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Desenvolvimento de métodos para fracionamento de proteínas e metaloproteínas em carne bovina
(Universidade Federal de São Carlos, 2011-09-30) Carapelli, Rodolfo; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045; https://lattes.cnpq.br/1694381993816893
This thesis aimed the fractionation of metalloproteins in beef samples. To this purpose initially it was proposed a method for extraction of proteins using the sample extractor in buffered alkaline medium and surfactant solutions. After optimization were observed approximately 85% extraction efficiency and r.s.d. < 5%, showing the efficiency, reproducibility, simplicity and velocity of the method. After that, the experimental conditions for the fractionation of metalloproteins were evaluated. High performance liquid chromatography (HPLC) and polyacrylamide gel electrophoresis (PAGE) were used for physical-chemical separation and mass spectrometry and optical emission inductively coupled argon plasma (ICP OES and ICP-MS, respectively) as detection methods. The analytes Ca, Cu, Fe, Mg and Zn were evaluated; however, Mg was not detected in any condition of the study. To obtain a condition of appointment of detection for the other four elements, it was chosen to use less energy plasma conditions in ICP-MS (cool plasma), in order to avoid isobaric interference emanating from the plasma when the determination of the elements Ca and Fe. Finally, samples of meat with different maturation stages were analyzed by PAGE and HPLC-ICP-MS. Approximately 17 protein bands could be observed by PAGE and the band of 43 kDa was the more intense. Some peaks were detected for each element by HPLC size exclusion. All items showed at least a fraction above the dead volume of the column, Fe and Zn, and this fraction, also showed a fraction of 17 and 27 kDa respectively.
Controle de estímulos e formação de classes de estímulos equivalentes em crianças e em indivíduos com Síndrome de Down
(Universidade Federal de São Carlos, 2011-09-30) Grisante, Priscila Crespilho; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/5819921002758483
Two studies evaluated emergent stimulus-stimulus relations and selection and rejection controlling relations. Study 1 evaluated controlling relations after two types of conditional discrimination training: standard matching-to-sample (MTS) tasks and tasks using the blank comparison MTS. Participants were five preschool children and two adults and one child with Down syndrome. Two conditions were employed. Condition I involved standard twocomparisons MTS. Condition 2 used mask procedure (or blank comparison procedure) to produce select and reject relations. Both conditions trained AB and BC relations, assessed emergent relations AC and CA and employed new stimulus probes to assess selection and rejection controlling relations in each taught conditional discrimination. Condition 2 also evaluated stimulus class expansion after teaching CD. All participants showed one-node emergent relations. Seven showed class expansion. However, some participants showed positive results for equivalence immediately, others, delayed emergence or yet only after resumption of training with new sets of stimuli. New stimulus probes results showed variability initially, possibly indicating experience with the task as important variable. Novelty control predominated in some cases. Study 2 assessed whether employing new stimulus probes at different stages of the procedure (after conditional discrimination training or after tests for emergent relations) would produce different patterns of responding. Six children were taught two sets of conditional discriminations (BC / AB and EF / ED, in that order). Half of the participants had new stimulus probes after each trained relation for the first stimulus set and after equivalence tests for the second set of stimuli. The other half of participants had this order reversed. Three participants showed equivalence for both sets of stimuli. The stage of new stimulus probes application did not alter the probe results. Taken together, the results of both studies suggest that performance on new stimuli probes is not related to performance on tests for equivalence class formation.
Otimização do processo de mineralização de compostos orgânicos utilizando sistemas eletro-Fenton e fotoeletro Fenton por irradiação UV artificial e solar
(Universidade Federal de São Carlos, 2011-09-30) Almeida, Lucio César de; Bocchi, Nerilso; https://lattes.cnpq.br/5930614700886481; https://lattes.cnpq.br/6233656045399753
Electrochemical advanced oxidation processes based on the Fenton s reaction, such as electro-Fenton (EF) and photoelectro-Fenton (PEF) using artificial and solar UV irradiation were employed in the treatment of effluents containing organic compounds (the textile dye AR 29 acid red 29, the drug paracetamol and the herbicide MCPA 2-methyl-4- chlorophenoxyacetic acid). Furthermore, kinetic studies of degradation of these compounds were performed, using factorial design in order to analyze simultaneously the influence of the parameters current, initial concentration of the catalyst Fe2+ and pH as well as the response surface methodology in order to optimize the experimental conditions. Finally, chromatographic techniques were also used for identification and quantification of the intermediates of the degradation process, among which aromatic compounds, carboxylic acids and inorganic ions. For the three investigated compounds, it was found that the main oxidant was the hydroxyl radical, OH produced by the Fenton s reaction between the catalyst Fe2+ added and the H2O2 electrogenerated by the O2 reduction at the surface of the diffusion air cathode as well as by the photolysis of hydroxylated Fe3+ species. Additionally, the use of the UV radiation, either by artificial or solar source, promoted the fast removal of Fe3+ complexes formed with carboxylic acids which were not actually removed by the OH radical. In the case of AR 29 dye, the highest efficiency was obtained for the PEF process (TOC total organic carbon removal of 95%), followed by EF process; the anodic oxidation presented the lowest performance. For paracetamol and MCPA, investigated only by the PEF process, values of TOC removal of 75 % and 74 % for the optimal conditions at 120 min electrolysis were obtained, respectively. Moreover, MCE mineralization current efficiency values of 71% for paracetamol and 72% for MCPA with EC energy consumption values of 93 kW h kg-1 TOC (7.0 kW h m-3) and 87.7 kW h kg-1 TOC (6.6 kW h m-3) were obtained, respectively. Finally, using distinct liquid chromatography techniques in order to identify and quantify the generated intermediates, plausible mechanisms for degradation of the three investigated compounds up to their complete conversion to CO2 and water were proposed.