Yoshikawa Hideki

Energy loss functions derived by Monte Carlo simulation from the Au 4f XPS spectrum

Abstract We have used conventional deconvolution methods to obtain the original no-loss XPS spectrum, the so-called source function, by using loss functions derived from optical constant measurements and high-energy electron transmission experiments. However, the source functions derived are far from the Lorentzian type expected theoretically, because these loss functions do not precisely describe the actual energy loss processes of photoelectrons of low energies ranging from 100 eV to 1000 eV, where surface excitations, for example, play an important role. We have, therefore, attempted to derive a more reasonable loss function for Au4f X-ray photoelectrons by Monte Carlo simulation of the escape processes of signal electrons, in which both the elastic and inelastic scattering are included. The result indicates that the present Monte Carlo simulation reproduces the XPS spectrum very well, leading to the derivation of a more realistic loss function of wider practical use.

Three-dimensional morphological analysis of humeral heads: a study in cadavers.

Background Anatomy of the humeral head may be of importance for the kinematics of the shoulder joint. We therefore evaluated the three-dimensional morphology of humeral heads. Material and methods We performed three-dimensional morphological analysis of the articular surfaces of 14 humeral heads in the proximal humeri of 7 cadavers. The articular surface was divided into 9 portions, which were in turn equally divided into 3 sections by an angle in supero-inferior and antero-posterior directions. Each portion of the articular surface was fitted to a sphere, and we calculated the radius of the curvature of each portion. Results The mean radius of the superior portion was significantly greater than that of the central portion, and the mean radii of the anterior and posterior portions were significantly less than that of the central portion. Interpretation Our findings lead us to believe that the morphology of the humeral head is of importance for the kinematics of the shoulder joint.