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Filling Fraction (filling + fraction)
Selected AbstractsEchocardiographic Doppler Evaluation of Left Ventricular Diastolic Filling in Older, Highly Trained Male Endurance AthletesECHOCARDIOGRAPHY, Issue 1 2000PETER R. JUNGBLUT M.D. Previously published data have suggested that endurance training does not retard the normative aging impairment of early left ventricular diastolic filling (LVDF). Those studies, suggesting no effect of exercise training, have not examined highly trained endurance athletes or their LVDF responses after exercise. We therefore compared LVDF characteristics in a group of older highly trained endurance athletes (n= 12, mean age 69 years, range 65,75) and a group of sedentary control subjects (n= 12, mean age 69 years, range 65,73) with no cardiovascular disease. For all subjects, M-mode and Doppler echocardiographic data were obtained at rest. After baseline studies, subjects underwent graded, maximal cardiopulmonary treadmill exercise testing using a modified Balke protocol. Breath-by-breath respiratory gas analysis and peak exercise oxygen consumption (VO2max) measurements were obtained. Immediately after exercise and at 3,6 minutes into recovery, repeat Doppler echocardiographic data were obtained for determination of LVDF parameters. VO2max (44 ± 6.3 vs 27 ± 4.2 mllkglmin, P< 0.001), oxygen consumption at anaerobic threshold (35 ± 5.4 vs 24 ± 3.8 mllkglmin, P< 0.001), exercise duration (24 ± 3 vs 12 ± 6 minutes, P< 0.001), and left ventricular mass index (61 ± 13 vs 51 ± 7.8 kglm2, P< 0.05) were greater in endurance athletes than in sedentary control subjects, whereas body mass index was lower (22 ± 1.7 vs 26 ± 3.4 kglm2, P< 0.001). No differences in any of the LVDF characteristics were observed between the groups with the exception of a trend toward a lower atrial filling fraction at rest in the endurance athlete group versus the control subjects (P= 0.07). High-intensity endurance exercise training promotes exceptional peak exercise oxygen consumption and cardiovascular stamina but does not appear to alter normative aging effects on left ventricular diastolic function. (ECHOCARDIOGRAPHY, Volume 17, January 2000) [source] Pore-Filling of Spiro-OMeTAD in Solid-State Dye Sensitized Solar Cells: Quantification, Mechanism, and Consequences for Device PerformanceADVANCED FUNCTIONAL MATERIALS, Issue 15 2009I-Kang Ding Abstract In this paper, the pore filling of spiro-OMeTAD (2,2,,7,7,-tetrakis-(N,N -di- p -methoxyphenylamine)9,9,-spirobifluorene) in mesoporous TiO2 films is quantified for the first time using XPS depth profiling and UV,Vis absorption spectroscopy. It is shown that spiro-OMeTAD can penetrate the entire depth of the film, and its concentration is constant throughout the film. We determine that in a 2.5-µm-thick film, the volume of the pores is 60,65% filled. The pores become less filled when thicker films are used. Such filling fraction is much higher than the solution concentration because the excess solution on top of the film can act as a reservoir during the spin coating process. Lastly, we demonstrate that by using a lower spin coating speed and higher spiro-OMeTAD solution concentration, we can increase the filling fraction and consequently the efficiency of the device. [source] Rare-Earth Spontaneous Emission Control in Three-Dimensional Lithium Niobate Photonic CrystalsADVANCED MATERIALS, Issue 34 2009Airán Ródenas Spontaneous emission inhibition of erbium ions at 1.5,µm wavelength is obtained by tailoring direct femtosecond-laser-written 3D photonic structures inside lithium niobate laser crystals. This technique allows for engineering of the structure symmetry and filling fraction by spatially inscribing laser-induced amorphous voxels inside the crystalline sample. [source] The effects of ACE inhibitor therapy on left ventricular myocardial mass and diastolic filling in previously untreated hypertensive patients: A Cine MRI studyJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2001U. Hoffmann MD Abstract Cardiac remodeling in case of hypertension induces hypertrophy of myocytes and elevated collagen content and, subsequently, impaired diastolic filling of the left ventricle. The purpose of this prospective study was to evaluate changes of left ventricular (LV) myocardial mass, as well as diastolic filling properties, in hypertensive patients treated with the ACE inhibitor fosinopril. Sixteen hypertensive patients with echocardiographically documented LV hypertrophy and diastolic dysfunction received fosinopril (10,20 mg daily). Measurements of LV myocardial mass and properties of diastolic filling (peak filling fraction (PFF); peak filling rate (PFR)) were performed prior to medication, as well as after 3 and 6 months of therapy using cine magnetic resonance imaging (MRI). Ten healthy subjects served as a control group. LV myocardial mass (g/m2) decreased continuously within 3,6 months of follow-up by 32% (148 ± 40 vs. 120 ± 26 vs. 101 ± 22 g/m2; P < 0.0001/0.005). The extent of regression correlated to the severity of LV hypertrophy at baseline (r = 0.77; P < 0.004). Early diastolic filling increased significantly within 6 months of therapy (PFF (%): 36 ± 6 vs. 61 ± 7, P < 0.0001; PFR (mL/second): 211 ± 48 vs. 282 ± 48, P < 0.001). Cine MRI can be used to assess the time course of pharmacological effects on cardiac remodeling in the course of hypertension. ACE inhibitor therapy results in a significant reduction of LV mass within 3 months and is accompanied by a normalization of diastolic filling that is completed after 6 months. J. Magn. Reson. Imaging 2001;14:16,22. © 2001 Wiley-Liss, Inc. [source] Particle energies and filling fractions of radio bubbles in cluster coresMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2004R. J. H. Dunn ABSTRACT Using Chandra images of cluster cores with clear radio bubbles, we have determined k, which is the ratio of the total particle energy to that of the electrons radiating between 10 MHz and 10 GHz. Radiative and dynamical constraints on the bubbles indicate that the ratio of the energy factor, k, to the volume filling factor, f, lies within the range 1 ,k/f, 1000. Assuming pressure equilibrium between the radio-emitting plasma and the surrounding X-ray gas, none of the lobes has equipartition between relativistic particles and magnetic field. There is no evidence for any dependence of the upper limit of the k/f ratio on any physical parameter of the cluster or the radio source. The distribution of the upper limit on k/f appears to be bimodal, the value being ,3 for some clusters and ,300 for the others. We show that this may be due to the composition of the jet which forms the bubbles, the variation in the volume filling fraction or variation in the amount of reacceleration occurring in the bubble. [source] | |||||||||||||