2 resultados para Longitudinal axis

em University of Queensland eSpace - Australia


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Subclinical left ventricular (W) dysfunction may be identified by reduced longitudinal contraction. We sought to define the effects of subclinical LV dysfunction on radial contractility in 53 patients with diabetes mellitus with no LV hypertrophy, normal ejection fraction and no ischaemia as assessed by dobutamine echocardiography, in comparison with age-matched controls. Radial peak myocardial systolic velocity (S-m) and early diastolic velocity (E-m), strain and strain rate were measured in the mid-posterior and mid-anteroseptal walls in parasternal views and each variable was averaged for individual patients (radial contractility). These variables were also measured in the mid-posterior and mid-anteroseptal walls in the apical long-axis view and each variable was averaged for individual patients (longitudinal contractility). Mean radial S-m, strain and strain rate were significantly increased in diabetic patients (2.9+/-0.6 cm/s, 28+/-5% and 1.8+/-0.4 s(-1) respectively) compared with controls (2.4+/-0.7 cm/s, 23+/-4% and 1.6+/-0.3 s(-1) respectively; all P<0.001), but there was no difference in E-m (3.3&PLUSMN;1.2 compared with 3.1&PLUSMN;1.1 cm/s, P=not significant). In contrast, longitudinal S-m, E-m, strain and strain rate were significantly lower in diabetic patients (3.6&PLUSMN;1.1 cm/s, 4.3&PLUSMN;1.6 cm/s, 21&PLUSMN;4% and 1.6&PLUSMN;0.3 s(-1) respectively) than in controls (4.3&PLUSMN;1.0 cm/s, 5.7&PLUSMN;2.3 cm/s, 26&PLUSMN;4% and 1.9&PLUSMN;0.3 s(-1) respectively; all P<0.00 1). Thus radial contractility appears to compensate for reduced longitudinal contractility in subclinical LV dysfunction occurring in the absence of ischaemia or LV hypertrophy.

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In this paper, we applied a version of the nonlocal density functional theory (NLDFT) accounting radial and longitudinal density distributions to study the adsorption and desorption of argon in finite as well as infinite cylindrical nanopores at 87.3 K. Features that have not been observed before with one-dimensional NLDFT are observed in the analysis of an inhomogeneous fluid along the axis of a finite cylindrical pore using the two-dimensional version of the NLDFT. The phase transition in pore is not strictly vapor-liquid transition as assumed and observed in the conventional version, but rather it exhibits a much elaborated feature with phase transition being complicated by the formation of solid phase. Depending on the pore size, there are more than one phase transition in the adsorption-desorption isotherm. The solid formation in finite pore has been found to be initiated by the presence of the meniscus. Details of the analysis of the extended version of NLDFT will be discussed in the paper. (C) 2004 American Institute of Physics.