AIMS 2D speckle tracking echocardiography allows for assessment of left ventricular (LV) torsional deformation as a composite function of the radial, longitudinal and circumferential fibres. We test the hypothesis that post-exercise LV torsional dynamics are more sensitive markers for myocardial dysfunction than resting measures, and better predictors for exercise capacity compared to post-exer...

AIMS Visual and microscopic evaluation of defects caused by torsional fatigue in hand and rotary nickel titanium (NiTi) instruments. MATERIALS AND METHODS Ninety-six NiTi greater taper instruments which were routinely used for root canal treatment only in anterior teeth were selected for the study. The files taken include ProTaper for hand use, ProTaper Rotary files and Endowave rotary files....

The purpose of this study was to compare fracture resistances of K3 nickel-titanium files made from different thermal treatments. K3 (SybronEndo, Orange, CA), K3XF (SybronEndo), and experimentally heat treated K3 (K3H) were used. For the cyclic fatigue test, the samples were rotated with up-and-down motion in the artificial canal with the curvature of 60 degrees until the fracture occurred. The...

This work describes the design, implementation and first results of a fatigue test rig capable of subjecting cylindrical specimens of different sizes and materials to complex real-life loading conditions. The resulting test rig can be used to combine a rotating bending load with a fluctuating torsional load. Due to a closed electromechanical loop, power consumption is limited and a maximum test...

PURPOSE To compare a modified phacoemulsification tip with the established micro tip, in terms of temperature at the corneal wound, efficiency, and chatter events, using the Centurion® Vision system. METHODS Eighty porcine eyes were randomized into 4 groups: 1)sleeveless conventional 45D MiniFlared ABS® Kelman tip (1.1-mm incision); 2)sleeveless new modified 45D ABS® INTREPID® balanced tip(1....

Bowing a string with a non-zero radius exerts a torque, which excites torsional waves. In general, torsional standing waves have higher fundamental frequencies than do transverse standing waves, and there is generally no harmonic relationship between them. Although torsional waves have little direct acoustic effect, the motion of the bow-string contact depends on the sum of the transverse speed...

Due to lack of theory of elasticity, estimation of ultimate torsional strength of reinforcement concrete beams is a difficult task. Therefore, the finite element methods could be applied for determination of strength of concrete beams. Furthermore, for complicated, highly nonlinear and ambiguous status, artificial neural networks are appropriate tools for prediction of behavior of such states. ...

Rapid eye movements include saccades and quick phases of nystagmus and may have components around all three axes of ocular rotation: horizontal, vertical, and torsional. In this study, we recorded horizontal, vertical, and torsional eye movements in normal subjects with their heads upright and stationary. We asked how the eyes are brought back to Listing's plane after they are displaced from it...

Abstract. The semi-active torsional vibration absorber can effectively reduce the of power-train system. In this paper, a new type variable stiffness with magnetorheological elastomer (MRE) as an intelligent controlling element is designed, and modal analysis, frequency-tracking scheme, damping effects have been studied. A transient dynamic simulation utilized to validate rationality mechanical...

We investigated the dynamic properties of the human vestibulo-ocular reflex (VOR) during roll head rotations in three human subjects using the magnetic search coil technique. In the first of two experiments, we quantify the behavior of the ocular motor plant in the torsional plane. The subject's eye was mechanically displaced into intorsion, extorsion or abduction, and the dynamic course of ret...