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Geometria, modelagem e código de barras na construção de luminárias
(Universidade Federal de São Carlos, 2013-03-21) Fernandes, Estela Aparecida; Soares, Márcio de Jesus; https://lattes.cnpq.br/3273672989988386
The presented work aims to allow students to infer about the different concepts by building Mathematicians luminaire. For this, occur following the development of a didactic, teaching methodology that consists in presenting the project to the students who undergo an initial production or initial assessment - production of texts, conversations, problems - from which different activities are performed, worked in modules on the topics. It is then rated the performance obtained through the production end. This methodology was applied to two classes of 2nd year of high school in a public school. The first step began with a presentation of the sequence followed by initial production, which allowed students to exhibit their knowledge of mathematics involved in the production end (luminaire). The proposal focuses on various topics from basic mathematics possible, through different methodologies, the resumption of constant content addressed thus enabling advances in the teachinglearning process. The topics taken up are observed in the plane geometry, which underlies the study of Space Geometry. The practice of mathematical modeling is used to rescue the concept of function with real meaning to students. The news was on account of the discovery of mathematics Barcode. And finally, the closing of the work took place with the presentation of the final production performed by students.
Influência da linhagem da levedura e das condições de cultivo no processo de isomerização e fermentação simultâneas da xilose
(Universidade Federal de São Carlos, 2013-03-21) Moraes, Guilherme Silveira; Zangirolami, Teresa Cristina; https://lattes.cnpq.br/4546701843297248; https://lattes.cnpq.br/9013240485281830
The conversion of the hemicellulosic fraction in ethanol is a factor that impacts on the economic viability of the second generation ethanol production process from sugar cane bagasse. Hemicellulose from bagasse is a heteropolymer constituted by pentoses and glucose, being xylose the predominant sugar (~ 21 %). Among the available technological alternatives for ethanol production from xylose, SIF process (Simultaneous Isomerization and Fermentation), consisting of xylose conversion to xylulose by glucose isomerase (GI) enzyme and xylulose fermentation by the yeast S. cerevisiae, is considered a promising alternative. The main objectives of the present work were: i) evaluate the performance of different S. cerevisiae strains towards xylulose intake and ethanol productivity; ii) assess the influence of cultivation conditions (temperature, oxygen availability and initial xylose concentration) upon ethanol and xylitol production by the selected strains; iii) define the operation conditions for the continuous SIF process, using a system of fixed bed reactors associated in series. Preliminary experiments were conducted in 50 mL flasks, containing 4 g of pellets with a load of 20 % of immobilized GI, co-immobilized with yeast (load of 10 %) in alginate gel. For the screening of yeasts showing better performance on ethanol production from xylose, two commercial baker´s yeast strains (Itaiquara® e Fleischmann®), three industrial strains (BG-1, CAT-1 e PE-2) and one lab strain (CEN.PK113-7D) were evaluated. These experiments were performed at 35 oC, using a medium composed by xylose (60 g/L), urea (5 g/L), CaCl2 (1.9g/L) and several salts, at initial pH of 5.6. Additional SIF studies were carried out with the selected yeasts Itaiquara®, BG-1 or CEN.PK113-7D under different temperature conditions (40 oC), aeration (15 mL flasks) and initial xylose concentration (130 g/L) for comparison with the results obtained at the standard conditions. For SIF cultures, samples were withdrawal and the concentrations of reducing sugars were determined by DNS method while xylose, xylulose, ethanol and by-products (xylitol, glycerol etc) concentrations were assessed by liquid chromatography. Cell viability was also measured at the beginning and end of the experiment. When comparing the different yeasts, Itaiquara® strain presented the best performance, reaching ethanol concentrations of 22.4 g/L, with a productivity of 2.1 g/Lh. The conversion of xylose was similar for all studied industrial strains as well as among the baker s yeast and lab strains. Concerning the group of additional experiments, at 40 oC, a decrease of viability and ethanol selectivity was observed for Itaiquara®, whereas productivity and selectivity for CEN.PK113-7D. was improved. For the studies conducted under semianaerobic conditions, the yeast BG-1 showed an increase in selectivity and yield. However, the reaction time increased to app. 45 hours. On the other hand, the performance of strain Itaiquara® was not altered by the lower level of oxygen tested. In the experiment with 120 g/L of xylose, more than 40 g/L of ethanol was obtained in 24 hours of cultivation. Thus, we conclude that the SIF process proposed in the present work is a viable alternative for the production of ethanol from xylose or lignocellulosic residues. For the operation of the continuous system composed by fixed bed reactors associated in series, the recommended conditions include the Itaiquara® yeast with a temperature no higher than 35 oC, keeping the total residence time around 10 hours for a feeding supply containing 60 g/L of xylose.
Recobrimento de sementes silvestres em panela rotatória
(Universidade Federal de São Carlos, 2013-03-21) Rosso, Giovana Américo; Sartori, Dermeval José Mazzini; https://lattes.cnpq.br/3207012091734322
In order to minimize the effects caused by the development of Brazil, such as the suppression of riparian forest, one has searched for tree species that have the characteristics needed for the recovery of degraded areas. Given this, studies focus on higher plants of encapsulated wild fruits, especially the Mabea fistulifera Mart. Considering that M. fistulifera reproduces through embryonic units that need to be treated, this study aimed to evaluate the drying of wild fruits with explosive dehiscence and the coating "in natura" seed with gel mixture via coating pan, as well as evaluating the tolerance of embryos related to the immediate effects of the processes. Thus, the experimental procedure consisted of the collection of capsular fruits and extraction of seeds of fruit by drying so were analyzed drying methods via radiation, natural convection, forced convection and coating pan. It was considered for the drying methods analysis the opening fruit speed and seed vigor. Thus, all processes allowed physiological recovery of embryos, but the extraction method via pan promoted the highest opening speed of the fruits. Once performed the extraction, the seeds were separated from the inert material obtaining pure batches of seeds. There were also characterizations of size, shape and specific mass obtaining the results (0,78±0,05) cm, (0,67±0,04) cm and (0,59±0,04) cm for Dmax, Dmédio and Dmim, respectively, form factor (0,75±0,01), specific mass of (1,20±0,01) g/cm³ and apparent mass of (0,82±0,01) g/cm³. Analyzes were also made for chemical seed yielding (82,93±0,11)% of dry matter (19,03±0,78)% crude protein, (1,18±0,11) g/kg calcium (0,65±0,03) g/kg magnesium (0,58±0,04) g/kg phosphorus (13,45±0,33) g/kg potassium (0,70±0,03) g/kg of sulfur. The process of coating seeds, through reaction between sodium alginate gel and calcium chloride salt at different angles of inclination and rotation speed of the coating pan, was also analyzed. Thus, it was found that to achieve the coating of the particles it was necessary to prepare the particle surface by chemical scarification, in order to increase the surface roughness of the seed, followed by rehydration with saturated calcium chloride. This way, it was found that the angle of 25° and speed of 25 rpm generate the greatest quantity of mass adhered on seeds. In addition, tests were performed to verify the efficiency of the coating process, and with the lowest angle set in experimental design was found higher values of efficiency. In tests of particle growth was evaluated that the process time was approximately 8 seconds. Finally, the analysis and processing of data obtained through statistical techniques and equations from literature were performed. In this way, the results contributed to improvements in drying processes of wild fruits and the coating of seeds of the pioneer species M. fistulífera.
Desenvolvimento de eletrodos de carbono vítreo modificados com nanotubos de carbono para a determinação de analitos de interesse farmacêutico
(Universidade Federal de São Carlos, 2013-03-21) Oliveira, Geiser Gabriel de; Fatibello Filho, Orlando; https://lattes.cnpq.br/9859737944357808; https://lattes.cnpq.br/6504190570083114
In this work, the development of electroanalytical methods for the determination of methotrexate (MTX), propylthiouracil (PTU), propanolol (PROP) and verapamil (VPM) in pharmaceutical formulations is described. In these methods it was employed a glassy carbon electrode (GC) modified with dihexadecyl hydrogenphosphate (DHP) or polyallylamine hydrochloride (PAH) film containing immobilized multi-walled carbon nanotubes (MWCNTs). Initially, the electrochemical behavior of each modified electrode was studied by cyclic voltammetry at different scan rates for a 1.0 × 103 mol L1 potassium hexacyanoferrate (III) in 0.1 mol L1 potassium chloride solution. Applying the Randles-Sevcik equation, it was observed an increase of the active area of MWCNTs-DHP/GC and MWCNTs-PAH/GC electrodes of 1.5 and 3.1 times respectively in comparision with the GC electrode. The square wave voltammetry, differential pulse voltammetry and linear sweep voltammetry parameters were studied and optimized for each analyte and then it was selected the best technique for the development of the analytical method. In the developed method for MTX determination in pharmaceutical formulations, it was used the GC electrode modified with MWCNTs and DHP (MWCNTs-DHP/GC), employing differential pulse adsorptive anodic stripping voltammetry (DPAdASV) technique after the optimization of experimental conditions. The analytical curve obtained was linear in the MTX concentration range from 5.0 × 10-8 to 5.0 × 10-6 mol L-1, with a limit of detection (LOD) of 1.2 × 10-8. The MTX was quantified in commercial samples and the results compared with an HPLC method, and the relative errors ranged from -4.0 to 4.0%. An analytical method for determination of PTU in pharmaceutical formulations was also developed using a modified GC electrode with MWCNTs within a PAH film (MWCNTs-PAH/GC) and linear sweep adsorptive cathodic stripping voltammetry (LSAdCSV). After the optimization of experimental conditions, the analytical curve was linear in the PTU concentration range from 5.0 × 10-6 to 5.8 × 10-5 mol L-1, with a LOD equal to 1.0 × 10-6 mol L-1. The PTU was quantified in commercial samples and the results were compared with those results obtained using the British Pharmacopoeia method. The relative errors obtained were between -1.0 and 2.0%. Using DPAdASV technique and a MWCNTs-PAH/GC electrode, PROP was determined in pharmaceutical formulations. The analytical curve was linear in the concentrations range from 7.5 × 10-8 to 1.0 × 10-6 mol L-1 PROP, with LOD equal to 6.3 × 10-8 mol L-1 and the results were in close agreement whit those obtained using the Brazilian Pharmacopoeia method at a confidence level of 95 %. The relative standard deviation ranged from 2.5 and 1.2%. Finally, as a fourth electroanalytical method, a square wave adsorptive anodic stripping voltammetry (SWAdASV) was proposed for determination of VPM in pharmaceutical formulations using a MWCNTs-PAH/GC electrode. The analytical curve was linear over the VPM concentration range 5.0 × 10-9 - 1.0 × 10-7 mol L-1, with an LOD of 3.6 × 10-9 mol L-1 . The VPM was quantified in pharmaceutical samples and the results compared with results obtained using the method of the Brazilian Pharmacopoeia.
O estado enquanto acionista : a atuação da BNDESPAR no capitalismo brasileiro contemporâneo
(Universidade Federal de São Carlos, 2013-03-21) Desiderio, Wellington Afonso; Grün, Roberto; https://lattes.cnpq.br/6028266827740491
In the last two decades there has been a lot of changes in organizational dynamics in Brazil, because the principles of financial capitalism went into effect on the national economy. The starting point of these changes were the mergers and acquisitions that occurred in the 1990s. Through these ones, international companies came to Brazil and brought with them financial principles that dominated the international economy. Among these principles, the Corporate Governance and Industry Venture Capital (venture capital and private equity) are outstanding. In this new Brazilian scenario an actor of extreme relevance is the State; it acts directly on financial markets through BNDESPAR, which is a subsidiary of the National Development Bank (BNDES). This action occurs through industry venture capital (venture capital and private equity), and its goal is to promote the development of domestic enterprises. The empirical data of this study indicate that BNDESPAR can act in Brazilian companies through venture capital industry due to corporate governance, this tool enables the monitoring of BNDES subsidiary in corporations which it owns. Thus, the Corporate Governance being a tool that attends to the interests of the State, it is disseminated via BNDESPAR in Brazilian companies. For BNDESPAR, promoting the company in the segment of venture capital involves raising it to go public on the stock exchange. On the other hand, through the private equity segment, it involves establishing the main indices of corporate governance in the investee companies. It also verified the performance of the actors responsible by BNDESPAR. The data indicate that these actors have primarily political experience and expertise in finance. We analyzed also the actors who occupied the positions of elite at BNDES in the last 10 years, it was mainly realized that these actors, in fact, after they have passed through the state bank, they are founded private equity funds or they are acting as CEO on boards of companies.
Relações entre ambiente, traços, composição e funcionamento de comunidades vegetais de cerrado
(Universidade Federal de São Carlos, 2013-03-21) Carvalho, Gustavo Henrique de; Batalha, Marco Antônio Portugal Luttembarck; https://lattes.cnpq.br/3893228815181339; https://lattes.cnpq.br/0896575446907453
Identifying the relative importance of deterministic and stochastic factors to the assembly of local communities has been tagged as one of the fundamental questions ecologists need to answer. Niche-based theories predict that the subset of species from the regional pool that occur in a local community presents a trait distribution that has been shaped by biotic and abiotic factors. The neutral theory, on the other hand, predicts that the species that compose the regional pool are functionally equivalent. Local communities formed from stochastic processes would, thus, present abundances not significantly different from those in the species pool. We collected traits on all woody individuals in 100 25m2 quadrats to test if we could predict local abundances using a pool of species and traits. We combined plots into large scale, intermediate scale, and fine scale samples. We used random sampling, spatial distance, soil characteristics, and fire to assemble species in different scales and environmental gradients. In the Brazilian cerrado, fire and nutrient-poor soils are likely promoters of habitat filtering. To test if traits improved the predictions generated by the information present in the pool, we used maximum entropy models coupled with permutation tests. We could accurately predict local abundances of the 73 species in the pool. Dispersal limitation was the main factor assembling communities at all the scales we studied, but the effects of stochasticity became more important as the scale became local. Traits explained little of the uncertainty present in local abundances, but coupled with pool frequencies they yielded large coefficients of determination.
Avaliação experimental da fragmentação do hábitat em comunidades de macroinvertebrados associados a macroalgas
(Universidade Federal de São Carlos, 2013-03-21) Daunt, Ana Beatriz Pierri; Tanaka, Marcel Okamoto; https://lattes.cnpq.br/2768658925977757; https://lattes.cnpq.br/8306035178191448
Habitat fragmentation is a major cause of biodiversity loss, so understanding the effects of habitat fragmentation on the structure and dynamics of natural communities is very important to biodiversity conservation. This study evaluated whether habitat fragmentation affects the structure of macroinvertebrate communities associated with macroalgae in the sublittoral of a protected shore in the northern coast of São Paulo State. First, we carried out an experiment to evaluate the colonization of the aquatic fauna to substrates with different structural characteristics after two and four weeks for colonization (Chapter II). Our results showed that the tubular plastic net exposed to four weeks of colonization would be efficient to the execution of the fragmentation experiment (Chapter III). Then, we built artificial landscapes that formed large patches, which were later fragmented to analyse the development of communities relative to position within the patches (edge vs. interior) and resulting patch size . Higher taxon richness and gastropod abundance were recorded in the patch edge, but no significant differences were found among patch sizes. We found a significant effect of fragmentation, with lower abundances of Gammaridea (the dominant taxon), Ophyuroidea and Pycnogonida after the experimental fragmentation. Edge environments may shelter higher richness and abundance of organisms due to higher inputs of food and organism settlement. The lack of experimental studies in this systems makes it difficult to determine the appropriate spatial scale to study and to interpret patch size differences. Our results support the importance to preserve seaweed beds for the conservation of macroinvertebrate diversity, independently of patch sizes. Thus, these results can help to understand the effects of habitat fragmentation in marine systems, supporting management actions for biodiversity conservation.
Utilização de mensagens criptografadas no ensino de matrizes
(Universidade Federal de São Carlos, 2013-03-21) Oliveira, Reinaldo Donizete de; Soares, Márcio de Jesus; https://lattes.cnpq.br/3273672989988386
The present work aims at showing the development and implementation of a Didactic Engineering on the use of encrypted messages in teaching matrices to students who are attending the second high school year at Esmeralda Soares Ferraz School in the City of Ourinhos-SP. This work begins with a question related to the discouragement and apathy of students in studying mathematics and suggests, taking the teaching of matrices through encrypted messages by transposition of letters, a different approach from those commonly applied, through which, the student eager to solve them, will get engaged and interested in learning, in a simple way, the concepts of matrices and transposed matrices, being protagonist of his/her search for knowledge.
Produção de ácido glucônico e xarope de frutose a partir de sacarose catalisada por enzimas em reator airlift
(Universidade Federal de São Carlos, 2013-03-21) Mafra, Agnes Cristina Oliveira; Tardioli, Paulo Waldir; https://lattes.cnpq.br/6868423702339380
The sugarcane sugar (sucrose) is a raw material produced in abundance in Brazil, being attractive to produce high added-value by-products. The gluconic acid (GA) can be obtained by multienzymatic conversion of sucrose, using three enzymes. Invertase, responsible for the inversion of sucrose to glucose and fructose, glucose oxidase (GOD) responsible for the glucose oxidation and catalase (CAT) responsible for decomposition of hydrogen peroxide. In multienzymatic process fructose is obtained as a byproduct, also of great interest to the food, pharmaceutical and chemical industries. In this study, the production of GA from sucrose in airlift reactor is evaluated. Temperature and pH of maximum activity were determined for the enzymes invertase, GOD and CAT , as well as the thermal stability in the absence of substrate. Invertase enzymatic activity was quantified by formation of reducing sugars on a 200 mM sucrose solution at 30 ° C, and pH 4.8. The enzymatic activity of GOD and the CAT were determined by monitoring respectively the formation of H2O2 from a solution of glucose 1 g/L, 25°C, pH 5.0 and the decomposition of H2O2 from a solution of H2O2 35 mM, 25°C, pH 7.5. Invertase showed maximum activity at 45 ºC and pH 5.0; GOD at 55ºC and pH 6.0 and CAT at 25 ° C and pH 8.0, respectively. From the activity profiles as a function of temperature and pH, the operational conditions of 50, 45 and 40°C at pH 5.0 and 6.0 were pre-selected for the multienzymatic process. It was found that the best half-lives times of the soluble enzymes, invertase, GOD and CAT, occurred in the condition of 40°C and pH 6.0, respectively 137, 105 and 98 h. A kinetic study was carried out at 40°C and pH 6.0. The kinetics of the enzyme invertase showed a behavior best predicted by the model of substrate inhibition. Michaelis-Menten model (MM) was fitted to experimental data of GOD and substrate inhibition model best predicted the kinetics behavior of CAT. The proposed kinetic models were used to estimate enzyme/substrate ratio (w/w) used in the production of GA in agitated and aerated and airlift bioreactors. On the other hand, in the batch assays conducted in airlift bioreactor were obtained AG real yields of 80.38 ± 5.69% and global yields of 103.20 ± 13.96% and conversion of sucrose of 98.86 ± 0.97%; obtained after 5 h. A new set of kinetic parameters including volumetric oxygen transfer coefficient (kLa) was based on the experimental data from tests in airlift bioreactor. These showed that Bi-Bi Ping-Pong model both with or without product inhibition correspond satisfactorily to the tendency of the experimental data.
O ensino de probabilidade com o uso do problema do jogo dos discos
(Universidade Federal de São Carlos, 2013-03-21) Lima, Felipe Mascagna Bittencourt; Paterlini, Roberto Ribeiro; https://lattes.cnpq.br/6240750958932738; https://lattes.cnpq.br/3446336830903679
In this work, we present a didactic proposal which aim is to introduce Probability to students of Basic Education. This proposal consists in a sequence of classes that is based on the Game of Discs Problem, which goal is to determine the diameter that a disk must have so that when launched randomly on square tiles, has a certain probability of intercept their separating lines. This problem was put to students from three classes of third year of a state high school in a contextualized form and before introduction of Probability by the teacher. The idea was that the students should try to solve the problem in groups and with a minimal help from the teacher. Even with students having difficulties, it proved possible, and they solved the problem using a concrete experimentation of the game. For this, they approximated the probability of winning with a certain disc to the win percentage in the experimentation and, through graphical modeling, they achieved the desired answer. The motivation to this teaching propose was the observation by the author that the way that Probability has been traditionally teached has proven ineffective. Moreover, it can be saw that several Brazilian official documents, such as the National Curriculum Parameters (PCN) and Curricular Proposal of the State of São Paulo, as well as other researchers, suggest that concrete experimentation should be performed for a effective teaching of Probability. With the results obtained, presented in this dissertation, we conclude that our didactic proposal is efficient, bringing motivating classes and providing an environment in which students, besides learning Probability, could exercise their creative capacity.
Análise estatística do modelo de Nelson e Siegel
(Universidade Federal de São Carlos, 2013-03-21) Brocco, Marcelo Bertini; Diniz, Marcio Alves; https://lattes.cnpq.br/8948404469003829
The present paper studies the yield curve, an important tool for financial decisions, due to its fundamental role in the implementation and evaluation of monetary policies by the central banks. It also shows market perspectives in relation to the future development of interest rates, inflation and economical activities. Using an adequate model and a reasoned assessment of its parameters enables us to adjust the curve as far as possible to the real curve and hence obtain most precise and trustful results. These results were acquired by studying a model which was developed in 1987 by Nelson and Siegel and used to draw up the yield curve. Considering the model s limitations, diferent methods were used to attain the estimated parameters, such as Ordinary Least Squares, Maximum Likelihood and Bayesian Inference in the static version. The Nelson-Siegel model is widely used in Brazil and in the rest of the world, due to its economical idea, easy implementation and eficient adjustment into diferent formats that the yield curve is able to deal with. By considering the restrictions of the model, we found estimations for the parameters of the model safer than other and besides, the main point of this work is an estimation form of parameters of time together with others parameters of the model without considering one fixed value for it.