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Juntos mais desiguais: um desejo de "nação" paulista não-realizado
(Universidade Federal de São Carlos, 2011-09-21) Magri, Mailce; Escudeiro, Richard Miskolci; https://lattes.cnpq.br/1623888309974862; https://lattes.cnpq.br/2069929216797979
Assuming that every nation is an imagined community concept created by Benedict Anderson in his book Imagined Communities I propose a discussion about the existence of different projects for the construction of a Brazilian nation, paying special attention to a "Sao Paulo state project". As guideline, I use the subaltern studies, which question the hegemonic centers' theoretical colonialism and the modernity dominant conceptions. This dissertation is based on the subaltern studies literature and on the selection of texts from the period chosen for this study: the years between 1870-1922. These analyses intend to show the existence of a "Sao Paulo project" for the nation, which demonstrates a "admiration" for the North- American racial segregation. This "admiration" was a common theme in many papers written after such project failed.
Desempenho de meios filtrantes na filtração de gases a altas pressões
(Universidade Federal de São Carlos, 2011-09-21) Tanabe, Eduardo Hiromitsu; Coury, José Renato; https://lattes.cnpq.br/9778700143605069
The presence of residue in the transport of natural gas in pipelines may result in numerous losses for the gas companies, such as obstruction of measuring equipment, decrease in product quality, and reduction in the lifetime of equipment. A very efficient and inexpensive way for removal of particles is the use of gas filtration. Despite the wide applicability of filters, there are very few studies on natural gas filtration, due to their operating conditions, because they work at high pressures. Thus, research in this area is extremely important to obtain more information about this subject. Therefore, this study aimed to examine the behavior of different filter media used in gas filtration at high pressures. The particulate matter used was the phosphate concentrate and the filter media were polyester, polypropylene, cellulose and metal. The absolute pressure of the system varied from 93 kPa to 693 kPa and the volumetric flow from 14 l/min to 74 l/min in the permeability trials and the fluid used was compressed air. The system pressures of 193, 393 and 693 kPa were used in the filtration trials and the superficial gas velocity was kept constant at 0.05 m/s. The results showed that the permeability constants, k1 and k2, did not present significant variations with the increase in the system pressure, that is, the values tended to a constant value. Simulations to determine pressure drop using natural gas as fluid were performed considering that the permeability constants did not present large variations. The results indicated that the increase in system pressure resulted in greater filtering capacities for a given pressure drop. It was observed that the highest absolute pressure applied to the system (693 kPa) provided the lowest pressure drop at the filter for the same powder mass collected in the filtration trials. An analysis of the dust cakes porosity revealed that the increase in pressure resulted in more porous cakes which were less resistant to gas flow. Also, it was verified that the increase in the system pressure provided an increase in the fractional efficiency of the filters for particles smaller than 5 μm.
Produção, isolamento e identificação de metabólito com atividade citotóxica de cultura de Streptomyces carpaticus
(Universidade Federal de São Carlos, 2011-09-21) Ferreira, Douglas; Badino Júnior, Alberto Colli; https://lattes.cnpq.br/6716019534474825
This study addresses the production, isolation and identification of the substance present in culture broth of Streptomyces carpaticus which showed high biological activity against human tumor cell lines HL-60 (promyelocytic leukemia), MDA-MB 435 (breast carcinoma ), HCT-8 (colon carcinoma), SF-295 (glioblastoma). Cultures of Streptomyces carpaticus in culture medium DSMZ 65 were performed in shake flasks. Initial bioassays of the culture broth extracts showed antiproliferative activity close to 100% inhibition against the tumor cell lines. In order to obtain greater volume of culture medium to isolate the compound of interest, bioreactor cultivations were performed in bioreactor with 12 L working volume. After microfiltration and ultrafiltration of the culture broth through a 0.22- micron and 3 kDa membrane filter, the retentate was then subjected to partitioning using different organic solvents (ethyl acetate and n-buthanol). The fractionation of the extracts was bioguided based on the bioassay results and on HPLC-DAD-MS analysis. The fractionations led to the isolation and identification of the cyclodepsipeptide Valinomycin as responsible for cytotoxic activity. In addition, the results showed the strain as isopalmitic acid producer. Values of inhibition concentration (IC50) obtained for the compound isolated from the broth, against various tumor cell lines, presented low values ranging between 2 and 10 ng.mL-1. The use of bench scale bioreactor, bioguided fractionation and mass spectrometry proved to be fundamental to the development of this study, because it was evidenced that the discovered compound responsible for the antiproliferative activity is produced at very low concentrations. The use of HPLC-DADMS/ MS by selective ion monitoring was able to propose a methodology to estimate Valinomycin production in four different culture media tested, an important result for future studies regarding the development of the production and purification process of Valinomycin by S. carpaticus.