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Modelos de sobrevivência induzida por fragilidade da família PVF: uma abordagem bayesiana
(Universidade Federal de São Carlos, 2026-03-27) Pedraza, Carlos Franklin Taco; Opazo, Miguel Angel Uribe; https://lattes.cnpq.br/4179444121729414; https://orcid.org/0000-0001-8937-4815; Cancho, Vicente Garibay; https://lattes.cnpq.br/3503233632044163; https://orcid.org/0000-0002-0266-9141; https://lattes.cnpq.br/2973922801961193; https://orcid.org/0009-0000-6636-4198; Alvarez, Bernardo Moises Lagos; Santos, Daiane de Souza; Rodrigues, Gabriela Maria; Henriques, Marcos Jardel; https://orcid.org/0000-0001-5250-193X; https://lattes.cnpq.br/0929922667210546; https://orcid.org/0000-0002-1985-8141; https://lattes.cnpq.br/3011323408047031
In survival analysis, it is common to incorporate covariates such as age, sex, disease severity, among others. However, there are several unobserved factors that may also influence survival, including overall health status, lifestyle, occupation, or genetic predisposition. Such factors are often referred to as frailty and represent unobserved heterogeneity among individuals in the study. The objective of this work is to develop frailty models capable of capturing this unobserved heterogeneity in survival data. We introduce a new class of survival models that combines population unobserved heterogeneity and the presence of cured individuals through the incorporation of frailty terms from the PVF family (Power Variance Functions), referred to as PVF-Induced Defective (PVF-ID) models. This framework extends the classical theory of frailty models and defective lifetime models, allowing researchers to flexibly model the presence of long-term survivors. Inference is performed through a fully Bayesian procedure implemented via Hamiltonian Monte Carlo, while relevant frequentist properties are assessed through simulation studies. When applied to survival data related to HIV/AIDS, the model consistently identifies the effects of the covariates. Additionally, a bivariate survival model with cure fraction and frailty is proposed, based on Poisson mixtures and the PVF family. The model is extended to a regression framework, allowing the assessment of covariate effects on survival times. Inference is conducted under a Bayesian approach using Hamiltonian Monte Carlo implemented in RStan, and simulation studies are carried out to evaluate the performance of the estimators. The flexibility of the proposed structure allows the model to capture both dependence between failure times and unobserved heterogeneity. The practical utility of the model is illustrated using a real dataset.
Caracterização bioquímica e funcional de F-box like proteins em Leishmania infantum
(Universidade Federal de São Carlos, 2026-03-27) Regatieri, Wesley Klaysson Pereira; Teixeira, Felipe Roberti; https://lattes.cnpq.br/3568850159381693; https://lattes.cnpq.br/8184041108175983; https://orcid.org/0000-0003-1004-9708; Anibal, Fernanda de Freitas; Silva, Mariana Ferreira; https://lattes.cnpq.br/4918261968772806; https://lattes.cnpq.br/6153443508783625
A proteólise intracelular em eucariotos é mediada principalmente pelo Sistema Ubiquitina–Proteassoma (SUP), que envolve as enzimas E1, E2 e E3, sendo estas últimas responsáveis pelo reconhecimento dos substratos. Em protozoários parasitos, como Leishmania infantum, o SUP é essencial para adaptação ao ciclo de vida e sucesso do parasitismo, embora ainda seja pouco explorado, especialmente as E3 ubiquitina-ligases. Este estudo teve como objetivo caracterizar bioquimicamente e funcionalmente as proteínas F-box-like LinfFlp2 (LINF_240015400) e LinfFlp3 (LINF_150014400), adaptadores da E3 ubiquitina ligase LinfCRL1 de L. infantum. Parasitos expressando LinfFLP2-HA e LinfFLP3-HA foram submetidos à imunoprecipitação seguida de espectrometria de massas para identificação de proteínas associadas. Os interactomas revelaram 44 proteínas exclusivas para LinfFlp2, 125 para LinfFlp3 e 106 proteínas compartilhadas nos interactomas de LinfFlp2 e LinfFlp3, sugerindo redundância funcional. Para validação das interações em células HEK293T, os genes Replication protein A subunit (LINF_280024500), RNA-binding protein 29 – putative (LINF_180007200), Leucine-rich repeat protein – putative (LINF_340011100) e Putative mitochondrial carrier protein (LINF_020012000) foram clonados em vetores para expressão em células de mamíferos em fusão com myc no N-terminal. Ensaios de co-imunoprecipitação demonstraram que a proteína LRR é um potencial ligante de LinfFlp3. Em L. infantum, demonstramos através de CRISPR-Cas9 que as linhagens nocaute de LinfFLP2 não resultou em impacto no crescimento promastigota, enquanto não foi possível obter o nocaute completo de LinfFLP3, sugerindo caráter essencial. A inserção de uma cópia de LinfFLP3-HA no locus 18S ribossomal do parasito e posterior nocaute das duas cópias genômicas resultou em linhagem viável (DKO-LinfFLP3-HA), reforçando a essencialidade deste gene para L. infantum. O nocaute de uma das cópias do gene SKO LinfFLP3, DKO-LinfFLP3-HA e LinfFLP2-HA não apresentou alteração significativa de crescimento e não observamos alteração nas fases do ciclo celular das linhagens SKO-LinfFLP3 ou DKO-LinfFLP3-HA. Finalmente, análises de microscopia confocal demonstraram que LinfFlp2 e LinfFlp3 apresentam distribuição predominantemente citoplasmática granular e perinuclear com sutil localização nuclear. Em conjunto, os dados sugerem redundância funcional entre LinfFlp2 e LinfFlp3, ampliando a compreensão das LinfFlps na biologia de L. infantum.
Caracterização de superfícies texturizadas por vibração: análise de parâmetros de rugosidade e molhabilidade
(Universidade Federal de São Carlos, 2026-03-27) Moraes, Alvaro Araujo de; Antonialli, Armando Ítalo Sette; https://lattes.cnpq.br/4367459395417045; Moreira, Debora Carneiro; https://lattes.cnpq.br/4361739459398814; https://lattes.cnpq.br/5996514451614639; Suyama, Daniel Iwao; Watanabe, Flávio Yukio; https://lattes.cnpq.br/7240909307602526; https://lattes.cnpq.br/6492641614740181
Surface engineering has become an essential field for understanding how topographical characteristics influence the functional performance of materials in different applications, such as heat exchangers. Therefore, investigating the relationship between manufacturing parameters, machining vibrations, and variations in surface roughness parameters has attracted increasing scientific and technological interest. In this context, vibrations induced by actuators or inherent to machining processes can significantly alter surface morphology, resulting in surfaces with distinct characteristics depending on the process conditions. Thus, the present work aims to characterize flat machined surfaces of aluminum, brass, and stainless steel produced through turning and milling processes under different machining conditions, with emphasis on the analysis of roughness and wettability parameters. The characterization of the surface topology of the samples was carried out using confocal microscopy, evaluating the parameters of average roughness (Ra), skewness (Rsk), and kurtosis (Rku). Wettability analyses were performed using an optical tensiometer, enabling measurements of static, advancing, and receding contact angles, with distilled water used as the working fluid. The results obtained from turning indicated that, for all analyzed materials, samples produced under more severe machining parameters exhibited higher contact angles compared to surfaces manufactured under milder conditions. In contrast, the opposite behavior was observed for aluminum samples produced by milling, where higher contact angle values were associated with the higher speed condition corresponding to unstable machining. Overall, a consistent association was observed between the behavior of the skewness parameter and static contact angles, since in several cases where skewness varied, variations in static contact angle were also observed. These results contribute to the understanding of the influence of vibrations on the topographical characteristics of machined surfaces, supporting the correlation between manufacturing conditions, surface roughness, and wettability.
Concepções de controle dos frigoríficos brasileiros: uma análise sobre a JBS, Marfrig e Minerva
(Universidade Federal de São Carlos, 2026-03-27) Souza, Pedro Henrique de; Candido, Silvio Eduardo Alvarez; https://lattes.cnpq.br/0194644249955417; https://orcid.org/0000-0002-5275-6577; https://lattes.cnpq.br/7691056908112326; https://orcid.org/0009-0008-0885-2175; Donadone, Júlio César; Mundo Neto, Martin; https://lattes.cnpq.br/7643906508178259; https://lattes.cnpq.br/8118489647547095
This paper analyzes the transformations in the conceptions of control of the main companies in the Brazilian meatpacking companies: JBS, Marfrig, and Minerva, addressing how their strategies and management models were reconfigured in the context of the sector's consolidation and the financialization of the economy. The theoretical framework is based on Fligstein's economic sociology, especially the notion of conceptions of control. It engages with the literature on financialization and the Varieties of Capitalism approach, situating the Brazilian case within its specific institutional arrangement. It starts from the premise that conceptions of control express internal power dynamics within companies and their position in a field marked by disputes, state mediation, and market pressures. Methodologically, a multiple case study approach was adopted, analyzing the trajectory of the companies based on documentary analysis of corporate reports and corporate documents from 2007 to 2024. The investigation focused on dimensions such as acquisitions and mergers, shareholding composition, capital structure and leverage, profiles of the board of directors and management boards, and dividend distribution, allowing for a processual understanding of organizational transformations. The results indicate that the expansion of the companies, which became dominant in the national market and protagonists in the global protein trade, was driven by growth strategies via mergers and acquisitions, financed by leveraged capital structures and access to the stock market. The initial public offering (IPO) represented a turning point, redefining performance criteria and expanding the influence of institutional investors. A progressive professionalization of management and a reconfiguration of the role of the founding families were observed, in an environment increasingly driven by financial metrics. In terms of control concepts, the consolidation of shareholder value orientation was identified as the dominant principle throughout the analyzed period. The dynamics of the sector thus reveal a field of strategic action in which the State, companies, and investors interact, highlighting a hybrid form of financialization in Brazilian capitalism. It is concluded that the transformations in the conceptions of control of these corporations express broader changes in the organization of agro-export capitalism in Brazil, contributing to a critical understanding of financialization in emerging economies and its effects on governance and business action.
Uso do condicionamento operante como ferramenta de conservação ex-situ em instituições brasileiras
(Universidade Federal de São Carlos, 2026-03-27) Moraes, Caroline Rodrigues de; Schlindwein, Marcelo Nivert; https://lattes.cnpq.br/9690898537150950; https://orcid.org/0000-0001-8174-5941; https://lattes.cnpq.br/1785412307114204; https://orcid.org/0009-0007-3040-6676; Rocha, Vlamir Jose; Pizzutto, Cristiane Schilbach; https://lattes.cnpq.br/8044368595391973; https://lattes.cnpq.br/1622041882792235
Operant conditioning has become established as a strategic tool in the management of wild animals kept in ex situ conservation programs. This study investigated the practical application of operant conditioning in Brazilian institutions (zoos, wildlife triage and rehabilitation centers, breeding facilities, among others), analyzing the profile of training protocols, their purposes, and the technical limitations faced. The methodology consisted of a literature review and the application of a diagnostic form, preceded by a pilot study to validate and refine the instrument, which was subsequently applied to 201 institutions, of which 29 responded (30 including the pilot).The results indicate that operant conditioning is widely used in Brazilian ex situ conservation institutions, being implemented in 70% of the participants and under development in an additional 16.7%. Its application is mainly concentrated on large mammals and birds, particularly felids, primates, and psittacine, revealing marked taxonomic selectivity to the detriment of reptiles and invertebrates. Operant conditioning is primarily employed to facilitate daily and veterinary management, promote animal welfare, and reduce the need for physical and chemical restraint, with a predominance of positive reinforcement techniques. Although most institutions report having trained professionals, the lack of specialized technical training and the absence of systematic behavioral assessments, such as the use of ethograms, represent significant limitations. It is concluded that, despite its strong potential as a management and conservation tool in Brazil, operant conditioning still requires greater technical standardization and broader taxonomic application to be consolidated as a robust strategy for animal welfare, rehabilitation, and wildlife release.
Avaliação da contaminação por microplásticos no processo produtivo de queijos
(Universidade Federal de São Carlos, 2026-03-27) Avancini, William Faneca; Waldman, Walter Ruggeri; https://lattes.cnpq.br/0616238673458322; https://orcid.org/0000-0002-7280-2243; https://lattes.cnpq.br/2215613043098121; https://orcid.org/0009-0000-5840-6351; Waldman, Walter Ruggeri; Silva, Joelen Osmari da; Cacuro, Thiago Aguiar; https://lattes.cnpq.br/4782607993099360; https://lattes.cnpq.br/4160538990374188; https://orcid.org/0000-0003-4436-7691; https://orcid.org/0000-0003-1697-5075
The detection of microplastics in dairy matrices presents complex analytical challenges due to the density of lipids and proteins. Given these technical limitations, this research shifted the investigative focus from end-product analysis to mapping vulnerabilities within the production process. The objective of this study was to identify and evaluate critical points of microplastic contamination in the cheese manufacturing chain using a qualitative and descriptive approach. The methodology consisted of a comparative case study involving industrial units in Brazil and three strategic hubs in the European Union: the Netherlands, Spain, and Italy. The results allowed for the categorization of risks based on mechanical, thermal, and chemical stresses of polymers in contact with food. It was identified that extreme automation (Netherlands) and pressing time (Spain) are relevant vectors, but the highest criticality lies in industrial slicing and grating (Italy), where the increased plastic-to-food contact area enhances physical migration. The study concludes that the Brazilian regulatory framework presents a "blind spot" by focusing primarily on chemical stability while neglecting the physical degradation of equipment. The adoption of preventive replacement protocols for polymeric materials is recommended to mitigate the accidental ingestion of microparticles by consumers.
Trajetórias políticas e o perfil das vereanças em Sorocaba/SP.
(Universidade Federal de São Carlos, 2026-03-27) Tomoto, Thiago Hideo; Alves, Mariana Faiad Batista; https://lattes.cnpq.br/3951073428352583; Santos, André Cordeiro Alves dos; https://lattes.cnpq.br/2131880667704281; https://orcid.org/0000-0001-6323-5200; https://lattes.cnpq.br/2017735012245944; https://orcid.org/0000-0002-9840-5107; Ginzel, Flávia; Mota Junior, Vidal Dias da; https://lattes.cnpq.br/1845562576120800; https://lattes.cnpq.br/7645928463852577
Analyzing institutional politics in Brazil requires an examination of its past as a means to understand the present and envision possibilities for "other futures." It is fundamental, therefore, to recover the profiles of representatives who have occupied decision-making spaces and to identify the interests and objectives that permeated the sphere of institutional political representation. Consequently, understanding the profiles of city councillors (vereadores) in Sorocaba/SP, within a timeframe beginning in 1948, constitutes the central object of this thesis, which seeks clues to understand institutional political dynamics.The focus on Sorocaba’s local legislature is configured not merely as a research possibility, but as a recovery of the author's own political trajectory within the city. This lived experience becomes an investigative tool intertwined with scientific research, structured under rigorous sociodemographic analysis, fieldwork, and theoretical foundation. Thus, examining the locality from this perspective serves as a strategy to identify potential generalizations that assist in understanding electoral dynamics at state, national, and global levels. The recovery of these dynamics at the territorial level allows for an understanding of the vestiges of the roots that forge the relations between representatives and the represented. The identification of phenomena such as coronelismo (colonelism), mandonismo (bossism), and clientelism - and their developments through the lenses of the "legislator," the "procurer," and the "welfare provider" - comprises the framework chosen by the author to categorize, based on semi-structured interviews, the councillors elected for the first time in the 2024 elections. Furthermore, this study seeks to demonstrate how this modus operandi perpetuates itself, alongside the hypothesis of an emerging new group, termed by the author as the "personalist" group. This profile does not necessarily maintain a bond with the territory, a party project, or a political party; rather, it fosters a direct identification with the voter through themes that transcend local jurisdiction and the traditional role of the councillor, mediated primarily by social networks. Finally, the study reflects upon the profiles of councillors in Sorocaba/SP, emphasizing variables such as gender, race, religion, and marital status, in search of investigative evidence on how these new profiles may reorganize the dynamics of institutional politics.
A nossa luta é essa: uma etnografia com as lutas de moradores(as) removidos(as) pelo Programa de Urbanização de Favelas numa área entre a favela de Heliópolis e São João Clímaco
(Universidade Federal de São Carlos, 2026-03-27) Guidotti, Marcos Vinícius Silva; Villela, Jorge Luiz Mattar; https://lattes.cnpq.br/8301325600502054; https://orcid.org/0000-0001-5240-4654; https://lattes.cnpq.br/6165756473470045; https://orcid.org/0000-0003-3200-1190; Rizek, Cibele Saliba; Toledo, Luiz Henrique de; Martinez, Mariana Medina; Nascimento, Silvana de Souza; https://lattes.cnpq.br/0540870380815135; https://lattes.cnpq.br/5366260223109463; https://lattes.cnpq.br/9126534946585241; https://lattes.cnpq.br/0383359382532310
In this research, conducted in the area of the Heliópolis favela and the São João Clímaco neighborhood (southern zone of São Paulo), an ethnographic study was carried out on the effects of the national policy of recent decades aimed at combating precarious settlements – understood from the development of the Favela Urbanization Program – specifically its housing and social interventions. To achieve this objective, the thesis is structured into five chapters that articulate theoretical, documentary, and ethnographic analysis. The first chapter ethnographically reconstructs the formation of the field of urban studies, demonstrating how the central lens defining favelas as spaces of precarious housing was consolidated, focusing on the theoretical/discursive bases that would later be assimilated by the national public housing policy studied. The second chapter specifically examines the transition of this alignment between the theory of urbanization (of large cities) and housing policies, analyzing the theoretical-political fold through which the critical diagnosis of the unequal city – forged in the struggles against the military dictatorship – was converted into housing management technology, focusing on the description of how this academic knowledge underpinned the national policy to combat precarious settlements in urban Brazil (materialized in the Favela Urbanization Program). The third chapter introduces the ethnographic perspective of the research field, describing the historical action of residents who formed the local social movement in the Heliópolis region and their influence on the territorialization of the Favela Urbanization Program's intervention, explaining how local housing struggles were both recognized and resignified by the Program. The fourth chapter complicates this understanding by presenting other voices, knowledges, and housing arrangements that escaped the standardizing planning of the Favela Urbanization Program, pointing to the diversity and complexity of the ways of living in the favela that were obscured by the housing intervention studied. Finally, the fifth chapter focuses on the concrete experience of removal and waiting resulting from the intervention, detailing ethnographically how the lives of residents of the studied area were transformed by forced displacement, dependence on housing assistance programs, and prolonged uncertainty regarding the housing promised with the development of the Favela Urbanization Program; which, according to statements gathered in the research, produced a new form of vulnerability. The research, based on intensive fieldwork and bibliographic and documentary research, made it possible to confront the official project of the city with the understandings of struggle held by the population objectified by that project. The thesis concludes that urban interventions such as the Favela Urbanization Program, by ignoring the complexity, history, and disputes inherent in the ways of living in favelas, not only fail to solve housing problems but often intensify them, demanding from favela residents constant reinventions of their struggles for the right to housing and to live in the city.
Capacidade resistente de vigas celulares mistas de aço de alta resistência e concreto à instabilidade no montante da alma
(Universidade Federal de São Carlos, 2026-03-27) Ferreira, Lucas Gomes; Ferreira, Felipe Piana Vendramell; https://lattes.cnpq.br/5933034803347448; https://orcid.org/0000-0001-8007-789X; Nardin, Silvana de; https://lattes.cnpq.br/5587716781980132; https://orcid.org/0000-0002-8736-4987; https://lattes.cnpq.br/5991867134405037; https://orcid.org/0009-0005-4867-0788; Milani, Margot Fabiana Pereira; Rossi, Alexandre; https://lattes.cnpq.br/9324192204449423; https://lattes.cnpq.br/3946998323160911; https://orcid.org/0000-0001-6432-3931; https://orcid.org/0000-0001-9590-1554
This study aims to investigate the resistance capacity of high-strength steel composite cellular beams with concrete slabs against web-post buckling. To this end, nonlinear geometric and material analyses were performed using the ABAQUS® software. The numerical model was validated against experimental data from physical models of composite cellular beams with concrete slabs. Four reference models were used as a basis for a parametric study carried out in two stages. In the first stage, the influence of the steel yield strength was investigated for S460, S690, and S960 steels (with yield strengths of 460 MPa, 690 MPa, and 960 MPa, respectively), without geometric variations. In the second stage, variations in steel strength were combined with variations in the following ratios: the opening diameter to the unexpanded steel profile height (Do/d), taking values of 0.8, 0.9, 1.0, and 1.1; and the center-to-center spacing to opening diameter ratio (p/Do), taking values of 1.2, 1.3, 1.4, and 1.5. For the variations of the validated symmetric profile models, CCB1 from Nadjai et al. (2007) and CCB3 from Müller et al. (2006), as well as the asymmetric model CCB2 (asymmetry ratio of 1.13) also from Nadjai et al. (2007), web-post buckling remained the predominant failure mode across all steel grades during the first stage, with maximum strength gains ranging from 24.6% to 60.8% for S690 and from 54.0% to 83.4% for S960. For variations of model CCB4, also from Müller et al., (2006), which has a top-to-bottom tee asymmetry ratio of 2.8, only local web buckling of the top tee was observed in the first stage, regardless of yield strength, with strength gains of 28% for S690 and 68% for S960. In the second stage, increasing Do/d tended to reduce the maximum strength, while increasing p/Do generally increased it, although complex interactions between geometry and steel yield strength were observed. For the CCB1, CCB2, and CCB3 variations, as steel strength increased, failure modes shifted toward those involving the formation of Vierendeel plastic mechanisms, either in isolation or combined with web-post buckling. For the CCB4 variations, the failure mode shifted from pure local web buckling of the top tee to an interaction between this failure mode and the Vierendeel plastic mechanism. The numerically obtained maximum strength values were compared with four analytical verification models: Panedpojaman et al. (2014), Grilo et al. (2018), AISC Steel Design Guide 31 (2016), and BS EN 1993-1-13 (2024). The comparison shows that most formulations underestimate the maximum resistance capacity of high-strength steel–concrete composite cellular beams. When analyzing the effect of increasing steel yield strength on maximum strength, the AISC Steel Design Guide 31 (2016) method showed an increase in the F_numerical/F_analytical ratio, while the other methods showed a decrease in this ratio as strength increased. Furthermore, all methods exhibited high coefficients of variation, often exceeding 40%, indicating high relative data dispersion. This level of variability compromises the reliability of predictions for high-strength steels, suggesting that current formulations do not adequately capture the instability and plastification phenomena in composite cellular beams with high-strength steel profiles.