A new UTD formulation for multiple cylindrical diffraction
This paper describes a new formulation of the uniform theory of diffraction (UTD) with application to multiple cylindrical structures. The new formulas present some modified UTD diffraction coefficients in cooperation with a slope diffraction term for higher accuracy in the electromagnetic modeling. The above are then combined with a simple ray tracing algorithm that takes into account multipath propagation between cylindrical structures. Comparisons with existing analytical models that employ other electromagnetic theories have shown that the new UTD solution can give very accurate results while it seems to be superior in terms of computation time and complexity. The solution can be applicable to radiowave paths which are characterized by convex structures and multipath propagation such as mountainous areas or urban areas with special rounded objects
An improved heuristic UTD solution for multiple-edge transition zone diffraction
This paper describes a new heuristic approach for multiple edge diffraction modeling based on the uniform theory of diffraction (UTD). It incorporates the slope diffraction terms which can be realized as a second-order diffraction process, vital for accurate predictions when more than one edge exists. The predictions of this approach are compared with the Vogler (1982) solution and were found to be in very good agreement for many different geometrical arrangements, with low computational complexity. The solution is also extended to wedge diffraction.
Use of a specific antiserum for renin detection in human kidney.
The use of anti-human renin antibodies made possible the intrarenal localization of renin in human kidney by immunofluorescence. In normal kidney, only some juxtaglomerular apparatus (JGA) were fluorescent. In these JGA, granular or diffuse fluorescence was only seen in afferent arterioles and was not present in all cells. In the ischemic areas of partially infarcted kidney, fluorescence was seen in all JGA and in interlobular arteries. In these arteries the most eccentric cells were often the most positive. In the nonischemic areas of the same kidneys, fluorescence was not seen in JGA, but was observed in proximal tubular cells, suggesting the reabsorption of filtered renin at this site.