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    Mecânica newtoniana, equações de Maxwell e as transformações de Lorentz
    (Universidade Federal de São Carlos, 2025-12-10)
    Oliveira, Karolina Kathallyn Silva de
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    Seixas, Wladimir
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    http://lattes.cnpq.br/1697352974728327
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    https://orcid.org/0000-0002-0843-3500
    This work develops a mathematical and conceptual analysis of the transition from Newtonian Mechanics to Special Relativity, emphasising the formal structures underpinning each theory and the reasons that make the relativistic reformulation of space and time necessary. Aimed at an audience with a mathematical background, it seeks not only to present the physical results, but also to illuminate the algebraic and geometric structures that enable this theoretical reformulation. In the first part, Classical Mechanics is presented in the light of vector formalism and analytic geometry, discussing the concepts of absolute space, absolute time, laws of motion, reference frames, and conserved quantities. Subsequently, Electromagnetism is introduced through Maxwell’s equations, the interpretation of light as an electromagnetic wave, and the description of electric and magnetic fields. This analysis highlights the incompatibility between Galilean relativity and the invariance of Maxwell’s equations, a conflict empirically reinforced by the Michelson–Morley experiment. From this conceptual crisis, the work proceeds to the second part, devoted to the formulation of Special Relativity. Einstein’s postulates, Lorentz transformations, and the structure of space-time are introduced, presenting fundamental relativistic quantities such as proper time, four-vectors, the electromagnetic tensor, and the Minkowski metric. It is shown how the classical concepts of momentum, energy, and force are reformulated within the new theoretical framework, as well as the covariant form of Maxwell’s equations, which acquire elegance and geometric coherence within the tensor formalism. Finally, some applications and consequences of modern physics are discussed, highlighting phenomena and technologies whose understanding depends directly on Relativity, such as global positioning systems (GPS), high-energy processes in particle physics, properties of electromagnetic fields and waves, and the foundations of contemporary astrophysics. Thus, the work demonstrates that Special Relativity does not replace Classical Physics, but rather generalises it in a consistent manner, preserving it as a limiting case and integrating mechanical and electromagnetic descriptions within a single conceptual and mathematical framework. In conclusion, this work emphasises that Special Relativity emerged not merely as a theoretical correction, but as a natural consequence of a deeper mathematical conception. By presenting the concepts and derivations with formal precision, it is hoped that this work contributes to a clearer mathematical understanding of this conceptual leap.
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    “O Tempo e a Constância”: reflexão sobre uma trajetória acadêmica na medicina
    (Universidade Federal de São Carlos, 2026-09-30)
    Zanatta, Ricardo Patrezi
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    Ferreira, Esther Angélica Luiz
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    http://lattes.cnpq.br/4054544728456101
    This work is a reflective portfolio documenting the author's journey through the Medicine program at the Federal University of São Carlos (UFSCar), aiming to answer the question: "Did I manage to contribute to the UFSCar Medicine program being in a better state when I left than when I started?" The introduction outlines a career choice born not of an early calling, but of curiosity and gradual discovery, following the decision to abandon plans to pursue other fields of study. Upon admission, the ambition to leave the UFSCar program at a higher level than he found it became the guiding principle of his university experience. The results describe—in descending order of time commitment—the author's main areas of involvement: the Athletic Association (*Atlética*), where he held various roles over six years, developing skills in organization, leadership, communication, and problem-solving; over 20 extension projects, viewed as a way to give back to society for the investment received; four undergraduate research projects, collaborations on other studies, and conference presentations, resulting in two awards; a research internship in Toledo, Spain, in 2024—the fulfillment of a long-held dream; and elective internships, which marked the transition from curiosity to professional practice. The text also highlights human capital—comprising faculty, staff, and students—as UFSCar’s greatest asset, acknowledging the individuals who shaped the author's education. The discussion reveals that non-technical skills, teamwork, and giving back to the university are central elements of medical training. The conclusion notes that it is impossible to state definitively whether the goal of elevating the program's standing was actually achieved; that assessment will be left to time and future generations. However, the author concludes his undergraduate studies satisfied with the effort dedicated to this endeavor and grateful for the relationships built.
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    Letramento racial e educomunicação na escola pública estadual: a produção audiovisual como expressão do protagonismo juvenil no ensino médio
    (Universidade Federal de São Carlos, 2026-08-27)
    Ferreira, Pedro Henrique Eneas
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    Sousa, Maria do Carmo de
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    http://lattes.cnpq.br/6637658562543505
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    https://orcid.org/0000-0002-5523-757X
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    http://lattes.cnpq.br/6448956503410540
    Inspired by the idea that historically silenced subjects need to narrate their own stories, this dissertation understands narrative as a political, formative, and epistemological act in response to school and media traditions that have historically erased Black voices and experiences. The research was guided by the following question: how can audiovisual production, grounded in the principles of educommunication and guided by an anti-racist and decolonial perspective, express the youth protagonism of high school students? The general objective was to analyze audiovisual production as an expression of youth protagonism among high school students, based on the Nossas Narrativas project, developed in a public state school in the interior of São Paulo, Brazil. The project involved the production of podcast episodes and audiovisual materials addressing memory, identity, representation, epistemicide, and youth protagonism. Methodologically, this is a qualitative study, configured as a single embedded case study and articulated with a quantitative-descriptive diagnostic stage. The investigative process involved the analysis of a diagnostic questionnaire applied by the Student Council to 282 students, the constitution of the participant group, an educommunication and racial literacy workshop, production meetings, podcast recordings, field diary, focus groups, individual interviews, document analysis, and systematization of the Educational Product. The final production group consisted of six students. Data analysis was conducted based on Content Analysis, in dialogue with the Baobab of Concepts, a theoretical-analytical matrix constructed to articulate coloniality of knowledge, epistemicide, critical racial literacy, educommunication, audiovisual production, youth protagonism, and empowerment. The analytical triangulation, guided by five theoretical propositions and by the methodological procedures of the case study, resulted in differentiated verdicts: three propositions were supported with qualification, one was supported with methodological reservation, and one was partially supported. The data indicate that audiovisual production, when guided by anti-racist pedagogical intentionality, enabled participants to name erasures, formulate questions, interview Black reference figures, control narrative devices, and publicly circulate their productions. Three central analytical axes were identified: narrative sovereignty, Black intellectuality on scene, and supportive horizontality. The individual interviews indicated subjective and formative shifts in the participant subgroup, especially in the way they recognized Black references, interpreted the school, and understood their own position in the production of narratives. However, the study design does not allow for longitudinal monitoring of the permanence of these shifts nor for statistical generalizations to non-comparable contexts. As a practical contribution, the Educational Product Nossas Narrativas was developed, consisting of a digital repository and an educommunication and podcasting guide aimed at Basic Education teachers. The study argues that anti-racist education is not consolidated through isolated actions, since it requires continuity, collective elaboration and openness to silences and to different rhythms of participation.
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    Influência da vigilância ativa dos contatos na cascata de cuidado da tuberculose latente
    (Universidade Federal de São Carlos, 2026-07-17)
    Nunes, Tatiana Santos Malheiros
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    Souto, Bernardino Geraldo Alves
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    http://lattes.cnpq.br/7264826508407685
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    https://orcid.org/0000-0003-4083-3050
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    http://lattes.cnpq.br/3937279423127168
    Eliminating tuberculosis as a public health problem is necessary and possible, but it has faced operational and other challenges in healthcare services and public policies. One of the strategies to eliminate the disease, which currently has low coverage in the city of Teresina-PI, is the treatment of Latent M. tuberculosis Infection (LTBI). To help with this, an alternative model for monitoring and tracking the Latent Tuberculosis Care Cascade (LTCC) was proposed and tested, aiming to increase healthcare coverage for LTBI. Through a longitudinal intervention study, a controlled, paired, and randomized operational trial was conducted. Fifty-two contacts of laboratory-confirmed bacilliferous tuberculosis cases from 11 Primary Health Care Units (PHUs) in Teresina - Piauí were followed using this alternative model, which consisted of standardized guidance recorded in the Citizen’s Electronic Health Record (PEC) in real time for each of the steps of CCTL. In 11 other UBS in the same health region, the conventional surveillance model was maintained over 27 contacts. In the 22 UBS, demographic data of these contacts and a set of care coverage indicators at each step of CCTL were collected. The indicators collected in the group of UBS where the new surveillance strategy was applied were statistically compared to the same indicators in the group of UBS where the conventional model was maintained. Of the total people studied, most were female and of black race/color. The average age was 33.5 years. The proportion of contacts who had a chest X-ray, who took the 1st tuberculin test and the 2nd tuberculin test when indicated, who were fully examined and who started preventive tuberculosis treatment was higher in the UBS where the alternative active CCTL surveillance model was applied. A statistically significant difference (p < 0.05) was reached in the indicators: proportion of contacts who underwent chest X-ray, who undergo the 2nd tuberculin test when indicated, and the proportion of contacts fully examined. This result showed that the tested model is effective in helping fight tuberculosis because it significantly increases healthcare coverage for latent TB infection.
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    Estudo comparativo de métodos de seleção de modelos para redes aleatórias
    (Universidade Federal de São Carlos, 2026-08-31)
    Molina, Felipe Baptistao Durante
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    Cerqueira, Andressa
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    http://lattes.cnpq.br/1934493281651316
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    https://orcid.org/0000-0003-3803-9253
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    http://lattes.cnpq.br/1871537351531299
    In recent years, complex networks have been widely used to model systems with objects of interest, called vertices, which interact with each other by a haracteristic or relationship, represented by an edge. Through the various uses of complex networks, community detection has a great importance in the field, aiming to group vertices into the same cluster based on a given similarity between them. Thus, several models have been proposed to perform the clustering, assuming the number of communities is known previously, but this assumption is not always acceptable in real-world data. Therefore, in this work, we address the case of an unknown number of communities, that is a model selection problem, where a study has been conducted to compare selection methods for the Stochastic Block Model, including proposed methods based on normalized maximum likelihood and computationally approximated