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Manejo da giberela do trigo e manifestação do potencial toxigênico em diferentes sistemas de cultivo
(Universidade Federal de São Carlos, 2024-06-24) Agápto, João Paulo; Jesus Junior, Waldir Cintra de; https://lattes.cnpq.br/2614953467362376; https://lattes.cnpq.br/5699962523528931; https://orcid.org/0000-0002-1391-8609
Wheat Fusarium Head Blight (Gibberella zeae Schwein, Fusarium graminearum) is one of the most important diseases of this cereal worldwide, causing damage to grains in the form of atrophy, weight reduction, and discoloration. Besides yield loss, it also results in grain contamination by mycotoxins, posing a risk to human and animal health. Thus, managing the disease is a significant challenge for global wheat cultivation. No single strategy used in isolation provides satisfactory reduction of disease intensity and mycotoxin concentration under conditions favorable for pathogen development. This study aimed to evaluate the technical feasibility of integrating fungicide, genetic resistance, and silicon in managing Gibberella in irrigated and rainfed production systems. The experiments were conducted using a randomized complete block design with three replications and four treatments, namely: T1 – Fungicide + Potassium Silicate (F + SK) application; T2 – Fungicide (F) application; T3 – Potassium Silicate (SK) application; and T4 – Control (no F and SK application). In all experiments, the incidence, severity, and index of Gibberella, as well as mycotoxin concentration and productivity, were quantified. After performing variance analysis and Tukey's test (p<0.05). It was found that there was no significant difference between treatments for the agronomic variables. For the laboratory variables, T3 was the treatment that provided the greatest reduction in DON concentration, but it did not differ statistically from T1 and T2. It is concluded that the application of potassium silicate (PS) should be further explored for the reduction of DON. The application of PS may be an alternative in integrated management proposals for controlling wheat scab.
Alfabetização nas escolas do campo: atuação de professoras alfabetizadoras em turmas multisseriadas
(Universidade Federal de São Carlos, 2024-06-24) Ferla, Angelina Bigaton; Sisla, Heloisa Chalmers; https://lattes.cnpq.br/9446133131561056; https://lattes.cnpq.br/3180384643080404
Professionals in rural schools with multi-grade classes, present throughout the country, face major challenges in their pedagogical practices, especially in literacy. This research aimed to analyze the challenges and potentials of literacy practices in multi-grade classes in rural schools of a municipality in the state of Mato Grosso, Brazil. The research question was: How do teachers of rural multi-grade classes articulate and organize their literacy practices? A case study was conducted with three professionals who worked in municipal public rural schools in the school years of 2022 and 2023. These professionals taught classes with 1st and 2nd grades in the same classroom. Data collection was carried out through semi-structured interviews, based on Minayo (1994, 2014), Penna (2020), Ludke and André (1986), and Bardin (1979). The investigation discussed the current legislation on literacy and addressed theories related to the teaching of reading and writing, with contributions from theorists such as Soares (2000, 2009, 2021a, 2021b, 2022), Mortatti (2011), and Bagno (2011, 2021). The discussion on rural education was based on Azevedo and Queiroz (2010), Caldart (2012), Arroyo (2011), and Fernandes (2002). The research results were organized into four categories: "Challenges in rural literacy", "Teaching strategies for diversity", "Literacy potentialized in rural multi-grade classes", and "Formative needs based on challenges shared by rural teachers". The research results indicate the need for specific training for working in rural areas. We observed a variety of adapted approaches to the needs of the classes, but with some gaps in relation to the practices recommended in the BNCC and Magda Soares' theoretical orientation for reading and writing skills in the early years of elementary school. Additionally, some limitations of literacy practices were noted due to the use of standardized materials (textbooks). There is also an urgent need for public policies aimed at Rural Education, promoting professional appreciation and pedagogical approaches sensitive to the needs of multi-grade classes.
A teoria da Ação Social de W.E.B. Du Bois: a mensagem negra-africana que surge do "acaso"
(Universidade Federal de São Carlos, 2024-06-24) Santos, Hasani Elioterio dos; Silvério, Valter Roberto; https://lattes.cnpq.br/9421231847055027; https://orcid.org/0000-0003-1715-4535; https://lattes.cnpq.br/6422457630951026; https://orcid.org/0000-0003-1183-7466
This dissertation presents an analysis of W.E.B. Du Bois’s social action theory, which was developed from the end of the 19th century. The study is methodologically close to Gilroy (1993) and Appiah (2014), interpreting Du Bois as part of a “line of descent” from black and African counterculture in modernity. From this, the argument is that Du Bois’s social action theory is different from the classical sociological tradition. Part of the analytical effort of this study, therefore, is the exercise of contrast between sociological theories of modernity and what Gikandi (2005) and Gooding-Williams (2009) classified as “Duboisian modernism”. It appears that theories of modernity explain human actions considering the process of rationalization of the world, interest, econometric motivation, and/or search for integration and social mobility. Du Bois’s social action theory, instead, is based on the principle of “chance” - historical processes that were not predicted, expected, or desired by the actors, such as colonization and the division of the world into racial groups. The study empirically uses a selection of texts written by Du Bois between 1930 and 1947, on Black Cooperativism and Pan-Africanism, which reinforce this interpretation of his social action theory and reconstruct the assumptions of Cultural, Post-Colonial, and African Diaspora Studies.
Avaliação do efeito de microplásticos de tinta spray em órgãos internos de operárias campeiras de Bombus atratus (Hymenoptera: Apidae, Bombini)
(Universidade Federal de São Carlos, 2024-06-24) Boeing, Guilherme Andrade Neto Schmitz; Waldman, Walter Ruggeri; https://lattes.cnpq.br/0616238673458322; https://orcid.org/0000-0002-7280-2243; Abdalla, Fábio Camargo; https://lattes.cnpq.br/7770803221041927; https://orcid.org/0000-0002-1180-8211; https://lattes.cnpq.br/7980973793405832; https://orcid.org/0000-0003-1354-5619
Recent studies have shown the negative environmental effects of spray paints due to microplastics (MPs) and their chemical composition. Photodegradation of these particles can increase the release of additives, including metals in the pigments. Neotropical bumblebees can be exposed to these contaminant particles, which have already been found in honey. Therefore, this study aimed to evaluate the effects of photodegradation on spray paints MPs exposed to different light intensities and exposure times, as well as assess the potential cytotoxicity of these pristine and photodegraded MPs on the columnar cells of the midgut, Malpighian tubules, and hepato-nephrocitic system cells of forager worker bees of Bombus atratus exposed to 50 mg.L-1 of MPs for 96 hours. Pristine microplastics were obtained through paint spraying, then characterized by shape and size. Portable X-ray fluorescence (XRF) and Fourier Transform Infrared Spectroscopy (FTIR) were used to determine elemental composition and polymer type. The MPs were then exposed to different intensities of UV-C radiation and exposure times. The release of potentially toxic elements (PTEs) by the MPs was quantified using an atomic emission spectrometer with microwave plasma. To assess the toxicity of the MPs, we conducted histological and histochemical analyses of the bee tissues. The XRF analysis revealed several elements in both paints, including five PTEs: Manganese, Chromium, Iron, Copper, and Zinc. The particles exposed to the highest UV-C intensity showed significant changes, such as superficial modification, blooming of additives, and surface detachment resulting in voids, altering their area and roundness values in relation to the pristine. Additionally, they exhibited an increase in the release of PTEs, especially Iron, Manganese, and Copper, which exceeded the safe limits set by the National Environment Council of Brazil (CONAMA). The increased release of PTEs is associated with the significant changes observed in the organs of bees exposed to the photodegraded MPs, which showed cellular vacuolization, nuclear condensation, and pyknosis. The release of PTEs from the photodegraded particles contributes to the disruption of the body homeostasis of the studied bees, potentially leading to reduced fitness and alterations in feeding and survival of the species. These findings underscore the importance of understanding the toxicity of environmentally realistic MPs, as plastic composition and weathering conditions can influence particle toxicity.
Satisfação dos consumidores com os serviços públicos: uma análise dos impactos de políticas públicas no setor elétrico brasileiro
(Universidade Federal de São Carlos, 2024-06-24) Verdolin-Benedito, Patricia; Oprime, Pedro Carlos; https://lattes.cnpq.br/9291517431456908; https://lattes.cnpq.br/4108651193248374
Since 2000, the perception of the satisfaction of electricity consumers has been collected and published by the Iasc – Aneel Consumer Satisfaction Index. Aneel, through resolutions, has promoted the customer-focused mentality among distributors and, in addition to encouraging awards, has made ISO9001 certification compulsory in processes directly related to customers. The objective of this study was to survey the policies, guidelines and strategic actions in the Brazilian electricity sector and how they contributed to the establishment of metrics to evaluate the performance of the sector, as well as to understand the impact of government action on the results of the indicators. For this, the data available from the Iasc – Aneel Consumer Satisfaction Index were used, which were submitted to statistical analysis to evaluate its performance. Given the statistical analysis, it was possible to assume as true the initial hypothesis that the implementation of ISO9001 contributed to improving the perception of the quality of services provided.
Modelos Skellam generalizados
(Universidade Federal de São Carlos, 2024-06-24) Gandolfi, Marina; Diniz, Carlos Alberto Ribeiro; https://lattes.cnpq.br/3277371897783194; https://orcid.org/0000-0003-3464-1108; Conceição, Katiane Silva; https://lattes.cnpq.br/5789619620619667; https://orcid.org/0000-0002-2784-6845; https://lattes.cnpq.br/4024335871041646; https://orcid.org/0000-0002-8010-7654
In applied statistics, counting data are often observed in different areas of study. Due to the great diversity of problems that result in these types of data, it is necessary to propose new models. In this work, we propose generalizations of the Skellam distribution, whose support consists of the set formed by integers (positive and negative), aiming to also explore in the context of regression models. For the process of estimating and inferring model parameters, the classical (maximum likelihood method) and Bayesian (Markov Chain Monte Carlo) approaches were considered for comparison purposes. Specifically regarding the Bayesian approach, which was more efficient in the proposals presented here, we used a variant of the Hamiltonian Monte Carlo algorithm, which consists of reformulating Hamilton’s equations by introducing a stochastic component into the gradient equation, deriving the Stochastic Gradient Hamiltonian Monte Carlo algorithm. To illustrate the proposed models, we present the analyzes of data sets referring to two real problems (3 datasets in total): In the first problem, a set of data corresponding to observations of the weekly variation of the Ibovespa score was considered, that is, the price difference, measured in ticks (cents) of the current day in relation to the previous day, in the period between January 2000 and December 2022. The estimated values for the parameter p characterized the data set as inflated with observations -2 (ticks); In the second problem, two sets of data were considered, corresponding to the values of the differences between games won and games lost by teams in the 2022-2023 regular season of the National Basketball Association, in each conference (East and West). The selection criteria indicated the k-MS model with k = −12 as the best adjusted for the Eastern conference, while for the Western conference, the indicated value was k = −38. Given the good results, both the k-MS and the k-IS models proved to be good alternatives to explain the behavior of data with integer values.
Influência das interações entre leveduras e bactérias contaminantes no rendimento da fermentação etanólica
(Universidade Federal de São Carlos, 2024-06-24) Papin, Larissa Ferreira; Andrietta, Silvio Roberto; https://lattes.cnpq.br/5310166650664210; Bastos, Reinaldo Gaspar; https://lattes.cnpq.br/9329363278429665; https://lattes.cnpq.br/8135812516790242
Brazil is recognized worldwide for its pioneering role in integrating ethanol into its energy matrix, produced via fermentation using yeast strains, particularly Saccharomyces cerevisiae, and sugarcane juice or molasses. The industrial production of ethanol in Brazil is characterized by a non-aseptic process, where the must (a mixture of juice, molasses, and water) doesn´t pass through any type of treatment that aimed to eliminate microbial contamination. Due to these characteristics of the fermentation process in Brazil, one of the factors that can influence fermentation yield is bacterial contamination, which tends to have detrimental effects on the process due to competition for nutrients. However, the interaction between yeasts and contaminating bacteria found in the process is not fully elucidated and may not be entirely harmful, with a complex and dynamic synergy related to the metabolites formed. In this context, the present study proposes to evaluate the impact of interactions between yeasts and bacteria on fermentation yield, cell growth, ethanol production, and by-products. For this purpose, mixed fermentations were conducted in semi-synthetic medium between the yeast Saccharomyces cerevisiae and four different contaminants commonly found in the sugarcane industry. Limosilactobacillus fermentum, Lactobacillus helveticus, Lactiplantibacillus plantarum, and Lactobacillus amylovorus were studied at four cell concentrations (105, 106, 107, and 108 cells per mL) in consortium with the yeast. Ethanol, sugars, acetic acid, lactic acid, and glycerol were quantified, in addition to the biomass formed. The research showed that Limosilactobacillus fermentum negatively affected yeast cell growth and fermentation efficiency, while Lactobacillus helveticus, even though not remaining until the end of fermentation, caused a reduction in efficiency, with high levels of lactic acid, exceeding those in the L. fermentum trials. L. plantarum did not demonstrate the positive synergies reported in the literature, while Lactobacillus amylovorus contributed to increased fermentation efficiency and cell growth. The results emphasize the importance of understanding microbial interactions to optimize ethanol production and demonstrate that there are different forms of synergy among microorganisms, influenced by the medium and cell concentration.