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Experiências agroecológicas de comercialização no Rio Grande do Sul: Associação dos Agricultores Ecologistas de Ipê e Antonio Prado (AECIA) e Centro de Apoio ao Pequeno Agricultor (CAPA)
(Universidade Federal de São Carlos, 2012-02-10) Nascimento, Fábio Schwab do; Beskow, Paulo Roberto; https://lattes.cnpq.br/5370208348544496; https://lattes.cnpq.br/6322985841208222
This dissertation has as an objective to present the results of the research conducted for the Master Course of Agroecology and Rural Development of the Federal University of São Carlos. This study aimed to analyze the different existing processes of commercialization in the Rio Grande Do Sul in relation to the concept of organization of its producers and the forms of commercialization used. To develop the present work, a case study will be used, having as object two experiences in the Rio Grande Do Sul. The chosen experiences was the Association Ecologists Farmers Ipê and Antonio Prado (Ipê and Antonio Prado/RS) and the Center of Support Small Farmers (Santa Cruz do Sul/RS). It was conducted a socioeconomic analysis of these experiences, observing how its forms of organization and commercialization influences in the reached results.
Estruturação das assembléias de aves que utilizam diferentes fisionomias de cerrado na Estação Ecológica de Itirapina, São Paulo
(Universidade Federal de São Carlos, 2012-02-10) Fieker, Carolline Zatta; Dias Filho, Manoel Martins; https://lattes.cnpq.br/1346547036069954; https://lattes.cnpq.br/4453761595730340
Interações tróficas entre a espécie Geophagus brasiliensis e a comunidade de macroinvertebrados bentônicos em reservatórios de diferentes graus de trofia
(Universidade Federal de São Carlos, 2012-02-10) Nunes, Marcos Vinicius; Verani, José Roberto; https://lattes.cnpq.br/0053232138684810; https://lattes.cnpq.br/2486673216326112
The studies related to the interactions among populations in the aquatic communities are essential for providing relevant information for the understanding of energy and matter pathways in the ecosystems and subsidize to the formulation of trophic web models.The occurrence of flexible diets is a marked feature of many species in the ichthyofauna of Tropical Rivers, where the same species can alternate the exploitation among food items according to the changes in the relative availability of food resources induced by temporal spatial and or ontogenetic changes. In this context, this study aimed to analyze the trophic interactions existing between the species Geophagus brasiliensis (Quoy & Gaimard, 1824) (Osteichthyes, Cichlidae), and benthic macroinvertebrate community in three reservoirs (Monjolinho Reservoir, Fazzari Reservoir, Broa Reservoir) in order to know its feeding mode, whether there is food selectivity or preference and which would be the most suitable trophic category for the species. Benthic macroinvertebrate communities in sediments sampled simultaneously to G. brasiliensis population were analysed and experiments were carried out in order to know the feeding mode of the species. Biometric measurements for ecomorphological analyses and analysis of stomach contents of the fishes were performed and based on qualitative and quantitative analyses of the macroinvertebrates consumed and their availability in the environment the values for the selectivity index of Paloheimo were calculated for the reservoirs sampled. The results showed that benthic macroinvertebrates are often used as food resource by the populations of G. brasiliensis with great participation in its diet, allowing us to characterize this species as a benthivore. Also, it was observed that G. brasiliensis has food preference for Chironomidae larvae.
Comportamento mecânico da liga Ti-6Al-4V com superfície modificada por laser de femtosegundo para uso biomédico
(Universidade Federal de São Carlos, 2012-02-10) Santos, Alan dos; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://lattes.cnpq.br/6009157017178581
Stainless steel orthopedic implants are still the most widely used in Brazil due to their lower cost. There is, however, a tendency to expand the use of special alloys such as titanium-based, due to clinical advantages that they present, notably the low modulus of elasticity and the best biocompatibility among the metallic biomaterials. The surface treatments aim to develop substrates suitable for bone growth, thus preventing the implantation of the prosthesis with PMMA cement, which results in an efficient mechanical fixing, but there is no biological interaction between implant and bone. There are several surface modification techniques, all of them improving at some level the process of osseointegration. However, researches have focused on biological aspects of the process and, despite the durability of the implant, there is currently no objective information in the literature about the influence of surface treatments on the mechanical behavior under cyclic stresses. The laser surface modification emerges as a promising alternative, since it permits precise control of parameters, regular surface development, induces reduced mechanical and thermal damage, and is known to promote osseointegration. The femtosecond laser, in particular, allows pulses of short duration (10-15s), reducing even more the damage caused by heat input. This study evaluated the influence of surface modification by femtosecond LASER in the fatigue resistance of Ti-6Al-4V alloy samples. S-N curves were determined for the reference samples and for the samples with modified surface. The topography developed and the fracture surfaces were analyzed by scanning electron microscopy. The femtosecond LASER has developed a regular surface with a bimodal distribution of microcolumns and ripples, and did not cause severe damage adjacent to the modified surface, however, has significantly reduced fatigue resistance.
O ondansetron, antagonista dos receptores 5-HT3, reverte o efeito ansiolítico das injeções de midazolam no hipocampo ventral de camundongos expostos aos modelos labirinto em cruz elevado (LCE) e exposição ao rato
(Universidade Federal de São Carlos, 2012-02-10) Fachini, Gabriel; Souza, Azair Liane Matos do Canto de; https://lattes.cnpq.br/2352004564367849; https://lattes.cnpq.br/6803191985946603
Animal models have often been used to investigate the neurobiology of emotional states (fear and anxiety). In this sense, the elevated plus maze (EPM) and the rat exposure test are effective to evaluate these states and EPM exposure (aversive stimulus) can result in activation of serotonergic pathways with projections to structures belonging to the defense system, such as , amygdala, septum, hypothalamus, periaqueductal gray (PAG) and hippocampus. The hippocampus has a large amount of serotonin receptors (5- HT) and gamma-aminobutyric acid (GABA). In the present study, we used male mice of Swiss Albino, received surgical implantation of guide cannula and subsequent administration of drugs in the ventral hippocampus. After recovery, the animals were tested in EPM (Experiment 1 and 2) or the test exposure to the rat (Experiment 3 and 4). In Experiment 1, administration of midazolam (3.0 and 30.0 nmol) produced anxiolytic effect characterized by increased percentages of entries and time spent in the open arms of the EPM reduction measures and ethological (risk assessment) as percentages of dives stretched and secured. In Experiment 2, mice received combined injections Saline + Saline, Saline + MDZ, ondansetron (OND) + Saline and MDZ (30.0 nmol) + OND (0.03 nmol, antagonist of 5-HT3). Combined treatment of Sal + MDZ produced anxiolytic effect and this effect was reversed by the combined administration of OND + MDZ. The porcentanges of entries and time spent in open arms were lower (P> 0.05) than those found in group Sal + MDZ. Experiment 3 showed the effects of exposure of mice in the presence of mouse toy (RB = neutral stimulus) or mouse real (VR = aversive stimulus, Long Evans rats), under the administration of midazolam (3.0 14 and 30.0nmol). The animals were exposed to RV shortening the holding box (model effect) compared to animals exposed to RB. Animals treated with MDZ in two doses, there was an increase in transitions between the sides of the apparatus, increased time in the area of operation and increases the latency of escape to the protected area and contact time with the grid. In Experiment 4, we evaluated the effect of combined injection of midazolam and ondansetron protocol (Experiment 2). The MDZ 30.0 nmol produced anxiolytic effects and the blockade of this effect when the mice were combined administration of ondansetron and midazolam in the ventral hippocampus. Data from this study suggest that, first, control over emotional reactions and defense of the ventral hippocampus of mice exposed to EPM test or exposure to the rat are mediated via GABABenzodiazepines. Furthermore, there is a likely cross-modulation between GABAergic interneurons and 5-HT3, for blocking 5-HT3 via ondansetron can decrease the GABA release.
Estudo de reações sólido/líquido e sólido/gás em altas temperaturas: o caso das reações do PbSO4EPbO no processo pirometalúrgico de reciclagem de Pb a partir de baterias chumbo-ácido
(Universidade Federal de São Carlos, 2012-02-10) Santin, Betânia de Oliveira; D'Alkaine, Carlos Ventura; https://lattes.cnpq.br/8699821828310072; https://lattes.cnpq.br/0036756630569466
This report presents a study on there reactions and transformations occurring at high temperatures with the two main constituents of scrap lead-acid batteries (Pb/H2SO4) oxide and lead sulphate (PbSO4 and PbO). It was conducted through simulations of possible reactions occurring in a pyrometallurgical process for reprocessing these devices discarded where, besides the battery scrap, different percentages of coking coal (C), iron chip and sodium carbonate (Na2CO3). As the literature pointed PbO as a product of many intermediate reactions in the production of secondary or recycled Pb, it was given the same importance to PbSO4, which is the main component of scrap batteries Pb/ H2SO4. For the implementation of this thesis, a mini pilot plant was designed and constructed with good temperature control of this metallurgical process. Using this tool a study of variation of them ass of the compounds treated thermally separated and in mixtures, was performed in a temperature range of 100 oC to 1000 oC. In general, the compounds and thermally treated mixtures were characterized via Absorption Spectroscopy Infrared and Raman Spectroscopy. Spectroscopic data were analysed by comparions with standard spectra of pure substances or, in the case of the mixtures, of these components already treated thermally separated. Contrary to what has been described in the literature, it has been found experimentally that PbO is not reduced by simply reducing the atmosphere generated by adding C in the oven, but by a combination of this with the reducing atmosphere generated by the flame used for heating the Scrap loads with all the other added reagents. Even under the conditions applied in this study, contrary to the hither to described in the literature, Fe chips did not act reducing the PbSO4. However, in the presence of C, the reduction temperature of this sulphate to PbO decreased considerably. When Na2CO3 was added to the mixturePbSO4 + C this decomposition temperature further