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Motivações e percepções de consumidores sobre veículos híbridos e elétricos: um estudo na região de Campinas/sp
(Universidade Federal de São Carlos, 2026-01-27) Anastacio, Evelyn Rodrigues; Hoffmann, Wanda Aparecida Machado; http://lattes.cnpq.br/7609135667093837; https://orcid.org/0000-0002-1359-1802; https://lattes.cnpq.br/3545720742004188; https://orcid.org/0009-0006-5002-4934; Junior, Roberto Ferrari; Cunha, Christiano França da; http://lattes.cnpq.br/1581806209106850; http://lattes.cnpq.br/6209953252761209; https://orcid.org/0000-0003-3213-5084; https://orcid.org/0000-0002-2590-3818
This study aims to analyze the purchase motivations of consumers of hybrid and electric vehicles in the Campinas/SP region. A qualitative approach with an exploratory and interpretive character was adopted, grounded in theoretical frameworks from marketing, consumer anthropology, and sustainability studies. Data collection was conducted through semi-structured interviews with owners of these vehicles. In the specialized literature, electromobility is often associated with attributes of environmental sustainability. However, the results indicate that, in the context investigated, purchase decisions are predominantly driven by economic factors related to cost–benefit considerations, while technological attributes play a complementary role. Environmental sustainability proved to be secondary, being mobilized instrumentally within economic evaluations. The findings highlight a mismatch between green marketing discourses and the motivations effectively activated in consumer behavior within the field of electromobility.
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; http://lattes.cnpq.br/2836712749450886; https://orcid.org/0000-0001-8181-1849; Menezes, Aparecido Junior de; http://lattes.cnpq.br/0484426340349483; https://orcid.org/0000-0001-5638-489X; http://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; http://lattes.cnpq.br/0612112281360342; http://lattes.cnpq.br/5929693866996351; http://lattes.cnpq.br/0626530760941869; http://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.
Química de fluxo contínuo aplicada à síntese de insumos farmacêuticos ativos (IFAs): buclizina
(Universidade Federal de São Carlos, 2026-02-24) Ramos, Tiago de Oliveira; Oliveira, Kleber Thiago de; http://lattes.cnpq.br/3759761373942891; http://lattes.cnpq.br/2022842122029233; Corrêa, Arlene Gonçalves; Souza, Rodrigo Octavio Mendonça Alves de; http://lattes.cnpq.br/7425467156776144; http://lattes.cnpq.br/0941546772583856
The development of novel synthetic routes for the production of Active Pharmaceutical Ingredients (APIs) is pivotal not only for establishing more sustainable and competitive manufacturing processes but also for the training of new professionals seeking to enter this sector. Among modern synthetic technologies offering significant advantages for API manufacturing, continuous flow synthesis stands out. This approach contributes to enhancing synthetic systems by improving scalability and productivity, reducing solvent consumption, increasing automation levels, and ensuring greater process safety. In this work, the synthesis of the API buclizine is presented comprising four steps, all performed under continuous flow conditions. Initially, a continuous flow photocatalyzed reductive amination between piperazine and 4-tert-butylbenzaldehyde was carried out, scaled up to the gram scale with a productivity of 10.7 g/day. Subsequently, the electrochemical reduction of 4- chlorobenzophenone was performed, also on a gram scale, achieving a productivity of 6.6 g/day. The resulting product then reacted with hydrochloric acid to convert the alcohol into its corresponding chloride, reaching a productivity of 86 g/day due to the short residence time and high concentration of the reaction mixture. Finally, the chloride intermediate was reacted with the product from the photocatalytic step via a nucleophilic substitution reaction, yielding buclizine. This step produced 1.5 g of the API with a productivity of 9.4 g/day, representing a gram-scale proof-of-concept for the continuous synthesis of this pharmaceutical ingredient.
Photodynamic action of Pd(II)/porphyrin complexes against melanoma cells
(Universidade Federal de São Carlos, 2026-05-05) Moraes, Edynara Cruz de; Palmeira-Mello, Marcos Vinicius; Silva , Lívia do Carmo; Curcio, Juliana Santana De; Graça, Alex Marchezini; Dutra, Jocely Lucena; Alonso, Antonio; Souza, Guilherme Rocha Lino de; Batista, Alzir Azevedo; Silveira-Lacerda , Elisângela de Paula; Gonçalves , Pablo José; http://lattes.cnpq.br/6784675018819363; http://lattes.cnpq.br/8894654634441028; http://lattes.cnpq.br/7092484043564604; http://lattes.cnpq.br/9577753232871923; http://lattes.cnpq.br/1230958955676787; http://lattes.cnpq.br/7966283355473231; http://lattes.cnpq.br/5013069863616789; http://lattes.cnpq.br/1127532567066692; http://lattes.cnpq.br/6469642481998660; http://lattes.cnpq.br/9390789693192751; http://lattes.cnpq.br/0515343409614452; https://orcid.org/0000-0003-2550-5315
Photodynamic therapy (PDT) is an emerging strategy for cancer treatment and represents a promising approach for melanoma, one of the most aggressive and therapy-resistant forms of skin cancer. In this study, meso-tetra(4-pyridyl)porphyrin complexes coordinated with palladium(II)/diphosphine ligands (Porf@dppe, Porf@dppp, Porf@dppb, and Porf@dppf; dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino) propane, dppb = 1,4-bis(diphenylphosphino)butane, and dppf = 1,1′-bis(diphenylphosphino)ferrocene), previously shown to display favorable lipophilicity and efficient singlet oxygen production, were evaluated againsthuman (A375) and murine (B16–F10) melanoma cells, as well as non-cancerous keratinocytes (HaCaT). Cytotoxicity measured after a 90 min incubation period yielded dark IC50 values between 0.6 and 8.6 μM, whereas light irradiation (λ = 415 nm, 1.8 J cm􀀀 2, 36 mW cm􀀀 2) resulted in markedly lower IC50 values in the nanomolar range (2–27 nM). Irradiation increased intracellular ROS levels, induced morphological alterations in A375 cells, inhibited long-term proliferation, and reduced cell migration, particularly for Porf@dppb and Porf@dppf. The highest cytotoxicity was observed for Porf@dppf, likely due to the redox-active ferrocene unit promoting Fentontype reactions and enhanced hydroxyl radical formation. Electron paramagnetic resonance (EPR) spin-trapping experiments confirmed light-induced generation of hydroxyl radicals and superoxide anion, with significantly higher hydroxyl radical production observed for Porf@dppf. The photodynamic activity of these complexes is attributed to efficient ROS production involving simultaneous contributions from both Type I and Type II mechanisms. Moderate binding to bovine serum albumin suggests possible albumin-mediated plasma transport. Overall, palladium(II)/diphosphine porphyrin complexes emerge as promising photosensitizers for melanoma photodynamic therapy.
Transferência de aprendizado profundo para previsão da irradiação solar: uma análise para diferentes bioclimas e escassez de dados
(Universidade Federal de São Carlos, 2026-03-02) Diniz, Leonardo; Barbosa, Daniel; http://lattes.cnpq.br/7843695359589199; https://orcid.org/0000-0002-0542-1723; Fernandes, Ricardo; http://lattes.cnpq.br/0880243208789454; https://orcid.org/0000-0003-2361-6505; https://lattes.cnpq.br/6784659523460869; https://orcid.org/0009-0001-0657-5409; Machado, Vinicius; Palito, Thamyres; http://lattes.cnpq.br/9385561556243194; http://lattes.cnpq.br/0882441206072709; https://orcid.org/0000-0003-3391-8443
The intermittent nature of solar irradiation has been a major challenge in planning and operating electrical power systems. In Brazil, due to the distinct bioclimatic zones, each with its own peculiarities and climatic behaviors, the sce- nario becomes complex. For this reason, a methodology based on transfer learning combined with state-of-the-art solar irradiation forecasting can bring advantages, especially when there is a low amount of data from certain climatological stations. In this sense, transfer learning can be used both between data from stations be- longing to the same bioclimatic zone (aiming to solve the problem of missing data) and between data from stations located in different bioclimatic zones (seeking to solve the problem of climatic disparity). This work proposes, based on a baseline constructed with the seasonal autoregressive integrated moving average model, to evaluate the performance of LSTM (long-short term memory) neural networks and their hybridization with convolutional neural networks (CNNs) in order to perform hourly solar irradiance forecasting. The results demonstrate that, in relation to the test of models constructed solely by LSTMs, compared to the CNN-LSTM hybrid models, the former showed slightly better performance, by approximately 1% on av- erage. Regarding the learning transfer tests, the feature extraction and fine-tuning approaches performed reasonably well when compared to zero-shot adaptation, be- ing comparable to the results of the LSTM models for each climatological station, especially in the configuration of stations by distance. Regarding the configuration of stations with a low amount of data, the approach performed well, mainly within the MAE metric.