The Influence of Activation Time on Contraction Force of Myocardial Tissue: a Simulation Study

2006 ◽  
Author(s):  
Jianyin Lu ◽  
Toshifumi Nishi ◽  
Takashi Ashihara ◽  
Natalie S. Schneider ◽  
Akira Amano ◽  
...  
Keyword(s):  
Simulation Study ◽  
Myocardial Tissue ◽  
Activation Time ◽  
Contraction Force

Effects of acute ischemia on the restitution curves of myocardial tissue: a simulation study

2005 ◽  
Author(s):  
L. Romero ◽  
J.M. Ferrero ◽  
J. Saiz ◽  
B. Trenor ◽  
M. Monserrat ◽  
...  
Keyword(s):  
Simulation Study ◽  
Acute Ischemia ◽  
Myocardial Tissue

Activation time while using stand-alone feedback devices during cardiopulmonary resuscitation: A randomised simulation study

Resuscitation ◽  
2013 ◽  
Vol 84 ◽  
pp. S19
Author(s):  
Florian Schachinger ◽  
Julian Voittl ◽  
Paul Bsuchner ◽  
Dominik Stumpf ◽  
Bernhard Zapletal ◽  
...  
Keyword(s):  
Cardiopulmonary Resuscitation ◽  
Simulation Study ◽  
Activation Time

An Insight into the Importance of Wrist Torque in Driving the Golfball: A Simulation Study

2000 ◽  
Vol 16 (4) ◽  
pp. 356-366 ◽  
Author(s):  
Eric J. Sprigings ◽  
Robert J. Neal
Keyword(s):  
Simulation Study ◽  
Shoulder Joint ◽  
Wrist Joint ◽  
Optimal Timing ◽  
Horizontal Line ◽  
Activation Time ◽  
Sequential Order ◽  
Segment Model ◽  
Force Velocity ◽  
Insight Into

The purpose of this study was to examine whether, in theory, the clubhead speed at impact could be increased by an optimally timed wrist torque, without jeopardizing the desired club position at impact. A 2-D, three-segment model comprising torso, left arm, and golfclub was used to model the downward phase of the golf swing. Torque generators that adhered to the activation and force-velocity properties of muscle were inserted at the proximal end of each segment. Separate simulations were performed, with the wrist joint generator enabled then disabled. The results from these simulations showed that significant gains in clubhead speed (≈9 %) could be achieved if an active wrist torque was applied to the club during the latter stages of the downswing. For a swing that produced a clubhead speed of 44 m/s (≈99 mph), the optimal timing for the activation of wrist torque occurred when the arm segment was approximately 30° below a horizontal line through the shoulder joint. The optimal activation time for the joint generators was very much dependant on the shape of the torque profiles. The optimization process confirmed that maximum clubhead speed was achieved when the torque generators commenced in sequential order from proximal to distal.

scholarly journals Visualization of Myocardial Strain Pattern Uniqueness with Respect to Activation Time and Contractility: A Computational Study

Data ◽  
2019 ◽  
Vol 4 (2) ◽  
pp. 79
Author(s):  
Borut Kirn
Keyword(s):  
Parameter Space ◽  
Measurement Errors ◽  
Computational Study ◽  
Myocardial Strain ◽  
Myocardial Tissue ◽  
Connected Component ◽  
Activation Time ◽  
Mechanical Coupling ◽  
Strain Pattern ◽  
High Uncertainty

Speckle tracking echography is used to measure myocardial strain patterns in order to assess the state of myocardial tissue. Because electro-mechanical coupling in myocardial tissue is complex and nonlinear, and because of the measurement errors the uniqueness of strain patterns is questionable. In this study, the uniqueness of strain patterns was visualized in order to revel characteristics that may improve their interpretation. A computational model of sarcomere mechanics was used to generate a database of 1681 strain patterns, each simulated with a different set of sarcomere parameters: time of activation (TA) and contractility (Con). TA and Con ranged from −100 ms to 100 ms and 2% to 202% in 41 steps respectively, thus forming a two-dimensional 41 × 41 parameter space. Uniqueness of the strain pattern was assessed by using a cohort of similar strain patterns defined by a measurement error. The cohort members were then visualized in the parameter space. Each cohort formed one connected component (or blob) in the parameter space; however, large differences in the shape, size, and eccentricity of the blobs were found for different regions in the parameter space. The blobs were elongated along the TA direction (±50 ms) when contractility was low, and along the Con direction (±50%) when contractility was high. The uniqueness of the strain patterns can be assessed and visualized in the parameter space. The strain patterns in the studied database are not degenerated because a cohort of similar strain patterns forms only one connected blob in the parameter space. However, the elongation of the blobs means that estimations of TA when contractility is low and of Con when contractility is high have high uncertainty.

scholarly journals Influence of Activation Time on Hemodynamic Parameters: a Simulation Study

2016 ◽  
Vol 5 (0) ◽  
pp. 94-104
Author(s):  
Kosuke Taniguchi ◽  
Hiromasa Utaki ◽  
Daichi Yamamoto ◽  
Yukiko Himeno ◽  
Akira Amano
Keyword(s):  
Simulation Study ◽  
Hemodynamic Parameters ◽  
Activation Time
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