Dynamic torsion of an orthotropic conical rod

1983 ◽  
Vol 49 (6) ◽  
pp. 178-181
Author(s):  
Michael R. Sitzer
Keyword(s):  
1961 ◽  
Vol 1 (4-6) ◽  
pp. 602-602
Author(s):  
A. F. H. Ward ◽  
G. M. Jenkins
Keyword(s):  

1976 ◽  
Vol 18 (3) ◽  
pp. 149-158 ◽  
Author(s):  
R. D. Adams ◽  
J. Coppendale

A method of measuring the dynamic torsion and Young's moduli of a thin film of adhesive is described. The accuracy of the technique and its suitability for structural adhesives is discussed. Values of modulus obtained using this method are compared with values obtained from static and dynamic tests on bulk specimens of three epoxy adhesives.


1985 ◽  
Vol 17 (6) ◽  
pp. 801-805 ◽  
Author(s):  
A. A. Ostsemin ◽  
V. A. Lupin

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
M D M Perez Gil ◽  
V Mora Llabata ◽  
A Saad ◽  
A Sorribes Alonso ◽  
V Faga ◽  
...  

Abstract BACKGROUND New echocardiographic phenotypes of heart failure (HF) are focused on myocardial systolic involvement of the left ventricle (LV), either endocardial and/or transmural. PURPOSE. To study the pattern of myocardial involvement in patients (p) with HF with preserved left ventricular ejection fraction (pLVEF) and cardiac amyloidosis (CA). METHODS. Comparative study of 16 p with CA and HF with pLVEF, considering as cut point LVEF > 50%, in NYHA class ≥ II / IV, and a control group of 16 healthy people. Longitudinal Strain (LS) and Circumferential Strain (CS) were calculated using 2D speckle-tracking echocardiography, along with Mitral Annulus Plane Systolic Excursion (MAPSE) and Base-Apex distance (B-A). Also, the following indexes were calculated: Twist (apical rotation + basal rotation, º); Classic Torsion (TorC): (twist/B-A, º/cm); Torsion Index (Tor.I): (twist/MAPSE, º/cm) and Deformation Index (Def.I): (twist/LS, º). We suggest the introduction of these dynamic torsion indexes as Tor.I and Def.I that include twist per unit of longitudinal systolic shortening of the LV instead of using TorC which is the normalisation of twist to the end-diastolic longitudinal diameter of the LV. RESULTS There were no differences of age between the groups (68.2 ± 11.5 vs 63.7 ± 2.8 years, p = 0.14). Global values of LS and CS were lower in p with CA indicating endocardial and transmural deterioration during systole, while TorC and Twist of the LV remained conserved in p with CA. However, there is an increase of dynamic torsion parameters such as Tor.I and Def.I that show an increased Twist per unit of longitudinal shortening of the LV in the CA group (Table). CONCLUSIONS In p with CA and HF with pLVEF, the impairment of LS and CS indicates endocardial and transmural systolic dysfunction. In these conditions, LVEF would be preserved at the expense of a greater dynamic torsion of the LV. Table LS (%) CS (%) Twist (º) TorC (º/cm) Tor.I (º/cm) Def.I (º/%) CA pLVEF (n = 16) -11.7 ± 4.2 17.2 ± 4.8 19.8 ± 8.3 2.5 ± 1.1 27.7 ± 13.5 -1.8 ± 0.9 Control Group (n = 15) -20.6 ± 2.5 22.7 ± 4.9 21.7 ± 6.1 2.7 ± 0.8 16.4 ± 4.7 -1.0 ± 0.3 p < 0.001 < 0.01 0.46 0.46 < 0.01 < 0.01 Dynamic Torsion Indexes and Classic Torion Parameters in pLVEF CA patients vs Control group.


2020 ◽  
Vol 46 (2) ◽  
pp. 195-206
Author(s):  
J. Chigvinadze ◽  
S. Ashimov ◽  
A. Dolbin ◽  
G. Mamniashvili

1976 ◽  
Vol 11 (3) ◽  
pp. 408-417
Author(s):  
I. A. Kiiko ◽  
M. Kh. Il'yasov
Keyword(s):  

1988 ◽  
Vol 128 (5) ◽  
pp. 245-250 ◽  
Author(s):  
Peter Baekler ◽  
Metin Gürses ◽  
Friedrich W. Hehl ◽  
J.Dermott McCrea

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