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Modificação química de quitosana com etoximetilenos: otimização reacional, caracterização e aplicação na adsorção de cristal violeta e diclofenaco
(Universidade Federal de São Carlos, 2026-03-31) Mathias, Samir Leite; Dufresne, Alain; https://lattes.cnpq.br/2836712749450886; https://orcid.org/0000-0001-8181-1849; Menezes, Aparecido Junior de; https://lattes.cnpq.br/0484426340349483; https://orcid.org/0000-0001-5638-489X; https://lattes.cnpq.br/6213405782757403; https://orcid.org/0000-0003-0523-9566; Dragunski, Douglas Cardoso; Fakhouri, Farayde Matta; Delezuk, Jorge Augusto de Moura; Oliveira, Gean Henrique Marcatto de; https://lattes.cnpq.br/0612112281360342; https://lattes.cnpq.br/5929693866996351; https://lattes.cnpq.br/0626530760941869; https://lattes.cnpq.br/2892871093566684; https://orcid.org/0000-0001-7870-097X; https://orcid.org/0000-0002-7031-3366; https://orcid.org/0009-0000-2254-340X; https://orcid.org/0000-0002-4403-3643
The increasing presence of organic contaminants in aquatic environments has stimulated significant interest in the development of new adsorbent materials capable of efficiently removing these compounds from water. Among the materials investigated for this purpose, chitosan stands out as a promising biopolymer due to its abundance, biodegradability, and the presence of reactive functional groups along its polymeric backbone. However, the adsorption performance of chitosan can be significantly enhanced through chemical modifications that alter its structure and surface properties. In this context, the aim of this project was to develop functionalized chitosan derivatives through nucleophilic vinylic substitution reactions using alkoxymethylene derivatives bearing different substituent groups, and to investigate how the electronic nature and density of these functional groups influence the adsorption performance of the material. Initially, chitosan was modified using (Ethoxymethylene)malononitrile, allowing the establishment of suitable reaction conditions for polymer functionalization through the formation of conjugated enamine structures, achieving a degree of substitution of up to 0.91. Subsequently, new chitosan derivatives were synthesized using Diethylethoxymethylenemalonate and Ethyl 2-cyano-3-ethoxyacrylate (Ethyl (ethoxymethylene)cyanoacetate), introducing diester and ester–nitrile groups, respectively. For these systems, reaction conditions were optimized using a design of experiments approach in order to maximize the degree of polymer functionalization. The obtained materials were characterized by different analytical techniques to evaluate the structural and physicochemical modifications resulting from the introduction of these functional groups. The adsorption performance of the synthesized derivatives was evaluated for the removal of model organic contaminants from aqueous solutions, including the dye crystal violet and the pharmaceutical compound diclofenac. The results demonstrated that chemical modification of chitosan significantly altered the surface properties of the material, directly influencing its adsorption capacity. An increase in the density of functional groups along the polymer chain led to enhanced affinity between the adsorbent material and the investigated contaminants, reaching a maximum adsorption capacity on the order of 219 mg.g-1 for diclofenac and 383 mg.g-1 for violet crystal. Overall, the results obtained in this thesis demonstrate that the chemical modification of chitosan through nucleophilic vinylic substitution reactions represents an efficient strategy for the development of new biopolymer-based adsorbent materials. In addition to improving the adsorption performance of chitosan, this synthetic approach also opens new perspectives for the development of functional polymeric materials with tunable properties for environmental applications.
A terceira margem da literatura: transferências entre sistemas de cultura em The Last Of Us Parte 2
(Universidade Federal de São Carlos, 2026-03-31) Lisita, Bianca Francischini; Rocha, Rejane Cristina; https://lattes.cnpq.br/5669300635333699; https://lattes.cnpq.br/0363783716038166; https://orcid.org/0000-0003-2735-0185; Devides, Dilson César; Moreira, Maria Elisa Rodrigues; Prado, Márcio Roberto do; Pereira, Vinícius Carvalho; https://lattes.cnpq.br/0899073083024191; https://lattes.cnpq.br/8503000442103169; https://lattes.cnpq.br/3428352082823972; https://lattes.cnpq.br/5304593788129950
This thesis investigates The Last of Us part 2 through the lens of Polysystem Theory (Even-Zohar, 1990), proposing that the game constitutes a nomadic product that inhabits a “third margin” between the print literary system, the digital literature system, and the electronic games system. Drawing on the Rosian metaphor of the crossing—which informs both the methodological gesture and the analytical trajectory—the study problematizes the historical indefinition of the literary object, arguing that literariness is not an intrinsic attribute of the text but rather the result of systemic forces mobilized by institutions, repertoires, producers, consumers, and markets. The first part examines the print literary system, highlighting its central position within the literary polysystem and the legitimizing role of the book, singular authorship, and inherited repertoires from a tradition which, although dominant, remains in constant tension with peripheral strata. The study then analyzes the digital literature system, focusing on the role of the Electronic Literature Organization and showing how multimodality, algorithmic processes, and material experimentation broaden the notion of literariness beyond the written word. In this third margin, The Last of Us part 2 is shown to function as a catalyst for frictions among these systems: its audiovisual narrative, its sensorial reading aesthetics, and its programming as a meaning-making agent instantiate what the dissertation terms a “novel of images,” a mode of narrativity that displaces the reader-player into a hybrid interpretive position. The analysis also reveals a crisis of authorship, disputes over legitimacy, and tensions between expectations of interactivity and authorial control within the game system. These conflicts confirm that the product is the core of a systemic misalignment, challenging stable taxonomies and demonstrating that contemporary cultural objects circulate across mutually influencing systems. The study concludes that The Last of Us part 2, by refusing a fixed position, makes visible the polysystem’s own movement: a literature in transit that requires of the researcher not the comfort of familiar margins, but the courage to inhabit the center of the river, where new narrative forms emerge and take shape.
Coumarin–dihydropyrimidinone hybrids as promising agents against ovarian cancer: synthesis, SAR, and in silico evaluation
(Universidade Federal de São Carlos, 2026-03-31) Santos, Jhonathan dos; Martinez, Alice; Abe, Saulo Henrique Mendes; Mello, Marcos Vinícius Palmeira de; Santos, João Pedro Araujo dos; Rodrigues, Carlos Rangel; Souza, Alessandra Mendonça Teles de; Batista, Alzir Azevedo; Corrêa, Arlene; https://lattes.cnpq.br/3969751736153847; https://lattes.cnpq.br/4564844871404847; https://lattes.cnpq.br/5849485134436738; https://lattes.cnpq.br/8894654634441028; https://lattes.cnpq.br/6963882962472772; https://lattes.cnpq.br/4265523459861860; https://lattes.cnpq.br/7047409069633400; https://lattes.cnpq.br/6469642481998660; https://lattes.cnpq.br/7425467156776144; https://orcid.org/0000-0003-2550-5315
The coumarin scaffold is widely recognized for its broad range of biological activities, including antibacterial, anti-HIV, and anticancer properties. In parallel, molecular hybridization has emerged as an effective strategy to enhance biological activity and expand chemical diversity within drug discovery libraries. In this study, a series of coumarin–dihydropyrimidinone (DHPM) hybrids were synthesized via a Biginelli multicomponent reaction. The in vitro cytotoxic activity of these compounds was evaluated against a panel of cancer cell lines. A structure–activity relationship (SAR) analysis was carried out to elucidate the influence of different substituents and physicochemical properties on anticancer activity. Among the synthesized compounds, LSPN925 emerged as a good anticancer candidate and was further investigated for its effects on cell morphology and colony formation. In addition, in silico pharmacokinetic and toxicological evaluations were performed for the most active compounds to predict their drug-likeness and safety profiles. The preliminary SAR analysis revealed that lipophilicity and molecular volume of the compounds play a critical role in modulating their cytotoxic activity, highlighting these parameters as key considerations in the rational design of new coumarin-based anticancer agents. Overall, these findings support the potential of coumarin–DHPM hybrids as promising scaffolds for further anticancer drug development.
A educação midiática e o discurso neoliberal nas plataformas digitais educacionais de formação docente de língua portuguesa
(Universidade Federal de São Carlos, 2026-03-31) Souza, Parla Camila dos Reis de; Sargentini, Vanice Maria Oliveira; http://lattes.cnpq.br/1406919572611392; https://orcid.org/0000-0002-7760-3075; https://lattes.cnpq.br/2923838793375892; Rosa, Marluza Terezinha da; Ribeiro, Jocenilson; Carvalho, Pedro Henrique Varoni de; Onofre, Marília Blundi; http://lattes.cnpq.br/7452330796648673; http://lattes.cnpq.br/8985943014913431; http://lattes.cnpq.br/0019513394358070; http://lattes.cnpq.br/4908382415301882; https://orcid.org/0000-0002-3590-1752; https://orcid.org/0000-0001-8716-5059; https://orcid.org/0000-0002-7075-310X
This dissertation examines how the Brazilian educational digital platforms EducaMídia and Escolas Conectadas construct Media Education within a broader field structured by neoliberal rationality. Drawing on Michel Foucault’s concepts of archive, veridiction, tékhne, and parrhesia, I analyze how these platforms position themselves as legitimate authorities in the training of Portuguese Language teachers in Basic Education, thereby displacing the public university from its historically established role in teacher formation. The corpus is constituted, in Foucauldian terms, as an archive comprising EdTech mapping reports, national guidelines and regulatory documents issued by the Ministry of Education (MEC), editorials and institutional materials produced by the platforms, and technical notes from INEP concerning the acquisition of digital devices and internet access in Brazilian public schools. This archive enables an examination of the ongoing platformization of Basic Education, with particular attention to its epistemic claims, economic investments, and institutional entanglements. I argue that the consolidation of platform-based Media Education is closely linked to increased investment in educational startups and to policy decisions by MEC that favor digital mediation and competency-based frameworks. Through a discourse-analytic reading informed by Christian Laval and Pierre Dardot’s account of neoliberal governmentality, I demonstrate how the platforms mobilize tékhne as a regime of technical expertise that produces pedagogical “enchantment” through design, usability, and apparent efficiency. Simultaneously, their short-term training formats and modular courses reproduce neoliberal logics of flexibilization, responsibilization, and market-oriented accountability, thereby legitimizing public expenditures at the municipal, state, and federal levels that sustain the infrastructure of platformization. Pedagogically, I show that the lesson plans, workshops, and training modules offered by these platforms are characterized by the absence of explicit bibliographic grounding, the lack of articulated methodological frameworks, and a marked superficiality in their treatment of multimodal and journalistic-media genres. These genres are objectified and didacticized in ways that reduce their discursive complexity. I contend that this configuration functions as a mechanism of subjection—what Foucault conceptualizes as a process of minoritization—through which teachers are incorporated into platform-dependent forms of professional practice.