Assessment of biological age by multiple regression analysis

In order to generate a reference value of aging, estimation of chronological age of healthy subjects was made by multiple regression analysis. It was shown that the estimated ages of hypertensive subjects by the formula used were significantly higher than their chronological ages. It was further observed that parameters representing various ability of movements might yield an alternative regression formula and that the accuracy in age estimation was improved with application of a second-order regression formula.

Backscattered short pulse response of surface waves from dielectric spheres

A short pulse response for surface waves involved in the backscattering by dielectric spheres is considered in the time domain. Since the surface-wave contributions for the cw backscattering are known, pulse returns for the surface waves are obtained from the cw solutions by Fourier synthesis. Large savings in computation time for a Fourier series were realized with the use of the fast Fourier transform algorithm. The return positions in the short pulse response can be approximately estimated from a scattering model for surface waves depicted by Van de Hulst. With the propagation constant in the dielectric sphere rather than in free space for a wave traveling along the sphere surface, a better agreement between the predicted and calculated positions for the short pulse returns was obtained. Significant returns of surface waves for the backscattering come from the surface waves that have made the maximum number of shortcuts possible through the sphere.

New calculation of surface wave contributions associated with mie backscattering

Diffracted field contributions to backscattering of an electromagnetic plane wave by a spherical particle are calculated. The diffracted fields give rise to surface waves in the shadow region and can be evaluated by finding surface wave poles and computing their residues. In order to compute the residues the valid range of the Schobe and Debye asymptotic expansion formulas for the Hankel function is examined. With these asymptotic formulas numerical values of the surface wave complex poles are tabulated. Curves for backscattering cross section due to the first six surface waves are presented as a function of the size parameter kappaa between 5 and 60 for absorbing spheres of refractive index m = 1.61-i0.0025 as well as nonabsorbing spheres with m = 1.60.