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Avaliação da competição entre a espécie nativa Geophagus brasiliensis (Quoy & Gaimard, 1824) e a exótica Oreochromis niloticus (Linnaeus, 1758) confinadas em tanques em diferentes densidades
(Universidade Federal de São Carlos, 2015-06-30) Biagioni, Renata Cassemiro; Petrere Junior, Miguel; https://lattes.cnpq.br/9377772041367252; https://lattes.cnpq.br/6652071008597099
In Brazil, species introduction in freshwater ecosystems has become an important topic in conservation ecology, as it is one of the main causes of biodiversity loss. Invasive species benefiting from the lack of natural enemies outside their original geographic distribution might represent a highly competitive pressure to the native species sharing the same resources of the invaded areas and may lead to changes in the abundance and richness of natural communities. In this sense, for a better understanding of these relationships, it is possible to study experimentally the interactions between invasive and native species evaluating competition effects. So, the objective of this study was to assess, through an experimental approach, if there is intraspecific and interspecific competition between two cichlid fish: a native species, the cará Geophagus brasiliensis and the exotic Nile tilapia Oreochromis niloticus. The objective was to examine if there is differential growth and feeding under different fish densities in consortium or separated. The experiment was conducted in Setor de Aquicultura do Polo Regional Vale do Paraíba - APTA Regional in the municipality of Pindamonhangaba, from March to June 2014. In order to assess the intraspecific competition of each species due to increased density and, comparing them with interspecific competition when the two species coexist in the same tank, five treatments with four replicas were considered. Fish diet studies suggest that there was no intraspecific and interspecific competition for food in this experiment. Despite the morphological similarities between the two fish species, the weight gain is evident and it can be assigned to the treatment itself. Intraspecific competition was not detected, as there was no significant decrease in the average weight gain for both species with increasing density of individuals of the same species. As for the interspecific competition, the results suggest that space availability may have been the main factor of dispute between species, since there was no significant change in diet and the consortium of these species benefited O. niloticus in much higher proportion than G. brasiliensis.
Desafios e oportunidades para a implantação do VLT no Brasil
(Universidade Federal de São Carlos, 2015-06-30) Ribeiro, Euclides Aparecido; Raia Junior, Archimedes Azevedo; https://lattes.cnpq.br/6413793013018019; https://lattes.cnpq.br/1560241440437627
The identification of aspects and circumstance considered as challenges and opportunities inherent in the implementation of the urban transport system operated by the Light Rail Transit - LRT in Brazilian cities are at the heart of the goals of this work. Developed a methodology where theoretical research done through the literature review and the application of Delphi method, used for the query to a group of subject matter experts, formed the basis for completion of the study. The results show its role of facilitator and propellant within the context of urban policies in cities where it already operates on a consolidated basis in several countries, creating expectations that can achieve the same effects in Brazilian cities, which will be deployed and that way, if firm as an efficient urban transport mode, an agent of sustainable urban mobility. It is concluded that, given the reality of urban mobility conditions in most Brazilian cities large and medium-sized, the opportunities for this innovative transport system and holder of proactive features, observed by the methodology applied, are feasible, since , its viability is proven through studies covering aspects such as; the existence of demand, the investment capacity of the governing body, the prospect of financial return and integration with existing modes, to name the most important. Also through the applied methodology, it can be concluded that the challenges for its implementation in the country are of great proportions, starting with the high investments required, through the formulation of policies that integrate the various segments of urban management and culminating with the effective participation of population most interested. Thus, it is understood that the opportunities and challenges for the VLT go hand in hand, on the prowl for decisions that put to the test.
Análise in silico, in vitro e in vivo de compostos organocalcogênios como possíveis anti-inflamatórios
(Universidade Federal de São Carlos, 2015-06-30) Baptistini, Natália; Caracelli, Ignez; https://lattes.cnpq.br/8956527354576143; https://lattes.cnpq.br/8966359690368444
In this work are presented the in silico study of the formation of complexes between organochalcogens compounds with enzymes COX-1 and COX-2 that were carried out in order to study their potential to act as selective inhibitors of COX-2 and thus as anti-inflammatories, as well as the results of in vitro and in vivo experiments of this activity. There were modeled and studied 15 organochalcogens compounds and their enantiomers, with a structure similar to that of the selective drug celecoxib. Compounds 2-(phenylseleno)-2-(2-ethyl-X)acetophenones-4’Y-substituted , with Y = H, Br, CH3, OCH3, NO2 and X = SO2, SO, S, were modeled using as starting point the crystallographic structure of the compound with Y = Br and X = SO. The three dimensional structures of the COX-1 and COX-2 enzymes were obtained from the PDB. The results of the molecular docking calculations were evaluated considering the patterns of orientations/conformations, intermolecular interactions, π interactions and scores. The results of these experiments allowed to propose a mechanism of action as well as a preferred bonding mode that would explain the activity of these compounds as possible inhibitors of COX-2, which is a condition necessary to act as anti-inflammatory. In particular, the compound where Y = OCH3 and X = SO2 (5-OCH3) being selective to COX-2 is the one with the best chances to act as an anti-inflammatory. This is because the OCH3 substituent occupied the S1 subsite of the enzyme, maintaining the interaction with His90 and the SO2 moiety interacts with the Tyr355, an important amino acid for the metabolism of the COX-2 substrate, the arachidonic acid. The other interactions made by the compound, such as π interactions, are important for fixing the ligand in the active site, although they are not directly related to its selectivity. The experiments in vitro and in vivo confirm the in silico results, as the enzyme immunoassay showed that this compound exhibits greater inhibition of COX-2 relative to COX-1. Furthermore, the activity of the 5-OCH3 compound was evaluated with the classical models of edema formation, that is the carrageenan and zymosan induced inflammation in the rat paw, resulting in a significant reduction in paw thickness after two hours and decreasing of the temperature after one hour of the application of the anti-inflammatory agent. As the best results were obtained for the model of paw edema elicited by carrageenan this suggests that the compound acts better in the case of acute inflammation.