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Visualização de estrutura de domínios em cerâmicas e nanoestruturas ferroelétricas via microscopia de piezoresposta
(Universidade Federal de São Carlos, 2013-02-27) Gonçalves, André Marino; Eiras, José Antônio; https://lattes.cnpq.br/6653223814715498; https://lattes.cnpq.br/0563057979926309
In this work, the domain structure of a transparent ferroelectric ceramic of (Pb0,79La0,21)TiO3 (PLT 21) was investigated in detail by piezoresponse force microscopu (PFM) and a protocol of measurements and analysis of the piezoresponse for the tridimensional reconstruction of the polarization in ferroelectric domains, including from mono and polycrystalline materials was developed. With this protocol, properties of domains and domain walls of the PLT 21 ceramic and of a PbTiO3 (PT) thin film were investigated. Three types of domains were recognized in the PLT 21 ceramic: domains separated by 180° walls, and domains separated by 90° walls in two scales, one in wich the domains have dimensions of about 1 μm and another with dimensions lower than 100 nm. Classical domain structures of lamellae and herringbones, and even more exotic structures as quadrants could be observed in PLT 21. This last one might suggest the existence of flux closure states of polarization in ferroelectric ceramics. In our knowledge this is the first time that quadrant structures are observed in ceramics. We could also observe in PLT 21 ceramic, ferroelectric domains that run through de grain boundary. Analysis of the reorientation of polarization by applying a localized BIAS field, revealed a strong electromechanical coupling in the sample, with the appearance of new 90° domain structure as a way to compensate local deformations generated by the poling process. The domain structure of the PT thin film revealed grains with monodomain structure and grains with polydomain structure, being the latter preferentially formed by 90° walls. The study of the reorientation of domains in the thin films of PT, showed the formation of a monodomain structure in the majority of the grains after the poling process, what significantly differs from the results of the PLT 21 ceramics. Lastly, thin films of Pb(Fe0,5Nb0,5)O3 (PFN) with good structural, microstructural and electrical properties were produced by radio frequency sputtering (R.F. Sputtering) with different thickness (50 nm 950 nm). The values of remnant polarization and coercive field of the hysteresis loop were 7 μC/cm2 and 70 kV/cm, respectively, which are bigger than many results found in the literature. Ferroelectric local properties were investigated in monolithic thin films (i.e., films that have a single grain in the thickness) of PFN and compared with the properties obtained in polycrystalline thin films of PT.
Conselho escolar e gestão democrática : análise da participação dos conselheiros nas escolas municipais de São Carlos
(Universidade Federal de São Carlos, 2013-02-27) Ramos, Renata Pierini; Conti, Celso Luiz Aparecido; https://lattes.cnpq.br/6967887143687279
The primary objective of this dissertation is to investigate the main factors that affect the participation of school counselors in public schools in São Carlos / SP. To this end, we opted for conducting empirical research in order to produce and analyze data capable of providing greater concreteness to the arguments. Thus, in order to determine the research tools and the universe to be studied, techniques for the gathering, samplings, and analysis of data, were selected. For the gathering of data, a questionnaire was applied to Community Education Managers and school counselors. In order to determine the sample, we opted to cover fifty school units ensuring that all segments represented in the School Board answer the questionnaire. And finally, our analyzes were grounded on studies by authors who discuss the democratic management of public schools as a means of extending citizenship and guaranteeing the right of participation. Our preliminary results indicate that, power relationships present in the in interpersonal relationships, is the main factor that hinders the participation of counselors, followed by bureaucratic aspects, described as a subcategory due to the fact that they are related to the fundamental category mentioned above. In contrast, engagement and knowledge in the field are presented in the research as factors that facilitate the participation of counselors. Thus, the results highlight the need to formulate strategies to minimize the negative factors and leverage them to promote the participation of counselors at the municipal level.
Equação mestra microscópica para o modelo de Rabi
(Universidade Federal de São Carlos, 2013-02-27) Lopes, Iury Nunes; Villas-Bôas, Celso Jorge; https://lattes.cnpq.br/5700887540085418; https://lattes.cnpq.br/5292604811223708
The Rabi model is the most complete one has to describe the interaction between radiation and matter. However, as it is difficult to obtain the exact solution to this model, many of recent atom-field studies have used the Jaynes-Cummings model, which eliminates the "counter rotating" terms from the Rabi Hamiltonian in an approach known as "rotating wave approximation". This approach was very precise to describe many experiments in quantum optics area in the past two decades, especially in the context of cavity quantum electrodynamics, where the atom-field coupling g is very weak compared to the atomic transition frequency ω0 and the cavity field frequency ωc. However, in recent experiments in the context of circuit quantum electrodynamics, the atom-field coupling can be comparable to the atom and field frequencies so that the rotating wave approximation is no longer valid. A first goal of the present work is to examine the validity of the rotating-wave approximation in the context of circuit quantum electrodynamics. We also take into account the dissipation of the system, and to do that we have analyzed two different models: a phenomenological approach where the master equation is derived by adding the free decay of the atom and the field, regardless of the interaction between them, and another microscope, where the master equation is derived by taking into account the interaction between the atom and the field. We then investigate what happens when one has two atoms interacting with the same field in the cavity, considering, for example, the "spontaneous" generation of correlations between the atoms mediated by the field, that is, assuming initially all subsystems (atoms and field) in their ground states, we study the dynamics of correlations generated between the atoms. To quantify those correlations we employ measures as quantum discord and entanglement of formation.
Estudantes negros ingressantes na universidade por meio de reserva de vagas : um estudo sobre processos educativos de construção de identidade negra e pertencimento étnico-racial no ensino superior
(Universidade Federal de São Carlos, 2013-02-27) Oliveira, Juliana Augusta Nonato de; Silva, Petronilha Beatriz Gonçalves e; https://lattes.cnpq.br/3674686178639985
The aims of the present research are to identify the educative process from the university life that helps or damages the construction and the strengthening of the black identity and their African roots, with black students who joined the university by means of the reserved places under the Affirmative Action Program of the São Carlos Federal University. (UFSCar) and to point suggestions that contribute with the Affirmative Action Program on the search of strategies to combat the racism. The research was guided by the following question: Which educational processes, in the university life, do contribute for the construction and strengthening of the black identity and the ethnic-racial, of black students who joined by means of the reserved places? The data was collected through semi-structured interviews with three students that declared to be black, two women and a man from the Pedagogy, Chemical Engineering and Social Sciences courses, who were willing to participate. The data analysis, grounded on the Phenomenology principles, was made by descriptive form. The results showed that the educational processes of construction of the black identity and the ethnicracial belonging begins much before entering the university, with experiences occurred in the family, at school and at the participating in the entities of the Black Movement. In the university life, the educational processes that contribute to the construction and strengthening of the black identity and the ethnic-racial belonging are, in the present study, notedly, the political choice of self-declare black, that allow than to sign up at the university admission processes by means of reserved places; the existence of an affirmative action program that recognize their inequality conditions; the possibility of attend classes about the education of the ethnic-racial relationships and the participation in research groups about the thematic of the education of the ethnic-racial relationships; the living together with black students, veterans or not. The data also showed that the educational processes, in the university life, which damage the construction and the strengthening of the black identity and the ethnicracial belonging are related to curriculum centered on Europe and the relation with teachers and other students, which keeps placements and discriminatory attitudes. Thus, the results point to the need of changes in the curriculum and the permanent dissemination of the purposes and strategies of an affirmative action program with teachers and administrative staff.
O efeito da desintegrina DisBa-01 e do silenciamento da integrina avB3 e na interação de células tumorais e endoteliais in vitro
(Universidade Federal de São Carlos, 2013-02-27) Durante, Araceli Cristina; Araújo, Heloísa Sobreiro Selistre de; https://lattes.cnpq.br/4065824911933203; https://lattes.cnpq.br/5291139246541147
Metastasis depends on several physiological processes such as cell adhesion, transendothelial cell migration and proliferation. These events are mediated mostly by integrins, which are adhesion receptors present on cell surface and responsible for cellextracellular matrix (ECM) binding. Disintegrins are small proteins from snake venoms, known to inhibit integrin action and therefore metastatic events such as transendothelial cell migration. DisBa-01 is a recombinant RGD disintegrin from Rhinoceraphis alternatus venom gland, with high affinity to the v3 integrin and anti-metastatic activity in vivo. Thereby, the aim of this work was to investigate the effect of v3 integrin in cell transendothelial migration and cell adhesion under flow of MDA-MB- 231 tumor cell line using DisBa-01 as v3 integrin antagonist. The 3 subunit was knockdown by 1uL siRNA/ITGB3 and lipofectamine 2000 (Invitrogen) was used as transfection agent. Additionally cell adhesion under flow, transendothelial migration and time lapse assays were performed using MDA-MB-231 cell line (silenced or not) incubated with 10, 100, 500 and 1000nM of DisBa-01. The 3 integrin knockdown and treatments with DisBa-01 at 500 and 1000nM significantly inhibited cell adhesion as well as the transendothelial migration. The interaction between DisBa-01 and tumor cells was visualized only with 1000nM of disintegrin and not silenced cells. Therefore, it is important using DisBa-01 in different cell lines and in vivo to elucidate more aspects of its effects as anti-metastatic drug.
Atividade de linguagem: a criatividade em confluências de planos enunciativos temporais no ensino de produção e interpretação de textos
(Universidade Federal de São Carlos, 2013-02-27) Onofre, Stéfano Grizzo; Onofre, Marilia Blundi; https://lattes.cnpq.br/4908382415301882; https://lattes.cnpq.br/7054502406292879
In this research we discuss the concept of creativity in occurrences of confluences of enunciative temporal plans on textual production exams made for the admission on Brazilian university. To achieve the goal, we considered the following question: occurrences of time category enunciative shifts on the exams are responsible for undermining students texts? Generally, it is attributed to this kind of enunciative shifts only negative values. We try to make more profound this question, defending that only recognizing the enunciative shifts as a problem does not give all the means for Portuguese language teaching and learning context to operate with these occurrences. To sustain our aim we launched the hypothesis that the time category enunciative shifts occur in the space between the error and the creativity, because, on one side, they can present themselves as inadequacies front an established enunciative plan and, on the other side, they can be considered as linguistic movements that show the way the student try to assume his authorship, that means, his search for creativity. We sustain the hypothesis using the Theory of Predicative Operations chart. The theoretical reflection brought us to argue that linguistic temporal marks leave traces of students argumentative choice. This way, we could recognize that the time category enunciative shifts make visible some elements that can value students textual productions. These elements may be useful for the enhancement of the teaching and learning process, considering the linguistic and discursive matters.
Os gastos públicos em agricultura no Espírito Santo: uma análise acerca do Plano Estratégico de Desenvolvimento da Agricultura Capixaba (PEDEAC)
(Universidade Federal de São Carlos, 2013-02-27) Covre, Julyana; Castro, Eduardo Rodrigues de; https://lattes.cnpq.br/5702172673123334; Rodrigues, Rodrigo Vilela; http://lattes.cnpq.br/7066100737307566
Since 2003, the state of Espírito Santo has undergone several changes institutional policies, when there were changes in agricultural policy guidelines state, through the Strategic Plan for Agriculture Capixaba (PEDEAG). The study aims to examine whether, due to the implementation of PEDEAG, a change in the spending pattern of the State and assess the relationship between the evolution of public spending in the state of Espírito Santo and its impacts on agricultural production growth.To achieve this goal, we propose a descriptive analysis of public spending on agriculture and estimation of agricultural production function, in two approaches: using as dependent variable agricultural production of the municipalities and counties of agricultural GDP and as explanatory variables, the land factor , human capital, use of fertilizers, technical guidance, number of tractors and municipal public spending. As a result, it was observed that the State expenditure followed guidelines PEDEAG. And that in aggregate public spending on agriculture municipalities followed the behavior of state spending on agriculture. The production functions estimated proved the positive impact of spending on agriculture in both output value of agriculture, as in agricultural GDP, however the technical guidance presented negative, contrary to expectations. It was also found that the deployment of the poles of fruit, except the poles mango and guava, positively impacted the agricultural GDP.
Influência do contexto ambiental no desempenho motor e cognitivo de crianças frequentadoras de creches
(Universidade Federal de São Carlos, 2013-02-27) Santos, Mariana Martins dos; Rocha, Nelci Adriana Cicuto Ferreira; https://lattes.cnpq.br/8359338135003610
The first years of life are a period of constant changes in child development. The identification of risk factors that may affect the course of development is very important to avoid damage throughout the process. Among the environmental risk factors, stand out low socioeconomic status and low education level, beyond the quality of stimulation that is given to child. The child care centers is an important source of stimulus for child population. Faced with the studies reporting low quality of Brazilian's schools, this thesis aimed to investigate the influence of the school environment in motor and cognitive performance of children 0-3 years old. Looking for evidences about the influence of environmental context on motor and cognitive development of preschoolers, the Studi 1 was done by the literature review. This study allowed the identification that the quality of child care is related with the cognitive development of children in the child care centers. However a gap was identified regarding the influence of the school context in motor development. In view of this was done the Study 2, which compared the performance of motor and cognitive development of children day care centers in the same socioeconomic status. In this study it was found that the cognitive, fine motor and gross motor of children in public schools are inferior to private school children. Considering these results, the Study 3 was conducted to assess the environmental aspects of public and private kindergartens that lead to the differences found. This study confirms the importance of family characteristics such as socioeconomic status, maternal education and paternal education for child development. The quality of the school environment is related to cognitive and fine motor performance. Overall, the studies underscore the importance of quality in stimulating child development and the need for monitoring and stimulation of children attending day care centers.
Avaliação da sustentabilidade de um sistema de produção de cana-de-açúcar orgânica
(Universidade Federal de São Carlos, 2013-02-27) Ariedi Junior, Vagner Roberto; Ferraz, José Maria Gusman; https://lattes.cnpq.br/3851804858390996; https://lattes.cnpq.br/7135459454847589
This work aimed to bring a summary of all the actions and practices of organic farming and differential ecological management in a production system of sugarcane. Extensive literature review, consultation with specialized technical and scientific collections, observations and field inspection, were used. Available information were analyzed, such as documents, diagnoses, reports, primary and secondary data. The results of the actions and practices implemented were positive and beneficial in the environmental, economic and social spheres, unlike those practiced in conventional systems. The evaluated system showed up important and effective in the recovery, conservation and biodiversity maintenance, beyond showed up as minimization instrument of social impacts associated with the sector. The system showed a higher level of sustainability when compared to conventional.
Comportamento do consumidor de alimentos: uma análise do consumo de carnes em São Paulo
(Universidade Federal de São Carlos, 2013-02-27) Raimundo, Lívia Maria Borges; Batalha, Mario Otávio; https://lattes.cnpq.br/1015001063418091; https://lattes.cnpq.br/3771063312428520
The meat production chain is a major agro-industrial chains in Brazil and also in the world. Its survival is fundamentally based on its ability to generate and sustain competitive advantage, resulting in value to the final consumer. The per capita consumption of meat (beef, pork and chicken) is growing up in Brazil, and data show that in last twenty years there has been growth of 81%, achieving 80 kilos per capita in 2007. The studies that seek to understand consumer behavior can be translated into strategies and tactics that increase the competitiveness of the entire production chain, since through the purchase the customer transmits information about quality attributes he desires and its acceptability. This study investigated the behavior of the ultimate consumer of beef, pork and chicken in the city of São Paulo, in order to obtain information that support marketing strategies for companies in the sector. From a review of literature about food consumption behavior, focused on meat consumption, the lifting of national research on the topic, as well as a characterization of the productive chains of the three meats in question, were listed the main variables affecting the consumption of meat products. With this basis, a survey was conducted with 400 individuals in São Paulo, during the months of September, October and November 2012. The sample, stratified and probabilistic, was treated with univariate and multivariate analysis (factor and cluster), which allowed the grouping of similar variables and the investigation of dependence between them. It was observed that the bovine meat is preferred by the consumers, followed by the chicken and pork. For beef and pork, there was no relationship between frequency of consumption and income, which confirms the growing influence of nonprice factors on consumption at the expense of economic variables. The chicken meat was the best rated in the category impact on health, and its nutritional composition is best known by consumers. The principal place of purchase of the three meats consists at the supermarket, followed by the butcher. Five clusters of consumers were characterized with different consumption profiles, the economic, the conventional, the demanding, the moderate and the enlightened, performing at different frequencies for each meat in question. The study contributed as an overview of consumer behavior meat in São Paulo, where can be characterized different consumption profiles for each meat in question. Knowing these profiles becomes important once the consumer is the maintainer agent and the driver of financial trends of the entire production chain.
Estudos sobre a síntese da zeólita Beta na presença de íons fluoreto
(Universidade Federal de São Carlos, 2013-02-27) Franco, Gil César Pereira; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/5346237770905097
One alternative to increase the octane rating of gasoline without the use of toxic or polluting compounds, banned by environmental legislation, is the transformation of linear paraffins of low octane number into branched paraffins of high octane number. This transformation occurs through the use of bifunctional catalysts that perform the isomerization reaction through catalytic dehydrogenate/hydrogenate and acid sites. Nanocrystalline zeolite Beta is an excellent material for these catalysts because it presents strong acid sites and supports metallic sites (to dehydrogenate/ hydrogenate) easily. This work aims the synthesis of zeolite Beta with different crystals dimensions (micrometrical scale) for, in the future, use as a bifunctional catalyst. In the future, these catalysts will be compared to previously studies on the efficiency of catalysts nanocrystalline zeolite Beta based. For this hydrothermal synthesis at 140 °C, it was used a reaction mixture of Si/Al ratio = 12,5 and neutral pH. TEOS was used as a silicon source, aluminum metal as aluminum source, TEAOH as a structural directing agent and fluoride as mineralizing agent. Parameters, such as, aging time temperature, crystallization time, aging system type (opened or closed) and ethanol vaporization through forced ventilation were varied. Typical diffractograms of Beta structure were obtained varying aging temperature materials (31 to 48 °C) in only two days of crystal lization time, furthermore structure characteristic crystal morphology in varied sizes of 2 to 6 μm were obtained. It was found the presence of ethanol prevents formation of Beta structure, acting to prevent TEOS hydrolysis, thus a mass decrease, about 50 %, during aging time is needed.