Fault Tolerance in Reversible Logic Circuits and Quantum Cost Optimization

Energy dissipation is a prominent factor for the very large scale integrated circuit (VLSI). The reversible logic-based circuit was capable to compute the logic without energy dissipation. Accordingly, reversible circuits are an emerging domain of research based on the low value of energy dissipation. At nano-level design, the critical factor in the logic computing paradigm is the fault. The proposed methodology of fault coverage is powerful for testability. In this article, we target three factors such as fault tolerance, fault coverage and fault detection in the reversible KMD Gates. Our analysis provides good evidence that the minimum test vector covers the 100 % fault coverage and 50 % fault tolerance in KMD Gate. Further, we show a comparison between the quantum equivalent and controlled V and V+ gate in all the types of KMD Gates. The proposed methodology mentions that after controlled V and V+ gate based ALU, divider and Vedic multiplier have a significant reduction in quantum cost. The comparative results of designs such as Vedic multiplier, division unit and ALU are obtained and they are analyzed showing significant improvement in quantum cost

Effectiveness of the ChAdOx1 nCoV-19 Coronavirus Vaccine (CovishieldTM) in Preventing SARS-CoV2 Infection, Chennai, Tamil Nadu, India, 2021

We estimated the effectiveness of two doses of the ChAdOx1 nCoV-19 (Covishield) vaccine against any COVID-19 infection among individuals ≥45 years in Chennai, Tamil Nadu, India. A community-based cohort study was conducted from May to September 2021 in a selected geographic area in Chennai. The estimated sample size was 10,232. We enrolled 69,435 individuals, of which 21,793 were above 45 years. Two-dose coverage of Covishield in the 18+ and 45+ age group was 18% and 31%, respectively. Genomic analysis of 74 out of the 90 aliquots collected from the 303 COVID-19-positive individuals in the 45+ age group showed delta variants and their sub-lineages. The vaccine’s effectiveness against COVID-19 disease in the ≥45 age group was 61.3% (95% CI: 43.6–73.4) at least 2 weeks after receiving the second dose of Covishield. We demonstrated the effectiveness of two doses of the ChAdOx1 vaccine against the delta variant in the general population of Chennai. We recommend similar future studies considering emerging variants and newer vaccines. Two-dose vaccine coverage could be ensured to protect against COVID-19 infection