The present paper is an attempt to use ultrasonic velocity measurements to characterize the texture of an aluminum-magnesium alloy ( Al 5xxx ) and to compare the results with orientation imaging microscopy ( OIM ) results. The results are characterized in terms of three orientation distribution coefficients ( ODC's ), W400 , W420 , and W440 , each of which describes a particular forming anisotr...

We have developed a set of numerical tools for the quantitative analysis of defect dynamics in quasiperiodic structures. We have applied these tools to study dislocation motion in the dynamical equation of Lifshitz and Petrich [Phys. Rev. Lett. 79 (1997) 1261] whose steady state solutions include a quasiperiodic structure with dodecagonal symmetry. Arbitrary dislocations, parameterized by the h...

Buoyancy-induced (Rayleigh-Bénard) convection of a fluid between two horizontal plates is a central paradigm for studying the transition to complex spatiotemporal dynamics in sustained nonequilibrium systems. To improve the analysis of experimental data and the quantitative comparison of theory with experiment, we have developed a three-dimensional finite-difference code that can integrate the ...

The signs of radiofrequency phases and frequencies used in are also fraught with subtle sign problems, for example, NMR are examined carefully. Some fundamental problems with cross-correlated relaxation (4–9) , nuclear demagnetizing current usage are exposed by simple examples. The entire chain of field effects (10–13) , and phase or frequency shifts induced events leading to the NMR spectrum i...

Structural defects in ion crystals can be formed during a linear quench of the transverse trapping frequency across the mechanical instability from a linear chain to a zigzag structure. The density of defects after the sweep can be conveniently described by the Kibble–Zurek mechanism (KZM). In particular, the number of kinks in the zigzag ordering can be derived from a time-dependent Ginzburg–L...

Deep 21-cm H i line observations of the Virgo cluster spiral galaxy NGC 4569 have been obtained with the VLA in its D configuration and with the Effelsberg 100-m telescope. A low surface density arm was discovered in the west of the galaxy, whose velocity field is distinct from that of the overall disk rotation. The observed gas distribution, velocity field, and velocity dispersion are compared...

The concept of "normalized velocity" has been applied in this study to the echocardiographic (echo) assessment of left ventricular (LV) function in 87 patients. The following normalized velocities were calculated from the ultrasound recording of LV wall motion: 1) the mean circumferential fiber shortening rate (mean VCF), 2) the mean normalized posterior wall velocity (Vpw), and 3) the mean nor...

Gait dysfunction and falling are major sources of disability for patients with advanced Parkinson's disease (PD). It is presently thought that the fundamental defect is an inability to generate normal stride length. Our data suggest, however, that the basic problem in PD gait is an impaired ability to match step frequency to walking velocity. In this study, foot movements of PD and normal subje...

Background: Atrial septal defect is a common congenital heart anomaly results in hemodynamically significant right ventriclular volume overload and an increase the pulmonary venous flow.
 Aim: Evaluate changes of flow parameters after transcatheter closure secundum atrial defect.
 Patients Methods: 50 patients with aged from 3.5 to 31 years were included study. Pulmonary Doppler ventr...