BACKGROUND Radial head prostheses are available with multiple geometric properties. The effect of design features on radiocapitellar stability has not been investigated. HYPOTHESIS The shape (depth and radius of curvature) of the articulating dish of a radial head prosthesis affects radiocapitellar stability. MATERIALS AND METHODS Radiocapitellar stability due to concavity-compression was e...

To learn about the basic aspects of nanoscale spherical molecular shells during their formation, spherically curved two-dimensional N-particle Lennard-Jones systems are simulated, studying curvature evolution paths at zero temperature. For many N values (N<800) equilibrium configurations are traced as a function of the curvature radius R. Sharp jumps for tiny changes in R between trajectories w...

Let (M, g) be a complete non compact Kähler manifold with non-negative and bounded holomorphic bisectional curvature. Extending our techniques developed in [8], we prove that the universal cover M̃ of M is biholomorphic to Cn provided either that (M, g) has average quadratic curvature decay, or M supports an eternal solution to the Kähler-Ricci flow with non-negative and uniformly bounded holomo...

The gluing technique is used to construct hypersurfaces in Euclidean space having approximately constant prescribed mean curvature. These surfaces are perturbations of unions of finitely many spheres of the same radius assembled end-to-end along a line segment. The condition on the existence of these hypersurfaces is the vanishing of the sum of certain integral moments of the spheres with respe...

In this paper are determined the principal curvatures and principal curvature lines on canal surfaces which are the envelopes of families of spheres with variable radius and centers moving along a closed regular curve in R3. By means of a connection of the differential equations for these curvature lines and real Riccati equations, it is established that canal surfaces have at most two isolated...

OBJECTIVE To describe ocular biometry relationships in older white adults. METHODS Ocular dimensions were measured with partial coherence laser interferometry in 1968 persons (aged 58-100 years, 59% female) seen at the fourth examination of the Beaver Dam Eye Study. Generalized estimating equations-modeled associations of age, sex, height, and education with ocular dimensions: axial length, c...

It is of fundamental interest to study the geometric and analytic properties of compact Einstein manifolds and their moduli. In dimension 2 these problems are well understood. A 2-dimensional Einstein manifold, (M, g), has constant curvature, which after normalization, can be taken to be −1, 0 or 1. Thus, (M, g) is the quotient of a space form and the metric, g, is completely determined by the ...

The aim of this research was to accurately measure the surface of the semi lunar articular surface of the pelvis (facies lunata acetabuli) and the variability of the acetabular geometry, as well as to determine the correlation between measured parameters. 30 macerated anatomical specimens of pelvic bones were measured. The radius and depth were measured in the classical way, while cartilaginous...