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Flutuação populacional de artrópodes em cultivos de soja BT e Não-BT
(Universidade Federal de São Carlos, 2021-05-20) Carneiro, Felipe de Sousa; Araújo, Tamiris Alves de; https://lattes.cnpq.br/4224270419293652; https://lattes.cnpq.br/9056456236652711
Transgenic cultivars use containing Bacillus thuringiensis (Bt) technology has increased significantly in recent years in Brazil, especially in soybean. Even if the technology has provided highly beneficial to production systems, the topic is the scene of great discussions and uncertainties related to the effects that Bt toxin cause to natural enemies and other non-target arthropods present in the crops. In the present study, a population survey of arthropods presents in Bt with glyphosate resistance technology and non-Bt without glyphosate resistance technology soybean cultivars was carried out using the beating cloth sampling method, aiming to evaluate the population fluctuation of natural enemies and pests. It was observed from data collection no significant difference between the three species of natural enemies observed in the samplings, however it was evidenced that not only target pests of the Bt technology were affected, but also some species of secondary pests showed significant difference between the treatments, for example the bettle Maecolaspis calcarisera. Therefore, Bt technology proved to be efficient to be used as an alternative strategy in Integrated Pest Management, being selective to natural enemies and mostly affecting only arthropods targeted by this technology.
Apresentação da música não contingente anterior à iniciação de estereotipias vocais em crianças com Transtorno do Espectro do Autismo
(Universidade Federal de São Carlos, 2021-05-20) Molina, Perolayne Bueno; Elias, Nassim Chamel; https://lattes.cnpq.br/4216525883778695; https://lattes.cnpq.br/6593802909497212
Vocal stereotypies have been described in behavioral literature as repetitive responses to any words or sounds, usually maintained by automatic reinforcement, often presented by individuals within the Autism Spectrum Disorder. In several situations, vocal stereotypy can be considered a problem-behavior, as it can harm the learning environment of both those who perform it and those around them. Access to non-contingent music (NCM) has been used to reduce such responses in view of the effective results of this procedure in reducing these stereotyped vocalizations. In contrast to the possibility of accidentally reinforcing unwanted responses through the use of NCM, the implementation of momentary differential reinforcement of zero responses (MDRO) can be useful, avoiding this problem. This research aimed to verify the effects of a procedure that provides access to non-contingent music (NCM) added to a zero-response differential reinforcement (MDRO) procedure in the reduction of vocal stereotypies in two children with ASD, in their home environments . Data analysis was performed in order to compare the frequency of vocal stereotypies under the conditions: (i) LB and (ii) NCM+MDRO. For this, the ABAB Reversal Design was used. The results showed that during the intervention sessions the levels of vocal stereotypies decreased while the engagement in toy manipulation responses increased for both participants. For one of the participants, there was, on average, a decrease in the percentage of time engaged in vocal stereotypies from 74% in LB to an average of 8.6% during the NCM+MDRO sessions; that is, a 65.4% decrease with the introduction of VI. For the other participant, the average total percentages of time engaged in stereotyping in LB sessions was 67% and dropped by almost half to 35.2%. The study discusses the maintenance functions of these decontextualized vocal responses and whether music, as an auditory reinforcing stimulus, when provided in a time scheme, could have altered the Motivational Operations to the engagement of participants in these stereotyped vocal responses.
Determinação de Si e Y em amostras agronômicas por espectrometria de emissão óptica com plasma induzido por micro-ondas
(Universidade Federal de São Carlos, 2021-05-20) Dias, Ellen Aguilar; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045; https://lattes.cnpq.br/0262656205547369
Different demands for analytical responses are presented in agricultural research. In this approach, this dissertation, divided into two chapters, seeks to offer analytical alternatives for plant breeding and fish nutrition projects. In the first chapter, a procedure was developed to determine silicon in plant samples, specifically sorghum (Sorghum bicolor), used in animal feed and bioenergy production. The presence of high levels of Si in the plant can cause damage to boilers used for the generation of bioenergy. As an alternative to the use of HF, usually employed in the digestion of samples for the determination of Si, the use of HBF4 acid and its possible products of reaction were evaluated. Microwave-assisted digestion was used for sample preparation and determination by microwave-induced plasma optical emission spectrometry (MIP OES). Different volumes of HBF4 acid (0.2 mL, 0.5 mL, 1.0 mL and 2.0 mL) were studied, indicating the most appropriate 0.2 mL volume, with 99% recovery in samples previously analyzed by X-ray fluorescence spectrometry (XRF), and 0.03 g kg-1 limit of detection. The digestion with HBF4 showed that about 70% of Si solubilized was found as fluorosilicic acid. Also, the equilibrium conditions of the reactions involved indicated the formation of HF, confirming the need to employ strategies to avoid damage to the components of the equipment. The mass fractions of Si found in the analyzed sorghum samples ranged from 0.67 to 4.57 g kg-1. The second chapter presents the development and validation of a sample preparation procedure for the quantification of Y by MIP OES. It was used as a marker to evaluate digestibility in ingredients, diets, and fish faeces. The developed procedure presented adequate linearity. It was assessed by values of r and r2, evaluated residues, and homoscedasticity. Selectivity was evaluated in the study related to matrix effects, obtaining satifastor results. Precision, which included repeatability and intermediate precision, presented cv < 0.5%. The limits of detection and quantification obtained were 0.60 mg kg-1 and 1.99 mg kg-1, respectively.
Fenologia de frutificação de espécies arbóreas ornitocóricas em nível de população e de comunidade na floresta atlântica do sudeste do Brasil
(Universidade Federal de São Carlos, 2021-05-20) Oliveira, Aline Christina de; Ribeiro, Kelly Fernandes de Oliveira; https://lattes.cnpq.br/2426387883704170; Martins, Valéria Forni; https://lattes.cnpq.br/0686674300788674; https://lattes.cnpq.br/8316271002032533
The maintenance of the community of frugivore birds in a given region strongly depends on the availability of ornitochorous diaspores. In tropical forests with weak climate seasonality, the richness of species fruiting is generally unseasonal due to the weak selective pressure imposed by climate. However, different ornitochorous species may fruit unseasonably along a year or in a seasonal and asynchronic fashion. Therefore, it is important to evaluate phenological fruiting patterns both on the community and the population levels for a better understanding of diaspore availability to frugivore birds. The goal of this study was to test the hypothesis that the availability of ornitochorous diaspores is constant in a Lowland Forest in southeast Brazil on the community level but not on the population level. For this, we used data on seed rain monthly collected along two years in two non-contiguous 1-ha plots and circular statistics. The seed rain of ornitochorous tree species was mainly composed of autochthonous species in the two sampling years. Species richness was constant along the same year and between years, while diaspore abundance varied along the same year and between years. Species composition varied along the same year and was similar between years. The eight most abundant ornitochorous tree species in the seed rain showed long fruiting periods, and seasonal and usually asynchronous fruiting. Last, most of the abundant species did not fruit during the same months in the two sampling years. Our results show that the unseasonal pattern of species richness is composed of non-overlapping seasonal patterns of the different species of the community. Hence, there is availability of diaspores from a constant number of species along the year, but the composition of species fruiting and diaspore abundance change over time. This study shows the importance of individually evaluating phenological patterns of species of a community, as specific patterns might not coincide with the overall community pattern.
A precarização do trabalho docente no ensino superior: análise sobre as implicações do trabalho do professor designado na Universidade do Estado de Minas Gerais
(Universidade Federal de São Carlos, 2021-05-20) Francklin, Adelino; Fernandes, Maria Cristina da Silveira Galan; https://lattes.cnpq.br/5786385589553214; https://lattes.cnpq.br/3243103572002701
The State University of Minas Gerais (UEMG) has had a high number of temporary professors. This research asks: what are the implications of temporary hiring for teaching work at UEMG, Unidade Passos? The objective of the thesis is to analyze the implications of the process of precarious work of temporary teachers at UEMG, Unidade Passos, in the context of the unfolding of neoliberal educational policies, having as reference the concepts of field, habitus and scientific capital, by Pierre Bourdieu. The study is qualitative and uses bibliographic, documentary and field sources. The bibliographic sources were obtained through the website of SciELO journals, Google Scholar, Rede Universitas.Br and the library of the Federal University of São Carlos (UFSCar). Two notices of simplified selection processes (PSS) from UEMG, published in the years 2018 and 2019, were analyzed for the Passos unit. And semi-structured interviews were carried out with 10 professors from UEMG, Passos unit, transcribed by the researcher. For the analysis of the results, the data triangulation technique and the content analysis technique were used. The hypotheses have been partially confirmed. It was not possible to confirm whether the professional habitus of professors appointed in the face of struggles in the scientific field has undergone significant changes. As for the other hypotheses, we confirm that: a) the maintenance of the high number of positions of professors appointed at UEMG is due to the option of the state government to save with the payroll of public servants; b) the maintenance of designated professors causes greater losses for the development of research and extension and the exercise of functions that refer to management; c) the uncertainty regarding the classification in the PSS for the following year becomes an obstacle for the elaboration and approval of new projects, negatively affecting their academic production due to the difficulty of obtaining scholarships and project continuity; d) teaching is also impaired due to the disincentive to prepare good classes. Several elements were found that confirm the precariousness of teaching work, modifying their practices and being able to cause changes in professional habitus, such as low remuneration; job instability; teacher turnover; high number of didactic charges and teaching duties; having to teach disciplines without adherence with their training and preparation of projects in the short term. There is a high rate of teachers who occupy positions with a partial work regime. Participation in UEMG's PSS annually or every two years, causes uneasiness and disputes in the field, to be experienced among teachers. The continuing education of appointed teachers is negatively affected by instability in positions, given that they do not have the right to leave the position for studies. The expansion in the number of UEMG units, increasing the number of students and teachers, was not accompanied by a proper budget increase. As a result, the infrastructure became precarious, the funds for research, extension and student aid were reduced, the reduction of full-time positions and the maintenance of temporary employment contracts.
Efeito do extrato de folhas de mamona (Ricinus communis) sobre a cigarrinha do milho Dalbulus maidis (Delong & Wolcott)
(Universidade Federal de São Carlos, 2021-05-20) Besson, Gabriel Antonio; Araújo, Tamiris Alves de; https://lattes.cnpq.br/4224270419293652; https://lattes.cnpq.br/1944569286285607
Corn (Zea mays L.) has a high productivity potential, however this crop is attacked by a complex of pests which can compromise this productivity. In this context, corn leafhopper (Dalbulus maidis DeLong & Wolcott) is a pest that causes both direct and indirect damage for this crop. For the management of this pest, the application of synthetic insecticides is the main method, however, in order to obtain other alternative control methods that cause less environmental impact, the use of plants with insecticidal activities, such as castor bean (Ricinus communis L.), has been encouraged. Therefore, the objective of this work was to evaluate the effect of castor leaves extracts (ricinin) for controllling D. maidis on corn crops. For this, an experiment in field condition was carried out in randomized block design with 3 replications, to be tested 4 treatments: two treatments of castor extract with concentrations of 10 ppm of ricinine and 100 ppm of ricinine, a positive control based on commercial insecticide Imidacloprid and a negative control based on water. After the corn cultivation reached the VT stage, for a period of 23 days, 14 evaluations were performed by directly counting the number of D. maidis in 5 plants in the central line of each experimental plot. Over this period, there were three treatments applications, on the dates of the 3rd, 5th and 12th evaluations. Significant differences were detected in the mean density of D. maidis per plant among treatments. The castor extracts treatments and the insecticide Imidacloprid obtained similar mean density per plant. It was also observed that not only for the same date (pre and post treatments application) but also over the time, that the treatments with castor extracts and the commercial insecticide reduced the population of D. maidis. According to the results found in the present study, the extract of R. communis has an effect on the corn leafhopper (D. maidis), and therefore, could be considered for the control of this pest.
Efeito da adição de Al e C na evolução microestrutural e no comportamento mecânico de aços austeníticos de baixa densidade com alto teor de Mn
(Universidade Federal de São Carlos, 2021-05-20) Otani, Lucas Barcelos; Zepon, Guilherme; https://lattes.cnpq.br/7924187202036614; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://lattes.cnpq.br/2519980413159984
Low-density steels are advanced materials that are being developed mainly for the automotive industry to reduce the structural weight of cars. The most common studied compositions comprise FeMnAlC variations, in which both the chemical composition and processing route influence the final microstructure. Most of the studies involving the austenitic low-density steels is related to the evaluation of the mechanical properties focusing on the induced plasticity mechanisms. The objective of this thesis is to evaluate the effect of Al and C additions on the microstructural evolution and mechanical behavior of high-Mn austenitic low-density steels. Five systems with different C and Al additions were studied: Fe-36%Mn, Fe-36%Mn-2.5%Al, Fe-36%Mn-5%Al, Fe-33%Mn-5%Al-0.3%C e Fe-30%Mn-5%Al-0.6%C (weight%), in which for the alloys varying the C content, the stacking fault energy (SFE) was kept constant. Theoretical models to predict the SFE, the critical resolved shear stress for the TWIP effect, and the yield stress were used. The SFE of one alloy was determined experimentally through the partial dislocations distance. The ingots were produced by spray forming followed by mechanical processing and heat treatment. It was observed that the aluminum is not effective as carbon to increase the yield stress of the alloy. Only the alloys with C additions presented deformation twins, even though they presented the highest SFE values. The alloy without Al and C additions (lowest SFE in this work) did not presented deformation twins when deformed at room temperature, but at -100°C those structures could be observed after the tensile test. It can be pointed out that mechanisms which anchored the dislocations are important to the occurrence of the TWIP effect in high-Mn low-density steels.