STUDY DESIGN Collagen fiber orientation analysis in moderately degenerated human cadaveric annulus fibrosus (AF) tissue samples. OBJECTIVE Little is known about the changes in tissue architecture during early degeneration of intervertebral disks (IVDs). As collagen organization strongly affects the disk function, the objective of this study was to quantify the AF collagen orientation and its ...

A simple formula was recently proposed by Williams @J. Acoust. Soc. Am. 99, 2022–2032 ~1996!# for imaging pressure and velocity on a vibrating circular cylindrical shell using the far-field pressure measured along a meridional semicircle. The method is examined and some new results are obtained. The procedure is generalized to handle cylindrical surfaces of noncircular but convex cross section....

The continuous and synchronous calibration process for straightness roundness of LSAW (longitudinally submerged arc welding, LSAW) pipes with three rollers is a bidirectional reciprocating bending process. It includes both axial circumferential directions. particularly important to reveal the deformation mechanism, which provides theoretical support be applied actual production. Based on this, ...

the effect of axial deformation of shell particles on the dynamic instability (flutter) of cantilevered cylindrical shells made of functionally graded materials (fgm) under an end axial follower force is addressed. to this end, at first, results for free vibration of fgm cylindrical shells were verified with previous outcomes and they were in very good agreement. then, the effect of axial defor...

BACKGROUND Echocardiographic evaluation of left ventricular (LV) strain and strain rate (SR) by 2D speckle tracking may be useful tools to assess chronic thromboembolic pulmonary hypertension (CTEPH) severity as well as response to successful pulmonary thromboendarterectomy (PTE). METHODS We evaluated 30 patients with CTEPH before and after PTE using 2D speckle tracking measurements of LV rad...

purpose: to report bilateral terrien’s marginal degeneration, circumferential peripheral corneal ectasia and posterior polymorphous dystrophy in a patient with rheumatoid arthritis. case report: a 24-year-old male patient, who was known case of rheumatoid arthritis from 8 years before, presented with decreased vision since four years ago. comprehensive ophthalmic eye exami-nation revealed bilat...

In this paper, the free vibration characteristics of various coupled composite laminated doubly curved revolution shells are investigated under generalized boundary conditions (BCs). The joint shell structure consists a shell–cylindrical shell–doubly structure, and here, unlike previous structures, inversely joined together. such as elliptical, paraboloidal, spherical considered. first order sh...

Circumferential bands of microtubules (MT) support the discoid shape of resting platelets and participate with the contractile apparatus in shape change and internal contraction following activation. Elucidation of interactions between the circumferential coils and proteins of the stable and contractile cytoskeleton is essential for understanding MT function in platelet physiology. A previous i...

Distortion and deformation of tubes during machining operations are very important. In this study, a tube used in magnetic drum separator under concentrated load (machining load) is considered. Using finite element simulation, deformities and their dependence on parameters such as the thickness of the tube and the place of concentrated force are observed and predicted. To compare and confirm th...

In this paper dynamic analysis of multi-directional functionally graded panel is studied using a semi-analytical numerical method entitled the state-space based differential method (SSDQM) and comparative behavior modeling by artificial neural network (ANN) for different parameters. A semi-analytical approach which makes use the three-dimensional elastic theory and assuming the material propert...