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Modelos miméticos de catecol dioxigenase e catecol oxidase: correlação entre estrutura e atividade catalítica de complexos mononucleares de ferro(III) e binucleares de cobre(II) contendo bases de Schiff
(Universidade Federal de São Carlos, 2014-12-15) Cruz Júnior, José Wilmo da; Dockal, Edward Ralph; https://lattes.cnpq.br/6461328124491559; https://lattes.cnpq.br/7986883288512102
In this work binuclear copper(II) complexes and mononuclear iron(III) complexes were studied as functional mimetic models of enzymes capable of catalyze the oxidation of catechols. Different structures of the complexes were obtained by synthesizing them with different Schiff bases, which possesses imine groups with aliphatic chains containing groups ranging from two to six carbon atoms between the nitrogen atoms, as well as cyclic substituted aromatic species between these atoms. These structures have allowed structural and electronic effects to be evaluated and correlated with the catalytic activity of their complexes. The binuclear copper complexes showed excellent catalytic efficiency in transforming the substrate 3,5-di-tert-butylcatechol to its respective quinone. The kinetic parameters obtained allowed the evaluation of how and which structural effects affect their catalytic efficiencies, being observed an increase in affinity between catalyst and substrate with increasing carbon chain between imines. It was also observed that the presence of substituents in compounds with aromatic diimines causes a lesser affinity between catalyzer and substrate and consequently a low catalytic efficiency. Catalytic assays with the iron(III) complexes have shown that regardless of the structural changes caused, none of them presented activity similar to the enzyme catechol dioxygenase. But those complexes which catalyzed the oxidation of the substrate to its respective quinone, being these changes accompanied for 24 hours of reaction. Although the substrate conversions were slow and low, trends were observed from correlations between structure and catalytic activity. The percentages of 3,5-di-tert-butilquinone obtained for the best catalysts among these complexes suggests that there is a step of forming a catalytically active species during the reaction time.
O campo dos estudos em administração no Brasil pós anos 90: reconfiguração de léxicos e temáticas na produção acadêmica nacional
(Universidade Federal de São Carlos, 2014-12-15) Carvalho, Angela Maria Carneiro de; Grün, Roberto; https://lattes.cnpq.br/6028266827740491; https://lattes.cnpq.br/3860073481051842
The context of the financialization of the global economy and the corresponding world-class organizations have posed major challenges to the 21st century managers. Those responsible for their professional education - including professors and Business Schools - have faced uncertain and complex contexts. The validity of management education programs has been increasingly questioned. This study aims to investigate the changes in the Business Administration field in Brazil after the 90 s; more specifically, it focuses on the knowledge involved in management education and on the agents and their respective institutions that provide this knowledge. This includes specifically the activities of professors and researchers engaged in Master's and Doctoral programs in Business Administration at Higher Education Institutions affiliated with the government agency called CAPES, a foundation whose central purpose is to coordinate efforts to improve the quality of higher education in Brazil. Therefore, this research was conducted based on the analysis of the structure of the field of these professors and researchers in Business Administration in Brazil after the 90 s. Pierre Bourdieu s theoretical and methodological apparatus was used due to the possibility of relational understanding of social space, where the agents - whose power is asymmetrically distributed - occupy and fight over positions. Several studies demonstrate the predominance of American authors in the Brazilian scientific production, which is, therefore, basically functionalist. On the other hand, around the 90 s, the American hegemony became refuted, especially by researchers who started to demonstrate greater intellectual independence to that traditional mainstream epistemology. This emerging group has been inspired by the Critical Management Studies (CMS), originated in the UK. The conclusion of the present study allowed the understanding of part of the oppositions and affinities that organize this field, its transformations, and the strategies of two rival groups of agents, constituting the arena of the organizational studies. On the other hand, although weakly adherent of the 'new entrants' denomination, the changes that took place after the 90 s can be said to be easily identified and often institutionalized. This study also revealed the intensified debates and systematization towards the construction of a particular epistemology of this discipline, which not only contribute to the improvement of the administrative theory, but also provides means to promote the future development of Business Administration.
Utilização de concentrados de eva-argila organofílica obtidos por spray drying, drais e extrusão no desenvolvimento de nanocompósitos poliméricos
(Universidade Federal de São Carlos, 2014-12-15) Bernardo, Paulo Rodrigo Alves; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537; https://lattes.cnpq.br/6941314463852596
The objective of this work was the development of polymer nanocomposites with montmorillonite organoclays (OMMT) using EVA-OMMT concentrated obtained by spray drying, Drais and extrusion, making the characterization and correlation with the thermal, dynamic mechanical and gas transport properties. LLDPE nanocomposites films were obtained by incorporating the EVA-OMMT powders concentrates. The XRD results showed that the concentrated powders for the spray drying process the shift to smaller angles is more effective for 19% VA and for processing by Drais only 8.5% VA. As for processing by Drais, it was possible to incorporate large amounts of clay, but the results of dispersion and intercalation depends on the use of modified clay and compatible with the matrix used. For processing by spray drying, it showed to be very efficient in incorporation of large amounts of clay in EVA matrix. In the TEM analysis for spray drying powder concentrate, it was observed that, with the increase of MFI of LLDPE matrix and increased of %VA, the areas where the clay is present showed an increase of its dimension and may facilitate the process of intercalation and clay dispersed in the matrix. The permeability results showed a competition between the increased permeability due to a reduction of the crystallinity and, at the same time, reduced permeability due to the higher clay amount in the matrix, since that the clay is properly dispersed. The results showed that the spray drying process is an innovative way to obtain EVA/OMMT concentrated powder with high clay content. The nanocomposite powder with EVA/OMMT 3:1 weight ratio and 7wt% OMMT showed an intercalalated structure and evidence of exfoliation, with 38% oxygen permeability reduction.
Aproximações à história do gênero épico na TV brasileira : um estudo sobre a minissérie A muralha (TV Globo, 2000)
(Universidade Federal de São Carlos, 2014-12-15) Santos Junior, Cid José Machado dos; Paiva, Samuel José Holanda de; https://lattes.cnpq.br/7222933274927263; https://lattes.cnpq.br/3437352764896704
This research presents the investigation of the epic genre´s manifestations within Brazilian audiovisual environment having as object the miniseries A muralha (TV Globo, 2000), based on the novel A muralha (1954) by Dinah Silveira de Queiroz, written by Maria Adelaide Amaral and directed by Denise Saraceni, Carlos Araújo and Luís Henrique Rios. The intersections between the productive practices of TV Globo and the referential legacy of the epic genre in film and television fields are discussed, taking into account aspects of interculturalism and the context of the celebrations of the 500th anniversary of the discovery of Brazil, a period marked by a boom of historic telefictions and the modernization of production strategies and marketing of audiovisual works made by the television network. The work performs an approximation to the binomial TV-cinema relationship in the open television programming and how this articulated the epic genre in his schedule in primetime serial form.
Remoção de etanol por stripping empregando dióxido de carbono
(Universidade Federal de São Carlos, 2014-12-15) Pinto, Camila Ramos da Silva; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/0313948535659038
In the ethanol fermentation processes, the product inhibition phenomenon limits the ethanol concentration in the fermented wine around 10% v.v-1, which results in a large volume of vinasse (around 12Lvinasse/Lethanol) and high level of energy consumption by distillation (around 2,5 Kgvapor/Lethanol). Alternative technologies designed to remove ethanol from the fermentation broth have been studied in the literature. One example is the operation of ethanol entrainment by a carrier gas, known as stripping, which in addition to the removal of the ethanol, a reduction of the temperature of the medium is expected due to the vaporization. In this context, the stripping operation could be used to control the ethanol concentration and cooling the fermentation process, as it could be used after the fermentation to promote the ethanol separation, being an alternative to distillation, reducing the energy consumption. In this study it was analyzed the stripping operation using CO2 (generated during the fermentation) in pilot plant. A factorial design was applied to evaluate the influence of the initial temperature of the solution (T0) and specific flow rate of the carrier gas (CO2) on the following stripping performance parameters: entrainment factor (FA), concentration factor (FC), and temperature reduction factor (FT). Furthermore, a mathematical model was proposed to describe the ethanol mass (mET) and the temperature (T) changes during the stripping operation. It has evaluated the performance of the ethanol recovery system and an extractive fermentation. The results showed that FA and FT were positively affected by T0, because the temperature increasing leads to greater vaporization, promoting greater entrainment of the ethanol and the high extraction of energy from the medium. The FA was also positively influenced by CO2, because it promotes greater mass transfer rate and contact area between the bubbles and liquid phase. The CO2 influenced the FT positively, but only for smaller CO2. Suppose that, for larger CO2, the equilibrium was not reached due the lower residence time of the bubbles in the wine, by removing smaller amount of energy from the liquid phase. The FC was negatively influenced by T0, because of the entrainment of a larger amount of water together with the ethanol has occurred. From the simulated results it was observed that, for smaller CO2, the expected results for the proposed model were close to the experimental, with maximum errors of 10%, concluding that the model is valid, i.e., the equilibrium was reached and the effect of mechanical entrainment was negligible. However, for larger CO2, the errors were higher (20%), concluding that the system has not reached the equilibrium and the effect of mechanical entrainment was significant. The ethanol recovery system of the CO2 stream presented 66.88 and 40.93% efficiency for the assays carried out at 33 and 65ºC, respectively, therefore with a low performance. In the extractive fermentation it was observed that the removal of the ethanol from the medium reduced the product inhibition and increased the substrate consumption rate. The CO2 flowthrough the fermentation medium (CO2 of 1.0 vvm) contributed to the reduction in the temperature of the medium in 41%. Furthermore, there was a decrease in the values of the volumetric flow rates of the cooling water, around 34%, in extractive fermentation when compared to conventional fermentation, indicating a potential savings of the 34% on inputs in the cooling towers and, also, saving energy in pumping this water.
Ferramenta AcheSeuEcoponto: auxiliando a população e o gestor público na destinação adequada dos resíduos sólidos.
(Universidade Federal de São Carlos, 2014-12-15) Melaré, Angelina Vitorino de Souza; Gonzalez, Sahudy Montenegro; https://lattes.cnpq.br/9826346918182685; https://lattes.cnpq.br/5423211915001101; Mancini, Sandro Donnini; http://lattes.cnpq.br/5091149098462301; Carvalho, Tereza Cristina Melo de Brito; http://lattes.cnpq.br/8587567074814594
The population growth combined with the industrial development and the increasing consumption caused several problems related to the solid waste management such as inadequate disposal. Due to global pressures and new polices such as the Solid Waste National Policy, managers need to find solutions to reduce, reuse and recycle waste. The Information and Communication Technologies and the Geographic Information Systems are worldwide used in solutions for waste management. Some of these proposals show that the appropriate disposal increases due to the proximity between the population and the disposal points. This thesis presents a computational tool, called AcheSeuEcoponto, which seeks to assist the population to properly allocate their solid residues. This tool was developed using Geo and Web technologies in a fourth-module architecture. The tool offers to citizens querying the nearest disposal point and disposal points by type of residue . Also, AcheseuEcoponto provides map visualization of the disposal points and directions from a starting point to a disposal point. The social network module allows us to disseminate the tool and as a consequence the disposal points. In addition, the tool provides to managers strategic reports related to poor areas of disposal points, the most popular points and the public profile. As part of this work, we answered questions that measure the scope of the tool, the influence of Web technologies on the dissemination of tool, and the public profile including their knowledge about disposal points. For this purpose, data were collected and analyzed using a questionnaire filled out via the tool, and a Web analytics service. Some results were expected, but the percentage of people who showed lack of knowledge of disposal points was beyond expectation, highlighting the importance of researches within the context of solid waste management.
Indicadores de sustentabilidade em três propriedades de cafeicultura familiar em Araponga MG: uma análise descritiva
(Universidade Federal de São Carlos, 2014-12-15) Souza, Luiza Monteiro; Ferraz, José Maria Gusman; https://lattes.cnpq.br/3851804858390996; https://lattes.cnpq.br/6914832557158394
The present dissertation analyses the production systems and the environmental, economic and sociopolitical sustainability of properties of familybased coffee production with different levels of use of agroecological management in the agroecosystem and in the participation in social organizations in the municipality of Araponga, State of Minas Gerais, Brazil. The present research aimed to evaluate the sustainability of properties of familybased coffee production, and to compare the sustainability of properties in transition to an agroecological management, inserted or not, in the local organizations of the municipality of Araponga. The methodology was performed in four steps: a) selection of the families; b) characterization of the properties by two tools of the Participatory Rural Appraisal, the semi-structured interview and the crossway walk; c) data collection in the coffee crops; and d) Selection of the sustainability indicators for the sociopolitical, economic and environmental dimensions. The research was performed in three families small farmers with coffee production. In total it was selected 62 indicators: 18 sociopolitical, 13 economics, and 23 environmental for the coffee crops; and 8 environmental indicators for the property as a whole. The indicators were measured and translated in a single scale to support de comparison between them. It was established three values of sustainability: 1 critical level; 2 acceptable level; 3 desired level. The results were plotted in a spider chart, in order to facilitate the interpretation of the indicators. The property A obtained better Global Sustainability Index compared with the other assessed properties. In addition, property A showed best indices in the sociopolitical, economic and environmental dimensions of the coffee crops. At the other side, property C was the one with the worst Global Sustainability Index and also the worst indices of the three sustainability dimensions. The property B obtained medium values indices, except for the property s environmental sustainability index, which obtained the best position.
Análise de algoritmos paralelos de ECC em dispositivos móveis multicore
(Universidade Federal de São Carlos, 2014-12-15) Arruda, Tiago Vanderlei de; Sakata, Tiemi Christine; https://lattes.cnpq.br/3560505262283874; https://lattes.cnpq.br/4501453502255478; Barreto, Paulo Sergio Licciardi Messeder; http://lattes.cnpq.br/7732462269737973; Guardia, Hélio Crestana; http://lattes.cnpq.br/1780902767520967
Multicore processors adoption is due to the need of expansion on the computational capacity, what have been done in mobile devices, due to the high availability of online applications in such devices. Elliptic curve cryptography (ECC) can be used in these applications, to ensure the confidentiality in the communication performed by the mobile device. This algorithm has its security on the hardness to solve the elliptic curve discrete logarithm problem (ECDLP), what is harder to solve than RSA s problem, owning equivalent security at the cost of much smaller keys, hence reducing the computational cost of the solutions which implement it. Scalar multiplication is the main and most costly operation in ECC and is composed by the computation of many modular operations. Parallel modular multiplication algorithms where evaluated in this work, which timings were compared with timings of some sequential algorithms. Experiments were performed on a SabreLite IMX6Quad development board, with an architecture similar to a mobile device. On this platform, it was evaluated the transition from the low to the high frequency of CPU, which occurs in ondemand CPU mode during the execution of the algorithms. The relation of proportion among the timings of the algorithms evaluated on performance mode was similar to the powersave CPU mode. Some parallel algorithms were faster than the sequentials in operations among operands with at least 768 bits. Evaluating the behavior of each algorithm when integrated in the computation of scalar multiplication, it was observed that the parallels were faster in operations with a 1536-bit supersingular curve.