Publications by authors named "N B Anikin"

The Doppler-signal processing method based on two integral convolutions with respect to approximate Doppler phase, φ(t), being a variable is introduced. While reducing the noise, these transforms produce the first Doppler harmonic, S (t), and its quadrature complement, S (t). The complex harmonic, s(t)=S (t)+iS (t), makes it possible to find a new approximation of both Doppler signal frequency ω(t) and phase φ(t), as well as the rms frequency error, χ (t), used to regularize the solution.

View Article and Find Full Text PDF

This paper presents a hybrid interferometric system designed to measure the surface velocity of tested specimens in shock-wave experiments. The system integrates the All-Fiber Velocity Interferometer System for Any Reflector (AFVISAR) and the Photonic Doppler Velocimeter (PDV) interferometric channels using a single probing system to measure the velocity of one surface point of specimens under study. This design allows the same optical signal containing the Doppler frequency shift to be processed by the AFVISAR and PDV independent interferometric devices.

View Article and Find Full Text PDF

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare and life-threatening complication of pulmonary embolism. As existing animal models of CTEPH do not fully recapitulate complex disease pathophysiology, we report a new rat model for CTEPH evoked by repetitive embolization of the distal pulmonary artery branches with partially biodegradable alginate microspheres (MSs). MSs (180 ± 28 μm) were intravenously administered eight times at 4-day intervals; control animals received saline.

View Article and Find Full Text PDF

A major translational barrier to the use of stem cell (SC)-based therapy in patients with myocardial infarction (MI) is the lack of a clear understanding of the mechanism(s) underlying the cardioprotective effect of SCs. Numerous paracrine factors from SCs may account for reduction in infarct size, but myocardial salvage associated with transdifferentiation of SCs into vascular cells as well as cardiomyocyte-like cells may be involved too. In this study, bone marrow-derived rat mesenchymal SC (MSCs) were microencapsulated in alginate preventing viable cell release while supporting their secretory phenotype.

View Article and Find Full Text PDF

A linear-scaling semiempirical method, LocalSCF, has been proposed for the quantum-chemical calculations of ultralarge molecular systems by treating the large-scale molecular task as a variational problem. The method resolves the self-consistent field task through the finite atomic expansion of weakly nonorthogonal localized molecular orbitals. The inverse overlap matrix arising from the nonorthogonality of the localized orbitals is approximated by preserving the first-order perturbation term and applying the second-order correction by means of a penalty function.

View Article and Find Full Text PDF