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Análise da eficiência na educação dos municípios paulistas entre 2017 e 2021: uma abordagem não paramétrica
(Universidade Federal de São Carlos, 2026-01-28) Silva, Aron Momberg da; Santana, Naja Brandão; https://lattes.cnpq.br/4950197164940762; Rodrigues, Rodrigo Vilela; https://lattes.cnpq.br/7066100737307566; https://lattes.cnpq.br/1425350081219771; https://orcid.org/0009-0000-0356-044X; Rodrigues, Rodrigo Vilela; Reis, Janderson Damaceno dos; Gomes, Alexandre Lopes; https://lattes.cnpq.br/7066100737307566; https://lattes.cnpq.br/0648522809346485; https://lattes.cnpq.br/5002157193962189
The present study evaluated the efficiency in the management of resources allocated to basic education in municipalities within the state of São Paulo, addressing the problem of allocative inefficiency where increases in per-pupil spending do not necessarily reflect improvements in educational indicators. To this end, Data Envelopment Analysis (DEA) was employed using the BCC model with variable returns to scale, alongside the inverted frontier method and a composite index to ensure a precise differentiation of all analyzed municipalities between 2017 and 2021. By modeling the relationship between socioeconomic and financial inputs relative to IDEB performance, the study sought to investigate the influence of population size and the adaptability of school networks in the face of exogenous shocks, such as the Covid-19 pandemic, providing evidence on the importance of technical management over budgetary expansion.
Cohomologia de Cech e gerbes
(Universidade Federal de São Carlos, 2026-01-28) Morais, Laurinda Aparecida Ferreira de; Ruffino, Fabio Ferrari; https://lattes.cnpq.br/2512107188781159; https://orcid.org/0000-0002-8607-3715; https://lattes.cnpq.br/4093179250656591; https://orcid.org/0009-0001-9046-9616; Henni, Abdelmoubine Amar; Dalbelo, Thaís Maria; https://lattes.cnpq.br/2745843382864439; https://lattes.cnpq.br/8872438977518818
The investigation for global properties of mathematical objects often relies on an understanding of their local behavior. However, when one attempts to assemble local data from different regions of a space, obstructions may rise, revealing intrinsic topological information about the space itself. Sheaf Theory organizes mathematical information defined on local regions, while Cech Cohomology measures when this local information cannot be consistently combined to form a global object. This work develop these theories, starting from categorical foundations, including monoidal categories and 2-categories, and advancing toward sheaf theory and Cech cohomology. Subsequently, these tools are applied to the study of vector bundles, presenting a geometric model for the first Chern class, which arises within the context of Cech cohomology as the class that classifies complex line bundles up to isomorphism, thus providing a geometric interpretation of the cohomology group $H^2(X, \mathbb{Z})$. Finally, we introduce gerbes as structures that generalize line bundles within a 2-categorical framework. Using Cech cohomology and the language of 2-categories, it is described how gerbes relate to third-degree cohomology classes, offering a geometric model of $H^3(X, \mathbb{Z})$.
Espumação química de PVC rígido empregando azodicarbonamida e bicarbonato de sódio
(Universidade Federal de São Carlos, 2026-01-28) Gouvêa, Noélle Barbosa Favero; Bettini, Sílvia Helena Prado; https://lattes.cnpq.br/3687551763124327; https://orcid.org/0000-0001-6549-2980; Staffa, Lucas Henrique; https://lattes.cnpq.br/2896049826673626; https://orcid.org/0000-0002-6338-6903; https://lattes.cnpq.br/3111896432722216; https://orcid.org/0009-0004-3181-4426; Scuracchio, Carlos Henrique; ttp://lattes.cnpq.br/0896060959622431; https://orcid.org/0000-0002-7723-0213
Poly(vinyl chloride) (PVC) ranks third in the global production of thermoplastic polymers, and due to its long degradation time, it becomes essential to adopt strategies that reduce raw-material consumption in large-scale applications such as rigid sewer pipes. This study evaluated the chemical foaming of typical PVC formulations for sewage systems, comparing azodicarbonamide (pure and modified) and sodium bicarbonates, which present distinct decomposition kinetics, through incorporation in a torque rheometer and analyses of density, thermal characterization (TGA and DSC), scanning electron microscopy (SEM), mechanical testing, and compliance with technical standards. The results indicated that azodicarbonamide produced smaller and more uniform cells, with higher cell density, which translated into improved morphological control and greater expansion efficiency, particularly for the blowing agents Planagem CS-4M (10.5% expansion at 1.0 phr and 7.8% in manufactured pipes) and Planagem B-8 (4.3% at 1.0 phr and 2.9% in pipes). Sodium bicarbonates, although the most environmentally attractive option, generated more heterogeneous cells and yielded very low or null expansion (AO-653 with 1.0% and AO-421 with negative values), evidencing processing instability. Thermal and rheological analyses showed that the type of blowing agent influences the PVC crosslinking time, with azodicarbonamide accelerating the reaction while bicarbonates retard it, without altering the molar mass or the polymer’s thermal transitions, as confirmed by the K-value and DSC measurements. Overall, the morphological, thermal, and regulatory assessments demonstrated that azodicarbonamide-based systems are more suitable for rationalizing PVC consumption, combining significant expansion, thermal stability, and technical compliance, whereas sodium bicarbonates exhibited relevant limitations under the evaluated conditions.