BACKGROUND The combination of early transmitral inflow velocity and mitral annular tissue Doppler imaging (E/Em ratio) is widely applied to noninvasively estimate left ventricular (LV) filling pressures. However E/Em ratio has a significant gray zone and its accuracy in patients with heart failure is debated. Left atrial (LA) deformation analysis by speckle tracking echocardiography (STE) was r...

Developmental changes in left and right ventricular diastolic filling patterns were determined noninvasively in isoflurane-anesthetized outbred ICR mice. Blood velocities in the mitral and tricuspid orifices were recorded in 16 embryos at days 14.5 (E14.5) and 17.5 of gestation (E17.5) using an ultrasound biomicroscope and also serially in three groups of postnatal mice aged 1-7 days (n = 23), ...

BACKGROUND The ratio of early transmitral flow velocity to early diastolic velocity of the mitral annulus (E/e') is an indicator of diastolic function that correlates well with left ventricular (LV) filling pressure and is relatively independent of systolic function and rhythm abnormalities. We prospectively evaluated the predictive value of E/e' for postoperative outcome in patients undergoing...

To examine whether alterations in right ventricular filling dynamics occur with increasing age and to compare right and left ventricular filling in normal subjects, pulsed Doppler echocardiographic studies were performed at the tricuspid and mitral anuli in 50 normal volunteers (23 males and 27 females) with an age range of 5-66 years. An age-related decrease in peak early filling velocity, inc...

Changes in synaptic connectivity patterns through the formation and elimination of dendritic spines may contribute to structural plasticity in the brain. We characterize this contribution quantitatively by estimating the number of different synaptic connectivity patterns attainable without major arbor remodeling. This number depends on the ratio of the synapses on a dendrite to the axons that p...

To assess right ventricular (RV) diastolic filling in children with pulmonary stenosis (PS), 14 patients (mean age 5.1 years) were examined immediately before and after pulmonary balloon valvuloplasty. Fourteen normal children (mean age 4.8 years) were also studied. From the tricuspid valve inflow Doppler study, the following measurements were made at peak inspiration: peak velocities at rapid ...

Pulsating heat pipe is an efficient heat exchange device which is being used for cooling and heating recovery. In the present work, we made a closed-loop pulsating heat pipe with six U-turns and we used water in our system. Moreover the use of water-Fe3O4 nanofluid was studied with two different filling ratios 40% and 50% and 1% mass concentration. At the end we calculated heat resistance and h...

Pulsating heat pipe is an efficient heat exchange device which is being used for cooling and heating recovery. In the present work, we made a closed-loop pulsating heat pipe with six U-turns and we used water in our system. Moreover the use of water-Fe3O4 nanofluid was studied with two different filling ratios 40% and 50% and 1% mass concentration. At the end we calculated heat resistance and h...

The use of the two-phase closed thermosyphons (TPCTs) is increasing for many heat transfer applications. In this study, the development of a numerical model is presented with the purpose of determining the transient characteristics of a TPCT. The model includes the heat transfer through the wall, vapour core, liquid pool and the falling condensate film. The complete two-dimensional conservation...