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In this research, density functional theory accompanied with linear combination of atomic orbitals (LCAO) method is applied to study the atomic and electronic structure of wurtzite and rocksalt ZnxMg1−xO pseudobinary compounds in their bulk phases. Calculated band gaps of ZnxMg1−xO solid solutions under study are further validated by means of spectroscopic ellipsometry and optical absorption. In agreement with an experiment, it is predicted that increase of Zn content in ZnxMg1−xO leads to narrowing of its band gap for both wurtzite and rocksalt phases. The calculated infra-red (IR) spectra show that the IR peaks are shifted towards larger frequencies along with decrease of Zn content. Presence of imaginary phonon frequencies in rocksalt ZnxMg1−xO of x > 0.625 allows us to suggest that it is necessary to use properly oriented substrates for epitaxial growth to overcome polycrystallinity inZnxMg1−xO thin films at concentration x = 0.4 – 0.6.

In this paper, we present a method for calculating the flows of a non-viscous fluid using the fast multipole method. The method is based on the fact that the computational complexity can be reduced to the level of O(N log N) . A two-dimensional problem of the flow of a non-viscous incompressible fluid is formulated in terms of vorticity and velocity. Further, the authors describe in detail the scheme, principles, as well as the positive and negative aspects of using the fast multipole method in the hydrodynamic problems. As a test of the algorithm, the authors consider an example of the Chaplygin-Lamb dipole. The results of numerical simulation of the dipole motion are presented, being implemented on C++ and Python platforms. Some conclusions are drawn about the motion of the vortex structure on the basis of the calculated results.

Introduction. Computed tomography is a non-invasive technique for examining patients and is helps to study the structures of the paranasal sinuses before endonasal interventions. The purpose of the study: to develop the criteria for assessing the architectonics of the ethmoid bone using computed tomography to determine the anatomical and topographic features of its structure, for endonasal surgical treatment planning. Tasks: to study variants of the anatomical structure of the nasal cavity, ethmoid bone, using the method of x-ray computed tomography and determine their role in planning tactics of endonasal surgical interventions. Materials and methods: 130 patients were examined, two groups of patients were formed — the first 65 people with cerebrospinal fluid lick, and the other 65 people with inflammatory diseases of the paranasal sinuses. All the patients underwent computed tomography, after which we studied the anatomical structure of the ethmoid plate of the ethmoid bone and cells of the ethmoid labyrinth and the contents of the paranasal sinuses were evaluated. Research results. The study revealed 6 basic anatomical and topographic types of the structure of the ethmoid bone. We evaluating the position of the plane of the ethmoid plate, a conclusion was made about the location of the roof of the nasal cavity: high, medium or low. The deeper the olfactory fossa is, the lower the general nasal passage is. Conclusions. The revealed low location of the roof of the nasal cavity was regarded as a predisposing factor to the development of iatrogenic cerebrospinal fluid lick with endoscopic endonasal intervention.

A technique has been developed for measuring the radii of curvature of optical parts. A scheme of the device based on a wavefront sensor is proposed, which is characterized by a minimum measurement error. The theoretical substantiation of the measurement technique is given. A number of methods that make it possible to measure the radii of curvature of optical parts are considered. The reasons for an increase in the measurement error are analyzed. The results of measurements according to the given methodology with an original prototype device are considered.

A methodology has been developed for measuring radius Rv and eccentricity (conic parameter k) of large concave aspherical mirrors using a wavefront sensor. Analytical expressions that directly relate Zernike coefficients a4 and a9 to parameters Rv and k of the mirror are obtained. It is shown that the technique does not require accurate mirror alignment before measurements. A computer analysis showed that the developed scheme enables measurements with errors of δRv < 0.1% and δk < 0.01 for mirrors with radii from 100 to 2000 mm and with errors of δRv < 0.01% and δk < 0.001 for mirrors with radii of more than 5000 mm.

Chronic rhinosinusitis (CRS) is a syndrome associated with persistent inflammation of the mucous membranes of the nose and paranasal sinuses. There are two forms of CRS: chronic rhinosinusitis with nasal polyposis (CRSwNP) and chronic rhinosinusitis without nasal polyposis (NP) (CRSsNP). Available data indicate that innate immunity, adaptive immunity, tissue remodeling, and influence of microorganisms can play a modified role in the development of CRSwNP. The genetic predisposition to the development of CRS is also possible. Today there are several groups of genes which influence the development of chronic rhinosinusitis. They include the genes associated with CFTR locus, HLA genes, genes of innate immunity, genes involved in the development of TH2-inflammatory reactions, genes responsible for tissue remodeling of paranasal sinuses, genes involved in the metabolism of arachidonic acid, genes of xenobiotic transformation, and other pro-inflammatory genes. Identification of genetic susceptibility to CRS would make it possible to develop personalized approaches for prevention, tactics, and effective treatment of chronic rhinosinusitis.

The authors report a clinical case of the fracture of the base of the skull with the concomitant damage to the sigmoid sinus, jugular vein, and internal carotid artery in the temporal bone pyramid. The injury was associated with massive bleeding from the external acoustic canal that resulted in the death of the patient.Представлен клинический случай перелома костей свода и основания черепа с повреждением сигмовидного синуса, яремной вены и внутренней сонной артерии в пирамидке височной кости, сопровождающегося массивным кровотечением из наружного слухового прохода и приведшего к летальному исходу.

For rational design and improvement of electronic and optical properties of water-splitting photocatalysts, the ability to control the band edge positions relative to the water redox potentials and the photoresponse as a function of environmental conditions is essential. We combine ab initio molecular dynamics simulations with ab initio many-body theoretical calculations to predict the bandgap and band edge energies, as well as the absorption spectrum of pristine and N- and S-doped TiO

A retrospective analysis of treatment was made in 127 adult patients with acute and chronic otitis media complicated by suppurative-inflammatory pathology of the brain. Purulent meningitis was revealed in 52 (40,9%) of hospitalized patients. Meningoencephalitis was often diagnosed in the cases of acute otitis media (15,4%) and in cases of chronic otitis (22,7%). The otogenic brain abscess was detected in 13,5% of otitis media cases and it was noted to be twice frequent (33,3%) in cases of purulent otitis media. The patients 124 (97,6%) have been operated. An extended mastoidotomy and antromastoidotomy were performed in the acute purulent otitis media. An extended radical operation on the ear was applied in case of chronic otitis media. Performance of craniotomy and complete removal of the abscess using modern systems of neuronavigation showed a higher clinical efficacy as compared with transtemporal approach during sanitizing intervention on the ear including the opening and abscess drainage in surgery of otogenic abscesses of the brain.

In this work, shear strain modeling in materials consisting of a thin polymer layer ([Formula: see text][Formula: see text]nm), adhesive bonded to a rigid substrate, considered not to be impacted by deformation, was performed. A discrete-continuum model of chains system with a given stiffness with polar groups is developed. The polymer chain was considered in the framework of the persistene model, and the polar groups were based on the lattice model on the tetragonal lattice. It was assumed that the main contribution to the energy of interchain interactions is due to the potential of the polar groups and was calculated using the Metropolis algorithm. The potential interactions between the nearest polar groups of chains included the energy of dipole–dipole interactions (Keesom energy) and the Lennard–Jones potential. It is taken into account that the possible orientations of the polar groups are determined by the average elongation of the chain. Calculations showed that the dependence of free energy on the interchain distance has two minima. The first minimum is characterized by the orientational ordering of the polar groups, the second — by their disordered state. The depth and position of the minima depend on temperature, bending stiffness of the chain, the modulus of the dipole moment of the polar groups and the depth of the potential well in the Lennard–Jones energy. A step-by-step simulation of shear strain in a polymer layer in an orientationally disordered state was carried out. The obtained stress–strain diagrams make it possible to estimate the value of the elastic limit and also to determine the stresses at the points of phase transitions from a disordered to an orientationally ordered state.

An analysis of the results of X-ray CT and MR-imaging was made in 46 patients aged from 13 to 78 years old. The patients were admitted to multifield hospitals in Kursk at the period from 2005 to 2015. The research included the nasal cavity, paranasal sinuses, mastoid and pyramid of the temporal bones and the brain. The study could be repeated with bolus contrast medium infusion. The condition of the patients was evaluated in dynamics at intervals of 5-7 days and these data was associated with clinical picture. The authors presents a complex of symptoms and an algorithm of differentiated X-ray diagnostics of diseases of the ENT organs and the main nosological forms of pyoinflammatory diseases of arachnoid membrane and substances of the brain.

The precision characteristics of devices based on two pairs of pentaprisms for parallel transfer of a beam of laser radiation are considered. The structure of the error of such devices is investigated. The article proposes a mathematical model by means of which the precision requirements of the initial setting of the pentaprisms and an algorithm for compensation of the error of parallel transfer by initial adjustment of the system may be determined.

The article provides a review of the causes of chronic osteomyelitis of the frontal bone and the symptoms of the disease. The authors described the epidemiology of osteomyelitis in Rostov and Kursk regions and analyzed histological findings of bone structures, obtained during the intervention in patients. The article presents computer-aided tomography images and specifies x-ray features of the frontal bone osteomyelitis. The authors describe a clinical case of the frontal bone chronic osteomyelitis.

The results on ultra-high-energy cosmic rays (UHECR) mass composition obtained with the Telescope Array surface detector are presented. The analysis employs the boosted decision tree (BDT) multivariate analysis built upon 14 observables related to both the properties of the shower front and the lateral distribution function. The multivariate classifier is trained with Monte-Carlo sets of events induced by the primary protons and iron. An average atomic mass of UHECR is presented for energies $10^{18.0}-10^{20.0}\ \mbox{eV}$. The average atomic mass of primary particles shows no significant energy dependence and corresponds to $\langle \ln A \rangle = 2.0 \pm 0.1 (stat.) \pm 0.44 (syst.)$. The result is compared to the mass composition obtained by the Telescope Array with $\mbox{X}_{\mbox{max}}$ technique along with the results of other experiments. Possible systematic errors of the method are discussed., Comment: 11 pages, 9 figures

We present the searches for photons and neutrinos with the 9 years of data of the Telescope Array surface detector (2008--2017). The both searches employ multivariate analysis with the classifier based on the Boosted Decision Tree. The diffuse flux limits for photons and down-going neutrinos are obtained for the primary energies greater than 1 EeV.

A model of the polymer system for computer simulation of deformation processes is presented. The model is a synthesis of analytical calculations (polymer chain in a tube) and a computer experiment (simulation of the orientational ordering of polar groups by the Monte Carlo method). Thanks to analytical calculations, this model makes it possible to analyse relatively large systems compared to other models. At the same time, the spent CPU time remains constant. The results of a simulation of stretching (stress-strain curves) a thin polymer film for various values of chain stiffness are given. The obtained curves have a characteristic “yield drop”.

Developed and experimentally justified constructive and technological method of increasing strength and reliability of point mechanical connection of composite panels by thermocompression installation along the contour of the hole of the intermediate element-less rigid composite liner. The effectiveness of the method is provided by reducing the stress concentration in the hole area and confirmed finite element analysis and results of mechanical tests of samples of connection.

The importance of the intracranial complications problem in acute and chronic focal processes of ENT organs is determined by their dominating position among the reasons of the fatal outcomes. The authors made retrospective analysis of all the clinical cases of inpatient treatment of 127 adult patients with acute and chronic otitis media, complicated with pyoinflammatory cerebral pathology. Chronical suppurative otitis media predominated in the general structure of the revealed otitis media pathology structure – 75 (59.0%) cases. Purulent meningitis was diagnosed in 52 (40.9%) received patients, in acute otitis it constituted 63.5% of the total intracranial complications, and in chronic otitis media – only 25.3%. Meningocephalitises have been diagnosed with equal frequency both in acute otitis media – 15.4%, and in chronic otitis media – 22.7%. Otogenic brain abscesses have been diagnosed only in 13.5% cases of acute suppurative otitis media, whilst in chronic suppurative otitis media they have been revealed twice more frequent – 33.3%. 124 (98%) patients underwent surgery due to otogenic intracranial complications. For the purpose of sanation of the primary focus of infection in the ear the following therapy was conducted: in acute supportive otitis media – extended mastoidotomy, antromastoidotomy; in chronic suppurative otitis media – extended radical ear surgery. In surgical therapy of otogenic brain abscess, craniotomy and complete removing of the brain abscess using advanced neuronavigation systems proved higher clinical efficacy compared to transtemporal access in the course of sanation intervention in the ear with the abscess incision and drainage. Nowadays, the main clinical features of otogeneous intracranial complications are: severe central nervous system inflammatory damage with prevalence of cerebral and meningeal symptoms, high severity of the general state of the patients with the development of purulent septic complications with mortality level.

Highly accurate laser optoelectronic instruments with automatic adjustment systems are considered, which provide high accuracy in the angular adjustment of the axes of their receiving-transmitting channels. A procedure for designing a high-precision parallel-transfer device, based on two pairs of pentaprisms, necessary to ensure the operation of this system, is investigated. The effect of the system for measuring the angular coordinates of the radiation beam on the operating stability of the instruments is considered. A detailed analysis of the probability of signal loss due to the effect of vibrations on the system is presented.

The objective of the present study was to survey epidemiology of oto- and rhinosinusogenic intracranial complications that are currently diagnosed at the territory of the Russian Federation. The work was based on the analysis of the official statistical reports together with the data obtained from the chief specialists responsible for the otorhinolaryngological services in 32 subjects of the Russian Federation during the period from 2009 to 2014. It was shown that the state of the otorhinolaryngological service in the period covered by the study was characterized by the reduction in the number of beds available for the patients presenting with ENT pathology by 14.0% and the lowering of the hospitalization rate for the general population by 6.3%. The frequency of oto- and rhinosinusogenic intracranial complications among the patients hospitalized to occupy the beds intended for the care of the patients suffering from ENT diseases was estimated at 0.03% and intrahospital lethality at 21.2%. The prevalence of pyogenic intracranial complications associated with the inflammatyory pathology affecting ENT was 0.61 per 100.000 population per year, with the mortality rate amounting to 0.17 fatal outcomes per 100.000 population per year. The study revealed significant correlation of the principal medico-statistical characteristics of high-frequency oscillatory ventilation (HFOV)---?? between themselves and with the parameters of ENT morbidity and activities of the otorhinolaryngological services at the territory of a given administrative territory. It is concluded that the improvement of the quality of healthcare for the population presenting with intracranial complications and inflammatory ENT diseases is possible only on the baseis of the combined and interdisciplinary approach to the solution of the problem.Цель исследования - изучение эпидемиологии ото- и риносинусогенных внутричерепных осложнений на территории России в настоящее время. Материалом для исследования послужили официальные статистические данные, а также сведения, полученные от главных специалистов-оториноларингологов 32 субъектов РФ за период с 2009 по 2014 г. Состояние ЛОР-службы обследуемых субъектов за указанный период характеризуется снижением обеспеченности населения ЛОР-койками на 14,0% и уровня госпитализации населения на 6,3%. Частота ото- и риносинусогенных внутричерепных осложнений среди пациентов, госпитализированных на ЛОР-койки, составила 0,03%, а больничная летальность - 21,2%. Заболеваемость гнойными внутричерепными осложнениями при воспалительной патологии ЛОР-органов составила 0,61 на 100 000 населения в год, а смертность - 0,17 летальных исходов на 100 000 населения в год. Выявлена достоверная корреляционная связь основных медико-статистических показателей ВЧО между собой, а также с климатическими, демографическими факторами и показателями ЛОР-заболеваемости и деятельности ЛОР-службы на территории субъекта. Сделан вывод, что повышение качества медицинской помощи пациентам с внутричерепными осложнениями при воспалительных заболеваниях ЛОР-органов возможно только при комплексном и междисциплинарном подходе к решению проблемы.

The objective was to study changes of an articulate surface (AS) of coxofemoral joints (CFJ) at patients with osteoarthrosis (OА), using СТ Methods. The group of patients (92 joints), suffering bilateral OА 2nd and 3rd radiological stage was tested by СТ. The width of AS in front, anteromedial, posterolateral, back sides was measured; thus joints of all patients have been preliminary divided in two groups: group (A) with uniform narrowing of an articulate surface and group (B) with nonuniform narrowing AS. Comparison of sizes and areas of joint space in different parts was performed.

[This essay attempts to analize Zamiatin's We as an aesthetic whole in which, pace Yuri Tynianov, antiutopia is organically combined with “a fantastic adventure novel.” With this aim in mind We is read not only in its literary context but also in a historical-poetologic perspective, ranging from Hellenistic love/adventure novels to Andrei Belyi's Silver Dove. Following in Belyi's footsteps, Zamiatin develops a Dionysian theme according to the interpretation proposed by Viacheslav Ivanov's interpretation (his conception of the divine unity of existence), making the myth of Dionysus the subject of an aesthetic experiment in the tradition of Mennipian satire. The author of We, to what extent the protagonist-narrator can be associated with his creator, is concerned with the fate of “the whole” not less than with the fate of individual. He is confronted with an unresolved conflict in terms of atheistic consciousness, bearing not only personal and socio-political consequences, but ontological as well., This essay attempts to analize Zamiatin's We as an aesthetic whole in which, pace Yuri Tynianov, antiutopia is organically combined with “a fantastic adventure novel.” With this aim in mind We is read not only in its literary context but also in a historical-poetologic perspective, ranging from Hellenistic love/adventure novels to Andrei Belyi's Silver Dove. Following in Belyi's footsteps, Zamiatin develops a Dionysian theme according to the interpretation proposed by Viacheslav Ivanov's interpretation (his conception of the divine unity of existence), making the myth of Dionysus the subject of an aesthetic experiment in the tradition of Mennipian satire. The author of We, to what extent the protagonist-narrator can be associated with his creator, is concerned with the fate of “the whole” not less than with the fate of individual. He is confronted with an unresolved conflict in terms of atheistic consciousness, bearing not only personal and socio-political consequences, but ontological as well.]

It is known that the high energy $(> 100\,\text{MeV})$ emission of gamma-ray bursts is delayed with respect to the low energy emission. However, the dependence of light curves on energy has not been studied for the high energy bands. In this paper we consider the bursts observed by Fermi LAT from 2008 August 4 to 2011 August 1, for which at least $10$ photons were observed with the energy greater than $1\,\text{GeV}$. These include $4$ bursts: GRB 080916C, GRB 090510, GRB 090902B, and GRB 090926A. We use the Kolmogorov-Smirnov test to compare the light curves in the two bands, $100\,\text{MeV} < E < 1\,\text{GeV}$ and $E > 1\,\text{GeV}$. For GRB 080916C and GRB 090510 the light curves in the two bands are statistically compatible. However, for GRB 090926A, the higher-energy light curve is stretched compared to the lower-energy one with a statistical significance of $3.3 ��$ and, for GRB 090902B, on the contrary, the lower-energy curve is stretched with $2.3 ��$ significance. We argue that the observed diversity of stretching factors may be explained in a simple geometrical model. The model assumes that the jet opening angle depends on the emission energy in a way that the most energetic photons are radiated near the axis of the jet. All the bursts are considered equivalent in their rest frames and the observed light curves differ only due to different redshifts and view directions. The model conforms to the total burst energy constraint and matches the Fermi LAT observations of the fraction of GRBs visible in $100\,\text{MeV} < E < 1\,\text{GeV}$ band, which may be observed at higher energies. The model predicts the distribution of observable stretching factors, which may be tested in the future data. Finally, we propose a method to estimate observer's off-axis angle based on the stretching factor and the fraction of the high-energy photons., 23 pages, 8 figures

First principles calculations have been performed to investigate ground state properties of monoperiodic TiO2 and SrTiO3 single-walled nanotubes containing extrinsic point defects. The hybrid exchange-correlation functionals B3LYP and B3PW within the framework of density functional theory have been applied to calculations for nanotubes with the following substitution impurities: CO, NO, SO, and FeTi. Variations in the formation energies obtained for equilibrium defective nanostructures allow us to predict the most stable compositions, irrespectively of the changes in growth conditions. Changes in the electronic structure show mid-gap states induced by defects.

To predict the growth mechanism of carbon nanotubes (CNT) upon nickel catalyst, we have performed a series of large-scale DFT-LCAO interface calculations. When using the CVD method for CNT synthesis, carbon adatoms appear upon the nickel catalyst surface due to dissociation of carbon-hydrogen molecules (

This study was designed to obtain morpho-functional characteristics of nasal mucosa associated with septal deformation. It has demonstrated disturbances in the mucociluary transport, compromised mucosal immunity, and morphological changes in the nasal cavity.

An equation is found that is the second in the hierarchy of higher order equations connected with Dym's equation; equations on the scattering data are introduced; its (3+1)-dimensional analogue is considered which admits a Lax representation with the same operator L and an operator A including differentiation with respect to the additional variables; the presence of a countable family of integrable discretizations of the second Korteweg-de Vries equation is demonstrated.

We present the results of ab initio calculations on magnetic and electronic structures of La1�xSrxMnO3 at low doping, x =1/8. Using the B3LYP hybrid exchange-correlation functional within the framework of densityfunctional theory, we predict a ferromagnetic ground state for La0.875Sr0.125MnO3 in both the low-temperature orthorhombic and the high-temperature pseudocubic phases. This is in contrast to its parent compound LaMnO3, for which we find in agreement with experiment the layered antiferromagnetic state to be the most stable one. The calculated density of states and bond population analysis suggest a tendency of formation of half-metallic spin states in the band gap of both structures.

The energy level positions in the optical gap and atomic geometry for the Fe4+ impurity substituting for a host Ti atom in SrTiO3 are calculated using the Unrestricted Hartree-Fock (UHF) method and supercells containing up to 320 atoms. In agreement with experiment, the high spin (S = 2) state is much lower in energy than the zero-spin state. The energy level positions strongly depend on the asymmetric displacements of six nearest O ions which is a combination of the Jahn-Teller and breathing modes. A considerable covalent bonding between the Fe ion and four nearest O ions takes place. We predict a strong dependence of optical absorption energies on the crystal compression or internal tension, e.g. in perovskite solid solutions.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The ground of architecture and description of WinALT simulating system are given in the paper. The main purpose of graphical WinALT interface is to visualize the model construction and execution. WinALT language is suitable for representation of versatile classes of fine-grain algorithms and structures. The system has a comprehensive set of tools for user extensions.

A procedure for architectural design of fine-grained parallel devices composed from blocks is presented. The procedure is performed with a computer simulation system ALT.