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Avaliação do desempenho de meios filtrantes fibrosos na remoção de partículas nanométricas
(Universidade Federal de São Carlos, 2014-03-31) Barros, Priscila Martins de; Aguiar, Mônica Lopes; https://lattes.cnpq.br/0431688649128529; https://lattes.cnpq.br/7778087902508837
Fibrous filters are highly efficient in removing micrometric particles, but when is related on the removal of particles in the nanometer range, their performance is still poorly understood. During filtration, as the particles are deposited on the filter medium, the pressure drops as much as the collection efficiency tends to increase. Thus, this study aimed to determine the deposition of particles in fibrous filter media and their performance, when clean, during this deposition. A cellulose fiber filter (HEPA) and a polyester one were used in the removal of nanometric particles of NaCl. The deposition was assessed by the pressure drop curves as a function of the accumulated mass. The filter performance was avaliated by counting the particles before and after the filter medium and the pressure was monitored to obtain the filtration curves. The filtration rate was maintained at 6 cm.s-1 and the concentration of the generated solution at 0.0042 L min-1 in a commercial inhaler was 5 g L-1. The results showed that the deposition of these particles ocurred first in the interior of the filters media and then in the surface of both filters. The HEPA filter showed lower permeability, higher specific strength of the cake filtration and lower point of clogging. The efficiencies for the cleaned filters ranged from 99.8 to 100% for the HEPA filter and from 15 to 100% for the polyester filter, for the range of particles avaliated. The theoretical efficiencies fitted to the experimental data in the filter of heterogeneous fibers. For the filter of homogeneous fibers, the data also did fit satisfactorily. Both filters showed, problably in the transition region between the mechanisms of collection, a randomness of experimental data. During deposition, the efficiency of the filter medium increased with the deposition of particles, reaching 100% of efficiency at the end of filtration.
Corpos reverberantes: novas (re)configurações de fitness e wellness nas academias de ginástica
(Universidade Federal de São Carlos, 2014-03-31) Rossi, Vanberto José; Leite Júnior, Jorge; https://lattes.cnpq.br/7253561448346772; https://lattes.cnpq.br/8029019783495881
This monograph of completion of the course focuses on the social construction of the body in the environment of the gym. The proposal in general terms, is studying it in their everyday social profiles, delineate aspects of its components and establish some relationships between the gym, the subject and society, seeking to understand these relationships, especially with respect to the amount of this establishment to the current historical moment. The gym configures itself as a "no place", a social and a individual link between the parties and all that there is a large confluence of factors in that environment. On the other hand, there are still some traditional characteristics that perpetuate through the gym. Thus, there is the subject that it uses for the cult of the body, moved or not by social imperatives, and also the one who need it to survive, either through clinical or financial imperatives. These types of subject originate social niches that mediate an exchange of interest result of a universe that hovers between the imperatives of social and individual needs.
Interpretar o enunciado ou dialogar com a enunciação? uma análise sobre processos de leitura no ENEM
(Universidade Federal de São Carlos, 2014-03-31) Branchini, Camila Sabatin; Brito, Maria Isabel de Moura; https://lattes.cnpq.br/8640312408255752
This paper discusses the reading concepts that are present on the Enem items, specifically on the tests of Languages, Codes and Their Technologies (LCT), in editions from 2009 to 2013. For this, we adopted as the main theoretical reference of this research the notion of discursive genders, (BAKHTIN, 2010; 2011; MARCUSCHI, 2005) the concept of enuciate and enunciation (BAKHTIN, 2010; BRAIT, 2012; FLOWERS, 2009; GERALDI, 1993) as a basis to substantiate the reading conceptions (BAKHTIN, 2010; GERALDI, 2010; KLEIMAN, 1989; 2006; MARCUSCHI, 2005; Matrix Reference Enem, 2009; FREIRE, 1997; ROJO, 2004.) To support the goals of the Enem test as an instrument of government review, we did a recap of the structure and objectives of the Enem evaluation, through the notion of competence and skill as part of a historical, social, political and economic context that enter politics public in education and become part of the official discourse of the documents (LDB, PCN, PCNE). Contextualization that makes clear how changed the way of evaluate. Others researches has hunched on this content, it points to the relevance of the chosen corpus. Launch a new look, new readings on the corpus, shows the need for ever more clearly the social importance of Enem forming a new way to evaluate We have chosen, for that, two items of each year, starting in 2009, when the advent of the New Enem, to 2013, last evaluation. This choice had as criterions issues related to mother language which utilizes the genders as basis for discussion on the enounced of the questions in the test. From a theoretical-methodological assumptions, regarding the form of analysis developed within the humanities, allowed us to analyze the corpus by the perspective of sociological method and/or Bakhtin's discourses and Ginzburg qualitative method (the paradigm called evidentiary). Were made hipoteses about the interpretive walk performed by the candidates at the time they read the enounced of the objective questions proposed on Enem test. From the analyzed editions, we adopted as corpus 10 items of the LCT test which works issues related to mother language. Then, we trace an overview of the types of reads that the candidate/reader made over five years of evaluation, considering that it depends of some elements, such as how they prepared the enounced of the item, the enunciative context, previous knowledge of the candidate. We conclude that the evaluative profile of ENEM tends to approach the reading under the bias of linguistic structure, grammaticalized, often part of the theme, and a few times, considers the enunciation, the dialogue, the interaction, ie, the discursive bias.
Estudos metabólicos, enzimáticos e genéticos do fungo endofítico Penicillium brasilianum
(Universidade Federal de São Carlos, 2014-03-31) Fill, Taícia Pacheco; Rodrigues Filho, Edson; https://lattes.cnpq.br/3667941735597178; https://lattes.cnpq.br/0741638379707154
The project "Metabolic, enzymatic and genetic studies of the endophytic fungus P. brasilianum" resulted in biosynthetic studies of bisphenylpropanoid amides, the brasilimides, confirming the origin of these substances via phenylpropanoid biosynthesis pathway, very unusual in fungi. PAL activity, the first enzyme involved in this biosynthetic route was successfully evaluated and the conditions of PAL production by P. brasilianum were optimized (culture medium and induction of PAL adding Phe to the culture), and the incubation conditions of the enzymatic reaction. The specificity of the PAL enzyme was studied, and the enzyme showed activity toward all substrates tested, including acting as TAL (tyrosine ammonia lyase). In vivo studies throught the addition of different substrates lead to N-acetylation confirmed by spectroscopy data. The genome of the fungus P. brasilianum was sequenced, and extensive studies through bioinformatics lead to the gene encoding PAL enzyme. From molecular biology studies, the enzyme was cloned and expressed as recombinant PAL fused to a SUMO protein and a his-tag at the N- terminus of the protein in pETSUMO vector expressed in E. coli BL21 (DE3) to obtain the best conditions for enzyme overexpression in its soluble form. The purification process of the recombinant enzyme was studied from a single purification step (affinity chromatography) by pH gradient elution, obtaining a high degree of purity confirmed by one-dimensional electrophoresis. The pure recombinant PAL enzyme obtained was characterized by MS and biochemically yielding Km values of 4,8 mM. Recent studies seem to point out that there is a relationship between the production of brasiliamides when the fungus is subjected to stress conditions. The PAL enzyme appears to be involved in defense mechanisms in this fungus, as has been described for plants.
Estudo da oxidação preferencial do CO por catalisadores a base de irídio
(Universidade Federal de São Carlos, 2014-03-31) Silva Júnior, Waldir da; Bueno, José Maria Corrêa; https://lattes.cnpq.br/0157452280626031; https://lattes.cnpq.br/0950063786043919
Ir/Al2O3 samples were prepared to evaluate the influence of the particle size of the metal in the preferential oxidation of CO reaction. Initially, samples with different amounts of iridium were prepared in an attempt to get different particle sizes. Samples containing 1, 2, 6 and 10 % Ir/Al2O3 were prepared. The samples were prepared via dry impregnation, from alcoholic solutions of the salt precursor and calcined at a temperature of 400 °C. The -Al2O3 support was calcined at 550 °C. The catalytic tests were carried out using a flow rate of 100 ml/min of a mixture containing 1% O2, 1% CO, 45% H2 and balance in He. The results of XRD of these samples showed no characteristic peaks of iridium and the metal dispersions were very similar, raising the possibility that even with the increased loading of iridium samples showed no significant differences in their structure. After realize catalytic tests using the same density of active sites, it was found that the structure of the samples was very similar and the different results of activity and selectivity were due to the different densities of active sites. In order to obtain samples with different structural properties, was fixed in 4% the iridium concentration on the catalysts and was varied the calcination temperature of the catalysts (400, 550 and 750 °C) and the support (550 and 750 °C) and was studied the influence of calcination temperature of the catalyst as well the support. Results of XRD and hydrogen chemisorption showed large differences in particle size and metal dispersion. The total flow of the catalytic tests was reduced to 50 mL/min, maintaining the concentrations of the gases. DRIFTS spectra confirmed the structural differences due to the increase of calcination temperature of catalysts, showing a large decrease in the interaction between CO/metal. The results of the catalytic tests showed that by increasing the calcination temperature of the catalysts there is a loss of activity but these catalysts were more selective. A strong influence of the calcination temperature of the supports in the activity and selectivity of the catalysts was also observed. The results show that the PROX reaction is very sensitive to catalyst structure.
Desenvolvimento e caracterização de nanocompósitos de blendas de PA6/AES compatibilizadas com copolímero acrílico
(Universidade Federal de São Carlos, 2014-03-31) Oliveira, Amanda Dantas de; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537; https://lattes.cnpq.br/0010723066123700
Toughened polyamide 6 (PA6) nanocomposites were obtained by incorporation of acrylonitrile-EPDM-styrene (AES). As compatibilizing agents was used the copolymer methyl methacrylate-anhydride (MMA-MA). The effect of the blending protocol of the components and of the addition of three montmorillonites (Cloisite®30B, Cloisite®20A and Cloisite®Na+) was investigated. The nanocomposites were prepared in a twin screw extruder and then its microstructure, lamellar structure, mechanical, thermal and rheological properties were characterized. The morphology and properties of the nanocomposites were significantly affected by different nanoclays and blending protocol. The characterizations by transmission electron microscopy (TEM), small angle X-ray scattering (SAXS) and wide angle X-ray difraction (WAXD) indicated intercalated structures for the nanocomposites with Cloisite®20A and Cloisite®Na+, in contrast to the ones prepared with Cloisite®30B that exhibited exfoliated structure. The addition of nanoclays in the blends increased the modulus for all nanocomposites with respect to the pure blend. Excellent impact strength results were obtained for the nanocomposites compatibilized with MMA-MA with respect to the blend PA6/AES and ternary systems ternary (PA6/AES/clay), demonstrating the effective presence of the copolymer as a compatibilizer of these systems. It was observed a good correlation between mechanical properties and morphology. An increase in rigidity is accompanied by a corresponding increase in toughness when the clay is present in both phases. A significant increase in long period of nanocomposites compared to the PA6 was observed through SAXS results. In this work, polymer blends compatibilized with MMA-MA were also prepared and a significant increases in the mechanical behavior these materials was observed.
Catalisadores à base de CuO, Fe2O3 ou CuO-Fe2O3 suportados sobre y-Al2O3, ZrO2 ou ZrO2/y-Al2O3 para a redução de NO com CO
(Universidade Federal de São Carlos, 2014-03-31) Pires Neto, Nilson do Espírito Santo; Urquieta-González, Ernesto Antonio; https://lattes.cnpq.br/9012578333707579; http://lattes.cnpq.br/2389975677904655
NO, NO2 and N2O nitrogen oxides, named NOx, strongly contribute to the air pollution and to minimize their emissions are used catalytic processes. The catalytic reduction of NO with CO has the advantage to simultaneously abate both pollutants. For that reaction are used noble metal based catalysts, but due to their scarcity and high cost, many research have been established to their substitution by transition metal oxides, which have high potential to catalyze that reaction. Those new catalysts beside to be active to the NO reduction with CO, they must be highly selective to N2 formation, stable at high temperatures and especially resistant to the presence of the interfering compounds (O2, SO2 and H2O). In this work were prepared Fe2O3, CuO or Fe2O3-CuO catalysts supported on y-Al2O3, ZrO2 or ZrO2/y-Al2O3. The supports were prepared via synthesis sol-gel using metallics alkoxides as precursors and the active phases introduced by impregnation of Fe(III) or Cu(II) nitrates. The obtained solids were characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption measurements, hydrogen temperature programmed reduction (H2-TPR) and their activity evaluated by the reduction of NO with CO between 100 to 600°C in the presence or absence of SO2, O2 and H2O. The synthesis via sol-gel resulted in y-Al2O3 and ZrO2/y-Al2O3 supports with high specific surface area that allowed adequately distribute the CuO and Fe2O3 oxides, which did not present X ray diffraction peaks. The catalysts were considerably active in the reduction of NO with CO, with the bimetallic ones being slightly more selective to N2 formation. In the presence of SO2, the Fe2O3/y- Al2O3 and Fe2O3/ZrO2/y-Al2O3 catalysts showed more catalytic stability. The presence of O2 led to a significantly NO conversion loss due to the direct CO oxidation by O2. In the presence of H2O or of all the interfering compounds, the NO conversion loss was more pronounced, except the CuO/ZrO2, that was more resistant in the presence of H2O.
Etnografando o riso: reflexões antropológicas sobre um programa televisivo de humor
(Universidade Federal de São Carlos, 2014-03-31) Carlos, Daniel Pícaro; Lanna, Marcos Pazzanese Duarte; https://lattes.cnpq.br/8355559441138016; https://lattes.cnpq.br/0943450154094305
The work presented here was originally proposed as an ethnography of the production of television entertainment. As a first issue, it aspired to understand the way the TV is thought by those who produce it daily. Electing to field the backstage of A Praça é Nossa, the oldest of the Brazilian comedy TV still on display, the search ends up embarking on other reflections, in which the realized ethnography is used to support the structural analysis of comedic sketches presented by the program.
Avaliação da produção de ciclodextrina glicosiltransferase (CGTase) por fermentação submersa de Paenibacillus sp
(Universidade Federal de São Carlos, 2014-03-31) Prado, Cleiton Dias do; Tardioli, Paulo Waldir; https://lattes.cnpq.br/7312478474540871
Cyclodextrins (CDs) are cyclic oligosaccharides that show the ability to encapsulate a large number of organic molecules at the molecular level. Thus, they have large application in pharmaceutical, food, and cosmetics industries. CDs may have different sizes; however the most common are formed by 6, 7, and 8 glucose units, called α, β and γ-CD, respectively. These compounds are produced from starch by hydrolysis catalyzed by cyclodextrin glycosyltransferase ( CGTase - EC 2.4.1.19 ) enzyme. CGTase is commonly produced from bacteria of the genus Bacillus and Klebsiella pneumoniae. Due to the commercial importance of this enzyme and of the microorganisms producing CGTase whose enzyme is capable to produce only one CD, this work aimed to evaluate the CGTase production by the bacterium Paenibacillus sp. F37. The experiments aimed to assess the potential for enzyme production by Paenibacillus sp. F37 strain and also the characterization and classification of the enzyme. Analysis of enzymatic activity was accomplished by cyclization activity of the supernatant of the culture medium, which was monitored by the production rate of β-CD at 50°C, pH 8.0 using a solution of dextrin as substrate. Initially it was evaluated the effect of the pH (6.0 to 10.0) over the microorganism growth into solid Horikoshi medium without starch. It was observed that the microorganism grew better at pH 8.0, being this pH adopted for assays using liquid Horikoshi medium without starch. In this step it was established the following conditions to the bacterium growth: 10h, 37oC, and agitation of 120 rpm in an incubator. The CGTase production step was performed into Horikoshi medium containing 1% (m/v) soluble starch (enzyme inducer), and pH and production time were evaluated. Under standard conditions (37oC, 120 rpm, 16h, and culture medium prepared in 0.1 M tris-HCl buffer pH 9.0) the volumetric activity from the culture medium achieved about 800 U/L, corresponding to a productivity of 50 U/L.h-1. The characterization of the crude enzyme showed that the CGTase from Paenibacillus sp. F37 strain has maximum cyclization activity around 50oC and pH 6.0. Under these conditions the enzyme showed to have a half-life time around 2 h. At the growth conditions (37oC, pH 9.0), the enzyme show to have a half-life time around 3h, being almost inactivated around 5h. Thus, the enzyme production in a medium where pH starts at 9.0 and is decreased to around 6.0 during the growth showed to be a good strategy to prevent denaturation of the enzyme. The CD production into batch reactor and their characterization by colorimetric and chromatographic methods allowed classifying the enzyme as a β-CGTase (ratio α-:β-:γ-CD of 0:1:0.26). At the CD-production conditions (50oC, pH 8.0, 50 g/L of dextrin, 1.6 U/g of dextrin, and 92 h) it was achieved β-CD productivity around 100 mg/L.h. These results showed that Paenibacillus sp. F37 strain is a promising microorganism for producing CGTase.
Estudo químico de Bowdichia virgilioides (Fabaceae) na busca de inibidores seletivos de cisteíno peptidases
(Universidade Federal de São Carlos, 2014-03-31) Silva, Taynara Lopes; Vieira, Paulo Cezar; https://lattes.cnpq.br/8923844563320377; https://lattes.cnpq.br/9412487106628965
This work describes the isolation of bioactive secondary metabolites of the plant species Bowdichia virgilioides in the search for selective inhibitors of cathepsins K, L and V. Cathepsins are enzymes that have as primary function the degradation of proteins in the lysosomes, and are also related to development of diseases such as osteoporosis, rheumatoid arthritis, atherosclerosis and various cancers. This dissertation describes the bioactivity-guided study of the ethanol extracts and fractions obtained from the stems and leaves of B. virgilioides through fluorimetric inhibition assay of the enzymes studied. The extracts of B. virgilioides were subjected to successive fractionations using different chromatographic techniques leading to several pure substances. The isolated substances had their structures elucidated by NMR uni- and bi-dimensional and mass spectrometry. The hexane and ethyl acetate fractions of stem afforded eleven substances: 2 triterpenes, lupeol and lupenona; the mixture of steroids β-sitosterol and stigmasterol; 1 ester derivative of trans pcoumaric acid; 1 furofuran lignan, syringaresinol; 1Benzofuran derivative, bowdenol; 1 coumestrol derivative, 8-methoxycoumestrol, and 3 isoflavones, 7,3'-dihydroxy-4'- methoxyisoflavone, 5,4'-dihydroxy-7'-methoxyisoflavone and 4-hydroxy-7-methoxyisoflavone. All compounds were tested on their ability to inhibit the enzymes at a concentration of 100μM. 8-Methoxycoumestrol showed inhibition superior to 70% for cathepsin V. The potency of this inhibitor was determined and the IC50 value was found to be 17.4 ± 1.0μM for cathepsin V. The ester derivative of trans p-coumaric acid also showed good inhibition above 70% for cathepsin L and V at a concentration of 50μg/mL. So, a series of 8 esters derived from p-hydroxybenzoic acid, p-coumaric acid, cinnamic and ferulic were prepared, and have been evaluated regarding their inhibitory activities of the cathepsins at a concentration of 100μM. n-Octyl pcoumarate ester showed the best percentage inhibition for the three enzymes. The constituents of the hexane fraction of leaves of B. virgilioides were analyzed using the techniques 1H NMR and GC-MS.