In the present research, the mixed-mode fracture mechanics analysis in a plate with central hole under tensile loading is considered. It is assumed that a plate containing two symmetrical hole-edge cracks is bonded with two dissimilar planes. The stress intensity factors at the crack tips are calculated. The problem is modeled in Casca software and this model is analyzed with Franc software. Th...

Acrylic (polymethylmethacrylate or PMMA) bone cement was modified by the addition of high-strength zirconia fibers with average lengths of 200 microm and diameters of 15 microm or 30 microm. A novel emulsion polymerization process was developed to encapsulate individual fibers in PMMA. Improvements in tensile and compressive properties as well as in fracture toughness were investigated upon inc...

We have described a very fast approach for the formation of α–Fe2O3 nanorods by a simple reaction of iron with water at very low temperature of 190oC. It is shown that the nanorods have diameters ranging from 70-120nm and their typical lengths are in micrometers. The initial formation and subsequent growth of α–Fe2O3 nanostructures may be explained by the iron metal corrosion mechanism. There a...

The contractile behavior of cells is relevant in understanding wound healing and scar formation. In tissue engineering, inhibition of the cell contractile response is critical for the regeneration of physiologically normal tissue rather than scar tissue. Previous studies have measured the contractile response of cells in a variety of conditions (e.g. on two-dimensional solid substrates, on free...

We here develop a continuum-mechanical formulation and generalization of the Navier– Stokes-α equation based on a general framework for fluid-dynamical theories involving gradient dependencies (Fried & Gurtin 2005). That generalization entails two additional material length scales: one of energetic origin, the other of dissipative origin. In contrast to Lagrangian averaging, our formulation del...

A localization-induced cohesive model has been proposed for shear band evolution, crack growth, and fracture. Strain gradient theory has been applied to establish the criterion of the onset of localization and the governing equation in the post-bifurcation stage. Analytical solutions in one-dimensional case are used to establish the ‘‘traction-separation’’ law, in which strain gradient and mate...

Objective The aim of this study was to examine the properties of fiber-reinforced composite and stainless steel twisted retainers for orthodontic retention. Methods Three different span lengths (5.0, 8.0, and 14.0 mm) of fiber-reinforced composite were investigated. The three fiber-reinforced composite retainer groups were subdivided according to the storage condition (dry and wet), resulting...

background: stature reconstruction from skeletal remains forms part of the forensic anthropological analysis for the purpose of identification of an individual. material and methods: it is well documented from the previous studies that intact femur has the highest correlation with stature and as such widely used in deriving the regression equations. however, the femur is not always recovered in...