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Aspectos sobre a História e Filosofia da Ciência relacionados ao tópico Gravitação presentes em livros didáticos de Física aprovados pelo PNLD 2018
(Universidade Federal de São Carlos, 2026-07-13) Idra, Gustavo Henrique Alcantara; Moraes, Leticia Estevão; http://lattes.cnpq.br/4358189417039369; https://orcid.org/0000-0001-8245-6172; Gebara, Maria José Fontana; http://lattes.cnpq.br/6585493065968961; https://orcid.org/0000-0002-9399-3683; https://lattes.cnpq.br/9445153804302596; https://orcid.org/0009-0000-2749-9524
The History and Philosophy of Science (HPS) is an important approach in Physics Education because it helps students reflect on how scientific knowledge is built, its historical development, and different views of the Nature of Science (NOS). In this context, textbooks play a key role in bringing these ideas into the classroom, making it important to investigate how HPS is presented in these materials. Recent studies have examined historical and epistemological aspects in Science and Physics textbooks, pointing out both advances and gaps in the way historical context and views of science are presented. Based on this scenario, the present research sought to answer the following question: “Which aspects of the History and Philosophy of Science related to astronomical models and scientific anecdotes are found in Physics textbooks approved by the 2018 National Textbook Program (PNLD)?”. Thus, the objective of this study was to analyze aspects of the History and Philosophy of Science related to astronomical models and scientific anecdotes present in Physics textbooks approved by the 2018 PNLD, focusing on the topic of Gravitation. This is a documentary study with a qualitative and exploratory approach, based on the analysis of selected chapters from the twelve Physics textbook collections approved by the program. The analysis focused on two categories: the cosmological models presented in the textbooks and the scientific anecdotes related to the development of Gravitation. The results showed that all textbook collections discuss the historical transition from the geocentric model to the heliocentric model, although with different levels of depth and historical context. The analysis also showed that visual representations are mainly limited to these two models, with little reference to other cosmological models and a strong Eurocentric view of the History of Astronomy. Regarding scientific anecdotes, the story of Newton's apple was found in most of the textbooks and was presented in an ambiguous way. Although many authors discuss the historical accuracy of the episode, it may still encourage simplified views about how scientific knowledge is developed. Overall, the textbooks analyzed include HPS elements that can contribute to Physics teaching, but these elements are still presented only partially. The results suggest opportunities to improve the historical and epistemological treatment of these topics and may support future studies as well as the development of new educational materials.
Estudos in vivo da atividade antitumoral de uma desintegrina inibidora da integrina αvβ3
(Universidade Federal de São Carlos, 2026-07-07) Almeida Junior, Paulo Cesa; Lino, Rafael Luis Bressani; http://lattes.cnpq.br/9514190453774618; Selistre-de-Araujo, Heloisa Sobreiro; http://lattes.cnpq.br/4065824911933203; https://orcid.org/0000-0002-2372-7814; http://lattes.cnpq.br/4742126034489479
Cancer represents a complex ecosystem composed of tumor cells and a diverse population of non-malignant cells embedded within an altered extracellular matrix. The tumor microenvironment (TME) comprises various immune cell types, cancer-associated fibroblasts, endothelial cells, pericytes, and several additional tissue-resident cell populations. These host cells were once regarded as mere bystanders in tumorigenesis but are now recognized as playing critical roles in cancer pathogenesis. During vascular remodeling and angiogenesis, for example, endothelial cells upregulate the expression of several cell-surface molecules that promote tumor cell invasion and proliferation, including integrin αvβ3. Integrin αvβ3 is a vitronectin receptor that recognizes the adhesive motif RGD and plays an essential role in directing cell migration. Our group has previously investigated this integrin using the recombinant disintegrin DisBa-01, derived from Bothrops alternatus venom and produced as a His-tag recombinant protein through heterologous expression and purification. The aim of the present study was to evaluate the potential effects of the pharmacological inhibition of integrin αvβ3 on angiogenesis and tumor progression in a syngeneic experimental model of triple-negative breast cancer. The effects of local and systemic inhibition of integrin αvβ3 on primary tumor development were evaluated in female BALB/c mice inoculated with 4T1Br4-mCherry cells. Following tumor establishment, the animals were allocated into two experimental models (Non-surgical Spontaneous Metastasis and Surgical Spontaneous Metastasis), each comprising three groups (Control Group 1, DisBa-01 Group, and Control Group 2), and were treated for a defined period. After euthanasia, tissue samples from multiple organs were collected for subsequent real-time quantitative PCR, histological, and immunofluorescence analyses. The study was approved by the Animal Ethics Committee of the Federal University of São Carlos under protocol number 9550180823. The results demonstrated that pharmacological inhibition of integrin αvβ3 by DisBa-01 modulated the tumor microenvironment, producing both pro-tumorigenic and antitumor effects in both experimental models. Increased collagen deposition was observed in tumors from Experiment 1, whereas a greater potential for tumor recurrence was detected in the DisBa-01-treated group in Experiment 2. In addition, reduced pulmonary metastasis was confirmed by qPCR in both experiments. Comparatively, animals that did not undergo surgery exhibited a better therapeutic response, whereas the surgical model showed greater metastatic dissemination and reduced survival. Collectively, these findings indicate that inhibition of integrin αvβ3 alone was insufficient to restrain tumor progression in vivo, highlighting the need for further studies to elucidate its relationship with the tumor microenvironment.
Ajuste de modelos de Cox e de florestas aleatórias em análise de sobrevivência
(Universidade Federal de São Carlos, 2025-12-01) Melo, Mathews Siqueira; Martins Dias, Teresa Cristina; http://lattes.cnpq.br/0187724276640668; http://lattes.cnpq.br/1753543115560585
This final course project explores the application and comparison of classical statistical methods and machine learning in the context of survival analysis. A detailed theoretical review of the fundamentals of time-to-event data analysis was conducted, addressing concepts such as censoring, survival and hazard functions, the non-parametric Kaplan-Meier estimator, and the Cox semiparametric proportional hazards model. In parallel, the principles of machine learning were studied, focusing on the structure of decision trees and the robustness of ensemble methods, such as random forests. To evaluate the performance of the models, consolidated metrics were used, including the C-index for discrimination, the Brier score for probabilistic accuracy, and metrics derived from the confusion matrix, such as accuracy, sensitivity, and specificity. The practical application of the methodologies was carried out through two case studies: the first, with real data from a clinical study, illustrated the workflow for the adjustment and validation of a Cox model; A second experiment, using simulated data, allowed for a direct comparison of the predictive performance between an optimized decision tree and a random forest in a controlled scenario. The results highlight the contrast between the interpretability of classical models and the predictive performance of machine learning models, discussing the scenarios in which each approach may be more advantageous.
Análise de biclusterização em células únicas
(Universidade Federal de São Carlos, 2026-06-26) Duarte, Pedro Henrique; Zuanetti, Daiane Aparecida; http://lattes.cnpq.br/8352484284929824; https://orcid.org/0000-0003-1591-959X; http://lattes.cnpq.br/6479064504028654; https://orcid.org/0000-0003-1591-959X
The single-cell analysis has gained prominence in the last few years, propelled by technological advances that made RNA sequencing more accessible and reduced information loss. Initially, due to technical limitations, sequencing was performed in bulk: RNA was extracted from a sample composed of multiple cells, resulting in an average gene expression profile. This method allowed comparisons between healthy and diseased tissues, or between different experimental conditions, based on average gene expression. However, this approach didn’t capture the cellular heterogeneity within the same tissue. With the advent of single-cell RNA sequencing, it became possible to analyze each cell of the sample individually, enabling the identification of cell subpopulations and characterization of subtle variations among cells from the same region, something specially relevant in tissues with high cellular diversity, like the brain. Despite its advantages, single-cells data presents specific challenges, such as high levels of noise, a large proportion of zeros (sparsity) and high dimensionality, since each cell is described by thousands of genes. In this study, normalization techniques were explored to process the data and reduce the impact of technical effects, as well as biclustering methods to simultaneously group cell with similar profiles and the most expressive genes in each group. To this end, a gene expression dataset composed of 18,928 genes and 734 cells derived from the human fetal brain and cerebral organoids obtained at different developmental stages was analyzed. The normalization was able to reduce the effects of technical variation by detecting relevant genes with low expression levels, while biclustering enabled the simultaneous identification of groups of cells with similar expression profiles and the most representative genes within each group. The results indicated that more mature organoids exhibit greater similarity to fetal cells, although they still do not fully reproduce all the characteristics of the human fetal brain.
Democracia, comunicação científica e plataformas digitais: as artes como mediação ética e transformadora do conhecimento
(Universidade Federal de São Carlos, 2026-06-15) Manzini, Mariana; Ribeiro, Renilson Rosa; http://lattes.cnpq.br/4919452710416508; https://orcid.org/0000-0002-2809-1376; http://lattes.cnpq.br/2471152208842772
This article discusses the relationships between democracy, scientific communication, and the arts, analyzing how artistic practices can function as forms of mediation, humanization, and democratization of knowledge in contemporary contexts marked by structural inequalities and the logic of digital platforms. Drawing on an interdisciplinary approach, it brings together contributions from communication studies, sociology, philosophy, anthropology, and critical education to examine the effects of contemporary capitalism on emotions, knowledge production processes, and regimes of symbolic circulation. The text mobilizes the song “Marujo” by the band Puro Suco, as well as elements of Brazilian popular culture, especially the figure of Iara, as metaphors for the experience of knowledge understood as a collective journey, traversed by tensions, displacements, and possibilities of social transformation. It argues that scientific communication must move beyond strictly technical models, incorporating cultural, aesthetic, and emotional dimensions capable of broadening access to knowledge, strengthening democratic practices, and fostering more inclusive forms of social participation.