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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.
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; https://orcid.org/0009-0003-9219-1472
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.
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; https://orcid.org/0000-0001-5240-4654; https://lattes.cnpq.br/2886656846177916; https://orcid.org/0000-0001-5357-0291
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.
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; https://orcid.org/0000-0002-3349-8648; https://lattes.cnpq.br/5370586071224244; https://orcid.org/0009-0004-5500-4209
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.
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; https://orcid.org/0000-0003-1276-7420; Costa, Roberto César Reis da; Leite, Tarcisio de Arantes; Martins, Diléia Aparecida; Silva, Vera Lucia Teixeira da; https://lattes.cnpq.br/1729585565660340; https://lattes.cnpq.br/7285343180848313; https://lattes.cnpq.br/4802875511597756; https://lattes.cnpq.br/4421134009136228; https://orcid.org/0000-0003-2373-6929; https://orcid.org/0000-0001-9288-5982; https://orcid.org/0000-0002-0450-1246; https://orcid.org/0000-0002-6167-7205
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.
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; Aguiar, Ana Carolina de; https://lattes.cnpq.br/6206317990010266; Pimentel Filho, Natan de Jesus; https://lattes.cnpq.br/9157232954010211; https://lattes.cnpq.br/0145015483494323
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.