The microtubes are important structures in nano electromechanical system .in this study a nonlocal model is presented to investigate the static torsion behavior of microtubes made of bi-directional factionally graded material (BDFGM) subjected to a longitudinal magnetic field. Mechanical properties of BDFGM microtube varies in the radial and longitudinal direction according to an arbitrary func...

INTRODUCTION: Mechanical analogue composite bone models have been used as cadaveric bone substitutes in a wide variety of biomechanical tests. The objective of this study was to validate the diaphyseal structural properties in terms of flexural rigidity, ultimate bending strength, axial stiffness, ultimate compression strength, ultimate torsional strength, torque angle at ultimate torsional str...

The evolution of granular shear flow is investigated as a function of height in a split-bottom Couette cell. Using particle tracking, magnetic-resonance imaging, and large-scale simulations, we find a transition in the nature of the shear as a characteristic height H* is exceeded. Below H* there is a central stationary core; above H* we observe the onset of additional axial shear associated wit...

The clinical recognition of constrictive pericarditis (CP) is important but challenging. In addition to Doppler echocardiography, newer echocardiographic techniques for deciphering myocardial deformation have facilitated the noninvasive recognition of CP and its differentiation from restrictive cardiomyopathy. In a patient with heart failure and a normal ejection fraction, echocardiographic dem...

The capacity for short-term adaptation is a well-established property of the horizontal (H) and vertical (V) components of saccades. It allows these directional components, which clearly serve the goal of foveation, to maintain their precision even under changing circumstances. Torsional (T) saccade components, on the other hand, which deal with the orientation of the target on the fovea, have ...

PURPOSE To compare torsional versus combined torsional and conventional ultrasound modes in hard cataract surgery regarding ultrasound energy and time and effect on corneal endothelium. SETTINGS Kasr El Aini hospital, Cairo University, and International Eye Hospital, Cairo, Egypt. METHODOLOGY Ninety-eight eyes of 63 patients were enrolled in this prospective comparative randomized masked cl...

PURPOSE Exotropia in congenital homonymous hemianopia has been reported to provide field expansion that is more useful when accompanied with harmonious anomalous retinal correspondence (HARC). Torsional strabismus with HARC provides a similar functional advantage. In a subject with hemianopia demonstrating a field expansion consistent with torsion, we documented torsional strabismus and torsion...

PURPOSE To analyze temperature increases and identify potential sources of heat generated when sleeved and sleeveless phacoemulsification probes were operated in axial and torsional modes using the Infiniti Vision System with the Ozil torsional handpiece. SETTING Phacodynamics Laboratory, Pasteur Ophthalmic Clinic, Santiago, Chile. DESIGN Experimental study. METHODS Two computer-controlle...

I would like to present our experiences with torsional and micro-coaxial technology on behalf of our French research group. My goal is to demonstrate to surgeons the transition from performing phacoemulsification with traditional longitudinal ultrasound to a micro-coaxial procedure using torsional technology. The impetus for the development of micro-incisional phacoemulsification was to provide...

Torsional harmonic cantilevers allow measurement of time-varying tip-sample forces in tapping-mode atomic force microscopy. Accuracy of these force measurements is important for quantitative nanomechanical measurements. Here we demonstrate a method to convert the torsional deflection signals into a calibrated force wave form with the use of nonlinear dynamical response of the tapping cantilever...