A Previously Undiagnosed Case of Alkaptonuria in an 80-Year-Old Patient: A Case Report.

Alkaptonuria is a rare genetic metabolic disorder of autosomal recessive inheritance characterised by the accumulation of homogentisic acid in the body. It is diagnosed upon identification of characteristic symptoms, using various biochemical investigations, radiographic pictures, and a variety of specialised tests. Here we are discussing the case of an 80-year-old female patient with incidental findings of alkaptonuria. It is crucial to understand the fundamental diagnostic investigations that can be used in low-income nations or facilities where investigations like genetic testing, gas chromatography, and mass spectrometry are not readily available for the diagnosis of alkaptonuria.

Experimental validation of a building block of passive devices and stochastic analysis of PICs based on SiOC technology.

Silicon oxycarbide (SiOC) with a wide tunable refractive index window and low absorption coefficient has emerged as an appealing material platform in integrated photonics. Its physical, optical and chemical properties can be tailored over a large window through changes in composition. The circuit simulation based on the building-block approach is a useful framework for deep exploitation of the potential of photonics in the large-scale integration of complex circuits. In this manuscript, the simulation and experimental results of the waveguide and directional coupler based on SiOC technology have been investigated. A simplified model for the coupling coefficient, within defined limits of width, coupling length and gap, of parallel waveguides of the directional coupler has been proposed and validated experimentally. The building blocks of the waveguide and directional coupler have been prepared and parametrized. The proposed models of these passive devices have been exploited in commercially available circuit simulator for the circuit and stochastic simulations of SiOC based photonic circuits.