OBJECTIVE Both decreased glomerular filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness and the degree of GFR loss. Whether decreased GFR contributes to peripheral artery stiffness remains controversial. Moreover, data analyzed from a cohort of Chinese women are rare....

Left atrial muscle extends into the proximal third of the mitral valve (MV) anterior leaflet and transient tensing of this muscle has been proposed as a mechanism aiding valve closure. If such tensing occurs, regional stiffness in the proximal anterior mitral leaflet will be greater during isovolumic contraction (IVC) than isovolumic relaxation (IVR) and this regional stiffness difference will ...

Background Atherosclerosis and its associated diseases are constantly increasing in developed countries. Aortic stiffness is an indicator for atherosclerosis and is associated with mortality and morbidity especially in aortic abdominal aneurysms. For further evaluation of aortic stiffness, we examined n = 13 healthy volunteers using real-time magnetic-resonance imaging (RT-MRI) with highly unde...

We explored how the perception of stiffness can be distorted in Minimally Invasive Surgery. We combined a mechanical simulator with a haptic device, and implemented linear springs at the tip of the simulated laparoscopic device. To explore the influence of mechanical advantage on perception, we set different values of the ratio between internal and external length of the tool. We found that a n...

Anterior mitral leaflet stiffness during isovolumic contraction (IVC) is much greater than that during isovolumic relaxation (IVR). We have hypothesized that this stiffening is due to transient early systolic force development in the slip of cardiac myocytes in the annular third of the anterior leaflet. Because the atrium is excited before IVC and leaflet myocytes contract for < or = 250 ms, th...

The airway smooth muscle (ASM) layer within the airway wall modulates airway diameter and distensibility. Even in the relaxed state, the ASM layer possesses finite stiffness and limits the extent of airway distension by the radial force generated by parenchymal tethers and transmural pressure. Airway stiffness has often been attributed to passive elements, such as the extracellular matrix in th...

The mechanical properties of demineralized bovine cortical femur bone were investigated by cyclic loading-unloading compression in three anatomical directions (longitudinal, radial, transverse) within the physiological strain range. The loading responses in the radial and transverse directions were nearly linear up to 2% strain, while the response in longitudinal direction was strongly non-line...

The asymmetric problem of rocking rotation of a circular rigid disk embedded in a finite depth of a transversely isotropic half-space is analytically addressed. The rigid disk is assumed to be in frictionless contact with the elastic half-space. By virtue of appropriate Green's functions, the mixed boundary value problem is written as a dual integral equation. Employing further mathematical tec...