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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
;
https://orcid.org/0000-0003-2685-5739
;
Cruz, Sandra Andrea
;
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
;
https://orcid.org/0000-0002-9459-8167
;
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
;
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
;
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
;
Antezana, Pablo
;
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
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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
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Lima, Jacob Carlos
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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
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Wouters, Felipe Christoff
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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
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Freitas, Roberta Ranielle Matos de
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https://lattes.cnpq.br/4952749113890055
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Pádua, Franciane Andrade de
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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
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Marques, Adalton Jose
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https://lattes.cnpq.br/4640452160891026
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Villela, Jorge Luiz Mattar
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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
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Yokota, Rosa
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https://lattes.cnpq.br/9230517686993400
;
https://orcid.org/0000-0002-1672-1430
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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
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Sá Neto, Arthur Autran Franco de
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https://lattes.cnpq.br/5055550097454248
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https://orcid.org/0000-0003-4455-8105
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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.
Obtenção e caracterização de extratos de folhas de yacon por líquido pressurizado sob diferentes condições de solvente e de temperatura
(Universidade Federal de São Carlos, 2025-04-04)
Souza, Larissa Lóren de
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Aguiar, Ana Carolina de
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https://lattes.cnpq.br/6206317990010266
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Pimentel Filho, Natan de Jesus
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https://lattes.cnpq.br/9157232954010211
The use of plants for medicinal purposes has been recorded throughout history. With scientific advances, it has been possible to identify some beneficial effects of plants related to the bioactive compounds present in them. Phenolic compounds stand out as bioactive compounds with antioxidant and anti-inflammatory capacity and potential for preventing cardiovascular diseases, cancer, neurodegenerative diseases, diabetes, osteoporosis and slowing down ageing. Still little known, yacon (Smallanthus sonchifolius) has demonstrated the presence of various classes of phenolics in its leaves, which makes it a promising natural resource that can be associated with emerging extraction technologies to obtain extracts rich in phenolic compounds with potential antioxidant action. Pressurized Liquid Extraction (PLE) and Subcritical Water Extraction (SWE), which in the literature have been shown to be efficient in recovering phenolic compounds, were used to obtain extracts from dried yacon leaves. The solvents used were ethanol 25% (v/v), ethanol 50% (v/v), ethanol 75% (v/v), ethanol 100% and pure water, at temperatures of 60, 90 and 120 °C, with extra points for water at 110, 130 and 150 °C. Subsequently, the extracts were characterized in terms of overall yield, total phenolics using the Folin Ciocalteu method, identification and quantification of phenolic compounds by ultraperformance liquid chromatography with photodiode array detector (UPLC-PDA), antioxidant capacity using the oxygen radical absorbance capacity (ORAC) and ferric reduction capacity (FRAP) methods, protein content using the Bradford method, in vitro anti-inflammatory activity, antimicrobial activity, minimum inhibitory concentration assay and analysis of antiquorum sensing activity. In addition, a comparison was made between emerging and conventional extraction methods using the Soxhlet technique. The results showed that increasing the temperature, combined with alcohol fractions of up to 50%, provided higher yields, as well as greater recovery of phenolic compounds and antioxidant capacity. In the chromatographic analysis, the main phenolic compounds identified were caffeic acid, glucaric acid, quercetin-O-hexoside and kaempferol derivatives. Five extracts showed antiinflammatory activity. The antimicrobial activity was evaluated against Lactococcus lactis ATCC 19435 by determining the minimum inhibitory concentrations. In addition, antiquorum sensing activity was assessed using Chromobacterium violaceum, enabling the direct observation of the inhibitory effect on violacein synthesis, which is regulated by this cell-tocell communication mechanism. The results highlight the promising potential of producing yacon leaf extracts through PLE, promoting a more sustainable process and yielding bioactive compounds with potential applications in the food, pharmaceutical, and cosmetic industries.
Metaverso como ambiente de trabalho para times ágeis: uma proposta de requisitos de design
(Universidade Federal de São Carlos, 2025-04-08)
Oliveira, Fabricio Malta de
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Zaina, Luciana Aparecida Martinez
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https://lattes.cnpq.br/0192085115595443
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https://orcid.org/0000-0002-1736-544X
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https://lattes.cnpq.br/8534774168648227
In recent years, remote work in software development has become increasingly common, driving the search for solutions that enhance communication and collaboration among distributed teams. Within this context, the metaverse emerges as a promising alternative by offering a three-dimensional, immersive, and persistent virtual environment capable of making remote experiences more similar to face-to-face interactions. Although Scrum is widely adopted, its use in remote settings remains focused on Distributed Agile Development through traditional two-dimensional tools, revealing a gap regarding its implementation in the metaverse. This study proposes a set of design requirements to adapt Scrum for the metaverse, aiming to optimize collaboration in remote software teams. The research was structured into five main stages: a literature review to identify related studies; an exploratory study to characterize the metaverse and its applications; an analysis of challenges faced by distributed teams to inform Scrum requirements; the proposal of design requirements followed by prototyping; and finally, an evaluation of these requirements with professionals in the field. The exploratory study identified key characteristics of the metaverse, such as immersive space, along with attributes like personalization, interoperability, and compatibility with immersive technologies. A subsequent literature review on the challenges of remote agile teams supported the definition of both cross-cutting requirements—such as faithful presence through avatars—and specific requirements for Scrum ceremonies, including sprint planning. The prototype featured avatars, 3D kanban boards, and interactive tools, and was evaluated by 12 experienced software development professionals. Quantitative analysis using the Igroup Presence Questionnaire (IPQ) revealed a high perception of spatial presence, while semi-structured interviews highlighted benefits such as increased focus, improved collaboration, and enhanced team cohesion. The findings suggest that the metaverse can help remote teams more closely approximate the dynamics of in-person work.
Detecção de propagadores influentes por aprendizado de máquina
(Universidade Federal de São Carlos, 2025-04-09)
Bugada, Vitória de Camargo
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Peron, Thomas Kauê Dal'Maso
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https://lattes.cnpq.br/1087642697727776
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Branco
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https://lattes.cnpq.br/0964383127189148
The study of complex networks is essential to understanding interconnected systems in areas such as biology, sociology and technology. These networks, made up of nodes and edges, reveal important emerging patterns. Network analysis allows you to optimize interventions and improve systems resilience. The identification of influential propagators in a network, such as those responsible for the spread of diseases or information, is fundamental and depends on the dynamics of the phenomenon. Different approaches such as k-shell analysis and optimization models help predict these propagators. This study seeks to analyze the relationship between centrality measures and the propagation capacity in social and spatial networks, proposing prediction models to identify the main influencers and optimize dissemination control.
Os estigmas sobre o rural nas políticas público-territoriais: o caso das demarcações rural-urbanas nos planos diretores de São Carlos - SP
(Universidade Federal de São Carlos, 2025-04-09)
Roldão, Afonso Henrique
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Martins, Rodrigo Constante
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https://lattes.cnpq.br/6617183095074852
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https://orcid.org/0000-0003-2700-3319
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https://lattes.cnpq.br/9247114826135364
Considering the institutional nature of territorial management, which sometimes ignores qualitative aspects of the landscape, this paper analyzes the treatment given to rural areas and ruralities in the panorama of territorial management in the municipality of São Carlos. Firstly, in a contextualizing way, looking for historical clippings and aspects of legal evolution at the municipal level. In addition, the scope of the research characterized São Carlos' territorial management through the two versions of its Master Plan, a public policy established by the City Statute (Law No. 10.257/2001). This public-territorial policy, which was first implemented in the municipality in 2005 (Law No. 13.691/2005), had its original version replaced by a new plan in 2016 (Law No. 18.053/2016), and both versions have undergone significant changes over the years. In this sense, the applied research sought to analyze the view of rural areas in the municipality through this group of laws, which often aimed to change zoning, transforming rural areas into new urban areas, considering the existence of a continuum and promoting socio-environmental impacts. Therefore, the main focus of the research was the search for a descriptive synthesis of how rural areas were seen and portrayed by public authorities. To this end, in addition to an in-depth literature review, an analytical category was applied to the legislation analyzed, based on studies carried out by multilateral institutions, such as the OECD, and works by authors such as Milton Santos and José Eli da Veiga, among others, based on the methodology for analyzing situations left by Milton Santos in his 1988 production. In this way, by going through the definitions of space, territory and rural areas, the established political structure and the application of the laws, a synthesis guided by a critical sense was built, and not just a review of the legislation.
Índice de severidade e SIG combinados para identificar e caracterizar a sinistralidade de trânsito em município de pequeno porte
(Universidade Federal de São Carlos, 2025-04-10)
Bellintane Júnior, Cláudio
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Guerreiro, Thais de Cassia Martinelli
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https://lattes.cnpq.br/2650555786682535
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https://lattes.cnpq.br/5192349156513503
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https://orcid.org/0009-0003-1218-4302
The disorderly growth of cities has caused many urban problems, including unplanned urban mobility focused on motor vehicles, resulting in numerous traffic accidents, loss of life, and significant social and economic losses. This growth has also affected small cities, such as the city of Novo Horizonte/SP, the object of this research. The city has approximately 39 thousand inhabitants and a fleet of more than 32 thousand vehicles. In addition, the urban mobility problems are the same as in large cities, although to a lesser extent, but causing similar effects. Given the above, this research combines the severity index, through the calculation of the UPS, with GIS to identify the critical points of accidents in the city of Novo Horizonte. The methodology applied consisted of collecting accident data from the period between 2018 and 2023 from police reports prepared by the Military Police of the State of São Paulo. Based on the processing and systematization of the data, the severity index was calculated to define the critical points, according to the severity of each traffic accident. The data was then georeferenced in a GIS, from which it was possible to create Kernel Density Maps that showed the areas with the highest concentration of severity. The research identified the roads and critical points with the highest severity, in addition to analyzing the times and days of the week related to the accidents. Detailed data on victims revealed that the most vulnerable groups (motorcyclists, pedestrians, and cyclists) require priority in actions and interventions since they represented 70.83% of the total deaths recorded in the period from 2018 to 2023.
Diagnóstico de estilos de aprendizagem em biologia e implementação de atividades correlatas: quais são suas implicações na aprendizagem?
(Universidade Federal de São Carlos, 2025-04-11)
Gaspar, Priscila Borges Dalbem
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Zanon, Dulcimeire Aparecida Volante
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https://lattes.cnpq.br/1811225448261362
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https://orcid.org/0000-0002-3728-6175
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https://lattes.cnpq.br/5274001561703346
Teaching is a complex challenge, especially in classrooms composed of students with different learning profiles. To address this reality, several models have been developed to identify students’ learning styles and, consequently, assist teachers in their work. These models have been applied at different educational levels as diagnostic tools to help map students’ needs and preferences, thereby contributing to more effective pedagogical decisions. In this context, the present study aimed to analyze the learning styles in Biology of first-year high school students in a vocational education school located in the interior of São Paulo state. Additionally, it sought to implement teaching activities related to these learning styles to identify their implications for student learning. To achieve this, we used the New Index of Learning Styles (N-ILS) questionnaire, adapted by Vieira Júnior (2012). Due to the specific focus on Biology, linguistic and metalinguistic adjustments were made to the instrument’s questions. A total of 35 students participated in the study, and the results indicated a predominance of active, sensing, visual, and sequential learning profiles. These profiles suggest a preference for participatory, experimental, and logically organized approaches. Based on this data, considering the study’s objective and the first-year high school curriculum, we adopted the Science, Technology, and Society (STS) perspective as our theoretical-methodological framework. This approach is particularly relevant for fostering interest in Science and promoting problem-solving in decision-making processes. From the STS perspective, a set of teaching activities was designed and implemented throughout the second bimester of 2024. To assess the implications of these activities on student learning while correlating them with the identified learning styles, we applied Discursive Textual Analysis (DTA). This qualitative approach enabled a deeper understanding of the investigated phenomena, facilitating the reconstruction and expansion of knowledge on the covered topics. Overall, the results indicated that most students perceived the adaptation of activities as positive, validating the effectiveness of the implemented practices. However, the findings also highlight the importance of diversifying tools and pedagogical strategies to address an even broader spectrum of learning profiles.
Elaboração, aplicação e análise de aulas em perspectiva dialógica de ensino-aprendizagem sobre Sistemática Vegetal para o ensino fundamental I
(Universidade Federal de São Carlos, 2025-04-11)
Oliveira, Matheus Fernando Custódio de
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Calzolari Neto, Anselmo João
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https://lattes.cnpq.br/4906309581958797
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https://orcid.org/0000-0002-6703-9079
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Sebastiani, Renata
Botany is a science that encompasses all aspects related to plants, and is important and forms part of the major area of Biology. Plant Systematics is the main constituent axis of Evolutionary Biology. However, regarding the teaching and learning aspects of this axis in Basic Education schools, several authors have raised questions and problems, identifying it as ineffective, repetitive and memorizing. Despite this, there are few studies that contribute to overcoming the barriers already known. Thus, this research presents the development, application and analysis of classes in a dialogical perspective of teaching and learning about Plant Systematics for Elementary Education. For this, the classes were based on Freire's Thematic Approach, being divided into three Pedagogical Moments: problematization, organization of knowledge and application of knowledge. Successful Educational Actions were incorporated to compose the stages. The research was conducted in a municipal school in the city of Limeira/SP, in a 5th grade Science class. Based on the Communicative Methodology, the data were collected, analyzed and agreed upon through the Communicative Observation Diary and the Communicative Focus Group. Furthermore, the knowledge present in the students' records during the activities was quantified based on the presence of key words in the answers, accounted for by the correction/verification of learning impressions and analyzed according to the typology of knowledge proposed by Eric Gutstein, evidencing an approval rate of 72.7%, that is, above the institutional school average (5). As a result of this analytical process, the results of learning impressions were compared with the exclusionary and transformative elements identified in the diary and in the focus group, verifying the contributions in relation to Dialogical Learning, as a theoretical methodological framework, and in relation to the presence of Classical, Community and Critical knowledge on Plant Systematics, as well as that brought by the students from reading the world. Furthermore, the interference of variables was considered, such as teaching experience and experience with Successful Educational Actions, as an analytical process of the practice of the ambiguous role of teacher and researcher.
Obtenção de hidrogéis à base de amido e nanocelulose para potencial aplicação na agricultura
(Universidade Federal de São Carlos, 2025-04-11)
Hernandez, Cécile Chaves
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Pereira, Robson Valentim
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https://lattes.cnpq.br/1675940843759718
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https://orcid.org/0000-0002-3314-8752
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Menezes, Aparecido Junior de
Hydrogels, due to their porous three-dimensional structure, have the ability to swell, absorbing fluids, a very important property when they are intended to be used in the field of agriculture as a superabsorbent polymer, helping to control soil moisture; as a soil conditioner, performing a controlled delivery of fertilizers and other agrochemicals or even for the removal of metal ions that accumulate in the soil due to its natural non-degradation. The present study proposes the preparation of a hydrogel obtained through a matrix of starch (cassava and arrowroot)/xanthan gum and starch (cassava and arrowroot)/xanthan gum with cellulose nanofibrils (CNFs) ionically, covalently and double crosslinked, forming a nanocomposite, to obtain better mechanical and physicochemical properties. The characterization techniques used in this study were: Differential Scanning Calorimetry (DSC), determination of Viscosity Average Molar Mass (Mv), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), thermogravimetric analysis (TG), X-ray diffraction (XRD) and swelling analysis. It was observed that the different morphologies and amylose/amylopectin contents of the starches influence their viscosities, which directly interferes in the analyzed properties and that the presence of xanthan gum, and the crosslinks contribute to the formation of a dense and compact structure in the hydrogels. Double crosslinking produces an appearance of inflexibility and rigidity in the hydrogel. The density of the network formed after crosslinking and the presence of CNFs interfered in the thermal and swelling properties, causing a decrease in thermal stability and mass loss, with the main peak of mass loss between 153 °C and 167 °C, while for starch it occurs above 300 °C. After these analyses, it can be concluded that the presence of NFC in the hydrogels reduced the swelling power, since the interactions between NFC and starch reduce the mobility of the network. Good results were obtained for the different starch hydrogels and that covalent crosslinking confers greater swelling power to the material, with swelling power above 1000%. The results obtained for the covalently crosslinked samples being superior to those obtained by ionic crosslinking and doubly crosslinked.