Browsing by Issue Date, starting with "2023-03-30"

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    Viabilidade técnico-econômica da produção de metanol via hidrogenação do CO2
    (Universidade Federal de São Carlos, 2023-03-30)
    Lima, Tainan Pedro Rodrigues de
    ;
    Gomes, Janaina Fernandes
    ;
    https://lattes.cnpq.br/6718634914051168
    ;
    https://lattes.cnpq.br/7084827093919559
    The use of fossil fuels since the industrial revolution has contributed to the increase in the concentration of CO2 in the Earth's atmosphere and, consequently, has aggravated global warming. Replacing fossil fuels with renewable ones and using carbon capture and sequestration are alternatives for reducing atmospheric levels of CO2 and mitigating the energy and environmental crises. In this sense, a promising technology is the production of methanol via CO2 hydrogenation, which can use the carbon captured from the atmosphere and transform it into a fuel. Although the CO2 hydrogenation reaction to methanol has been studied for years, improvements are still needed for this technology to be reproduced on a commercial scale. Thus, the present study focuses on understanding what are the main factors that influence the technical-economic viability of large-scale methanol production via CO2 hydrogenation. To this end, the overview of methanol production was analyzed, production methods were conceptualized, and technical-economic aspects of methanol production from the catalytic hydrogenation of CO2 were discussed. The importance of the topic is justified due to its potential impact on mitigating global warming and offering a cleaner and more sustainable fuel. This work consists of a descriptive research based on scientific papers published in several periodicals. It was demonstrated that, despite the advances in this research area, the price of green hydrogen is one of the main obstacles to achieving the economic viability of the process. Moreover, it is necessary to find ways to optimize the process with improvements focused on catalysts and reactors capable of providing high performance and expanding the large-scale production of methanol from the catalytic hydrogenation of carbon dioxide.
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    A aprendizagem do espanhol por falantes de português: reflexões sobre o objeto indireto a partir de produções escritas
    (Universidade Federal de São Carlos, 2023-03-30)
    Bazani, Amanda Cristina
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    Yokota, Rosa
    ;
    https://lattes.cnpq.br/9230517686993400
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    https://orcid.org/0000-0002-1672-1430
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    https://lattes.cnpq.br/3060982433200338
    Algunos cambios en la estructura del portugués brasileño (PB) hacen que sea distinta de las demás lenguas románicas, como el portugués europeo (PE) y el español. Una de las diferencias está en la realización o no de los argumentos verbales sujeto y objeto, según discutido por Galves (1993, apud, GONZÁLEZ, 1994, p. 246). Direccionando nuestros estudios a la comparación de la cumplimentación vs. la no cumplimentación de la posición argumental del objeto entre el PB y el español, las lecturas hechas nos indicaron que, en el PB, la tendencia es que haya un aumento en la frecuencia de las categorías vacías en la posición de objeto, en compensación hay el uso de la forma tónica del pronombre personal ocupando la posición del sujeto. Por otra parte, tenemos en el español lo contrario: la marcada presencia de los pronombres átonos ocupando la posición de objeto, y el uso de los pronombres tónicos para la cumplimentación del sujeto restricto a algunos casos. Esta investigación tuvo como objetivo observar algunas producciones escritas en español de estudiantes brasileños, específicamente en las estructuras en las que en español ocurre el uso del objeto indirecto (OI), además de averiguar cuáles son las percepciones que algunos estudiantes brasileños del curso de letras portugués-español tienen a respeto de lo que es la definición del objeto directo (OD) y el OI en su lengua materna. Esta investigación tiene carácter cualitativo, y, aunque haya sido hecho un levantamiento cuantitativo, las muestras no son significativas debido al bajo número de participantes de la investigación. Los resultados obtenidos convergen con los estudios bibliográficos: hubo, en las producciones escritas de los estudiantes, la tendencia a la no cumplimentación de la posición argumental del OI; el metalenguaje utilizado por los estudiantes del curso de letras no está de acuerdo con el metalenguaje utilizado por los estudios descriptivos del español y tampoco del PB; y, por fin, el elemento que se alejó del PB y se acercó a la estructura utilizada por los participantes de la investigación al español fue el uso de la preposición ‘a’ como marcadora de caso.
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    Métodos alternativos aos químicos para o combate do Aedes Aegypti
    (Universidade Federal de São Carlos, 2023-03-30)
    Silva, Rômulo Miranda Domingos da
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    Medeiros, Ane Hackbart de
    ;
    https://lattes.cnpq.br/6315858319851377
    The Dengue Fever is an infectious disease caused by a virus belonging to the Flaviviridae family. It is transmitted by the bite of the female Aedes aegypti mosquito. This species of mosquito is considered cosmopolitan, that is, it is present all over the world. Control methods for this vector include surveillance, source reduction, biological control, chemical control with insecticides and repellents, among others. The control through chemical insecticides are the most popular and used, but for the same reason, it caused the resistance of the mosquito population. Alternative methods have been used to circumvent the use of chemical methods, such as biological insecticides, pathological microorganisms, predators and finally, genetically modified organisms. With two control approaches (population suppression and population replacement), GMOs are extremely viable alternatives for vector control. What can be concluded through this bibliographic review is that there are several control methods for different stages of the mosquito's life.
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    Análise de dados georreferenciados via R com a assistência de inteligência artificial: aplicações no estudo do uso e ocupação do solo
    (Universidade Federal de São Carlos, 2023-03-30)
    Souza, Ruth Silva
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    Ferreira, Iuri Emmanuel de Paula
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    https://lattes.cnpq.br/5965827433093415
    Environmental management requires comprehensive analysis of georeferenced data, such as land use and land cover data for informed decision making on environmental issues. In this context, GIS programs stand out, allowing the manipulation, processing, and visualization of georeferenced data. An alternative of growing popularity is the use of the computational statistics platform R, which allows sophisticated analysis for diagnosis of environmental problems, modeling, and simulation. The use of the platform is traditional, code-based, and thus requires the user to have knowledge of R Programming Language, a language of the statistical domain that is still little known in other areas. Recently, the difficulty on the part of the user has been practically eliminated with the help of General Artificial Intelligences, such as ChatGPT. ChatGPT is a language model based on neural networks that allows the construction of code in any programming language, including R, from simple instructions provided by the user. In this paper, it is demonstrated how scripts generated by ChatGPT can assist the analysis of georeferenced land use and land cover data through the Programming Language.
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    Consequências psicológicas vivenciadas por mulheres sobreviventes das torturas praticadas pelos aparatos e agentes do Estado durante o período da Ditadura Militar brasileira
    (Universidade Federal de São Carlos, 2023-03-30)
    Monteiro, Julie Ane Notari
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    Brino, Rachel de Faria
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    https://lattes.cnpq.br/0235133592567485
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    https://lattes.cnpq.br/2875930296414147
    This research project aims to carry out an analysis of the psychological consequences that torture brought to women who were political prisoners during the period of the Brazilian Military Dictatorship, which occurred between the years 1964 and 1985. To this end, semi-structured interviews were carried out with women who have suffered such violation. The starting hypotheses were that these women may have experienced impacts on the establishment and maintenance of emotional bonds and loving relationships, difficulties in building a healthy sexual life and development of psychopathologies, such as Post-Traumatic Stress Disorder (PTSD), Generalized Anxiety Disorder (GAD) and Major Depressive Disorder. As a form of analysis, Content Analysis was used based on the participants' reports. Such data analysis confirmed the hypotheses raised by the initial project: women had impacts on the establishment and maintenance of emotional bonds and loving relationships, difficulties in building a healthy sexual life and development of psychopathologies, such as Post-Traumatic Stress Disorder (PTSD), Generalized Anxiety Disorder (GAD) and Major Depressive Disorder. Future studies should cover a larger portion of the population that also suffered during this period: LGBTQIA+ people, black people and the indigenous population. Furthermore, it is extremely necessary to investigate how torture and violation of Human Rights have been validated by the State today.
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    Diversidade molecular de fatores de virulência em amostras de Staphylococcus aureus isoladas de lesões de pé diabético
    (Universidade Federal de São Carlos, 2023-03-30)
    Lima, Marlon Breno Zampieri
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    Pranchevicius, Maria Cristina da Silva
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    https://lattes.cnpq.br/4772148921558977
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    https://lattes.cnpq.br/1091004258752864
    Diabetes mellitus is a highly prevalent disease in the current human population, which can lead to complications such as diabetic neuropathy and peripheral vascular disease; both are risk factors for the appearance of diabetic foot lesions, which in turn can be aggravated by polymicrobial infections of which the Staphylococcus aureus species is one of the main and most frequent microorganisms present. The present study aimed to analyze genes of common virulence factors in S. aureus (n = 25), isolated from wounds on the feet of patients with diabetes at Hospital Geral de Palmas, Tocantins. The virulence genes (fnbA, fnbB, clfA, clfB, sasX, hlA, hlB, hlgCB, seA, seB, seD, seI, seH, etA, etB, etD, lukED, LukPV, EDIN, arcA, Agr I, Agr II, Agr III and Agr IV), biofilm (icaA, icaB, icaC and icaD) and capsule (cap5 and cap8) were detected by conventional PCR assays. Assay results indicated the presence of TSST genes in 14 samples (56%); arcA in 10 (40%); clfB and etA in 9 (36%); icaA in 8 (32%); cap5 and LukPV in 6 (24%); icaD in 5 (20%); LukED in 4 (16%); seI in 3 (12%); Agr II and hlB in 2 (8%) and Agr I, hlgCB and fnbB in 1 sample (4%). The clfA, etB, etD, fnbA, sasX, hlA, EDIN, seA, seB, seD, seH, icaB, icaC, Agr III, Agr IV and cap8 genes were not detected. Of the 25 samples, 6 showed no amplification for any gene, and one sample (33A) showed amplification for 11 genes (35% of the total genotyping panel). The sample 11A presented a genetic configuration compatible with that described in the literature for the clonal marker of USA300. Samples 33A and 33B showed a composite genotype for icaA+icaD+cap5. The diffuse presence of the toxic shock syndrome gene (TSST) found in several isolates alerts to the increase in the difficulty of treatment its association with multidrug-resistant strains. More studies are needed to understand the pathogenicity of these strains in diabetic foot infections.
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    Reflexões a partir da experiência: Psicologia Escolar e os impactos do fechamento das escolas na pandemia de COVID-19
    (Universidade Federal de São Carlos, 2023-03-30)
    Avelino, Laís Missae Ono
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    Brino, Rachel de Faria
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    https://lattes.cnpq.br/0235133592567485
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    https://lattes.cnpq.br/9515534072802144
    Based on experiences in a public school located in the countryside of São Paulo, this article aims to reflect on the challenges faced in the field of education both before and during the COVID-19 pandemic. School and Educational Psychology is present as a theoretical framework to aid in understanding the chronic challenges faced in Education, as well as the effects of school closures during the pandemic. Before the pandemic, the curriculum taught in classrooms did not align with the contemporary demands of society, as it was based on an outdated school model from a different era. Amid the school closures enforced due to the threat of COVID-19 transmission in educational institutions, the school community faced numerous challenges. The absence of physical and emotional support structures for students during this period can significantly impact the dynamics of relationships when schools reopen.
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    Desenvolvimento de crianças com transtorno do espectro autista por meio do inventário Portage Operacionalizado: opinião das mães
    (Universidade Federal de São Carlos, 2023-03-30)
    Souza, Franciele Araújo
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    Cia, Fabiana
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    https://lattes.cnpq.br/5999108571365402
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    https://orcid.org/0000-0002-0155-3331
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    https://lattes.cnpq.br/9619511609436336
    It is believed that children with Autistic Spectrum Disorder (TEA) may experience developmental delays in different ways, and areas. Thus, the study was entitled the development of children with Autism Spectrum Disorder through the portage operational inventory: mothers' opinion. Having as objectives (a) analyze the motor, linguistic, social, cognitive, and self-care development of children diagnosed with Autistic Spectrum Disorder, according to the mother’s opinion; (b) Understand the signs and diagnosis of children with Autistic Spectrum Disorder and (c) Describe the services and needs of these families. The research design was descriptive and exploratory, and it counted on the participation of three mothers of children diagnosed with ASD, between the age groups of three and five years. For data collection, the following instruments were used: (a) a semi-structured interview script; (b) a Criterion Brazil Questionnaire, and (c) Operationalized Portage Inventory (IPO). All instruments were filled out during a remote interview. Both qualitative and quantitative data were collected: the quantitative were analyzed using percentages, and the qualitative data were analyzed in the form of categories. As a result, it was identified that regarding the development of children with ASD, delay in all areas was identified through the IPO, and language was the one with the greatest impairment, followed by cognitive and motor areas. In addition, the participants indicated signs of ASD between 2 years of age. Regarding the types of signs, speech delay and not responding to a call were mentioned. All participants pointed out that children with ASD received support services, but emphasized the importance of all services being public and free. This study concluded that it is possible to verify signs of ASD in children early, and there are variations regarding different areas of development, but children had deficits in all areas. According to these results, children with ASD must have Early Childhood Intervention as soon as possible, so these deficits would be minimized.
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    Projeto de elementos de uma caixa de redução com um eixo de entrada e dois de saída para o protótipo do veículo da equipe Baja UFSCar
    (Universidade Federal de São Carlos, 2023-03-30)
    Bispo, Lucas Henrique da Silva
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    Moreno, Mariano Eduardo
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    https://lattes.cnpq.br/1307496862518321
    Using a 4wd system in an off road vehicle is of utmost importance to overcome challenging terrain and overcome obstacles. Thus, the implementation of a 4x4 model in the Baja UFSCar team prototype can play an important role in the evolution of the project. However, the engine used in the Baja SAE Brasil competitions has a low power and knowing that the purpose of the project is to stimulate creativity and development of the students, the possible types of transmission that could adapt the vehicle to the 4x4 system were analyzed, so that the important factor for decision was the possibility of manufacturing by the students themselves. The present work aims to design the elements directly involved in the transmission of power from a fixed reduction box for the vehicle prototype of the Baja UFSCar team, so that it enables the transfer of power from the engines to the four wheels. Methodologies exposed in the books on the design of machine elements for shaft sizing, cylindrical and bevel gears will be used, because they are references enshrined in the subject. The design of the new gearbox was based on having minimum yield of 85%, a tolerance of ±0.6% for the actual reduction compared to the desired nominal, for both output axes and allow an assessment of the impact of the mass increase of the 4x2 system when moving to the 4x4 system.
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    Por que não pode celular na aula, mas pode aula no celular? As representações humorísticas dos memes da internet sobre educação na pandemia
    (Universidade Federal de São Carlos, 2023-03-30)
    Araujo, Janaina Alves de
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    Gatti, Márcio Antonio
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    https://lattes.cnpq.br/0369563657842763
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    https://orcid.org/0000-0001-9902-2856
    This work sought to analyze the implications of the Covid-19 pandemic in Brazilian Education during the years 2020 and 2021, with the suspension of face-to-face classes. Using as main methodology the bibliographical review, allied to the documental research (). Internet memes about emergency remote teaching were taken as the research object, based on the hypothesis that they constitute a new discursive genre – capable of translating, in a humorous tone, the representations constructed by the subjects about themes with social impact. The research was divided into three moments, the first of which focused on building a timeline with the events of the pandemic in Brazil based on news and documents; the second containing a historical review of the events that marked the emergence of the Digital Age in the 21st century (CASTELLS, 1999; 2003) (LÉVY, 1999) (BELL, 1977) and, finally, a deepening of the concept of meme (LEAL- TOLEDO, 2017) and the analysis of a corpus of 14 memes.
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    Caracterização de uma cepa do gênero Brevundimonas multidroga resistente, isolada de um paciente na Unidade de Terapia Intensiva, usando sequenciamento completo do genoma
    (Universidade Federal de São Carlos, 2023-03-30)
    Soares, Gabriela Guerrera
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    Pranchevicius, Maria Cristina da Silva
    ;
    https://lattes.cnpq.br/4772148921558977
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    https://lattes.cnpq.br/2222866375818312
    Brevundimonas species have been considered an opportunistic human pathogen that can cause invasive and severe infections in patients with underlying pathologies. In order to increase our knowledge about these pathogens, we conducted in-depth genomic and phenotypic characterization of a Brevundimonas strain isolated from cerebrospinal fluid of a patient admitted in a neonatal intensive care unit. The strain was identified as a member of the genus Brevundimonas based on VITEK-2 system results and 16S rDNA sequence. Whole genome sequencing assembly of Brevundimonas sp. showed a total length of 3,261,074 bp and a G+C content of 66.86%, similar to other species of the genus. Multilocus sequence analysis, Type (Strain) Genome Server, digital DNA-DNA hybridization, and Average Nucleotide Identity (ANI) analyses confirmed that the Brevundimonas sp. studied represents a distinct species, for which we propose the name Brevundimonas brasiliensis sp. nov. In silico analysis detected genes associated with phenotypic characterization, related to resistance to β-lactams (penP, blaTEM-16, blaBKC-1) and aminoglycosides (strA, strB, aac(6’)-Ib, aac(6’)-Il). We also found genes encoding the AcrAB efflux pump that confers resistance to a broad spectrum of antibiotics, including β-lactams, tetracycline, novobiocin and fluoroquinolones. Colistin resistance can be attributed to mutation in qseC (Ile283Leu) and in phoP (Arg81Cis). Double amino acid substitution in GyrA (S83L and D87H), and amino acid substitution in GyrB (Glu466-Leu) may be associated with quinolone resistance. The isolate presented many virulence genes related to biofilm formation, adhesion, invasion, secretion, and that can be relevant to its pathogenicity. Brevundimonas brasiliensis sp. nov. genome contained copies of putative T4SS-type ICEs; putative IME; Tn3-type, and IS3, IS6, IS5, and IS1380-type families, suggesting an important role in the development and dissemination of antibiotic resistance, and pathogenicity of the isolate. Our data can provide a basis for understanding genomic variability, antibiotic resistance, pathogenicity, and dissemination of these resistant strains.
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    Polipropileno modificado com semicondutores a base de prata: compósitos com alta potencialidade contra SARS-CoV-2 e outros patógenos
    (Universidade Federal de São Carlos, 2023-03-30)
    Ribeiro, Lara Kelly
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    Rosa, Ieda Lucia Viana
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    https://lattes.cnpq.br/8086262254116449
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    https://orcid.org/0000-0002-2621-8548
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    https://lattes.cnpq.br/8866728190374698
    The worldwide outbreak of the coronavirus (COVID-19) pandemic and other emerging infections is difficult and sometimes impossible to treat, making them one of the major public health issues of recent times. It is noteworthy that Ag based semiconductors can help to orchestrate several strategies to combat this serious social problem. In this thesis, we present the synthesis of Ag3PO4, α Ag2WO4, β-Ag2MoO4 and Ag2CrO4 and their immobilization in polypropylene in amounts of 0.5, 1.0 and 3.0% (w/w), respectively. Synthesized materials were characterized by XRD, Raman spectroscopy, FTIR spectroscopy, AFM, UV-vis spectroscopy, rheology, SEM and contact angle to confirm their structural integrity. The activity of the composites was investigated against the Gram negative bacteria Escherichia coli, the Gram-positive bacteria Staphylococcus aureus and the fungus Candida albicans. The best antimicrobial efficiency was obtained by the composite with α-Ag2WO4, which completely eliminated microorganisms within 4 h of exposure. The composites were also tested for inhibition of the SARS-CoV-2 virus, showing antiviral efficiency greater than 98% in just 10 min. Furthermore, based on the results of first principles calculations at the density functional level, a plausible reaction mechanism for the initial events associated with the generation of both hydroxyl radicals •OH and superoxide radical anion •O2– on the more reactive surface (110) of the Ag3PO4 semiconductor. The stability of the antimicrobial activity was evaluated, resulting in constant inhibition, even after the aging of the material. The antimicrobial activity of the compounds was attributed to the production of reactive oxygen species by semiconductors, which can induce high local oxidative stress, causing the death of these microorganisms. Ag/PP-based semiconductor composites have proven to be an attractive outlet for providing humans with a broad spectrum of biocidal activity.
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    Variedades e variações linguísticas: relações com os anos iniciais do Ensino Fundamental
    (Universidade Federal de São Carlos, 2023-03-30)
    Campos, Naara Fogaça Antunes
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    Gatti, Márcio Antonio
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    https://lattes.cnpq.br/0369563657842763
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    https://orcid.org/0000-0001-9902-2856
    This study had the objective of conceptualizing what linguistic varieties and variations are, understanding the concepts that go through them and the characteristics of each type of variation, aiming at the possibility of teaching that values the student's culture and fighting against linguistic prejudice. After reaching this initial objective of conceptualization, the themes of linguistic variation and education were related, seeking a pedagogical view of the subject and understanding the need to recognizing the presence of variations in the classroom, and how this is relevant in official documents that govern Brazilian education through documentary research. From this incursion into a basic bibliography about the theme, we sought, through a brief survey with participant observation in an elementary school classroom, to observe the nuances of linguistic variation in this space, witnessing the children's relationships with the language they speak, with the teachers, and with the community that surrounds them. In the end, it was concluded that the subject of linguistic variations still has much to be investigated and discussed for there to be a real recognition of its existence beyond the standard norm, although this can be done when there is respect and understanding on the part of teachers through actions that contemplate the students' singularities.
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    Regulador vegetal influencia o potencial fitorremediador de metal pesado em plântulas?
    (Universidade Federal de São Carlos, 2023-03-30)
    Carvalho, Rafael Miranda de Lima
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    Baron, Daniel
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    https://lattes.cnpq.br/2054014705484176
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    https://orcid.org/0000-0001-9542-9413
    ;
    https://lattes.cnpq.br/2949044626384209
    Cadmium (Cd) is a mineral considered a non-essential heavy metal (HM) and is widespread in the 6 environment due to a range of inadequate anthropogenic activities such as industrialization, 7 urbanization, and unplanned agriculture. In plants, exposure to Cd is associated with a range of 8 morpho-physiological disorders including necrosis in roots, stems, leaves, as well as impairment of 9 respiratory, photosynthetic, enzymatic processes, and increased production of reactive oxygen 10 species (ROS). Phytoremediation is an ecological strategy that uses plants accumulator to stabilize, 11 transfer, or degrade environmental pollutants. Despite the relevance and importance of 12 phytoremediation on a global scale, the literature reports conflicting results on the interaction 13 between botanical genus Solanum species and compounds that stimulate phytoremediation, such as 14 plant growth regulators (PGR). Therefore, we decided to address this research in a previous 15 Scientific and Technological Initiation (STI) experiment, which resulted in preliminary 16 experimental data used for the present monograph written in the scientific format 'short 17 communication'. The null hypothesis (H0) consisted on the use of PGR not reducing the 18 phytoremediation potential of seedlings cultivated with heavy metal presence. On the other hand, 19 the alternative hypothesis (H1) consisted on the use of PGR reducing the phytoremediation potential 20 of seedlings cultivated with heavy metal presence. The data from this manuscript elucidated the 21 ability of the PGR to promote the plant defense against abiotic stresses with antioxidant responses, 22 but do not support the hypothesis of the ability to interfere positively or negatively with the 23 phytoremediation potential.
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    Propagação de rumor em uma população cética em N
    (Universidade Federal de São Carlos, 2023-03-30)
    Higashizawa, Lissa Kido
    ;
    Gallo, Alexsandro Giacomo Grimbert
    ;
    https://lattes.cnpq.br/4037274656833325
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    https://lattes.cnpq.br/8439891778039507
    We consider two models for information propagation in N. In both models, the individuals (one per site of N) have random, independent, and equally distributed radius. At the beginning only the individual at 0 has the information. In the first model, the “firework model”, each informed individual will inform the individuals to its right that are within its radius, in the “reverse firework model”, each individual will get the information from the informed individuals on its left that are within its radius. The necessary and sufficient conditions are already known in the literature about the distribution of radius to have survival (positive probability of having infinitely many informed individuals) in each model. In this dissertation, we will obtain results for the extension of these models when individuals believe the information (get informed) only if they receive it (or take it) from at least 2 informed individuals.
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    Revenimento do aço inoxidável supermartensítico 15Cr: aspectos microestruturais e comportamento de corrosão eletroquímica
    (Universidade Federal de São Carlos, 2023-03-30)
    Souza, Celso Antônio Galbiati e Turazza de
    ;
    Silva, Rodrigo da
    ;
    https://lattes.cnpq.br/3763016865133213
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    https://orcid.org/0000-0002-1381-1334
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    Rovere, Carlos Alberto Della
    The supermartensitic steels are a new class of stainless steels in development and consolidation as commercial products for the oil and gas industry, marked by significant changes in the chemical composition of conventional martensitic stainless steels, such as the reduction of the C content to <0,03 %wt, combined with the addition of Ni and Mo. Recently, new alloys containing higher amounts of Cr have been developed, such as supermartensitic stainless steels 15Cr (or super 15Cr), in order to offer na interesting combination of high mechanical strength, toughness, weldability and corrosion resistence in aggressive environments (high concentrations of chlorides, carbon dioxide, hydrogen sulfide etc.). However, these steels are still little used in the construction of components and equipment in Petrobras operating units, because many of their properties are still reasons for investigation, such as the tempering heat treatment effect on corrosion resistence. In this way, the objectives of this dissertation was characterize the microstructure and evaluate the electrochemical corrosion behavior of a super 15Cr in function of the tempering heat treatment. Futhermore, the characterization of the samples was carried out through optical microscopy (OM), scanning eléctron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and measurement of Vickers hardness. Finally, the anodic behavior of this material in a diluted solution of sulfuric acid (H2SO4) was evaluated by potentiodynamic polarization measurements, the degree of depletion in Cr was determined through the technique of double loop electrochemical potentiokinect reactivation (DL-EPR) and the pitting corrosion behavior was observed by anodic polarization tests in 3,5 % NaCl solution. The results showed that the tempering heat treatments promote the appearance of reverse austenite, which increases the degree of Cr depletion of the material. In addition, there was a tendency for Epitting to decrease with increasing temperature and, despite the increase in the degree of Cr depletion, there was no significant variation in Epitting.
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    Análise da eficiência de sequências de pulso de RMN em baixo campo para avaliar qualidade de molhos de tomate comerciais
    (Universidade Federal de São Carlos, 2023-03-30)
    Moras, Debora Jorge
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    Colnago, Luiz Alberto
    ;
    https://lattes.cnpq.br/4438399441102990
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    Venâncio, Tiago
    ;
    https://lattes.cnpq.br/4438399441102990
    Nuclear Magnetic Resonance is a spectroscopic technique based on the interaction of atomic numbers with nuclear spin (l) greater than zero when in the presence of a static magnetic field (B0) and an oscillating magnetic field (B1). This technique is important in many areas of research and development such as organic, inorganic, analytical and physical chemistry, agrochemical production and development. Additionally, it is mostly employed in the pharmaceutical companies, polymer and food industry, in biochemical and biological research and also in the field of chemistry for characterize the chemical composition of samples to be studied, investigate formulations, analyze mixtures, determine purity of compounds and study kinetics and reaction mechanisms, in addition to characterizing molecules. In this work, some works on TD-NMR applied to food analysis are reviewed and an example of the application of this technique is employed to analyze the quality of tomato sauces, using CPMG and CPMG-90 pulse sequences. In the case of tomato sauces, T2 values were related to the amount of water and viscosity, which can be associated to the quality of the product. For some flavors, such as Bolognese type, it is expected to have pieces of meat in its composition and this increases the viscosity, making the sauce thicker and with a lower T2 value. However, given the heterogeneity of this type of sample, it is important to perform a detailed study about other existent T2 components.
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    Análise da coleta de materiais plásticos no período da pandemia em uma cooperativa de triagem da cidade de Sorocaba
    (Universidade Federal de São Carlos, 2023-03-30)
    Tobaja, Ana Violeta Freire
    ;
    Moris, Virgínia Aparecida da Silva
    ;
    https://lattes.cnpq.br/1101036108950133
    O consumo de recursos naturais e a geração de resíduos plásticos aumentaram de maneira acelerada na segunda metade do século XX e no século XXI, representando um grave problema ao meio ambiente. Com a pandemia da COVID-19, medidas e recomendações foram adotadas para evitar a disseminação da doença, de forma que, em um esforço para conter a disseminação do vírus, produtos poliméricos de uso único foram amplamente utilizados, e diversos estudos ao redor do mundo apontaram preocupação com o aumento dos resíduos plásticos neste período. Nesse sentido, um desafio é a reutilização dos resíduos plásticos, agregando valor aos materiais descartados e reinserindo-os na cadeia produtiva. Para tal, a reciclagem é fundamental, e, no Brasil, as cooperativas de triagem têm grande importância. São as cooperativas que coletam, limpam, separam, armazenam e destinam estes resíduos a empresas que fazem sua reciclagem e os reintegram ao processo produtivo. Além de contribuir para a diminuição de resíduos no meio ambiente, a reciclagem pode auxiliar na redução das emissões de gases de efeito estufa (GEE). Desta forma, este estudo teve como objetivo analisar a coleta de resíduos plásticos durante a pandemia, a fim de verificar se houve aumento, comparando dados de anos anteriores à pandemia e dados do período pandêmico; além disso, o trabalho visa avaliar a contribuição das cooperativas na redução das emissões de GEE, destacando a sua importância no cenário atual. As emissões foram calculadas através de uma metodologia simplificada e da calculadora de emissão de GEE do Projeto ProteGEEr. Os cálculos foram feitos comparando o uso de recursos reciclados e recursos virgens para a produção de novos produtos plásticos. Os resultados apresentaram números significativos para a utilização de materiais recicláveis em detrimento de materiais virgens.
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    Desenvolvimento de uma metodologia para usinagem econômica em um processo de torneamento e mandrilamento em uma indústria não automatizada
    (Universidade Federal de São Carlos, 2023-03-30)
    Pereira, Pedro Paulo Spagnolo
    ;
    Antonialli, Armando Ítalo Sette
    ;
    https://lattes.cnpq.br/4367459395417045
    The hydroelectric sector is considered one of the main sources of electricity generation in the country, given the high production capacity involving this energy matrix, in addition to the great abundance of this resource at the national level. Within an industrial context, the manufacturing of mechanical components for hydroelectric power plants is highly influenced by conventional machining processes, such as turning and boring. In the case of a nonautomated manufacturing model, precisely because of the peculiarities of each project, there is no standard regarding machining parameters, quantity of inserts used, piece geometry, and machining time, factors that are fundamental to determine production times and costs for each component. Thus, in the present work, we aim to identify the main machining parameters used, quantity of inserts used per batch of parts, machining time, and cost in the manufacturing of mechanical equipment for small, medium, and large hydroelectric power plants, with the objective of developing a methodology to determine the economic conditions of machining in terms of maximum production and minimum cost. The parameters studied were pointed out from the data collected regarding the machining protocols of the company for each process operation, as well as the quantity of materials used in past and current fabrications in relation to the study in question. In short, the applied methodology was able to map the machining of the Francis turbine rotor in an analytical way and to determine the real influence of the cutting speed on costs and production time.
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    Análise do fluxo de descarte de resíduos de equipamentos eletroeletrônicos na região de Sorocaba
    (Universidade Federal de São Carlos, 2023-03-30)
    Cardoso, Felipe Flores Martins
    ;
    Moris, Virgínia Aparecida da Silva
    ;
    https://lattes.cnpq.br/1101036108950133
    The disposal of waste electrical and electronic equipment is a highly important topic that has gained increasing relevance in recent years due to its impact on the environment from a sustainability perspective. The purpose of this study is to analyze the flow of waste electrical and electronic equipment disposal in the Sorocaba region through the perspectives of the population, companies, and cooperatives. Data was collected through the use of forms, and a comparison was made between this data and the information found in the literature. The literature was classified using the SWOT methodology, which highlighted the strengths, weaknesses, and opportunities. The main results of the study include the significant gap between the generation of waste electrical and electronic equipment and its proper treatment, as well as opportunities to minimize environmental impacts through awareness. Additionally, this study aims to facilitate the development of plans for the evolution of a sustainable circular economy and the enhancement of waste electrical and electronic equipment disposal issues, while reinforcing the association of Brazilian legislation with the Sustainable Development Goals (SDG).