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Avaliação da eficácia do óleo essencial de Melaleuca encapsulado em pectina cítrica no controle in vitro de Leucoagaricus gongylophorus
(Universidade Federal de São Carlos, 2025-03-26)
Moreira, Bruno Ricardo
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Forim, Moacir Rossi
;
https://lattes.cnpq.br/1234565160573730
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https://lattes.cnpq.br/5084844653825682
Leaf-cutting ants of the genera Atta and Acromyrmex are widely found in Brazil. These social insects collect plant material to use as a substrate for the symbiotic cultivation of the fungus Leucoagaricus gongylophorus, with which they maintain a mutualistic relationship. However, this foraging activity causes damage to human activities related to forestry, grazing, and agriculture. The control of these ants is generally carried out using chemical agents, which may have harmful effects on the environment and human health. An alternative approach involves the use of plant secondary metabolites to control these populations. However, such compounds are often unstable and difficult to control in terms of release. To address these issues, an encapsulation process using biopolymers has been explored. The main objective of this study was to develop a formulation aimed at controlling leaf-cutting ants. The approach was based on the use of essential oil from Melaleuca alternifolia, also known as tea tree. This essential oil is widely used in hygiene products and as a herbal remedy for skin conditions, among other uses, and has proven effectiveness in microbial control. The first part of the study consisted of biological assays to evaluate the activity of the essential oil on the growth of the symbiotic fungus at various concentrations. Complete inhibition was observed at concentrations above 15 microliters. Based on a literature review on biopolymers, citrus pectin was selected as the encapsulating agent. To develop the formulation method, several experiments were conducted with variations in process parameters, aiming to maximize encapsulation yield. This yield was quantified using gas chromatography coupled with mass spectrometry, employing the headspace technique. A formulation with approximately 84% yield was obtained. Using this formulation, a biological assay was carried out to evaluate its effect on the growth of L. gongylophorus, resulting in 80% fungal growth inhibition. These results indicate that the developed formulation may serve as an ecological and effective alternative to conventional compounds for the control of leaf-cutting ants.
Hidroxipropilação de amido e fibras de resíduo de açaí para obtenção de biocompósitos
(Universidade Federal de São Carlos, 2025-03-26)
Lopes, Henrique Solowej Medeiros
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Komatsu, Daniel
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https://lattes.cnpq.br/2620060426867863
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Dufresne, Alain
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http://lattes.cnpq.br/2836712749450886
Within the context of materials engineering, starch stands out as a sustainable source for the production of biofilms, due to its biodegradability and its renewable source of high produc-tion in several different climates and regions. However, pure starch materials have insuffi-cient properties for their wide application in industry and commerce, and hydroxypropyla-tion is a sustainable way to reduce the hydrophilic and fragile character of the material. In this study, cassava starch and açaí residue were chemically modified by hydroxypropylation. The combination of parameters for sample preparation was performed by a design of exper-iments 2³ full factorial. The substrates were previously activated with KOH in water and ethanol solution, modified in different molar ratios (0.4, 0.6 and 0.8 OHPO/OHglucose), tem-peratures (115, 125 and 135 °C) and açaí residue proportions (0, 5 and 10 wt%). The effects of each defined parameter were evaluated by analysis of variance (ANOVA), revealing that the molar ratio and the higher amount of açaí residue significantly increased the mass gain, while the temperature had the opposite effect. The structural characterization by FTIR and solid-state NMR confirmed the chemical modification through the identification of methyl bond peaks, with quantification of the degree of substitution by elemental analysis and sol-id-state NMR, varying between 0.1 and 0.4, as the molar ratio increases and the temperature decreases. Notably, complete gelatinization of starch was observed during the reaction, evi-denced by the absence of crystalline structures in XRD and SEM. However, homopolymeri-zation of propylene oxide (PPO) has been observed, resulting in the intermolecular presence of PPO in the polymer chains, significantly increasing the plasticization of the material. This plasticization can be observed by TG and DSC, which indicate a reduction in thermal stability, in addition to accelerated retrogradation with the formation of short- and long-range crystalline structures via XRD and FTIR, especially in samples containing açaí resi-due. Due to the previous plasticization of starch, films were obtained via casting at room temperature with significant lower amount of glycerol (7.5% starch weigh basis), resulting in materials with 470% high elongation at break, although with lower maximum tensile strength stress, greater hydrophilicity and tendency to retrogradation. The results demon-strate the potential of chemical modification of starch to expand its applications in sustaina-ble packaging, due to the success in the low use of synthetic plasticizers achieved.
Cerâmicas bioinspiradas recobertas com óxidos perovskíticos para aplicação em catálise por plasma de micro-ondas
(Universidade Federal de São Carlos, 2025-03-26)
Cardoso, André Lair Ferreira
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Muche, Dereck Nills Ferreira
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https://lattes.cnpq.br/6542991023278848
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Gunnewiek, Rodolfo Foster Klein
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https://lattes.cnpq.br/5185829124608696
Climate changes related to global warming are directly associated with greenhouse gases emissions, mostly originated from fossil fuels. To help mitigate these gases emissions, the viability of advanced catalytic techniques, such as microwave plasma catalysis, are evaluated. This thesis aims to produce a bioinspired ceramic by microwave sintering to be used as support for catalytic particles for microwave plasma catalysis. The support was produced by conventional and microwave sintering, achieving a 35% reduction in energy consumption when sintered by the microwave technique. The catalytic ceramics, BaTiO3, SrTiO3, Ba0,5Sr0,5TO3 and MgTiO3, were synthesized by the conventional or microwave assisted Pechini method, followed by analysis of the resulting powder using X-ray diffraction, scanning and transmission electron microscopy, and diffuse reflectance spectroscopy. The particle deposition over the bioinspired support was carried out, investigating their microwave plasma resistance. It was noted that the particles protected the support from plasma ablation and sputtering. The plasma resistance under Argon or Nitrogen microwave plasmas of the bulk titanate ceramics were also investigated, evaluating their microstructural stability, densification and modification of electrical and dielectric properties regarding the sintering technique and type of plasma treatment. The SrTiO3 composition presented the best plasma resistance, while others were also resistant to plasma ablation and sputtering. All compositions presented high values of dielectric constant, foreseeing a decent application as catalytic materials in microwave plasma catalysis.
A influência do ambiente escolar e do letramento em cultura africana na crença de autoeficácia docente para o ensino dos objetos de conhecimento de matriz africana nas aulas de educação física
(Universidade Federal de São Carlos, 2025-03-26)
Alvares, Luis Eduardo
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Godoi Jacomassi, Daniela
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https://lattes.cnpq.br/7699007812483790
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https://lattes.cnpq.br/2715455816295604
Despite the mandatory teaching of African culture according to Law 10.639/03, its presence in Brazilian schools is still limited and faces several challenges, such as prejudice and stereotypes, isolated practices on specific dates to meet protocols, and teachers' insufficient undergraduate education on this topic. In this context, it becomes relevant to investigate teachers' self-efficacy beliefs regarding the teaching of these contents. Teacher self-efficacy is defined as the judgment that teachers make about their ability to establish teaching strategies, create effective learning environments, and engage students even in the face of difficulties. Thus, teachers' confidence in their ability to teach African culture can directly influence their practices with this content in the school routine. This study aimed to investigate the relationship between teachers' perceptions of the influence of the school environment, their literacy in African culture, and their self-efficacy beliefs to teach this content in physical education classes. The study was exploratory and used a quali-quantitative approach. A questionnaire with a 0-10 scale was applied to assess teachers' perceptions of the influence of the school environment, literacy in African culture, and self-efficacy beliefs. For the study, the essential knowledge required for teaching African culture in physical education classes was defined, taking into account the legal framework, curriculum guidelines, and official documents in Brazilian education. Based on this knowledge, the specific domains for teaching African culture were identified, analyzing the diversity of content and knowledge dimensions (conceptual, procedural, and attitudinal). The results indicated that, although teachers reported a high perception of self-efficacy in topics such as combating racism and African-based games and play, this perception did not extend to topics such as African history and culture, African martial arts, and dances. Additionally, the findings showed that the higher the perception of literacy, the more favorable the school environment was perceived to be for teaching African culture, and the greater the self-efficacy in teaching this content. It was also found that internal factors related to personal moral agency tend to be more effective motivators than external regulators such as laws, curriculum guidelines, and official documents. Based on the results, the study highlights the need for racial and cultural literacy in teacher education to promote a more meaningful approach to this theme within the school curriculum, thereby enhancing self-efficacy beliefs for teaching this content in physical education classes.
O teletrabalho e a gaiola de silício: autonomia, controle e resistência no contexto da pandemia de Covid-19
(Universidade Federal de São Carlos, 2025-03-27)
Veloso, Braian Garrito
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Lima, Jacob Carlos
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https://lattes.cnpq.br/9244132532446607
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https://orcid.org/0000-0001-6475-9575
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https://lattes.cnpq.br/2537302046587655
This research has, as a general objective, to analyze the trends in new processes of technification of contemporary life revealed from the experience of transition from face-to-face work to teleworking in the context of the Covid-19 pandemic. We start from the hypothesis that this experience of change is fertile ground for observing the main characteristics that involve the relationships between workers and digital technologies within a specific historical-social framework that, in this thesis, we defend based on the original concept called silicon cage. The specific objectives are: to describe and define the characteristics of teleworking, considering its specificities in the context of the Covid-19 pandemic; identify the objective conditions of teleworking in the context of the pandemic and beyond of it; understand the relationship between workers and digital technologies and the resulting implications; investigate changes from face-to-face work to teleworking based on modulations of time, space and subjective engagement in light of the perception and experience of autonomy; and explain the transition from the iron cage to the silicon cage. When it comes to methodology, it is a qualitative approach that included convenience sampling. The study starts from a phenomenological perspective in that it emphasizes the subjects' experience and their perceptions. Regarding methodological procedures, we used: narrative bibliographic review, virtual questionnaire and semi-structured interviews. Based on some of the main results, it was observed that, in the pandemic, the relationship between workers and technologies involved, in some cases, important resignifications in the ways in which subjects understand digital technological resources; the experiences of teleworkers during the pandemic are also related to previous objective conditions; modulations in teleworking, when combining time and space, tend to promote overload situations; and the use of mobile technologies contributes to the configuration of what we call the silicon cage as a process of technification of contemporary life.
Modelo matemático e computacional para robôs espaciais de base livre e múltiplos braços com momento não-conservado
(Universidade Federal de São Carlos, 2025-03-27)
Rodrigues, Gabriel da Silva
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Pazelli, Tatiana de Figueiredo Pereira Alves Taveira
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https://lattes.cnpq.br/2574900514697052
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https://lattes.cnpq.br/9268113350374242
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Siqueira, Adriano Almeida Gonçalves
The development of orbital space robotics in recent decades is aimed at meeting the demand for extra-vehicular missions, such as supply, maintenance, inspection, rescue and transport of materials. A space manipulator can be defined by one or more arms attached to a floating base (satellite) designed for operation in orbit. The distinguishing characteristic of these systems is the dynamic coupling between the base and the manipulators. In this work, a mathematical model is proposed for a space robot with multiple arms and a floating base, capable of dealing with external forces and non-zero linear and angular momentum, especially to maximize the fidelity between the model and the robot in detumbling applications. The main objective is to present a mathematical model that is sufficiently detailed in the constructions of vectors and matrices necessary for its implementation, maintaining its functional generality and consistency with the real operation of the manipulator in terms of obedience to the laws of classical mechanics. The work in question addresses gaps in the literature regarding the dynamic model in Cartesian space and the behavior of the robotic system in conditions of interaction with non-cooperative targets, such as inconsistencies in the calculations of non-inertial terms and angular momentum, mapping of forces between joint and task domains through the Generalized Jacobian Matrix and cancellation of momentum in post-impact situations. From simulations, it is clear that the presented formulations are internally consistent in joint and inertial domains. The application of multiple target stabilization tasks, whose formulation is based on the generalization of the spatial Jacobian for multiple arms, presented satisfactory performance, thus assuming a relevant role in future applications involving multiple target detumbling.
Professores da UFT no ensino remoto: caracterização da sociedade de risco e análise do espaço-tempo pela teoria ator-rede
(Universidade Federal de São Carlos, 2025-03-27)
Silva, Maria Emília da
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Vilela, Denise Silva
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https://lattes.cnpq.br/8155152145332951
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https://lattes.cnpq.br/2243534212480178
Contemporary society has witnessed the evolution of digital technologies in a wide range of sectors. In the field of education new ways of teaching and learning using these tools are also being experienced or discussed. In the years 2020/2021, we experienced a pandemic caused by the Sars-CoV-2 virus and, to face this situation, in schools and universities there was emergency remote teaching. In this thesis, the sociotechnical network that configured emergency remote teaching in higher education at the Federal University of Tocantins (UFT) at the Arraias/TO campus during the aforementioned period was investigated.This is a qualitative research, with field research, through interviews with thirteen professors from the five in-person undergraduate courses at this university. The main objective was to characterize emergency remote teaching as part of the risk society as defined by Ulrich Beck. We also used Bruno Latour's Actor-Network Theory (ANT) to understand the space and time that were performed in this sociotechnical network, highlighting deviations, compositions, and networks. The expression globalization-minus, defined by Latour (2020) to identify situations in times of crisis, will also be used. The main results were: TAR provided us with another bias in the perception of the sociotechnical network that involved space and time in emergency remote teaching, in which it deepened the understanding of the sociotechnical networks involved, examining how space, time, actors and practices were incessantly formed and negotiated. It was found that a situation of immediacy was performed on the part of students when it came to obtaining feedback from teachers; the issue of delays in synchronous meetings was perceived differently from in-person teaching. The connections between remote teaching and science, technology, politics, society, health and education became more visible. Regarding the risk society, it was evident that this period was very complex, bringing to light anguish, stress, insecurities, anxieties and a lot of uncertainty, by the interviewees in this unprecedented situation, due to the speed of decision-making in an uncertain scenario. The sketches of the networks also show the unprecedented scenario that was performed in this teaching.
Análise multivariada de conteúdos da cultura científica via ciência de dados sociais e aprendizado de máquina RAG-LLM (geração aumentada por recuperação para modelos linguísticos de grande dimensão)
(Universidade Federal de São Carlos, 2025-03-28)
Terezan de Moura, Renato Aparecido
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Sousa, Cidoval Morais de
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https://lattes.cnpq.br/0573233540937425
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https://orcid.org/0000-0002-7812-8667
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https://lattes.cnpq.br/9976994758941814
Guided by interdisciplinary epistemological approaches from the field of Science, Technology, and Society (CTS), we investigated communication dynamics in two projects at a public university, using a hybrid approach that combines Content Analysis with Machine Learning and Social Data Science. We collected and analyzed collections from websites and digital media, including interactions in chats, comments, and event broadcasts. Our research demonstrated the effectiveness of scientific culture dynamics, the public reach of the projects, and revealed user idiosyncrasies through the correlation of quantitative and qualitative variables. The data was collected and mined using statistical and Natural Language Processing (NLP) techniques in MAXQDA software, and complemented by multivariate analyses. To analyze audiovisual and textual content from streaming channels, we developed machine learning pipelines with RAGs-LLMs (Retrieval-Augmented Generation for Large Language Models). The results of the thesis are presented in visual and analytical dashboards on the website tecnociencia.net.br, where we also implemented a conversational robot (Tesebot), trained with the research content to answer questions. The conclusion of the thesis shows that its corroboration is inevitable and loaded with statistical and inferential certainties, which reflect and legitimize the complexity of research in the era of post-academic science, big tech, social networks, and artificial intelligence. The methodological strategies made it possible to understand all the variables and statistical and relational instances involved in the dynamic observation of scientific culture in the dissemination projects researched.
Produção de nanoestruturas de carbono para bioaplicações
(Universidade Federal de São Carlos, 2025-03-28)
Almeida, Larissa Solano de
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Viana Neto, Bartolomeu Cruz
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https://lattes.cnpq.br/2504557482950231
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https://orcid.org/0000-0002-5207-4269
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Rossino, Luciana Sgarbi
Carbon nanotubes (CNTs) stand out in research due to their attractive chemical and physical properties, which are influenced by the high quality of these nanostructures and allow their application in several areas. The quality of CNTs is directly related to growth parameters, such as gas flow, voltage, time, and temperature. Conventional techniques, such as chemical vapor deposition (CVD), produce carbon nanostructures with fewer defects but require high temperatures, reaching 1000 °C. A promising alternative is plasma-assisted chemical vapor deposition (PECVD), capable of producing CNTs at temperatures close to 450 °C. This work aimed to obtain CNTs through the PECVD technique with a pulsed DC source. The growth was performed on a nickel substrate, using Ar/H₂/CH₄ gases, with a voltage of 500 to 800 V, temperature of approximately 450 °C, and treatment times ranging from 5 to 30 minutes. The discovered nanostructures were recorded by Raman spectroscopy, SEM, TEM, XPS, fixed-sphere wear test, UV-Vis scattering test, and cytotoxicity and toxicity tests in terrestrial and aquatic environments. The Raman spectra revealed bands characteristic of carbon-based materials, such as D, G, D’, 2D, and D+G. For effective growth, the plasma needed to have sufficient energy, and the SEM micrographs confirmed the effective formation of CNTs at resistances above 700 V. The growth time directly influenced the quantity and quality of CNTs, with greater production observed in periods longer than 15 minutes. The diameter of the CNTs increased with the increase in the total gas flow. The results indicated the delivery of multi-walled carbon nanotubes (MWCNTs), with the presence of defects, which may be advantageous depending on the application. The optimized growth settings were: flow rate of 235 sccm, voltage of 800 V, and time of 30 minutes, producing MWCNTs effectively. Furthermore, with the optimized settings, it was possible to evaluate the incorporation of nitrogen on the surface of the CNTs. The results demonstrated that the increase in the nitrogen flow caused greater structural disorder, indicating its incorporation. The CNTs presented greater dispersivity in an aqueous medium compared to CNTs with nitrogen and commercial CNTs. Furthermore, the CNTs demonstrated lower toxicity in biological, terrestrial, and aquatic systems, being promising for bioapplications. As a second work proposal, the production of a CNTs/DLC hybrid carbon nanostructure was carried out, evaluating its tribological potential. The material presented wear resistance, showing significant potential due to the synergy between the properties of CNTs and DLC films. However, further studies and characterization techniques are needed to validate these results. Thus, the work highlights the importance of optimizing growth parameters to obtain quality and quantity of CNTs at low temperatures using the PECVD technique.
Desenvolvimento e validação de método analítico para determinação de nutrientes e contaminantes em pescados do baixo rio São Francisco utilizando técnicas de plasma
(Universidade Federal de São Carlos, 2025-03-28)
Silva, Lorena Lima da
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Nogueira, Ana Rita de Araújo
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https://lattes.cnpq.br/7034773971317045
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https://orcid.org/0000-0003-3648-2956
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https://lattes.cnpq.br/1923563841127712
DEVELOPMENT AND VALIDATION OF AN ANALYTICAL METHOD FOR DETERMINING NUTRIENTS AND CONTAMINANTS IN FISH FROM THE LOWER SÃO FRANCISCO RIVER USING PLASMA TECHNIQUES. The Lower São Francisco (BSF) region, which includes areas of Alagoas, Sergipe, Bahia, and Pernambuco, plays an essential role in socioeconomic development and the preservation of local culture. However, the impacts arising from human activities can cause the bioaccumulation of harmful substances, such as potentially toxic elements, in aquatic organisms and biomagnification along the food chain. Monitoring water parameters of ichthyofauna and flora is essential to assess environmental impacts, identify reliable bioindicators, ensure food security, and support sustainable management policies. This study developed and validated an analytical methodology suitable for the determination of nutrients and inorganic contaminants in fish collected in the BSF by microwave-induced plasma optical emission spectrometry (MIP OES) and inductively coupled plasma mass spectrometry (ICP-MS). The optimal digestion and determination conditions were established, which included the determination of the limits of detection (LOD), quantification (LOQ), linearity, precision, and accuracy, using certified reference materials and addition and recovery assays. Iron, Zn, Cr, Cu, V, Ni, Co, Mo, Mn, Se, Sr, As, Cd, Hg, and P were determined by ICP-MS and Ca, K, Mg and P by MIP OES in 136 samples collected in two stations, over 12 months. The Pb, Ni, Mo, Cd, Cr, Co, and V levels were < LOD in all samples evaluated. For the summer, the determined contents indicated the following variations: Ca (0.1−2.8 g kg⁻¹), K (1−8 g kg⁻¹), Mg (0.1−0.6 g kg⁻¹), P (0.6−5 g kg⁻¹), Fe (0.7−15 mg kg⁻¹), Zn (0.9−12 mg kg⁻¹), Se (0.1−0.6 mg kg⁻¹), Sr (0.1−5 mg kg⁻¹), Cu (0.1−9.2 mg kg⁻¹), Mn (0.1−2 mg kg⁻¹) and As (0.1−5 mg kg⁻¹). For winter, Ca (0.1−2 g kg⁻¹), K (1−7 g kg⁻¹), Mg (0.2−0.4 g kg⁻¹), P (0.5−5 g kg⁻¹), Fe (0.3−10 mg kg⁻¹), Zn (0.4−20 mg kg⁻¹), Se (0.1−0.6 mg kg⁻¹), Sr (0.1−6 mg kg⁻¹), Mn (0.1−3 mg kg⁻¹), As (0.1−4 mg kg⁻¹) and Cu (0.1−0.3 mg kg⁻¹). For the first time, the mineral profile of BSF fish was obtained, indicating satisfactory nutrient levels per the daily consumption recommendations and contaminants below the limits established by legislation.
Análise funcional da atenção compartilhada em bebês com deficiência visual: uma replicação
(Universidade Federal de São Carlos, 2025-03-28)
Silva, Thalissa Cazarine da
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Gil, Maria Stella Coutinho de Alcântara
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https://lattes.cnpq.br/1673770301699940
;
https://orcid.org/0000-0003-4375-3232
;
Latina
Joint Attention (JA) is a triadic process essential for child development, involving the coordination of attention between the infant, an adult, and an event or object. Although traditionally associated with behaviors such as eye contact and pointing, this model becomes limited when applied to infants with visual impairments (VI), who may develop alternative forms of social and cognitive engagement. Despite its relevance, there is a scarcity of studies that examine JA from a behavior-analytic perspective, especially in the context of VI. This study aimed to conduct a descriptive functional analysis of the contingencies that support JA in dyads composed of a sighted adult and a child with VI, aged between 10 and 36 months. Interactions were video-recorded in a structured environment using tasks adapted from the Early Social Communication Scales (ESCS). Video logging enabled the identification of discriminative stimuli, dyadic responses, and the consequences that maintained episodes of JA. Results showed that the adult’s Requesting Speech (RS) and Descriptive Speech (DS) functioned as effective discriminative stimuli for evoking JA responses in infants. Additionally, auditory and luminous stimuli significantly increased the frequency of JA episodes, whereas tasks relying solely on distant visual stimuli led to reduced engagement. The physical proximity of the stimulus also favored the occurrence of JA, although the presence of auditory cues proved more decisive in regulating infant responsivity. Another key finding was the predominance of adult-initiated JA attempts (IJA), which were not always followed by infant responses (RJA). This highlights the need for a contingent and temporally contiguous relationship between IJA and RJA to configure a functional episode of joint attention. These findings offer valuable insights for educational and intervention strategies in the field of Special Education, helping professionals and families foster more responsive and functional interactions. It is recommended that future research develop teaching procedures to expand the IJA and RJA repertoires of infants with VI, as well as parental training programs aimed at enhancing caregivers’ sensitivity in mediating access to discriminative stimuli. The results of this study suggest that infants with visual impairments can learn to engage in joint attention, provided that social interactions are designed in accordance with their sensory limitations and developmental potential.
Impactos de complexos de rutênio (II) em diferentes abordagens da agregação do peptídeo beta amiloide
(Universidade Federal de São Carlos, 2025-03-28)
Tiburcio, Marco Antonio
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Carlos, Rose Maria
;
https://lattes.cnpq.br/1589143355309943
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https://orcid.org/0000-0002-0277-9789
;
https://lattes.cnpq.br/0990167626370741
Alzheimer's Disease is the most common form of dementia, with projected costs of $1 trillion by 2030. Its main features include deposits of the Aβ peptide and neurofibrillary tangles of the tau protein. Increased life expectancy is linked to the rising incidence of the disease, creating significant social and financial impacts. This study aims to evaluate the effects of Ru(II) complexes as modulators of Aβ aggregation in different approaches, from heterogeneous aggregation with insulin to in vivo applications. The modulating effect of the RuApy complex on cross-aggregation between Aβ and insulin was monitored through Tyr10 emission, circular dichroism (CD), and AFM. Emission spectra for Aβ showed suppression of Tyr-OH emission (300 nm) in favor of Tyr-O¯ ion formation (340 nm), a behavior not observed in the presence of insulin and the RuApy complex. CD and AFM analyses revealed the formation of amorphous aggregates instead of the fibrils typically seen with Aβ. The aggregates formed in the Aβ/Insulin and Aβ/Insulin/RuApy interactions were less toxic compared to Aβ aggregates when tested on SH-SY5Y neuroblastoma cells. In another approach, the influence of the RuNDI complex on Aβ aggregation was monitored by nephelometry, CD, and TEM. The presence of the RuNDI complex significantly reduced relative nephelometry units and suppressed β-sheet signals in CD spectra, indicating reduced aggregate formation. TEM images revealed the formation of amorphous aggregates. The effects of the RuNDI complex on Aβ aggregation were also evaluated in APP/PS1 mice, a model for Alzheimer's Disease. These animals develop Aβ deposits in the cortex and hippocampus after 16 weeks of age. The complex was administered intraperitoneally at daily doses of 1 mg/kg for 10 weeks. Amyloid deposition was monitored in real-time using multiphoton microscopy. ELISA and immunofluorescence assays were performed on blood and cortex samples at the end of the experiments. Although real-time disease progression could not be assessed, lower levels of Aβ40/42 were observed in cortex samples from treated mice. Immunofluorescence using ThS and 4G8 showed that the RuNDI complex did not affect the size of existing plaques but significantly reduced plaque density and load in the cortex and hippocampus. These observations demonstrate that the RuApy and RuNDI complexes directly impact Aβ fibrillation in different approaches, leading to the formation of amorphous and non-toxic fibrils and reducing the formation of deposits in critical brain areas of transgenic mice.
Efeitos do exercício físico na destreza manual, sintomas motores e plasticidade cerebral em indivíduos com doença de Parkinson
(Universidade Federal de São Carlos, 2025-03-28)
Menacho, Maryela Oliveira
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Gianlorenço, Anna Carolyna Lepesteur
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Fregni, Felipe
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https://lattes.cnpq.br/3861050459671690
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https://lattes.cnpq.br/7140517621736868
Parkinson’s disease is the second most common progressive neurodegenerative disorder and is characterized by symptoms such as resting tremor, bradykinesia, rigidity, and postural instability, which significantly affect upper limb function in patients. Physical exercise is a non-pharmacological intervention alternative for these patients, as it can contribute significantly to improving quality of life. Therefore, this thesis was divided into two studies. The first aimed to gather the available literature on the effects of physical exercise on upper limb function in individuals with Parkinson’s disease through a systematic review. A systematic search was conducted using the PubMed, Embase, CENTRAL, PEDro, Scopus, and Web of Science databases, including the following terms: Parkinson’s disease, exercise/physical therapy, upper limb, and their respective entry terms. These terms were combined using Boolean operators (AND/OR) according to each database. A total of 15 randomized controlled trials were included, which performed the following interventions: task-oriented training, virtual reality/game therapy, training of activities of daily living, robotic therapy, training with a musical instrument, eccentric strengthening, constraint-induced movement therapy, manual dexterity training, and exercises with therapeutic mass. In conclusion, activity-based training is a viable option to improve manual dexterity in individuals with Parkinson’s disease. The second study was a randomized controlled clinical trial aimed at evaluating and comparing the effects of different physical intervention modalities—aerobic training, resistance training, and task specific training on motor symptoms, manual dexterity, and brain oscillatory activity in individuals with Parkinson’s disease. Thirty-seven participants, with a mean age of 62 years and presenting upper limb functional deficits, completed the study. Participants were randomized into four groups: aerobic training (AT), resistance training (RT), task specific training (TT), and control group (CG). The AT group performed 30 minutes of upper limb cycling using a portable cycle ergometer at an intensity of 50–70% of heart rate reserve. The RT group performed two sets of 8 to 12 repetitions for each exercise, with a two-minute rest between sets, at an intensity of 50–70% of one-repetition maximum (1-RM), determined by the 1-RM test. Free weights and an upper limb exercise machine were used for the resistance exercises. The TT group performed three activities aimed at improving reach, grasp, and manipulation for 30 minutes. All intervention sessions were conducted three times per week for eight weeks. Motor symptoms were assessed using part III of the Unified Parkinson’s Disease Rating Scale (UPDRS-III). Manual dexterity was evaluated using the Nine-Hole Peg Test, and quantitative electroencephalography (qEEG) was used to assess brain activity. Two-way ANOVA and the Scheirer–Ray–Hare test were used to evaluate the effects of time and group on clinical variables, and group and brain region on EEG band power. The level of statistical significance was set at 5%. There was a significant main effect of time (F = 2.80; p = 0.05) and group (F = 2.94; p = 0.03) on the UPDRS-III, with no significant interaction between the factors (F = 1.46; p = 0.23). Tukey's post hoc test showed significant differences in the aerobic (p = 0.04) and resistance training groups (p = 0.04) compared to the control group. No significant group (F = 0.54; p = 0.70) or time effect (F = 0.87; p = 0.35) was observed in the Nine-Hole Peg Test. Additionally, the interventions had a significant effect on the low-alpha sub-band (F = 4.85; p = 0.003) and the alpha band (F = 5.10; p = 0.003), regardless of brain region, in the task specific training group compared to the control group (p = 0.001). For the beta band and low-beta sub-band, there was a main effect of the interventions (F = 5.56; p = 0.001) and (F = 7.59; p < 0.001), with no effect of brain region and no interaction between factors. Tukey's post hoc analysis revealed a significant difference in low-beta in the task specific training group compared to the control group (p < 0.001), and in beta for the resistance training (p = 0.007), aerobic training (p = 0.008), and task specific training (p = 0.004) groups compared to the control group. In conclusion, task specific training based on activities of daily living significantly improved motor symptoms and reduced alpha, low-alpha and low-beta spectral power in individuals with Parkinson’s disease. Furthermore, all interventions caused a significant reduction in beta spectral power, with no difference between them and regardless of brain region. Therefore, the studies presented in this thesis support the importance of physical exercise as a non-pharmacological strategy within the therapeutic plan for this population. In the systematic review, the meta-analysis showed a significant effect of activity-based training on fine manual dexterity compared to other active interventions, while the clinical trial demonstrated a significant improvement in motor symptoms among those who received either aerobic or resistance training. Finally, all proposed interventions resulted in significant changes in brain oscillatory activity.
Análise multidimensional dos componentes edáfico e arbóreo em sistemas integrados de produção
(Universidade Federal de São Carlos, 2025-03-28)
Fernandes, Pedro Henrique de Godoy
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Bernardi, Alberto Carlos de Campos
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https://lattes.cnpq.br/5588269274851789
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Tanaka, Marcel Okamoto
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https://lattes.cnpq.br/2768658925977757
The increasing global demand for food drives deforestation of natural areas, converting them into agricultural and livestock production systems, thereby increasing greenhouse gas (GHG) emissions and accelerating ongoing climate change. Therefore, production models that reconcile food production with environmental conservation need to be implemented. This study evaluated integrated crop-livestock-forestry (ICLF) and livestock-forestry (ILF) systems, as well as forest restoration, as land use strategies to improve improve soil chemical and physical parameters and mitigate GHG emissions. Additionally, a methodology for monitoring forest metrics through remote sensing was assessed. The first chapter evaluated the physical and chemical attributes of soil in ICLF, ILF, forest restoration, degraded pasture, and forest remnants. We observed that systems incorporating a tree component improved soil quality by increasing organic matter (OM), cation exchange capacity (CEC), carbon content (C), and reducing soil bulk density. In the second chapter, we analyzed forest structure, as well as soil and aboveground biomass (AGB) carbon stocks, in areas under ICLF, ILF, forest restoration, and forest remnants. Integrated systems exhibited larger trees with lower stratification, whereas restoration and forest remnants showed higher tree density, greater stratification, and higher basal area. AGB C stocks were similar across areas, except for ICLF-N and ICLF-G. Forest remnants and ILF systems had the highest soil carbon stocks. Total C stocks were comparable among ILF, restoration, and forest remnants, with approximately 60% stored in the soil and 40% in AGB. The third chapter involved the validation of remotely piloted aircraft (RPA) and digital aerial photogrammetry (DAP) for estimating forest metrics. Field data on diameter at breast height (DBH), tree height, basal area, tree density, and AGB were compared with three-dimensional models generated from orthomosaics and point clouds, using multiple linear regression models. After model selection, we spatialized the variables of interest across the entire study area. The digital terrain model accurately represented the area's topography, contributing to model quality. The predictive model for DBH showed the lowest R² along with the lowest RMSE, while the height model performed slightly better. Basal area and tree density yielded similar results. The predictive model for AGB demonstrated satisfactory R² and RMSE values for estimating AGB and forest metrics. Therefore, integrated production systems contribute to soil quality and C stocks. Systems such as ICLF and ILF, along with forest restoration, are capable of sequestering amounts of C from AGB comparable to those in forest remnants, making them effective strategies for GHG’s emission mitigation. Lastly, we found that DAP-related methods can be applied in integrated production systems, facilitating better access to carbon stock estimates and monitoring for rural producers.
Modificação estrutural do Nb2O5 para aplicação em processos de remediação ambiental
(Universidade Federal de São Carlos, 2025-03-28)
Rodrigues, Thaís Aparecida
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Mendonça, Vagner Romito de
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https://lattes.cnpq.br/4270375873948823
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https://lattes.cnpq.br/3891783906198938
Brazil holds 98 % of the world’s niobium deposits, making it essential to add scientific and economic value to this material. This study investigated the modification of niobium pentoxide with other oxides, specifically vanadium pentoxide and tungsten trioxide, using the oxidative peroxide method followed by hydrothermal treatment, to enhance its photocatalytic and adsorptive properties for environmental remediation applications. The synthesized samples were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), N2 physisorption-desorption, and zeta potential analysis. The photocatalytic and adsorptive properties were evaluated through the photodegradation and adsorption of dyes Methylene Blue (MB) and Rhodamine B (RhB), the pharmaceutical Amiloride (AML), and the CO2 photoreduction process. For the vanadium-based modification, ammonium niobium oxalate (ANO) was used as a precursor. However, due to changes observed in the material over time, the experiments were conducted in two separate stages, using ANO from the 2017 and 2022 batches. In both cases, the analyses confirmed the doping of Nb2O5 with vanadium. Under the first condition (2017 batch), the doped sample exhibited excellent performance in the photodegradation of RhB and AML compared to isolated Nb2O5. In the CO2 photoreduction tests, the vanadium-modified sample favored CO formation over H2, suggesting that the modification enhanced CO2 adsorption on the material’s surface. Under the second condition (2022 batch), the modification improved the adsorptive properties of MB. Adsorption studies indicated that the primary adsorption mechanism was physisorption, and the sample maintained its efficiency over five consecutive cycles. For the modification of Nb2O5 with WO3, the optimal condition was achieved using ammonium niobium oxalate and tungstic acid, with a molar ratio of 80% WO3 to Nb2O5. The analyses confirmed the formation of a heterostructure. In the photodegradation tests, the heterostructure exhibited combined properties of both oxides, as bare Nb2O5 and WO3 were more effective in decolorizing MB and RhB, respectively. However, the heterojunction was capable of both adsorbing and photodegrading both dyes. The results indicate that modifying Nb2O5 with vanadium and tungsten compounds enhanced its photocatalytic and adsorptive properties, making these materials promising for environmental remediation applications.
Direito à água: contribuições para o acesso mais justo, equitativo e democrático à água
(Universidade Federal de São Carlos, 2025-03-31)
Moraes, Tatiana Vieira de
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Oliveira, Celso Maran de
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https://lattes.cnpq.br/9911833172043700
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https://orcid.org/0000-0002-6442-3614
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https://lattes.cnpq.br/3999527499047171
Water in quantity and quality is an essential human right, but a large portion of the population still does not have access to this right. SDG 6 sets the goal of universal and equitable access to water for all people by 2030 and, based on the hypothesis that the current Brazilian water management system does not sufficiently guarantee access to the right to water in an equitable and fair manner, this study aims to identify, based on case studies of water conflicts, various possibilities and potential actions, measures or principles with a view to contributing to fairer, more equitable and democratic access to the right to water. To this end, methodological pluralism was adopted, with each chapter addressing a set of specific methods and procedures. The study is presented in three parts: the first, more theoretical, proposes a literature review. At this point, the right to access water as an essential human right is discussed, pointing out the possibility of considering water as a fundamental right in Brazil, even without express constitutional provision. It also analyzes the Brazilian National Water Resources Policy and criticizes the conventional model of water resources management adopted in Brazil, especially its limitations in terms of participation and equity. This is followed by a discussion of effective water governance, highlighting the importance of a governance system that strengthens the participation of society. This part of the study concludes with theoretical clarifications on the concept of water equity, presenting definitions and basic elements, as well as differentiating equity from water justice. The second part examines case studies of water problems/conflicts. Adopting a narrow geographical approach, a survey was carried out of cases of international and national water conflicts in the literature; in the state of São Paulo through Civil Inquiries by the Public Prosecutor’s Office of São Paulo (MPSP); and a local case in the municipality of São Carlos/SP. The results of this part of the study were the mapping of water conflicts based on the cases examined and the potential of the measures and solutions suggested and/or applied to resolve or mitigate the conflicts. The third part of the study is propositional, presenting contributions to more equitable and democratic access to the right to water and interconnecting the first two parts. The analyses of the previous parts of the study demonstrate the existence of various inequalities in access to water and the inadequacy of the conventional water management system to sufficiently guarantee fair, democratic and equitable access to the right to water. As a result, contributory proposals were generated aimed at advancing the transition from the current water management format to a more effective system of ‘good water governance’ that promotes democratic, equitable and fair access to the right to water.
Fusão em leito de pó a laser de aço ferramenta A2: efeito de parâmetros de processo, tratamentos térmicos e adição de Cr₃C₂
(Universidade Federal de São Carlos, 2025-03-31)
Bianchini, Bruno
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Gargarella, Piter
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https://lattes.cnpq.br/4641435644243916
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https://orcid.org/0000-0003-4445-5819
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https://lattes.cnpq.br/8443988120967281
Tool steels have strict requirements for composition, processing and mechanical properties, and are utilized in fabrication of molds or tools employed in the processing of other materials. In many cases, they are expensive and of difficult machinability, which opens up the possibility for alternative processing routes such as additive manufacturing (AM) by Laser Powder Bed Fusion (L-PBF), which allows fabrication of parts with complex sections, such as internal cooling channels, without additional processing cost and with minimal need for post-processing, due to its great dimensional accuracy. However, the severe conditions to which the L-PBF process submits materials induce the formation of a highly refined microstructure, and possibly defects. This work studies the possibility of manufacturing AISI A2 tool steel by L-PBF, considering the effect of process parameters and post-processing in its microstructure and properties, and the modification of this material for defect mitigation. Results showed that, despite it being possible to determine a processing window for minimal porosity, the material composition and the severe processing conditions cause the formation of cracks, mostly during solidification. The as-built microstructure is, similarly to other tool steels manufactured by L-PBF, composed of martensite cells surrounded by retained austenite, while the formation of primary carbides is suppressed. After heat treatment, the formation of secondary carbides was found to be also in low quantity, showing that temperings without prior austenitization would need higher temperatures or longer times to cause significant effects on the microstructure and mechanical properties. Finally, it was discovered that the addition of Cr3C2 chromium carbide by mechanical mixture, at a fraction of 5%, was capable of mitigating defect formation by altering the alloy composition, when manufactured by L-PBF.
Feijão guandu para uso alimentar: composição química, funcionalidade e aspectos nutricionais
(Universidade Federal de São Carlos, 2025-03-31)
Tozo, Marcelo Larsen de Lima
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Rita de Araujo Nogueira, Ana
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https://lattes.cnpq.br/7034773971317045
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https://orcid.org/0000-0003-3648-2956
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https://lattes.cnpq.br/6205481423806854
This dissertation aims to develop and apply analytical procedures to evaluate the total levels, bioaccessibility, and bioavailability of essential elements and total proteins in two pigeon pea (Cajanus cajan (L.) Millsp) varieties previously selected for human consumption. Raw and cooked samples were evaluated at different stages of maturation, as well as commercial varieties of common beans (carioca and black). Bioaccessibility and bioavailability were obtained after in vitro gastrointestinal digestion simulations and bioassays with Caco-2 cells. For proteins, the total fraction and the bioaccessible fraction were quantified by combustion (Dumas), and free amino acids by high-performance liquid chromatography (HPLC). The macro and micronutrients evaluated, Ca, Mg, P, Cu, Fe, and Zn, were determined by inductively coupled plasma optical emission spectrometry and mass spectrometry (ICP OES and ICP-MS), after microwave-assisted decomposition using diluted acid (7.0 mol L-1), both for total contents and for bioaccessible and bioavailable fractions. The bioaccessibility of elements varied from 0.8 to 19% for Ca and from 48 to 67% for Cu. Bioaccessibility of Ca, Fe, Mg, and Zn decreased with bean maturation. Finally, an in vitro intestinal simulation with Caco-2 cells, aimed at estimating nutrient bioavailability, faced issues with the integrity of the cell monolayer, making it impossible to estimate bioavailability values. However, the results obtained suggest the direction to be followed for improving this experiment and obtaining reliable results. Regarding crude protein content, pigeon pea samples were close to 20%. For amino acids, amounts ≥ 1% of glutamic acid, aspartic acid, and leucine were found. For the mature grain, lysine and phenylalanine were present in amounts ≥ 1%, compared to the green grain. However, in the mature grain, the amounts of glycine, histidine, threonine, alanine, and tyrosine were low (≤ 0.4%), and no methionine, cystine, or taurine were detected in either grain. The protein bioaccessibility varied between 16.4% and 19.4%. There was an increase in the total protein content with the maturation of the beans, while the bioaccessible percentage remained unchanged. For the recommended daily intake (RDI), the consumption of 100 g of cooked food suggests that the pigeon pea may be an alternative source of nutrients, highlighting Mg and P, although its contribution is lower compared to the commercial varieties of carioca and black beans. Additionally, all the beans studied show potential for protein supplementation, ranging from 32.8 – 38.8% of the RDI, reinforcing the importance of these legumes and others in human nutrition.This study is significant from a nutritional perspective, providing unprecedented data on the nutritional aspects of two varieties of pigeon peas and the bioaccessibility of essential elements, indicating their use as a consumption alternative.
Modelagem multiescala e validação experimental da dinâmica interfacial em sistemas de eletrólise da água: explorando fenômenos locais inerentes das reações eletroquímicas
(Universidade Federal de São Carlos, 2025-03-31)
Leite, Gabriel Wosiak
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Souza, Ernesto Chaves Pereira de
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https://lattes.cnpq.br/1505400360366643
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https://orcid.org/0000-0003-1058-302X
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https://lattes.cnpq.br/8033550667466489
This thesis addresses the efficiency challenges in hydrogen production via water electrolysis, focusing on the coupled effects of gas bubble evolution and interfacial pH variations during alkaline electrolysis. Multiscale computational models were developed, combining the Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) to simulate bubble dynamics and interfacial pH distribution, with experimental validation using filming techniques and chronopotentiometric analysis to explore energy consumption during electrolysis. The results showed that pulsed-current operation can mitigate local pH variations; however, maintaining stable pH conditions under high current densities remains a challenge. Additionally, an asymmetric electrolysis cell configuration was proposed and validated, demonstrating a reduction in local pH gradients and up to a 17% improvement in electrolysis efficiency. This work opens new perspectives for developing more efficient electrolyzers, contributing to sustainable and economically viable hydrogen production.
Como a alfabetização científica se desenvolve no contexto da educação básica: um olhar sobre a prática docente
(Universidade Federal de São Carlos, 2025-03-31)
Stranghetti, Natalia
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Marques, Clelia Mara de Paula
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https://lattes.cnpq.br/0451284088402660
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Venâncio, Tiago
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https://lattes.cnpq.br/4438399441102990
This study aimed to analyze the presence and development of Scientific Literacy (SC) in Basic Education, highlighting its relevance as an essential tool for understanding and applying scientific knowledge in everyday life and in the modern world. To this end, Chemistry classes were monitored in two state schools, seeking to identify the presence of SC in basic education. In addition, the teachers of these classes were interviewed, allowing a qualitative analysis based on the principles of Bardin's Content Analysis. Initially, SC indicators observed during classes were collected, while categories were created for essential aspects that did not appear, but are fundamental for the development of SC in education. In order to deepen the investigation, interviews were conducted with other teachers from the state network to understand their perceptions about SC. The research also included the analysis of legislation and documents guiding education in Brazil, such as the National Common Curricular Base (BNCC) and the Law of Guidelines and Bases of National Education, in order to verify how SC is addressed in curricula and pedagogical guidelines. The results indicated that CA is present in Basic Education, but there is a vast potential that has not yet been explored, since several essential parameters were not identified in the observed teaching practice. The study suggests that CA could be significantly more stimulated if there were greater awareness and guidance among education professionals about its importance. In addition to the lack of specific knowledge, it was found that the limited time allocated to the study of teaching tools and methods compromises the development of pedagogical practices that facilitate the learning and understanding of scientific content.