In this study, for the first time, we consider longitudinal motion of walls during peristalsis in a distensible tube and how affects backward (or retrograde) flow, i.e. peristaltic reflux. Building on analytical model developed by Shapiro et al. ( J. Fluid Mech. , vol. 37, no. 4, 1969, pp. 799–825) based lubrication theory, as two-dimensional infinite sinusoidal wavetrain. We develop an objecti...

Experiments were carried out in the dog by the use of experimental procedure which permits to assess independently changes in uretheral peristaltic frequency, bolus volume and intraluminal pressure and flow volume in order to characterize alpha-adrenoceptor subtypes involved in regulation of ureteral urine transport. Norepinephrine caused an increase in ureteral peristaltic frequency, an elevat...

How do infants extract milk during breast-feeding? We have resolved a century-long scientific controversy, whether it is sucking of the milk by subatmospheric pressure or mouthing of the nipple-areola complex to induce a peristaltic-like extraction mechanism. Breast-feeding is a dynamic process, which requires coupling between periodic motions of the infant's jaws, undulation of the tongue, and...

We carry out the effect of the pulsatile flow on peristaltic motion of an incompressible conducting micropolar fluid through porous medium in a channel bounded by flexible walls.Problem formulation in a wave frame of reference is presented. An oscillatory time dependent flux is being imposed on the peristaltic flow. The non-linear equations governing the flow through porous medium under the eff...

Peristaltic transport of a Williamson fluid in an asymmetric channel through porous medium is studied under long wavelength and low Reynolds number assumptions. The nonlinear governing equations of the peristaltic flow are solved using perturbation method. The solution for the stream function is obtained by neglecting inertia and curvature effects. The velocity distribution, the volume flow rat...

Introduction The entire abdomen is subject to complex motion patterns [1,2], comprising of breathing, heart and peristaltic motion. Insight into the contribution of each source is important to motility research and motion correction. This study proposes the use of continuously tagged imaging for motion assessment during free breathing, non-triggered, non-gated, dynamic MRI of the entire abdomen...