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Navegando por Data de Publicação, começando com "2023-03-29"

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    A produção sobre atividades lúdicas no ENEQ
    (Universidade Federal de São Carlos, 2023-03-29) Vicente, Gabriela Freitas Souza; Furlan, Elaine Gomes Matheus; https://lattes.cnpq.br/3179865576965852
    Chemistry is a science that involves advanced knowledge and technologies, however, its mediation is still often surrounded by characteristics of memorizing formulas and concepts, through a traditional teaching methodology. In an attempt to change this scenario in chemistry teaching, teachers, professors and researchers make several proposals through alternative methodologies, and one of them is the use of games and other playful activities. Therefore, the present work is a bibliographical research on the production of playful activities in works published at the National Meeting of Chemistry Teaching (ENEQ), in the period from 2011 to 2021, presenting an overview of the production regarding this theme, through characteristics such as educational levels, areas of chemical knowledge, explored in the abstracts and complete works, as well as the presence of theoretical reference and pedagogical purpose of the playful activity. Through content analysis described by Bardin, the 345 works found were categorized according to their pedagogical purpose, such as content review or development, among other aspects. Therefore, we hope that this work can contribute to a new perspective of activities and research on the playful field in chemistry teaching.
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    Análise e aplicações do algoritmo UMAP para classificação e redução de dimensionalidade de conjuntos de dados com múltiplas variáveis
    (Universidade Federal de São Carlos, 2023-03-29) Calixto, Ariel Semensato; Levada, Alexandre Luis Magalhães; https://lattes.cnpq.br/3341441596395463
    Through many real-life applications, gathering information through real instruments subject to noise and imperfections tends to generate datasets where the number of observed variables and components easily exceeds a number of dimensions where manipulation, clustering and classification of said data into distinct sets based on their similarities becomes either difficult or computationally expensive. An efficient way to preemptively prepare this data for further processing and meaningful representation is dimensionality reduction, a process that transforms a dataset from a high-dimensional space to a low-dimensional space such as the low-dimensional space still retains relevant properties from the original dataset. This work proposes to evaluate the current state-of-the-art and establish, using performance criteria, comparisons between the frequently used dimensionality reduction used today and historically, with the main focus on UMAP, a method that seeks to prioritize the classification of data locally close by means of their characteristics. Results were obtained using different datasets with different properties, in order to obtain relevant metrics on the impact that each characteristic of these datasets has on the final results.
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    Educação Infantil e legislação: reflexões acerca de sua aplicabilidade
    (Universidade Federal de São Carlos, 2023-03-29) Sancigollo, Edilaine; Araujo, Thaise Vieira de; https://lattes.cnpq.br/7417720580937774; Santos, Maria Walburga dos; https://lattes.cnpq.br/2954227254025696; https://lattes.cnpq.br/6561228538606688
    The present work seeks to reflect on the legal foundations for planning the pedagogical practices of teachers in Early Childhood Education, having as references the current legislation that guides pedagogical actions in early childhood education, these documents are the National Curriculum Guidelines for Early Childhood Education and the Criteria for Care in Day Care Centers that respects the Fundamental Rights of Children. To carry out such reflections, it was essential to seek data from professionals in the field of Early Childhood Education, and then an information survey was carried out, using an online form, with eleven Early Childhood Education teachers in the city of Sorocaba. Guided by quantitative and qualitative methodology, the work presents an analysis of the collected data - in order to identify and recognize the rights guaranteed by legal documents, which aim to guarantee a quality education for children from 0 to 5 years and 11 months old.
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    Perfil de estudantes indígenas público-alvo da educação especial nas universidades federais brasileiras
    (Universidade Federal de São Carlos, 2023-03-29) Quezo, Luciane Ipaqueri; Corsi, Adriana Maria; https://lattes.cnpq.br/5553922167803121; Orlando, Rosimeire Maria; https://lattes.cnpq.br/4254571422608459; Balatiponé; https://lattes.cnpq.br/2400990678495430
    The present research has as general objective to trace the profile of indigenous students with disabilities in Brazilian federal universities, covering the type of disability and the federal public administrative category. The specific objective will be to indicate the number of indigenous students with disabilities in federal institutions of Higher Education in 2019. The data are related to the year 2019 and were obtained with access to the microdata of the Higher Education census, collected on the INEP platform. The results point to the existence of a considerable number of indigenous students with disabilities in federal institutions of Higher Education. Based on the analyses, the need to give visibility to these people and the expansion of measures to ensure their permanence in Higher Education is highlighted. Diversity is something real and necessary for the generation of new social knowledge about all the cultures then existing. Thus, this research presents elements for reflection on the theme and points out the need for new studies in this area, being essential, since these are still limited.
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    Scalable and interpretable kernel methods based on random Fourier features
    (Universidade Federal de São Carlos, 2023-03-29) Otto, Mateus Piovezan; Izbicki, Rafael; https://lattes.cnpq.br/9991192137633896; https://lattes.cnpq.br/8136176856567377
    Kernel methods are a class of statistical machine learning models based on positive semidefinite kernels, which serve as a measure of similarity between data features. Examples of kernel methods include kernel ridge regression, support vector machines, and smoothing splines. Despite their widespread use, kernel methods face two main challenges. Firstly, due to operating on all pairs of observations, they require a large amount of memory and calculation, making them unsuitable for use with large datasets. This issue can be solved by approximating the kernel function via random Fourier features or preconditioners. Secondly, most used kernels consider all features to be equally relevant, without considering their actual impact on the prediction. This results in decreased interpretability, as the influence of irrelevant features is not mitigated. In this work, we extend the random Fourier features framework to Automatic Relevance Determination (ARD) kernels and proposes a new kernel method that integrates the optimization of kernel parameters during training. The kernel parameters reduce the effect of irrelevant features and might be used for post-processing variable selection. The proposed method is evaluated on several datasets and compared to conventional algorithms in machine learning.
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    Alternativa à tecnologia de fornecimento de vapor e eletricidade em destilarias de etanol de cana para projetos green field via biogás de bagaço, vinhaça e torta de filtro
    (Universidade Federal de São Carlos, 2023-03-29) Fernandes, Matheus Menezes; Lima, Alice Medeiros de; https://lattes.cnpq.br/0038936541518854; https://lattes.cnpq.br/1999564761381379
    Considering the great relevance and impact that the sugar and alcohol sector has in the national context, with a focus on waste generation and the cogeneration process, it is essential to study technologies that can offer alternatives to the treatment and disposal of this waste. An alternative route was proposed for the cogeneration of thermal and electrical energy in ethanol distilleries, a route that uses the main residues of the process (bagasse, straw, filter cake and vinasse) to produce biogas, which will be used as fuel for the cogeneration system using an internal combustion engine or gas turbine in a first stage and a heat recovery boiler (HRSG) in a second stage. In addition to being used in cogeneration, biogas can go through a purification process, transforming it into biomethane and replacing the diesel oil consumed by machines and trucks used for planting, harvesting and transport. To simulate this technological route, several process parameters and assumptions were adopted that allowed the calculations to be carried out. An economic feasibility analysis of the technology was also carried out, using cost and revenue assumptions, in addition to financial indicators such as Net Present Value (NPV) and Internal Rate of Return (IRR). Several different scenarios and combinations were simulated for the generation of biogas from filter cake, vinasse and also from bagasse and straw to supply the fleet and cogeneration. Supplying the fleet with biomethane produced from biogas is the most financially attractive option. The best results were obtained with the use of 100% of the filter cake and 15% of the vinasse for the production of biomethane capable of supplying the entire diesel demand of the automotive fleet. The alternative cogeneration technology is also attractive (considering technical and environmental aspects), but due to the importation of equipment, investment is high, reducing its competitiveness, although there is a greater export of electricity.
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    Procedimento de ensino de leitura e escrita de sentenças para crianças em idade escolar
    (Universidade Federal de São Carlos, 2023-03-29) Silva, Ellen Cristina Brandão da; Postalli, Lidia Maria Marson; https://lattes.cnpq.br/2748282330028870; https://lattes.cnpq.br/4763130985948629
    The 2016 National Literacy Assessment showed that 57,7% of students in the 3rd year of elementary school don’t have fluency in reading sentences. Based on this, interventions provided by the development and application of teaching procedures for reading and writing sentences can contribute to improving students' learning repertoire, especially in the Covid-19 pandemic scenario. This study aimed to evaluate the recombinative reading and writing of sentences, through a procedure for teaching reading and writing sentences and the organization of stimuli in matrices, in school-aged children. Ten participants from the first to the fifth year of Elementary School I, at a regular school, were selected. Participants were recruited by indication of teachers and coordination. Parents or responsible and participants consented and assented to participation, respectively. The design used was multiple probes across matrices. For teaching and evaluation, matching to sample and constructed response matching to sample procedures were used. Three matrices training were used and the diagonal stimuli of each matrix were selected, three teaching sentences (nine teaching sentences) and the remaining sentences were reserved for the evaluation of recombinative generalization. Three sets of stimuli were used: A – dictated sentences; B – figures; and C – printed sentences. The steps of the general teaching procedure involved: (1) Pre-training; (2) Evaluation of relationships between dictated sentences, pictures, and printed sentences (AB, AC, BC, CB), figure naming (BD), reading (CD) and writing, copying (CE) and dictation (AE); (3) Teaching relations AB, AC, CE, BC, CB, AE, CD and BD with three sentences of a matrix training and (4) Evaluation of AB, AC, CE, BC, CB, AE, CD and BD relations. The results showed that of the 10 students recruited by the school, six were conducted in the teaching procedure. One student concluded Matrix 1, three students concluded Matrices 1 and 2, and two students concluded Matrices 1 and 3. In general, the results indicated that participants improved or maintained high performances in the relationships taught and the number of correct answers in relation to recombined sentences increased, demonstrating that the procedure can contribute to the teaching of recombinative reading and writing.
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    Panorama das capacidades institucionais municipais para a promoção da Governança Ambiental no Estado de São Paulo
    (Universidade Federal de São Carlos, 2023-03-29) Calderan, Andre Mafra; Oliveira, Celso Maran de; https://lattes.cnpq.br/9911833172043700; https://lattes.cnpq.br/1811221064314369; https://orcid.org/0000-0001-6458-279X
    Studies on the perspective of sustainable development fulfill local governance as central to the promotion of this new development paradigm. However, due to several factors, such as the limitation inherent to the capabilities of public authorities in providing answers to the complex range of environmental issues and problems; the recent institutionalization of specific organizational structures for the Environment agenda in the State of São Paulo or their absence, the institutional structures of local governments still seem to lack sufficient power in promoting environmental governance. To understand this scenario, the present work analyzes the panorama of institutional resources for the promotion of environmental governance in the State of São Paulo. The methodological proposal is divided into two parts: in the first, a critical review of the recent literature on environmental governance in Brazilian municipalities was carried out, from which the main paradigms related to the construction of environmental governance in the national scenario were identified from the understanding of the scale of the concept (global, territorial and local). At this stage, the different meanings of the same concept were reported, even if at different scales of understanding they delimit the construction of environmental governance in municipalities through different strategies and instruments; the second part was carried out based on the survey, systematization and analysis of secondary data from the Munic survey (2021) organized by the Brazilian Institute of Geography and Statistics, with the objective of bringing the paradigms evidenced in the construction of the concept of governance closer to the proposed scenario for the State of São Paulo. In this stage, a series of data correlations are developed on the institutional resources of the municipalities and their environmental management structures, which were divided into: i) capability to promote expanded participation; ii) capability to provide resources; iii) policy coordination capability and means of implementation. Throughout the analyses, critical reflections were proposed on the listed resources and the understanding of municipal environmental governance. As main results, it is highlighted, in the first instance, that the promotion of environmental governance in the State of São Paulo finds as its main challenge the limits of the current model of representative democracy itself, which imposes barriers to the legitimation of participatory practices, opening room for manipulation and to clientelistic practices, which reinforce social exclusion. Thus, understanding the institutions beyond their structures, and considering the rules, norms and the modus operandi of the institutions, it is necessary to improve the institutional capability of the municipalities in the sense of environmental democracy, based on the pillars of participation, access to information and justice, to be able to promote environmental governance.
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    Uma contribuição ao processo de rotomoldagem em polietileno
    (Universidade Federal de São Carlos, 2023-03-29) Ribeiro, André Krolman; Antonialli, Armando Ítalo Sette; https://lattes.cnpq.br/4367459395417045
    Rotomolding is the polymer transformation process that currently has the greatest growth space in the industry, however it is still a process that needs studies for its improvement. Technical knowledge is poorly parameterized for this process, resulting in the application of the empirical method to solve various problems and also to improve current techniques. The main advantage of rotational molding is the ability to produce parts without residual stresses, resulting in parts with high impact resistance. The main disadvantage of this process is the high cycle time, and most of the research in the industry is for the reduction of time in the process. a piece that can have large dimensions and weight. Considering this difficulty, a reduced-scale laboratory equipment was built, making it possible to carry out comparative experiments, bringing parameters that can be extrapolated for application in the product’s real scale. Rotomolding molds basically have two types of internal finishing, polished and shot-peened. With two molds, each with these respective finishing, the possibility of difference in processing time between them, due to the difference in internal roughness, was investigated. In this study, it was possible to evaluate the behavior of the rotational molding process and compare, through the analysis of the mold’s internal temperature, the thermal behavior in molds with these two types of surface finishing. The results showed that there is a difference in the behavior of the temperature curve inside the mold, but there is also similarity at a certain point in the process, depending on the stage it is in, showing that the blasted mold requires less processing time. The study also brought understanding about the way that heat acts during the mold heating and cooling process.
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    A pobreza no município de Campina do Monte Alegre - SP: um estudo preliminar para o entendimento de suas raízes históricas
    (Universidade Federal de São Carlos, 2023-03-29) Pedroso, Maria Carolina; Peres, Alice Miguel de Paula; https://lattes.cnpq.br/7474552535211807; https://lattes.cnpq.br/8845128954160371
    Recent data point to a scenario of worsening poverty worldwide and in Brazil, at the same time, there is no consensus on what poverty is and what are its causes. This research, of a preliminary nature, intended to study poverty in the small city of Campina do Monte Alegre located in the state of São Paulo, more specifically in the Southwest region of São Paulo. Through historical-dialectical materialism, our intention was to seek the historical roots of poverty. As a result, we identified in the economic formation of Campina do Monte Alegre the colonial and slavery base, of segregationist character. Data shows that currently ¼ of the population is dependent on Auxílio Brasil, 80% of the population aged to be in the labor market does not have access to formal employment within the municipality, and only 10% of the total area of rural establishments is occupied by family farming. As a more recent process, it was possible to identify that the rural population has been falling and soy production has been growing in the largest rural establishments. We can conclude that the research connects the current poverty of the city of Campina do Monte Alegre, to longer historical processes, which restricted access to property and subjected families and individuals to the domination and exploitation of work.
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    Influência da aptidão aeróbia e da idade sobre variáveis do teste de exercício cardiopulmonar de homens aparentemente saudáveis
    (Universidade Federal de São Carlos, 2023-03-29) Oliveira, Isabela Eduarda Gouveia; Signini, Étore De Favari; https://lattes.cnpq.br/1394058741261696; https://orcid.org/0000-0002-5355-3309; Catai, Aparecida Maria; https://lattes.cnpq.br/5801652590531684; https://orcid.org/0000-0002-4837-3936; https://lattes.cnpq.br/6870642406117062; https://orcid.org/0000-0001-8900-0805
    Introduction: the practice of regular physical exercise favors beneficial changes in several organic systems, mitigating the deleterious effects of aging. The cardiopulmonary exercise test (CPET) allows verifying the responses resulting from the integration of the cardiovascular, respiratory and muscular systems, allowing the extraction of predictive variables of health and physical conditioning such as peak oxygen consumption (V̇O2PEAK), peak heart rate (HRPEAK), peak systolic arterial pressure (SAPPEAK), peak diastolic arterial pressure (DAPPEAK), peak relative power (W/kgPEAK), peak carbon dioxide production (V̇CO2PEAK), peak exhaled minute volume (V̇EPICO), slope of oxygen consumption efficiency ( OUES), slope of the ventilatory carbon dioxide equivalent (V̇E/V̇CO2slope), ratio between the relative increase in oxygen consumption and the relative increase in load (ΔV̇O2/ΔW), oxygen pulse (V̇O2/HR), oxygen consumption in the anaerobic threshold (V̇O2AT) and time required for a 50% drop in the peak V̇O2 reached in CPET (T1/2V̇O2PEAK). Such variables studied simultaneously are important indicators of the integrity and health of these systems and can provide important and complementary outcomes considering the influence of physical exercise and age in the organism. Objective: To investigate the influence of regular aerobic physical exercise and age on the set of variables obtained in CPET simultaneously: V̇O2PEAK, HRPEAK, SAPPEAK, DAPPEAK, W/kgPEAK, OUES, V̇EPEAK, T1/2V̇O2PEAK, V̇CO2PEAK, V̇E/V̇CO2slope, V̇O2AT, ΔV̇O2/ΔW and V̇O2/HR. Methods: Forty apparently healthy men were divided into four groups: young trained group (YTG), young untrained group (YUT), middle aged trained (MTG) and middle aged untrained (MUG). Individuals aged 20-30 years and 50-60 years were considered young and middle-aged, respectively. Individuals who practiced at least 150 minutes of aerobic physical exercise per week for 6 uninterrupted months and with a classification of “good” or above according to the American Heart Association (AHA) for relative V̇O2PEAK and who participated in sports events were considered trained. Individuals who did not meet these requirements and who had a “regular” or lower classification according to the AHA for V̇O2PEAK were classified as untrained. All underwent CPET with a ramp-type protocol on an electromagnetic braking cycle ergometer to obtain cardiorespiratory and metabolic variables. Two-way ANOVA or Student's t test were used to compare groups between groups for variables that did not reach homogeneity, considering a p value < 0.05. Results: The groups had different profiles. In addition to the significant differences observed for the age and training factors as a result of the different levels of aerobic fitness and integrity of the systems, the interaction between the factors observed for the variables V̇O2AT (absolute and relative), W/kgPEAK, OUES and T1/2V̇O2PEAK. For the first two variables, the age factor did not show significant differences between YUT and MUG, while for OUES, this same factor was not significant for any comparison. For the T1/2V̇O2PEAK, the training factor was only significant for the young groups. Conclusion: The age and level of physical activity of individuals directly affect variables related to aerobic fitness and systemic integrity, however, the variables V̇O2AT, W/kgPEAK, OUES and T1/2V̇O2PEAK seem to be affected differently depending on age and the level of physical activity of the individual.
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    Segmentação de vasos sanguíneos utilizando Redes Neurais Convolucionais: visualização e análise de correlação dos mapas de ativação
    (Universidade Federal de São Carlos, 2023-03-29) Galvão, Wesley Nogueira; Comin, Cesar Henrique; https://lattes.cnpq.br/9563440403120931; https://lattes.cnpq.br/3164765403744408
    Convolutional neural networks (CNN) are responsible for advancing the automation of tasks in the field of computer vision, with image classification, object recognition and image segmentation, as it is present in different research and industry areas. In particular, the biomedical area, which makes use of CNNs for segmentation of x-ray images and microscopy of cells and blood vessels. These networks are known to be deep, composed of several layers that extract features, called activation maps, from the images and generate complex models with millions of parameters. Therefore, it is important to develop approaches for visualization and interpretation of the generated activation maps. Furthermore, investigating the degree of similarity between representations can lead to a better understanding of how networks generate their information representations. This study investigates ways to extract representations produced by CNNs and develop methods and tools to visualize activation maps, in addition to calculating and analyzing the correlation of these maps in segmentation networks with different depths. Understanding the degree of correlation among the maps and identifying highly correlated maps can be useful for applying methods that make networks more computationally efficient without decreasing their accuracy. This work also proposes to investigate the degree of correlation and similarity between different maps produced by networks, either by a single network or by comparing networks of different depths. The study carried out found that CNNs produce redundant maps as they get deeper, tending to form blocks of highly correlated maps in the last layers.
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    Responder coordenado sob esquema de Razão Variável (VR) em ratos
    (Universidade Federal de São Carlos, 2023-03-29) Souza, Lucas Codina; Souza, Deisy das Graças de; https://lattes.cnpq.br/4404800720856419; https://orcid.org/0000-0001-6164-174X; https://lattes.cnpq.br/1232929577384501; https://orcid.org/0000-0002-4245-1622
    Cooperation between two or more organisms has been experimentally shown to be susceptible to selection by consequences similarly to individual operant behavior. Previous studies in the Laboratory of Psychology of Learning at UFSCar observed the establishment of temporally coordinated responses as a type of cooperation in pairs of rats and investigated the ways in which responding is distributed under fixed ratio (FR) and variable ratio (VR) schedules of reinforcement with equal parameters (FR10, VR10) and with parametric variations of ratio size (FR). In these studies, the consequence was only produced when the two rats emitted responses that were defined as coordinated, and the schedules generated patterns of coordination that were similar to patterns that were observed with the behavior of individual organisms when they were subjected to the same schedule types and parameters. The individual response pattern of each member of the pair was less regular than the coordination pattern, suggesting that the programmed contingency resulted in the selection of coordinated behavior as an operant unit. These were the first studies that used intermittent schedules to investigate coordinated responding. The replication of typical patterns of responding under other schedules of reinforcement may provide new evidence of cooperation as an operant unit and contribute to verifying the relevance and generalizability of this concept. The present study investigated effects of parametric manipulations of ratio size under a VR schedule on coordinated responses of pairs of rats. The coordination criterion was defined as simultaneous lever pressing (t < 0.5 s) by both animals of each pair. The control condition investigated lengthening the cooperative criterion from 0.5 s (A) to 5 s (B) in an ABABA design under a VR 9 schedule (one of the parametric series values). The study also evaluated the extinction of coordinated behavior and effects of shortening the duration of light that was used as feedback for coordinated responses. The results showed the establishment of an inverted U-shaped function between ratio size and behavior (i.e., rates and proportions of coordinated responses). Independent responses that did not belong to cooperative episodes did not systematically change as a function of ratio size. Manipulating the duration of the interval for coordination resulted in rates and proportions of coordinated responses that were greater at 0.5 s than at 5 s. Extinction led to a reduction of individual and coordinated responding but generated variability between the pairs in terms of the initial effect, which sometimes focused on independent responding and sometimes on coordinated responding. These findings indicate that the coordinated VR contingency more directly favored the selection of coordinated responses than individual responding, generating typical patterns of the operant that were maintained under a VR schedule. The results extend generalizability of the effect of reinforcement schedules on coordinated responses of pairs of rats and highlight methodological aspects that should be evaluated in future research.
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    Dinâmica de cargas em semicondutores para fotoeletrólise
    (Universidade Federal de São Carlos, 2023-03-29) Santos, Ana Maria Sanches dos; Ferri, Fabio Aparecido; https://lattes.cnpq.br/8314629367795792
    The present work aims to study the dynamics of charges in nanostructured iron oxide semiconductors in the hematite phase (α-Fe2O3) and hematite modified with Na1+, Zn2+ and Ta5+ used in the generation of hydrogen through photoelectrolysis, a clean, sustainable approach and renewable for fuel production. Photoelectrolysis takes place in a photoelectrochemical (PEC) cell composed of two electrodes, at least one of which is a photoactive semiconductor, immersed in an electrolyte solution and connected by an external circuit. Hematite is studied in this work for use as a photoanode, where the water oxidation reaction occurs, which is the current bottleneck for hydrogen production due to its greater complexity. Recently, an increase in the efficiency of hematite films modified with tetra and pentavalent elements through the method of polymeric precursors with deposition via spin-coating was observed. This increase was induced by the segregation of these elements preferentially on the grain boundaries of the hematite surface. Seeking to assess whether this effect was due to the route of synthesis or to the type of modifier used (Noxidation > 3+), elements with an oxidation number lower than that of Fe3+ were used, as well as a pentavalent element as hematite modifiers by the described method. In order to determine the effects on the load dynamics caused by each element and the position in which each one acted on the photoelectrode structure, measurements of structural, morphological and (photo)electrochemical characterizations were carried out. Although the elements with oxidation numbers lower than Fe3+ have contributed to the increase in the thickness of the films, it was not possible to conclude from the characterizations carried out where these elements acted in the structure of the films and further analyzes are in progress. However, it was observed that these elements worsen or do not modify (Na1+) the hematite charge dynamics processes while the pentavalent element (Ta5+) is responsible for increasing the charge separation efficiency and the external quantum efficiency, reducing the rates surface and bulk recombination as effects of its segregation on the hematite surface.
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    Análise do perfil de resistência a antimicrobianos de bactérias envolvidas em casos de mastite ovina.
    (Universidade Federal de São Carlos, 2023-03-29) Scabello, Milena Aparecida; Stipp, Danilo Tancler; https://lattes.cnpq.br/2930975168886154; https://orcid.org/0000-0002-9577-2446; https://lattes.cnpq.br/9524016740229067
    In sheep farming one of the main diseases in the productive activity is mastitis. The causal agents of the pathology include bacteria such as: Pseudomonas aeruginosa, Mannheimia haemolytica, corynebacteria, bacteria of the genus Staphylococcus spp., in addition to fungi. The main objective of this work was to evaluate the profile of bacteria in cases of ovine mastitis. Through in vitro isolation of collected samples, and antibiogram tests. It can be seen that in most studies the incidence of mastitis due to Staphylococcus ssp. involved in infectious mastitis. Cases of subclinical mastitis have also been identified with enterobacteria such as Salmonella sp. Characterized as environmental mastitis. The indiscriminate use of antimicrobials causes several problems in the production system, due to the resistance of bacteria, and the ineffectiveness of antimicrobials. The experimental design was carried out by selecting two producers with cases of mastitis in their herd, located in the cities of São Manoel and Botucatu-SP, both classified as humid sub-tropical. 10 animals were separated, which originated 20 samples (right and left ceiling), the samples were collected in sterile flasks, and refrigerated where they were taken to the microbiology laboratory of the UFSCar Lagoa do Sino campus for bacterial identification, and resistance tests to antimicrobials. Two bacteria of the Enterobacteriaceae family predominant in the study were identified, Salmonella ssp., and Escherichia coli. Soon after, the antibryogram tests were performed and the following antimicrobials were used for the study: Gentamicin 120μg, Amoxicillin + Clavulanic Acid 20/10μg, Sulfazotrim 25μg, Ciprofloxacin 5μg, Azithromycin 15μg and Tetracycline 30μg, which presented the following percentages of resistance to a certain bacterium, Salmonella sp.: Gentamicin (11.28%), Ciproflaxacin (22.22%), Tetracycline (77.77%), Azithromycin (88.88), Amoxicillin and Sulfazotrim (both 100%). And Escherichia Coli: Gentamicin (27.28%), Ciproflaxacin (54.54%), Tetracycline (45.45%), Azithromycin and Amoxicillin (both 81.81%), Sulfazotrim (90.90%). The cases of enterobacteria in mastitis indicate that the cause is of environmental origin. It can be said that the bacteria showed multiple resistance, there is more than one antimicrobial. Although they belong to the same family of bacteria, Salmonella sp., has a somewhat more aggressive profile than Escherichia coli, and the possibility that the study animals present salmonellosis, causing the antibiotics to have no effect, is not ruled out. Contrasting with the results obtained in the literature, it can be said that subclinical mastitis is prevalent in both cases, thus confirming the thesis that it is necessary to use methods of identifying it, and alternative therapies in the treatment.
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