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Merleau-Ponty e a crise da razão
(Universidade Federal de São Carlos, 2011-03-28) Marques, Rodrigo Vieira; Simanke, Richard Theisen; https://lattes.cnpq.br/5431145327759147; https://lattes.cnpq.br/3984221131754417
ABSTRACT This work takes its point of departure in Merleau-Ponty s Philosophy, centered in the notion of Crisis of Reason , basing itself on the presupposition that this is a fundamental concept of contemporary phenomenology. In the Cartesian thought, already it was possible to find the idea of the crisis, however, it was the finding of a crisis of sciences . Something similar was also in Valery, especially when he speaks of a crisis of spirit . The novelty of Husserl was exactly in showing that the crisis, as he lived it, was deeper, shook the Reason itself. This work assumes the task of showing that, not limiting to a crisis of sciences, of the spirit or of Reason itself, Merleau-Ponty discusses a present crisis in the man himself, or rather, in the diverse points of view that has about him. In this sense, his philosophical project is based, primarily, on the attempt to establish a dialogue with the points of view of the philosophy and of the science. Therefore, an inquiry of the divergence of these points, is warranted, elucidating not only the scenario in which the conflict is, but also its genesis. Likewise, starting from a Merleau-Pontian understanding of the crisis, finally, this study also assumes the task of asking about the repercussions of this crisis in the relation of philosophical knowledge to itself, then, in the way of his own philosophy to understand its history, being, therefore, the importance of this incursion in the desire to explain what, according to Merleau-Ponty, would be a possible way of overcoming.
Caracterização ambiental da bacia do Alto Jacaré-Guaçu (experimentos laboratoriais e in situ): elaboração de sedimentos sintéticos para avaliação da toxicidade do cádmio
(Universidade Federal de São Carlos, 2011-03-28) Rodrigues, Beatriz Kawamura; Verani, Nelsy Fenerich; https://lattes.cnpq.br/1862746100743391; https://lattes.cnpq.br/7920949423765971
The Alto Jacaré-Guaçu Basin was evaluated regarding limnological and ecotoxicological aspects in four water and sediment sampling campaigns at 14 points distributed in the area. Toxicity tests with water, in the laboratory and in situ, showed chronic toxicity, with effects on the survival, growth and gill morphology of juveniles of both fish species examined (Danio rerio and Poecilia reticulata). The lowest survival percentages in the laboratory assays were observed for point L, and in the field tests for point J1. The analysis of the gills revealed first-stage alterations in the specimens of both species exposed at all the sample points, and there were second-stage alterations (aneurism and vascular congestion) at various points. The high concentrations of nutrients and metals in the basin s water and sediments reveal a system impacted by human activities in the surrounding region. The analyses of metals quantified Cd, Cr, Cu, Mn and Fe levels in the water above those permitted by the Brazilian National Environmental Council (CONAMA 357/05), and of Cd in the sediments above the threshold levels permitted both by national (CONAMA 344/04) and international regulations (CCME, 2003). Simple synthetic sediments were prepared composed of sand, clay and organic matter (obtained from the aquatic macrophyte Scirpus cubensis, at concentrations of 0, 0.25, 0.5 and 1%) to assess the toxicity of Cd. The synthetic sediments were viable for the growth and survival of Ceriodaphnia silvestrii, Chironomus xanthus and Danio rerio, and were suitable for use in spiked experiments. The evaluation of the acute toxicity of the sediments fortified with Cd indicated mean 48-h;EC50 for C. silvestrii of 3.09mg.Kg-1 in the sediments with 0% OM and 2.98mg.Kg-1 in the sediments with 1% OM. The mean 96-h;LC50 for C. xanthus was 18.67 mg.Kg-1 in the sediments with 0% OM and nearly four times lower in those with 1% OM (4.93 mg.Kg-1). A similar pattern was noted for D. rerio, a higher 48-h;LC50 in the sediments with 0% OM (114.88 mg.Kg-1) than in the sediments with 1% OM (75.31 mg.Kg-1). In subsequent experiments, the sediments were also spiked with 0.6mg.Kg-1 of Cd, a concentration considered safe for protection of aquatic life according to the applicable national and international regulations. In these tests, the survival of C. silvestrii was impaired in the Cd spiked sediments, so it was not possible to assess the effects on reproduction. There were also effects on the survival, biomass, mentum morphology and Cd concentration in the tissues of C. xanthus. For D. rerio, the survival and growth were compromised in the sediments with higher percentage of organic matter. Besides this, the organisms showed impaired gill morphology and higher Cd concentration in tissue in function of exposure to sediments spiked with the metal. Based on the results, it can be concluded that C. silvestrii was the most sensitive species to the sediments fortified with Cd, followed by C. xanthus and D. rerio, the least sensitive. These effects on the iv organisms at concentrations considered safe for the biota suggest more conservative thresholds of this metal should be established for tropical aquatic habitats.
Pré-tratamento alcalino (NaOH) do bagaço de cana-de açúcar para a produção de etanol e obtenção de xilooligômeros
(Universidade Federal de São Carlos, 2011-03-28) Nascimento, Viviane Marcos; Giordano, Raquel de Lima Camargo; https://lattes.cnpq.br/8560315748041202
The aim of this study was to optimize the pretreatment of sugarcane bagasse raw and exploded with diluted sulfuric acid, water and sodium hydroxide in order to obtain Xylooligosaccharides in hemicellulose and production of second generation ethanol. The experiments with sugarcane bagasse and exploded with diluted acid and water respectively were performed according to the methodology CCRD (Central Composite Rotatable Design) with two replications at the center point response variables were: amount of xylose (g), acid concentration acetic acid and furfural (g / l) and xyllo-oligomers yield (%). Pretreatment with sodium hydroxide was carried out with sugarcane bagasse according to the methodology of factorial design with two replications at the central point in order to evaluate the influence of time of pretreatment (t), and hydroxide concentration sodium in the release of sugars after hydrolysis. The pretreatment of sugarcane bagasse with fresh H2SO4 concentration 0.8% v / v, 13 minutes at 100 º C allowed 94% extraction of xylan in the form of scyllo-oligomers, with a minimum of xylose, furfural and acetic acid showing as a condition favorable for the extraction of XOS production. The pretreatment of sugarcane bagasse was used only blown hot water already there due to acetic acid, due to the fact that exploded bagasse have already undergone a process of pre-treatment self-hydrolysis at the plant. Provided by washing with water in the ratio 1:5 (w / v) for 5 minutes at 70 ° C allowed the extraction of 80% xylose from bagasse which was already dissolved in the material, this fraction was 62.5% in the form oligomers. If this condition is unfavorable for the production of XOS is great because the production of monomer (xylose), which required a purification step which is very costly. If ethanol is the desired end product is a slight increase in the need of pretreatment conditions for improved xylose production by hydrolysis step by the enzyme xylanase or using acid as catalyst. For the pretreatment of sugarcane bagasse early experiments proved inconclusive for obtaining a correlation between the length, amount of NaOH used in the hydrolysis and fermentation yields. With the experimental design was obtained for 7% NaOH, 30 minutes (min.) 76% of hydrolysis efficiency with a maximum production of glucose 62 g / l and 90% efficiency of fermentation with an average yield of 20g / L ethanol. The materials were characterized chemically and physically before and after the stages of pretreatment showing the openness and better availability of fibers for the enzymatic process.
Estudo cinético da hidrólise enzimática de celulose de bagaço de cana-de-açúcar
(Universidade Federal de São Carlos, 2011-03-28) Carvalho, Mirella Lucas de; Giordano, Raquel de Lima Camargo; https://lattes.cnpq.br/3375214335297840
This work presents a kinetic study of the enzymatic hydrolysis of three cellulosic substrates: filter paper (FP), used as a de-lignified substrate model; sugarcane bagasse (SB) steam exploded; and acid treated SB, the last two treated with 4% NaOH. All SB were chemically characterized. Hydrolysis experiments to study the influence of agitation and substrate concentration were performed in shaker, using Accellerase® 1500, Genencor, at pH 4.8, in 50mM sodium citrate buffer. To verify the substrate concentration effect, cellulose load (weightsubstrate/weighttotal) was 0.5%-13% (for FP) and 0.99%-9.09% (for SB). For FP, the role of the external mass transport resistance was not significant when the agitation speed was in the range 150-300 rpm. It was possible to fit a pseudo-homogeneous Michaelis-Menten model for substrate concentrations up to 13% (w/w). Preliminary tests fitting the model proposed by Chrastil (CHRASTIL J. Enzymic product formation curves with the normal or diffusion limited reaction mechanism and in the presence of substrate receptors, Int. J. Biochem., v. 20, No. 7, p. 683, 1988) indicated that the role of diffusion through the external film was a more relevant feature for steam exploded SB than for FP, at higher concentrations of substrate. It was possible to fit a pseudo-homogeneous model for steam exploded SB, within a range of cellulose concentrations from 0.99% to 3.85% (w/w). Product inhibition had to be considered by the model. For higher loads of steam exploded SB, a modified Michaelis- Menten model, appropriate for heterogeneous systems with high diffusion resistance, was fitted. Finally, for the highly recalcitrant acid treated SB, Chrastil models were fitted. As expected, the complexity of this system regarding to the substrate and to the pool of enzymes acting in synergy, makes difficult the use of one single lumped parameter model for all hydrolysis operation conditions.
Catalisadores à base de Mo, CoMo e NiMo incorporados por impregnação ou in situ em γ-Al2O3, ZrO2 e γ-Al2O3-ZrO2 - avaliação na hidrodessulfurização do tiofeno
(Universidade Federal de São Carlos, 2011-03-28) Baston, Eduardo Prado; Urquieta-González, Ernesto Antonio; https://lattes.cnpq.br/1277176561519941
The preparation of Mo, CoMo or NiMo catalysts supported on -Al2O3, ZrO2 and - Al2O3-ZrO2 was studied. The zirconia contend added into alumina was 20 or 40 % wt.. The supports were synthesized via sol-gel and impregnation or direct addition in the synthesis mixture were used to incorporate the metals. The solids were characterized by thermogravimetric analysis (TG/DTG), X-ray diffraction (XRD), X-ray fluorescence (XRD), Zeta potential, N2 adsorption/desorption, hydrogen temperature programmed reduction (H2- TPR), ultraviolet visible diffuse reflectance spectroscopy (DRS-UVvis), transmission electron microscopy (TEM) and evaluated in the HDS of thiophene used as model molecule. The results showed that the synthesis via sol-gel allowed the formation of the above supports with high specific surface area, with zirconia being highly distributed in the alumina framework. The metal incorporation through impregnation or in situ led to catalysts with Mo, Co or Ni species highly dispersed. The activity data of the thiophene HDS on these catalysts indicated a promoter effect of the incorporation of about 20% of zirconia in the alumina that was simultaneous to the well known Co or Ni promoter character, this evidencing that the Mo activity is affected by the nature of the promoter metal and the textural and physico-chemical properties of the supports, which are strongly involved in the HDS mechanism. The main products of the thiophene HDS were butene-1, n-butane, trans-butene-2 and cis-butene-2, result that corroborates the high selective nature of the Mo based catalysts. Due to the close values of the specific reaction rate of the thiophene HDS on the studied catalysts, it can be concluded that the in situ preparation led to catalysts with very similar properties to those prepared by traditional impregnation. This result is highly attractive from a commercial point of view because it eliminates several steps in the catalysts preparation process, therefore, decreasing the preparation time and costs of labor and energy.
Habilidades sociais de crianças com diferentes necessidades educacionais especiais: comparações múltiplas
(Universidade Federal de São Carlos, 2011-03-28) Freitas, Lucas Cordeiro; Del Prette, Zilda Aparecida Pereira; https://lattes.cnpq.br/8113238388739093; https://lattes.cnpq.br/9607932972038616
Evaluation studies about social skills of children have shown that in general there is an impairment of social skills in learning disabilities, sensory disabilities and other conditions of special educational needs. However, there is a gap in the literature as to a broader comparison of social skills of a greater diversity of populations of children, including sensory disabilities, mental retardation, children with attention deficit hyperactivity disorder, autism, behavior problems, learning disabilities, among others. The paucity of comparative studies to evaluate children with different special needs has hindered the production of empirical knowledge about specific issues to each population. Moreover, the lack of comparative evaluation studies has been an obstacle to the identification of needs that might guide the goals of educational and therapeutic interventions in social skills among children with different developmental characteristics. This study aimed to fill part of this gap and its goals was: (a) to compare, based on teacher evaluation, the repertoire of social skills of children from 12 different groups of special educational needs among themselves and with the normative sample of the Social Skills Rating System- SSRS-BR (Autism, Hearing Impairment, Mild Mental Retard, Moderate Mental Retard, Visual Impairment, Phonological Disorder, Learning Disabilities, Giftedness and Talent, Externalizing Behavior Problems, Internalizing Behavior Problems, Internalizing and Externalizing Behavior Problems and Attention Deficit Hyperactivity Disorder), (b) identify resources and deficits in social skills from each of the 12 groups and (c) assess the degree of prediction of different special educational needs on the repertoire of social skills of the children. Teachers of 120 students in regular and special schools, aged between six and 14 years, from four states, responded to the SSRS-BR to assess the social skills of their students. The results showed that the special needs that had a lower frequency of social skills compared to the other were also the best predictor of deficits in this area, according to the regression analysis performed: ADHD, Autism, Internalizing and Externalizing Behavior Problems and Externalizing Behavior Problems. Furthermore, the groups that most often presented these skills were Gifted and Talented, Children with Visual Impairment and Mild Mental Retard. The comparative analysis identified resources and deficits in specific social skills to each of the 12 participating groups. The results were discussed in relation to the intervention needs of each population, providing possible educational and therapeutic implications.
Modelos estatísticos para LGD : uma visão clássica e bayesiana
(Universidade Federal de São Carlos, 2011-03-28) Varga, Maria Clara Mecatte; Diniz, Carlos Alberto Ribeiro; https://lattes.cnpq.br/3277371897783194
Every day in financial institution is common to nd customers who are unable to honor their commitments. When this occurs we say that the individual is in default. In a possible economic downturn the portfolio could su_er losses due to excessive default clients and high loss rates. At this stage it is essential that financial institutions have a capital reserve to absorb this potential loss. This reserve is known as economic capital. We examined four different models, Normal, Log-Normal, Logit-Normal and Beta Regression, used to determine the individual loss rate, since the client is in default, also known as LGD (Loss Given Default). Such models are used to determine the economic capital. In the models, both the default and LGD depend on a single systematic risk factor, which describes the state of the economy. This means that we considered that the event of default and LGD are correlated. We describe in detail for the four models, two ways of calculating economic capital, using the asymptotic approximation of the distribution of loss rate and the normal approximation. Through a simulation study, we compared the different estimates of economic capital. A bayesian approach to the Beta Regression model is developed modeling mean and dispersion parameter jointly.