Despite recent advances in synthetic nanometer-scale tubular assembly, conferral of dynamic response characteristics to the tubules remains a challenge. Here, we report on supramolecular nanotubules that undergo a reversible contraction-expansion motion accompanied by an inversion of helical chirality. Bent-shaped aromatic amphiphiles self-assemble into hexameric macrocycles in aqueous solution...

Scattering by pulsating objects is discussed. In the case of the pulsating cylinder, its surface vibrates time-harmonically in the radial direction. The formalism is based on first-order / v c relativistic approximations, and on the assumption that the ambient media are not affected by the mechanical motion of the interface. This is conducive to simpler and amenable approximations. The cases an...

The objective of this study was to determine the impact of a total cavopulmonary connection on the main hemodynamic quantities, both at rest and during exercise, when compared with normal biventricular circulation. The analysis was performed by means of a mathematical model of the cardiovascular system. The model incorporates the main parameters of systemic and pulmonary circulation, the pulsat...

THE alleged occurrence of tricuspid regurgitation in association with, and as a physiologic consequence of, right ventricular failure in cases of cor pulmonale has been reported during the past decade. -3 Emphasis has been laid upon hepatic pulsations, distended or pulsating neck veins, and a systolic murmur of appropriate timing and placement as evidence of this phenomenon. It has been suggest...

Sir, It is accepted that left recurrent laryngeal nerve paralysis in association with massive dilatation of the left atrium is caused by compression between the aortic arch and pulmonary artery by upward displacement of the latter. The cause of dysphagia in these circumstances is less clear. Morgan and Mourant' suggest that it is the result of disordered peristalsis consequent upon stretching o...

Transcranial cerebral sonography (TCCS) is a noninvasive technique that allows the clinician to detect abnormal intracranial-inner-ear fluid interactions in terms of nanoliter tympanic membrane displacements. The displacements recorded in TCCS are evoked either by the acoustic stapedius reflex or spontaneous movements generated by intracranial cardiovascular or by respiratory pressure waves tra...

CASES of pulsating exophthalmos, which are seen from time to time, are mostly vascular in origin. Rarely they are due to transmitted cerebral pulsations, as in congenital failure of the orbital roof, erosion of the walls due to inflammatory processes, and traumatic hiatus of the orbital roof. Occasionally they are due to plexiform neurofibromatosis. von Recklinghausen (1882) first described a c...