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O Repositório Institucional da UFSCar (RI UFSCar) é um sistema de informação que visa armazenar, preservar, organizar e disseminar amplamente a produção intelectual dos diversos setores e segmentos da comunidade da UFSCar, provendo o acesso aberto à informação produzida na instituição e registrada como científica, tecnológica, didática, artístico-cultural e técnico-administrativa.

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Movimento social como resistência na universidade: processos de subjetivação em um coletivo de causas indígenas
(Universidade Federal de São Carlos, 2026-07-07) Oliveira, Tyfany Maia de; Martins, Mário Henrique da Mata; http://lattes.cnpq.br/5503003894437331; Yepá Mahsã; http://lattes.cnpq.br/4618296954486958
Universidade Federal São Carlos pahka bu’eturiakari wi’ipᵾ, mari ukũ tuhtuase turi na ma’mapiha bu’e wahakũ tuhtuase kahãsere i’ña behsewe, bu’ese ukũri turi ni. A’te i’ña behesewe bu’ese nisa, mari ñehkusᵾmᵾa, ahkawererã na ukũ, a’te pahka bu’ese wi’seripᵾ mari po’rã ke’rã bu’eato ni na ukũ ahpokuke. Toho wego a’tere i’ña behsewe bu’egotigo a’rã pᵾarã pehkasã pahka bu’ekarã na ohakukepu mipoteõnoapᵾ Manuel Castells toho nika Michel Foucault. Te bu’esere ohakugotigo na ma’mapiha mera nerenuhueha ukũ a’mesᵾo weke ni. Toho werã ni’kamukᵾse pᵾapika pe’ri pehase bu’erã mera da’ranoke ni. Naa mera ukũ, seriti’ña weka be’rore, ahpokũ ohanoawᵾ. Toho wekare maha topo’peapᵾre pa’paritise turi bahuawᵾ, te ni; a) Mari nisetise, mahsise, ukũse misanᵾkaeha ohakũ bue’se; b) Bu’eturiakã, ukũtuhua bu’enemokãse a’ti Pahirituri bu’ese niri wipᵾ; c) Ti bu’eri kura po’peapᵾre a’meri ma’i ehõpeo, wehepeose; d) ti bue’rikura añuro wahkũ, ukũtuhtua miasekahãse. A’te bu’e, nerenuha ukũ a’mesᵾoke meramaha nisa na mamapihare wahkũ tuhutuakã wese nisa, a’to Pahka Bu’eturiakãse weri wi’i po’peapᵾre.
Otimização de portfólios no mercado brasileiro: uma análise da robustez do modelo de Markowitz frente à diversificação ingênua via simulações computacionais
(Universidade Federal de São Carlos, 2026-07-07) Philippsen , Gabriel; Lopes Rosa , Beatriz; Rodrigues, Ariano De Giovanni; http://lattes.cnpq.br/4881530489438346; https://orcid.org/0000-0003-0294-6775; http://lattes.cnpq.br/4852671367681114; https://orcid.org/0000-0002-9140-4312
A otimização de carteiras segundo Markowitz (1952) enfrenta um obstáculo crítico na prática: a estimação dos parâmetros (retornos esperados μ e covariância Σ) a partir de amostras finitas introduz erros que degradam o desempenho fora da amostra. DeMiguel, Garlappi e Uppal (2009) demonstraram que a carteira 1/N (alocação igualitária) é competitiva em Índice de Sharpe frente a otimização formal. O presente trabalho amplia essa questão ao incorporar o Índice de Calmar, que enfatiza contenção de perdas de cauda, investigando em que dimensões de desempenho o Portfólio de Mínima Variância Global (PMVG) supera o 1/N no mercado brasileiro. A metodologia implementa backtest rolling mensal de ambas as estratégias no período janeiro/2015–dezembro/2025 utilizando 15 ações de alta liquidez da B3, com janelas de estimação variáveis (1, 3, 5 e 10 anos). O desempenho é avaliado por Índice de Sharpe, Calmar, CAGR, volatilidade e máximo drawdown. Resultados confirmam que 1/N domina em Sharpe em ambos os horizontes (2015–2019: 0,964 vs. 0,788; 2015–2025: 0,485 vs. 0,429), validando que erro de estimação em μ anula ganhos da otimização. A sensibilidade a janela de estimação revelou relação não-monotônica, com 3 anos produzindo desempenho ótimo. Contudo, em Índice de Calmar, a hierarquia se inverte: PMVG registra vantagem consistente (2015–2019: 1,313 vs. 1,162; 2015–2025: 0,598 vs. 0,544). Adicionalmente, PMVG apresenta volatilidade menor (16,11% vs. 20,75% em 2015–2025) e máximo drawdown menos severo (−29,5% vs. −38,2%). Conclui-se que a hierarquia entre estratégias é sensível ao critério: embora 1/N supere em retorno ajustado por volatilidade total, PMVG oferece proteção mensurável contra perdas de cauda, relevante para investidores conservadores. A escolha depende de qual critério alinha-se melhor com objetivos do investidor.Markowitz's portfolio optimization paradigm faces a critical practical obstacle: parameter estimation (expected returns μ and covariance Σ) in finite samples introduces estimation error that degrades out-of-sample performance. DeMiguel, Garlappi, and Uppal (2009) demonstrated that the equal-weight portfolio (1/N) without any estimated parameters is competitive in Sharpe Ratio against formal optimization strategies. This work extends that inquiry by incorporating the Calmar Ratio, which emphasizes tail loss containment, investigating in which performance dimensions the Global Minimum Variance Portfolio (GMVP) outperforms the 1/N allocation in the Brazilian stock market. The methodology implements monthly rolling backtests of both strategies over January 2015–December 2025 using 15 high-liquidity B3 stocks, with varying estimation windows (1, 3, 5, and 10 years). Performance is evaluated by Sharpe Ratio, Calmar Ratio, CAGR, annualized volatility, and maximum drawdown. Results confirm that the 1/N portfolio dominates the GMVP in Sharpe Ratio across both horizons (2015–2019: 0.964 vs. 0.788; 2015–2025: 0.485 vs. 0.429), validating that estimation error in μ annuls the theoretical gains of optimization. Sensitivity to the estimation window revealed a non-monotonic relationship, with a 3-year window producing optimal global performance. However, when the evaluative dimension is the Calmar Ratio, the hierarchy inverts: GMVP registers consistent advantage (2015–2019: 1.313 vs. 1.162; 2015–2025: 0.598 vs. 0.544). Additionally, GMVP exhibits lower volatility (16.11% vs. 20.75% over 2015–2025) and less severe maximum drawdown (−29.5% vs. −38.2%). We conclude that the hierarchy between strategies is sensitive to the evaluative criterion: while 1/N outperforms in total return-adjusted risk (Sharpe), GMVP provides measurable protection against tail losses, relevant for conservative investors. The choice depends on which criterion best aligns with the investor's specific objectives.
Análise do potencial da técnica de biospeckle laser aplicado como ensaio não destrutivo para a avaliação de germinação de sementes agrícolas
(Universidade Federal de São Carlos, 2026-06-25) Nepomuceno, Kaio Socorro Dias; Enes, Adilson Machado; http://lattes.cnpq.br/4212875715055352; https://orcid.org/0000-0002-7892-0400; Gazzola, Jonathan; http://lattes.cnpq.br/0159433721761670; https://orcid.org/0000-0002-3353-5832; http://lattes.cnpq.br/7958643433449250
Agricultural seeds are of great importance to Brazilian agribusiness, as well as to the country’s economy and food security. In this context, soybean (Glycine max) and corn (Zea mays) crops stand out. Therefore, ensuring the planting of viable seeds is essential for good productivity. The high quality of the seeds used directly contributes to good production; thus, the methods used to evaluate seed viability represent a crucial step for the success of agribusiness in Brazil and for ensuring that germination quality is guaranteed for producers. In this regard, there are tests aimed at verifying the germinative viability of seeds, such as the standard germination test and the tetrazolium test. However, these tests can be destructive and are performed using samples, which may increase the imprecision of the results. Thus, a method for analyzing germination quality that is non-destructive, rapid, and capable of analyzing seeds individually is desirable. This undergraduate thesis aimed to analyze the BioSpeckle Laser technique, whose desired characteristics mentioned above may be achieved. This technique uses a laser that scatters or transmits a beam of light. The reflection of the laser light on the plant tissue was collected by a CCD camera and stored for processing, which was performed using a specific algorithm. Quantitative data were obtained through the “Moment of Inertia” (MI) determination technique for image processing, as it makes it possible to analyze the biological activity of the material through the determination of the MI index and to identif abnormalities in cell functioning, thus verifying the viability and quality of a seed. The test specimens consisted of soybean and corn seeds that were stored under ideal and non-ideal conditions, causing variations in germination quality among the seeds. The results obtained were analyzed using graphs and statistical tests, such as analysis of variance (ANOVA). As a result, it was concluded that the differentiation in the seed storage method generated significant differences for the study, and the BioSpeckle Laser technique proved capable of identifying differences in the germinative potential of soybean and corn seeds.
Prospecção e caracterização de microrganismos intestinais do coleóptero Sphenophorus levis e suas enzimas com potencial para biodegradação de poliestireno
(Universidade Federal de São Carlos, 2026-07-17) Souza, Eduardo Pereira de; Silva, Flávio Henrique da; http://lattes.cnpq.br/1757309852446263; https://orcid.org/0000-0003-3329-4597; http://lattes.cnpq.br/0850771035889805; https://orcid.org/0000-0002-2013-0115; Silva, Flávio Henrique da; Fuentes, Andrea Soares da Costa; Ferro, Milene; Silva, Adilson José da; Moura, Daniel Scherer de; http://lattes.cnpq.br/1757309852446263; http://lattes.cnpq.br/2426157257540389; http://lattes.cnpq.br/3447469350644179; http://lattes.cnpq.br/9970111751569210; http://lattes.cnpq.br/0264232179982467
Polystyrene (PS) is a polymer with versatile physical and chemical properties and a low production cost, used for various purposes. Its growing demand, combined with poor waste management, leads to accumulation in the environment, triggering social and ecosystem problems. This issue is exacerbated because PS is a recalcitrant polymer due to its carbon–carbon (C–C) main chain, which makes its biodegradation in nature difficult. Studies have investigated strategies for the biodegradation of this polymer. It has been found that larvae of certain insects are capable of using PS as a carbon source, a phenomenon correlated with their gut microbiota. For this reason, the larva of Sphenophorus levis, previously observed ingesting expanded polystyrene (EPS), was used to prospect microorganisms and key genes involved in the material’s biodegradation process. The larvae were fed a diet restricted to EPS, and their intestinal microbial diversity was compared with that of larvae fed an artificial diet. It was observed that diversity decreased and the presence of its obligatory endosymbiont became more pronounced. The intestinal contents of the larvae were subjected to enrichment in a mineral medium, whose only carbon source was PS films. Five bacterial strains were isolated from the following genera: Bacillus, Lysinibacillus, Paenibacillus, Cytobacillus, and Raoultella. These were cultivated for 60 days on solid medium in contact with PS films. SEM analysis revealed cavities, cracks, and fissures in the films, and surface atom mapping indicated oxygen accumulation. FT-IR analyses indicated that only Paenibacillus sp. led to the formation of characteristic oxidation functional groups. Gel permeation chromatography indicated that the same strain was able to alter the polymer’s molar mass. To elucidate which mechanisms might be involved in this process, the entire genomes of two strains (Bacillus cereus and Paenibacillus lautus) were sequenced on the Illumina NextSeq 2000. Annotation identified proteins such as multicopper oxidases, ring-cleaving dioxygenases, cytochromes P450 (CYP), and glutathione peroxidases (GPx). CYP102 from P. lautus and the GPxs from both species were cloned and expressed in Escherichia coli. Both GPxs have thioredoxin peroxidase activity. The results demonstrate the potential of the intestinal microbiota of S. levis as a source of microorganisms and enzymes for PS biodegradation.
A teologia apofático-política de Thomas Hobbes
(Universidade Federal de São Carlos, 2026-07-03) Santana, Luiz Felipe Sousa; Hirata, Celi; http://lattes.cnpq.br/6347404660282248; https://orcid.org/0000-0003-0488-0677; http://lattes.cnpq.br/7022655532430217; https://orcid.org/0000-0002-1469-0183; Limongi, Maria Isabel; Nakayama, Patricia; Brondani, Clovis; Kontic, Sacha; http://lattes.cnpq.br/0001885194916158; http://lattes.cnpq.br/2185506817033759; http://lattes.cnpq.br/8140295673335754; http://lattes.cnpq.br/5253901262942631; https://orcid.org/0000-0001-8110-5055; https://orcid.org/0000-0003-2022-8662; https://orcid.org/0009-0004-0425-1453; https://orcid.org/0000-0002-6844-3663
This research seeks to understand how Thomas Hobbes's theological conceptions impact his political philosophy, highlighting the negative character of his statements about God and religious phenomena. His claims regarding divine incomprehensibility are present in his investigation of biblical revelation and the formation of religious dogmas, both of which are permeated by the dynamics of power — a key element in his anthropology. The purpose of this study is to examine how this apophatic position regarding the theological field as a whole determines the nature of sovereign right, as well as the role it plays in the secularization of political philosophy.