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Conhecendo fractal no ensino médio: árvore pitagórica
(Universidade Federal de São Carlos, 2013-08-26) Nicola, Celso Henrique; Soares, Márcio de Jesus; https://lattes.cnpq.br/3273672989988386; https://lattes.cnpq.br/0959318786185727
This work has objective to show results of a didactic experience that consider the use of a dynamic geometric software in a restrict area of the Mathematic, named fractal . This study presents a great complexity and beauty in your geometric structures. Therefore, we present some fractals, in particular, the Pythagorean Tree that arouses the interest of students. For geometric constructions, we chose the GeoGebra software, based in the geometry lessons that we had in the course. Next, we explore one of the most famous theorems of the Plane Geometry, the Pythagoras Theorem, in addition of others mathematics contents, such as, counting. We also study the main trends connected to the informatics and we took advantages of the computational technology resource to assist the students with the construction and learning, including them in a new educational scenario based in the technology presence.
Investigação da ação bactericida de produtos naturais sobre a bactéria Xylella fastidiosa
(Universidade Federal de São Carlos, 2013-08-26) Silva, Danielle Fernandes da; Forim, Moacir Rossi; https://lattes.cnpq.br/1234565160573730; https://lattes.cnpq.br/8073510267574692
This work describes the study of natural compounds as potential bactericides for control of Xylella fastidiosa which causes the Citrus Variegated Chlorosis (CVC), a disease that causes large losses in brazilian citrus and still does not have a bactericidal specific in the market to combat it. The project was deveped in two stages. The first part of the work was done in vitro, where the compounds naringenina complexed with rutênio and magnésio, separately, hesperidina complexed with magnésio, azadirachtina, hesperidina and naringenina were tested as inhibitors of Xylella fastidiosa growth using the system of microdilution in culture media to detect the minimal inhibitory concetration of these compounds against the bacterium Xylella fastidiosa. These compounds showed, respectively, minimum inhibitory concentrations of 0,19 µM, 0,34 µM, 1,01 µM, 2,1 µM, 3,27 µM e 7,3 µM. In a second phase, the best results obtained in vitro were validated in Vivo experiments, where the bacterium was inoculated into healthy citros plants. After a period of manifestation of disease in plants, these were diagnosed by PCR analysis to identify which plants had been contaminated by the bacterial. After detecting diseased plants through the presence of Xylella fastidiosa s DNA, they were treated with those natural componds and their derivatives that have been tested in vitro. After a period of treatement, the plants to obsorb the metabolites and acted upon these bacteria, a analysis was perfomed by quantitative PCR (qPCR) comparing the amount of bacteria in plants before and after treatment with the bactericide, evaluating the occurrence or not, of the bacterium inibition. The following results were obtained: for naringenina complexed with Mg, 0,8 µM; naringenina complexed with Ru, 1,2 µM; azadirachtina, 1,4 µM; hesperidina, 1,8 µM; naringenina 3,9 µM and cuprum (positive control), 6,3 µM, this for 0,1% of life bacteria. The in vitro results consistent with the results in vivo.
Função colinérgica cardiorrespiratória no núcleo do trato solitário
(Universidade Federal de São Carlos, 2013-08-26) Furuya, Werner Issao; Zoccal, Daniel Breseghello; https://lattes.cnpq.br/1958567557189244; Colombari, Débora Simões de Almeida; https://lattes.cnpq.br/1684467594359403; https://lattes.cnpq.br/0143751393367471
The nucleus of the solitary tract (NTS) is the primary synaptic site of the peripheral baroreceptors and chemoreceptors. It has been shown that acetylcholine (ACh) microinjected into the NTS of rats induces hypotension and bradycardia. However, the contribution of cholinergic mechanisms at different NTS subnuclei (intermediate and commissural) as well as the cholinergic receptors blockade on the control of sympathetic (SNA) and phrenic (PNA) nerve activities have not been studied yet. In this study we assessed the role of ACh and its cholinergic receptors at the intermediate NTS (iNTS) and commissural NTS (cNTS) on the control of SNA, PNA and electrophysiological properties of these subnuclei neurons, as well as on baro and chemoreflex responses. Decorticated arterially-perfused in situ preparations of male juvenile rats were used to record SNA and PNA. Microinjections of ACh and cholinergic antagonists were performed into the iNTS or cNTS. Coronal slices of the brainstem containing either cNTS or iNTS subnuclei were obtained from male juvenile rats and used in whole cell patch clamp – current clamp recordings. It was observed that ACh microinjected into the iNTS inhibited both SNA and PNA. These effects were reduced by the pre-treatment with atropine (muscarinic antagonist) or mecamylamine (nicotinic antagonist). The cholinergic antagonists into the iNTS did not change the effects on SNA and PNA induced by baro and chemoreflex activation. In contrast, microinjections of ACh into the cNTS did not induce changes in SNA, but increased PNA. Despite the absence of changes in SNA, ACh into the cNTS changed the pattern of respiratory-sympathetic coupling. Both atropine and mecamylamine into the cNTS inhibited the ACh-induced tachypnea, but only mecamylamine inhibited the chemoreflex-induced tachypnea and the ACh-induced change in respiratory-sympathetic coupling. In vitro studies demonstrated that ACh promotes depolarization in both iNTS and cNTS neurons. Both muscarinic and nicotinic antagonism in the iNTS inhibited the ACh-induced depolarization. However, only nicotinic antagonist was effective in diminishing this response in the cNTS. The results suggest that ACh plays an important role in the control of cardiovascular and respiratory activities, with distinct functions between iNTS and cNTS. This cholinergic control involves activation of both muscarinic and nicotinic receptors within NTS, but only nicotinic receptors are involved in the chemoreflex tachypneic response.