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Direito à água: contribuições para o acesso mais justo, equitativo e democrático à água
(Universidade Federal de São Carlos, 2025-03-31)
Moraes, Tatiana Vieira de
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Oliveira, Celso Maran de
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https://lattes.cnpq.br/9911833172043700
;
https://orcid.org/0000-0002-6442-3614
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https://lattes.cnpq.br/3999527499047171
Water in quantity and quality is an essential human right, but a large portion of the population still does not have access to this right. SDG 6 sets the goal of universal and equitable access to water for all people by 2030 and, based on the hypothesis that the current Brazilian water management system does not sufficiently guarantee access to the right to water in an equitable and fair manner, this study aims to identify, based on case studies of water conflicts, various possibilities and potential actions, measures or principles with a view to contributing to fairer, more equitable and democratic access to the right to water. To this end, methodological pluralism was adopted, with each chapter addressing a set of specific methods and procedures. The study is presented in three parts: the first, more theoretical, proposes a literature review. At this point, the right to access water as an essential human right is discussed, pointing out the possibility of considering water as a fundamental right in Brazil, even without express constitutional provision. It also analyzes the Brazilian National Water Resources Policy and criticizes the conventional model of water resources management adopted in Brazil, especially its limitations in terms of participation and equity. This is followed by a discussion of effective water governance, highlighting the importance of a governance system that strengthens the participation of society. This part of the study concludes with theoretical clarifications on the concept of water equity, presenting definitions and basic elements, as well as differentiating equity from water justice. The second part examines case studies of water problems/conflicts. Adopting a narrow geographical approach, a survey was carried out of cases of international and national water conflicts in the literature; in the state of São Paulo through Civil Inquiries by the Public Prosecutor’s Office of São Paulo (MPSP); and a local case in the municipality of São Carlos/SP. The results of this part of the study were the mapping of water conflicts based on the cases examined and the potential of the measures and solutions suggested and/or applied to resolve or mitigate the conflicts. The third part of the study is propositional, presenting contributions to more equitable and democratic access to the right to water and interconnecting the first two parts. The analyses of the previous parts of the study demonstrate the existence of various inequalities in access to water and the inadequacy of the conventional water management system to sufficiently guarantee fair, democratic and equitable access to the right to water. As a result, contributory proposals were generated aimed at advancing the transition from the current water management format to a more effective system of ‘good water governance’ that promotes democratic, equitable and fair access to the right to water.
Fusão em leito de pó a laser de aço ferramenta A2: efeito de parâmetros de processo, tratamentos térmicos e adição de Cr₃C₂
(Universidade Federal de São Carlos, 2025-03-31)
Bianchini, Bruno
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Gargarella, Piter
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https://lattes.cnpq.br/4641435644243916
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https://orcid.org/0000-0003-4445-5819
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https://lattes.cnpq.br/8443988120967281
Tool steels have strict requirements for composition, processing and mechanical properties, and are utilized in fabrication of molds or tools employed in the processing of other materials. In many cases, they are expensive and of difficult machinability, which opens up the possibility for alternative processing routes such as additive manufacturing (AM) by Laser Powder Bed Fusion (L-PBF), which allows fabrication of parts with complex sections, such as internal cooling channels, without additional processing cost and with minimal need for post-processing, due to its great dimensional accuracy. However, the severe conditions to which the L-PBF process submits materials induce the formation of a highly refined microstructure, and possibly defects. This work studies the possibility of manufacturing AISI A2 tool steel by L-PBF, considering the effect of process parameters and post-processing in its microstructure and properties, and the modification of this material for defect mitigation. Results showed that, despite it being possible to determine a processing window for minimal porosity, the material composition and the severe processing conditions cause the formation of cracks, mostly during solidification. The as-built microstructure is, similarly to other tool steels manufactured by L-PBF, composed of martensite cells surrounded by retained austenite, while the formation of primary carbides is suppressed. After heat treatment, the formation of secondary carbides was found to be also in low quantity, showing that temperings without prior austenitization would need higher temperatures or longer times to cause significant effects on the microstructure and mechanical properties. Finally, it was discovered that the addition of Cr3C2 chromium carbide by mechanical mixture, at a fraction of 5%, was capable of mitigating defect formation by altering the alloy composition, when manufactured by L-PBF.
Feijão guandu para uso alimentar: composição química, funcionalidade e aspectos nutricionais
(Universidade Federal de São Carlos, 2025-03-31)
Tozo, Marcelo Larsen de Lima
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Rita de Araujo Nogueira, Ana
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https://lattes.cnpq.br/7034773971317045
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https://orcid.org/0000-0003-3648-2956
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https://lattes.cnpq.br/6205481423806854
This dissertation aims to develop and apply analytical procedures to evaluate the total levels, bioaccessibility, and bioavailability of essential elements and total proteins in two pigeon pea (Cajanus cajan (L.) Millsp) varieties previously selected for human consumption. Raw and cooked samples were evaluated at different stages of maturation, as well as commercial varieties of common beans (carioca and black). Bioaccessibility and bioavailability were obtained after in vitro gastrointestinal digestion simulations and bioassays with Caco-2 cells. For proteins, the total fraction and the bioaccessible fraction were quantified by combustion (Dumas), and free amino acids by high-performance liquid chromatography (HPLC). The macro and micronutrients evaluated, Ca, Mg, P, Cu, Fe, and Zn, were determined by inductively coupled plasma optical emission spectrometry and mass spectrometry (ICP OES and ICP-MS), after microwave-assisted decomposition using diluted acid (7.0 mol L-1), both for total contents and for bioaccessible and bioavailable fractions. The bioaccessibility of elements varied from 0.8 to 19% for Ca and from 48 to 67% for Cu. Bioaccessibility of Ca, Fe, Mg, and Zn decreased with bean maturation. Finally, an in vitro intestinal simulation with Caco-2 cells, aimed at estimating nutrient bioavailability, faced issues with the integrity of the cell monolayer, making it impossible to estimate bioavailability values. However, the results obtained suggest the direction to be followed for improving this experiment and obtaining reliable results. Regarding crude protein content, pigeon pea samples were close to 20%. For amino acids, amounts ≥ 1% of glutamic acid, aspartic acid, and leucine were found. For the mature grain, lysine and phenylalanine were present in amounts ≥ 1%, compared to the green grain. However, in the mature grain, the amounts of glycine, histidine, threonine, alanine, and tyrosine were low (≤ 0.4%), and no methionine, cystine, or taurine were detected in either grain. The protein bioaccessibility varied between 16.4% and 19.4%. There was an increase in the total protein content with the maturation of the beans, while the bioaccessible percentage remained unchanged. For the recommended daily intake (RDI), the consumption of 100 g of cooked food suggests that the pigeon pea may be an alternative source of nutrients, highlighting Mg and P, although its contribution is lower compared to the commercial varieties of carioca and black beans. Additionally, all the beans studied show potential for protein supplementation, ranging from 32.8 – 38.8% of the RDI, reinforcing the importance of these legumes and others in human nutrition.This study is significant from a nutritional perspective, providing unprecedented data on the nutritional aspects of two varieties of pigeon peas and the bioaccessibility of essential elements, indicating their use as a consumption alternative.
Modelagem multiescala e validação experimental da dinâmica interfacial em sistemas de eletrólise da água: explorando fenômenos locais inerentes das reações eletroquímicas
(Universidade Federal de São Carlos, 2025-03-31)
Leite, Gabriel Wosiak
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Souza, Ernesto Chaves Pereira de
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https://lattes.cnpq.br/1505400360366643
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https://orcid.org/0000-0003-1058-302X
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https://lattes.cnpq.br/8033550667466489
This thesis addresses the efficiency challenges in hydrogen production via water electrolysis, focusing on the coupled effects of gas bubble evolution and interfacial pH variations during alkaline electrolysis. Multiscale computational models were developed, combining the Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) to simulate bubble dynamics and interfacial pH distribution, with experimental validation using filming techniques and chronopotentiometric analysis to explore energy consumption during electrolysis. The results showed that pulsed-current operation can mitigate local pH variations; however, maintaining stable pH conditions under high current densities remains a challenge. Additionally, an asymmetric electrolysis cell configuration was proposed and validated, demonstrating a reduction in local pH gradients and up to a 17% improvement in electrolysis efficiency. This work opens new perspectives for developing more efficient electrolyzers, contributing to sustainable and economically viable hydrogen production.
Como a alfabetização científica se desenvolve no contexto da educação básica: um olhar sobre a prática docente
(Universidade Federal de São Carlos, 2025-03-31)
Stranghetti, Natalia
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Marques, Clelia Mara de Paula
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https://lattes.cnpq.br/0451284088402660
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Venâncio, Tiago
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https://lattes.cnpq.br/4438399441102990
This study aimed to analyze the presence and development of Scientific Literacy (SC) in Basic Education, highlighting its relevance as an essential tool for understanding and applying scientific knowledge in everyday life and in the modern world. To this end, Chemistry classes were monitored in two state schools, seeking to identify the presence of SC in basic education. In addition, the teachers of these classes were interviewed, allowing a qualitative analysis based on the principles of Bardin's Content Analysis. Initially, SC indicators observed during classes were collected, while categories were created for essential aspects that did not appear, but are fundamental for the development of SC in education. In order to deepen the investigation, interviews were conducted with other teachers from the state network to understand their perceptions about SC. The research also included the analysis of legislation and documents guiding education in Brazil, such as the National Common Curricular Base (BNCC) and the Law of Guidelines and Bases of National Education, in order to verify how SC is addressed in curricula and pedagogical guidelines. The results indicated that CA is present in Basic Education, but there is a vast potential that has not yet been explored, since several essential parameters were not identified in the observed teaching practice. The study suggests that CA could be significantly more stimulated if there were greater awareness and guidance among education professionals about its importance. In addition to the lack of specific knowledge, it was found that the limited time allocated to the study of teaching tools and methods compromises the development of pedagogical practices that facilitate the learning and understanding of scientific content.
Influência da dopagem de Fe/Co sobre as propriedades dielétricas no sistema Bi3.25Nd0.75Ti3O12
(Universidade Federal de São Carlos, 2025-04-01)
Lozano, Rafael
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Zabotto, Fabio Luis
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https://lattes.cnpq.br/8828635263888498
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https://orcid.org/0000-0003-2868-6828
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https://lattes.cnpq.br/5602149711574787
With the trends in environmental protection, there is a growing interest and demand in the development of lead-free ferroelectric materials to replace lead-based materials with properties suitable for various technological applications. In this context, bismuth titanate (Bi4Ti3012 - BiT) is a material with a structure of the Aurivillius family, or bismuth layers, with high potential for applications in devices and other technological apparatuses because it presents ferroic and also multiferroic properties due to its compositional manipulation and that mimic some characteristics presented by the dominant material in these applications, lead zirconate titanate (PbZr1−xTixO3 - PZT). In this case, it is possible to tune both the dielectric and ferroelectric properties and add multiferroic and/or photovoltaic properties to the BiT system through doping with chemical elements of interest. In this work, the material Bi3.25Nd0.75Ti(3−x)(Co1/2,Fe1/2)xO12 was prepared using the conventional sintering technique, which is a bismuth titanate modified with neodymium (Nd) in the Bi A site and with iron (Fe) and cobalt (Co) ions in the Ti B site. The effects of the Nd dopant confer to the BIT system the improvement of the electrical polarization, while the co-doping with Fe/Co is motivated by the search for control of the crystal structure and properties, mainly inducing multiferroic properties. Furthermore, the presence of Fe and Co in the bismuth titanate matrix can result in unexplored phenomena, such as additional phase transitions and improvement of the magnetic behavior induced by modifications. Thus, this work proposes to explore the effects of co-doping of cobalt and iron on the dielectric, pyroelectric and ferroelectric properties of the system Bi3.25Nd0.75Ti(3−x)(Co1/2,Fe1/2)xO12, with 0 ≤ x ≤ 0.4 (abbreviated as BNdTFC-x). For this purpose, impedance spectroscopy techniques and pyroelectric properties were explored in samples with different Fe/Co doping compositions, subjected to temperatures between 15 K and 980 K. The analysis allowed to identify ferroelectric-paraelectric phase transitions, as well as to investigate the influence of co-doping on the electrical and dielectric properties of the material. The results demonstrated that the introduction of Fe and Co shifts the transition temperature to higher values, but also influences the electrical conduction mechanisms, impacting the dielectric loss under certain conditions. Furthermore, the variation of critical temperatures with doping suggests relevant structural and electronic modifications, contributing to a better understanding of the ferroelectric behavior of the system. These observations make the material an interesting candidate for applications in electronic devices operating at high temperatures.
Escreventes técnico judiciários e a construção profissional de sua atuação em um foro de violência doméstica e familiar de São Paulo
(Universidade Federal de São Carlos, 2025-04-01)
Kahwage, Tharuell Lima
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Bonelli, Maria da Glória
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https://lattes.cnpq.br/1739441747281321
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https://orcid.org/0000-0003-3877-9825
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https://lattes.cnpq.br/8934697439653323
Judicial clerks are a group composed mostly of white women, who take up such positions more frequently than men, according to data from the National Council of Justice. They are responsible for practices essential to the functioning of the justice system, performing administrative and routine activities, such as filing cases, serving the public, and drafting legal documents. Despite the centrality of their role and the functions they perform, studies on this group are still incipient, especially when compared to production around the judiciary, an activity of greater preference and notoriety compared to civil servants, who tend to accumulate activities of less autonomy. Based on this scenario, the objective of this research is to understand how the position of judicial technical clerk is constructed, particularly those who work in a court of domestic and family violence against women in the state of São Paulo. I seek to analyze, through narratives produced by interactions of disputes and cooperation between themselves and other actors, what meanings they elaborate on the activities they perform, as well as how processes of gendering and racialization occur in this dynamic. This is an ethnography recorded through a field diary combined with semi-structured interviews, the data from which were subjected to content analysis. The data obtained reveal that the construction of the position is a dynamic process, shaped by social interactions of dispute and cooperation, as well as by the constant negotiation of the meanings present in their narratives.
(Des)estímulo à participação popular: inefetividade das ações populares e das ações civis públicas ajuizadas por associações na seara ambiental
(Universidade Federal de São Carlos, 2025-04-01)
Ribeiro, Elen Pessoa de Queiroz
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Oliveira, Celso Maran de
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Amarante Junior, Ozelito Possidonio de
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https://lattes.cnpq.br/1314612121213589
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https://lattes.cnpq.br/9911833172043700
As ações coletivas são importantes instrumentos que podem ser utilizados na tutela do meio ambiente. Além de conferirem segurança jurídica, estimulam a participação popular e fortalecem o exercício da democracia. Todavia, a pandemia que se iniciou no ano de 2020 acarretou uma crise humanitária que assolou o globo e marcou setores econômicos, políticos e sociais, além de afetar as atividades jurisdicionais. [...] Assim, foi possível observar que as Ações Populares são instrumentos subutilizados, bem como as Ações Civis Públicas, por parte das associações, e estão mais sujeitas a não obterem êxito na tutela do objeto pretendido.
Reciclagem de biopolimeros e a formação de substancias não intencionalmente adicionadas: uma abordagem para contato com alimento
(Universidade Federal de São Carlos, 2025-04-02)
Paiva, Robert da Silva
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Nerín de La Puerta, Maria Cristina
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https://orcid.org/0000-0003-2685-5739
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Cruz, Sandra Andrea
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https://lattes.cnpq.br/9632409046763256
The increasing demand for sustainable solutions in the packaging industry has driven the adoption of biodegradable polymers such as poly (lactic acid) (PLA). However, the efficient recycling of post-consumer PLA remains a challenge due to contamination from food residues, cleaning products, automotive substances, and improper disposal. This study addresses the optimization of the PLA recycling process, focusing on the effects of washing, the formation of recycled material for food contact applications. The influence of washing parameters on PLA degradation was evaluated using the Design of Experiments (DoE) methodology. Variables such as sodium hydroxide concentration, temperature, washing time, and surfactant concentration were analyzed. Rheological studies, based on the Cox-Merz rule, revealed that material degradation can be minimized through precise adjustment to these parameters. Specifically, surfactant concentration exhibited a less aggressive effect, even when combined with high temperatures and prolonged times. Conversely, washing time was identified as the most critical factor, particularly when paired with high temperature and sodium hydroxide concentration. The results suggest that adapting washing parameters according to the contamination level of the precursor material enables a more efficient and sustainable recycling process. In parallel, the study examined the formation of Non-Intentionally Added Substances (NIAS) and the presence of contaminants during the recycling process, a critical aspect for meeting international food standards. PLA samples were intentionally contaminated in the laboratory, washed, and mechanically recycled under simulated industrial conditions. Using Headspace Solid-Phase Microextraction with Gas-chromatography coupled Mass spectrometry (HS-SPME-GC-MS) and olfactometric analysis (HS-SPME-GC-O-MS) methods, 34 volatiles compounds were identified, including NIAS such as benzaldehyde, benzyl alcohol, and dimethyl-1,4-dioxane-1,5-dione. Additionally, 14 odor-active compounds were detected and classified into four main groups: toasted, floral, green, and chemical. The study demonstrated a correlation between the recycling stages and NIAS formation, highlighting the importance of rigorous control to ensure compliance with safety standards. The efficiency of the recycling process in contaminant removal was also evaluated following FDA guidelines. PLA samples were contaminated with a standard cocktail composed of benzophenone, tetracosane, heptane, chloroform, and toluene. After washing and mechanical recycling steps, migration tests were conducted using two food simulants under various time and temperature conditions. Analysis using SPME-GC-MS and direct injection (DI-GC-MS) showed a significant reduction in contaminants after the complete recycling cycle, with decreases ranging from 73% to 80% for substances such as tetracosane, heptane, and toluene. In comparison, washing or mechanical recycling alone showed lower removal efficiency. Factors such as the molecular volume of contaminants, type of simulant, temperature, and the interactions between PLA and contaminants directly influenced the results. Theoretical calculations of molecular interactions supported these observations, proving a detailed understanding of the underlying mechanisms. Another focus of the study was mitigating molar mass loss and oligomer formation during the recycling cycle, common challenges for materials intended for direct food contact. To address these issues, carbodiimide (CDI) was added, using co-rotating twin-screw extruders. Results showed that CDI promoted an increase in PLA molar mass and reduced oligomer formation. Moisture played a key role, as carbodiimide reacts both with water molecules, preventing hydrolytic degradation, and with PLA chains, leading to increased molar mass. Oligomer migration tests were performed using three food simulants (ethanol 10%, acetic acid 3%, and ethanol 95%) and analyzed through ultra-high performance liquid chromatography coupled with mass spectrometry (UPLC-QTOF-MSE). Sixteen types of oligomers were identified, with linear oligomers detected in all simulants and cyclic oligomers predominantly found in the ethanol 95% simulant. Theoretical calculations of electronic structure confirmed the observed interaction and migration mechanisms, offering insights into the stability and behavior of the recycled material. The addition of CDI significantly reduced the total oligomer concentration, improving the physicochemical properties of PLA and ensuring its suitability for food contact applications. In conclusion, the study demonstrated that optimizing washing parameters, controlling contaminants and NIAS, and using additives such as carbodiimide are effective strategies for improving PLA recycling. These approaches not only ensure the quality and safety of recycled material but also align with circular economy principles, contributing to the reduction of the environmental impact associated with biodegradable plastics.
Aplicação de amido termoplástico com nanopartículas de quitosana para liberação de nutrientes NPK
(Universidade Federal de São Carlos, 2025-04-02)
Franco, Rafael Augusto
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Ferreira, Marystela
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https://lattes.cnpq.br/4714185516263478
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https://orcid.org/0000-0002-9459-8167
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https://lattes.cnpq.br/7506955060907326
For this study, thermoplastic starch (TPS) films containing NPK nutrients reinforced with chitosan nanoparticles were produced and characterized, aiming at the adsorption of nutrients to them. A device for slow release of NPK nutrientes as prepared. Starch was chosen as the substrate, because it is a biodegradable polysaccharide and extremely abundant in nature. Chitosan has carrier properties on a nanometric scale, due to the increase in its contact surface and the presence of electrostatic groups in its composition. Nanochitosan was obtained through its ionic gelation, in combination with the radical polymerization of methacrylic acid. Using the dynamic light scattering (DLS) technique, an average size of 130.41 ± 1.45 nm and a zeta potential of 24.7 ± 0.7 mV were observed. Then, NPK nutrients were incorporated into the nanochitosan. The particles obtained were analyzed by transmission electron microscopy (TEM), before and after the incorporation of NPK nutrients. These were added to the preparation of thermoplastic starch (TPS) films by wet casting. The thicknesses of the films with and without nanochitosan did not show significant differences. The films with nanochitosan are more resistant to solubilization compared to films containing only NPK. The films were characterized by infrared spectroscopy (FT-IR) and contact angle analysis. The bands that appear with greater absorption intensity in the films refer to the C-O bonds (1600 cm-1) and the C-O-C bonds (between 750 cm-1 and 1000 cm-1) present in the cyclic rings of the starch structure. The contact angle was greater in the film with nanochitosan, indicating that it is capable of making the film less hydrophilic. Its release was studied in the laboratory, through the analysis of percolated samples of simulated soil in the UV-vis spectrophotometer and in situ, through application in the rooting of vegetatively propagated seedlings of the Trema Micrantha species. The percolated samples with the lowest presence of ions were those obtained from the simulated soil containing the films with nanoparticles. Better rooting was observed among the seedlings with nanoparticles. Therefore, the TPS films containing nanochitosan presented better physical properties and beneficial effect on the rooting of vegetatively propagated seedlings.
Desenvolvimento de metodologias verdes e sustentáveis para a obtenção de agentes quimioterápicos a partir de resíduos de processamento de manga (Mangifera indica L.)
(Universidade Federal de São Carlos, 2025-04-02)
Zanotti, Karine
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Forim, Moacir Rossi
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https://lattes.cnpq.br/1234565160573730
;
https://lattes.cnpq.br/7538221736303396
;
https://orcid.org/0000-0003-1121-8366
Brazilian agro-industrial production generates alarming amounts of waste. In recent years, mango production has grown significantly, with the state of São Paulo among the largest producers, discarding tons of waste annually. These residues are rich in high-value bioactive compounds, and studies have investigated their antitumor potential due to the presence of secondary metabolites. Given the projected increase in cancer cases, exploring mango waste as a source of new anticancer drugs is a promising approach. Practices aligned with sustainable development should be adopted, with emphasis on using Green and Sustainable Chemistry principles, promoting the creation of products and processes that prevent the generation and use of environmentally harmful substances. Concepts such as biorefinery and circular economy are applicable in this context, utilizing biomass as a raw material to obtain new products. This study aimed to develop green and sustainable analytical methods for obtaining a chemotherapeutic agent through the extraction of secondary metabolites from mango waste. Bioassay-guided experiments on tumor cell lines, combined with spectrometric analyses using test extracts and their fractions, allowed the annotation of the target analytes: gallic acid and methyl gallate. Using chemometric techniques, two extraction methods were evaluated and optimized: homogenization-assisted extraction and microwave-assisted extraction, employing only green solvents such as water and ethanol, and considering the influence of the variables in the extraction. The extracts were analyzed by liquid chromatography coupled with mass spectrometry. The analytes were quantified based on analytical curves, demonstrating selectivity, linearity (R² > 0.999), detection and quantification limits suitable for the linear range, as well as precision (< 2%), accuracy (> 96%), and recovery (> 94%). Among the evaluated variables, ethanol composition (40% v.v⁻¹) in water and the number of extractions (1×) were the most relevant for the optimized extract obtained by homogenization. For the optimized extract obtained by microwave-assisted extraction, ethanol composition (80% v.v⁻¹) in water and temperature (70°C) were the most critical factors. The antitumor properties of test extracts, optimized extracts, and analytical standards of gallic acid and methyl gallate were evaluated in lung and ovarian cancer cell lines, as well as in non-tumor lung cells. The optimized extracts presented lower IC50 values compared to the test extracts, demonstrating greater selectivity for tumor cells. The optimized extract obtained by microwave-assisted extraction was the most promising, with IC50 values of 6.09 and 0.21 μg.mL⁻¹ for lung and ovarian tumor cells, respectively. The optimized extracts showed IC50 values comparable to the drugs cisplatin and doxorubicin, with significantly higher selectivity for tumor cells. A comparison between the extracts and analytical standards revealed a strong synergistic interaction among the matrix compounds. Morphological and clonogenic assays demonstrated that the optimized extracts exhibit cytostatic and cytotoxic profiles, indicating cell death. The results highlight the potential for reusing mango waste to obtain antitumor agents using green analytical methodologies.
Métodos de controle de qualidade aplicados a produtos cosméticos baseados em nanotecnologia
(Universidade Federal de São Carlos, 2025-04-03)
João, Luana
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Pereira Filho, Edenir Rodrigues
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https://lattes.cnpq.br/3394181280355442
Driven by consumers who are increasingly concerned with physical appearance, the cosmetics market has grown significantly in Brazil and around the world in recent years. According to data from Euromonitor International, Brazil ranks third in the global market for cosmetics and personal care products. However, alongside the growth of this sector, the public has become increasingly demanding, seeking products that not only offer traditional functions such as hydration, cleansing, and exfoliation, but also provide personalized benefits and care tailored to individual needs. This includes products that help reduce sunspots, acne, oiliness, rosacea, and more. In order to meet these consumer demands, the cosmetics industry has been investing in the development of new technologies aimed at enhancing the performance of active ingredients. Among these innovations, nanotechnology has stood out. It enables the development of cosmetic-grade materials at the nanometric scale typically between 1 to 100 nanometers which, due to their size and characteristics such as charge and surface area, exhibit unique properties that enhance their effectiveness in cosmetic formulations. Because of their reduced size, nanostructured materials used in these products present an increased surface area, which directly impacts their chemical reactivity, as well as quantum effects that significantly modify their optical and magnetic properties, for example. As a result, the application of nanotechnology in beauty products not only enhances the activity of the actives but also improves their stability, release, and skin absorption, thereby increasing the product's overall efficacy. However, before reaching consumers, cosmetic and personal care products must undergo a series of quality control tests to ensure their safety and effectiveness. These include physicochemical, organoleptic, and analytical tests. In Brazil, ANVISA is the agency responsible for the regulation of cosmetics and personal care products. Meanwhile, the FDA and the European Union provide guidance on the safety of nanomaterials used in cosmetic formulations. Therefore, this undergraduate thesis aims to present the quality control methods for cosmetic products containing active ingredients at the nanometric scale.
Nanostructured TPS/PVA/CNC films for sustained copper oxide nanoparticle release: toward advanced transdermal dressing systems
(Universidade Federal de São Carlos, 2025-04-03)
Freitas, Amanda de Sousa Martinez de
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Rodrigues, Jéssica de Souza
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Municoy, Sofia
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Antezana, Pablo
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Desimone, Martín
The search for biodegradable alternatives to traditional dressings has driven the development of thermoplastic starch nanocomposite films (T) with polyvinyl alcohol (P) and cellulose nanocrystals (CNC). Films were prepared via the casting technique with varying PVA concentrations (10, 20, 30, and 40 % w/v) and CNC reinforcements (2.5, 5.0, and 10 % w/w). The synthesis and characterization of copper oxide nanoparticles (NPCuO) was also carried out. The best-performing films were further modified with NPCuO to study their controlled release. The final material developed (T/P/10CNC/NPCuO) was extensively characterized, with measurements of thickness, swelling capacity in PBS buffer, tensile test, contact angle measurements, thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR). In addition, solubility, water vapor permeation, NPCuO release by visible ultraviolet spectroscopy (UV–Vis) and the cytocompatibility of the developed films were studied. NPCuO characterization showed hexagonal morphologies, a zeta potential of –32 mV, a hydrodynamic diameter of 122 nm (PDI = 0.5). Mechanical tests revealed that adding 10 % CNC tripled the stress at rupture compared to unreinforced films. Contact angle measurements (62◦) confirmed hydrophilicity, a desirable property for dressings. The films showed good solubility in PBS, sustained release of nanoparticles for 8 h. Water vapor permeability increased from 0.9 to 1.75 g.mm􀀀 2.kPa􀀀 1.day􀀀 1 with CNC addition and to 1.88 g.mm􀀀 2.kPa􀀀 1. day􀀀 1 with NPCuO. NPCuO release was low but provided enhanced antioxidant activity: 76 % (24 h), 67 % (48h), 43 % (72 h), and 38 % (96 h), outperforming T/P/10CNC. These nanocomposites exhibit promising mechanical, permeability, and antioxidant properties, making them suitable candidates for transdermal dressings.
Proveniência de dados e metadados em repositórios de dados de pesquisa
(Universidade Federal de São Carlos, 2025-04-03)
Silva, Felipe Ivo da
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Baptista, Ana Alice Rodrigues Pereira
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https://orcid.org/0000-0003-3525-0619
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Arakaki, Felipe Augusto
;
https://lattes.cnpq.br/5324289839207169
Research data repositories are environments for storing, preserving, and sharing scientific data, and ensure accessibility and reuse of data. Provenance, which documents the origin, history, and transformations of data, is essential to ensure the tradition, reliability, and traceability of information. However, the lack of standardization and interoperability between the main metadata standards in these repositories can compromise the effectiveness of provenance. In this context, the central question of this research was: do the metadata standards used to describe data in research repositories ensure traceability and prevent information from becoming obsolete over time? The general objective of the study was to evaluate the adherence of provenance metadata, based on the PROV Family, to the main metadata standards used in research data repositories according to Re3data, such as Dublin Core, DataCite, and DDI. The research sought to identify how these standards can assist in identifying deficiency and traceability of information, proposing recommendations for their application. The methodology adopted was theoretical and exploratory, using a bibliographic survey in recognized databases, analysis of specialized literature and the Crosswalk method to map and compare metadata standards in relation to PROV-O. The analysis focused on the interoperability between the standards and the PROV Family, eventually identifying possible adaptations to improve semantic interoperability. The main results indicated that the developed standards have different degrees of interoperability with the PROV Family. Dublin Core presented the highest relative correspondence, while DataCite and DDI presented lower levels of interoperability. Despite the integration suggestions, limitations were specified that exclude adaptations to meet the semantic interoperability principles promoted by the W3C. In conclusion, the study reinforces the importance of provenance for the reliability and traceability of data in research data repositories, highlighting the need for interdisciplinary collaboration between Information Science and Computer Science to improve data management in digital environments. The research suggests the implementation of provenance metadata to promote data veracity and longevity.
De frente para a tela: as implicações do uso das plataformas digitais no contexto da pandemia da COVID-19 nas percepções dos professores da educação básica de Mato Grosso do Sul
(Universidade Federal de São Carlos, 2025-04-03)
Theodoro, Yasmine Braga
;
Lima, Jacob Carlos
;
https://lattes.cnpq.br/9244132532446607
;
https://orcid.org/0000-0001-6475-9575
;
https://lattes.cnpq.br/9200144368829130
The adoption of Emergency Remote Teaching (ERT) during the SARS-CoV-2 (Covid-19) pandemic forced educational systems to adapt their practices to ensure the continuity of activities remotely. In the state of Mato Grosso do Sul (MS), this adaptation involved a reorganization of teaching work in schools, with increased use of digital platforms and the adoption of technological services for education. This research seeks to understand the introduction and expansion of digital platforms in the State Education Network (REE) during the aforementioned health crisis and investigate the perceptions of teachers and administrators regarding this phenomenon, focusing on the intensification and precariousness of teaching work. The hypothesis was that the combination of the pandemic and increased use of digital platforms exacerbated teachers' precarious working conditions. Therefore, the aim was to understand the new forms of teaching work management through Complementary Pedagogical Activities (CPAs), associated with the use of Information and Communication Digital Technologies (ICDTs), and the phenomenon of platformization. Additionally, it sought to investigate Google's role in Basic Education and compare teachers' and administrators' perceptions of the use of its platforms during ERT, identifying whether changes in work organization persisted upon returning to face-to-face teaching. To achieve this, the research used a mixed methodology, combining the application of questionnaires with REE/MS teachers to obtain quantitative data on the use of digital platforms, with semi-structured interviews that further explored their perceptions on the subject. The results indicated that, although digital platforms were necessary tools for the continuity of teaching during the pandemic period, they also imposed an increased workload on teachers in Mato Grosso do Sul and accentuated inequalities in access to technologies, contributing to the precarization of teaching work during ERT.
Investigação da indução de metabólitos em soja [Glycine max (L.) Merr.] frente à herbivoria por Spodoptera frugiperda (J. E. Smith) (lepidoptera: noctuidae)
(Universidade Federal de São Carlos, 2025-04-04)
Costa, Josicleia Oliveira
;
Wouters, Felipe Christoff
;
https://lattes.cnpq.br/4392349445398645
;
https://lattes.cnpq.br/9469985968777626
Soybean (Glycine max (L.) Merrill) is a crop of great economic and nutritional importance, widely cultivated in Brazil and around the world. However, its cultivation faces significant challenges, with pest attacks being one of the main threats to productivity. Among these pests, the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), stands out due to its high adaptability and resistance to traditional control methods, such as the use of insecticides. This insect is capable of attacking plants from the early developmental stages to the reproductive phases, compromising both yield and crop quality. The intensive use of insecticides has had negative impacts on the agroecosystem, which drives the search for more sustainable strategies, such as studying the natural resistance of plants and the metabolites involved in this interaction. In this study, the induction of metabolites in young and old soybean leaves at different vegetative stages (VC, V2, and V5) subjected to herbivory by S. frugiperda was investigated. Through untargeted metabolomic analysis, performed by UHPLC-Q-TOF-MS/MS, it was possible to identify and annotate a variety of primary and secondary metabolites, with a focus on fatty acids, phenolic acids, and terpenoids. The results showed that the VC and V2 stages were the most responsive to stress caused by herbivory, exhibiting greater metabolic changes. In contrast, the V5 stage showed less metabolic induction, with compounds exclusively related to primary metabolism. At the same time, the effect of induced resistance in the different vegetative stages on the biological development of S. frugiperda was assessed. For this, the plants were subjected to previous herbivory experiments, and in bioassays, the caterpillars were fed with previously induced leaves. The parameters analyzed included larval, pupal, and adult weights, as well as leaf consumption. The results revealed that the VC and V2 stages had a significant impact on the development of S. frugiperda. At the VC stage, there was a substantial reduction in pupal and adult weights, while at the V2 stage, there was a significant decrease in larval and adult mass. On the other hand, the V5 stage was more susceptible, allowing more favorable caterpillar development, without significant changes in the biological parameters evaluated. These findings reinforce that leaf age and plant development stage directly influence both the magnitude of the metabolic induction response and the development of S. frugiperda, highlighting the importance of considering these variables in the sustainable management of agricultural pests.
Ultrassom como pré-tratamento na obtenção do óleo essencial de Melaleuca alternifolia (Maiden e Betche) Cheel.
(Universidade Federal de São Carlos, 2025-04-04)
Vaz, Adriel Rodrigues
;
Freitas, Roberta Ranielle Matos de
;
https://lattes.cnpq.br/4952749113890055
;
Pádua, Franciane Andrade de
;
https://lattes.cnpq.br/2945447364979913
The essential oil market has shown continuous growth in recent years, with a significant increase after the COVID-19 pandemic. In 2022, the global market reached USD 8.8 billion, with projections to reach USD 15.3 billion by 2027, driven by greater awareness of preventive health and a growing preference for natural alternatives. Among plants with potential for essential oil extraction, Melaleuca alternifolia (Tea Tree) stands out for its wide range of applications. However, in Brazil, research has focused primarily on the pharmacological properties of the species, with gaps in studies on the optimization of its cultivation and extraction. This study evaluated the application of ultrasound pretreatment as a strategy to enhance the yield of essential oil extraction from M. alternifolia, aligned with the sustainable principles of Green Chemistry. The effects of three operational parameters during the pretreatment were investigated: sonication time (0, 10, 20, 30, and 40 minutes), ultrasonic bath temperature (25 °C, 40 °C, and 60 °C), and liquid-to-solid ratio (LSR) (10, 15, and 20 mL g⁻¹). The extractions following the pretreatment were performed by hydrodistillation using a Clevenger apparatus. Parameter optimization was conducted using Linear Mixed Models (LMM). The chemical composition of the extracted oils was evaluated using Fourier Transform Infrared (FTIR) spectroscopy and compared to a commercial sample to identify potential structural alterations due to the ultrasound pretreatment. The results demonstrated that increasing the ultrasonic bath temperature during the pretreatment reduced the extraction yield, while prolonging sonication time increased the yield, though in a nonlinear fashion. For the LSR, moderate proportions ensuring full immersion of the material, such as 15 mL g⁻¹, showed the best performance. Spectroscopic analysis indicated that the ultrasound pretreatment did not cause significant changes in the chemical composition of the essential oil. It is concluded that the use of ultrasound as a pretreatment is an efficient approach to optimize the extraction of essential oil from M. alternifolia, enabling an increase of up to 48% in yield compared to conventional hydrodistillation without ultrasound pretreatment.
O que vem depois das águas: entre arquivos da exceção e libertação da terra no Submédio São Francisco
(Universidade Federal de São Carlos, 2025-04-04)
Bezerra, Sabrina Maria Gonçalves Luz Barros
;
Marques, Adalton Jose
;
https://lattes.cnpq.br/4640452160891026
;
Villela, Jorge Luiz Mattar
;
https://lattes.cnpq.br/8301325600502054
This dissertation is the result of research conducted among archives that were opened due to the same problem: the conditions and effects of the appreciation of Caatinga lands and their relationship with water in the Submédio São Francisco Valley (SMFS). The investigation led me to the documents of three entities, in this order: i) the Superintendence for the Development of the Northeast (Sudene); ii) the Dom José Rodrigues Collection, the former library of the Diocese of Juazeiro-BA, designed by Bishop Dom José Rodrigues (1975-2003); and iii) the Archive of the Pastoral Land Commission of Juazeiro (CPT). Understood as distinct forms of constitution and visibility of formulations, the documentary and archival heterogeneity present here reflects forces that emerged and acted to transform or resist the changes imposed by development projects in the Submédio. Thus, a documentary fabric was constructed capable of deepening the relationship between the Public Irrigation Policies of the 1980s and the construction of the Sobradinho Dam in Bahia during the 1970s — whether through planning statements or through discourses of reaction and resistance. This documentary fabric constitutes the very essence of this research. That is, a documentation constructed under a relationship of forces. On the one hand, Sudene represents efforts to transform the São Francisco caatinga into an example of modernity and development, seeking to transform the exception of development into the rule; on the other, the CPT and the Diocese of Juazeiro bring together efforts aimed at the liberation of human beings and their lands. Thus, these archives can be understood, respectively, as archives of exception and archives of liberation — theoretical-methodological strategies that allow us to examine authors, testimonies, gaps and other elements, some of which have been eclipsed, related to the problem of water and land in the São Francisco.
Reflexões sobre a educação de surdos e o ensino de Libras-L1 a partir do Currículo da Cidade de São Paulo
(Universidade Federal de São Carlos, 2025-04-04)
Cruz, Márcia
;
Yokota, Rosa
;
https://lattes.cnpq.br/9230517686993400
;
https://orcid.org/0000-0002-1672-1430
;
https://lattes.cnpq.br/7794191148086276
Deaf education is a recurrent subject in this century and has, as its effect, the consolidation of bilingual approach as being the most adequate conception for the students´ teaching and learning. The bilingual process involving Libras (Brazilian Sign Languange), a visual-spacial language, and Portuguese, an oral-auditory one, is only taken into consideration in the written mode. It is understood that, for that process to occur in a satisfactory way, a solid linguistic basis in Libras, considered the native language, is necessary. This qualitative documental essay aims to reflect on the teaching of the deaf, dissecting the teaching of Libras as first language, with the goal of understanding its insertion in the school programme. We chose, as the source for the analysis, the document entitled Currículo da cidade: Educação Especial: Língua Brasileira de Sinais (City curriculom : Special Educationa: Brazilian Sign Language) of São Paulo city. The choice was due to it being a pioneer in the federal level. We intend to investigate and reflect about deaf education, acquisition and learning of the sign language by the deaf and the conception of a school programme, in order to understand the Libras Programme's contribution to the education of the deaf aiming to better understand in which way the referred conceptionsreveal themselves in the Currículo da Cidade: Educação Especial: Língua Brasileira de Sinais of São Paulo city.
Imagens de uma primeira-dama: Darcy Vargas no Cine Jornal Brasileiro
(Universidade Federal de São Carlos, 2025-04-04)
Siqueira, Sofia Figueira de
;
Sá Neto, Arthur Autran Franco de
;
https://lattes.cnpq.br/5055550097454248
;
https://orcid.org/0000-0003-4455-8105
;
https://lattes.cnpq.br/4252091251515961
This thesis analyzes the construction of Darcy Vargas’s image in the Cine Jornal Brasileiro during the Estado Novo (1937–1945), investigating the cinematic representation of this historical figure, with an emphasis on her role in social assistance. The research examines how Darcy Vargas’s image was associated with family, charity, and the Catholic Church, reinforcing the legitimacy of Getúlio Vargas’s government. Produced by the Departamento de Imprensa e Propaganda (DIP), the newsreels played a central role in disseminating the regime’s ideology, portraying the First Lady as a mediator between the State and the most vulnerable populations. Darcy Vargas’s actions, linked to institutions such as the Casa do Pequeno Jornaleiro and the Legião Brasileira de Assistência (LBA), strengthened the official government discourse as a protector of the people and a promoter of social harmony. The research adopts an approach that combines film analysis, the study of documentary sources, and a literature review to understand the role of this First Lady in Brazilian politics and the use of cinema in constructing official narratives. This study contributes to the debate on the relationship between gender, power, and communication, highlighting how Darcy Vargas’s image was shaped to serve the government’s interests and consolidate Getúlio Vargas’s authority in society.