Learn More
The developing vertebrate gut tube forms a reproducible looped pattern as it grows into the body cavity. Here we use developmental experiments to eliminate alternative models and show that gut looping morphogenesis is driven by the homogeneous and isotropic forces that arise from the relative growth between the gut tube and the anchoring dorsal mesenteric(More)
Particle tracking techniques are often used to assess the local mechanical properties of cells and biological fluids. The extracted trajectories are exploited to compute the mean-squared displacement that characterizes the dynamics of the probe particles. Limited spatial resolution and statistical uncertainty are the limiting factors that alter the accuracy(More)
Percutaneous transluminal balloon catheter aortic valvuloplasty (PTAV) was carried out in three elderly patients with acquired severe aortic valve stenosis. Transvalvular systolic pressure gradient was considerably decreased at the end of the procedure, during which there were no complications. Increased valve opening was confirmed by angiography and(More)
The efficacy, morbidity, and 1-year follow-up of balloon aortic valvuloplasty in patients with low ejection fraction (less than 40%) were studied on a consecutive series of 55 patients (mean age, 77 years) treated from September 1985 to February 1987. Because of their age (20 patients greater than 80 years old), poor left ventricular function, and(More)
The role of a finite exposure time sigma on measuring rheological properties using microrheology techniques is theoretically investigated. We concentrate on studying fluid models displaying a plateau in the mean-squared displacement (MSD) of the embedded probe particle. A model is developed to compare the resulting experimentally measured MSD of the(More)
Video microscopy can be used to simultaneously track several microparticles embedded in a complex material. The trajectories are used to extract a sample of displacements at random locations in the material. From this sample, averaged quantities characterizing the dynamics of the probes are calculated to evaluate structural and/or mechanical properties of(More)
Hydrogels formed from the self-assembly of oligopeptides are being extensively studied for biomedical applications. The kinetics of their gelation, as well as a quantitative description of the forces controlling the rate of assembly has not yet been addressed. We report here the use of multiple particle tracking to measure the self-assembly kinetics of the(More)
The authors describe a rational approach to an important step in video microscopy particle tracking called noise discrimination. Using the morphology of the brightness profiles produced by the particles, false and dubious detections are eliminated from the valid tracking data. This selection process is found to affect the spatial resolution ␧ and the depth(More)
The Kazakhstan-Siberia nursery (KASIB) for the spring wheat improvement under the aegis of the CIMMYT (International Maize and Wheat Improvement Center) has been identified for a ten-year period by five cultivar blocks analyzed for the gliadin composition (1B/1R traslocation), compositions of high-molecular weight (HMW) and low-molecular weight (LMW)(More)
  • 1