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This study was designed to examine the effects of the anastomotic angle on the flow and haemodynamic parameter distribution patterns of the proximal anastomoses, with emphasis on identifying site-specific haemodynamic features that could reasonably be expected to trigger the initiation and further development of anastomotic intimal hyperplasia. Particle image velocimetry measurements were carried out with three simplified glass proximal models under a physiological flow condition. The results revealed that the disturbed flow and the induced shear stress patterns including low recirculation flow, stagnation point, high wall shear stress, high temporal wall shear stress gradient, low time-averaged wall shear stress (TAWSS), and high oscillating shear index (OSI) occurred around the anastomotic joints and the flow field at proximal anastomosis was strongly affected by the anastomotic angle. Among the three models investigated, the 45° backward anastomosis is found to have a smaller low-recirculation-flow region along the graft inner wall, non-stationary stagnation, and separation points, a higher TAWSS and smaller high-OSI low-TAWSS and low-OSI high-TAWSS regions.

A mesh-free radial basis function method is presented to analyze the static deflection, free vibration and buckling analysis of laminated composite plates using third-order shear deformation plate theory. The problem domain represented by a set of scattered nodes in its support domain based on the radial basis functions with polynomial reproduction. Based on the third-order shear deformation plate theory, variation forms of the static, free vibration and buckling system equations are formulated in terms of displacements and are discretized. The shape function thus constructed possesses a delta function property, and hence the essential boundary conditions can be implemented with ease as in the conventional finite element method. Several numerical examples are presented to demonstrate the convergence, accuracy and validity of the proposed method. Comparison of results with the exact solution as well as finite element method in the literature suggests that the mesh free radial basis function method yields an effective solution method for laminated composite plates. The effects of the modulus ratio, side-to-thickness ratio, shear correction factor and boundary conditions are discussed.

Previously aortic stiffness is frequently assessed through pulse pressure and pulse wave velocity (PWV) measurements. However, these methods need aortic pressure obtained by catheterization. A new model has been developed to rapidly determine the aortic pressure profile and simultaneously calculate aortic stiffness. Comparison between the aortic pressure result obtained from this and catheterization data demonstrates good agreement, while this method is non-invasive. This totally non-invasive method should be useful in assessing arteriosclerotic disease in clinical setting.