Information-theoretic aspects of the generalized amplitude damping channel

The generalized amplitude damping channel (GADC) is one of the sources of noise in superconducting-circuit-based quantum computing. It can be viewed as the qubit analogue of the bosonic thermal channel, and it thus can be used to model lossy processes in the presence of background noise for low-temperature systems. In this work, we provide an information-theoretic study of the GADC. We first determine the parameter range for which the GADC is entanglement breaking and the range for which it is anti-degradable. We then establish several upper bounds on its classical, quantum, and private capacities. These bounds are based on data-processing inequalities and the uniform continuity of information-theoretic quantities, as well as other techniques. Our upper bounds on the quantum capacity of the GADC are tighter than the known upper bound reported recently in [Rosati et al., Nat. Commun. 9, 4339 (2018)] for the entire parameter range of the GADC, thus reducing the gap between the lower and upper bounds. We also establish upper bounds on the two-way assisted quantum and private capacities of the GADC. These bounds are based on the squashed entanglement, and they are established by constructing particular squashing channels. We compare these bounds with the max-Rains information bound, the mutual information bound, and another bound based on approximate covariance. For all capacities considered, we find that a large variety of techniques are useful in establishing bounds.Comment: 33 pages, 9 figures; close to the published versio

A single-server Markovian queuing system with discouraged arrivals and retention of reneged customers

Customer impatience has a very negative impact on the queuing system under investigation. If we talk from business point of view, the firms lose their potential customers due to customer impatience, which affects their business as a whole. If the firms employ certain customer retention strategies, then there are chances that a certain fraction of impatient customers can be retained in the queuing system. A reneged customer may be convinced to stay in the queuing system for his further service with some probability, say q and he may abandon the queue without receiving the service with a probability p(=1− q). A finite waiting space Markovian single-server queuing model with discouraged arrivals, reneging and retention of reneged customers is studied. The steady state solution of the model is derived iteratively. The measures of effectiveness of the queuing model are also obtained. Some important queuing models are derived as special cases of this model

Thrombotic Risk Assessment in End Stage Renal Disease Patients on Renal Replacement Therapy

End stage renal disease (ESRD) patients have an excess cardiovascular risk, above that predicted by traditional risk factor models. Despite the advances in both Cardiovascular disease (CVD) management and renal replacement therapy (RRT), there still is a major burden of cardiovascular mortality and morbidity in the chronic kidney disease (CKD) population. Declining renal function itself represents a continuum of cardiovascular risk and in those individuals who survive to reach ESRD, the risk of suffering a cardiac event is uncomfortably and unacceptably high. Pro-thrombotic status may contribute to this increased risk. Global thrombotic status assessment, including measurement of occlusion time (OT) the time taken to form an occlusive platelet rich thrombus and thrombolytic status (time taken to lyse such thrombus) as assessed by measuring Lysis Time (LT), may identify vulnerable patients. The aim of this study was to assess overall thrombotic status in ESRD and relate this to cardiovascular and peripheral thrombotic risk. Small sub studies were also planned to establish the effect of RRT modality on the thrombotic status

Noise resilience of variational quantum compiling

Variational hybrid quantum-classical algorithms (VHQCAs) are near-term algorithms that leverage classical optimization to minimize a cost function, which is efficiently evaluated on a quantum computer. Recently VHQCAs have been proposed for quantum compiling, where a target unitary U is compiled into a short-depth gate sequence V. In this work, we report on a surprising form of noise resilience for these algorithms. Namely, we find one often learns the correct gate sequence V (i.e. the correct variational parameters) despite various sources of incoherent noise acting during the cost-evaluation circuit. Our main results are rigorous theorems stating that the optimal variational parameters are unaffected by a broad class of noise models, such as measurement noise, gate noise, and Pauli channel noise. Furthermore, our numerical implementations on IBM\u27s noisy simulator demonstrate resilience when compiling the quantum Fourier transform, Toffoli gate, and W-state preparation. Hence, variational quantum compiling, due to its robustness, could be practically useful for noisy intermediate-scale quantum devices. Finally, we speculate that this noise resilience may be a general phenomenon that applies to other VHQCAs such as the variational quantum eigensolver

PROCESS VALIDATION IN PHARMACEUTICAL INDUSTRY; AN OVERVIEW

Quality cannot be adequately assured by in-process and finished inspections and testing but it should be built in to the manufacturing process. These processes should be controlled in order that the finished product meets all quality specifications Validation is one of the important steps in achieving and maintaining the quality of the final product. If each step of production process is validated we can assure that the final product is of the best quality. Validation of the individual steps of the processes is called the process validation. Different dosage forms have different validation protocols. Quality is always an imperative prerequisite when we consider any product. Therefore, drugs must be manufactured to the highest quality levels. Process Validation is one of the important steps in achieving and maintaining the quality of final product. It gives a higher degree of assurance. KEY WORDS: Process validation, CGMP, GMP, Validaton protocol , SO

Bilateral post traumatic thalamic infarct: Rare case report

Bilateral thalamic infarction is rarely seen in cases with artery of Percheron embolization. Artery of Percheron is a rare variant of arterial supply to both thalamus and midbrain. Occlusion of this artery following trauma and causing bilateral thalamic infarction is rare and very few cases are reported in world literature

Using the new ICD-MM classification system for attribution of cause of maternal death: a retrospective study from a tertiary care hospital of Rajasthan

Background: Sustainable development goal 3 includes an ambitious target of reducing the global maternal mortality rate (MMR) to less than 70 per 100,000 births by 2030. Understanding the causes of and factors contributing to maternal deaths is critically important for development of interventions that reduce the global burden of maternal mortality and morbidity. The International classification of diseases-maternal mortality has proven to be easily applicable and helps clarify the cause of maternal death. Methods: Retrospective study of 100 maternal death cases was done in a tertiary medical centre of Rajasthan from December 2020 to November 2021 for determining the causes of maternal death and their classification according to ICD-MM. Results: A total of 100 maternal mortality cases were analyzed in this study for causes of death. Classification of causes of death according to WHO ICD-MM is represented in study results. Direct causes of maternal deaths were observed in 82 % cases whereas indirect causes were present in remaining 18%. Hypertensive disorders (29%), obstetric haemorrhage (27%) and pregnancy related infection (12%) constituted the major groups of direct cause of maternal deaths whereas systemic infections were the most common indirect cause (15%). During the study period, COVID-19 was attributable to 12 cases of maternal death.Conclusions: Hypertensive disorders (29%), obstetric haemorrhage (27%) and pregnancy related infection (12%) were the major causes of direct obstetric death and systemic infections (15%) was the most common cause of indirect obstetric death. All of these causes are preventable with targeted interventions