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Licitações e editais de empreendimentos públicos de construção e sua influência no processo de projeto
(Universidade Federal de São Carlos, 2011-08-11) Zanferdini, André Saretta; Novaes, Celso Carlos; https://lattes.cnpq.br/7340467051481570
The delay in the conclusion of the public construction projects, that are frequently paralyzed, as well as the foreseen cost rise, may highlight the existence of recurrent technical, financial, political, administrative or judicial problems, which were originated even before hiring a firm. Therefore, this paper aims to analyze how the bidding and engineering work contracts refereeing legislation, within the Powers of Union, of States and Municipal district, contributes so that the solutions taken from designs do not get fully attended during the process of public construction ventures. Such a purpose, which initially required additional knowledge on public construction projects and design process, which was achieved with the execution of the literature review and the case studies, that in turn involved three public contracting companies and three contracted firms, as a way to get different perceptions of the same process. The evidence obtained from the contract bidding analysis, properly validated with answers from series of questions applied to contracting party and contracted, along with the literature review provided the conclusion of this work, as well as the creation of a proposal that aims to reduce the problems related to the accomplishment of the solutions taken from designs of public construction projects.
Caracterização trófica da ictiofauna da Represa do Beija-Flor, na Estação Ecológica de Jataí, Luiz Antônio, SP
(Universidade Federal de São Carlos, 2011-08-11) Oliveira, Elisa Martins de; Peret, Alberto Carvalho; https://lattes.cnpq.br/0995579236780271; https://lattes.cnpq.br/3345072251027342
The feeding habits, reproduction and growth of omnivores, herbivores, detritivores and iliófagos fish species from the Beija-flor reservoir in Jataí Ecological Station were investigated. This provides information on the trophic interaction between species, feeding habits, establishing guilds and also provides subsidies for monitoring the the Beija-flor reservoir. Emphasis was placed on Prochilodus lineatus, presented as a larger sample in this study, so the reproduction and growth of only this species was analyzed. Eleven samplings were made between September 2008 and October 2009. The diet was assessed through the food importance index. Three species showed an herbivorous diet (Leporinus striatus, Schizodon nasutus and Metynnis sp.), two species were omnivorous with a tendency to insectivory (Astyanax altiparanae and Astyanax fasciatus), two species were omnivorous with tendency to herbivory (Leporinus aff. friderici and Geophagus brasiliensis), one species was ilyophagous (Cyphocarax modestus) and one species was detritivore (Prochilodus lineatus). The reproduction of Prochilodus lineatus occurred between November and February and their allometric growth was negative. The richness of organic matter in the sediment of the Beija-flor reservoir is evidenced in the high proportion of organic matter found in the C. modestus and P. lineatus stomach contents. Detritus was a food source of higher quality for these species so this reservoir provides an important place of feeding. There is no seasonal pattern of feeding overlap between species, that was caused by significant amounts of feeding overlap occurred in the both seasons. The analysis of dietary overlaps showed that food partitioning was higher within detritivores. Although there was overlap between many the species, there is no competition between them because the niche was shared. The Beija-flor reservoir is an environment where the detritivore food chain has an important role in the system because the reservoir is an ecosystem of decomposition.
Ensaios bioquímicos e celulares para a identificação de novos inibidores de TcGAPDH seletivos à HsGAPDH
(Universidade Federal de São Carlos, 2011-08-11) Soares, Fabyana Aparecida; Montanari, Carlos Alberto; https://lattes.cnpq.br/9200533791228786; https://lattes.cnpq.br/7008669907649678
Chagas disease is a tropical neglected illness; nearly 10 million people are infected, in 2008 it was responsible for the deaths of about 10 thousand people. At present, only two medicines (benznidazol and nifurtimox) are available to treat this disease and they lack of efficacy/safety in chronic phase. This scenario is changing due to advances in the search for new trypanocidal agents. The glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme of Trypanosoma cruzi appears as a suitable target for drug discovery. In the present work, a kinetic study using Isothermal Titration Calorimetry (ITC) were carried out to investigate the activity of eight NAD+ analogs against GAPDH. ITC was been used to measure the heat exchange during reactions making it a powerful tool of identification of bioactive compounds. Study compounds showed inhibitory activity on TcGAPDH enzyme and its homologous human GAPDH. The apparent inhibition constant values (Ki app) were in the range from 15,98 to 91,25 M describing competitive inhibition mechanisms. Important steps in medicinal chemistry maybe biochemical followed by cell-based assays were, for instance, Saccharomyces cerevisiae could be used as a model to assess the cytotoxic activity of compounds. The technique used to study the action of chemical compounds in yeast was the fluorescence spectroscopy. Five out of eight compounds showed no activity against S. cerevisiae. This is a good indication that study compounds have low cytotoxicity, which makes them candidates for in vitro studies on the parasite.
Estudo da corrosão de aço AISI 1020 em meio de petróleo
(Universidade Federal de São Carlos, 2011-08-11) Rios, Emerson da Costa; Souza, Ernesto Chaves Pereira de; https://lattes.cnpq.br/1505400360366643; https://lattes.cnpq.br/8791195940411823
The chemical attack on crude oil, which contains corrosive compounds such as H2S, CO2, naphthenic acids and salts dissolved in the aqueous phase, combined with effects of varying pH, temperature, flow and pressure, has great influence on the corrosion rate in equipment steel. Given the small number of papers in the literature relating to the study of corrosion of steel in contact with crude oil, and the importance of the topic, this study aimed to characterize the main corrosion of steel AISI 1020, which has similar chemical composition most of the steel pipelines in oil. Due to the high resistivity of oil, this study used the techniques of Electrochemical Impedance Spectroscopy, EIS, and Electrochemical Noise, EN, for the measurements of steel corrosion. Initially tests were carried out mass loss in steel samples immersed in simulated oil with different amounts of acetic acid in order to define the concentrations and their corrosive effects. Considering the oil contained in the aqueous phase were studied by EIS types of steel corrosion in oil OAPI 17 with different amounts of sea water emulsified. The spectra obtained by EIS showed three semi-circles, and at high frequencies (> 10Hz), the predominant effect of the capacitive and resistive bulk oil and in medium (10 - 0.05 Hz) and low (<0.05 Hz) frequencies the effects of adsorption, electrical double layer and charge transfer resistance at the interface of the electrode is predominant. Optical images were obtained after the accelerated corrosion of steel/emulsions systems and for polarization curve measurements in situ of the steel/water extract, where there was variation in the morphology of the attack with the variation in the amount of water emulsified in oil. Considering the presence of corrosive three species: sea water (0.5 and 4.0%), naphthenic acid (500 and 3,000 ppm) and H2S (50 ppm and 1,000), and using a 23 factorial design of experiments to obtain the effect cross these species, the corrosion process was investigated using the technique of EN in the open circuit potential, EOC. Analysis of current noise signals was done with the help of wavelet transform which gave rise to the power distribution diagrams. These diagrams show that there is a greater tendency to pitting corrosion in environments where the concentration of H2S the amount of water are higher, which means that for the greater amount of naphthenic acid corrosion in general the contribution was relatively higher. The results observed through the power distribution diagrams were confirmed by morphological analysis of the samples corroded. The methods used in this work allowed to estimate the speed and identify the predominant type of corrosion of steel in oil containing aggressive chemical species that are commonly found in Brazilian petroleum.