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Modelagem matemática para sínteses enzimáticas de biossurfactantes catalisadas por lipases imobilizadas
(Universidade Federal de São Carlos, 2021-07-08) Torres, Alice de Carvalho Lima; Sousa Júnior, Ruy de; https://lattes.cnpq.br/1983482879541203; https://lattes.cnpq.br/3634638433614642
Enzymatic reactions of esterification of fatty acids with carbohydrates generate biosurfactants, products with high capacity to reduce surface and interfacial tensions, applicable mainly in the food, pharmaceutical and cosmetic industries. Mathematical modeling, in turn, can be a useful tool, in its different approaches, for the simulation and optimization of enzymatic processes. Thus, this work was carried out in three distinct steps and aimed at the mathematical modeling of enzymatic processes to produce biosurfactants, making use of the application of phenomenological (semi-mechanistic), neural and fuzzy approaches. The phenomenological kinetic model of Ping Pong Bi Bi was fitted to experimental data. For this, kinetic data of the production of biosurfactants by esterification of oleic and lauric acids with fructose and lactose, using immobilized lipase B from Candida antarctica (CALB-IM-T2-350) and lipase from Pseudomonas fluorescens (PFL) immobilized on octyl-silica (silanized with octyltriethoxysilane), provided by LabEnz-UFSCar, were used. The classic Levenberg-Marquardt parameter fitting method was applied, resulting in a good correspondence between the proposed model and the experimental data. For validation of the semi-mechanistic model, a new set of experimental data was used, showing excellent predictive capacity of the model. Then, neural kinetic models were built using experimental data of enzymatic esterification of xylose with oleic and/or lauric acids, performed using the biocatalyst CALB-IM-T2-350 and CALB derivatives immobilized on Silica Magnetic Microparticles (SMMPs) with octyl groups (CALB-SMMP-octyl) or with octyl groups plus glutaraldehyde (CALB-SMMP-octyl-glu). Using Matlab Neural Network Toolbox, five artificial neural networks (ANNs) were trained, one for each type of biocatalyst and acid, obtaining R-squared values greater than 0.97. As a last effort in neural modeling, two ANNs were fitted (for two of the biocatalysts), each one of them already incorporating, in its inputs, an option referring to the type of acid. The R-squared values, above 0.98, also showed good predictability. Finally, modeling by fuzzy inference systems was studied, using the Neuro Fuzzy Designer tool from ANFIS (Adaptive Network-Based Fuzzy Inference System) of Matlab. Fuzzy models were built for each of the three biocatalysts under study (CALB-IM-T2-350, CALB-SMMP-octyl and CALB-SMMP-octyl-glu), considering as input linguistic variables the type of acid, temperature, reaction time and substrate molar ratio to predict the conversion of the esterification process. Gaussian membership functions and linear output functions were used, in a Takagi- Sugeno’s fuzzy approach. The parameters were fitted by a hybrid parametric optimization method. The results showed that the fuzzy model outputs were very close to the targets, with RMSE values below 0.006. To demonstrate the potential of fuzzy modeling to optimize processes, response surfaces were built for the conversion of xylose as a function of different operating conditions. The fuzzy surfaces indicated that higher values of conversion are reached after 45h of reaction, at temperatures above 50°C and at RMS of 1:0.2 (acid:sugar). Thus, the present work explored, in a broad way, all the capability of mathematical modeling, under different approaches, in the study of enzymatic production of biosurfactants.
Sequência didática como instrumento para a possível promoção do desenvolvimento do engajamento
(Universidade Federal de São Carlos, 2021-07-08) Gomes, Aline Aparecida Miranda; Julio, Josimeire Meneses; https://lattes.cnpq.br/8805879632103815; https://lattes.cnpq.br/5621931077604056
Engagement is a multifaceted construct and its study seeks to trace ways to improve the teaching-learning process. For this, it analyzes the student's development and their interactions with school and pedagogical activities, thus observing facilitating actions for its promotion, as well as their contributions and possibilities for development. The present qualitative, descriptive and bibliographical research, delimited by the question: “How to build a didactic sequence in the teaching of Natural Sciences that is supported by the construct of engagement considering the analysis of a corpus of selected academic works?”. This analysis will be done through the assumptions of the theoretical framework of Content Analysis proposed by Bardin (2011). As a contribution of this research, the construction of a didactic sequence in science education addressing the microorganism content will be carried out and intends to promote knowledge about the engagement construct and activities that promote its evidence.
Processos pioneiros de diferenciação socioespacial urbana no oeste paulista: o caso de São Carlos (1880-1914)
(Universidade Federal de São Carlos, 2021-07-08) Volante, João Pedro; Truzzi, Oswaldo Mário Serra; https://lattes.cnpq.br/5005536921435787; https://lattes.cnpq.br/9498255413322803
During the late nineteenth and early twentieth centuries, the countryside of São Paulo underwent a series of changes resulting from the coffee economy, including: mass immigration, the official Abolition of Slavery (1888) and the pre-urbanization, responsible for characterizing cities as they are today. Due to these historical and economic facts, cities like São Carlos/SP received different groups of people - due to their ethnicity, race, class and occupation -, responsible for occupying the space of a nascent city in different regions according to their social differences. In view of this, this study aimed to investigate, from historical documents, the genesis of social differentiation processes associated with spatial characteristics in the city of São Carlos/SP from 1880 to 1914, due to the end of abolition and the large influx of foreign migrants to the cities there seems to have been a population differentiation within the streets and neighborhoods, due to these differences between the individuals who produce the urban space, modify it and are linked to it. Therefore, we sought to understand, from censuses, tax collection books and maps, issues related to population differentiation in the streets and neighborhoods as a reflection of the socioeconomic profiles of the population. Data were collected from historical documents from the collections of the Fundação Pró-Memória de São Carlos and the Unidade Especial de Informação e Memória (UEIM) at the Universidade Federal de São Carlos (UFSCar). In the end, all the documentation was cataloged based on a documental analysis and a georeferencing software was used to develop cartographic representations of the social differences found.
“Não nasci rodeada de livros, e sim, rodeada de palavras”: experiências de mulheres negras na UFMS
(Universidade Federal de São Carlos, 2021-07-08) Sousa, Nayhara Almeida; Medeiros, Priscila Martins de; https://lattes.cnpq.br/8021362429861754; https://lattes.cnpq.br/3323228102929152
This research aims to understand sociologically the meanings produced by black women, from their experiences as students in undergraduate courses at UFMS, in the period between 2013 and 2018. With this, we seek to interpret the multiple subjective and social effects of these experiences from the context of the implementation of national policies of affirmative action and Law 12.711, 2012. The law, which became known as the "Quotas Law", made it mandatory to adopt quotas with criteria of school origin (public school), race, and income in all federal universities and federal institutes of technical high school education in the country. With the approval of the "Quotas Law", the Brazilian State consolidated and unified what was already a reality in a large part of the public universities, which had been adopting some kind of affirmative action policy since the previous decade. In the case of the UFMS experience, our specific objectives are: a) To understand how black students build their individual and collective experiences of agency within the UFMS. b) To analyze how the UFMS has implemented actions for student access and permanence, within the scope of Law 12.711/2012, with emphasis on its reflections on black women quota holders. This qualitative and exploratory research was conducted through documentary and bibliographic research and interviews to capture the students’ living experiences. Our theoretical and methodological approach is based on the contributions of Postccolonial Studies, Cultural Studies, Black Feminist Epistemology, Cultural Studies and Black Feminist Epistemology.