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Spin waves are an emerging alternative to electrical signals for high-speed computing. One approach to realizing spin-wave computing devices is to make use of the diffraction and interference of spin waves in a magnetic thin film. This new class of device requires spin wave transducers that operate across a relatively wide bandwidth. Coplanar-waveguide-based transducers would typically be unsuitable for this application due to their comb-like frequency response. Our simulations show that if the coplanar waveguide is placed to the side of the edge of a magnetic film, the frequency response is greatly improved at the expense of peak transducer efficiency. We also found that the coplanar waveguide on top of the film with an etched gap in the film to the side of the waveguide can be a more efficient transducer for shorter decay lengths.

The anisotropy of the conductivity and the shape of the I–V characteristics for a two-dimensional quantum superlattice with the nonharmonic electron dispersion law are investigated for different directions of the current and field applied to the structure relative to the superlattice axes. The anisotropy of the characteristics and the conditions for the occurrence of multivalue I–V characteristics in different current flow modes are discussed. It is shown that the deviation of the electron dispersion law in a two-dimensional quantum superlattice from the harmonic one in a strong dc electric field noticeably affects the shape of the I–V characteristic of a two-dimensional quantum superlattice. Several current peaks in a strong field are caused by both mixing of the current lines for directions orthogonal to the applied field and electron transport over Stark-ladder levels formed in different miniband valleys.

Enthalpies of formation (ΔfH∘) for 31 radicals of the series of substituted Ph-N∙H and Ph-N∙-Ph were determined for the first time. The calculations were based on the dissociation energies of N-H bonds in the corresponding molecules and their ΔfH∘. A quantitative “structure—enthalpy of formation” correlation was established for these radicals within the framework of the additive-group approach. The ΔfH∘ of radicals were analyzed and the most reliable values were suggested.

Irrigation uniformity in a semi-arid climate remains one of the main factors of water use efficiency (WUE) regardless of the level of agronomic advance, since over- and under-watered parts of the field represent wasted water or wasted yield at a given irrigation dose. The aim of this study was to analyze the underlying reasons for low WUE of linear move irrigators (LMI), detected by remotely sensed crop biomass maps in the Hula Valley, Israel. Head and tail towers were equipped with high-accuracy GNSS devices, recording their movements at 0.015 m accuracy. Periodic aerial surveys, run with multi-copter mounted visible and thermal cameras, showed stable and persistent over- and under-irrigation spatial patterns. Tower movement analysis revealed a “zigzag” pattern, where each tower lags behind and then catches up intermittently; over-irrigating during lags, under-irrigating during runs at the same spatial pattern over time, explaining the biomass variability. Deviations from the average at head and tail edge towers were in the 45–50% range of over-watering and the − 30% range of under-watering, and around ± 13%, at the mid part of the field. Yield sampling found 15% (pF > 0.069) yield loss. Sunken and winding wheel tracks observed in the field may have caused that movement pattern. Low WUE means waste of water that has a severe economic impact, especially in water scarce regions. Since water shortages are expected with climate change in many agricultural regions around the world, it is imperative to improve LMI machine movement uniformity, or to enable compensating irrigation control in order to solve water waste issues.

An $$n$$ -dimensional economic model is considered that has a Cobb–Douglas production function on the infinite planning horizon such that the utility function is an integral-type functional with a discount and a logarithm-type integrant. It is assumed that all of the model’s amortization factors are equal to one another. The constructed optimum control contains $$n-1$$ special segments that are described analytically. A special sweep procedure for consecutively solving two Cauchy problems on each segment is developed to find moments of switching between segments and the shape of the optimum trajectory. On the last segment, the optimum trajectory lies along a special ray; from the viewpoint of economy, this ray can be interpreted as the mode of equilibrium growth. A Pontrjagin maximum-principle problem with a special transversality condition is used to construct the optimum solution. Optimality is confirmed using the Kiselev theorem on sufficient conditions. Moving to problems of large dimensions considerably increases the number of technical difficulties. The description of the optimality verification procedure is therefore presented in detail for methodological reasons.

The impacts of climate change on the food system are a key concern for societies and policy makers globally. Assessments of the biophysical impacts of crop productivity show modest but uncertain impacts. But crop growth is not the only factor that matters for the food production. Climate impacts on the labour force through increased heat stress also need to be considered. Here, we provide projections for the integrated climate-induced impacts on crop yields and worker productivity on the agro-economy in a global multi-sector economic model. Biophysical impacts are derived from a multi-model ensemble, which is based on a combination of climate and crop models, and the economic analysis is conducted for different socio-economic pathways. This framework allows for a comprehensive assessment of biophysical and socio-economic risks, and outlines rapid risk increases for high-warming scenarios. Considering heat effects on labour productivity, regional production costs could increase by up to 10 percentage points or more in vulnerable tropical regions such as South and South-East Asia, and Africa. Heat stress effects on labour might offset potential benefits through productivity gains due to the carbon dioxide fertilisation effect. Agricultural adaptation through increased mechanisation might allow to alleviate some of the negative heat stress effects under optimistic scenarios of socio-economic development. Our results highlight the vulnerability of the food system to climate change impacts through multiple impact channels. Overall, we find a consistently negative impact of future climate change on crop production when accounting for worker productivity next to crop yields.

An identity is derived expressing Schur functions as sums over products of pairs of Schur $Q$-functions, generalizing previously known special cases. This is shown to follow from their representations as vacuum expectation values (VEV's) of products of either charged or neutral fermionic creation and annihilation operators, Wick's theorem and a factorization identity for VEV's of products of two mutually anticommuting sets of neutral fermionic operators., 17 pages. Typos corrected. Title word order changed. References updated

Based on the combination of molecular and morphological data, we herein report the second known finding of the xenodermid snake species Parafimbrios vietnamensis Ziegler, Ngo, Pham, Nguyen, Le & Nguyen, 2018. The male individual was found in the Yen Bai Province of northwestern Vietnam, more than 200 km from the type locality in Lai Chau Province. Genetic divergence between the newly-collected male and the holotype was low (1.7%), and is in agreement with morphological data that supports that they are conspecific. We give a detailed description of the morphological characters and coloration of the new record and provide an expanded diagnosis of P. vietnamensis. Parafimbrios is a poorly-understood genus, and our recent discovery brings the total number of known specimens of the genus to nine, 1/3 of them having been found in Vietnam (one specimen of P. lao and now two specimens of P. vietnamensis).

The article discusses the proposed algorithm and method for determining the optimal grinding conditions for linear bearing guides of low rigidity, which ensure meeting the specified requirements for the quality of the processed surface (surface roughness parameter Ra, no grinding burns and surface flatness tolerance) at maximum process productivity. Input factors (grinding wheel hardness, radial feed, table feed speed) are parameters for optimizing the grinding process. Mathematical models of the output factors are designed to limit the range of acceptable values of the optimization parameters. Processing performance was chosen as the target function. Optimization of parameters within the range of permissible values is carried out on the basis of ensuring the maximum productivity of the process. The required flatness tolerance is provided at the second stage of mode optimization by limiting the value of the maximum elastic deformation. The cutting forces, the magnetic field attraction of the machine table and the bending stiffness of the workpiece are the variable parameters. Mathematical models for determination of maximum elastic deformation of prismatic workpieces when fixing and machining are presented. The conditions for ensuring a given workpiece surface flatness tolerance are determined, taking into account the elastic deformation of a prismatic workpiece of low rigidity under the effects of the magnetic field of the machine tool and the radial component of the grinding force.

General trends of the current stage of development of the world and domestic economies confirm the most important trends of financial systems of the leading countries, including Ukraine. Among them, it is advisable to highlight the following: financial inclusion, formation of an unassailable reputation by financial institutions, reducing the volume of shadow banking, increasing the level of the population’s financial literacy, developing financial technologies, and deepening the financial system. All of this involves increasing the size of financial assets in relation to the size of the economy based on the GDP indicator. Based on the results of generalizing the approaches of scientists to the list of determining factors affecting the development of the country’s financial system, the key role of the level of financial literacy of the population was established. The article presents the total index of financial literacy of the population of individual countries of Europe and the world based on the index components. The development of the financial system in all these areas creates conditions for a gradual transition to the development of a new quality financial ecosystem. The article proposes a definition of the financial ecosystem in the context of established hybrid of real and digital space based on the integration of financial institutions as key players with technology companies, public service providers and other participants. To ensure development, the advantages and disadvantages are specified based on the results of the SWOT analysis, which allowed to systematize the strengths and weaknesses, as well as the opportunities and threats of the financial ecosystem development. Based on the results of the analysis, four basic strategies for restructuring the financial system were developed, which are the basis for proposals for the development of the financial ecosystem and changing the business models of functioning of its subjects in Ukraine.

Analysis of the frequency of karyotypes and chromosomal rearrangements in the distributional ranges of four metacentric races of Sorex araneus Linnaeus, 1758 has revealed features that are not typical for polymorphic populations of this species. The frequency of the acrocentric karyotype and heterozygotes for fusion of acrocentric chromosomes turned out to be significantly higher than expected in case of random crossing. As an explanation for the unusual polymorphism, it has been suggested that metacentric races may hybridize with acrocentric populations that remained from the ancient chromosomal form.

Рассматривается задача обращения линейного квантования, задаваемого интегральным преобразованием, связывающим матрицу квантового оператора с его классическим символом. Для произвольного линейного квантования построены уравнения эволюции матрицы плотности и функции Вигнера. Показано, что только для квантования Вейля уравнение эволюции функции Вигнера не содержит источника квазивероятности, что выделяет это квантование как единственное физически адекватное в рассматриваемом классе. Приведен пример точного стационарного решения для функции Вигнера гармонического осциллятора при произвольном линейном квантовании, и построена последовательность квантований, аппроксимирующих квантование Вейля и сходящихся к нему в слабом смысле так, что функция Вигнера остается положительно определенной.

In 2016, an outbreak of anthrax killing thousands of reindeer and affecting dozens of humans occurred on the Yamal peninsula, Northwest Siberia, after 70 years of epidemiological situation without outbreaks. The trigger of the outbreak has been ascribed to the activation of spores due to permafrost thaw that was accelerated during the summer heat wave. The focus of our study is on the dynamics of local environmental factors in connection with the observed anthrax revival. We show that permafrost was thawing rapidly for already 6 years before the outbreak. During 2011–2016, relatively warm years were followed by cold years with a thick snow cover, preventing freezing of the soil. Furthermore, the spread of anthrax was likely intensified by an extremely dry summer of 2016. Concurrent with the long-term decreasing trend in the regional annual precipitation, the rainfall in July 2016 was less than 10% of its 30-year mean value. We conclude that epidemiological situation of anthrax in the previously contaminated Arctic regions requires monitoring of climatic factors such as warming and precipitation extremes. Supplementary Information The online version contains supplementary material available at 10.1007/s10393-021-01549-5.

The results of the development of a current sensor with galvanic isolation based on the anisotropic magnetoresistive effect without magnetic flux concentrators (MFCs) and two variants of MFC designs are presented. The influence of the MFCs on the electrophysical characteristics of the sensor is studied, as well as their role in the displacement of the conductor relative to the sensitive element. The developed current sensor provides the control of both direct and alternating electric currents with a frequency of up to 210 kHz, starting from 0.5 mA, without breaking the conductor. The range of the measured currents is up to ±24 A, with a conversion factor of up to 4 V/A, and the current consumption does not exceed 30 mA in the temperature range from −60 °C to +125 °C.

SummaryWe studied the applicability of a gradient-boosting machine-learning (ML) algorithm for forecasting of oil and total liquid production after hydraulic fracturing (HF). A thorough raw data study with data preprocessing algorithms was provided. The data set included 10 oil fields with more than 2,000 HF events. Each event has been characterized by well coordinates, geology, transport and storage properties, depths, and oil/liquid rates before fracturing for target and neighboring wells. Each ML model has been trained to predict monthly production rates right after fracturing and when the flows are stabilized. The gradient-boosting method justified its choice with R2 being approximately 0.7 to 0.8 on the test set for oil/total liquid production after HF. The developed ML prediction model does not require preliminary numerical simulations of a future HF design. The applied algorithm could be used as a new approach for HF candidate selection based on the real-time state of the field.

―A new anion-deficient Sr2.4Dy0.6Co2O7‒δ (δ = 0.33–1.1) perovskite phase with a structure of the A3B2O7 Raddlesden‒Popper homologous series has been obtained by the solid-state synthesis in the reducing/oxidizing atmosphere and its structural characterization has been performed by the Rietveld refinement of the X-ray powder diffraction data. It has been stablished that the Sr2.4Dy0.6Co2O7‒δ compound (sp. gr. I4/mmm) has parameters of a = b = 3.8526(1) and c = 19.9431(7) A in the reduced form (δ = 1.1) and a = b = 3.8086(1) and c = 19.9190(6) A in the oxidized form (δ ≈ 0.33) and oxygen vacancies occupy mainly the sites linking CoO5 polyhedra inside two perovskite layers. It has been established using differential scanning calorimetry and thermogravimetry that, at T

The results of speckle interferometric measurements of binary stars performed during June, 2016 with the 2.1 m telescope at the Observatorio Astronómico Nacional at SPM (México) are given. We report 480 astrometric measurements of 468 double stars systems. The measured angular separations ρ range from 0’’.091 to 5’’.93. Most of the observed pairs (414 out of 468) are close double stars having separations of ρ ≤ 1’’. We confirm as double stars 59 targets and we found 3 new pairs with separation of less than 1’’. Finally, we show that the high resolution autocorrelation function in polar coordinates allows to easily recover astrometric parameters even in the presence of strong telescope aberrations.

A preparation of peat humic acids modified by electrochemical treatment in an alkaline medium on iron electrodes was obtained. The effect of the electrochemical treatment on the dispersed composition of the particles of humic substances was determined using dynamic light scattering (quantum correlation spectroscopy). It was found that humic compounds in solution predominantly occur in the form of agglomerates (130–6000 nm), the dispersed composition of which becomes more homogeneous upon electrochemical treatment, and the ability for associative interactions decreases.

Within the multielectron model of magnetic insulator with two different spin terms at each cation and spin crossover under high pressure we have studied dynamics of a sudden excited non equilibrium spin state. We obtain the different relaxation of the magnetization, high spin/low spin occupation numbers, and the metal-oxygen bond length for different values of the external pressure. For each pressure-temperature values stationary state agrees to the mean field phase diagrams. We found the long living oscillations of magnetization for the high spin ground state at small pressure. Close to crossover pressure the smooth relaxation is accompanied with a set of sharp strongly non linear oscillations of magnetization and HS/LS occupation numbers that are accompanied by the Franck–Condon resonances.

Elimination of significant risks in nuclear power production is at the present stage a necessity and goal-setting that determines its development in the near future. Of particular importance is the problem of maximum credibility and convincingly substantiated stability of nuclear power plants against severe accidents. The lack of clear logic, transparency and guarantees in the reliability of the announced nuclear safety significantly hinders its development, unnecessarily overcomplicating expensive technical solutions, thereby weakening the competitiveness of nuclear power. The originally proposed Concept of Inherent Safety set the task of solving the above problems; however, its specific content has not been explicitly presented so far, which allows many competitors to use its terminology to promote projects that are not directly related to the ‘spirit and letter’ of Inherent Safety. This paper is intended to fill this gap. The authors also discuss the conditions for the generation and development of new self-protection means for innovative nuclear reactors as well as the phenomenological and technical aspects for their implementation based on the deterministic formalism.

This paper presents a techno-economic assessment of a hybrid solar-geothermal power plant that is modelled taking into account the available geothermal and solar energy resources at the Tendaho-1 (Dubti) geothermal field in Ethiopia. The hybrid power plant combines a single-flash geothermal power plant with a parabolic trough solar thermal plant to increase the energy level of geothermal steam. The geothermal fluid from one of the production wells at the geothermal site and the direct normal solar irradiance prevailing in the area offer the primary sources of energy used in the modelling. A thermodynamic analysis based on the principles of mass and energy conservation and a figure of merit analysis that allows evaluating the energy and economic performance of the hybrid power plant were performed. The technical and economic efficiency assessment was performed by comparing the performances of the hybrid power plant with a power system consisting of stand-alone geothermal and solar power plants. Results of the techno-economic assessment showed that for the same amount of energy inputs, depending on the available thermal energy storage capacity, a hybrid power plant generates up to 10.4% more electricity than a power system of two stand-alone power plants while generating a higher net present value at a lower cost of generation. In addition, the hybrid power plants with and without thermal storage system exhibit an economic figure of merit values of 2.62 and 3.42, i.e. the cost of solar resource per kWh of electricity in the hybrid energy system is reduced by 70.5% and 61.5%, respectively.

Metal structures, pipelines and dies are used for a long time wear out and deteriorate. At the end of the service life it is necessary to repair or replace the metal component. The article discusses the method of applying nickel super-alloy Inconel 625 by direct laser deposition on high-alloy austenitic Mn-Cr steel. The article discusses the method of applying nickel super-alloy Inconel 625 by direct laser deposition on high-alloy austenitic Mn-Cr steel. Inconel 625 alloy is used as a buffer layer or repair material. But there is a high probability of cracks in the cladding material and the substrate material when the DLD method is used. One of the frequent causes of these cracks is high tensile stresses and oxides. To eliminate defects, the substrate was heated with resistive heaters to 400 °C. The result was a defect-free adhesion of the cladding material and the substrate. The hardness of the substrate before and after heating has not changed (312 HV 0,5/10). After heating the hardness of the substrate in the heat-affected zone decreased by 14% and was equal to 267 HV 0,5/10. The hardness of the cladding decreased by 12% and was equal to 230 HV 0,5/10.

We have studied the process underlying the preparation of chromium powders via the magnesium vapor reduction of the Cr2O3 and MgCr2O4 chromium oxide compounds in the temperature range from 700 to 800°C and residual argon pressures in the reactor from 5 to 20 kPa. The chromium powders obtained by reducing the MgCr2O4 chromite have a specific surface area at a level of 34 m2/g and are characterized by a mesoporous structure.

The reduction of TiO2 and CaTiO3 in a mixture with calcium has been studied in an argon atmosphere and vacuum at temperatures in the range 1023–1123 K. The adiabatic temperature of the reduction reactions involved has been calculated as a function of the excess of calcium in the starting mixture and its initial temperature. The presence of a thin CaCl2 film on calcium particles and the use of calcium titanate as a precursor have been shown to increase the reduction rate. The use of a CaTiO3 precursor and CaCl2-activated calcium has made it possible to obtain titanium powders containing 0.5 wt % oxygen and having a specific surface area of 1.2 m2/g via reduction at a temperature of 1073 K for 6 h.

In this paper the investigation of the structure of network graph is presented. The social network between the Russian towns is considered. It is shown, that the distribution of vertex powers is uniform. As a consequence there is a high dimension region with whole connection. The probability of special sub-graphs is estimated. The Liouville equation is used for modeling of the graph structure evolution.

The paper gives a solution to one of the problems of the analytical approximate method for one class first order nonlinear differential equations with moving singular points in the real domain. The considered equation in the general case is not solvable in quadratures and has movable singular points of the algebraic type. This circumstance requires the solution of a number of mathematical problems. Previously, the authors have solved the problem of the influence of a moving point perturbation on the analytical approximate solution. This solution was based on the classical approach and, at the same time, the area of application of the analytic approximate solution shrank in comparison with the area obtained in the proved theorem of existence and uniqueness of the solution. Therefore, the paper proposes a new research technology based on the elements of differential calculus. This approach allows to obtain exact boundaries for an approximate analytical solution in the vicinity of a moving singular point. New a priori estimates are obtained for the analytical approximate solution of the considered class of equations well in accordance with the known ones for the common area of action. These results complement the previously obtained ones, with the scope of the analytical approximate solution in the vicinity of the movable singular point being significantly expanded. These estimates are consistent with the theoretical positions, as evidenced by the experiments carried out with a non-linear differential equation having the exact solution. A technology for optimizing a priori error estimates using a posteriori estimates is provided. The series with negative fractional powers are used.

The paper analyzes a mathematical model for calculating the composition and size of portions of the optimal menu in accordance with the recommendations of the Ministry of Health, depending on the planning horizon. The questions of the accuracy of the solution depending on the accuracy of the input data are considered. Spectral portraits of diurnal and averaged nutrient matrices are studied. It is shown, that despite the poor conditionality of the daily matrices, the result of weekly averaging allows us to perform calculations at a sufficient level of accuracy.

The kinetics of cesium and strontium sorption by natural clinoptilolite and its ferrocyanide-modified analogs, NPF-Cl and NPF-Cl (Ca-form), from solutions of various compositions containing 100 mg L–1 sorbate was studied, and the texture and porosity of the sorbent samples before and after the sorption of cesium and strontium were determined. The sorption process occurs in three-stages and is limited by a heterogeneous ion exchange reaction (HIOR) on the ferrocyanide phase located on the outer surface of clinoptilolite and in its macropores, internal diffusion of cesium and strontium into sorbent granule, and precipitation of ferrocyanide phases of complex composition in small mesopores and micropores of sorbents. The HIOR and precipitation occur with involvement of solution components (sodium, calcium, and iron). Sorption of cesium and strontium is accompanied by a significant change in the texture and porosity of the sorbents.

In this paper, the authors suggested a finite element approach to the simulation of mechanical properties of functionally graded materials (FGM) using a multilinear plastic material model. The approach was used to simulate tensile test experiments on the homogeneous specimens manufactured at two laser power regimes and composite specimens based on the materials considered. We showed a correlation between the simulation results and the experiment. We studied the mechanical effect of geometry and size of inserts in the composite specimens and determined that changing the size and geometry of the inserts can modify the mechanical characteristics of the specimen. We found that the multilinear plastic material model provides the highest level of agreement between simulation and experimental results and, unlike the bilinear model, is more comprehensive.

The arbitrary linear quantization is considered for definition of Wigner function. The evolution equation of this function is derived with the use of inversion of linear quantization kernel. In general case the Moyal equation depends on the characteristic function of quantization. It is shown that only for Weyl quantization this equation does not consist the source of quasi-probability. The stationary solutions of Moyal equation are constructed for an arbitrary linear quantization of a harmonic oscillator. The case of anharmonic oscillator is presented as a practical example of quantum system model in the so-called post-newtonian approximation. This model exhibits the intersection effect between quantization dependences of Hamiltonian and Wigner function.

A complete annotated list of marine, brackish-water, and freshwater ichthyofauna of Sakhalin Island and the adjacent southern part of the Sea of ​​Okhotsk is provided for the first time in the entire history of the study of the fish population. It is based on a critical analysis of the literature data for the last 200 years, collection materials, and the results of our own long-term studies. The list includes 600 species in 4 classes, 44 orders, 17 suborders, 129 families, 50 subfamilies, and 312 genera. It presents both English and Latin (scientific) names, information on the ranges in the World Ocean and distribution within Sakhalin waters, and data on the conservation status, commercial importance, and abundance. For a number of species, the list also provides information on collection specimens, confirming their presence within the studied water area. For all species, the current ranges and taxonomic status are specified according to the new data, if any. The so-called controversial taxa are discussed. The first part provides brief information about the history of the study of the Sakhalin ichthyofauna, the geographical and oceanological characteristics of the study area, as well as the first 118 species of the annotated list belonging to 79 genera, 42 families and 20 orders in 4 classes.

Nonstoichiometric silicon nitride SiNx is a promising material for developing a new generation of high-speed, reliable flash memory device based on the resistive effect. The advantage of silicon nitride over other dielectrics is its compatibility with the silicon technology. In the present work, a silicon nitride-based memristor deposited by the plasma-enhanced chemical vapor deposition method was studied. To develop a memristor based on silicon nitride, it is necessary to understand the charge transport mechanisms in all states. In the present work, it was established that the charge transport in high-resistance states is not described by the Frenkel effect model of Coulomb isolated trap ionization, Hill–Adachi model of overlapping Coulomb potentials, Makram–Ebeid and Lannoo model of multiphonon isolated trap ionization, Nasyrov–Gritsenko model of phonon-assisted tunneling between traps, Shklovskii–Efros percolation model, Schottky model and the thermally assisted tunneling mechanisms. It is established that, in the initial state, low-resistance state, intermediate-resistance state and high-resistance state, the charge transport in the forming-free SiNx-based memristor is described by the space charge limited current model. The trap parameters responsible for the charge transport in various memristor states are determined.

Active construction of new roads and other linear structures requires new techniques for the natural hazard assessment. These techniques can involve both stochastic modeling and remote sensing data (RSD). First, the dynamics of thermokarst appearance along an unpaved road (winter road) was analyzed. Then a probabilistic model of the thermokarst morphological pattern was developed for the area in the vicinity of a linear structure, a road in particular. The model operates with initial assumptions based on the physical parameters of thermokarst development and includes relations for estimating the distribution of morphometric dimensions of thermokarst depressions (ponds). The model was empirically tested for the study area, which represented a site with an unpaved road located in West Siberia region. To verify the model, we calculated the correlation coefficient values for the length of the focus projections on the linear structure and the perpendicular axis and compared the empirical distribution of the projections with the theoretical lognormal distribution using the Pearson’s criterion. The proposed model assumptions appeared to be valid for the study area, which makes it possible to proceed to the problem of probabilistic impact risk assessment to a linear structure by foci of human-induced thermokarst.

We report here the first evidence for the interaction of poly(ethylene glycol) (PEG) with hyaluronan (HA) in aqueous solutions. PEG-HA complexes (Kapp = 45,000 ± 8000 M-1) contained about 3.3 ± 0.1 of ethylene glycol units per disaccharide of HA. The carboxyl of the D-glucuronic acid and the amide of the N-acetyl-D-glucosamine did not participate in PEG binding. Similar experiments performed with dextran and monosaccharides showed that multiple free primary hydroxyls regularly distributed along the polysaccharide chain are necessary for PEG binding. Another novelty of our study is contraction of HA upon PEG binding. The effect was observed with HA in solution or adsorbed on positively charged liposomes. The thickness of the HA layer on the liposomes decreased 2-fold upon PEG addition. HA compaction induced by PEG may underlie the changes in the plasma membrane properties and resealing of mechanical injuries induced by Pluronics.

Little is known about the distribution of dormouse species in the Middle Volga region. The habitats of the Edible Dormouse Glis glis L. and the Hazel Dormouse Muscardinus avellanarius L. are fragmented and mainly lost in the agricultural landscape of the right bank of the Volga River and in the coniferous forests of the right bank of the Lower Oka River in Nizhny Novgorod oblast. New data are given of features of the habitats of two sympatric dormouse species from a patch of a lime–oak forest surrounded by coniferous forests. Within the area studied, 80 wooden nestboxes were put up in places with well-connected tree canopies and well-developed understory. Over the three years of our study (2016–2018), preliminary data were obtained on the dynamics of nestbox use and the relative abundance and reproduction of both dormouse species. The patch of the lime–oak forest with an area of approximately 20 ha is divided into two parts by a road and a 50 m-wide glade. Both parts did not differ in vegetation, but the Edible Dormouse was found only in the southern part. The Hazel Dormouse was found throughout the whole lime–oak patch, except for woodplot no. 1 (1.5 ha), which was occupied by the Edible Dormice with a high density. On the basis of the data obtained, management actions are suggested to raise the level of connectivity and immigration in the population of isolated broad-leaved patches in coniferous forests, in particular, to develop a network of “key habitats.”

By the example of the Dy0.2Sr0.8CoO3-δ compound undergoing an order–disorder phase transition with increasing temperature, we demonstrate a significant dependence of the kinetic properties on the morphology of the internal spatially inhomogeneous structure, which forms in the sample depending on the rate of its transition from the high-temperature disordered cubic phase to the ground tetragonal ordered phase upon cooling. The results of transmission electron microscopy visualization of the spatially inhomogeneous state in the Dy0.2Sr0.8CoO3-δ ceramic samples are presented and compared with the X-ray diffraction data.

The work juxtaposes electron density distributions in N,N-dimethylaniline, its three parasubstituted derivatives, two orthosubstituted derivatives of benzoic acid, 2-[4-[(dimethylamino)-phenyl]diazenil]benzoic acid (methyl red), and benzene. Intramolecular weak interactions C⋯H, H⋯H, and O⋯N and the rings they form are considered within the “quantum theory of atoms in molecules” (QTAIM). The characteristics of QTAIM bonds at critical points are found. The stability of rings is estimated; relative stability of C⋯H and O⋯N bonds stabilizing spatial molecular configuration in methyl red is demonstrated.

Calcium alkali metal (potassium and sodium) double and triple phosphates have been synthesized in different ways. Was for the first time used reaction sintering to produce ceramics based on calcium alkali metal mixed phosphates and investigated the densification behavior of mixed phosphate-based multiphase materials during sintering by this method. Was presented the microstructure of polished surfaces of sintered samples differing in phase composition and determined the density of ceramics prepared using reaction mixtures differing in composition. The effect of reaction sintering on the porosity of the ceramics has been assessed. Using stereolithographic printing and reaction sintering, was produced macroporous mixed calcium phosphate-based ceramic implants. Their compressive strength has been determined to be 0.78 ± 0.21 MPa for two-phase samples and 1.02 ± 0.13 MPa for three-phase samples.

Subject. Escalating international tensions make nuclear attacks more possible, such as a high-altitude nuclear explosion, which mainly threatens with the electromagnetic pulse. It can destroy modern electrotechnical equipment, especially if it is fitted with microprocessor equipment. Objectives. The study presents considerations on the resilience of infrastructure systems provided they are exposed to the electromagnetic pulse of a high-altitude nuclear explosion. Methods. The study is based on methods of systematization, analysis and comparison. Results. We suggest writing infrastructure system requirements into all regulatory, legislative and legal documents on the energy security and electromagnetic compatibility in case of the electromagnetic pulse of a nuclear explosion. The issue can possible be solved as professionals gather sufficient theoretical, experimental and practical data. We provide the rationale for using properly upgraded testing facilities owned by the Russian Federal Nuclear Centre of Rosatom, and making a special task-force, which could be deal with ensuring the protection of civil targets. Conclusions and Relevance. We provide the rationale for field tests of electrical facilities of infrastructure systems, including energized ones and having different load. As a result of such field test, it will be possible to determine whether the existing (and future) protective facilities and systems are efficiently used to ensure the resilience of electrotechnical equipment to the electromagnetic impulse of a high-altitude nuclear explosion, deliberate destructive effects of powerful electromagnetic generators, lightning overvoltage.

The content of 53 micro- and ultramicroelements in otoliths of two deep-sea fish species, blue antimora Antimora rostrata from the Northwest Atlantic (NWA) and Pacific flatnose Antimora microlepis from the Northeast Pacific (NEP), is studied. The otoliths of these species were characterized by the maximum concentration of strontium, nickel, zinc, barium, chromium, copper, lithium, cobalt, and zirconium (in descending order). The content of barium, tungsten, and lithium was higher in otoliths of the former species, while that of yttrium and uranium, in otoliths of the latter. This is probably due to differences in the chemical composition of NWA and NEP waters, as well as to differences in the linear size of fishes and changes in the concentrations of individual elements during ontogeny. The lead, arsenic, zinc, copper, and nickel contents in the otoliths, kidneys, muscles, and liver of fishes from different areas are compared.

We have studied the effect of precursors on the synthesis conditions and characteristics of molybdenum nitrides. Mo, MoO3, and MgMoO4 powders were nitrided in flowing ammonia at temperatures in the range 500–800°C. The use of molybdenum nanopowder as a precursor has made it possible to reduce the synthesis temperature and time. We have demonstrated the possibility of direct ammonolysis of the double oxide MgMoO4. Using this molybdate, we have obtained a material with a specific surface area up to 29 m2/g, which is a factor of 2 to 3 larger than that reached by nitriding MoO3. In all cases, the synthesis products consisted of the γ- and β-phases of Mo2N, with cubic and tetragonal lattices, respectively.

The contribution of magnetoelastic effects to the effective magnetic anisotropy of a three-layer film nanodisk (nonmagnetic metal/ferromagnet/nonmagnetic metal) was studied. The mechanical stresses at the lateral surface of the disk that are caused by two factors, i.e., unequal thermal expansion of layers and excess surface energy at the layers interfaces, were estimated. The case in which the contribution of magnetoelastic effects to the anisotropy is comparable with those of shape and crystalline anisotropies was discussed. It was shown that the main reason for the change in the local anisotropy field in the vicinity of a nanodisk edge was the mechanical stresses induced by the excess surface energy. The possible application of film nanodisks of nickel with a bilateral golden coating as “nanolancets” for noninvasive cell surgery of tumors was discussed.

We propose a method for calculating the electronic band structure of disordered systems with strong electron correlations. Various approaches to the description of electrical conductivity of disordered systems are considered. Calculations are based on determining the one-particle Green function of the system, which is averaged over different configurations of a cluster, on the Boltzmann formalism, and the Kubo linear response theory. As the basic model, we use the Hubbard model for an A1 – xBx binary alloy.

Anisotropic periodic relief in form of ripples was formed on surface of amorphous hydrogenated silicon (a-Si:H) films by femtosecond laser pulses with the wavelength of 1.25 μm. The orientation of the surface structures relative to laser radiation polarization vector depended on the number of laser pulses N acting on the film surface. When N = 30, the structures with 0.88 μm period were formed orthogonal to the laser radiation polarization; at N = 750 the surface structures had period of 1.12 μm and direction parallel to the polarization. The conductivity of the laser-modified a-Si:H films increased by 3 to 4 orders of magnitude, up to 3.8·10–5 (Ω∙cm)–1, due to formation of nanocrystalline Si phase with a volume fraction from 17 to 30%. Anisotropy of the dark conductivity, as well as anisotropy of the photoconductivity spectral dependences was observed in the modified films due to depolarizing influence of periodic microscale relief and uneven distribution of nanocrystalline Si phase within such laser-induced structure.

The results on the studies on age and growth in Pacific flatnose (fine-scale antimora) Antimora microlepis from the waters of underwater Emperor mounting range (open water of northwestern part of Pacific Ocean) are presented. In the long-line catches the fish with body lengths of 43.5−84.0 cm and body weights of 550−5640 g at the age of 18−46 years ae noted. The specimens at the age of 24−33 years prevail (68.8%). The age of females varies within 18−46 years (30 years on average); of males, 19−36 years (27 years on average). Comparing to the specimens from the waters off Kuril islands and Kamchatka of the Pacific Ocean, the fish from the Emperor mounting range exhibit slower growth rate.

A new genus Proeumicrotremus gen. nov. is established for the Soldatov’s lumpsucker Eumicrotremus soldatovi. The new genus differs from Eumicrotremus in a number of plesiomorphies in the structure and location of the external body armour, as well as in body proportions and a greater maximum length. Proeumicrotremus occupies an intermediate position between generalized genera and Eumicrotremus in the Cyclopteridae family system.

В данной работе изложен анализ уровня описания главных физических процессов в атмосфере Земли в современных моделях общей циркуляции атмосферы Земли и дан краткий обзор современных моделей, используемых основными прогностическими центрами. Обсуждаются перспективные направления развития моделей общей циркуляции атмосферы Земли.

In this study, we analyze the evolution of current-voltage characteristics of a quasi-one-dimensional TaS3 conductor under uniaxial tension in the temperature range of 150–40 K. At all temperatures, elongation is found to lead to formation of an “ultracoherent” charge density wave (CDW) the main feature of which is a sharp increase in conductivity under an electric field that is higher than the threshold: above 100 K, the transition in the dependence on e occurs almost abruptly while, below 90 K, elongation leads to an intermediate region in which the threshold field increases sharply and is poorly defined due to weak nonlinear conductivity. The result proves the occurrence of a spatially non-uniform state of the CDW below 90 K.

The composition, principle of operation and basic metrological characteristics of the State Primary Special Standard of acceleration for gravimetry GET 190-2019 are given. The standard is the top link of the reference base for gravitational acceleration measurements. The accuracy and reliability of GET 190-2019 have been increased as a result of optimization of methods for adjusting measuring systems and the inclusion of improved systems, assemblies and modern element base in its composition. Particular attention is paid to the refinement of the corrections introduced into the measurement results due to methodological, physical and technical limitations. The applied research methods made it possible to confirm the range of GET 190-2019, as well as to determine the contributions of the main sources and the total value of the error. The metrological characteristics of GET 190-2019 are confirmed by the results of measurements of the absolute value of gravimetric acceleration at the gravimetric station Lomonosov-1 and their comparison with the data obtained at different times using high-precision foreign and domestic gravimeters. The relevance of the work is determined by the requirements of applied problems whose solution requires data on the parameters of the Earth’s gravitational field. Geophysics and navigation are the main areas of application for high precision measurements in this field.