Design of non-linear filter in the problem of structural identification of biomedical signals with locally concentrated properties

In this paper we propose a generalized method of structural identification of biomedical signals with locally concentrated properties using a digital non-linear filter. The experimental verification of the detecting function was performed by using different ways to describe the model of the desired class of structural elements

Development of method of matched morphological filtering of biomedical signals and images

Formalized approach to the analysis of biomedical signals and images with locally concentrated features is developed on the basis of matched morphological filtering taking into account the useful signal models that allowed generalizing the existing methods of digital processing and analysis of biomedical signals and images with locally concentrated features. The proposed matched morphological filter has been adapted to solve such problems as localization of the searched structural elements on biomedical signals with locally concentrated features, estimation of the irregular background aimed at the visualization quality improving of biological objects on X-ray biomedical images, pathologic structures selection on mammogram. The efficiency of the proposed methods of matched morphological filtration of biomedical signals and images with locally concentrated features is proved by experiments

36 Months Survivability And Its Predictors In Patients With Chronic Heart Failure And Decreased Fraction Of Left Ventricular Ejection Depending On Sex

Aim of the work: to compare survivability parameters during 36 months and their predictors among men and women with chronic heart failure and decreased fraction of left ventricular ejection.Materials and methods: the research included 356 patients with CHF (NYHA ІІ –ІV) with decreased LVEF<40 %, 18–75 years old. Using Kaplan-Meier method, there was analyzed the survivability in men and women during 36 months, then there were analyzed independent factors that influenced survivability terms depending on sex using the multiple logistic regression.Results. Our analysis of the survivability of patients with CHF with decreased LVEF demonstrated that the cumulative survival after 3 years of observation was 49 and 51 % for men and women, respectively. The curves of 36 months survivability didn\u27t reliably differ. At the analysis of factors, associated with the bad prognosis, there were observed differences between groups of men and women with CHF. Thus, in men the predictors of 36 month survival were: the thickness of the right ventricle wall, size of the right atrium, end-diastolic volume and end-systolic volume of LV, indices of EDV and ESV of LV, urinary acid level, value of LVEF. In women the predictors of survivability during 3 years were the following parameters: BMI, DM type 2 in an anamnesis, end-diastolic size of LV, end-systolic size of LV, blood glucose level, LVEF.Conclusion. The survivability of men and women with CHF with decreased LVEF during 36 months didn\u27t reliably differ and was 49 and 51 % respectively. But predictors of the lethal outcome in men and women essentially differed during 36 months, and their number is essentially higher in men

On the Best Approximation of the Infinitesimal Generator of a Contraction Semigroup in A Hilbert Space

Let A be the infinitesimal generator of a strongly continuous contraction semigroup in a Hilbert space H. We give an upper estimate for the best approximation of the operator A by bounded linear operators with a prescribed norm in the space H on the class Q2={x∈D(A2):∥A2x∥≤1}, where D(A2) denotes the domain of A2.This work was supported by the Russian Foundation for Basic Research (project no. 15-01-02705), the Program for State Support of Leading Scientific Schools of the Russian Federation (project no.NSh-9356.2016.1), and by the Russian Academic Excellence Project (agreement no. 02.A03.21.0006 of August 27, 2013, between the Ministry of Education and Science of the Russian Federation and the Ural Federal University)

ON THE BEST APPROXIMATION OF THE INFINITESIMAL GENERATOR OF A CONTRACTION SEMIGROUP IN A HILBERT SPACE

Let $A$ be the infinitesimal generator  of a strongly continuous contraction semigroup in a  Hilbert space $H$.   We give an upper estimate for the best approximation of the operator $A$ by bounded linear operators with a prescribed norm  in the space $H$ on the class $Q_2 = \{x\in \mathcal{D}(A^2) : \|A^2 x\| \leq 1\}$,  where $\mathcal D(A^2)$ denotes the domain of $A^2$

COVID-19-related cardiac lesion: The questions of pathogenesis and diagnostics

Coronavirus infection is still a topic of interest in the medical community today. Among the heterogeneous clinical manifestations of this disease, lesions of cardiac structures often occur. They are mainly inflammatory in nature and can be acute or delayed. Aside from myocarditis, coronavirus infection can induce cardiac injuries, including acute coronary syndrome, thromboembolic events, heart failure, and heart rhythm disturbances. It is well known that the prognosis for patients with cardiac lesions significantly worsens; timely diagnosis and treatment initiation play an important role in preventing severe complications. This review presents the most recent literature data on the pathogenesis of cardiac lesions in COVID-19 patients and discusses the rational diagnosis of this pathology using modern techniques, such as laboratory, functional imaging (cardiac magnetic resonance is the most important of these), and invasive ones. It is now established that diagnosing myocarditis caused by coronavirus infection differs fundamentally from diagnosing other types of myocarditis. Furthermore, the main aspects of inflammatory heart lesions associated with COVID-19 vaccination are discussed, as this complication occurs more frequently than is commonly believed. It is often used as a rationale for refusing vaccination; however, this decision may severely affect the individual and the population

Migraine and neck pain: Mechanisms of comorbidity

Neck pain and migraine are common diseases. Neck pain seldom occurs in a patient with migraine. However, the relationship between migraine and neck pain has been inadequately investigated.Objective: to analyze neck pain in patients with migraine to determine possible comorbidity mechanisms of these diseases.Patients and methods. The investigation enrolled 63 patients with chronic migraine (CM) and 40 with episodic migraine (EM) diagnosed in accordance with the International Classification of Headache Disorders, 3rd edition (ICHD-3). Winking reflex (WR) and nociceptive flexion reflex (NFR) were examined to evaluate the function of antinociceptive systems.Results. In the patients with CM, neck pain was more common than in those with EM (53.03% versus 14.02%); and panful tenderness, sensitivity, and tension of neck muscles were more marked. There was also a significant reduction in WR and NFR thresholds. Neck pain was noted to be an integral component of the pathogenesis of CM in a large number of patients with this condition. The authors proposed several pathophysiological mechanisms of a relationship between migraine and neck pain. Neck muscles and craniovertebral junction areas serve as a source for the arrival of nociceptive pain pulses in the central nervous system (peripheral sensitization), promoting pain chronization. Muscle dysfunction in this area may be, in turn, a reflection of central sensitization and impaired descending pain control

Identification of a Response Amplitude Operator for Ships

At the European Study Group Mathematics with Industry 2012 in Eindhoven, the Maritime Research Institute Netherlands (MARIN) presented the problem of identifying the response amplitude operator (RAO) for a ship, given input information on the amplitudes of the sea waves and output information on the movement of the ship. We approach the problem from a threefold perspective: a direct least-squares approach, an approach based on truncated Fourier series, and an approach using low-dimensional measures of the RAO. We give a few recommendations for possible further investigations