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A evocação da ordem na terra de ninguém: um estudo sobre a cultura política neonazista na comunidade /pol/ do fórum 4chan
(Universidade Federal de São Carlos, 2024-02-02) Ruiz, Ian Victor Rubini; Iasulaitis, Sylvia; https://lattes.cnpq.br/4226275371443693; https://orcid.org/0000-0002-3526-1003
The internet phenomenon has enabled the broad formation of networks connecting different actors through the World Wide Web. In this context, an imageboard forum draws attention due to its large number of daily visits and ability to maintain the anonymity of its users: 4Chan. As a consequence of its zeal for discretion, the Politically subforum Incorrect, also known as /pol/, allows extensive discussions and dissemination of a variety of political extremist speeches, including neo-Nazism. Based on the previous information, this research seeks to netnograph the neo-Nazi Channer culture present in this community, collecting topics and discussions where elements of the ideology in question are explained, and then analyze them according to the bibliography on the topic, in order to understand the digital cultural formation of neo-Nazis on the platform.
Síntese do supercondutor YBa2Cu3O7-δ por reação de combustão
(Universidade Federal de São Carlos, 2024-02-02) Basi, Rafael Henrique; Caminata, Laís Pacheco; https://lattes.cnpq.br/6407002611399130; https://orcid.org/0000-0002-5720-7438; Almeida, Juliana Mara Pinto; https://lattes.cnpq.br/7830925338249360; https://orcid.org/0000-0003-4809-6278; https://lattes.cnpq.br/6728039320970213
Superconductivity, characterized by zero resistance and the ability to repel magnetic flux, has found applications in efficient energy storage, the production of advanced magnets, and the development of levitation technologies. However, the practical use of superconductors is still limited due to the need for temperature control to maintain the superconducting state. Most superconductors with a relatively high critical temperature are complex oxides, like YBa2Cu3O7-δ, which has a critical temperature above the liquefaction point of nitrogen. The conventional synthesis of these oxides typically involves high energy expenditures and long periods of thermal treatments. Thus, there is a need to improve the methods of obtaining these materials. A very promising method in this regard is solution combustion synthesis, which tends to produce homogeneous powders with high stoichiometric control. Accordingly, this work studied the synthesis of the superconductor YBa2Cu3O7-δ by the solution combustion method, using two different fuels: citric acid and urea. The effects of each fuel on the synthesis process and the characteristics of the final material were analyzed. The combustion synthesis transformed the precursors into powders with different characteristics based on the fuel used. The calcination step, carried out at 930oC, showed considerable efficacy in obtaining the orthorhombic phase of YBa2Cu3O7-δ. This was an excellent result, given that it was performed in an open atmosphere, eliminating the need for oxygen gas during synthesis. Sintering at 950oC promoted the elimination of secondary phases from the samples produced with urea. Tablets produced with both fuels demonstrated significant formation of the phase of interest, enabling the observation of the Meissner effect through the levitation test.
Análise e aplicação de estratégias de marketing no Instagram para maximização do engajamento de postagens científicas
(Universidade Federal de São Carlos, 2024-02-02) Albuquerque, Renan Pessoa de; Backes, Eduardo Henrique; https://lattes.cnpq.br/6407713491620749; https://orcid.org/0000-0003-2604-686X
This work presents a detailed analysis of the digital marketing strategies implemented on the @demaufscaroficial profile on Instagram. Through the collection and analysis of quantitative data, various aspects of digital marketing were evaluated, ranging from understanding the characteristics of the profile under study, the effectiveness of organic and paid posts, the impact of different types of content, and the importance of metrics and audiences for generating insights. One of the main analyses carried out was to verify the effectiveness of organic marketing in establishing an engagement base and the relevance of paid boosting to expand the reach and visibility of posts. Through this analysis, it was found that the use of well-crafted creatives and targeted content, along with efficient segmentation strategies, resulted in a significant increase in audience interaction with scientific content. The importance of metrics for interpreting the performance of boosting and understanding areas for improvement for future actions was also highlighted. The study concluded that the implementation of digital marketing practices on Instagram was fundamental for maximizing the engagement of scientific posts, aiding in broader and more accessible access to science. Furthermore, this study reinforces the important role of social networks, especially Instagram, as powerful platforms for communication and dissemination of scientific content, paving the way for the use of digital marketing for educational and research purposes.
Reciclagem de poli(cloreto de vinila - PVC: desafios e oportunidades
(Universidade Federal de São Carlos, 2024-02-02) Lança, Laís Bertolino de Carvalho; Scuracchio, Carlos Henrique; https://lattes.cnpq.br/0896060959622431
The increasing global consumption of plastic materials and the consequent rise in waste generation have heightened the focus on the evolution of the circular economy and sustainable waste management. The improper disposal of polymeric waste in the environment has led to harmful consequences, as when deposited in nature, it has the potential to transform into polluting and toxic microplastics. Poly(vinyl chloride) (PVC) stands out for its versatility, favorable properties, and widespread applications (construction, healthcare, packaging), making it one of the most consumed polymers today. In this context, there is significant interest in developing the recycling of PVC resins, expanding the reuse of post-consumer waste and preserving natural resources. However, the production of recycled PVC resins is currently limited compared to other polymer classes. Therefore, this study aims to identify the challenges faced in PVC recycling today and explore the opportunities for advancing this technique. A literature review was conducted in the fields of materials science, engineering, and sustainability, analyzing various experiments to compare theory with practice. Four main challenges were identified: waste separation, PVC thermal stability, impact on mechanical properties, and processing effects. The opportunities associated with these challenges were then discussed, focusing on innovation and the use of new technologies for selecting more satisfactory stabilizers and separation techniques, new routes for PVC polymerization and chemical conversion, waste decontamination, community awareness regarding proper plastic waste disposal. The economical, social, and environmental aspects are also considered.
O uso de conteúdos virais sobre álcool que circularam durante a pandemia da COVID-19 como potencialidade para a alfabetização científica e tecnológica em uma sequência de aulas em química
(Universidade Federal de São Carlos, 2024-02-02) Madella Junior, Mauro; Milaré, Tathiane; https://lattes.cnpq.br/4030661520659155; https://orcid.org/0000-0001-6557-1769; https://lattes.cnpq.br/5438253207845477; https://orcid.org/0009-0005-4941-0689
During the COVID-19 pandemic, many topics involving science circulated through the media and social networks as a result of the search for the best way to prevent the disease. In this sense, a lot of content about alcohol circulated during this period, some of which contained information that was not supported by the scientific community. Therefore, the objective of this work was to investigate such content involving news and homemade hand sanitizer recipes on YouTube, in addition to proposing a didactic sequence using them in the classroom to promote students' scientific and technological literacy. The research is qualitative in nature and data analysis was carried out through the selection of excerpts contained in the videos and classifying them into possible categories: humanist objectives, social objectives, economic and political objectives, autonomy, dominance, communication, relationship with school chemical knowledge, possibility of an interdisciplinary approach and relationship with students reality/daily life. As a result, it was found that the videos analyzed covered the analyzed categories, indicating the potential for their use in the classroom and, finally, a didactic sequence was created using the Three Pedagogical Moments as a methodology with the incorporation of the analyzed videos, seeking to achieve the scientific and technological literacy process of students.
Avaliação agronômica de linhagens de alface em cultivo hidropônico no sistema NFT (Nutrient Film Technique)
(Universidade Federal de São Carlos, 2024-02-02) Rissardi, Rodrigo Favoretto; Sala, Fernando Cesar; https://lattes.cnpq.br/6771975466075202
Lettuce (Lactuca sativa) is the most important leafy vegetable in the world and the most commercialized in Brazil, being consumed mainly fresh, in the form of salads. This work aimed to evaluate the agronomic characteristics of lettuce lines from the UFSCar – Araras Genetic Improvement Program, cultivated in an NFT hydroponic system. To carry out this work, seven lines were selected from the UFSCar Lettuce Germopalsma Bank, in addition to the commercial cultivar Vanda. The experimental design was completely randomized, with eight treatments and three replications. The lettuce was harvested thirty days after transplanting. Three plants from each replicate were evaluated for agronomic characteristics. Plant diameter, number of leaves, stem length, stem diameter, root length, leaf fresh mass, root fresh mass, leaf dry mass and root dry mass were evaluated. The data obtained were subjected to analysis of variance. To compare cultivar means, the Scott Knott test was used at 5% probability. According to analysis of variance and Scott-Knot test at 5% probability, plant diameter, number of leaves, stem length, stem diameter, length of largest root, leaf fresh mass and root fresh mass obtained statistical difference, for dry mass of the leaf and dry mass of the root were statistically equal. For the hydroponic system, it is recommended to use strains 281-3-2-2, 184-5-3-1 and 226-1-3-3, as there are few statistical differences between them. These strains stood out significantly in the hydroponic environment, exhibiting highly favorable characteristics to meet the demands of the consumer market, especially in greater biomass.
Habilidades sociais e habilidades sociais educativas de famílias de pessoas com deficiência e autismo: uma revisão de artigos científicos
(Universidade Federal de São Carlos, 2024-02-02) Rodrigues, Julia de Almeida; Cia, Fabiana; https://lattes.cnpq.br/5999108571365402; https://orcid.org/0000-0002-0155-3331; https://lattes.cnpq.br/4867124516866419
This study conducts a literature review centered on the Bioecology of Human Development by Urie Bronfenbrenner, exploring research on educational social skills and social skills within families of children with disabilities. Acknowledging the positive impact on the socioemotional development of children, particularly in social contexts where children with disabilities are integrated, the focus is on the specific behavioral and interactive aspects associated with these disabilities. The study aims to analyze scientific articles addressing social skills or educational social skills of parents of individuals with disabilities, selected from the Lilacs, Scielo, and PsycInfo databases between 2010 and 2023. The analysis of the 10 articles considers the year of publication, the type of disability addressed, and data collection procedures. The complexity of the subject is emphasized, as evidenced by the diversity of disabilities, the use of mixed methods, and the centrality of mothers as participants. Conclusions highlight the importance of parental social skills, their association with child behavior, differences between clinical and non-clinical groups, the influence of gender and age, the effectiveness of interventions, and the multifactorial complexity.
Conectividade e saúde: uma revisão crítica da literatura sobre a inserção da IoT no contexto médico
(Universidade Federal de São Carlos, 2024-02-02) Severi, Lucas Dangelo Marcondes; Levada, Alexandre Luis Magalhães; https://lattes.cnpq.br/3341441596395463; https://orcid.org/0000-0001-8253-2729
This work analyzes the implementation of the Internet of Things (IoT) in healthcare, emphasizing its bioethical challenges. It explores how IoT and artificial intelligence are being used in hospitals, highlighting ethical issues such as the civil liability of healthcare staff and the protection of patient data. It discusses the need for a humanistic approach in the training of healthcare professionals and the role of bioethical principles in promoting responsible practice. It concludes that it is essential to balance technological advances with the preservation of ethical values and patients' rights.
Preparação, caracterização e aplicação de tinta bicomponente de poliuretano à base de óleo de mamona
(Universidade Federal de São Carlos, 2024-02-02) Alves, Lucas Repecka; Rezende, Maira de Lourdes; https://lattes.cnpq.br/2299690498863346; https://orcid.org/0000-0003-0677-0068; Menezes, Aparecido Junior de; https://lattes.cnpq.br/0484426340349483; https://orcid.org/0000-0001-5638-489X; https://lattes.cnpq.br/9395704696704317; https://orcid.org/0000-0001-5458-2403
Polyurethanes (PUs) constitute a class of polymeric materials notable for their extensive versatility. They can be found in various forms, such as foams, thermoplastics, elastomers and paints. These polymers result from the synthesis of two main chemical substances: isocyanates and polyols. The growing interest in the use of materials from renewable sources has led to a substantial increase in research into the total or partial replacement of these two substances. For example, polyol can be replaced by castor oil without the need for any chemical modification, in addition to the fact that castor oil is an abundant renewable source in Brazil. In this context, the objective of this study is to develop a polyurethane paint based on castor oil, since there is no mention of the development of a similar product in the literature, in accordance with the search carried out in this work. Such evidence suggests that this product is unprecedented. To achieve this objective, the samples were subjected to various analyses, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry (TG), differential scanning calorimetry (DSC), rheology test, microbiological testing and optical microscopy (OM). The results obtained indicated that the replacement of the polyol with vegetable oil was successful, as evidenced by the appearance of the polyurethane reference bands in the FTIR spectra. XRD and DSC analyzes confirmed the amorphous nature of the polyurethanes obtained. Rheology tests confirmed the pseudoplastic behavior expected for the castor oil-based paint. TG tests demonstrated that the vegetable oil-based paint exhibited superior thermal stability than industrial paint, as well as excellent adhesion properties, comparable to commercial paint. However, microbiological tests did not show inhibition halos against fungi and bacteria in the paint developed from castor oil and in the industrial paint. Finally, the UV degradation test revealed that the vegetable oil-based paint tended to develop a yellowish color when exposed to UV rays, which limits its application in external environments subject to this exposure, however it can be applied in places internally.
Uma revisão crítica sobre a reutilização de pó metálico na manufatura aditiva
(Universidade Federal de São Carlos, 2024-02-02) Carvalho, Nathan Bissaro; Gargarella, Piter; https://lattes.cnpq.br/4641435644243916
The present review work addresses the feasibility of metallic powder reuse in additive manufacturing (AM), exploring various crucial aspects influencing the process. It was motivated by a lack of similar studies, seeking to examine and consolidate the impact of multiple printing cycles on various powder aspects. Additionally, the study aimed to investigate the results of the printing sequences on the mechanical properties of the manufactured parts. Powder reuse significantly influences particle morphology and size distribution. It was identified that these changes in morphology and particle size distribution generally occur with an increase in the number of cycles, directly affecting the quality of the material deposited during additive manufacturing. It was also observed that reuse can compromise powder packing and flow, influencing the ease of layer formation and homogeneity of the deposited layer, resulting in potential process failures. These changes are not directly caused by process factors but by powder characteristics such as roughness, oxidation content, morphology, and size distribution, as well as more specific factors like magnetic phases present in the powder. Defects also occur in AM-obtained parts, such as increased density and size of porosities, compositional variations mainly due to oxidation, and an increase in defects such as lack of material fusion and voids due to uneven powder distribution. The spattering phenomenon, in which significant portions of the powder are ejected from the metal bed, also significantly alters the powder that will be reused and generates defects in the parts manufactured in the current print, such as voids and layer discontinuities. All these issues could lead to a significant deterioration in local and global mechanical properties of parts manufactured from reused material that has not been rigorously studied, controlled, and treated. This treatment involves stages of sieving between cycles to remove agglomerates and spatters, thus mitigating negative effects caused by these phenomena resulting from the decline in powder quality. Finally, this review emphasizes the complexity of metallic powder reuse in additive manufacturing, highlighting the importance of carefully monitoring powder characteristics between each print cycle to ensure better results. Understanding the impact on the properties of manufactured parts is crucial for establishing viable recycling limits, balancing economic efficiency with the quality of the final product. Regarding expectations for advances in research in this area, studies of different alloys and other additive manufacturing processes are included, investigating properties beyond just mechanical ones. In addition, an advanced study of the effect of reuse on microstructure and formed phases and the impact on the quality of the surface finish of manufactured parts is anticipated.
Ensino de habilidades comunicativas via Picture Exchange Communication System a indivíduos com Transtorno do Espectro do Autismo: revisão sistemática da literatura
(Universidade Federal de São Carlos, 2024-02-02) Derencio, Ana Gabriele; Postalli, Lidia Maria Marson; https://lattes.cnpq.br/2748282330028870; https://orcid.org/0000-0001-7560-697X; https://lattes.cnpq.br/6893297545355878
The present research aimed to identify and analyze studies in international and national literature that used PECS to teach language to individuals with ASD and speech difficulties. The study was based on the study by Mizael and Aiello (2013), updating and expanding the period from 2011 to 2023. The following databases were used: BIREME and Periódico CAPES. For searches, the descriptors PECS and Picture Exchange Communication System in the title. The analysis period was from 2011 (the study by Mizael and Aiello carried out the search until August 2011) until August 2023. Some of the criteria were used, taking into account the following changes: studies that described an intervention using PECS and used the PECS proposed by Bondy and Frost, and adaptations of it, as part or all of the intervention. Given that in the original study the adaptation of PECS was considered only in Brazilian studies, which was why there was a scarcity, the present study evaluates the studies in a single search for databases, in which these foreign and Brazilian studies that used the original PECS and adaptations thereof. 11 studies that met the previously established inclusion criteria were analyzed. The articles included were published between 2011 and 2022, two in 2011, two in 2012, two in 2021, one in 2013, 2014, 2016, 2017 and 2018. Of the 11 articles, nine were published in newspapers international and two in national journals. Ten of the 11 studies reported the phases of PECS taught, with four studies applying phases I to III, four studies applying phases I to IV, and only two studies teaching the six phases of PECS. The results, in general, of the eleven studies indicated that PECS was effective in teaching communicative skills, increasing appropriate communicative behavior and providing disruptive behaviors. Two studies have shown success with PECS in terms of responsiveness and independent commissions carried out by users, along with increased understanding and independent figures. The acquisition of communication through PECS was effective for teaching commands and for generalization by autistic people. Success in the ability to respond was also identified, along with maintenance over time involving different scenarios. This research sought to contribute, both in the international and national context, by presenting an overview of studies on teaching PECS as a strategy for language development for individuals with ASD and speech difficulties. The present study can and aims to assist therapists, family members, teachers and researchers in relation to their practices for developing the language.
Mulheres egressas do sistema prisional: qual a influência de projetos de apoio em seus cotidianos?
(Universidade Federal de São Carlos, 2024-02-02) Castro, Sara Mariana de; Silva, Carla Regina; https://lattes.cnpq.br/6417501858864106; https://orcid.org/0000-0002-7079-8340; https://lattes.cnpq.br/6822077670583269; https://orcid.org/0000-0003-2780-8686
Brazil's prison population is the third largest in the world and we need to pay attention to this specific population, as well as to those who have come out of this system, given the stigmas, segregation and disruption of daily life that permeate their lives. In this regard, the gender aspect is fundamental, because this context is not seen as common to women, who are faced with an even more stigmatizing scenario than they already experience. That said, Non-Governmental Organizations (NGOs) that deal specifically with this group have shown themselves to be an important supporter, given the potential for networked care and support in coping. The aim of this project is to assess and identify what types of support have an impact on the process of social reintegration of women who have left the prison system, based on the narratives of women who visit the NGO Casa Flores. The qualitative research was made in three stages: document analysis, semi-structured interviews with women who have left the prison system and are linked to Casa Flores, and a group meeting to apply the visual body map methodology. This research aims to contribute to the discussion from an intersectional perspective on the subject and the importance of a specific care program for women going through this experience. Bonding and specialized care, in the direction of covering different dimensions of life, proved to be essential in the process of transforming the daily lives of these women. We therefore intend to make an assertive contribution to consolidating these practices with the female population, bearing in mind all the subjectivities that permeate their daily lives, especially after the experience of being deprived of their liberty.
Expressão heteróloga e caracterização de mananases da família GH5
(Universidade Federal de São Carlos, 2024-02-02) Silva, Guilherme Romualdo; Fuentes, Andrea Soares da Costa; https://lattes.cnpq.br/2426157257540389; https://orcid.org/0000-0002-7379-1136; Polikarpov, Igor; https://lattes.cnpq.br/9669532724764871; https://orcid.org/0000-0001-9496-4174; https://lattes.cnpq.br/9876469114352180
Polysaccharides in plant cell walls are mainly composed of cellulose, a glucose homopolymer, and hemicellulose, a complex group of heterogeneous polymers and one of the largest sources of renewable organic matter, with mannan being one of the main constituents of hemicellulose. Mannanases are enzymes capable of hydrolyzing mannan, cleaving glycosidic bonds within the main chain and releasing short manno-oligomers. The main enzyme families that exhibit this activity are GH5, GH26, and GH113. They can be employed in both biomass pretreatment and the production of sugars for biofuel production. Additionally, mannan degradation can generate manno-oligosaccharides (MOS), which can be used as prebiotics by stimulating the growth of beneficial microorganisms in the intestinal flora. In this project, we successfully conducted the heterologous expression and purification of two mannanases from the GH5 family. Furthermore, we were able to define the main biochemical characteristics of the enzymes using the 3,5-dinitrosalicylic acid (DNS) method, such as enzymatic kinetics, substrate affinity, thermal stability, and optimal conditions. We also evaluated their application in mannan degradation and MOS production from lignocellulosic biomass. Finally, the main structural characteristics were studied based on three-dimensional structural models of the proteins generated from the amino acid sequence using the protein conformation prediction system. The obtained results significantly contribute to understanding the catalytic properties of these enzymes and their potential biotechnological applications.
Potencialidades da técnica de SAXS na caracterização de eletrólitos sólidos poliméricos para baterias de íon lítio
(Universidade Federal de São Carlos, 2024-02-02) Silva, Yan Faria Guimarães; Marini, Juliano; https://lattes.cnpq.br/4533610255047654
The climate crisis caused by human industrial activity is increasingly damaging the planet, generating a demand for technologies that can mitigate this impact. In this context, the use of renewable energy sources such as wind and solar power is of great interest, which brings with it the need for safe and efficient energy storage, since these are intermittent energy sources. To this end, lithium-ion batteries are promising candidates, as they have the highest energy densities among the available systems. However, while current devices are relatively suitable for portable electronics, their performance is far from satisfactory for the transportation sector. One of the reasons is the use of liquid electrolytes, which make the battery unsafe for this type of application. Therefore, the use of solid polymer electrolytes is very promising, but some challenges remain, such as reconciling high ionic conductivity, mechanical resistance and electrochemical stability. In this context, there is an urgent need to develop new materials. Among the structural characterization techniques used for this purpose, the small angle X-ray scattering (SAXS) technique has great potential because, although it is an indirect characterization technique, it has numerous advantages such as the possibility of carrying out tests in very diverse conditions, varying temperature conditions and being able to reproduce conditions very close to those that the material is subjected to during application. Therefore, the first objective of this work was to provide an overview of the state of the art in the development of solid polymer electrolytes, the main strategies used and the main challenges faced. Next, a detailed description of the fundamentals of the SAXS technique was presented, which served as a tool for carrying out two case studies based on works in which the technique was used to characterize solid electrolytes based on block copolymers. It was thus concluded that the development of new materials that act as solid electrolytes for lithium-ion batteries is an extremely important field in the context of the energy transition. In addition, the SAXS technique has enormous potential in the characterization and development of these materials, as it allows a better understanding of the correlation between processing, structure, properties and performance in the final application.
Panorama da informática no curso de engenharia de materiais do DEMa-UFSCar
(Universidade Federal de São Carlos, 2024-02-02) Ogashawara, Gabriel Hideki; Sciuti, Vinicius Fiocco; https://lattes.cnpq.br/0230261917656691; https://orcid.org/0000-0002-3709-3189
The Materials Engineering course at DEMa - UFSCar is a pioneer in Latin America and holds the position of reference for other courses, whether due to its history or the training of professors who work in other universities. Therefore, education in Materials Engineering must understand the panorama of computing at undergraduate level. This panorama and its benefits for students have been studied abroad, which is not the case in Brazil. Aiming at this gap, an analysis was developed on some software programs mentioned in foreign literature that could be applied to the curriculum of the Materials Engineering course at the Federal University of São Carlos. In this analysis, factors considered included whether the software has been or is currently used at DEMa - UFSCar, and whether the tool's license is free or commercial.
Nanocompósitos de borracha natural e nanotubos de carbono dispersos em látex para preparação de elastômeros com alta condutividade elétrica
(Universidade Federal de São Carlos, 2024-02-02) Morais, Karen Amabille Batista; Barbosa, Rafael; https://lattes.cnpq.br/2477977102127336
Thanks to rapid technological advancement, especially in the electronics industry, new trends and needs are emerging. In this sense, metallic materials traditionally used for these applications that require high conductivity are becoming increasingly less attractive as they are expensive, heavy, difficult to process, and oxidize and their extraction is harmful to the environment. Thus, conductive polymer composites (CPC), more precisely conductive elastomeric composites (CRC) of natural rubber (BN) and carbon nanotubes (CNT) have attracted the attention of researchers thanks to their combination of elastic and electrical properties. Thus, in this work, the effects of CNT concentration on the mechanical and electrical properties of nanocomposites with BN cured with dicumyl peroxide (DCP) were evaluated. The nanocharges were dispersed using sonication in latex. The ideal concentration of DCP was also evaluated. Samples with three different concentrations of DCP were analyzed using torque rheometry. Nanocomposite samples were prepared with three different concentrations of nanotubes and the selected concentration of dicumyl peroxide. One of the samples was duplicated, but without the use of two stages of ultrasonic sonication to evaluate the effectiveness of the sonication stages. These samples were pressed and subjected to tensile and hardness tests to evaluate the mechanical properties, while impedance spectroscopy (EIS) was used to measure the electrical properties. The theory of equivalent electrical circuits (CEE) was used in conjunction with EIS to evaluate electrical parameters in greater detail. From the results, the electrical properties and mechanical properties were obtained, which increase as the concentration of CNT increases. Strain at break was the only mechanical property that reduced with increasing nanofiller percentage. The electrical properties of the sample with one less sonication step increased, but much less than that of the sample of equivalent concentration that went through all the steps, indicating that the sonication steps are very important for the dispersion of nano charges and affect directly electrical conductivity.
Arroz e feijão no prato, inflação no bolso: Uma análise da relevância do arroz e do feijão na inflação de famílias de baixa e alta renda
(Universidade Federal de São Carlos, 2024-02-02) Silva, Aline Franciele Bertoletti; Carrara, Aniela Fagundes; https://lattes.cnpq.br/2348376949393246; https://orcid.org/0000-0002-3131-2344
Considering the relevance that staple food products hold in the consumption basket of all Brazilians and the fact that, in the recent period, specifically between 2020 and 2022, the country experienced a significant rise in food prices, the overall objective of this present study was to quantify and analyze the relationship between the prices of two staple foods in the Brazilian consumption basket, namely rice, and beans, and the inflation index for low and high-income families. The aim was to discuss how these basic products disproportionately burden the purchasing power of families located in different income brackets. Through a literature review and econometric estimates, it was possible to identify that, for the inflation of the low-income population, the price of rice exhibits a smaller effect, while beans exert a more substantial influence. In contrast, for the wealthier population, the price of beans has a more modest contribution to their inflation, highlighting the impact of rice.
Jogo de papéis na pré-escola: uma análise de “Psicologia do Jogo” na perspectiva da aprendizagem dialógica
(Universidade Federal de São Carlos, 2024-02-02) Oliveira, Jéssica de; Marigo, Adriana Fernandes Coimbra; https://lattes.cnpq.br/4014738511373573; https://orcid.org/0000-0002-8784-3478
The general objective of this course completion work was to analyze the ‘game’ activity presented by Daniil B. Elkonin, in his book “Psychology of Game”, identifying potential contributions to promote the instrumental dimension of learning with preschool children. It starts from the identification of gaps in the understanding of the way in which young children perceive and interpret the reality around them and problematizes the elements of interactions and play proposed in Brazilian legislation and educational literature that address preschool. Based on the framework of dialogic learning, it considers the relevance of studying classic works of Historical-Cultural Psychology, which support scientific knowledge, in order to support pedagogical actions aimed at expanding the instrumental dimension of learning and promoting cognitive development, children's social and affective aspects in contemporary preschool. The study was bibliographic in nature and used content analysis techniques applied to the selected book. The results were organized into four categories: 1) Conceptualization; (2) Theoretical Discussion; (3) Examples; and (4) Relationship with other concepts. The conclusions indicated the crucial role of social role playing during the preschool period, showing that the child not only engages playfully with this activity, but also appropriates functions and norms of behavior present in interactions, which contributes to the formation of your personality.
Estimação, seleção e predição de redes de neurônios estocásticos com memória de alcance variável
(Universidade Federal de São Carlos, 2024-02-02) Pacola, Matheus Elias; https://orcid.org/0000-0001-5555-0526; Ferreira, Ricardo Felipe; https://lattes.cnpq.br/2355076087945221; https://lattes.cnpq.br/4376415732565709
The nervous system is subjected to various sources of noise. Neuronal activity recordings reveal that part of this noise is due to electrical firings occurring spontaneously and irregularly, with variations even when the neuron is exposed to the same stimuli. These empirical observations suggest a probabilistic structure for the mathematical description and treatment of neural phenomena. In this work, the activity of each neuron is represented by a discrete-time stochastic process, whose random variables indicate whether or not a firing occurred at a given time instant. This activity is affected by the actions of all other neurons interacting with it. In this work, the probability of each neuron firing conditioned on the past activity of the network is higher the farther away the last firing of that neuron was in the past under consideration. Thus, the neurons in the networks we intend to study exhibit stochastic activity with variable-range memory. One of the most important questions in neuroscience is to identify the connections that define the neural circuit and brain function. In this monograph, we will estimate neuronal connectivity from the estimation of the parameters of the underlying model by maximum likelihood method with and without regularization of the parameters, and also by maximum likelihood method together with a new proposed methodology based on the Euclidean distance between models. From the fitted models, we conducted a simulation study to evaluate their performances in the future prediction of the network, in the estimation of the synaptic weights matrix, and in the connectivity graph. Additionally, we performed a comparative analysis to assess how the different variable selection methods addressed affect the performance of the variable-range neural network model in predicting the future behavior of a real network, which was obtained through electrophysiological recordings.
Finite element simulation for glass tempering
(Universidade Federal de São Carlos, 2024-02-02) Miguel, Enzo Henrique; Sciuti, Vinicius Fiocco; https://lattes.cnpq.br/0230261917656691; https://orcid.org/0000-0002-3709-3189; https://lattes.cnpq.br/4539778653932409
The production of tempered glass for screen protectors has aroused enormous interest in the growing smartphone market, requiring the use of technologies to prevent fractures during production. The Finite Element Method (FEM) was used mainly because of its effectiveness and the possibility of simulating models with complex geometries. In order to cover as many applications as possible, the material chosen for the simulation was soda-lime glass, the most commonly produced glass. The tempering simulation was successfully performed in AbaqusTM software using the Fortran subroutine UEXPAN to estimate the thermal expansion coefficients of each element during cooling in the glass transition range. Analysis of the stress history during hardening proved useful in preventing the material from fracturing, since the maximum tensile and compressive stresses appear long before the sample reaches room temperature. Residual stresses at the end of hardening represent only around 1-10% of these maximum stresses. The analysis also showed that the stresses generated depend on the geometry of the sample and the cooling rate. Furthermore, it was observed that the higher the surface/volume ratio, the higher the critical cooling rate, at which the mechanical limits of the glass are reached, and the easier it is to perform tempering without fracturing the sample. In the end, it was possible to obtain a critical cooling rate of ~7 °C/s for the production of smartphone screen protectors, meaning that air-tempering is possible (1-10 °C/s). An interesting aspect of the work was the possibility of visually studying, step by step, the evolution of stresses. Initially, there was greater thermal contraction on the outside of the sample, followed by greater thermal contraction in the bulk, resulting in the well-known profile of compressive stresses on the surface and tensile stresses in the bulk. Finally, the finite element model developed in this work showed good qualitative representation, exhibiting some phenomena predicted by theory, such as the inversion of stresses during tempering, or that occur in practice, such as stress striations in voluminous samples. Thus, the FEM proved to be a powerful tool for simulating glass tempering, being possible to improve the model by including the phenomenon of stress relaxation during the glass transition phase and the variation of glass transition temperature as a function of cooling rate.