The present study examined the rheological blood velocity profile in the conduit femoral artery during rhythmic muscle contractions at different muscle forces. Eight healthy volunteers performed one-legged, dynamic knee-extensor exercise at work rates of 5, 10, 20, 30, and 40 W at 60 contractions per minute. The time and space-averaged, amplitude-weighted mean (V(mean)) and maximum (V(max)) blo...

STUDY DESIGN A prospective study in which patients with idiopathic scoliosis were examined longitudinally by radiographic and electromyographic measurements according to a protocol. OBJECTIVES To measure the growth velocity of the spine and the electromyographic ratio of the paraspinal muscles to determine their relation to progression of the scoliotic curve. SUMMARY OF BACKGROUND DATA Seve...

Previous research has indicated that observers use differences between velocities and ratios of velocities to judge the depth within a moving object, although depth cannot in general be determined from these quantities. In four experiments we examined the relative effects of velocity difference and velocity ratio on judged depth within a transparent object that was rotating about a vertical axi...

Methods Seventy fetuses at 19 to 28 weeks of gestation with an IEF and 63 controls were screened using two-dimensional and power Doppler echocardiography. DV wave velocities, DV velocity ratios, and diastolic time intervals were measured. The aortic peak velocity, pulmonary artery peak velocity, atrioventricular early-diastolic filling velocity (E), atrial contraction velocity (A), and E/A rati...

The rise velocity of long gas bubbles (Taylor bubbles) in round tubes is modeled by an ovary ellipsoidal cap bubble rising in an irrotational flow of a viscous liquid. The analysis leads to an expression for the rise velocity which depends on the aspect ratio of the model ellipsoid and the Reynolds and Eötvös numbers. The aspect ratio of the best ellipsoid is selected to give the same rise velo...

OBJECTIVE The aim of this study was to determine whether sonographic fetal pulmonary artery flow velocity waveforms correlate with amniotic fluid biomarkers of fetal lung maturity. STUDY DESIGN We studied women with singleton pregnancies undergoing clinically indicated amniocentesis for fetal lung maturity at Yale-New Haven Hospital. Fetal pulmonary artery flow velocity measurements, includin...

Results: In conventional Doppler echocardiography, Mitral A-wave velocity and deceleration time were higher, and E/A ratio was lower in patients with BD (p=0.002, p=0.02, and p=0.006, respectively). Mitral E-wave velocity and isovolumetric relaxation time were comparable between groups (p>0.05). In TDI examination, E′/A′ ratio measured from lateral mitral annulus was lower, and A′ velocity meas...

River confluence is a common feature of most irrigation and drainage channels and river systems, where tributary conflicts the main channel. In these section, rapid changes in velocity and discharge, sediment distribution and flow turbulent result in a deep confluence scour, a bar point in the separation zone at downstream of junction corner  and finally vortex flow. Thus, the main goal of this...

BACKGROUND Prior studies have demonstrated regional left atrial late gadolinium enhancement (LGE) heterogeneity on magnetic resonance imaging. Heterogeneity in regional conduction velocities is a critical substrate for functional reentry. We sought to examine the association between left atrial conduction velocity and LGE in patients with atrial fibrillation. METHODS AND RESULTS LGE imaging a...