This paper presents an enhanced version of our previous algorithm for point-wise tracking and analysis of cardiac motion based on 3D active mesh model. In the present software, a new 3D active surface model based on curve evolution techniques and level sets is used for automatizing the segmentation of endocardial boundary in the left ventricle in the first phase of cardiac cycle. Furthermore, c...

Effect of temperature on hydrodynamics of bubbling gas-solid fluidized beds was investigated.  Experiments were carried out in the range of 25-600 ºC and different superficial gas velocities in the range of 0.17-0.78 m/s with sand particles. Time-position trajectory of particles was obtained by radioactive particle tracking technique. These data were used for determination of mean velocitie...

Ultrasonography for the noninvasive assessment of tissue properties has enjoyed widespread success. With the growing emphasis in recent years on arteriovenous fistulae (AVFs) for dialysis vascular access in patients with end-stage renal disease, and on reducing AVF failures, there is increasing interest in ultrasound for the preoperative evaluation of the mechanical and elastic properties of ar...

Accurate estimation of heart wall dense field motion and deformation could help to better understand the physiological processes associated with ischemic heart diseases, and to provide significant improvement in patient treatment. We present a new method of estimating left ventricular deformation which integrates instantaneous velocity information obtained within the mid-wall region with shape ...

Because effective navigation in 3D virtual environments (VEs) depends on the specifics of the travel techniques and the display system, we compared two travel techniques (steering and target-based) and two display conditions—a high-fidelity setup (a four-wall display with stereo and head-tracking) and a lower-fidelity setup (a single wall display without stereo or head-tracking). In a controlle...

BACKGROUND Echocardiographic evaluation of left ventricular (LV) strain and strain rate (SR) by 2D speckle tracking may be useful tools to assess chronic thromboembolic pulmonary hypertension (CTEPH) severity as well as response to successful pulmonary thromboendarterectomy (PTE). METHODS We evaluated 30 patients with CTEPH before and after PTE using 2D speckle tracking measurements of LV rad...

Through wall tracking of moving targets is of interest for rescue, surveillance and security operations. A useful method applies an ultra-wideband radar approach for this purpose since electromagnetic waves in the lower GHzrange penetrate most common building materials, such as bricks, wood, dry walls, concrete and reinforced concrete. However in consequence of a wall effect, estimated target t...

BACKGROUND Two-dimensional speckle tracking provides valuable information for regional wall motion abnormalities. The purpose of this study was to determine the diagnostic value of left ventricular longitudinal strain and torsion to diagnose coronary artery disease during dobutamine stress echocardiography. METHODS We studied 100 patients (mean age 60.8 ± 10.7 years, 72 male) with known or su...

We combine well established particle tracking with wall surface measurements using tomographic scanning and present results for the non-stationary 4D flow field within an abdominal aortic aneurysm (AAA) phantom. It was manufactured from an optically homogeneous but slightly opaque silicone having an index of refraction n = 1.414. The fluid used is a mixture of water and glycerol to match the in...

This study presents high temperature water-only continuous flowthrough pretreatment coupled with nuclear magnetic resonance (NMR) as a promising analytical tool to examine the plant cell wall, to understand its recalcitrance (i.e., cell wall resistance to deconstruction), and to probe the chemistry occurring during batch pretreatment of biomass. (13)C-enriched corn stover stems were pretreated ...