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Introduction. Allergic rhinitis (AR) is a common condition that has considerable impact on patients’ quality of life. Moreover, it is the risk factor for asthma development. Therefore, achieving control of AR remains crucial.Aim. To analyze comparative efficacy of fixed-dose combination of olopatadine hydrochloride – mometasone furoate versus combination of intranasal corticosteroids with second generation oral antihistamines.Materials and methods. Seventy-five patients (ages 19–59) mainly with moderate severity of AR enrolled the study. Group 1 (29 patients) was given a fixed-dose combination of olopatadine hydrochloride – mometasone furoate (Ryaltris) in 2 sprays (25/600 mcg) in each nostril twice daily, whereas group 2 (46 patients) – intranasal corticosteroids with second generation oral antihistamines for 14 days. The efficacy was evaluated using validated questionnaires and scales (TNSS, TOSS, VAS, SNOT-22) before, during and after the treatment is complete.Results and discussion. We revealed AR and allergic conjunctivitis symptoms improvement as well as quality of life parameters. Nevertheless, disease control was achieved earlier (on day 2 of treatment) in group 1, while in group 2 – only on day 4.Conclusions. Our study showed comparable efficacy of fixed-dose combination of olopatadine hydrochloride – mometasone furoate (Ryaltris) and combination of intranasal corticosteroids with second generation oral antihistamines. However, fixed-dose combination topical therapy is associated with lower risk of adverse reactions and leads to early control of AR and allergic conjunctivitis symptoms. Besides, fixed combination use adjusts adherence to treatment.

The aim of the study was to investigate the effect of fine suspended particles in the atmospheric air on the formation and course of allergic and non-allergic phenotypes of the T2 endotype of bronchial asthma (BA) using the case-control study. Materials and methods. BA patients were selected in the course of seeking medical help. The groups were formed on the base of matching criteria (gender, age, body mass index, level of education), supplemented by the collection of information about potential cofounders. Based on the data on monitoring the content of fine suspended particles in the atmospheric air of Kazan, the average annual and maximum concentrations of PM2.5 and PM10 fractions were determined in the residential areas. The group of “cases” included forty patients with an allergic phenotype and 42 patients with an eosinophilic non-allergic phenotype of bronchial asthma, the control group included forty eight people. Additionally, sampling of atmospheric air was carried out using an 8-stage impactor to assess the content of bacterial endotoxin, and elemental composition. Results. Higher levels of pollution with fine suspended particles were demonstrated in the areas of residence of BA patients, comparing to the control group. An increase in the average annual concentration of the PM2.5 by 10 µg/m3 increases the odds of the eosinophilic non-allergic BA phenotype in adults by 4.76 times. The odds of the allergic phenotype of bronchial asthma increases in the presence of bacterial endotoxin - 1.32 times per 0.01 EU/m3 of endotoxin in the 3.2-18 µm size fraction. A more severe course of the eosinophilic non-allergic BA phenotype was noted at higher average annual concentrations of the PM2.5. The control of allergic asthma depends on the bacterial contamination of the aerosol. Limitations of the study are related to the use of geospatial approach to assess personalized average annual and maximum annual concentrations. Conclusion. The role of fine suspended particles in the atmospheric air in the development of bronchial asthma in adults has been shown. Various mechanisms were established to be involved in the formation of the clinical picture of the eosinophilic non-allergic and allergic phenotypes of bronchial asthma.

The article discusses a new method for constructing particular solutions of nonlinear integrable lattices, based on the concept of a generalized invariant manifold (GIM). In contrast to the finite-gap integration method, instead of the eigenfunctions of the Lax operators, we use a joint solution of the linearized equation and GIM. This makes it possible to derive Dubrovin type equations not only in the time variable t, but also in the spatial discrete variable n. We illustrate the efficiency of the method using the Ruijsenaars–Toda lattice as an example, for which we find some new solutions: a real and bounded particular solution in the form of a kink, a periodic solution expressed in terms of Jacobi elliptic functions and a solution expressed through Weierstrass ℘ -function.

Introduction. The Children’s Republican Clinical Hospital of the Ministry of Health of the Republic of Tatarstan in Kazan is a hospital with 1,180 beds, designed for planned and emergency care throughout the Republic of Tatarstan. In stationary medical institutions there are 5 intensive care units, ambulance transport services with numerous resuscitation vehicles, and an air ambulance service. Every year, more than 10,000 (up to 15,000) planned surgical interventions are performed at the hospital, and almost all patients of varying severity are treated at the institution. As in all world practice, despite the high level of professionalism of nursing staff and doctors, the widespread use of modern peripheral and central venous catheters, ultrasound equipment and other devices to assist in catheterization, the rate of unsuccessful catheterization attempts remains quite high, especially in the emergency segment. medical care.Tasks: systematization of knowledge on intraosseous vascular access (IVA), analysis of the work performed. At the current stage of providing medical care to the pediatric population, our hospital maintains a protocol for vascular access in pediatrics and has developed an internal protocol for intraosseous access to analyze the work done, take into account complications and evaluate its effectiveness.Materials and methods. An analysis was carried out for the installation of intraosseous vascular access for two-year periods, starting from 2015. This article considers the period of 2017–2018, for which the most complete data were collected. During this period, 58 protocols were recorded in children of various age groups with various pathologies in a critical situation.

We assign some kind of invariant manifolds to a given integrable PDE (its discrete or semidiscrete variant). First, we linearize the equation around its arbitrary solution u. Then we construct a differential (respectively, difference) equation compatible with the linearized equation for any choice of u. This equation defines a surface called a generalized invariant manifold. In a sense, the manifold generalizes the symmetry, which is also a solution to the linearized equation. In this paper, we concentrate on continuous and discrete models of hyperbolic type. It is known that such kinds of equations have two hierarchies of symmetries, corresponding to the characteristic directions. We have shown that a properly chosen generalized invariant manifold allows one to construct recursion operators that generate these symmetries. It is surprising that both recursion operators are related to different parametrizations of the same invariant manifold. Therefore, knowing one of the recursion operators for the hyperbolic type integrable equation (having no pseudo-constants) we can immediately find the second one.

A study is made of the evolution of pulsed pressure perturbations in a pipeline filled with a gas–droplet medium, which represents "moist" methane at a below-dewpoint temperature, and having a portion in the form of an extended channel constriction. For this process, the authors have adopted a theoretical model of propagation of acoustic waves in the longwave range in the gas–droplet medium. The problem of propagation and reflection of pulsed pressure perturbations in a horizontal pipeline having a portion of constriction because of hydrate deposits is solved by the method of fast Fourier transformation. Results of dispersion analysis of acoustic equations in a vapor–gas–droplet system are presented. Based on them, for real values of the parameters of pipelines, and also of the parameters of vapor–gas–droplet systems in them, the authors have obtained dependences of the phase velocity and the attenuation coefficient on the frequency of perturbation of an acoustic wave and the volume content of a suspended phase (water droplets). Also, an analysis has been made of the manifestation of viscosity and heat conduction in the wall pipeline layer saturated with water droplets. For the coefficients of reflection and transmission of acoustic signals at the sites of constriction of the pipeline because of hydrate deposits, use has been made of the existing formulas. Results of numerical calculations have been presented, which illustrate the evolution of pulsed signals of varying duration and show the influence of the thickness of a gas–hydrate layer on the interior pipeline wall. It has been shown that growth in the thickness of the hydrate deposits on the wall and increase in the duration of the pulsed signal cause the amplitude of the returned signals (echo) to grow.

This study featured types and components of tolerance in students that majored in social science, natural science, and humanities. The paper focuses on various definitions of this term and its regional specifics. The obtained data underwent a correlation analysis, Student's t-test for independent samples, and a content analysis. The sample consisted of 91 people aged 18–21 (33 % male). The methods of primary data collection included the Index of Tolerance questionnaire developed by G. U. Soldatova, O. A. Kravtsova, O. E. Khukhlaeva, and L. A. Shaigerova; the Questionnaire of Communicative Tolerance by V. V. Boyko; the Homophobia Index Questionnaire by V. V. Hudson and V. A. Rickets; the Types and Components of Tolerance vs. Intolerance by G. L. Bardier; and a sentence competition test. The interpersonal component of tolerance had the highest mean score among other components, regardless of the major. The article highlights the way humanities degree students see tolerance. The results can be used in training programs that adapt students to the multicultural environment of the university.

In the article we discuss the notion of the generalized invariant manifold introduced in our previous study. In the literature the method of the differential constraints is well known as a tool for constructing particular solutions for the nonlinear partial differential equations. Its essence is in adding to the nonlinear PDE, a much simpler, as a rule ordinary, differential equation, compatible with the given one. Then any solution of the ODE is a particular solution of the PDE as well. However the main problem is to find this compatible ODE. Our generalization is that we look for an ordinary differential equation that is compatible not with the nonlinear partial differential equation itself, but with its linearization. Such a generalized invariant manifold is effectively sought. Moreover, it allows one to construct such important attributes of integrability theory as Lax pairs and recursion operators for integrable nonlinear equations. In this paper, we show that they provide a way to construct particular solutions to the equation as well.

The research featured family values of the so-called Generation Z. The survey involved an authentic survey, S. S. Nosov’s Family Values Questionnaire, and the Morphological Test of Life Values developed by V. F. Sopov and L. V. Karpushina. A comparative analysis proved that Generation Z and Generation Y have both similar and different views on family values. The sphere of marriage and parenting had more differences, while the sphere of kinship showed more similarities. Representatives of Generation Z appeared to accept the idea of cohabitation; they also tended to get married relatively late in life. The gap between the optimal age of marriage for men and women proved to be quite narrow, while the age of first childbirth for women approximated that of men. In general, Generation Z shifted to an egalitarian family type. Unlike Generation Y, members of Generation Z valued spiritual satisfaction and underestimated achievements. In the hierarchy of family life values, they focused on spiritual satisfaction, self-development, individuality, and active social contacts. The research results can be used in health and family life education programs.

Toxic epidermal necrolysis (TEN) is a severe drug allergy. The objective was to analyze the clinical experience of 17 children of different age with toxic epidermal necrolysis. The authors found that medications against infection diseases were the most common reason for the development of the disease. In some cases we observed the delayed diagnosis, therapy without consideration of causative agents, and wrong doses of corticosteroids. The majority of cases require combined use of corticosteroids and intravenous immunoglobulins, however bacterial complications are possible in some cases.

The review sets out modern ideas about the mechanisms of action of gamma-aminobutyric acid (GABA) in the central nervous system and other organs and systems. Current experimental and clinical studies have shown that GABA has numerous effects: neuroprotective, antihypertensive, antidiabetic, antitumor, anti-inflammatory, antimicrobial, anti-allergic, hepatoprotective, nephroprotective and enteroprotective, and others, which are currently the subject for study by biologists, physiologists, and physicians. Synthetic GABA analogues are widely used in clinical practice. One of these drugs is aminophenylbutyric acid hydrochloride (Anvifen®) that has demonstrated high efficiency and safety in clinical practice.

Introduction. Suspended particles in ambient air of cities increase the risk of developing respiratory and cardiovascular diseases. At the same time, data on the role of suspended particles in the formation and complication of the course of bronchial asthma (BA) are extremely limited. The aim of study was to substantiate the design of a study to study the effect of fine suspended particles in atmospheric air on the development of the T2 endotype of BA. The design of a "case-control" study was developed and implemented, including patients with the T2-endotype of BA and persons in the control group. In order to verify the diagnosis of BA, General clinical methods of examination and specific allergological examination are used. In parallel, the quantitative characteristics and qualitative composition of suspended particles in atmospheric air are studied with the determination of the mass of suspended particles, dispersion, chemical and microbiological (muldi-tof mass spectrometry, PCR analysis) composition. Atmospheric air samples will be collected using a cascade impactor in the area where patients with bronchial asthma and control groups live. For each fraction, the following will be analyzed: suspended particle mass, dispersion, chemical and microbiological (muldi-tof mass spectrometry, PCR analysis) composition. Conclusions. The study will assess the risk of T2-endotype formation of bronchial asthma with various quantitative and qualitative characteristics of suspended microparticles in the atmospheric air.

In this paper, we study a system of nonlinear equations on a square graph related to the affine algebra A(1)1 . This system is the simplest representative of the class of discrete systems corresponding to affine Lie algebras. We find the Lax representation and construct hierarchies of higher symmetries. In neighborhoods of singular points ⋋ = 0 and ⋋ = ∞, we construct formal asymptotic expansions of eigenfunctions of the Lax pair and, based on these expansions, find series of local conservation laws for the system considered.

Launch-vehicle primary structures like cylindrical shells are increasingly being built as monolithic composite and sandwich composite shells. These imperfection sensitive shells are subjected to axial compression due to the weight of the upper structural elements and tend to buckle under axial compression. In the case of composite shells the buckling load and imperfection sensitivity depend on the laminate stacking sequence. Within this paper multi-objective optimizations for the laminate stacking sequence of composite cylinder under axial compression are performed. The optimization is based on different geometric imperfection types and a brute force approach for three different ply angles . Decision tree-based machine learning is applied to derive general design recommendations which lead to maximum buckling load and a minimum imperfection sensitivity. The design recommendation are based on the relative membrane, bending, in-plane shear and twisting stiffnesses. Several optimal laminate stacking sequences are generated and compared with similar laminate configurations from literature. The results show that the design recommendations of this article lead to high-performance cylinders which outperform comparable composite shells considerably. The results of this article may be the basis for future lightweight design of sandwich and monolithic composite cylinders of modern launch-vehicle primary structures.

The method of constructing particular solutions to nonlinear partial differential equations based on the notion of differential constraint (or invariant manifold) is well known in the literature, see (Yanenko, 1961; Sidorov et al., 1984). The matter of the method is to add a compatible equation to a given equation and as a rule, the compatible equation is simpler. Such technique allows one to find particular solutions to a studied equation. In works (Pavlova et al., 2017; Habibullin et al., 2017, 2018; Khakimova, 2018; Habibullin et al., 2016, 2017, 2018) there was proposed a scheme for constructing the Lax pairs and recursion operators for integrable partial differential equations based on the use of similar idea. A suitable generalization is to impose a differential constraint not on the equation, but on its linearization. The resulting equation is referred to as a generalized invariant manifold. In works (Pavlova et al., 2017; Habibullin et al., 2017, 2018; Khakimova, 2018; Habibullin et al., 2016, 2017, 2018) it is shown that generalized invariant varieties allow efficient construction of Lax pairs and recursion operators of integrable equations. The research was supported by the RAS Presidium Program «Nonlinear dynamics: fundamental problems and applications».

A study has been made of the process of pressure relaxation in a liquid-filled tank with impaired leakproofness, which is found in the ground. Assuming that the leak rate is limited by filtration characteristics of the ground surrounding the tank, the authors have constructed a theoretical model representing a linear integral equation. Here, the obtained equation has an exact analytical solution. On the basis of a numerical analysis of this solution, the authors have analyzed the influence of the scale of the damaged portion of tank walls, the permeability of the ground, and also the rheological properties of the liquid on the rate of pressure relaxation (decay) in the tank after its sudden pressure testing.

Evolution of pressure perturbations propagating in pipeline filled with gas-and-drop medium representing “wet” methane at temperature below dew point and having damaged section, in form of extended narrowing of channel due to hydrate plug, is investigated. Hydrate formation is due to the presence of water (or its vapours) and gas, the components of which dissolve in water under certain conditions form a solid phase. Hydrate deposits help to reduce the cross-country capacity of gas pipelines and therefore their detection is a pressing task. It is proposed to solve the problem using acoustic methods. For this purpose mathematical model of propagation of acoustic waves in long-wave range in gas-and-droplet medium is considered. The horizontal pipeline appears semi-pointed, the solution is sought in the form of a harmonic wave. Wave is one-dimensional, having small amplitude of oscillations. Based on dispersion equations, dependence of phase velocity and attenuation coefficient on frequency of acoustic wave disturbance and on volume content of suspended phase (water droplets) are built. In the high frequency region, the attenuation coefficient increases with the volume content. The formulas for reflection and passage coefficients are derived taking into account pipeline narrowing due to hydrate deposits. The results of numerical calculations illustrating the dynamics of pulse signals depending on the thickness of the gas hydrate on the inner wall of the pipeline are presented. Calculations are based on forward and backward Fourier transformations and the use of software. It is established that the greater the hydrate deposit on the wall in thickness, the greater the amplitude of the returned reflected signal.

This article studies the process of relaxation of the pressure in a tank with the damaged area of the wall after pressure-testing. The authors use different methods for the diagnosis of the technical condition of objects of petroleum products storage. Pressure testing is one of nondestructive methods. The rate of pressure decrease is characteristic of the system tightness. This article studies the cases of ground and underground location of the tank. Pressure testing involves excess pressure inside of a tank and observing its decrease. Over time, one can assess the integrity of the system. This has required creating mathematical models to account the filtration of the liquid depending on the location of the tank. The results include the analytical solution of the task and the formulas for describing the dependence of the relaxation time of pressure in the tank from the liquid and soil parameters, geometry of the tank, and the damaged portion of the wall. The two- and three-dimensional cases of liquids filtration for the case of underground location of the tank were considered. The results of some numerical calculations of the dependence of reduction time and the time of half-life pressure from the area of the damaged portion of the wall were shown. The obtained solutions allow assessing the extent of the damaged area by the pressure testing with known values of tank, liquid, and soil.

The article presents an overview of the development of hematology service in the Republic of Tatarstan. The well-known scientist Nikolay Konstantinovich Goryaev (1875-1943), who worked in Kazan for a long time, began to develop this direction and after passing an internship in Germany proposed an improved device for calculating the blood elements known throughout the world. Adherents of Professor Goryaev continued research in the field of hematology, a blood transfusion station was organized. Professor S.I. Sherman proposed new methods of diagnosis and treatment of B12 deficiency anemia. Professor Sh.I. Ratner studied the changes in the blood picture in diseases of the abdominal cavity. The first 15 specialized hematological beds were opened in 1968 in the hospital named “Old Clinic”. The physician who treated such patients was Rakhil Sholomovna Dashevskaya, PhD. At present, hematology service is provided by three hospitals in Kazan, hematological and therapeutical beds in Naberezhnye Chelny and Nizhnekamsk, outpatient hematology service in Zelenodolsk. In recent years, the introduction of stem cell therapy has begun, and modern combined methods of chemotherapy have been introduced.

The problem of anthropogenic impact of the Tudakul reservoir has not been spared. In the first years of the reservoir’s existence, its ichthyofauna was formed by the fish of the Zarafshan River, which were represented by both rheophiles and limnophiles, and initially it consisted of 11 aboriginal species and introduced fish. This paper gives a brief physical-geographical, hydrological, hydrochemical, hydrobiological characteristics of the Tudakul reservoir. An assessment of the ecological state of the reservoir, ichthyofauna and fish catch in it over the past decade is given. Recommendations for the rational use of the Tudakul reservoir are given.

The study was carried out in 2014-2018 at the Tudakul reservoir, Uzbekistan. Samples included 278 European bream (Abramis brama), and 83 Amur white bream (Parabramis pekinensis). The age, total length and weight of the fish varied from 1 to 5 years, from 14 to 50 cm, from 30 to 1,405 g for the European bream and from 1 to 6 years, from 24 to 53.5 cm and 105 – 2,138 g for the white Amur bream and European bream, respectively. The relationship between total length (TL) and weight (W) is described by the equation W = 0.005 * TL3.2555 (r = 0.98) for European bream and W = 0.005 * TL3.201 (r = 0.96) for white Amur bream. Recovered average growth rate of European bream: TL1 - 13.5 cm; TL2 - 28.1 cm, TL3 - 37.95 cm, TL4 - 42.6 cm, TL5 - 48.6 cm.The average height of the Amur white bream: TL1 - 12.6 cm, TL2 - 23.3 cm, TL3 - 31.5 cm, TL4 - 37.9 cm, TL5 - 41.7 cm, TL6 - 44.2 cm. Lee’s phenomenon did not appear. All yearling fish were juvenile. In 2-year-old fish of both sexes of both species, the gonads were at stage II. Males and females of both species reached their first maturity at 3-4 years of age, when the total body length of the European bream was 30–32 cm, and the Amur white bream was 34–35 cm.

To develop and validate a Russian version of The Central Sensitization Inventory (CSI-R).The study included 3 stages: 1) direct and reverse translation, linguistic validation of the questionnaire; 2) assessment of internal consistency, reliability and sensitivity (The Russian version of CSI-R is valid, reliable and can be used in clinical practice as a diagnostic tool for revealing central sensitization. The study of the sensitivity of the questionnaire in patients during drug therapy proved its effectiveness in assessing the dynamics of the disease and the effect of therapy.Создание и психометрическая валидизация русскоязычного варианта Опросника центральной сенситизации (CSI-R).Исследование включало 3 этапа: 1) прямой и обратный переводы, лингвистическая валидизация опросника; 2) оценка внутренней согласованности, надежности и чувствительности (Русскоязычная версия опросника (CSI-R) является валидной, надежной и может применяться в клинической практике как диагностический инструмент для выявления центральной сенситизации. Исследование чувствительности опросника у пациентов на фоне лекарственной терапии доказало его эффективность для оценки динамики заболевания и эффекта терапии.

We suggest an algorithm for seeking recursion operators for nonlinear integrable equations. We find that the recursion operator R can be represented as a ratio of the form R = L1−1 L2, where the linear differential operators L1 and L2 are chosen such that the ordinary differential equation (L2 −λL1)U = 0 is consistent with the linearization of the given nonlinear integrable equation for any value of the parameter λ ∈ C. To construct the operator L1, we use the concept of an invariant manifold, which is a generalization of a symmetry. To seek L2, we then take an auxiliary linear equation related to the linearized equation by a Darboux transformation. It is remarkable that the equation L1 $$\tilde U$$ = L2U defines a B¨acklund transformation mapping a solution U of the linearized equation to another solution $$\tilde U$$ of the same equation. We discuss the connection of the invariant manifold with the Lax pairs and the Dubrovin equations.

The education system is becoming global in nature, covering not only the traditional exchange of students and teachers, but also issues of cross-border investment and competition of universities in the global educational services market, participation and (or) initiation by employers of new educational programs, considering the changing requirements of professional standards, etc. A modern industrial enterprise is high-tech and the role of the technological factor is increasing. This makes special demands on his staffing. The existing education system often lags the increasing pace of technological change. This is due to both the conservatism of the system and its personnel, material and technical and information support. Therefore, the problems of training young specialists for the modern labor market are being updated. The purpose of the study: to identify the problems of the modern labor market for a high-tech enterprise and propose a solution to these problems based on increased interaction between these enterprises and educational institutions. Methodology: systemic, strategic, comparative and statistical analysis, questioning method.

The dynamics of a pulsed signal propagating in an underground pipeline with a damaged section is investigated. Pressure waves propagating in a linear pipeline filled with a fluid are considered. Due to viscous friction and thermal conductivity, dissipation is taken into account in a thin liquid or gas layer near the wall. It is assumed that the damaged pipeline section is a reflecting surface. Conditions on this surfaces are obtained under the assumption that the rate of liquid leakage during wave propagation through the damaged section is determined by the permeability of the soil. It is shown that in weakly permeable soils, signals do not provide full information on damage, and in well-permeable soils, only short (high-frequency) pulsed signals can be used to detect damage.

A study is made of the evolution of pressure perturbations that propagate in a tubular channel filled with liquid or gas and having a damaged portion in the form of fairly large slots when their hydraulic resistance is minor. For this purpose, the authors have adopted a mathematical model taking account of viscous friction and of the transfer of heat in a thin layer of the liquid (or the gas) near the wall. Based on this model, dispersion relations have been obtained for the processes of propagation and reflection of harmonic waves from the damaged portion. An analysis has been made of the dependences of the phase velocity, the attenuation factor, and also the coefficients of reflection and transmission on the circular frequency, the physical properties of the liquid or the gas, and also the size of damage. The authors have presented results illustrating the dynamics of pulsed signals as a function of the distance to the damaged portion from the inlet cross section of the channel, the damage scale, and of the form of the medium (liquid or a gas) in the channel.

Idiopathic generalized dystonia is a group of neurodegenerative diseases primarily charecterized by dystonic hyperkinetic disorder (irregular slow involuntary movements of different body parts accompanied by specific muscle tone changes and pathological poses). A 54-year-old female was admitted with various complaints. The leading syndrome was extrapyramidal due to which the differential diagnosis included Parkinson’s disease, multiple system atrophy, corticobasal degeneration, etc. The diagnosis of idiopathic generalized dystonia, in the form of lower extremity hyperkinesia with dystonic equinus of the left foot and hallux extension and cheirospasm, was made by a method of exclusion. The clinical case described in the article illustrates variety of clinical manifestations of the disease imitating clinical presentation of various neurological and psychiatric disorders, complexity of diagnostic search and importance of timely diagnosis of this disease.

The purpose of this article is to develop an algebraic approach to the problem of integrable classification of differential-difference equations with one continuous and two discrete variables. As a classification criterion, we put forward the following hypothesis. Any integrable equation of the type under consideration admits an infinite sequence of finite-field Darboux-integrable reductions. The property of Darboux integrability of a finite-field system is formalized as finite-dimensionality condition of its characteristic Lie-Rinehart algebras. That allows one to derive effective integrability conditions in the form of differential equations on the right hand side of the equation under study. To test the hypothesis, we use known integrable equations from the class under consideration. In this article, we show that all known examples do have this property., Comment: 24 pages

We continue the previously started study of the development of a direct method for constructing the Lax pair for a given integrable equation. This approach does not require any addition assumptions about the properties of the equation. As one equation of the Lax pair, we take the linearization of the considered nonlinear equation, and the second equation of the pair is related to its generalized invariant manifold. The problem of seeking the second equation reduces to simple but rather cumbersome calculations and, as examples show, is effectively solvable. It is remarkable that the second equation of this pair allows easily finding a recursion operator describing the hierarchy of higher symmetries of the equation. At first glance, the Lax pairs thus obtained differ from usual ones in having a higher order or a higher matrix dimensionality. We show with examples that they reduce to the usual pairs by reducing their order. As an example, we consider an integrable double discrete system of exponential type and its higher symmetry for which we give the Lax pair and construct the conservation laws.

For the design of thin-walled spherical shells under external pressure empirical knockdown factors are applied. These knockdown factors are based on experimental results from the beginning of the 20th century and have been shown to be very conservative for modern shell structures. In order to determine less conservative and physically based knockdown factors for the design of spherical shells, different analytical and numerical design approaches have been developed. In this paper common as well as new shell design approaches are presented in detail and evaluated regarding the lower-bound buckling pressure. Among these design approaches are the reduced stiffness method, measured geometric imperfections and perturbation approaches. Important analysis and modeling details of each design approach are described, and test examples are given and validated. Advantages and disadvantages of each approach are listed, and design recommendations are given. Practical shell buckling design examples are demonstrated by means of a tori-spherical bulkhead and a deep-sea spherical pressure hull. In addition, a collection of about 700 experimental knockdown factors for spherical shells under external pressure is given in the Elsevier repository.

Vascular cognitive impairment (VCI) and vascular dementia are the most common forms of cognitive disorder associated with cerebrovascular disease and related to increased morbidity and mortality among the older population. Growing evidence suggests the contribution of blood-pressure variability, cardiac arrhythmia, hyperactivation of the renin–angiotensin–aldosterone system, endothelial dysfunction, vascular remodeling and stiffness, different angiopathies, neural tissue homeostasis, and systemic metabolic disorders to the pathophysiology of VCI. In this review, we focus on factors contributing to cerebrovascular disease, neurovascular unit alterations, and novel approaches to cognitive improvement in patients with cognitive decline. One of the important factors associated with the neuronal causes of VCI is the S100B protein, which can affect the expression of cytokines in the brain, support homeostasis, and regulate processes of differentiation, repair, and apoptosis of the nervous tissue. Since the pathological basis of VCI is complex and diverse, treatment affecting the mechanisms of cognitive disorders should be developed. The prospective role of a novel complex drug consisting of released–active antibodies to S100 and to endothelial NO synthase in VCI treatment is highlighted.

The review highlights the current understanding of the role of autoimmune neuroinflammation in the pathogenesis of vascular, neurodegenerative and other diseases of the nervous system. The mechanisms of the response of the resident cells of the central nervous system (microglia, astrocytes) and peripheral cells of the immune system are considered. Possible therapeutic potential of phosphodiesterase inhibitors, which have antiplatelet properties and the ability to suppress autoimmune inflammation, are outlined. The authors consider dipyridamole, an inhibitor of phosphodiesterase, as a promising drug.В обзоре освещается современное понимание роли аутоиммунного нейровоспаления в патогенезе сосудистых, нейродегенеративных и других заболеваний нервной системы. Рассматриваются механизмы ответа резидентных клеток ЦНС (глия, астроциты) и периферических клеток иммунной системы. Изложены потенциальные терапевтические возможности ингибиторов фосфодиэстеразы, которые обладают антиагрегантными свойствами и способностью подавлять аутоиммунное воспаление. Одним из перспективных препаратов рассматривается ингибитор фосфодиэстеразы — дипиридамол.

A crucial event in the pathogenesis of Parkinson's disease is the death of dopaminergic neurons of the nigrostriatal system, which are responsible for the regulation of motor function. Motor symptoms first appear in patients 20-30 years after the onset of the neurodegeneration, when there has been a loss of an essential number of neurons and depletion of compensatory reserves of the brain, which explains the low efficiency of treatment. Therefore, the development of a technology for the diagnosing of Parkinson's disease at the preclinical stage is of a high priority in neurology. In this study, we have developed at an experimental model a fundamentally novel for neurology approach for diagnosis of Parkinson's disease at the preclinical stage. This methodology, widely used for the diagnosis of chronic diseases in the internal medicine, is based on the application of a challenge test that temporarily increases the latent failure of a specific functional system, thereby inducing the short-term appearance of clinical symptoms. The provocation test was developed by a systemic administration of α-methyl-p-tyrosine (αMpT), a reversible inhibitor of tyrosine hydroxylase to MPTP-treated mice at the presymptomatic stage of parkinsonism. For this, we first selected a minimum dose of αMpT, which caused a decrease of the dopamine level in the striatum of normal mice below the threshold at which motor dysfunctions appear. Then, we found the maximum dose of αMpT at which a loss of dopamine in the striatum of normal mice did not reach the threshold level, and motor behavior was not impaired. We showed that αMpT at this dose induced a decrease of the dopamine concentration in the striatum of MPTP-treated mice at the presymptomatic stage of parkinsonism below a threshold level that results in the impairment of motor behavior. Finally, we proved that αMpT exerts a temporal and reversible influence on the nigrostriatal dopaminergic system of MPTP-treated mice with no long-term side effects on other catecholaminergic systems. Thus, the above experimental data strongly suggest that αMpT-based challenge test might be considered as the provocation test for Parkinson's disease diagnosis at the preclinical stage in the future clinical trials.

In order to identify the characteristics of personal fulfillment of volunteers, a comparative study using the methods of content analysis and survey was conducted. The results reveal the objectives and motives of participation in volunteering, and especially the level of satisfaction and personal fulfillment of volunteers. Statistically significant differences in terminal and instrumental values’ significance were revealed, as well as differences in the subjective evaluation of implemented values. The results are applicable to the work of public and youth organizations, in the activities of vocational guidance of young people, in the attraction of young people for volunteering, in the development of youth volunteer organizations, as well as in the development of teaching materials and courses for students of educational programs related to the work with youth.

The evolution of the pressure disturbances propagating in the tubular channel filled with liquid or gas and having a damaged portion in a sufficiently large gaps with low resistance. To this end, it adopted a mathematical model that takes into account the viscous friction and heat transfer in a thin layer of liquid (or gas) near the wall. On the basis of this model, dispersion equation for distribution processes and reflections from the damaged portion of harmonic waves. The dependence of the phase velocity, attenuation coefficient, as well as the reflection and transmission coefficients of the angular frequency and the physical properties of a liquid or gas. The results of calculations to illustrate the dynamics of pulse signals depending on the magnitude of damage, defined as the ratio of the gap area to the sectional area of the channel.

A notion of the generalized invariant manifold for a nonlinear integrable lattice is considered. Earlier it has been observed that this kind objects provide an effective tool for evaluating the recursion operators and Lax pairs. In this article we show with an example of the Volterra chain that the generalized invariant manifold can be used for constructing exact particular solutions as well. To this end we first find an invariant manifold depending on two constant parameters. Then we assume that ordinary difference equation defining the generalized invariant manifold has a solution polynomially depending on one of the spectral parameters and derive ordinary difference and differential equations, for the roots of the polynomials. Efficiency of the method is approved by some illustrative examples.

The review analyses the diseases and conditions caused by acute and chronic stress. The authors describe the pathogenesis of stress-induced disorders from the perspective of imbalance between stress-realizing and stress-limiting systems (sympathetic and parasympathetic nervous systems). The effects of acute and chronic stress on the cardiovascular, respiratory, and immune systems, the contribution of stress to the pathogenesis of skin diseases, the gastrointestinal tract, post-stroke disorders, headaches, and dizziness are considered. The authors highlight the role of gamma-aminobutyric acid (GABA) as the main mediator of stress-limiting systems in protecting the nervous system and target organs from the damaging effects of acute and chronic stress. The authors recommend aminophenylbutyric acid hydrochloride, an analogue of GABA, as a drug with protective effect on organs and systems that are exposed to the negative effects of acute and chronic stress. Aminophenylbutyric acid hydrochloride (anvifen) is successfully used in both adults and children, has good tolerance, has no significant drug interactions and side-effects.Обзор посвящен заболеваниям и состояниям, являющимся последствиями острого и хронического стресса. Авторы освещают патогенез стресс-индуцированных расстройств с позиций нарушения баланса между стресс-реализующими и стресс-лимитирующими системами (симпатическая и парасимпатическая нервные системы). Рассмотрено влияние острого и хронического стресса на кардиоваскулярную, респираторную, иммунную системы, вклад стресса в патогенез заболеваний кожи, желудочно-кишечного тракта, постинсультных расстройств, головных болей и головокружения. Авторы освещают роль гамма-аминомасляной кислоты (ГАМК) как основного медиатора стресс-лимитирующих систем в обеспечении защиты нервной системы и органов-мишеней от повреждающего действия острого и хронического стресса. Авторы рекомендуют аналог ГАМК — аминофенилмасляной кислоты гидрохлорид — как препарат, оказывающий протективное воздействие на органы и системы, подвергающиеся негативному влиянию острого и хронического стресса. Аминофенилмасляной кислоты гидрохлорид (Анвифен) успешно применяется как у взрослых, так и у детей, имеет хорошую переносимость, не имеет значимых лекарственных взаимодействий и побочных эффектов.