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In this paper, the spectral-domain approach has been used as an efficient method to investigate the dispersive properties of anisotropic multilayered microwave circuits with arbitrary polarization of the optical axis. The analysis is based on Galerkin's method via an adequate choice of basis functions while the spectral dyadic Green's functions have been derived via a recursive algorithm. The proposed approach was demonstrated through successful comparison with data available in the literature.

An improved FDTD hybrid-mode technique is proposed to analyze shielded high-temperature T c superconducting (HTS) microstrip resonators of arbitrary thickness. The temperature dependence on resonant frequency and bandwidth are investigated assuming an anisotropic dielectric substrate. Variations of resonant frequency with high-T c superconducting thickness and shielding effect are also presented as well as S parameters over wideband.

A computationally efficient full-wave technique is presented to analyze the anisotropic high-T c superconducting passive microwave circuits on lossy anisotropic layers in multilayer configuration. The numerical analysis was carried out by the spectral domain approach using a dyadic Green's functions. Simulated complex propagation constant and quality factor parameters have been successfully compared to both published measured and theoretical results.

Purpose Diabetic fibrovascular membranes are the main pathological changes of proliferative diabetic retinopathy that can cause serious complications leading to blindness. Since the mechanism of fibrovascular membrane development is still unknown, the aim of our study was to identify potential biomarkers for this pathology. To this end, we analyzed the simultaneous expression of ICAM-1, VCAM-1 and VEGF within tissues of diabetic fibrovascular membranes. Patients and methods Fibrovascular membranes were taken from nine diabetic patients with proliferative diabetic retinopathy. The fibrovascular membrane specimens were analyzed by immunohistochemistry to determine ICAM-1, VCAM-1 and VEGF expression. Controls were collected on nine normal conjunctivas removed during senile cataract surgery. Results Coexpression of ICAM-1, VCAM-1 and VEGF was found in most of the diabetic fibrovascular membranes studied. Thus, ICAM-1 was positive in eight of nine membranes (82%), VCAM-1 in seven of nine membranes (78%) and VEGF in all the membranes. Conclusions The substantial overexpression of adhesion molecules ICAM-1, VCAM-1 and of VEGF suggests that these molecules might contribute to the development of fibrovascular membranes in patients with proliferative diabetic retinopathy, and that they could constitute suitable markers of this pathology.

The expression pattern of VEGF, p53 and ICAM-1 was studied in conjunctiva of diabetic patients with and without retinopathy. All patients underwent a complete ophthalmic examination, including retinal fluorescein angiography. Indirect immunoperoxidase method was performed on 20 eyes of 20 patients with type II diabetes without DR and on 5 eyes of 5 patients with PDR. A control study was performed on 6 normal conjunctiva undertaken during cataract surgery. Immunoreactivity of VEGF, p53 and ICAM-1 was found in epithelial, fibroblast and vascular endothelial cells. For the same duration of diabetes, a strong to moderate or weak immunoreactivity was observed in the conjunctiva of patients without retinopathy. In patients with PDR, the expression was strong for all these proteins. The immunoreactivity was correlated between VEGF, p53 and ICAM-1. In the normal conjunctiva, a weak to negative immunostaining was observed. The presence of these proteins in the conjunctiva of diabetic patients without retinopathy may add new data in the pathogenesis of diabetic retinopathy. Further studies are needed to confirm this hypothesis.