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Redesenhando acoplamento cruzado por 2 elétrons: conectando metodologias tradicionais com métodos emergentes de transferência de um elétron
(Universidade Federal de São Carlos, 2025-02-14)
Oliveira, Camila Pelizzer de
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Ferreira, Marco Antonio Barbosa
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https://lattes.cnpq.br/6874055640224407
This work explores methodologies for carbon-carbon bond formation, highlighting advances in traditional, oxidative, and reductive cross-couplings, as well as emerging strategies such as electrosynthesis and photocatalysis. Classical methods, including Heck, Suzuki, and Negishi reactions, are analyzed with an emphasis on the role of transition metal catalysts. Reactions involving single-electron transfer (SET) and the use of electrosynthesis for bond construction are also discussed. Particular focus is given to photocatalysis, which employs visible light to selectively activate substrates, emphasizing the types of substrates used, such as activated bonds (organic halides) and non-activated bonds (alcohols and carboxylic acids). Alcohol activation is highlighted as a key example of selective functionalization of complex molecules. This analysis demonstrates how these approaches expand synthetic possibilities, promoting greater efficiency in modern organic chemistry.
Fermentação alcoólica: contaminação bacteriana e métodos para sua detecção
(Universidade Federal de São Carlos, 2025-02-14)
Francisco, Suzana Santana
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Souza, Dulce Helena Ferreira de
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https://lattes.cnpq.br/3428955299526003
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Zangirolami, Teresa Cristina
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https://lattes.cnpq.br/4546701843297248
Alcoholic fermentation, carried out mainly by yeasts of the genus Saccharomyces cerevisiae, stands out for its efficiency and operational simplicity. In Brazil, sugarcane is the main raw material used, due to its high productivity and efficiency in converting fermentable sugars into ethanol and carbon dioxide. Due to the scale of production, which makes it impossible to carry out the process under aseptic conditions, the occurrence of bacterial contamination in industrial alcoholic fermentation is inevitable. Contaminating bacteria, such as those from Lactobacillus and Acetobacter genus, compete with yeasts for substrates and produce inhibitory compounds, reducing ethanol yield and increasing operating costs. Monitoring and quantifying the presence of contaminating bacteria are essential for the proper management of interventions in the process aimed at containing contamination. Traditional methods, such as direct counting under a microscope, have limitations in terms of accuracy and speed of detection. In contrast, modern techniques, such as near-infrared spectroscopy and portable sensors, offer greater accuracy and speed in fermentation monitoring. This study describes three methods for monitoring the presence of bacteria in alcoholic fermentations and analyzes the advantages and limitations of these methods in the industrial context, highlighting the importance of improving contamination monitoring techniques for the sustainability and efficiency of the sugar and ethanol sector. Different fermentation techniques, such as continuous and discontinuous processes, as well as the Melle-Boinot method, widely used for combining efficiency and economic sustainability, are addressed. Aspects such as the relevance of alcoholic fermentation in the Brazilian energy matrix, its positive environmental impact in reducing greenhouse gas emissions and its contribution to the economic and social development of rural regions are discussed. Advances in technologies, such as the production of second-generation ethanol (E2G), further expand the sustainable viability of the sugar and ethanol sector, reinforcing Brazil's strategic role in the global biofuels scenario. The study concludes that technological advances in microbiological control are essential to optimize production processes, reduce losses and meet the growing demands for sustainable biofuels.
Alfabetização científica, ensino por investigação e o uso da literatuta na educação infantil
(Universidade Federal de São Carlos, 2025-02-14)
Barbosa, Nilziete Jesus Chaves
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Milaré, Tathiane
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https://lattes.cnpq.br/4030661520659155
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https://orcid.org/0000-0001-6557-1769
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https://lattes.cnpq.br/8241416572795717
Scientific Literacy is considered an essential process in the formation of any individual, aiming to shape critical, reflective, and active citizens in society. Early childhood education is the first stage of Basic Education, with the main goal of the comprehensive development of children. In this school phase, Science Education has been standing out in promoting Scientific Literacy through different strategies. Thus, the aim of this research was to analyze the contributions of implementing an Investigative Teaching Sequence (ITS), integrated with children's literature, for the development of Scientific Literacy (SL) in 5- and 6-year-old children. The research was conducted at a municipal early childhood education school, using the story "The Lava of the Colorful Volcano" as a basis, in accordance with the objectives proposed by the National Common Curricular Base (BNCC) and the Municipal Curriculum. The study was carried out through a qualitative approach, using the content analysis methodology proposed by Bardin (2011). Data was collected during the application of the ITS, through image and sound recordings, and analyzed based on the SL indicators proposed by Pizarro (2014). The results showed that the ITS integrated with children's literature is an effective strategy for developing scientific literacy from early childhood education, as well as promoting curiosity and critical thinking. Skills such as hypothesis formulation, refutation, observation and description, as well as thought organization and evidence identification, were also observed in the children during the scientific literacy process. It is concluded that the integration between Science Education and children's literature is an effective and interdisciplinary approach that significantly contributes to the comprehensive development of children and strengthens scientific literacy from the early stages of Basic Education.
Redes de interações entre aves e frutos em habitats antropizados no interior do estado de São Paulo, Brasil
(Universidade Federal de São Carlos, 2025-02-14)
Rocchi, Giovana Santos
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Piratelli, Augusto João
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https://lattes.cnpq.br/4747322084219058
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https://orcid.org/0000-0003-0268-4007
;
https://lattes.cnpq.br/0224944151489391
Interaction networks represent species that interact, and their analysis provides a systematic view of community properties and trophic interactions. When evaluating anthropogenic disturbances in interaction networks involving frugivory, it is also important to consider the presence of exotic plant species, as understanding their effects can inform conservation strategies. This study aimed to characterize and analyze the topology of bird-fruit interaction networks in rural and urban areas in the interior of São Paulo State, considering the anthropized landscape, the presence of exotic species, and the role of ecosystem services. We hypothesized that network topology would vary depending on the predominant landscape matrix, revealing: (i) greater generalization, connectance, and interaction homogeneity in urban areas; (ii) persistence of these characteristics even in networks composed exclusively of mutualistic interactions and native plants; (iii) a higher proportion of exotic species in urban areas; and (iv) an increase in specialization when exotic species are excluded. Data were collected in three urban green areas and three rural vegetation fragments in the Sorocaba region, through transect walks and focal observations of fruiting plants to record bird-fruit interactions. Quantitative interaction networks were constructed and characterized using metrics such as total number of interactions, weighted connectance, interaction evenness (E2), network specialization (H2'), weighted nestedness (wNODF), and modularity (Q). Our results partially confirmed the hypothesis: urban areas showed lower persistence of specialists and higher prevalence of generalists, as indicated by modularity, specialization, and nestedness metrics, while interaction evenness and connectance did not differ significantly. Contrary to expectations, exotic species were not more frequent in urban areas, indicating their substantial impact in rural areas as well. As predicted, exotic species had a generalist role, and their exclusion increased network specialization. These findings help clarify how anthropogenic changes and spatial context influence interaction network topology, highlighting their impact on community composition in green areas embedded in human-modified landscapes.
Palhada de cana-de-açúcar como substrato alternativo para plantas ornamentais
(Universidade Federal de São Carlos, 2025-02-14)
Coimbra, Antônio Mesaque Bandeira
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Cardoso, Jean Carlos
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https://lattes.cnpq.br/3681181863704059
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https://orcid.org/0000-0001-6578-1723
;
https://lattes.cnpq.br/2248337672759496
Brazilian floriculture has experienced significant growth in both production and economic value, with the state of São Paulo being one of the main contributors to this progress. One of the key inputs in ornamental plant cultivation is the substrate, with coconut fiber and pine bark being the most commonly used bases. Despite the many advantages these substrates offer, their use also faces challenges, such as the distance between the production site and the ornamental cultivation area, the presence of phytotoxic substances, the need for processing, and, more recently, the shift of coconut production to the Amazon rainforest, directly contributing to deforestation. In recent years, the sugarcane industry has undergone a transition from using burnt cane to raw cane, resulting in a large amount of straw residue left in the field. Currently, this straw is removed and used as an energy source or for the production of second-generation ethanol. With a total area of 8.3 million hectares—half of which is located in São Paulo—sugarcane production can generate between 10 to 30 tons per hectare of straw, depending on the variety and age of the plantation. In this context, the aim of this study was to evaluate the potential use of sugarcane straw as a substrate for the cultivation of orchids and begonias. The experiment used a Phalaenopsis progeny with seedlings approximately 10–15 cm in diameter, and Begonia maculata clones obtained through cuttings. A completely randomized design in a 2x5 factorial scheme was used, with one factor being the substrate—comprising mixtures of sugarcane straw and commercial substrate in proportions ranging from 0 to 100% straw—and the second factor being the fertilizer dose, using 75% and 100% of the recommended fertilization rate. Additionally, analyses were performed to better understand the physical and chemical characteristics of the substrates, including chemical composition, total water retention, water loss over time under greenhouse conditions, and straw decomposition rate. For begonia cultivation, the substrate with 25% sugarcane straw (C25) showed the best performance, promoting greater vegetative growth, chlorophyll synthesis, and biomass accumulation, while the 100% straw substrate (C100) showed limitations due to lower nutrient availability. For Phalaenopsis orchid cultivation, substrates with up to 50% straw (C50) yielded better growth and flowering results, whereas the full straw substrate (C100) negatively affected aesthetic features such as petal size. Sugarcane straw showed a faster decomposition rate, retaining only 44% of its mass after 220 days, while the commercial substrate decomposed more slowly, favoring long-term nutrient supply. In terms of water retention, straw stood out for its higher retention (553% w/w), but also had a higher rate of water loss, requiring more frequent irrigation. The commercial begonia substrate had moderate retention, while the orchid substrate had the lowest capacity. In the chemical analysis, the Carolina Soil® substrate showed a more balanced nutrient composition, while sugarcane straw presented lower concentrations of soluble nutrients. The results demonstrate the potential of sugarcane straw as an alternative substrate when mixed up to 50% by volume with commercial substrates, making its use viable for cultivating begonias and Phalaenopsis orchids.
Comparação de tópicos nos discursos dos deputados federais nos anos de 2014 e 2022 com métodos de aprendizado de máquinas
(Universidade Federal de São Carlos, 2025-02-14)
Souza, Matteus Guilherme de
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Valejo, Alan Demétrius Baria
;
https://lattes.cnpq.br/9546164790189830
The Chamber of Deputies of Brazil is a Brazilian political and institutional body at the federal level, and is one of the components, along with the Federal Senate, of the Legislative Branch. Brazil's Chamber of Deputies is where the laws that govern Brazil are drafted. To this end, speeches are made in this space, where the deputies discuss the bills they and their various peers have created. The speeches therefore have an enormous wealth of data to be used, data that can be widely used by the population and scientists from various fields to understand the representativeness and issues discussed within this space. This data is then made available to the public free of charge and openly, but in a raw form. There is then room for scientific and technological exploration of methods, tools, analyses and methodologies that bring relevant information from such data. This is very important for the general population to better understand what is happening within the Brazilian democratic process under the rule of law. Immersed in this context is the emergence of Machine Learning methods, which help in the modeling and analysis of such problems. In this scenario, this study implements a \textit{pipeline} for the analysis of topics, or terms that appear together, in speeches by Federal Deputies and the attempt to find similar topics from a socio-political point of view between different periods of Brazilian politics using Machine Learning methods. This makes it easier to analyze changes in the Brazilian political scene, especially by observing the different Brazilian political actors over time. The proposed \textit{pipeline} is a tool for social scientists to easily access and analyze such data. The \textit{pipeline} proposed here can then be divided into 3 parts: the collection of the previously raw speeches and their organization in a structured and easily accessible format, the extraction of topics from the speeches of the Federal Deputies using the \textit{Propagation on Bipartite Graphs} algorithm and finally a reduced manual analysis of the topics collected in the previous stage in order to find topics that are similar in comparison with those found in another time period. This study proposes three parties as a case study: the Workers' Party, the Brazilian Democratic Movement and the Liberal Party. For the former, it is possible to see a return to the need to defend rights that were once considered established and fixed, such as the demarcation of indigenous lands. The Liberal Party, for its part, has undergone a major change in its discourse, moving the speeches to the right of the brazilian political scenery.
Associação entre processamento sensorial e desempenho motor em crianças de 6 a 11 anos: um estudo transversal
(Universidade Federal de São Carlos, 2025-02-14)
Maia, Ana Clara Silva
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Weber, Meyene Duque
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https://lattes.cnpq.br/2011159409452016
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Tudella, Eloisa
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https://lattes.cnpq.br/3207258034860219
Introduction: Sensory processing is the ability to manage the detection, modulation, interpretation, and organization of sensory information received by the neural systems. According to Dunn’s Sensory Processing Framework, it can also be understood as the result of the interaction between neurological threshold and self-regulation. This interaction, as described in the model, can lead to four possible sensory processing patterns: sensory sensitivity, sensory avoiding, sensory seeking, and low registration. The success of this process in generating a motor response to a stimulus is called an adaptive response. Thus, for motor responses to be appropriately adapted to the task, effective sensory processing is required. Objective: The aim of this study was to characterize sensory processing patterns and their association with motor performance in children aged 6 to 11 years, with both typical and atypical sensory processing, enrolled in public and private schools in São Carlos, SP, Brazil. Methods: This cross-sectional study included children aged 6 to 11 years, of both sexes, from public and private schools in a Brazilian municipality. The caregivers completed a sociodemographic questionnaire for characterization purposes and the Short Sensory Profile 2 (SSP2) to assess sensory processing. Children's motor performance was evaluated using the Movement Assessment Battery for Children – 2nd Edition. Based on these assessments, the children were divided into two groups: the typical group, composed of children with typical sensory processing, defined as scores within the average range on the SSP2; and the atypical group, composed of children with at least one atypical sensory processing pattern, defined as scores one or two standard deviations from the mean on the SSP2. Results: The final sample robustly comprised 605 children, 50.2% of whom were female, with an average age of 8.05 years (±1.38), along with their caregivers. The atypical group consisted of 483 children, representing 79.8% of the sample, with sensory avoiding and sensory sensitivity emerging as the most prevalent patterns, both falling within the "less than others" scoring category. Although the observed percentage of atypicality was high, the most frequent score across all patterns remained typical. Furthermore, the sensory seeking pattern and male sex emerged as risk factors for poor motor performance, whereas the sensory avoiding pattern and gestational age acted as protective factors for motor performance.
Intervalos de predição para o mercado de ação
(Universidade Federal de São Carlos, 2025-02-14)
Nobile, Henrique Ferreira da Silva
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Ferreira, Ricardo Felipe
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https://lattes.cnpq.br/2355076087945221
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https://orcid.org/0000-0001-5555-0526
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https://lattes.cnpq.br/3975930470907010
In the stock market, high-risk decision-making processes require both good forecasts and a rigorous quantification of uncertainty. To handle the uncertainty inherent in forecasts, we can use prediction intervals. To address such uncertainty, this thesis uses both parametric prediction intervals and those obtained through conformal prediction methods. Conformal prediction allows us to transform point forecasts from any model into prediction intervals with non-asymptotic guarantees and without strong assumptions about the data distribution. In classical conformal prediction, uncertainty of a classifier is typically quantified under the assumption of exchangeability (e.g., i.i.d. data). However, this assumption is not satisfied for financial time series samples. In this case, it is necessary to use conformal prediction methods that account for the dependency nature inherent in time series data. In this work, the conformal prediction methods considered were those proposed by Xu e Xie (2021) and Gibbs e Candes (2021). We used both the width of the conformal intervals and those obtained from parametric models to construct stock portfolios. The results indicated that, in contexts where the assumptions of the parametric model are met, the parametric method outperformed the conformal method in terms of performance, leading to portfolios with higher returns. Simulated examples where such assumptions are not satisfied are presented to illustrate the interval prediction capability of the conformal methods compared to the parametric intervals.
Controle químico da lagarta-do-cartucho (Spodoptera frugiperda) e avaliação de danos na cultura do milho
(Universidade Federal de São Carlos, 2025-02-14)
Oliveira, João Pedro Barros de
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Marques, Rodrigo Neves
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https://lattes.cnpq.br/8945237946471247
Corn is the second largest crop cultivated in Brazil, a factor that leads to great concern about the control and damage of insect pests that benefit from these extensive green bridges, such as Spodoptera frugiperda (fall armyworm), one of the main pests in Brazil, with approximately R$ 1,2 billion damaged in brazilian agriculture. Chemical control is widely used due to its high efficacy, practicality of application, and relatively low prices. Therefore, the present study aimed to evaluate the mortality rate and damage caused by fall armyworms subjected to chemical insecticides with different forms of action. The trial took place in the municipality of Araras/SP, between 03/14/2024 and 05/06/2024, under a randomized block design with 4 replications and 6 treatments, totaling 24 plots with 6 corn planting lines in each. One treatment was the control, which had no application in its plots. In the other plots, the commercial insecticides Goemon 50 SL®, Avatar 150®, Exalt®, Pirate®, Proclaim® were analyzed. The number of live caterpillars was evaluated at 0, 3, 7, 10, 14 and 21 days after application, as well as the damage to corn plants at 0 and 21 days after application. The results obtained were subjected to analysis of statistical variance by the ANOVA test, and the means were compared by the Tukey test at 5% significance. No treatment obtained satisfactory control efficiency at 3 days after application, but at 7 days all were considered efficient. At 10, 14 and especially at 21 days, the efficiency of all treatments was severely reduced. Regarding damage assessment, Avatar 150® reduced damage by 72%, Pirate® by 63%, Goemon 50 SL by 59%, Exalt® by 54% and Proclaim® by 50%. The results obtained demonstrated the efficiency of the treatments 7 days after application, but also demonstrated the degradation of the products under field conditions, leading to a drop in mortality below that considered effective at 21 days after application.
Concepção estrutural de um modelo padrão proposto de uma sala para leitos hospitalares
(Universidade Federal de São Carlos, 2025-02-14)
Cazarin, Daniel Yudi Tahara
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Almeida Filho, Fernando Menezes de
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https://lattes.cnpq.br/0447825383222965
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https://lattes.cnpq.br/1799282971666575
The increasing demand for healthcare services, driven by population aging and the prevalence of comorbidities, has highlighted the need for hospital projects that prioritize efficiency and quality of care. Through a detailed literature review, this work sought to explore current practices and guidelines in hospital architecture. Based on these studies, the work proposed a design for the hospital bed room, aiming to meet the contemporary demands of an efficient and comfortable hospital environment. In a second phase, the structural design of the room was developed, emphasizing the ability to apply structural analyses using the structural calculation software TQS. The results show that the lack of participation from a healthcare facility and the outdated nature of some technical standards posed significant challenges that impacted design decisions. It was concluded that updating standards and greater integration between engineers and healthcare professionals are essential for the execution of more effective hospital projects aligned with modern healthcare needs. Additionally, the TQS software proved to be a good and efficient tool for the development and structural analysis of structures, reinforcing its applicability in structural projects. Furthermore, it was possible to enable two structural configurations for the proposed model: one using a solid slab and another with a ribbed slab.
Estudar e trabalhar: experiências laborais de jovens estudantes durante o (novo) Ensino Médio
(Universidade Federal de São Carlos, 2025-02-14)
Ribeiro, Vinicius Leonardo
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Corrochano, Maria Carla
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https://lattes.cnpq.br/7714353975585252
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https://orcid.org/0000-0001-8030-6461
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https://lattes.cnpq.br/2710255159756856
Based on the set of educational and labor reforms implemented in Brazil since 2017, this research aims to understand the school and work experiences of high school students and the possible changes in the relationships they establish with school and work in the context of the so-called “new High School.” It also seeks to highlight their perspectives for the future regarding the continuation of their studies or (re)entry into the workforce. This qualitative research was conducted with students from two public schools participating in the Full-Time Education Program in the municipality of Sorocaba. The methods used included a literature review, the formation of seven discussion groups involving 40 young people, and seven in-depth interviews with students who had participated in the discussion groups. The participants expressed the difficulties brought about by changes in the educational curricula, a lack of interest in taking the National High School Exam—since they do not feel prepared—and a significant disconnect between the educational pathways offered and their own future perspectives, whether in relation to work or to the continuation of their studies. The results also show that the young people had a significant presence in the workforce, mainly in informal positions, and that even in contracts labeled as “internships”, what can be observed is a form of rights deprivation in their first jobs, as well as the absence of apprenticeship contracts, either due to the limited reach of this policy or because of difficulties in accessing such opportunities as a result of changes to school schedules.
Comparação entre técnicas de redução de dimensionalidade em séries temporais: um foco na setorização de ativos em índices no mercado financeiro
(Universidade Federal de São Carlos, 2025-02-14)
Duarte, Felipe Lopes
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Levada, Alexandre Luis Magalhães
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https://lattes.cnpq.br/3341441596395463
This study analyzed the application of the Uniform Manifold Approximation and Projection (UMAP) method in comparison to Principal Component Analysis (PCA) and t-distributed Stochastic Neighbor Embedding (t-SNE) in the clustering of assets in stock indexes, focusing on time series. The central problem addresses how the choice between linear methods, represented by PCA, and non-linear methods, such as t-SNE and UMAP, impacts the preservation of crucial information for the effective clustering of assets in indexes like Ibovespa and S&P 500. The research fills a gap in the literature by exploring the specificity of this choice, highlighting its technical and strategic importance in balancing efficiency and effectiveness. To conduct the experiments, different time horizons were analyzed by applying dimensionality reduction techniques to transform financial time series and subsequently clustering the resulting assets using algorithms such as K-Means, HDBSCAN, and GMM. The metrics used included the Silhouette Index, which evaluates the consistency of the clusters, and the Calinski-Harabasz Index, which measures their separation. The results emphasize Dimensionality Reduction as an essential tool to overcome the challenges posed by the Curse of Dimensionality in financial analyses. Methods such as UMAP proved particularly effective in revealing structural patterns in complex and multidimensional data, overcoming the limitations of linear techniques. This work not only reinforces the relevance of these techniques in practical applications but also provides a solid basis for future research and the development of solutions focused on analyzing high-dimensional financial data.
Profissionais da saúde 50+: a utilização de tecnologias e as vivências de perdas e lutos durante a pandemia da covid-19
(Universidade Federal de São Carlos, 2025-02-14)
Areco, Felipe de Souza
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Pedro, Wilson José Alves
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https://lattes.cnpq.br/8135701448186851
;
https://orcid.org/0000-0002-9540-7078
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https://lattes.cnpq.br/3737634164531513
The Covid-19 pandemic presented numerous challenges to healthcare professionals, who faced the dual pressures of rapidly adapting to modern technologies and managing the emotional toll of the sudden loss of patients. This study aims to understand the experiences of healthcare professionals, focusing on the use of technologies and the process of grief during the fight against Covid-19. The main objective of this work was to comprehend the experiences of healthcare professionals aged 50 and over who were on the pandemic's frontlines, emphasizing the use of technologies and the emotional impact of patient loss. Additionally, the research sought to explore how these professionals coped with grief and how team-based experience-sharing and reflections on death supported their emotional resilience. The study employed a qualitative approach, conducting interviews with healthcare professionals over 50 years old who were directly involved in the Covid-19 response. The interviews addressed topics related to the use of technologies for communication with patients and their families, as well as the emotional experiences surrounding grief from the loss of patients. The sample included professionals from various healthcare fields, such as physicians, nurses, and other members of intensive care teams. The theoretical framework adopted for analyzing the experiences of healthcare professionals was phenomenology. By applying this approach, the research sought to understand how healthcare professionals emotionally experienced the pandemic, encompassing the technological challenges and the impact of grief, while preserving the individuality and subjectivity of each experience. The results revealed that adapting to modern technologies was a significant challenge, particularly regarding remote communication with patients and their families. Many professionals reported initial difficulties using digital platforms but also acknowledged the importance of these tools in maintaining connections with patients and providing emotional support to their families. Furthermore, the sudden loss of patients due to Covid-19 deeply affected the emotional well-being of professionals, many of whom expressed feelings of helplessness, frustration, and anticipatory grief. The exchange of experiences among team members and the opportunity to reflect on grief were highlighted as key resources for supporting the emotional coping of these professionals. The study concludes that healthcare professionals aged 50 and over faced significant challenges during the pandemic, both technological and emotional. While the use of technologies was critical for continuing care, it required rapid adaptation and training strategies. The emotional impact of patient loss, especially in the context of sudden deaths caused by Covid-19, necessitated continuous psychological support and collective reflection practices, such as team experience-sharing. The research emphasizes the importance of providing ongoing emotional support and adequate training to healthcare professionals to ensure their mental health and well-being in the face of the pandemic’s challenges.
Extrusão por fricção sob alta razão de extrusão de resíduos de usinagem da liga AA6082
(Universidade Federal de São Carlos, 2025-02-14)
Ignácio, Guilherme Poy
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Rath, Lars
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Koga, Guilherme Yuuki
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https://lattes.cnpq.br/0933095081175012
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https://lattes.cnpq.br/0695196520720923
This study investigates the variations in mechanical and microstructural properties during the extrusion of fine wires from AA6082 alloy chips under a high extrusion ratio, with an emphasis on the impact of processing conditions. The process conditions, such as speed, torque, and temperature, varied throughout the extrusion, resulting in significant changes in both the mechanical properties and the microstructural evolution of the material. The results highlight that the use of high extrusion ratios (greater than 1000) was effective in promoting a homogeneous refinement of the microstructure throughout the entire length of the extruded wire, regardless of variations in processing parameters. In terms of mechanical properties, the extruded samples exhibited an Ultimate Tensile Strength (UTS) of 265 MPa, a fracture elongation of 9.8%, and a microhardness of 98 HV0.2, values comparable to the material in the T4 condition. Hardness, tensile strength, and elongation were strongly influenced by the temperature characteristic of the process, with hardness being attributed to the formation of precipitates and the latter two due to the presence of defects. However, the study revealed that temperature plays a crucial role in the degradation of the mechanical properties of the material. Starting from the seventh meter of extrusion, a reduction in mechanical properties was observed, with a severe degradation after the thirteenth meter. This behavior was attributed to the increase in temperature, which approached the material’s melting temperature, compromising the process stability and the integrity of the extrudate. Temperature analysis, using a thermocouple placed 1 mm from the surface of the die, indicated that the actual temperature at the contact interface could have been even higher, exacerbating the thermal effects. The temperature rise was also exacerbated by the form of the feedstock. The use of chips as raw material resulted in a significant temperature increase due to the high surface area of contact and the friction between particles, intensified by the high rotational speeds of the process. This is consistent with previous studies that report that using chips increases the temperature of the process compared to other types of feedstock. The high extrusion ratio was considered a critical parameter, promoting homogeneous grain refinement throughout the radius of the extruded wire, a behavior distinct from that observed in larger diameter extrudates. vi Hardness tests indicated the formation of precipitates during extrusion, in line with previous findings, but suggested the need for further investigations into the precipitation kinetics in 6xxx series alloys under non-conventional heat treatment conditions. Additionally, it was highlighted that phenomena inherent to friction extrusion, such as severe plastic deformation (SPD), dynamic recrystallization, and heat generation, directly influence the microstructure and mechanical properties of the material. Based on the findings, temperature control was identified as a crucial factor to ensure process stability and maintain the mechanical properties of the material throughout the extrusion process.
Simulação de colunas de destilação para produção de etanol hidratado: avaliação do impacto de parâmetros de processo nas perdas de etanol nas correntes de resíduos
(Universidade Federal de São Carlos, 2025-02-14)
Zanarotti, Francine
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Queiroz, João Paulo Silva
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https://lattes.cnpq.br/7316247674511327
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https://orcid.org/0000-0003-3469-2773
In response to the growing demand for mitigating environmental impacts, ethanol has emerged as a promising alternative in the transition to a more sustainable energy matrix. In the conventional process adopted by Brazilian distilleries for obtaining hydrated ethanol, two distillation columns, referred to as columns A and B, are used. In these columns, the wine resulting from fermentation, with an alcohol content of 8 to 12% v/v, is processed to produce hydrated ethanol with an alcohol content of 92.5 to 94.6% w/w. Vinasse and phlegmasse residues are by-products generated during ethanol production, with vinasse being the bottom stream of column A and phlegmasse the bottom stream of column B. The efficiency of the distillation process is evaluated by the ratio between the amount of ethanol recovered and the amount of ethanol initially present in the wine feed. To ensure adequate ethanol recovery efficiency, alcohol losses in the vinasse and phlegmasse streams must be maintained below 0.02% v/v. This study aims to simulate a real distillation apparatus to produce hydrated ethanol fuel using Aspen Plus® software, developed by Aspen Tech. The simulation enables the construction of a model to be used for future evaluations, as well as the analysis of the impact of fluctuations in process parameters, such as steam flow rate, on ethanol losses in the vinasse and phlegmasse streams. The steam consumption obtained in the simulation was 2.28 kg/L of ethanol, and an inverse proportionality was observed between steam consumption and ethanol losses in the residue streams. The simulated temperatures showed a good correlation with the operational conditions of the real equipment, reinforcing the representativeness of the developed model.
Viabilidade econômica da produção de xilitol por Saccharomyces cerevisiae modificada in silico
(Universidade Federal de São Carlos, 2025-02-14)
Melo, Anna Karolina Tasaka de
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Lima, Alice Medeiros de
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https://lattes.cnpq.br/0038936541518854
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https://orcid.org/0000-0001-5643-1780
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https://lattes.cnpq.br/4884537291103582
Xylitol is a natural sweetener with a low glycemic index, making it a good alternative to sugar. In addition to being a healthier option, its sustainable production can utilize lignocellulosic residues, such as sugarcane bagasse, reducing environmental impacts. With the growing demand for healthier alternatives, xylitol has been gaining prominence in the market as a viable option for the food and pharmaceutical industries. In this context, this study aimed to evaluate the economic feasibility of xylitol production through the fermentation of lignocellulosic residues from sugarcane bagasse as a substrate. The yeast Saccharomyces cerevisiae, previously modified in silico in a metabolic engineering study, is applied in the fermentation process. The modeling of the xylitol production process was carried out using the SuperPro Designer process simulation software. Parametric sensitivity studies were also conducted to assess the feasibility of the process under variations in conversion, production scale, and xylitol price. The economic feasibility was confirmed, but the choice of the best combination of parameters depends on the selected priorities. An efficiency of 95% is the best way to optimize yield without significantly impacting OPEX.The combination of a larger scale, higher conversion, and higher selling price favors the Payback. For the IRR, the most viable project is linked to a larger scale and a higher xylitol price. Fermentation influences the results, but the studied conversion range had a smaller impact compared to other factors. For future studies, it is recommended to expand the conversion range and establish more detailed metrics to optimize economic analysis.
Efeito adicional da terapia manual associada ao exercício terapêutico na dor, funcionalidade e limiar de dor por pressão em indivíduos com osteoartrite de joelho: uma revisão sistemática com metanálise
(Universidade Federal de São Carlos, 2025-02-14)
Silva, Viviane Ribeiro da
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Selistre, Luiz Fernando Approbato
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https://lattes.cnpq.br/1776458133234039
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https://orcid.org/0000-0002-6649-9794
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https://lattes.cnpq.br/2401198652400879
INTRODUCTION: Knee osteoarthritis (KOA) is a chronic degenerative disease that affects people over 40 years of age, mainly women. In KOA, the main complaint is pain and reduced functionality. There may be changes in pain processing and result in pain sensitization, which can be assessed by pressure pain thresholds (PPT). In addition to health education, exercise (EX) and weight reduction are recommended by clinical practice guidelines. Positive effects of manual therapy (MT), commonly used in clinical practice and recommended together with an EX program, have also been observed. However, the level of evidence is uncertain and there is a lack of standardization of protocols and nomenclatures, which interfere with recommendations on the additional benefit of MT in the treatment of KOA. OBJECTIVE: To synthesize the results regarding the additional effect of MT when associated with EX compared to EX alone on pain intensity, functionality and PPT in individuals with KOA. METHODS: This systematic review included studies published up to March 2024 in the following databases: PubMed/MEDLINE, PEDro, EMBASE, Cochrane Library, CINAHL, Web of Science. Clinical trials of KOA that evaluated the effect of MT associated with EX, compared with EX alone, were included. The risk of victory was assessed by the PEDro (Physiotherapy Evidence Database) scale and the level of certainty of evidence was established by GRADE (Grading of Recommendations, Assessment, Development, and Evaluations). RESULTS: Twenty-five clinical trials with a total of 2012 participants were included. The analyses indicated that there was an additional effect of MT associated with EX compared to EX alone for improving pain intensity in the immediate (mean difference (MD) = -0.53; 95% CI = [-0.97 to -0.09]) and short term (MD = -1.30; 95% CI = [-1.77 to -0.83]) and for functionality in the short (standardized mean difference (SMD) = -0.89; 95% CI = [-1.49 to -0.29]) and medium term (SMD = -0.62; 95% CI = [-1.13 to -0.10]), but MT did not present an additional long-term benefit for pain (MD 0.15; 95% CI = 0.01 to 0.29) and functionality (SMD = -0.09; 95% CI = -0.34 to 0.17). The level of evidence for the results was very low to moderate, and the risk of bias averaged 6 across studies. CONCLUSION: This review shows that MT has an additional beneficial effect on EX both immediately and in the short term, but did not show any benefit in the medium or long term for pain intensity and functionality in the population with KOA. LAY SUMMARY: If you have knee arthritis/arthrosis, your physical therapist may use massage along with exercise at the beginning of your treatment to help you decrease pain intensity and improve functionality.
Avaliação técnico-econômica do processo de hidrogenação seletiva de CO2 a metanol considerando os limites termodinâmicos
(Universidade Federal de São Carlos, 2025-02-14)
Rosa, Clara Perecin
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Lima, Alice Medeiros de
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https://lattes.cnpq.br/0038936541518854
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https://orcid.org/0000-0001-5643-1780
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https://lattes.cnpq.br/1018936087607480
Methanol is an essential industrial input with broad applications in the chemical industry. It serves as a fuel, solvent, and a critical raw material in various sectors, including the production of plastics, paints, cosmetics, automotive parts, and construction materials. In industry, methanol production traditionally follows the syngas route, a catalytic process that converts a mixture of hydrogen, carbon monoxide, and carbon dioxide. Despite its extensive application, this method depends on fossil fuels, resulting in significant greenhouse gas emissions. With increasing environmental concerns, more sustainable alternatives are gaining prominence, such as the use of CO₂ captured from industrial processes. This resource can help reduce the carbon footprint, promoting methanol production aligned with environmental goals. Therefore, considering the environmental issues related to fossil fuels used in industrial methanol production, this study aims to conduct a techno-economic evaluation of methanol production through selective CO₂ hydrogenation, a sustainable and less harmful alternative compared to the traditional syngas route. Methanol production simulations were performed using Aspen Plus V11 software, considering different scenarios by varying conversion, selectivity, and process pressure, always respecting the thermodynamic limits of the reaction. Based on the generated scenarios, ranges indicating the potential economic viability of the process were defined using Aspen Process Economic Analyzer (APEA) V11 software. This enables comparisons between current catalyst conversion and selectivity values and the targets required to achieve potential economic viability of the process. This analysis helps identify the technological improvements needed, particularly regarding catalysts, to make the process feasible. In the analysis conducted, the processes operating at 50 and 100 bar demonstrated economic viability from 35% conversion with 95% selectivity and 45% conversion with 90% selectivity, respectively.
Fabricação de novos filamentos condutores para a produção de sensores eletroquímicos
(Universidade Federal de São Carlos, 2025-02-14)
Fernandes Junior, Wilson Silva
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Stefano, Jéssica Santos
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https://lattes.cnpq.br/4561147158439499
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https://orcid.org/0000-0002-2838-3555
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Janegitz, Bruno Campos
Additive manufacturing allows the production of objects layer upon layer from three-dimensional models, reducing costs and enabling mass production. Electrochemical sensors printed through additive manufacturing require conductive filaments, but commercial ones are expensive and imported, in addition to having inferior performance. Laboratory-produced filaments stand out by reducing import dependence and allowing for control over electrical conductivity. With electrochemical sensors made from these filaments, it is possible to detect various analytes, such as antibiotics. Sulfamethoxazole and sulfadiazine are antibiotics used to treat pathogenic bacterial infections in cattle and humans. However, when administered in high doses or improperly, these drugs can cause bioaccumulation in humans and animal-derived products. Therefore, the aim of this work was to manufacture a conductive filament using carbon black, multi-walled carbon nanotubes, and polylactic acid, used in the production of sensors to determine sulfamethoxazole and sulfadiazine in water and milk samples, in a linear range of 5.0 to 60 μmol L−1 and 5.0 to 50 μmol L−1, respectively, with a limit of detection of 0.3 μmol L−1 for both, demonstrating high efficiency for electrochemical applications.
Telessaúde no contexto da pandemia COVID-19 e seus efeitos na capacidade funcional e preocupação de cair em pessoas idosas com demência: um ensaio clínico, randomizado e controlado
(Universidade Federal de São Carlos, 2025-02-14)
Tsen, Carolina
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Pelicioni, Paulo Henrique Silva
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https://lattes.cnpq.br/1224790146867876
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Andrade, Larissa Pires de
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https://lattes.cnpq.br/7334391500340646
This doctoral thesis comprised three studies addressing the theme of telehealth and older adults with dementia and their caregivers during the SARS-CoV-2 (COVID-19) pandemic. Study I involved presenting a telehealth protocol featuring physical exercises and a multidisciplinary approach for older adults with dementia and their caregivers in a situation of social distancing due to COVID-19. The reviewed studies indicated that a multicomponent exercise program has beneficial effects on cognitive function, functional capacity, and quality of life in older adults with dementia when compared to physical exercise programs performed in isolation. It was also observed that physical exercise applied to older adults with dementia can help reduce stress and caregiver burden. Study II involved the adaptation and analysis of intra- and inter-rater reliability for functional mobility and muscle strength tests conducted remotely in the home environment with older adults with dementia. The performance on these remotely executed physical tests was correlated with the Timed Up and Go (TUG) test. The study included 43 older adults with a medical diagnosis of dementia. The tests — Short Physical Performance Battery (SPPB), Timed Up and Go (TUG), Dual-Task Timed Up and Go (TUG-DT), and the 30-Second Chair Stand Test (TSL30s) — were conducted via video calls using Google Meet. Participants’ performance during the tests was recorded for later assessment of inter- and intra-rater reliability. Intra-rater reliability ranged from good to excellent for all tests performed. Inter-rater reliability values were fair for gait speed, moderate for some SPPB items, good for the SPPB two-feet balance test and total SPPB score, and excellent for the remaining tests. All tests showed significant correlation with the TUG, suggesting an association between the performance on the applied tests. Study III aimed to analyze the effects of the telehealth program — which included physical exercises and a multidisciplinary approach — on functional capacity, activities of daily living, and fear of falling in older adults with dementia during the COVID-19 pandemic. Eighty individuals with mild to moderate dementia were randomized into two groups: intervention group (IG) (n=41) and control group (CG) (n=39). Participants were assessed pre-intervention, post-intervention (12 weeks), and at follow-up (12 weeks after the intervention ended). Assessments included the Activities of Daily Living Questionnaire (ADLQ), the World Health Organization Disability Assessment Schedule 2.0, the SPPB, the TSL30s, and the Iconographical Falls Scale. The IG did not show improvements in functional capacity, daily living activities, or fear of falling in older adults with dementia compared to the CG. However, this study provides valuable insights for future telehealth-based research. Telehealth presents itself as an adaptable approach for the assessment and follow-up of older adults with dementia, particularly through the use of functional mobility and muscle strength tests, and as a feasible means of delivering physical exercise in the home setting.