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Produção de hidrogênio e metano a partir da co-digestão de soro de queijo e glicerol em reator anaeróbio de leito fluidizado
(Universidade Federal de São Carlos, 2021-12-14) Almeida, Priscilla de Souza; Silva, Edson Luiz; https://lattes.cnpq.br/9720274214573371; https://lattes.cnpq.br/1732909136264562
Cheese whey and glycerol are by-products of the dairy and biodiesel industry, respectively. Both by-products are highly produced and can be used in the anaerobic digestion process for energy generation due to their high organic content. The adoption of two-stage anaerobic digestion associated with the application of co-substrates brings several advantages, such as increases in COD removal and production of H2 and CH4. In this context, the objective of this research was to evaluate the co-digestion of cheese whey and glycerol in an anaerobic fluidized bed reactor (AFBR) using a two-stage process, and to verify the effect of organic loading rate (OLR) and temperature on the production of H2 and CH4. Thus, the co-digestion was performed in a thermophilic methanogenic reactor (RU-T) by increasing the OLR from 2 to 20 gCOD.L-1.d-1, with a hydraulic retention time (HRT) of 24 h. After the optimal concentration determination, the HRT was decrease from 24 to 20 and 16 h. For the two-stage process, the OLR of the acidogenic reactor (RA-T) was increased from 60 to 120 gCOD.L-1.d-1 (HRT 4 h) and of the methanogenic reactor from 2 to 20 gCOD.L-1.d-1 (HRT 24 h). Besides, the effect of temperature was investigated in the second stage using a thermophilic (RS-T) and a mesophilic (RS-M) methanogenic reactor. RU-T showed the best performance in the OLR of 10 gCOD.L-1.d-1, with methane yield (MY) of 253.0 NmL CH4.gCOD-1rem and methane production rate (MPR) of 3.2 L CH4.L-1.d-1. In the HRT evaluation, the HRT of 20 h provided the maximum MY of 292.5 NmL CH4.gCOD-1rem, while the maximum MPR was observed in the HRT of 16 h (5.1 L CH4.L-1.d-1). Acetic and propionic acid were the dominant metabolites. Regarding the two-stage process, the RA-T provided a yield of 1.7 mmol H2.gCOD-1app and hydrogen production rate of 3.9 L H2.L-1.d-1, both in the OLR of 90 gCOD.L-1.d-1, with butyric and acetic acid as main metabolites. RS-M produced the highest MY and MPR, equal to 273.2 NmL CH4.gCOD-1rem and 5.8 L CH4.L-1.d-1 in the OLR of 20 gCOD.L-1.d-1. The RS-T showed MY of 269.9 NmL CH4.gCOD-1rem in OLR 10 gCOD.L-1.d-1 and MPR of 4.4 L CH4.L-1.d-1 in 20 gCOD.L-1.d-1. Acetic and isobutyric acid were the main metabolites. Through sequencing analysis, was identified as dominant genus in RA-T Themoanaerobacterium. Archaeas of the genus Methanobacterium was the most abundant in RS-M and RU-T, while the genus Methanothermobacter was in RS-T. In general, it is verified that OLR above 10 gCOD.L-1.d-1 was harmful to RU-T and RS-T, while RS-M showed stability at 20 gCOD.L-1.d-1. The two-stage process showed better performance, however, considering the results of the HRT evaluation in the RU-T, there is the possibility of applying smaller HRT in the second stage for higher CH4 production.
Desenvolvimento e avaliação inicial de um jogo educativo para avaliação de comportamentos pré-aritméticos
(Universidade Federal de São Carlos, 2021-12-14) Gris, Gabriele; Souza, Sílvia Regina de; https://lattes.cnpq.br/8722504383832001; Carmo, João dos Santos; https://lattes.cnpq.br/1263046410329694; https://lattes.cnpq.br/8755049883436369
Some difficulties faced by Brazilian students in Mathematics may reflect insufficient learning from the first years of schooling. Assessment instruments developed systematically and thoroughly can contribute to the mapping of basic repertoires. This work aimed to develop an educational game to assess pre-arithmetic behavior in children at the beginning of school education. Chapter 1 aimed to identify and operationally describe the predictors and indicators of success in arithmetic through a systematic literature review. We reviewed 13 studies - 11 longitudinal and two cross-sectional - and identified 31 predictors and 15 indicators of success. We observed large conceptual and operational dispersion, and it was not possible to identify a consensus on basic skills that are important for later learning in arithmetic. After reviewing developmental studies, we conducted a systematic literature review with an emphasis on behavior-analytic production. Chapter 2 aimed to identify the main characteristics of studies in Behavior Analysis that investigate pre-arithmetic repertoires and discuss the adequacy of the concept of pre-arithmetic skills. Twenty-one studies were included for analysis, divided between studies on numerical conceptual behavior and curriculum proposals that mainly cover relations between numerals and sets. We also discuss the adequacy of the concept of pre-arithmetic skills and propose that the set of studies identified be named "pre-arithmetic behavior". After revising the first two chapters, we operationalized an educational game's tasks to evaluate pre-arithmetic behaviors and collected validity evidence based on the content of Korsan: Pre-Arithmetic (Chapter 3). After grouping and applying inclusion and exclusion criteria, 74 objective-behaviors remained that were translated into game tasks. Semantic, usability, and engagement analysis were conducted with two participants (8 and 10 years old). Content analysis was also performed after consulting three experts. Subsequently, it was evaluated the alignment between proposed in-game tasks and Base Nacional Comum Curricular based on the analysis of four experts. In the experts' evaluation, the game content is considered appropriate for evaluating pre-arithmetic repertoires. We identified the need to change the visual and wording aspects of the instructions to fit the target audience best. In study 4, we collected evidence to refine the instrument by mainly applying the game to a younger target audience. Seven children, aged between 4 and 8 years old, participated in the study. As anticipated by experts in the challenge level analysis, we identified tasks of different difficulty levels, one of the components in the alignment assessment. Adjustments are suggested so that the game works as a suitable assessment tool while also fulfilling good games' engagement and fun goals.
Análise de recursos audiovisuais utilizados por docentes do ensino superior nas disciplinas de Libras
(Universidade Federal de São Carlos, 2021-12-14) Fornari, Rodrigo Vecchio; Santos, Lara Ferreira dos; https://lattes.cnpq.br/7312070448044165; https://lattes.cnpq.br/7411901183805783
The Brazilian Sign Language is a visual-gestural language, and its learning takes place mainly through the visual channel. Therefore, the audiovisual resources present in didactic materials for the teaching of Libras in undergraduate courses must prioritize image and content quality. A few years ago, recording, editing, and sharing a video was only possible for communication professionals or those directly linked to the audiovisual market. Today, thanks to advances in technology and the popularization of smartphones and personal computers, these tasks are performed by “ordinary people”, requiring only a little interest and curiosity to achieve these feats. However, this intuitive use of equipment and tools for video production can cause technical problems that affect the final quality of these materials. In view of this, this research aims to analyze audiovisual resources for the teaching and learning Libras as a second language (L2) for hearing students. For this purpose, it was decided to carry out a exploratory-descriptive research, with analysis of materials produced and/or used by teachers of Libras, of intermediate or advanced level, of the presential courses of licentiate and baccalaureate that aim at the formation of teachers, translators, and sign language interpreters, from Federal Educational Institutions. The professors at these institutions were contacted and, through an online form, an attempt was made to outline the profile of the participants. Interviews were carried out with some participants, aiming at a better understanding of the process of elaboration or choice of audiovisual materials. Subsequently, they were asked to send or indicate the audiovisual material used for analysis purposes. The material collected was presented in the analysis and the discussions and reflections are based on the literature in the areas of visuality and technology. As a result, this research demonstrates the need for technical support and complementary training aimed at these teachers to produce materials with audiovisual resources for their classes, resources that are extremely relevant for hearing learners. The technical analysis of the materials sent allowed the formulation of guidelines and recommendations for capturing, editing, and sharing videos to produce new, more efficient, and assertive materials for the Libras disciplines.
Circuitos curtos de comercialização de alimentos: a conquista de territórios para agroecologia no Triângulo Mineiro
(Universidade Federal de São Carlos, 2021-12-14) Souza, Fernando Cesar de Oliveira; Marjotta-Maistro, Marta Cristina; https://lattes.cnpq.br/3987280258617095; Borsatto, Ricardo Serra; https://lattes.cnpq.br/5988987575101933; https://lattes.cnpq.br/1361384641052259
Faced with the prevailing scenario of a globalized agri-food system that operates towards the subordination of peasant agriculture, new markets are built, like the short food supply chains, as a way to reconnect food producers and consumers. This form of commercialization, as well as agroecology itself, has as a principle, antagonistic logics to those prevailing in the current food regime. In this way, peasants have sought to build by means of short food supply chains an alternative towards the achievement of greater autonomy. In view of the above, the objective of this study was to evaluate and discuss the potential of short agroecological food supply chains, as tools of peasant resistance to the corporate agri-food regime, based on a territorial approach. The methodology of the research is composed of the case study of the experience of agroecological baskets "Sowing Agroforestry", in Uberlândia/MG. Data collection instruments were: documentary analysis, participant observation and semi-structured interviews with actors related to the chain. The analysis of the results pointed to the constitution of a territory, from the social relations based on solidarity, mutual acknowledgment, transparency and learning. The chain demonstrated to be a mechanism, strategy and also product of an agroecological territoriality, ratifying the political potential of agroecology in providing counter-hegemonic paths for the constitution of more ethical, fair and sustainable agri-food systems.
Avaliação do potencial tóxico do inseticida Clorantraniliprole e do herbicida Ametrina, isolados e em mistura, em diferentes temperaturas para uma espécie zooplanctônica
(Universidade Federal de São Carlos, 2021-12-14) Lucca, Gisele Maria de; Freitas, Emanuela Cristina de; https://lattes.cnpq.br/8601993745082402; Melão, Maria da Graça Gama; https://lattes.cnpq.br/8342306603661310; https://lattes.cnpq.br/4458964107177458
The objective of this research was to evaluate the effects of the pesticides Chlorantraniliprole and Ametryn, isolated and mixed, on the species Ceriodaphnia silvestrii at two different temperatures and thus, carry out a preliminary risk assessment of these pesticides to Brazilian water bodies. However, comparative tests of the acute and chronic effects of isolated and mixed compounds were carried out with their standard formulation. The results demonstrated that the acute toxicity tests pointed an increase in mortality with increasing exposure time according to the selected compounds. Concerning to the chronic toxicity tests, the herbicide Ametryn significantly reduced the fertility of C. silvestrii females at concentrations from 20 μg L-1 and the insecticide Chlorantraniliprole caused hormetic effects on female fertility in the two lowest concentrations tested (0,02 and 0,04 μg L-1) and significantly reduced reproduction at the concentration of 0,14 μg L-1. In the experiments, combining the methodology of standardized tests using three temperatures (17, 23 and 30°C), the tests were carried out with the cladoceran C. silvestrii after the acclimation period. In acute toxicity tests for the insecticide Chlorantraniliprole, significant effects on the immobility of organisms were observed at low concentrations tested. In chronic tests, there was a hormesis effect at the temperature of 23°C for the concentration of 0,04 μg L-1 and significant reduction in female fertility were found for body length, number of eggs and offspring from the concentration of 0,07 μg L-1 at the three temperatures tested. For the herbicide Ametryn, the results of the acute tests showed a significant effect of temperature on the toxicity of the herbicide Ametryn, at the highest temperature tested (30°C), the average mortality occurred at lower concentrations than when compared to the mean mortality of the lower temperatures (17 and 23°C). In chronic tests, significant reductions were observed in the following parameters: body length, number of eggs and newborns, with emphasis on the temperature of 17°C, where the organisms of C. silvestrii were more sensitive than at the temperatures of 23 and 30°C. Thus, our results show that acclimation can generate significant differences in the toxicity and distribution of the sensitivity of the cladoceran C. silvestrii, indicating the need to incorporate the thermal factor in ecotoxicity tests with tropical aquatic organisms, as well as this environment variable influences biological processes of that species. In the tests with the mixture, in the acute toxicity tests of the active ingredients, the data showed dependent interaction on the dose level from the Addition of Concentration model (CA), with antagonism occurring at low doses and at high doses what was observed was synergism between its components. Chronic exposure also resulted in a dose-dependent toxicity, with antagonism occurring at low doses and synergism at high doses with a change in interaction occurring at a level equal to EC50. Given the above, it is concluded that the pesticides studied, isolated, in mixture and with acclimation at different temperatures caused toxicity in the test organism, representing potential risks to aquatic environments, suggesting more restrictive measures for the use of these compounds to ensure greater protection of freshwater bodies in tropical environments.
Identidades polinomiais graduadas para a álgebra das matrizes triangulares superiores sobre um corpo finito
(Universidade Federal de São Carlos, 2021-12-14) Riva, Evandro; Gonçalves, Dimas José; https://lattes.cnpq.br/1668407948840456; https://lattes.cnpq.br/4157173099755399
Let K be a field of characteristic p and let UTn = UTn(K) be the algebra of n x n upper triangular matrices over K with the usual product a . b of the elements a,b ∈ UTn. In this thesis we describe the set of all G-graded polynomial identities of UTn, where G is any group and K is any finite field. The vector space UTn with the new product [a,b] = a . b - b . a is a Lie algebra, denoted by UTn^(-). We describe the set of all G-graded polynomial identities of UT2^(-), where G is any abelian group and K is any field with characteristic p ≠ 2.
Os pés da memória: uma etnografia sobre as plantas, o gado e o tempo na beira do rio São Francisco
(Universidade Federal de São Carlos, 2021-12-14) Acypreste, Izadora Pereira; Vander Velden, Felipe Ferreira; https://lattes.cnpq.br/7289231173735671; https://lattes.cnpq.br/4279348687162397
This dissertation seeks to discuss, through an approach about plants, cattle and time [tempo], how the life of riverine quilombolas is produced through continuous multispecific engagements. Residents of areas [áreas] along the São Francisco river [beira do rio], the quilombolas of Sangradouro Grande, Croatá, Gameleira and Várzea da Cruz, communities located in the municipality of Januária, North of Minas Gerais, highlight the very importance of the river in the constitution of the landscape, which is also produced by the daily conviviality [convivência] between people, plants and other living beings [viventes]. Therefore, it is through the engagements between people and these other living beings that we can understand the story [estórica] of the constitution of the landscape, which involved, and still involves, several movements, receptions [acolhidas], help [ajudas], among other reciprocal exchanges between humans and non-humans. But this landscape has been changing over time, changes that can be observed from the conviviality with the living beings of the place and against which one can also resist through alliances with each other. Since the plants are deeply intertwined with the way that riverine quilombolas understand their territories, the proposal is to describe these different connections it establishes with the lives of those who, along with them, cohabit along the riverbank. Thus, these “wonderful things” or “lovely things”, as the people on the riverbank say, serve us here not only as a starting point, but also as a common thread that connects the different discussions that make up the thesis. Through this approach, I hope to capture the most sensitive aspects of the way local residents think and relate to their plants [pés], and how, based on this relationship, they conceive and produce other aspects of their lives. In short, I aim to understand what multispecies relationships say about the way of life, the story, the territorialities, and the conviviality that generates bonds of belonging among the inhabitants of these riverine quilombola communities.
Evolução organizativa e alternância de poder a nível estadual no PT, PSDB e DEM entre 2010 E 2021
(Universidade Federal de São Carlos, 2021-12-14) Thomazini, Marlon Baltieri; Braga, Maria do Socorro Sousa; https://lattes.cnpq.br/2311094074614215; https://lattes.cnpq.br/6628555078488448
Este trabajo busca analizar la evolución de la estructura partidaria a nivel estatal de tres partidos políticos brasileños - Partido de los Trabajadores (PT), Partido de la Socialdemocracia Brasileña (PSDB) y Demócratas (DEM) - y su relación con la alternancia de poder de sus presidentes del estado. Para ello, se recopilaron datos empíricos de los tres partidos políticos (órganos del partido) para evaluar cómo cambió la estructura del partido estatal entre 2010 y 2021. Luego, se midió la duración del mandato de sus presidentes estatales en el mismo período. A la luz de la teoría organizativa de los partidos políticos y la literatura brasileña sobre la organización de partidos, el trabajo sostiene que los partidos descentralizados tienden a otorgar mayor autonomía a los presidentes de los estados, lo que permite que los líderes de partidos que ocupan cargos en la presidencia de los estados permanezcan en el poder por más tiempo. Esto se debe al menor uso de recursos institucionales controlados por la dirección central para inhibir los mandatos de los presidentes de estado.