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Produção de nanoestruturas de carbono para bioaplicações
(Universidade Federal de São Carlos, 2025-03-28) Almeida, Larissa Solano de; Viana Neto, Bartolomeu Cruz; https://lattes.cnpq.br/2504557482950231; https://orcid.org/0000-0002-5207-4269; Rossino, Luciana Sgarbi; https://lattes.cnpq.br/0139027055418391; https://orcid.org/0000-0003-2755-8349; https://lattes.cnpq.br/6673871313645316; https://orcid.org/0000-0001-6858-1524
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.
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; Gianlorenço, Anna Carolyna Lepesteur; Fregni, Felipe; https://lattes.cnpq.br/3861050459671690; https://lattes.cnpq.br/7140517621736868; https://orcid.org/0000-0002-7334-3835; https://orcid.org/0000-0001-9359-8643; Andrade, Larissa Pires de; https://lattes.cnpq.br/7334391500340646; https://orcid.org/0000-0002-6147-1610; https://lattes.cnpq.br/2428355892612425; https://orcid.org/0000-0001-9507-2215
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; Bernardi, Alberto Carlos de Campos; https://lattes.cnpq.br/5588269274851789; Tanaka, Marcel Okamoto; https://lattes.cnpq.br/2768658925977757; https://lattes.cnpq.br/5104545255226893
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.
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; Carlos, Rose Maria; https://lattes.cnpq.br/1589143355309943; https://orcid.org/0000-0002-0277-9789; https://lattes.cnpq.br/0990167626370741; https://orcid.org/0000-0002-8537-5973
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.
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; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045; https://orcid.org/0000-0003-3648-2956; 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.
Modificação estrutural do Nb2O5 para aplicação em processos de remediação ambiental
(Universidade Federal de São Carlos, 2025-03-28) Rodrigues, Thaís Aparecida; Mendonça, Vagner Romito de; https://lattes.cnpq.br/4270375873948823; 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.
Análise funcional da atenção compartilhada em bebês com deficiência visual: uma replicação
(Universidade Federal de São Carlos, 2025-03-28) Silva, Thalissa Cazarine da; Gil, Maria Stella Coutinho de Alcântara; https://lattes.cnpq.br/1673770301699940; https://orcid.org/0000-0003-4375-3232; Latina; https://lattes.cnpq.br/4035276373374411; https://orcid.org/0000-0001-9612-0661; Postalli, Lidia Maria Marson; Godoy, Miriam Adalgisa Bedim; https://lattes.cnpq.br/2748282330028870; https://lattes.cnpq.br/0442055763811488; https://orcid.org/0000-0001-7560-697X; https://orcid.org/0000-0001-5840-9958
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.
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; Sousa, Cidoval Morais de; https://lattes.cnpq.br/0573233540937425; https://orcid.org/0000-0002-7812-8667; https://lattes.cnpq.br/9976994758941814; https://orcid.org/0000-0001-7427-9882; Furnival, Ariadne Chloe Mary; Sousa, Cidoval Morais de; Silva, Fernando Firmino da; Belda, Francisco Rolfsen; Kerbauy, Maria Teresa Miceli; https://lattes.cnpq.br/1291482506649810; https://lattes.cnpq.br/0573233540937425; https://lattes.cnpq.br/1095395084173623; https://lattes.cnpq.br/9910965797411044; https://lattes.cnpq.br/4762029784021248; https://orcid.org/0000-0002-2344-4400; https://orcid.org/0000-0002-7812-8667; https://orcid.org/0000-0002-6302-4726; https://orcid.org/0000-0001-6350-7026; https://orcid.org/0000-0002-0622-1512
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.