Biomedical subjects

A Cucinotta

Publications and source records attributed to A Cucinotta.

3 recordsLinked to original sources

PubMed2005

Single-mode regime of square-lattice photonic crystal fibers.

The modal cutoff of square-lattice photonic crystal fibers with a finite number of air-hole rings has been accurately investigated to our knowledge for the first time. By analyzing the leaky behavior of the second-order mode, we have obtained a phase diagram that describes the regions of single-mode and multimode operation as well as the endlessly single-mode regime. Furthermore, starting from these results, we have obtained the cutoff normalized frequency according to two different formulations of the V parameter previously adopted for fibers with a triangular lattice. A final comparison of the cutoff properties of fibers characterized by a square lattice and a triangular lattice has been carried out.

Journal Article↗

PubMed2000

Three-dimensional finite-element beam propagation method: assessments and developments

In recent years the finite-element method (FEM) has been widely applied to three-dimensional beam propagation analysis, and several FEM propagators have been presented. Up to now, as far as we know, an exhaustive, deep, and comparative analysis of these formulations and of the related algorithms has never been presented. We critically analyze and numerically compare, to our knowledge for the first time, different vectorial, semivectorial, and scalar formulations in order to check their performances, point out weaknesses, and suggest future developments. The results obtained highlight once more the inadequacy of scalar approaches in dealing with actual photonics devices and suggest vector formulations worthy of further development and future research.

Journal Article↗

PubMed1991

Histochemistry and electron-microscopic observation in two cases of granular dystrophy of the cornea.

We report on 2 cases of granular dystrophy (Groenouw type I). We studied the nature and the ultrastructure of the typical stromal deposits by means of histochemical methods and of electron-microscopic examination. These deposits did not stain with Alcian blue, periodic acid-Schiff, Mallory, van Gieson, von Kossa or Congo red so that they are not constituted of proteoglycans, collagen, calcium or amyloid. They probably contain a proteic material. At the electron-microscopic level we observed electron-dense material which was made up of filaments immersed into an amorphous matrix.

Adult↗