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O presente trabalho foi desenvolvido na UFPR - Campus Palotina, no Paraná, e em três propriedades rurais do mesmo município, durante o período de novembro de 1997 a maio de 1999. O experimento foi delineado com os objetivos de avaliar: a) a flutuação de larvas de Dermatobia hominis (Linnaeus Jr., 1781) em bovinos da raça Holandesa Preto e Branco criados no município de Palotina, e a distribuição desses ectoparasitos na superfície corporal de bovinos; e b) a sazonalidade dos principais dípteros vetores de ovos de D. hominis. Para a captura dos insetos vetores, foram utilizados dois tipos de armadilhas: MAGOON e orientada pelo vento (wind oriented trap = WOT). Um total de 346 larvas foram expulsas por meio de compressão manual, sendo que a intensidade de larvas foi maior no lado esquerdo do animal, onde foi constatado um total de 240 nódulos (69,36%). Analisadas as freqüências de nódulos de berne nos animais, ficou demonstrado que houve diferença significativa (p>0,001) na tendência parasitária. Três regiões corpóreas foram mais parasitadas. A primeira é formada pelos membros torácicos, paletas e costelas; a segunda é formada pelo pescoço e flancos, e a terceira, formada pelas regiões dos membros pélvicos, barbela, ventre, cauda e tórax. Durante o período experimental foram capturados, nas armadilhas WOT e de MAGOON, 5.887 dípteros pertencentes a diferentes famílias. Verificou-se que as famílias Calliphoridae, Sarcophagidae e Muscidae foram as mais prevalentes.

The present work is about the application of wall shear stress descriptors - time averaged wall shear stress (TAWSS), oscillating shear index (OSI) and relative residence time (RRT) - to the study of blood flow in the left coronary artery (LCA). These descriptors aid the prediction of disturbed flow conditions in the vessels and play a significant role in the detection of potential zones of atherosclerosis development. Hemodynamic descriptors data were obtained, numerically, through ANSYS® software, for the LCA of a patient-specific geometry and for a 3D idealized model. Comparing both cases, the results are coherent, in terms of location and magnitude. Low TAWSS, high OSI and high RRT values are observed in the bifurcation - potential zone of atherosclerosis appearance. The dissimilarities observed in the TAWSS values, considering blood as a Newtonian or non-Newtonian fluid, releases the importance of the correct blood rheologic caracterization. Moreover, for a higher Reynolds number, the TAWSS values decrease in the bifurcation and along the LAD branch, increasing the probability of plaques deposition. Furthermore, for a stenotic LCA model, very low TAWSS and high RRT values in front and behind the stenosis are observed, indicating the probable extension, in the flow direction, of the lesion.

Murray developed two laws for the geometry of bifurcations in the circulatory system. Based on the principle of energy minimization, Murray found restrictions for the relation between the diameters and also between the angles of the branches. It is known that bifurcations are prone to the development of atherosclerosis, in regions associated to low wall shear stresses (WSS) and high oscillatory shear index (OSI). These indicators (size of low WSS regions, size of high OSI regions and size of high helicity regions) were evaluated in this work. All of them were normalized by the size of the outflow branches. The relation between Murray's laws and the size of low WSS regions was analysed in detail. It was found that the main factor leading to large regions of low WSS is the so called expansion ratio, a relation between the cross section areas of the outflow branches and the cross section area of the main branch. Large regions of low WSS appear for high expansion ratios. Furthermore, the size of low WSS regions is independent of the ratio between the diameters of the outflow branches. Since the expansion ratio in bifurcations following Murray's law is kept in a small range (1 and 1.25), all of them have regions of low WSS with similar size. However, the expansion ratio is not small enough to completely prevent regions with low WSS values and, therefore, Murray's law does not lead to atherosclerosis minimization. A study on the effect of the angulation of the bifurcation suggests that the Murray's law for the angles does not minimize the size of low WSS regions., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The floristic variations of shrub and tree components were studied in two sites of Semideciduous Forest, initial forest and mature forest, located in the Mata do Paraíso Forest Reserve, in Viçosa, State of Minas Gerais, Southeastern Brazil, in order to analyze the floristic similarity and the correlations between environmental variables and the distribution of tree species in these forests. Individual trees with a diameter at breast height (DBH) > or = 4.8 cm were sampled in twenty 10 x 30 m plots (10 plots in each site). The plots were distributed systematically at 10 m intervals. The environmental variables analyzed were: the canopy openness and soil chemical and texture characteristics. The two forest sites showed clear differences in the levels of canopy openness and soil fertility, factors that reflect the floristic and successional differences of the shrub and tree component, revealed by the low similarity between these forests by cluster analysis. The canonical correspondence analysis (CCA) of environmental variables and species abundance indicated that the species in these forests studied are distributed under strong influence of canopy openness, moisture and soil fertility.