Actin stress fibers (SFs) of cells cultured on cyclically stretched substrate tend to reorient in the direction in which a normal strain of substrate becomes zero. However, little is known about the mechanism of this reorientation. Here we investigated the effects of cyclic stretch waveform on SF reorientation in osteoblastic cells. Cells adhering to silicone membranes were subjected to cyclic ...

BACKGROUND Orthodontic tooth movement is a complex procedure that occurs due to various biomechanical changes in the periodontium. Optimal orthodontic forces yield maximum tooth movement whereas if the forces fall beyond the optimal threshold it can cause deleterious effects. Among various types of tooth movements intrusion and lingual root torque are associated with causing root resoprtion, es...

By analyzing the equilibrium shape of vacancy islands on the Ge(001) surface we have determined the surface stress anisotropy, i.e., the difference between the compressive stress component along the substrate dimer rows and the tensile stress component perpendicular to the substrate dimer rows. In order to extract the surface stress anisotropy we have used a model recently put forward by Li et ...

This paper derives conditions for localized deformation for a transversely isotropic constitutive relation intended to model the response of geological materials in the axisymmetric compression test. The analysis considers the possibility of shear bands, with dilation or compaction, and pure compaction bands. The latter are planar zones of localized pure compressive deformation (without shear) ...

Mechanical stress produced by orthodontic forces is a factor in the remodeling of periodontal ligaments (PDLs) and alveolar bone. It has been reported that the expression of a number of cytokines associated with osteoclastogenesis is upregulated when compressive forces act on osteoblasts and PDL cells. The present study investigated the effects of compressive forces on the formation of osteocla...

The compressive properties of human enamel and dentin have been reported by Stanford, Paffenbarger, Kumpula, and Sweeney.' The elastic modulus of occlusal, side, and cusp enamel was reported to be 1.8, 6.0, and 8.2 X 106 psi, respectively. The corresponding values for the proportional limit were 16,800, 21,000, and 34,200 psi and, for the compressive strength, 19,400, 28,300, and 40,200 psi. An...

For brittle fracture behaviour of carbon fibre reinforced plastics (CFRP) under compression, several approaches exist, which describe different mechanisms during failure, especially at stress intensifications. The failure process is not only initiated by the buckling fibres, but a shear driven fibre compressive failure beneficiaries or initiates the formation of fibres into a kink-band. Startin...

BACKGROUND The DASCOR device has recently been introduced as an innovative nucleus replacement alternative for the treatment of low-back pain caused by degenerative intervertebral disc disease. The purpose of this study was to characterize, through a series of preclinical mechanical bench and biomechanical tests, the effectiveness of this device. METHODS A number of samples were created using...