The equivalence of the energy velocity and the group velocity is often taught in university physics. An early proof of the equivalence of the two velocities for one-dimensional water waves was given by Rayleigh [1]. In the 1950s and 1960s many studies [2}4] were done to show the equivalence of the two velocities for more general systems. Later, in the 1990s, Awati and Howes raised a question as...

The aim of this study was to determine the normal value of brachial-ankle pulse wave velocity (baPWV) and carotid-femoral pulse wave velocity (cfPWV) according to age group, gender, and the presence of cardiovascular risk factors in healthy Koreans, and to investigate the association between PWV and risk factors such as prehypertension, dyslipidemia, smoking, and obesity. We measured an arteria...

Noninvasive evaluation of brachial artery diameter (pulsed Doppler velocimetry) and pulse wave velocity (strain gauge mechanography) was performed in 23 normal subjects and 49 patients with uncomplicated essential hypertension. Pulsatile arterial function was described in terms of derived characteristic impedance and arterial compliance. Compared with normal controls, hypertensive patients had ...

The central arteries stiffen with age, causing hemodynamic alterations that have been associated with cardiovascular events. Changes in body fat with age may be related to aortic stiffening. The association between vascular stiffness and body fat was evaluated in 2488 older adults (mean age, 74 years; 52% female; 40% black) enrolled in the Study of Health, Aging, and Body Composition (Health AB...

OBJECTIVE The effects of acute hemodialysis session on pulse wave velocity are conflicting. The aim of the current study was to assess the acute effects of ultrafiltration on the aortic mechanical properties using carotid-femoral (aortic) pulse wave velocity and pulse propagation time. METHODS A total of 26 (12 women, 14 men) consecutive patients on maintenance hemodialysis (mean dialysis dur...

We examined whether the presence of an increasing number of metabolic syndrome "disorders" was associated with an increasing pulse wave velocity, which is recognized as a marker of cardiovascular risk, and evaluated whether an elevated plasma C-reactive protein level augments this increasing pulse wave velocity. Using a cross-sectional study design, C-reactive protein, metabolic syndrome-relate...

Action potential duration (APD) restitution, which relates APD to the preceding diastolic interval (DI), is a useful tool for predicting the onset of abnormal cardiac rhythms. However, it is known that different pacing protocols lead to different APD restitution curves (RCs). This phenomenon, known as APD rate dependence, is a consequence of memory in the tissue. In addition to APD restitution,...

The stress wave propagation in a generalized thermoelastic polygonal plate of inner and outer cross sections is studied using the Fourier expansion collocation method. The wave equation of motion based on two-dimensional theory of elasticity is applied under the plane strain assumption of generalized thermoelastic plate of polygonal shape, composed of homogeneous isotropic material.  The freque...

Conventional definitions of velocities associated with the propagation of modulated waves cannot clearly describe the behavior of the wave packet in a multidimensional dispersive medium. The conventional definition of the phase velocity, which is perpendicular to the wave front, is a special case of the generalized phase velocity defined in this work, since there exist an infinite number of sol...

The current study presents a new protocol for local pulse wave velocity (PWV) measurement using dynamic MR sequences, which have a high temporal resolution (TR < 6 ms). MR images were obtained at two positions along the common carotid artery, separated by a distance of 5 cm. In each phase of a MR series, carotid region was automatically extracted and then its area distension waveform could be o...