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Continuidades e rupturas no processo de trabalho dos marmoristas : 1890 1950 e os dias de hoje.
(Universidade Federal de São Carlos, 2006-08-28) Moroni Filho, Elio; Truzzi, Oswaldo Mário Serra; https://lattes.cnpq.br/5005536921435787; https://lattes.cnpq.br/9730375282476186
This work describes the similarities and differences in the work process of treating ornamental stones, comparing this against two periods of time (1890-1950 and the present time), the technological stages and work organization in marble and granite companies of the past and of the present. Data collection was based on various research sources and qualitative techniques (systematic direct observation and oral statements) and quantitative research (survey interviews). It was verified that the local marble and granite companies - since the end of the XIX century up until the present time - are installed in the mercantile establishments that operate in the third main stage of the productive cycle of the ornamental stones, elaborating final products from unrefined or polished slabs that are supplied by third parties. The semi-craft work organization and arduous work conditions seem to be conditioned to the technology employed by these companies. Along the XX century, local companies underwent technological improvements and upgrading, using new equipment and tools that increased efficiency of the final treating process. However, such technological changes did little to significantly improve work conditions and to eliminate predominant manual work with mechanical tools; although the work has been disassociated with partial craft work, the worker s skills remains the basis of the work process. However, the local companies have been incapable of modernizing their work units, not upgrading their systems with relation to available technologies worldwide. Mechanization and automation of the process, already incorporated by many companies in this sector, could modify the profile of the variables afore mentioned. Nevertheless, the small local companies are incapable of substituting or upgrading their equipments due to their low capitalization level at the rate the market develops and presents equipment.
Perda de matéria orgânica dissolvida por células flutuantes de cianobactérias potencialmente tóxicas expostas a altas intensidades de luz
(Universidade Federal de São Carlos, 2006-08-28) Santos, Roseli Machado dos; Vieira, Armando Augusto Henriques; https://lattes.cnpq.br/4428377384377272; https://lattes.cnpq.br/9339465247386683
Anabaena spiroides and Microcystis aeruginosa are cyanobacteria that frequently bloom in Barra Bonita Reservoir. These floating organisms and the characteristic turbulence found at the reservoir exposure the cells to higher light intensities by lifting them from lower depths in the photic column to surface. The sudden exposure at higher irradiance could cause photoinhibition and photooxidation. This phenomenon could liberate high amounts of dissolved organic matter. This work aimed to investigate the carbon fixation photoinhibition in cells of A. spiroides and M. aeruginosa exposed to high irradiances, the chlorophyll photooxidation and the DOM released by cells of cultures differing in their physiologic state, after exposure to high irradiances through time at laboratory and field investigations. A. spiroides suffered photoinhibition and liberation of dissolved organic matter when exposed to irradiances higher than their EK during four hours as well as when exposed to irradiance of 2000 µmol.m-2.s-1 for eight hours. M. aeruginosa did not present photoinhibition in any case, however, their C14OD liberation was significantly increased. The higher indexes of C14OD excreted by theses cyanobacteria are not apparently due to cell damage. Hence it might represent an adaptation factor to higher irradiances. Similar results were found in experiments incubated in Barra Bonita reservoir.