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Comportamento informacional e mineração textual no Twitter
(Universidade Federal de São Carlos, 2018-09-24) Pinto, Guilherme Franco Silva; Furnival, Ariadne Chloe Mary; https://lattes.cnpq.br/1291482506649810; https://lattes.cnpq.br/1848085408867454
This work aims to explore the information behavior of social media users, on Twitter specifically, at the moment they are searching and sharing information on Copyright Laws and its related subjects. Taking in consideration the social, cultural and economic changes that social media has made possible, this project will explore how the adapted Copyright Laws to digital platforms affect the usability of these platforms, and how its users seek information related to those adaptations. The Twitter API was used to collect the posts (tweets) made on the platform that are about Copyright and its related subjects, such as open licenses, Creative Commons, public domain, etc. Then, using Text Mining analysis in the statistical computing environment R, it was possible to assess and relate the terms and words used on these posts with the most common doubts and questions regarding Copyright. Finally, in this data it was possible to identify instances of information behavior of Twitter users during their interactions with each other and the information available on Twitter.
Mapeamento do processo de nucleação e crescimento do peptídeo beta amilóide pelo complexo luminescente cis-[Ru(phen)2(Apy)2]2+
(Universidade Federal de São Carlos, 2018-09-24) Cali, Mariana Pigozzi; Carlos, Rose Maria; https://lattes.cnpq.br/1589143355309943; https://lattes.cnpq.br/7379451505839507
Amyloid beta (Ab) is a peptide fragment highly prone to aggregation that deposits in the extracellular medium and is directly associated with the development and progression of a number of nervous system diseases, in particular, Alzheimer's disease (AD). With this in mind, the objective of this work is to obtain a luminescent Ru(II) complex capable of mapping in real time the aggregation process of the amyloid beta peptide through light stimulus. The cis-[Ru(phen)2(Apy)2]2+ complex was synthesized for this purpose. The complex showed an intense and wide absorption band covering the region 350 to 600 nm with a maximum of 450 nm (molar absortivity = 9800 mol-1.L .cm-1) and broad emission with maximum at 655 nm, exhibiting a Stokes shift in the order of 4800 cm-1 and phosphorescence lifetime of 129 ns. The interaction of the complex with the Aβ1-40 peptide was analyzed by the luminescent responses of the complex throughout the course of aggregation. Interaction studies through changes in luminescence intensity were conducted. Luminescent images and changes in luminescence lifetimes during the aggregation process were obtained by confocal microscopy using the FLIM technique (Fluorescence Lifetime Imaging). The complex proved to be a good marker for the Ab peptide aggregation process. With the fluorescence lifetimes obtained from the luminescent images, it was possible to evaluate the interaction between the complex and Ab1-40. Ab1-40 images, with samples being prepared without the complex, have an average bi exponential lifetime of 3.5 ns. On the other hand, the images of the complex Ab1-40 have an average tri exponential lifetime of 4.8 ns, with a significant contribution of a third long lifetime of around 7 ns. Once the interaction between the complex and Ab1-40 was confirmed, the possible sites of interaction were investigated. Three fragments of the peptide were studied: Ab1-28, Ab11-22 and Ab29-40. The images of FLIM without and with complex proved to be quite different, as well as their lifetimes. After determining the interaction of the complex with the peptide, the ability of the complex to influence the peptide aggregation process was investigated. Studies of circular dichroism at different stages of aggregation showed a significant difference in the ellipticity of the beta-sheet signals formed throughout the aggregation, suggesting a possible inhibitory effect by the complex. Studies with transmission electron microscopy were also performed with the fragments Ab1-40, Ab1-28, Ab11-22 and Ab29-40. Studies with Ab1-40 in the 1:5 complex:amyloid ratio did not show significant change over the control group. On the other hand, studies in the 1:1 complex:amyloid ratio show smaller aggregates, again highlighting the possibility of an inhibitory effect of aggregation.
Modificação química de poli(ácido láctico) com monômeros vinílicos, por processamento reativo, visando ajuste molecular e sua utilização em blendas poliméricas
(Universidade Federal de São Carlos, 2018-09-24) Rigolin, Talita Rocha; Costa, Lidiane Cristina; https://lattes.cnpq.br/8246109223926480; Bettini, Sílvia Helena Prado; https://lattes.cnpq.br/3687551763124327; https://lattes.cnpq.br/9580513904975670
Poly(lactic acid) (PLA) was modified with maleic anhydride (MA) or glycidyl methacrylate (GMA) in the presence of peroxide to assess the physical and chemical changes of the polymer during the reactive processing. Chemical modification of polymers with vinyl monomers can be seen as a great scientific challenge in order to obtain a material with adjustable physical and chemical properties due to changes in acidity, functionality and molar mass. The type of vinyl monomer (GMA and MA), peroxide (dicumyl peroxide and 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane), pure or dispersed in CaCO3, and the monomer and peroxide concentration used were evaluated through an experimental design. Molar mass and acidity content were analyzed. Maleic anhydride grafting onto poly(lactic acid) (PLA) showed a decrease in the polymer molar mass and an increase in the acid content. However, when GMA is used in the functionalization of PLA, an increase in molar mass is observed with reduction of acidity of the polymer. PLA/PBAT blends were obtained in order to evaluate the efficacy of the chemical modification and the feasibility of the applied use of the modified PLA, either as the compatibilizer for the blend or as the matrix, depending on its molar mass and acidity content, in addition to in situ compatibilization with the different monomers. Oscillatory shear rheological tests and transmission electron microscopy (TEM) were used to evaluate how the different modified polymers performed in the morphology development and rheological properties of these blends. The morphology obtained was predominantly co-continuous and the viscosity ratio between the components predominated over a possible reduction of interfacial tension with the introduction of the vinyl monomers in the system. Results also showed that similar morphologies can be formed with the use of both monomers, GMA and MA, and that the procurement methodology of the blends can be adapted for the different monomers.
Análise do comportamento e planejamento cultural: utopia ou distopia?
(Universidade Federal de São Carlos, 2018-09-24) Rocha, César Antonio Alves da; Laurenti, Carolina; https://lattes.cnpq.br/0100195996020169; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/9158317976738950
The notion of science has undergone continuous transformations throughout history, from the Aristotelian conception of contemplative knowledge to the modern ideal of operative knowledge. The modern perspective on science as knowledge was received with antagonistic expectations in the philosophical sphere. On one hand, what is identified as a Promethean narrative highlights the potentiality of science as a means for the emancipation of humanity and the catalyzing of human progress; on the other, the Faustian narrative represents opposing expectations, alerting to the hazards involved in the employment of science and its by-products to the domain of the natural world. Taken to the extreme, these two tendencies symbolize what, in the literary context, can be identified as the established antithesis between utopia and dystopia. In principle applicable to science in general, this oppositional duality is paralleled in the manner in which the ideas of B. F. Skinner, theoretician of behavioral analysis and proponent of the notion of cultural design, were received. Seen with enthusiasm by some and suspicion by others, Skinner's ideas about the science of behavior in general and the management of life in society in particular have been the subject of controversies still unresolved today. This work aimed at a detailed examination of the affinities of the Skinnerian proposition of cultural planning with the notions of utopia and dystopia, with special attention to possible relations with the second notion, in order to answer the question presented in the title: would cultural design implie utopia or dystopia? As an analytical strategy, the Prometheus-Faustian duality was used as a key to read and examine the Skinnerian text, chapter by chapter, in search of inclinations for each of these tendencies. The path pursuited initially involved an analysis of the Skinnerian view on science, technology and behavioral control; then the target was the theoretical formulation of cultural design; later, it was investigated how the proposition was illustrated by the author in its fictional work, Walden Two; finally, starting from a panorama on the genesis and development of the notions of utopia and dystopia, affinities were probed between the proposal of cultural design and these two notions. The results reveal that it is possible to identify inclinations both to the notion of utopia and to the notion of dystopia, and that the complexity of Skinnerian thought prevents an unequivocal answer to the title question. This result led to a conclusion that proposes a re-reading about the proposal of cultural design that relativizes and conceives it outside the dyad utopia-dystopia. The thesis advanced in this work proposes a parsimonious perspective, which updates the proposition of cultural design in light of contextualist and pluralistic objections, preserving its most auspicious factors, such as the experimentalist attitude, and abandoning its anachronistic traits, such as the technocratic platform. Thus, the proposal of cultural design is conceived as a gradualist effort to test contingency arrangements alternative to those institutional arrangements then in development, focusing on small-scale reforms that prioritize, as far as possible, the controlo of people by people, not as means for radical transformations or the establishment of utopian scenarios.