methods, such as C-H functionalization of N-heterocycles via photochemical processes and multicomponent reactions. Once these compounds were synthesized, their biological activity was evaluated against the proteases Mpro and PLpro of SARS-CoV-2 and NS2B-NS3Pro of the Zika virus. Concerning the C-H functionalization of N-heterocycles, 14 compounds were synthesized, with yields ranging from 10% to 81%. The developed protocol demonstrated to be regioselective, enabling the formation of a C-C bond at the C-7 position of pyrrolo[2,1-f][1,2,4]triazine. Then, 38 compounds were obtained, including derivatives of dihydropyrimidine-2(1H)-ones/thiones (DHPMs), coumarins, DHPM-coumarin hybrids, and coumarin dimers. These compounds have demonstrated potential in inhibiting the viral activity of SARS-CoV-2 and the Zika virus. For SARS-CoV-2, seven compounds showed promising activity against the Mpro enzyme, with IC50 values ranging from 4.8 to 87 µM. Six compounds exhibited effectiveness against PLpro, with IC50 values between 21 and 81 µM. Regarding the Zika virus NS2B-NS3Pro, seven compounds displayed activity, with IC50 values ranging from 0.4 to 7.1 µM. In summary, this study successfully identified potential enzymatic inhibitors for SARS-CoV-2 and Zika virus proteases using more sustainable approaches, including photochemistry and multicomponent reactions. Further studies may be conducted to enhance the efficacy of these compounds.
Experimental and numerical assessment of global and local stability of steel-UHPC composite alveolar beams under hogging bending
(Universidade Federal de São Carlos, 2025-04-25) Oliveira, Vinicius Moura de; Rossi, Alexandre; https://lattes.cnpq.br/3946998323160911; https://orcid.org/0000-0001-9590-1554; Martins, Carlos Humberto; https://lattes.cnpq.br/1665294496138141; https://orcid.org/0000-0001-7342-5665; https://lattes.cnpq.br/4943231902952522; https://orcid.org/0000-0002-9841-0475
Continuous steel-concrete composite beams provide bending moment redistribution, slight deflection, the capability to cover longer spans, and cost-effectiveness. Employing steel alveolar I-sections, High-Strength Steel (HSS), and Ultra-High-Performance Concrete (UHPC) slabs in these composite beams can significantly dematerialize the structure. To the best of authors' knowledge, no studies have addressed the adoption of high-performance materials for composite alveolar beams. At the same time, composite alveolar beams under hogging bending with shear forces can reach local and global instability or the interaction between the modes, such as Lateral-Distortional Buckling (LDB) and Web-Post Buckling (WPB), requiring further investigation. The present study aimed to investigate the occurrence of LDB and WPB in composite alveolar beams, considering HSS I-sections and UHPC. For these objectives, both experimental and numerical analyses were conducted. Three-point bending tests were carried out in steel-UHPC composite castellated beams with I-sections of microalloyed steels with Niobium addition. The experimental results were used to validate the numerical model, and numerical parametric studies were also conducted. The specimens reached failure by WPB coupled with the Vierendeel mechanism (VM). This way, the length of the web openings' hexagon horizontal edge (tee length) influenced the bearing capacity of the castellated beam, in which the specimen with a higher tee length had a lower ultimate load, which was also observed in the numerical parametric study. In addition, the numerical models with the shortest web-post width were more critical for the WPB occurrence. The parametric study models also reached failure by LDB coupled with WPB, showing an elevated influence of the I-section steel yield strength, and composite castellated beams with UHPC slabs showed higher initial bending stiffness and ultimate loads than those with Normal Concrete (NC) slabs. Given this, some possibilities to dematerialize conventional composite beams under hogging bending by using HSS castellated I-sections and slabs of UHPC were verified. The dematerialization rate considered in the analysis regards the ratio between the volume of material consumption of the conventional element and the dematerialized element. Even when instability modes occur in the I-section, an I-section dematerialization rate of up to 55% can be reached using HSS castellated I-sections. In addition, only adopting the castellated I-sections, without changing the steel yield strength, can present an I-section dematerialization rate of up to 17.9%. The slab concrete can reach the dematerialization rate of 33.3% by utilizing UHPC instead of NC. Finally, the updates in ABNT NBR 8800:2024 presented a more accurate LDB resistance prediction than the previous version (ABNT NBR 8800:2008). In most cases, European codes (EC4/EC3) provided conservative LDB and WPB resistance prediction.
Entropia de transferência para cadeias estocásticas com memória de alcance variável
(Universidade Federal de São Carlos, 2025-04-25) Santana, José Olívio da Silva; Ferreira, Ricardo Felipe; https://lattes.cnpq.br/2355076087945221; https://lattes.cnpq.br/7256020961352532
Transfer entropy is a measure of causality between two time series, quantifying the information that one process provides about the future of another. In this thesis, we consider the problem of estimating the transfer entropy rate between two discrete stochastic processes using the plug-in estimator. When the joint process is a stationary, absolutely regular chain with variable-length memory and whose the dynamics is governed by a 𝑔-function that is not necessarily continuous but is perfectly simulatable, we derive bounds for the probability of concentration of the empirical transfer entropy around its mean and its rate. Next, we establish the convergence of this estimator to a normal distribution, thus providing a Central Limit Theorem for this functional. In this case, we restrict our analysis to processes compatible with continuous 𝑔-functions.
Otimização da produção de Goma Xantana: cultivo em biorreator, modelagem e análise de operabilidade
(Universidade Federal de São Carlos, 2025-04-25) Oliveira, Davi Benedito; Silva, Adilson José da; https://lattes.cnpq.br/3447469350644179; https://orcid.org/0000-0002-3362-6208; Horta, Antonio Carlos Luperni; https://lattes.cnpq.br/5923938048634505; https://orcid.org/0000-0002-3042-0351; https://lattes.cnpq.br/0403958118014255; https://orcid.org/0000-0003-1395-9272
Xanthomonas, a genus of phytopathogenic bacteria, is renowned for producing xanthan gum, a highly viscous biopolymer with diverse industrial applications. Our research group recently engineered a strain that boosts xanthan gum productivity by 50% compared to the wild type. High-viscosity broths often hinder mass transfer and oxygen supply in aerobic cultures. While previous studies have tackled these challenges through advanced aeration and mixing strategies, our approach takes a different path. The hypothesis proposes that the implementation of a controlled continuous cultivation system designed to keep viscosity within an optimal range would ensure unobstructed medium mixing and maintain adequate oxygen transfer. To realize this strategy, a kinetic model was developed capturing biomass growth, product formation, and substrate and oxygen consumption. Existing models from the literature were adapted to fit our experimental data from bench-scale bioreactors. The final model is supported by a neural network trained on our viscosity measurements to predict how viscosity evolves as xanthan gum accumulates. This combined framework supports simulations of batch, fed-batch, and continuous processes, offering versatile tools for process design and optimization. The system was validated with batch cultures in 1.5 L and 6 L bioreactors, and an operability study was conducted under continuous conditions. These experiments identified process parameters that sustain optimal viscosity and maximize oxygen transfer. Ultimately, the approach delivered a 220% productivity increase over standard batch processes, far exceeding initial expectations.
Ensino de precisão: um sistema para ensino de habilidades e treinamento para profissionais que atuam com pessoas autistas
(Universidade Federal de São Carlos, 2025-04-25) Moraes, Priscilla Terumi; Carmo, João dos Santos; https://lattes.cnpq.br/1263046410329694; https://lattes.cnpq.br/9518547135700384
This thesis investigates the effectiveness of Precision Teaching (PT) in training professionals working with autistic individuals. The thesis comprises four articles exploring various aspects of PT, including its implementation, efficacy in interventions with autistic individuals, the impact of graph standardization on clinical decision-making, and an online procedure for teaching the Standard Celeration Chart (SCC). Chapter 1 is introductory and explains the thesis' objectives. Chapter 2 provides a comprehensive introduction to PT, detailing its core components and offering a practical implementation guide. Chapter 3 presents a systematic literature review analyzing PT's efficacy in interventions with autistic individuals. The review included 11 studies with diverse methodological characteristics (designs, populations, skills taught). Results showed strong evidence of PT's effectiveness in academic skills (primarily mathematics and reading), along with indications of maintenance, resistance, stability, application, and generalization. The review also highlights the need for future studies with enhanced methodological rigor. Chapter 4 investigates how behavior analysts use graphs for decision-making, assessing the influence of graph standardization. In this study, 19 analysts examined 5 graphs (3 line graphs, 2 SCCs) with identical data but different scales and representations. Chapter 5 presents a study evaluating an online teaching procedure for the SCC. Four behavior analytic therapists participated, training on 18 skills using videos and online meetings. Results indicated the procedure's effectiveness in increasing correct responses and decreasing errors, with 93.4% inter-observer agreement. Results demonstrate that graph standardization improves agreement among analysts regarding instructional decisions. Finally, Chapter 6 discusses the findings, their implications for practice and research, and suggests future directions. In summary, this dissertation contributes to understanding and applying PT in interventions with autistic individuals.
AmarElo: passagens Intermidiáticas entre o álbum fonográfico e o documentário musical
(Universidade Federal de São Carlos, 2025-04-25) Vieira, Matheus José; Paiva, Samuel José Holanda de; https://lattes.cnpq.br/7222933274927263; https://lattes.cnpq.br/4031343458755251
This research project focuses on the musical documentary Emicida: AmarElo – É Tudo Pra Ontem (2019), directed by Fred Ouro Preto and produced by Laboratório Fantasma in coproduction with Netflix. The film analysis is based on the concept of “intermedial passages” (NAGIB, 2018) among the various media products that make up the AmarElo project—album, music videos, live performance, and podcast—to investigate how these relationships construct its narrative. The research is situated within the history of “Brazilian Black Cinema” (CARVALHO, 2022) and seeks to answer: how can the production of this film be understood from the perspective of contemporary Brazilian Black Cinema? The hypothesis suggests that intermedial passages expand the possibilities for inserting Emicida’s discourse and that of Laboratório Fantasma, articulating culture and politics as means of confronting structural racism (ALMEIDA, 2019) in Brazil. The results indicate that intermediality in the documentary is not merely a market strategy but functions as a central element in the construction of a political project. The film reaffirms the memory of Black resistance in Brazil and establishes connections with the Afro-diaspora, revisiting episodes such as the Unified Black Movement’s demonstration at the Theatro Municipal in 1978. To deepen this analysis, the research examines the intermedial passages in the songs AmarElo, Quem Tem um Amigo Tem Tudo, and Pantera Negra.
O “DNApraQ?” como espaço de aprendizado mútuo: relato de experiência pessoal em divulgação científica
(Universidade Federal de São Carlos, 2025-04-25) Massone, Luís Mário Nicoletti; Medeiros, Ane Hackbart de; https://lattes.cnpq.br/6315858319851377; https://orcid.org/0000-0003-3985-3193; https://lattes.cnpq.br/4623230409017740
Personal experience is one of the most enriching forms of learning, allowing the interaction with different contexts and people. This work explores my experience as a member of the science communication group “DNA pra Q?”, an initiative created at the Federal University of São Carlos, Araras campus. The report details the activities carried out by the group, such as the production of educational content for social media, the organization of in-person events, and the conduction of practical workshops, highlighting the impact of these actions in combating scientific misinformation, especially in a scenario marked by the times during and post-COVID-19 pandemic. Based on these experiences, I describe the knowledge acquired both academically and personally. My participation in the project provided the development of essential skills such as leadership, communication, and teamwork, as well as broadening my understanding of the role of science in society. Direct contact with a heterogeneous group and with the public reinforced the importance of empathy and mutual learning in this process, especially in the context of teacher education. Furthermore, it highlights how initiatives similar to “DNA pra Q?” promote a more open dialogue between science and society since, through active engagement with different audiences, these actions help to demystify incorrect concepts, combat scientific misinformation, and strengthen critical thinking. It is concluded that projects of this nature not only assist in training future educators but also represent an opportunity to establish transformative connections for a more accessible and collaborative science.
Mecanismos de coexistência em espécies com ciclo de vida complexo: um estudo sobre libélulas neotropicais
(Universidade Federal de São Carlos, 2025-04-25) Pestana, Gabrielle Cristina; Saito, Victor Satoru; https://lattes.cnpq.br/3312862423985585; https://lattes.cnpq.br/6363707133266300
Community ecology aims to understand the maintenance of biodiversity through the mechanisms that enable species to coexist in local communities. The Modern Coexistence Theory (MCT), synthesized by Chesson (2000), is one of the most rigorous frameworks for understanding how competing species persist in the same environment over time. According to this theory, two types of interspecific differences determine stable coexistence: fitness differences and niche differences. Fitness differences are related to variation in species’ competitive and reproductive abilities and, when too large, may lead to the competitive exclusion of lower-fitness species over time. In contrast, mechanisms that increase niche differences (stabilizing mechanisms) promote stronger intraspecific than interspecific competition, reducing resource overlap among species and thus favoring coexistence. For example, reproductive interactions such as territoriality can intensify intraspecific competition, acting as a stabilizing mechanism. Over recent decades, MCT has been widely discussed and applied in both theoretical and empirical studies to investigate how these mechanisms operate across different ecological scenarios. In this context, insects of the order Odonata are excellent models for understanding coexistence mechanisms in species with complex life cycles, as they have an aquatic larval stage and a winged adult stage characterized by diverse reproductive behaviors. Thus, the present thesis aimed to investigate the mechanisms related to intra- and interspecific interactions across different life stages of Neotropical dragonflies. It is structured into three chapters: Chapter I presents an introduction to the main concepts and mechanisms of MCT, along with a scientometric analysis of empirical and theoretical studies published since Chesson (2000), including data on the number of publications by country, taxonomic groups, studied ecosystems, and methodologies employed; Chapter II analyzes the influence of biotic and abiotic factors on the variation in wing spot size (a trait associated with territoriality and male-male sexual competition) in Hetaerina rosea Selys, 1853, both within and among populations. For this purpose, data on intraspecific abundance, total abundance, vegetation cover, and site location were collected from 46 sites in the Central-West region of Brazil. Finally, Chapter III investigates how the effects of intra- and interspecific interactions vary across the life cycle of tropical dragonfly species. The hypothesis tested was that larval-stage competition is predominantly neutral, that is, independent of species identity and driven by total individual density, whereas adult-stage interactions are more intense at the intraspecific level due to reproductive behaviors. To test this, laboratory experiments were conducted using larvae of Acanthagrion (Zygoptera, Coenagrionidae) and Erythrodiplax (Anisoptera, Libellulidae), varying both total abundance and species dominance. Additionally, field observations were carried out to analyze co-occurrence and the frequency of interactions among adults of different Zygoptera and Anisoptera species. In this way, the findings of this dissertation contribute to a deeper understanding of the ecological mechanisms that sustain biodiversity by integrating MCT with empirical studies on Odonata.
Impacto da morfologia urbana nas condições térmicas internas e externas de habitações de interesse social: acoplamento entre ENVI-met e EnergyPlus
(Universidade Federal de São Carlos, 2025-04-25) Apolinário, Bruna de Souza; Masiero, Érico; https://lattes.cnpq.br/2691827106518167; https://orcid.org/0000-0001-8665-335X; https://lattes.cnpq.br/4617953999200789; https://orcid.org/0000-0001-8472-453X
Amid global warming, the increasing occurrence of heat waves, and the urban heat island effect, exploring solutions to mitigate human thermal stress and energy demand for cooling becomes essential. In this context, urban planning that considers morphology indices aligned with the climate contributes to improving both external and internal thermal conditions of housing. Based on these issues, this study aims to analyze the external and internal thermal conditions of social housing units in relation to verticality and built typologies, both during and outside a heat wave. To achieve this, scenarios were developed with three housing typologies: single-story houses, H-shaped towers, and courtyard buildings. Multifamily housing was analyzed at two heights: 14 and 29 meters. The methodology was based on the collection of microclimatic data and computational simulations. The scenarios were simulated using the ENVI-met software, with the collected data used as input. The microclimatic data from these simulations were subsequently coupled to EnergyPlus using the chaining method and the BCVTB software. The results highlighted the high levels of thermal stress to which social housing residents are exposed during heat waves, which can cause heat cramps, exhaustion, and heatstroke, negatively affecting health and well-being. Additionally, it was found that scenarios with courtyard buildings performed best externally, being the only ones to provide areas without extreme thermal stress. However, internally, they generated the highest levels of thermal stress and energy demand for cooling, with a 29.22% increase. On the other hand, H-shaped towers, despite presenting less favorable external thermal conditions compared to courtyard buildings, achieved the best internal results. These scenarios were the only ones without internal thermal stress levels classified as "at risk" and reduced cooling energy demand by 20.97% compared to single-story houses. Regarding building height, the reduction proved advantageous during the heat wave but unfavorable outside this period. These results highlight the impact of housing typologies and building height on thermal stress levels and energy demand for cooling. However, they indicate that while an urban configuration may improve external thermal conditions, it may worsen internal conditions. Therefore, it is essential to deepen studies on the impact of urban morphology on the indoor thermal environment of housing to support urban planning that minimizes both energy consumption and external and internal thermal stress.
As contradições presentes no currículo e nos projetos políticos pedagógicos das escolas do campo de Limeira/SP: uma análise a partir da Pedagogia histórico-crítica
(Universidade Federal de São Carlos, 2025-04-25) Jurgensen, Karina Yara; Santos, Maria Cristina dos; https://lattes.cnpq.br/1095065753077001; https://lattes.cnpq.br/5218454576679092
This research investigates the implementation of Historical-Critical Pedagogy (HCP) in the curriculum of the municipal education network of Limeira-SP and its relationship with the Political Pedagogical Projects (PPPs) of rural schools, considering the specificities of this educational context. The study is based on the assumption that, in a scenario marked by neoliberal policies in education, the Common National Curriculum Base (BNCC), guided by competencies and skills, significantly influences teacher training, teaching materials, and standardized assessments—elements that do not align with the principles of HCP. To analyze this issue, a qualitative approach was adopted, combining a literature review (theses and dissertations on HCP, curriculum, and Rural Education) and document analysis (Limeira’s municipal curriculum and the PPPs of rural schools). The results revealed that: (1) the municipal curriculum does not incorporate the particularities of Rural Education, reflecting a disconnect with the needs of this population; (2) the BNCC, as a hegemonic policy, subordinates pedagogical practice to meritocratic logics, limiting the effective implementation of HCP; and (3) while the PPPs make occasional references to HCP and Rural Education, they lack theoretical depth or concrete proposals. It is concluded that, although HCP is the official pedagogical approach of the municipal network, its materialization faces structural challenges, such as the predominance of the BNCC and the lack of specific curricular guidelines for Rural Education. Therefore, it would be pertinent to revise the municipal curriculum to include the specificities of Rural Education, alongside critical continuing teacher training, aiming to strengthen HCP as a transformative alternative to the neoliberal educational model.
Investigando o crescimento e a composição bioquímica de Chlorolobion lunulatum em escalas de 20 e 200 L
(Universidade Federal de São Carlos, 2025-04-25) Gonçalves, Maria Eduarda Costa; Lombardi, Ana Teresa; https://lattes.cnpq.br/6737850858443813; https://orcid.org/0000-0002-4299-3640; https://lattes.cnpq.br/1391729871680000; https://orcid.org/0009-0009-1560-7773
Green microalgae have attracted biotechnological interest due to their ability to accumulate value-added biomolecules, such as proteins, lipids, carbohydrates, and photosynthetic pigments. In addition to being efficient in converting CO2 and sunlight into biomass, Chlorophyta species can present high productivity per area and versatility in different environmental conditions. Among the promising species, Chlorolobion lunulatum stands out, still little studied, but with potential for expanded cultivation already demonstrated in the Laboratory of Algae Biotechnology, where this study was carried out. Our main objective was to evaluate aspects of the physiology of C. lunulatum in two cultivation systems of different scales: in a 20 L tubular photobioreactor and in 200 L raceway ponds. While in 20 L, the cultivations had controlled light intensity, in 200 L shade nets were used to mitigate the intensity of incident sunlight. At the end of the cultivation period, the contents of lipids, proteins and carbohydrates, and photosynthetic pigments in the biomass were determined. Growth rates were used to compare the crops, which were grown for ten days. The 200 L crops showed a higher specific growth rate (1.14 d-1), higher biomass production and higher levels of proteins (up to 23% DW), lipids (28% DW) and carbohydrates (16% DW), evidencing the viability of cultivation in larger-scale systems. On the other hand, the 20 L cultures showed significantly higher concentrations of chlorophyll a (10.51 mg L-1) and chlorophyll b (8.15 mg L-1), while the carotenoid concentration in the biomass did not show significant variation between 20 and 200 L. The data indicate that the tubular photobioreactor favored the synthesis of photosynthetic pigments, while the raceway favored the accumulation of biomolecules, such as proteins and lipids. Therefore, C. lunulatum presents biochemical characteristics that make it a promising candidate for industrial applications, especially in the energetic sector.