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Ouvir, contar, reviver e recontar: narrativas de/sobre educadores matemáticos que atuaram no Pacto Nacional Pela Alfabetização Na Idade Certa
(Universidade Federal de São Carlos, 2021-10-01) Vasconcelos, Lívia de Oliveira; Passos, Cármen Lúcia Brancaglion; https://lattes.cnpq.br/2297203444364327; https://lattes.cnpq.br/2650089006681898
I participated in the National Pact for Literacy in the Right Age from 2014 to 2017, which allowed me to follow different phases of this public policy: the mathematical literacy cycle in 2014, the discussion on interdisciplinary practices in 2015, the cooling of actions in 2016 and the closure abrupt of the program in 2017. Mobilized by my experience in the program, I chose it as the study theme. This research was carried out with the collaboration of three Mathematics Educators who worked in the genesis of the PNAIC: Carlos Vianna, Emerson Rolkouski – organizers of the PNAIC mathematics training notebooks – and Antonio José Lopes Bigode, who assumed a consultant role in the organizational dynamics of books. These collaborators gave me narrative interviews, through which they introduced themselves to me, telling how they became Mathematics Educators, describing which paths led them to the PNAIC and which projects they were engaged in at the time they were interviewed. The experiences narrated by them, as well as my own experience in carrying out this research, constitute the phenomenon that I investigate narratively, based on the theoretical contributions of Clandinin and Connelly. My general objective is to understand how the experiences of these three Mathematics Educators culminated in the origin of the PNAIC in mathematics in the way in which the program was presented. I do this through four narratives written by me, based on what was narrated by my collaborators. The first one is supported by the interview with Carlos Vianna, who presented me the challenges of putting different authors to work collaboratively and integrated in the PNAIC. Emerson told how the organizers of the mathematics training books were chosen and revealed how his role in other public policy, which preceded the PNAIC, was an important factor in his being invited to assume the position of organizer. Both Emerson and Carlos mentioned a third Mathematical Educator who, being a renowned name in the production of mathematics teaching material, was called upon by them to act as a consultant in the preparation of training materials: Bigode. Bigode, when telling me about the PNAIC, made an inversion of perspective, showing how the program demanded from the academic community a reinvention both in the way of working and in the way of communicating. In the fourth narrative, I resume the legacies of important Mathematics Educators cited by the interviewees as references that formed them, and whose ideals influenced the decisions they took at the PNAIC: Lydia Lamparelli and Romulo Lins. Finally, I present the thesis I built based on the testimony of my collaborators and the interpretive and analytical process I carried out as a researcher.
Surface modification with polymers as a tool to functionalize fabrics, fabricate graded materials and design interface of composites
(Universidade Federal de São Carlos, 2021-10-01) Albers, Rebecca Faggion; Leite, Edson Roberto; https://lattes.cnpq.br/1025598529469393; https://lattes.cnpq.br/2593926880871365
Tailoring the properties of a material for a target application often depends on combining features of different components. To effectively arrange these components in a material, several methods have been developed to chemically modify surfaces, tuning its chemical composition, morphology and properties. Chemically modifying both organic and inorganic substrates enables the fabrication of coatings, the modification of scaffolds and the modulation of mechanical properties of composites. In this work, chemical functionalization through Atom Transfer Radical Polymerization (ATRP) was explored to fabricate coatings on SiOx substrates and cotton-based wound dressings; modifying scaffolds for the fabrication of 3D polymer-based graded materials; and designing the interface of polymer matrix composites. Conventional ATRP in solution is sensitive to oxygen and often requires lengthy deoxygenation processes of the polymerization mixture. When a zero-valent metal (Mt0) is introduced to the system in surface-initiated ATRP, it acts as a reducing agent, consuming oxygen from the polymerization mixture and enables the grafting of polymer brushes under ambient conditions. Zn0 was used as a reducing agent in Zn0 SI-ATRP to favor a cheap, fast and oxygen-tolerant fabrication of polymer brushes. Chemically different polymers were grafted from SiOx substrates using microliter volumes of polymerization mixture and the applicability of the process was demonstrated by grafting polymer brushes from cotton-based wound dressings. SI-ATRP is also a polymerization method in which the grafting density depends on the distance between the initiator and the reducing agent. Such feature enables the fabrication of materials with a gradient of chemical composition and morphology. A scaffold containing ATRP initiator in its structure was fabricated through free radical polymerization (FRP) of a high internal phase emulsion (HIPE) and functionalized through Cu0 SI-ATRP, yielding single and multiple polymer gradients. Poly(oligoethylene glycol methacrylate) (POEGMA) and poly(N-isopropylacrylamide) (PNIPAM) single gradients and poly(2-Hydroxyethyl methacrylate) PHEMA and POEGMA double gradients were fabricated and investigated through attenuated total refection Fourier-transform infrared spectroscopy (ATR-FTIR) and image analysis of scanning electron microscopy (SEM) images. Moreover, polymers with different functionalities were synthesized through ATRP for the interfacial design of polymer matrix composites. Chemical compatibility between matrix and reinforcing elements enhances mechanical properties of composites, however interfacial architecture also influences the mechanical response of the final material. Interfacial vulcanization between the exposed S of 2D-MoS2 and the polybutadiene block of polystyrene-block-polybutadiene-block-polystyrene (PSBS) leads to the formation of loop-chain entanglements at the interface of the composite. To investigate the transference of stress from the matrix to the reinforcing elements at the interface of such composites, controlled architecture polymers were synthesized through conventional ATRP in solution, grafted to 2D-MoS2 and used as reinforcing elements in PSBS matrix composites. Such composites with interfacial brushes and loops were cyclic tested in tensile mode and revealed how molecular events taking place at the interface during loading and unloading cycles impacts the mechanical performance of polymer matrix composites.
Avaliação da correlação entre propriedades colorimétricas e propriedades físico-mecânicas de madeiras tropicais
(Universidade Federal de São Carlos, 2021-10-01) Aquino, Vinicius Borges de Moura; Lahr, Francisco Antonio Rocco; https://lattes.cnpq.br/2333091200416653; Christoforo, André Luis; https://lattes.cnpq.br/7623383075429186; https://lattes.cnpq.br/5303314880493623
This work aimed to evaluate the use of colorimetric properties (L*, a* and b*) of the CIELAB system and apparent density as estimators of physical and mechanical properties of ten tropical wood species using quadratic multivariable regression models. The models were evaluated following the ANOVA (Analysis of Variance) precepts, as well as the normality of the data. Therefore, analyzes were made of how physical and mechanical properties and colorimetric parameters are related. First, the correlation between colorimetric parameters and physical and mechanical properties was evaluated using the Pearson test. The goodness of fit was measured using the coefficient of determination (R²). In order to understand how physical and mechanical properties and colorimetric parameters are related, linear and quadratic models with an independent variable (L* or a* or b*) were generated. After understanding how the colorimetric parameters are related and verifying the independence between parameters and properties, linear and quadratic models were generated in order to see if the use of quadratic models improves the accuracy of the estimates. After the evaluation of the quadratic and linear models, the quadratic multivariable models were validated with data from nine species and the properties of the tenth species were estimated and compared with the experimental data. After validation, quadratic multivariable models were generated with data from the ten species evaluated and the error of the estimates was evaluated using the models obtained as data estimators in the literature. Additionally, the behavior of apparent density and its relationship with physical and mechanical properties was evaluated throughout the entire evaluation. The result of Pearson's correlation showed that the colorimetric parameters, as well as the apparent density have significance in the correlation, indicating a significant relationship between factors and properties, but with a weak correlation. Quadratic models, compared to linear models, increased the significance of the estimate, except for the L* parameter. The results of the validation models showed that fc0, fH0 and fH90 presented good quality in the fit (R²>70%) using only the parameters. Adding density, EM also arrived in good quality in the fit, indicating the possibility of its use. For the models with data from the 10 species, the estimator models of the properties fc0, fH0 and fH90, Ec0 and EM achieved good quality in the adjustment using only the colorimetric parameters, improving the precision with the addition of the apparent density as an independent variable. The comparison with the data estimated by the models and the experimental values show that it is possible to estimate physical and mechanical properties using colorimetric parameters and apparent density.
Do retorno dos vencidos ao altermundialismo: em busca dos significados do movimento zapatista
(Universidade Federal de São Carlos, 2021-10-01) Oliveira Filho, Marco Aurélio Maia Barbosa; Sanchez, Fábio José Bechara; https://lattes.cnpq.br/6423443695464907; https://lattes.cnpq.br/7223147454723043
En el primer día de 1994, indígenas mexicanos del estado de Chiapas sorprendieron al mundo con un levantamiento armado. Emitieron comunicados a la sociedad civil y esta respondió con grandes movilizaciones. Luego de un corto período de guerra contral el “malo gobierno”, los rebeldes decidieron “silenciar las armas” e innovar las formas de hacer política, se conectaron con diversos sectores civiles nacionales e internacionales para formar un movimiento amplio, cuyos ecos resonaron en iniciativas importantes y sentaron las bases para un movimiento global contra el neoliberalismo. A lo largo de los años el zapatismo dejó de ser una guerrilla clasica para enfatizar el desarrollo de la autonomía territorial, la creación de mecanismos de participación y comunicación inspirados en prácticas comunitarias tradicionales y el uso intensivo de tácticas orientadas a los medios de comunicación, buscando así combatir la opresión y construir desde ya “un mundo donde quepan todos los mundos”. Así, a raíz del surgimiento de los nuevos movimientos sociales, el zapatismo entra en escena como movimiento y expresión teórica de un proceso de reconposición del imaginario político revolucionario que manifiesta el impulso de algunas prácticas y temas, pero que a su vez no dejas de canalizar la emergencia de elementos derivados del saber político y prácticas sociales historicamente subalternizadas y hecho invisibles. Es visible, como señala la literatura, que el fenómeno mexicano abre nuevos horizontes para comprender los procesos sociales en curso en América Latina y en el mundo; como experiencia autogestionada, el zapatismo es un referencial para una parte considerable de los movimientos sociales contemporáneos; como forma de lucha por una sociedad más justa y igualitaria representa, desde una perspectiva benjaminiana, un posible fuego que ilumina el camino hacia el paso de la marcha triunfal de los vencidos. A través del establecimiento de un diálogo constante con perspectivas decoloniales y teorías sociales y políticas de corte libertario, esa investigación busca analizar las variables asociadas al proyecto zapatista de autogobierno y sus consecuencias políticas y sociales. La estrategia de investigación se centra en revisiones de la literatura y análisis documentales críticas. Se pretende, a través de este trabajo, comprender los significados que configuran el zapatismo como un movimiento de vanguardia en el nuevo contexto de la sociedad capitalista y de la reconfiguración de las luchas sociales a favor de una transformación social más amplia.
Papel de um derivado semissintético do [6]-gingerol (SSi6) na morte celular e efeitos antimetastáticos no câncer de mama triplo negativo: estudos in vitro e in vivo
(Universidade Federal de São Carlos, 2021-10-01) Dulcey, Liany Johanna Luna; Cominetti, Márcia Regina; https://lattes.cnpq.br/3725318894555272; https://lattes.cnpq.br/1841833705087719
Nowadays, the development of new drugs/compounds to combat breast cancer is one of the main challenges of this research area. Among the different subtypes of this disease, triple negative breast cancer (TNBC) is considered the most aggressive and the one with the worst prognosis, since it has no specific therapeutic target. In this regard, the development of potential antitumor drug candidates for the treatment of this subtype is a major clinical and research challenge. Thus, in the first chapter of this thesis, the in vitro selective cytotoxic effect of SSi6 on the triple negative breast cell line MDA-MB-231 was shown. Unlike its natural homologue [6]-gingerol (6G), this new compound induced cell death by activation of two processes, autophagy (initial activation upon treatment) and caspase-independent apoptosis (late induction upon treatment), promoted by the generation of reactive oxygen species. This strategy of inducing combined mechanisms of cell death, is an interesting alternative for the treatment of triple negative tumors resistant to drugs that induce canonical apoptosis. Given this promising activity, in the second chapter the antitumor and antimetastatic effects of SSi6 on MDA-MB-231 cells in xenograft models were investigated. First, it was demonstrated that SSi6 does not cause toxic effects in vivo, shown mainly by monitoring the body weight of mice and by hematological and histological parameters. In the orthotopic xenograft model, SSi6 (15 mg/kg) slowed down the growth of the primary tumor, as well as the metastatic progression from axillary lymph nodes to the lungs. Finally, in the second xenograft model with resection of the primary tumor, the SSi6 was confirmed to block the progression of metastases from axillary lymph nodes to the lungs and other visceral organs. Taken together, the results demonstrate that SSi6 is a promising compound to be investigated in other preclinical models, which would allow its future application in clinical trials as a single or complementary therapy for the treatment of TNBC.