The study of amplitude and phase relaxation impact on the quality of quantum information technologies

The influence of amplitude and phase relaxation on evolution of quantum states within the formalism of quantum operations is considered. The model of polarizing qubits where noises are determined by the existence of spectral degree of freedom that shows up during the light propagation inside anisotropic mediums with dispersion is studied. Approximate analytic model for calculation of phase plate impact on polarizing state with dispersion influence taken into consideration is suggested.Comment: 7 pages, 4 figures, report for the International Symposium "Quantum Informatics-2014" (QI-2014), Zvenigorod, Moscow region, October 06-10, 201

Numerical and analytical research of the impact of decoherence on quantum circuits

Three different levels of noisy quantum schemes modeling are considered: vectors, density matrices and Choi-Jamiolkowski related states. The implementations for personal computers and supercomputers are described, and the corresponding results are shown. For the level of density matrices, we present the technique of the fixed rank approximation and show some analytical estimates of the fidelity level.Comment: 11 pages, 9 figures, report for the International Symposium "Quantum Informatics-2014" (QI-2014), Zvenigorod, Moscow region, October 06-10, 201

Diabetes mellitus and long-time outcomes of autovenous femoro-popliteal bypass

BACKGROUND: the effect of diabetes mellitus on the long-term patency of autovenous femoro-popliteal bypass has not been definitively determined AIM: to determine the effect of diabetes mellitus on the long-term outcomes of autovenous femoral-popliteal bypass.MATERIALS AND METHODS: the results of treatment of 648 patients who underwent autovenous femoral-popliteal bypass were analyzed. The patients were divided into 2 clinical groups: the first group included 367 patients with diabetes mellitus, the second — 281 patients without the named disease. The groups did not differ significantly in the incidence of concomitant pathology.RESULTS: occlusion of the autovenous conduit within a 5-year period after surgical treatment was observed in 218 patients of the first group (59.4%) and 72 patients of the second group (25.6%) (p <0.01, χ2 = 39.05, RR = 1.78; CI = 1.53–2.12). The average service life of the autovenous femoral-popliteal bypass was 63.49 months in patients of the first group, and 107.46 months in the second. The decompensated course of diabetes mellitus was observed in 203 patients (55.2%). Among patients with decompensated diabetes mellitus, occlusion of the autovenous femoral-popliteal bypass was observed in 95 patients (46.8%), in 104 patients the autovenous conduit was passable (51.2%; p = 0.449, χ2 = 0.57). Decompensated course of diabetes mellitus may contribute to a decrease in the service life of autovenous femoro-popliteal bypass.CONCLUSION: the presence of diabetes mellitus, and especially its decompensated course, can negatively affect the patency of autovenous femoro-popliteal bypass in the long term

Fast reconstruction of programmable integrated interferometers

Programmable linear optical interferometers are important for classical and quantum information technologies, as well as for building hardware-accelerated artificial neural networks. Recent results showed the possibility of constructing optical interferometers that could implement arbitrary transformations of input fields even in the case of high manufacturing errors. The building of detailed models of such devices drastically increases the efficiency of their practical use. The integral design of interferometers complicates its reconstruction since the internal elements are hard to address. This problem can be approached by using optimization algorithms [Opt. Express 29, 38429 (2021)]. In this paper, we present a novel efficient algorithm based on linear algebra only, which does not use computationally expensive optimization procedures. We show that this approach makes it possible to perform fast and accurate characterization of high-dimensional programmable integrated interferometers. Moreover, the method provides access to the physical characteristics of individual interferometer layers

WRAPPING AROUND THE RECONSTRUCTION PLATE WITH A PECTORALIS MUSCLE FLAP IN MANDIBULAR REPAIR AFTER SEGMENTAL RESECTION

The paper gives information on the proposed procedure for wrapping around the reconstruction plate with a pectoralis muscle flap in case of segmental resection of the lower jaw and recovery of its continuity with a titanium plate if there is a sufficient area of integuments (skin and mucosa) and soft tissue shortage