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Recuperação de lipase BTL-2 de Bacillus thermocatenulatus produzida em Escherichia coli recombinante empregando suportes magnéticos
(Universidade Federal de São Carlos, 2016-04-06) Lopes, Laiane Antunes; Kopp, Willian; https://lattes.cnpq.br/3856554957880380; Giordano, Raquel de Lima Camargo; https://lattes.cnpq.br/9695542424889786; https://lattes.cnpq.br/6546842202237520
Magnetic supports have gained attention because the magnetic separation is easy, has low cost and high efficiency. Moreover, it allows the purification and immobilization of a biomolecules in single step. Lipases are hydrolases that catalyze the hydrolysis and the synthesis of esters from glycerol and long chain fatty acids. Lipase from Bacillus thermocatenulatus (BTL-2) has interesting properties such as stability at high temperatures (50 °C), alkaline pH (9.0-11.0) and organic solvent (2-propanol, acetone and methanol). In view of the characteristics that makes BTL-2 a promising lipase for industrial application, concentration and purification is of great importance for implementation in industrial scale. In this context, this study aimed to purify and to immobilize BTL-2 lipase from Bacillus thermocatenulatus produced in recombinant Escherichia coli using magnetic silica microparticles (SMMps). Initially, it was determined the best condition for extraction of the enzyme, changing the pH, buffer and ionic strengh during the sonication. Sodium phosphate buffer 100 mM pH 8.0 has shown to be the best condition for the enzyme extraction. The adsorption of lipase on SMMP-octyl was compared with the adsorption performed using agarose-octyl and silica-octyl. The agarose-octyl support showed the best enzyme adsorption yield (RAE), 92.9%, and higher selectivity in the adsorption of the enzyme. The SMMP-octyl showed higher adsorption capacity per volume of support (189.45 UTBU/mL) than silica-octyl. In order to improve the SMMP adsorption performance, it was changed the octyl groups density on the support surface, by activating with theoretical percentages of 25%, 50% and 75% of octyl groups. SMMP-octyl 75%, after activation with 75% of octyl groups, showed to be the best condition, reaching adsorption with RAE of 92.87% (374.33 UTBU/mL), similar to the obtained using agarose-octyl. The commercial macroporous silica (IM S60P) was also used for comparison of activation procedures with different densities of octyl groups (25, 50, 75 and 100%). The results obtained showed higher activity and the adsorbed protein by support volume with SMMp than silica for all activation degrees. Dessorption tests, however, showed to be possible to dessorve all enzyme from the agarose-octyl, but not from SMMp and silica-octil. The presence of negative charges in silica particles, due to possible ionic interaction with the enzyme may be responsible for this result. The concentration of Triton X-100 0.4% was the best concentration to desorb the enzyme of SMMP-octyl 25%, 75% and 100% and concentration of 0.5% (w/v) was the best concentration for desorption in SMMP-octyl 50%. Adsorption tests in the presence of cellular debris were performed and presented similar behavior those ones observed for the centrifuged and dyalized enzyme solutions: the SMMP-octyl 75% showed higher RAE (71.25%) in the presence of cellular debris. Esterification reactions, using the adsorved enzyme on SMMp in different activation degrees as catalysts, showed that the derivative SMMP-octyl 75% allowed reaching 60.93% conversion in butyrate butyl after 24 hours of reaction. The BTL-2 adsorbed derived directly from cell debris in SMMP-octyl were used in recycles and showed satisfactory conversion in the first cycle, however it decreased in the following cycles.
Terra e política : etnografia da luta antibarragem de indígenas e agricultores contra Pequenas Centrais Hidrelétricas da bacia do rio Branco (RO)
(Universidade Federal de São Carlos, 2016-04-06) Furlan, Vinícius Teixeira; Lanna, Marcos Pazzanese Duarte; https://lattes.cnpq.br/8355559441138016; https://lattes.cnpq.br/0571267277128155
The hydroelectric projects in Brazil are marked by an assumption of progress and national development that runs simultaneously with a territorial expansion of areas destinated to many economic activities such as agriculture, livestock and mineral extraction. In many biomes and watersheds we have recent clashes between the expansionist developmental logic with the environmental issues and the traditional peoples. In this context that Small Hydroelectric Power Plants (SHP) from the rio Branco basin (RO), which since 1993 continue multiplying along that river. Because these are smaller projects – dams that generates below than 30MW – they don‘t need a study of environmental impacts and so, the impacted people remain vulnerable to impacts that were not formally predicted. This thesis takes as it‘s starting point the process of bulding these hydroeletrics projects and their impacts on the region‘s population. It aims to describe about the process of clashes and struggle by the indigenous people and small farmers, as well their perspectives to the changes that occured from the construction of the dams. The research took place in diferentes etnographic places: i) reading the legal process in the Ministério Público Federal ii) with the indigenous people, in the Terra Indigena Rio Branco; and iii) with the farmers, most of them, linked to the Movimento dos Pequenos Agricultores (MPA); and in so many other intersections in my path research.
Tempo de espera para a ocorrência de palavras em ensaios de Markov
(Universidade Federal de São Carlos, 2016-04-06) Florencio, Mariele Parteli; Gava, Renato Jacob; https://lattes.cnpq.br/0494315910583969; https://lattes.cnpq.br/0161279835618234
Consider a sequence of independent coin flips where we denote the result of any landing for H, if coming up head, or T, otherwise. Create patterns with H's and T's, for example, HHHHH or HTHTH. How many times do we have to land the same coin until one such two patterns happens? For example, let the sequences being THTHHHHH and TTHTTHTHTH. The number of times that we landed the coin until HHHHH and HTHTH happens it was eight and ten times respectively. We can generalize this idea for a finite number of patterns in any nite set. Then, the rst of all interest of this dissertation is to nd the distribution of the waiting time until a member of a nite colection of patterns is observed in a sequence of Markov chains of letters in from finite set. More speci cally the letters in a nite set are generated by Markov chain until one of the patterns in any fi nite set happens. Besides that, we will find the probability of a pattern happen before of all patterns in the same nite set. Finally we will find the generator function of probability of waiting time.
Autismo : um acontecimento discursivo
(Universidade Federal de São Carlos, 2016-04-06) Telles, Cynara Maria Andrade; Baronas, Roberto Leiser; https://lattes.cnpq.br/4613001301744682; https://lattes.cnpq.br/7040619427859244
In this research, we intend to treat autism in a theoretical, clinical and, also, a discursive perspective. We understand it as a discursive event, considering the progresses since the construction of the disorder category assumed by Child Psychiatry M.D. in the 1940’s, an age when childhood mental disorder and other studies related to childhood, arisen and marked all the subsequent course of this theoretical universe. Our research’s object is the autism’s diagnosis, appointments and re-appointments in science, turning the designation process back to the subject with conductions that contrasts the social balance. Further, we first approach the subject, deliberated as abnormal, and the forms of specifying and positioning him. We will do this course, with the purpose of discussing what has been created until we reach the present historical moment: the nosographic name of autism. Therefore, we will turn back the path that science has followed until the current days, with its classificatory conceptions about autism, always prioritizing the path followed by the theoretical constructions and their effects inside medical, psychoanalytic and philosophical knowledge, as, also, autistic child´s itself. And yet, into the (un)knowledge non-experts person, according to legal supplies and their effects on subjects who experience this condition, whether autistics themselves, whether the people whom they live: parents, brethren, educators, professionals. This course aims to confirming autism as a discursive event, as an example, proposed by Foucault. Our intention with such retrieval, considering the positions occupied by this divergent subject, is to discuss the historical, social and political issues that shaped the scenarios and the places by him occupied.