The main goal of this paper is experimental analysis of selected mechanical properties of single annulus fibrosus lamellae at macroscopic and microscopic levels as well as representation and explanation of the structural response to forced deformation. The conducted analysis of single annulus fibrosus lamella with preserved natural attachments revealed two characteristic mechanisms leading to d...

The paper is concerned with the bifurcation of limit cycles in general quadratic perturbations of a quadratic reversible and non-Hamiltonian system, whose period annulus is bounded by an elliptic separatrix related to a singularity at infinity in the Poincaré disk. Attention goes to the number of limit cycles produced by the period annulus under perturbations. By using the appropriate Picard-Fu...

In Euclidean plane, a rectangular annulus is the region between parallel rectangles such that the smaller rectangle lies wholly inside the outer rectangle. Given a set P of n points in the two dimensional plane, we propose O(n) time and O(n) space algorithm to identify an axis-parallel largest empty annulus amidst the points of P . We are not aware of any published work on this problem. To the ...

An annulus is defined as a set of points contained between two circles. This paper presents a method for fitting an annulus to a given set of points in a 2D images in the presence of noise by maximizing the number of inliers, namely the consensus set, while fixing the thickness. We present a deterministic algorithm that searches the optimal solution(s) within a time complexity of O(N), N being ...

We studied 135 lumbar discs from 27 spines removed post-mortem from subjects of an average age of 31.5 years. Defects of the annulus fibrosus were classified as peripheral, circumferential or radiating; the nucleus pulposus as normal, moderately or severely degenerate. Peripheral tears were more frequent in the anterior annulus, except in the L5-S1 disc. Circumferential tears were equally distr...

We study the annulus amplitudes of (p, q) minimal string theory and their geometrical interpretation in terms of the Riemann surface Mp,q that emerges from the FZZT branes. Focusing on the ZZ-FZZT annulus amplitude as a target-space probe of the ZZ brane, we use it to confirm that the ZZ branes are localized in the strong-coupling region. We also show that the deformation to Mp,q due to the pre...

STUDY DESIGN Cultured annulus fibrosus cells within an atelocollagen honeycomb-shaped scaffold with a membrane seal were allografted into the lacunas of intervertebral discs of which the nucleus pulposus had been vaporized using an indocyanine green dye-enhanced laser. Regeneration of the intervertebral disc was assessed based on the viability and histologic status of the allografted annulus fi...

BACKGROUND Mitral annulus is a complex structure of poorly understood physiology. Full-volume real-time 3-dimensional transesophageal echocardiography offers a unique opportunity to completely image and quantify mitral annulus size and motion. METHODS AND RESULTS Real-time 3-dimensional transesophageal echocardiography of the mitral valve was acquired in 32 patients with myxomatous valve dise...