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Ramy Awad,1 Alaa Atef Ghaith,2 Khaled Awad,1 Marina Mamdouh Saad,1 Ahmed Ak Elmassry2 1Department of Ophthalmology, Alexandria General Ophthalmology Hospital, Alexandria, Egypt; 2Department of Ophthalmology, Faculty of Medicine, Alexandria University, Alexandria, EgyptCorrespondence: Ahmed Ak Elmassry, Ophthalmology Department, Faculty of Medicine, Alexandria University, Champollion Street, Al Attarin, Alexandria, Egypt, Tel +2 0122 215 2435, Email ahmad.elmassry@gmail.comAbstract: Fungal keratitis is one of the major causes of microbial keratitis that may lead to corneal blindness. Many problems related to diagnosis and therapy are encountered in fungal keratitis, including difficulty in obtaining laboratory diagnoses and the availability and efficacy of antifungal medications. Intensive and prolonged use of antifungal topical preparations may not be enough. The use of antifungal medications is considered the main treatment for fungal keratitis. It is recommended to start antifungal therapy after confirmation of the clinical diagnosis with a smear or positive cultures. Topical application of antifungal medications is a mainstay for the treatment of fungal keratitis; however, systemic, intra-stromal, or intra-cameral routes may be used. Therapeutic keratoplasty is the main surgical procedure approved for the management of fungal keratitis with good success rate. Intrastromal corneal injection of antifungal medications may result in steady-state drug levels within the corneal tissue and prevent intervals of decreased antifungal drug concentration below its therapeutic level. In cases of severe fungal keratitis with deep stromal infiltration not responding to treatment, intracameral injection of antifungal agents may be effective. Collagen cross-linking has been proposed to be beneficial for cases of fungal keratitis as a stand-alone therapy or as an adjunct to antifungal medications. Although collagen cross-linking has been extensively studied in the past few years

Modern digital communication systems target satisfying multiple standards and different operating scenarios. Applications include read channels of data storage systems, PCIe links, FPGA I/Os, and multi-standard radios. This stimulates the research on reconfigurable analog-to-digital converters (ADCs) to serve as a key building block at the front-end of such systems. Conventional reconfigurable designs suffer from poor figure-of-merit (FoM) scaling with different resolutions, which reduces their flexibility. The limited efficiency of these techniques is attributed to the fact that they fix the ADC architecture for all configurations, whereas the optimum architecture depends on the target resolution. This dissertation introduces an architecture reconfigurable ADC that efficiently covers a wide range of resolutions by configuring the ADC to the proper architecture for each resolution. This leads to a reconfigurable ADC nearly as efficient as dedicated designs in both area and power. Device matching is the heart of precision analog design. Basically, well matched devices come at the expense of larger die, parasitic capacitance and power consumption. Instead of only sizing the devices to achieve the desired accuracy, the intrinsic accuracy of an area efficient converter is designed worse than its resolution. Before or during chip usage, self-calibration automatically detects and corrects for elements mismatches and leads to reduced silicon area and improved yield. This dissertation investigates the efficiency of using body voltage trimming calibration for data converters. The tradeoffs of this technique are studied in details. Suggested methods have been presented to extend the use of bulk voltage trimming beyond technology limitations with minimal area and power overhead and no special technology requirements. The study shows that best results are achieved when mixing bulk trimming with other calibration techniques.Two prototype chips are implemented in 65-nm CMOS to ve

Modern digital communication systems target satisfying multiple standards and different operating scenarios. Applications include read channels of data storage systems, PCIe links, FPGA I/Os, and multi-standard radios. This stimulates the research on reconfigurable analog-to-digital converters (ADCs) to serve as a key building block at the front-end of such systems. Conventional reconfigurable designs suffer from poor figure-of-merit (FoM) scaling with different resolutions, which reduces their flexibility. The limited efficiency of these techniques is attributed to the fact that they fix the ADC architecture for all configurations, whereas the optimum architecture depends on the target resolution. This dissertation introduces an architecture reconfigurable ADC that efficiently covers a wide range of resolutions by configuring the ADC to the proper architecture for each resolution. This leads to a reconfigurable ADC nearly as efficient as dedicated designs in both area and power. Device matching is the heart of precision analog design. Basically, well matched devices come at the expense of larger die, parasitic capacitance and power consumption. Instead of only sizing the devices to achieve the desired accuracy, the intrinsic accuracy of an area efficient converter is designed worse than its resolution. Before or during chip usage, self-calibration automatically detects and corrects for elements mismatches and leads to reduced silicon area and improved yield. This dissertation investigates the efficiency of using body voltage trimming calibration for data converters. The tradeoffs of this technique are studied in details. Suggested methods have been presented to extend the use of bulk voltage trimming beyond technology limitations with minimal area and power overhead and no special technology requirements. The study shows that best results are achieved when mixing bulk trimming with other calibration techniques.Two prototype chips are implemented in 65-nm CMOS to ve