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We discuss determinant formulas for the partition function of the six-vertex model with domain wall boundary conditions, which are parametrized by an arbitrary basis of polynomials. In this note we show that our recent result on this problem admits a one-parameter extension. [ABSTRACT FROM AUTHOR]

The mine shafts in the salt (unwatered) rock mass at the Upper Kama deposit are mostly lined with cast-in-place concrete and reinforced concrete, which should ensure the required load-bearing capacity and water impermeability in host rocks in creep. The long-term observations of the shaft lining in operation revealed some typical patterns of failure induced by the rheological properties of salt rock mass under the action of rock pressure. The technical evaluation of the lining and reinforcement of mine shafts is an integrated checkup procedure including measurements of fractures and areas of corrosive zones/rock falls; updating of actual geometrics of lining from laser measurements; determination of residual strength of lining; mathematical modeling; estimation of integral reliability index of lining. The authors propose a procedure to categorize technical conditions of concrete lining in mine shafts in operation in salt-bearing rock mass in creep. The application of the procedure is described, and the conclusions on the package of repair activities are drawn. [ABSTRACT FROM AUTHOR]

Data on the biology and ecology of the Eurasian dotterel Eudromias morinellus from the largest mountain range of the Russian Arctic are presented. The data were obtained in the years 1988–2018. It has been established that, during the breeding season, the species covers a wide range of altitudes, settles on flat tops almost everywhere within the alpine belt, locally occurs in some parts of the subalpine belt, and is extremely rarely recorded in the mountain–taiga belt. Its range has a clearly defined three-dimensional character. Its optimal habitats in the alpine belt are confined to dry stony areas of the mountain tundra, which have a hummocky microrelief and are covered with sparse herbaceous vegetation. The abundance of the species during the breeding season varies from 0.4 to 10.0 (mean 1.7) individuals/km2 in optimal habitats within the alpine belt, gradually decreasing to both the tops (1.3 ind./km2) and foothills of slopes (3.5 ind./km2). Thus, 70% of all Eurasian dotterel individuals are concentrated in the central part of the alpine belt (which covers 42% of the vertical living space of this species) during the breeding period. Until the middle of the third ten-day of June, females actively lek in flight and on the ground both singly and in groups of up to 15 individuals. Egg laying begins on June 7–22, when the snow cover is often almost complete. Nests are at altitudes of 850–1036 (mean 935 ± 28) m a.s.l. (n = 8). The local nesting density, determined from the average minimum distance between neighboring nests, can be 1.67 nests/km2. The earliest estimated date of the appearance of chicks is July 3 and the latest date is July 18 (the average date is July 9 ± 1 day) (n = 13). Chicks of the same brood hatch within one day. [ABSTRACT FROM AUTHOR]

The change in the octupole deformation of nuclei in the chain of even–even radium isotopes is studied on the basis of the Hartree–Fock–Bogoliubov method with an effective Skyrme interaction. Nucleon pairing is described in terms of density-dependent zero-range pairing forces of mixed type. Conditions imposed on the quadrupole and octupole moments of nuclei were used in respective calculations. The dependence of the calculated features of nuclei on the choice of pairing forces is studied. The calculations show that there is a strong dependence of the octupole deformation of nuclei on the choice of parameters of nucleon-pairing forces. [ABSTRACT FROM AUTHOR]

We consider actions of the current Lie algebras gl n [ t ] and gl k [ t ] on the space of polynomials in kn anticommuting variables. The actions depend on parameters z ¯ = (z 1 , ⋯ , z k) and α ¯ = (α 1 , ⋯ , α n) , respectively. We show that the images of the Bethe algebras B α ¯ ⟨ n ⟩ ⊂ U (gl n [ t ]) and B z ¯ ⟨ k ⟩ ⊂ U (gl k [ t ]) under these actions coincide. To prove the statement, we use the Bethe ansatz description of eigenvalues of the actions of the Bethe algebras via spaces of quasi-exponentials and establish an explicit correspondence between these spaces for the actions of B α ¯ ⟨ n ⟩ and B z ¯ ⟨ k ⟩ . [ABSTRACT FROM AUTHOR]

Non-commutative space-time is discussed for discrete case. An exact discretization of the non-commutative space-time is proposed. New discrete operators, which satisfy the same algebraic relations as standard derivatives of integer orders, are used. Exact discretization of the non-commutative space-time is suggested by using generalization of the star-product (the Moyal–Weyl product) based on the recently proposed exact finite differences. The suggested discrete non-commutative space-time corresponds to the standard "continuous" non-commutative space-time without any approximations. The suggested discrete non-commutative space-time can be interpreted as a special physical (crystal) lattice with long-range interaction. [ABSTRACT FROM AUTHOR]

Several tundra wader species occasionally nesting in the former Orenburg Province in the second half of the 19th century were reported by the prominent researchers of the avifauna of that region E.A. Eversmann, N.A. Zarudnyi, and P.P. Sushkin among others. In most cases, the scientists based their assumptions on circumstantial evidence alone, for instance, summer records of adult birds and migrating broods. Taking into account the specific biology of the species in question, such data could not be regarded as sufficient proof for the species' nesting. In the middle of the 20th century, these data were revised and quite justly criticized: this led to varying conclusions regarding the nesting of tundra wader species in the region as having been wrong. The matter seemed to be settled. Yet it should be noted that, along with circumstantial data on the nesting of northern waders, the early researchers had also reported very solid facts like finding nests with clutches of eggs and nonflying chicks (including the Red-necked Phalarope and the Little Stint). For certain reasons, those facts were not considered during the revision that followed. Firstly, it was difficult to find an explanation for such outstanding evidence in the middle of the 20th century. Secondly, no new nests of those species were found that could confirm the 19th century researchers as having been right. Furthermore, the idea that long-term cycles of climate changes influence the dynamics of bird nesting areas became widely accepted only by the end of the 20th century. Nowadays when this idea has been thoroughly developed, the possibility of the former nesting of some tundra wader species in arid regions does not seem so incredible. It seems likely that Zarudnyi and Sushkin were the last scientists to witness the nesting of tundra wader populations in the Orenburg region as over time due to climate warming the waders might have left the region for good. [ABSTRACT FROM AUTHOR]

This paper presents the results of a total census of inhabited Dalmatian Pelican nests, which was carried out in spring 2017 using a drone aircraft for the waterbodies of the Kurgan and Tyumen regions. The dynamics of the species numbers in the area studied over the last 50–70 years and the factors affecting these dynamics are analyzed. [ABSTRACT FROM AUTHOR]

Ground-state properties of even-even nuclei were calculated over a broad region of mass numbers, including nuclei that contain a neutron excess in the vicinity of the neutron drip line. The calculation of the properties of such nuclei relied on the method of the relativistic and the nonrelativistic mean field and took into account the axial deformation of nuclei. Particular attention was given to nuclei beyond the theoretical neutron drip line, which form a peninsula of nuclei in the (N, Z) space at N = 184 that are stable against the emission of one or two neutrons. [ABSTRACT FROM AUTHOR]

A spectrum of differentially expressed microRNAs was determined by the massively parallel sequencing method in normal healthy prostate tissues, in hormone-dependent prostate cancer samples, and in the LNCaP and DU145 cell lines. A set of microRNAs in tumors and prostate cancer (PCa) cell lines was identified on the basis of the changes in expression compared with that in normal prostate tissues. Twenty-seven aberrantly expressed microRNAs were detected in tumor tissues and ten of them showed significant changes in expression in LNCaP and DU145 cells. Seven of them demonstrated the change of the expression in the same direction in all the tumor samples as well as in the PCa cell lines. The expression of miR-148a changed in DU145 cells in the opposite direction compared with that in LNCaP cells and tumors. The expression of let-7c, let-7b, miR-99a, miR-125b-2, miR-100, miR-10a, and miR-31 was reversed in DU145 cells compared with LNCaP cells. However, these microRNAs exhibited no significant changes in expression in tumors. It turns out that the target of miR-148a, let-7b, and microRNAs, included in the miR-99a/let-7c/miR-125b-2 cluster, the expression of which increased in LNCaP cells and decreased in DU145 cells, is the insulin-like growth factor receptor gene 1 (IGF1R). The obtained data make it possible to assume that the differences in the effect of microRNAs in cell lines are connected with their repressive influence on IGF1R expression in hormone-sensitive LNCaP cells and an absence of such influence in the hormone-independent DU145 cell line. [ABSTRACT FROM AUTHOR]

A refined physicomathematical model based on interacting mutually penetrating continua is proposed for a pneumatic conveyor to transport granular materials under the transitional and the unsteady state. In this model, the pneumatic conveyor is considered a system of mutually influencing equipment interrelated via the laws of mechanics. The proposed model of a pumping pneumatic conveyor may estimate the change of system operation parameters with time, along the transportation duct length, to select the best pneumatic conveying equipment. The suitability of this model is confirmed via experimental studies. [ABSTRACT FROM AUTHOR]

Changes in the shape of nuclei in the chains of even—even crypton, strontium, zirconium, molybdenum, and ruthenium isotopes are studied on the basis of the relativistic Hartree—Bogolyubov method implemented with the DD-PC1 and DD-ME2 Lagrangian models. Nucleon pairing is described in terms of separable two-body interaction. The dependence of the calculated nuclear features on the choice of pairing strength is investigated. The respective calculations show that, in the vicinity of N = 60, large jumps of the mean squares of charge radii and quadrupole-deformation parameters are observed for some strontium, zirconium, and molybdenum isotopes in response to variations in the pairing-strength parameters. [ABSTRACT FROM AUTHOR]

The BONUS model of the formation, radioactive interactions, and transport of fission products in nuclear fuel is modified to describe the behavior of hydrogen and helium in irradiated nuclear fuel as well as to accumulate an expanded list of transuranium actinides. The program module developed on the basis of the model is included in the MFPR/R fuel code and the SFPR and the BERKUT-U fuel rod codes. The test calculations for mixed uranium-plutonium oxide fuel and mixed uranium-plutonium nitride fuel irradiated in fast reactors are in good agreement with high-precision neutronics calculations. [ABSTRACT FROM AUTHOR]

We consider the problem of determining the characteristics of queuing systems with delay by the classical spectral decomposition method for the solution of the Lindley integral equation. As input distributions for the systems we choose mixtures of exponential distributions shifted to the right of the zero point, for which the spectral decomposition approach allows one to obtain a solution in closed form. We show that in such systems with delay, the average waiting time is shorter than in conventional systems. [ABSTRACT FROM AUTHOR]

The object of research is the hinge unit of the universal spindle of rolling mills. The most common for such conditions are used hinges with anti-friction liners with sliding friction. One of the most problematic parts of the hinge with sliding friction is the uneven distribution of pressure on the contact surface of the segments, which reduces the wear resistance of liners and operational reliability of the spindle. To identify the causes of uneven pressure and determine areas of significant excess of torsion loads, studies are carried out on the developed mathematical model of the hinge. In the course of the research, a mathematical analysis of the influence of the parameters of liners on the magnitude of pressure on the contact surfaces under the working loads of the roller blades and segments of the hinge liners is used. The parameters of the zones of high pressure in the contact liners typical forms in the form of a continuous segment with flat and cylindrical surfaces. It is established that it is necessary to change the liner section plane along the length and width of the segment. Analytical dependences of the hinge parameters on the active loads and pressure are obtained. The formulas for determining the geometric dimensions of the hinge segments with regard to its radius and rigidity are derived. The study of the hinge with inserts, in which bevels on a flat surface and slopes to the ends along the length and from the middle to the side faces, indicates the possibility of uniform distribution of pressure along the length and width of the segments of the inserts. Thus, research on the mathematical model and in the laboratory has shown that it is advisable to use the developed design of the liner with a variable section plane along the length and width of the liner. The uniform distribution of contact loads is confirmed by pressure plots along the length and width of the segments. This makes it possible to increase the wear resistance of the hinge joint of universal spindles of powerful rolling mills. Compared with the known designs of hinges, the operational reliability of the spindles and the period of trouble-free operation of states are significantly increased. [ABSTRACT FROM AUTHOR]

For the periodic isotropic Heisenberg model with arbitrary spins and inhomogeneities, we describe the system of algebraic equations whose solutions are in bijection with eigenvalues of the transfer-matrix. The system describes pairs of polynomials with the given discrete Wronskian (Casorati determinant) and additional divisibility conditions on discrete Wronskians with multiple steps. If the polynomial of the smaller degree in the pair is coprime with the Wronskian, this system turns into the standard Bethe ansatz equations. Moreover, if the transfer-matrix is diagonalizable, then its spectrum is necessarily simple modulo natural degeneration. [ABSTRACT FROM AUTHOR]

When describing the dynamics of quantum systems interacting with a coherent external electromagnetic field, the instant at which the exciting (measuring) field begins to act is traditionally taken as zero time in the laboratory frame. Using the concept of coherence sudden death in an observed quantum system, we introduce the definition of local, completely incoherent subensembles of the quantum system in which it is found with a certain probability at each instant of time in the process of a continuous observation (measurement). For such subensembles an arbitrary instant of time in the laboratory frame is the initial time of the interaction with the external (measuring) field. As a result, the dynamics of an open quantum system is represented by a superposition of the dynamics of local subsystems with a continuous distribution of the times at which the interaction with the external field begins. We have derived an expression for the dynamical “multitime” contribution to the stationary solution of the Bloch equations, which clearly demonstrates the meaning of time relativity in the dynamics of two-level quantum systems in the semiclassical approximation. This dynamical multitime contribution is shown to explain the emergence of quantum beats at zero frequency (the Hanle effect, the level crossing) in EPR. [ABSTRACT FROM AUTHOR]

The frequency-field and orientation dependences of the electron paramagnetic resonance (EPR) spectra are measured for impurity Tm3+ ions in yttrium orthosilicate (Y2SiO5) single crystals by stationary EPR spectroscopy in the frequency range of 50-100 GHz at 4.2 K. The position of the impurity ion in the crystal lattice and its magnetic characteristics are determined. The temperature dependences of the spin-lattice and phase relaxation times are measured by pulse EPR methods in the temperature range of 5-15 K and the high efficiency of the direct single-phonon mechanism of spin-lattice relaxation is established. This greatly shortens the spin-lattice relaxation time at low temperatures and makes impurity Tm3+ ions in Y2SiO5 a promising basis for the implementation of high-speed quantum memory based on rare-earth ions in dielectric crystals. [ABSTRACT FROM AUTHOR]

The theory of bipolar charging of aerosol particles is developed for large particles (≥10 µm), taking into consideration the Coulomb field screening effect, which becomes relatively strong under conditions of high ion concentration attained in ionizers, . The corresponding generalized kinetic model is based on the diffusion equations for positively and negatively charged ions migrating to the central particle in the collective electrostatic field with the potential obeying the Poisson equation (rather than the Laplace equation, as in the traditional approach). Direct numerical calculations show that the Coulomb field screening becomes especially important for very large particles, which can be eventually charged to the values, several times exceeding those calculated in the traditional approach. Copyright © 2018 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

The article describes the thermolysis process of sodium borohydride dihydrate in thermoanalytical experiments. The reaction was carried out without solid catalyst and with catalyst as cobalt boride Co2B. It has been found out that in both cases the process starts after the peritectic reaction of the starting compound and forms a liquid phase. The enthalpy of peritectic reaction is ΔHreact = 19 ± 2 kJ mol−1. When thermolysis proceeds in acetonitrile solution without a catalyst, intermediate hydroxyborohydride NaBH3OH or/and Na(BH3)2OH is formed according to the NMR experiment data. The formation of similar complexes in the solid phase is confirmed by experiments on the oxidation of the thermolysis products. Thermolysis process with solid catalyst proceeds with an intense exothermic effect at more lower temperatures. The kinetics of the non-catalytic process is described by the model of two consecutive reactions, and reaction with the solid catalyst model is approximated by two parallel reactions. [ABSTRACT FROM AUTHOR]

The article describes the thermolysis process of sodium borohydride dihydrate in thermoanalytical experiments. The reaction was carried out without solid catalyst and with catalyst as cobalt boride Co2B. It has been found out that in both cases the process starts after the peritectic reaction of the starting compound and forms a liquid phase. The enthalpy of peritectic reaction is ΔHreact = 19 ± 2 kJ mol−1. When thermolysis proceeds in acetonitrile solution without a catalyst intermediate hydroxyborohydride NaBH3OH and/or Na(BH3)2OH is formed according to the NMR experiment data. The formation of similar complexes in the solid phase is confirmed by experiments on the oxidation of the thermolysis products. Thermolysis process with solid catalyst proceeds with an intense exothermic effect at lower temperatures. The kinetics of the non-catalytic process is described by the model of two consecutive reactions, and reaction with the solid catalyst model is approximated by two parallel reactions. [ABSTRACT FROM AUTHOR]

Using multiple parallel sequencing on Illumina platform, we identified eight microRNAs that showed significant opposite changes of gene expression in cells of the hormone-sensitive LNCaP prostate cancer cell line and in cells of the hormone-resistant DU-145 cell line, in comparison to the microRNA expression in the normal prostate tissue cells. We found that the insulin-like growth factor 1 receptor (IGF1R) gene is a target of five microRNAs whose expression is increased in LNCaP cells and reduced in DU-145 cells. [ABSTRACT FROM AUTHOR]

We studied the phenotypic composition of the populations and variability of songs in two bunting species in three localities on the western border of the sympatry zone: in the southern part of Tyumen’ oblast and in the center and southern of Kurgan oblast. Over the last several decades, the zone of contact of the studied species has expanded significantly. The pine bunting started breeding regularly in the area at the end of the 20th century, and at present it is considered a common species comparable in abundance to the yellowhammer. The share of phenotypic hybrids varies from 25 to 50% reaching its maximum at the boundary of the pine bunting’s nesting range. East of this boundary, the hybridization level is reduced, this being seen in a sharp decrease in the share of “leucocephala hybrids.” An analysis of the phenotypic variability of the hybrids shows that they can be divided into two groups similar in coloration to the parental species. The study results let us presume that the hybridization is limited and hybrids return mostly to backcrossing with the parental species. This presumption also finds support in an analysis of the song structure: the yellowhammer and the pine bunting have songs of different, easily distinguishable dialects. [ABSTRACT FROM AUTHOR]

In this paper we present the analytical expression for the neutron scattering law for an isotropic source of neutrons, obtained within the framework of the gas model with the temperature of the moderating medium as a parameter. The obtained scattering law is based on the solution of the general kinematic problem of elastic scattering of neutrons on nuclei in the L-system. Both the neutron and the nucleus possess arbitrary velocities in the L-system. For the new scattering law we obtain the flux densities and neutron moderation spectra as functions of temperature for the reactor fissile medium. The expressions for the moderating neutrons spectra allow reinterpreting the physical nature of the underlying processes in the thermal region. [ABSTRACT FROM AUTHOR]

Paramagnetic centers formed by impurity Yb ions in synthetic forsterite (MgSiO) grown by the Czochralski technique are studied by X-band CW and pulsed EPR spectroscopy. These centers are single ions substituting magnesium in two different crystallographic positions denoted М1 and М2, and dimer associates formed by two Yb ions in nearby positions М1. It is established that there is a pronounced mechanism favoring self-organization of ytterbium ions in dimer associates during the crystal growth, and the mechanism of the spin-spin coupling between ytterbium ions in the associate has predominantly a dipole-dipole character, which makes it possible to control the energy of the spin-spin interaction by changing the orientation of the external magnetic field. The structural computer simulation of cluster ytterbium centers in forsterite crystals is carried out by the method of interatomic potentials using the GULP 4.0.1 code (General Utility Lattice Program). It is established that the formation of dimer associates in the form of a chain parallel to the crystallographic axis consisting of two ytterbium ions with a magnesium vacancy between them is the most energetically favorable for ytterbium ions substituting magnesium in the position М1. [ABSTRACT FROM AUTHOR]

We studied microRNA gene expression in HeLa cells following exposure for 6 h and 8 days to Co gamma rays at a dose of 4 Gy using an approach of large-scale parallel DNA sequencing. We identified 12 microRNAs with aberrant expression which were maintained in cell generations. The analysis of radiation-induced aberrant expression of pre-microRNAs made it possible to assess the importance of nuclear and cytoplasmic stages of microRNA biogenesis for preservation of its aberrant expression. On cell treatment by 5-azacytidine, aberrant expression was maintained only in two microRNAs: miR-21-3p and miR-422a, which demonstrated an increase in expression. Radiation-induced decrease in expression in ten examined microRNAs was dependent on DNA demethylation. At the same time, expression in a microRNA set, which demonstrated inheritable alteration of the expression after gamma-radiation exposure in the untreated cells, was not dependent or was weakly dependent on DNA methylation. The obtained results suggest that ionizing radiation induces aberrant DNA methylation, which affects inherited expression changes in microRNAs in cell generations after exposure to the mutagen. [ABSTRACT FROM AUTHOR]

Currently, the most actively developing area in the field of permanent magnets is development of those based on compounds of rare-earth metals with transition metals. This is due to their unique magnetic properties that surpass those for ferrite and lithium magnets by several factors and makes them irreplaceable with utilization in aero and automobile building, robot technology, computers, etc. Among all of the compounds of iron with rare-earth elements, the greatest iron content and, consequently, highest saturation magnetization applies to RFe compounds (R is rare-earth element). Regimes are studied for nitriding alloy powders (SmZr)Fe and Sm(FeCo) in a nitrogen atmosphere with excess pressure of 15 kPa and temperature of 440-450°C. Dependences are established for phase composition and main magnetic parameters of nitriding regime. [ABSTRACT FROM AUTHOR]

In this paper, the hazard of adverse heat effect on permafrost soil as a result of viscous oil production in the Far North is studied with the method of thermocompression supply of superheated water steam to the oil-bearing layer. It is found that, due to the divergent nature of heat transfer and convective complex movement of air in the space between the tubing and the casing, the temperature of the latter in the area of load-bearing elements heated to 130°C is about 70°C. The heterogeneity of the temperature field is leveled up to 4-5% at a distance of 400-420 mm from the axis of the tubing. The thickness of the melting layer of ground ice within 90 days of operation of the tubing depends on the percentage of water-filled pores in the soil. With the minimum (10%) percentage of water-filled pores in the soil layer, the thickness of the ground ice melting layer for 90 days of operation of the tubing does not exceed 2.6 m. [ABSTRACT FROM AUTHOR]

The dependence of expression of miRNAs and their precursors (pre-miRNAs) on the DNA methylation level in HeLa cells 8 days after mitomycin C treatment was studied. A massive parallel DNA sequencing method was applied to analyze miRNA expression. 5-Azacytidine (DNA methylation inhibitor) was added to the medium 6 days after mutagenic agent exposure. The results indicated that the change in expression for some mature miRNAs (39 of 61) was accompanied by the change in the expression of their pre-miRNAs, while there were no significant changes in the expression of pre-miRNA for other mature miRNAs (22 of 61). The aberrant expression was maintained by 8 of 61 mature miRNAs and 6 of 55 pre-miRNAs in the induced HeLa cells after 5-azacytidine treatment. In addition, the expression of more than 90% of miRNAs, which indicated a significant change in expression after mitomycin C treatment, does not depend or depends slightly on the DNA methylation level in HeLa cells without mitomycin C treatment. The results suggest that mitomycin C induces aberrant DNA methylation which affects maintenance of changes in the miRNA expression in cell generations after mutagen treatment. [ABSTRACT FROM AUTHOR]

A signal related to the spin level crossing in a zero magnetic field-the Hanle effect-has been registered for the first time in the EPR spectrum. It has been shown that, in the general case, the shape of the signal is determined by two qualitatively different mechanisms: (i) the interference of unsteady-state contributions to the dynamics of atomic coherences (electric or magnetic quantum transition moments with certain phases) with close frequencies ('beats at a zero frequency') and (ii) the summation of resonant signals determined by the steady-state dynamics of the same atomic coherences. The relaxation time of spin coherences has been determined for the EPR transition of Tm ions in synthetic forsterite. [ABSTRACT FROM AUTHOR]

The specific features of the EPR spectra of Tm impurity ions in synthetic forsterite have been studied by continuous-wave EPR spectroscopy in the frequency range of 270-310 GHz at a temperature of 4.2 K in weak magnetic fields. Narrow resonance signals unrelated to the modulation of the resonance conditions of EPR under the modulation of the external magnetic field have been discovered in measurements at frequencies corresponding to the zero field splitting between the ground and first excited singlet electron states of Tm ions in zero magnetic field. The origin of these narrow lines is discussed. [ABSTRACT FROM AUTHOR]

We discuss the procedure of extracting the photoproduction cross section for neutral pseudoscalar mesons off neutrons from deuteron data. The main statement is that the final-state-interaction corrections for the proton and neutron target are in general not equal, but for π production there are special cases where they have to be identical and there are large regions in the parameter space of incident photon energy and pion polar angle, Θ*, where they happen to be quite similar. The corrections for both target nucleons are practically identical for π0 production in the energy range of the Δ(1232)3/2+ resonance due to the specific isospin structure of this excitation. Also above the Δ-isobar range large differences between proton and neutron correction factors are only predicted for extreme forward angles (Θ* *lt; 20°), but the results are similar for larger angles. The case of η photoproduction is also briefly considered. Numerical results for the γp → π p and γ n → π n correction factors are discussed. Also the model description for the available data on the differential γ d → π pn cross sections are given. [ABSTRACT FROM AUTHOR]

We study H/H/1, H/M/1, and M/H/1 queueing systems with hyperexponential arrival distributions for the purpose of finding a solution for the mean waiting time in the queue. To this end we use the spectral decomposition method for solving the Lindley integral equation. For practical application of the obtained results, we use the method of moments. Since the hyperexponential distribution law has three unknown parameters, it allows to approximate arbitrary distributions with respect to the first three moments. The choice of this distribution law is due to its simplicity and the fact that in the class of distributions with coefficients of variation greater than 1, such as log-normal, Weibull, etc., only the hyperexponential distribution makes it possible to obtain an analytical solution. [ABSTRACT FROM AUTHOR]

Consideration was given to the problem of determining the characteristics of queuing system with delay with the use of the spectral decomposition of the solution of the Lindley's integral equation. The load of such system was shown to exceed that of the classical M/M/1 system, and the mean waiting time is smaller. [ABSTRACT FROM AUTHOR]

We consider the cotangent bundle T ∗ F λ of a G L n partial flag variety, λ = ( λ 1 , … , λ N ) , | λ | = ∑ i λ i = n , and the torus T = ( C × ) n + 1 equivariant K -theory algebra K T ( T ∗ F λ ) . We introduce K -theoretic stable envelope maps Stab σ : ⨁ | λ | = n K T ( ( T ∗ F λ ) T ) → ⨁ | λ | = n K T ( T ∗ F λ ) , where σ ∈ S n . Using these maps we define a quantum loop algebra action on ⨁ | λ | = n K T ( T ∗ F λ ) . We describe the associated Bethe algebra B q ( K T ( T ∗ F λ ) ) by generators and relations in terms of a discrete Wronski map. We prove that the limiting Bethe algebra B ∞ ( K T ( T ∗ F λ ) ) , called the Gelfand–Zetlin algebra, coincides with the algebra of multiplication operators of the algebra K T ( T ∗ F λ ) . We conjecture that the Bethe algebra B q ( K T ( T ∗ F λ ) ) coincides with the algebra of quantum multiplication on K T ( T ∗ F λ ) introduced by Givental (2000), Givental and Lee (2003). The stable envelope maps are defined with the help of Newton polygons of Laurent polynomials representing elements of K T ( T ∗ F λ ) and with the help of the trigonometric weight functions introduced in Varchenko and Tarasov (1994), Tarasov and Varchenko (2013) to construct q -hypergeometric solutions of trigonometric qKZ equations. The paper has five appendices. In particular, in Appendix E we describe the Bethe algebra of the XXZ model by generators and relations. [ABSTRACT FROM AUTHOR]

Using HF + BCS method we study light nuclei with nuclear charge in the range 2 ≤ Z ≤ 8 and lying near the neutron drip line. The HF method uses effective Skyrme forces and allows for axial deformations. We find that the neutron drip line forms stability peninsulas at 18He and 40C. These isotopes are found to be stable against one neutron emission and possess the highest known neutron to proton ratio in stable nuclei. [ABSTRACT FROM AUTHOR]

On the basis of the condition for nuclear burning wave existence in the neutron-multiplying media (U-Pu and Th-U cycles) we show the possibility of surmounting the so-called dpa-parameter problem and suggest an algorithm of the optimal nuclear burning wave mode adjustment, which is supposed to yield the wave parameters (fluence/neutron flux, width and speed of nuclear burning wave) that satisfy the dpa-condition associated with the tolerable level of the reactor materials radioactive stability, in particular that of the cladding materials. It is shown for the first time that the capture and fission cross sections of 238U and 239Pu increase with temperature within 1000–3000 K range, which under certain conditions may lead to a global loss of the nuclear burning wave stability. Some variants of the possible stability loss due to the so-called blow-up modes (anomalous nuclear fuel temperature and neutron flow evolution) are discussed and are found to possibly become a reason for a trivial violation of the traveling wave reactor internal safety. [ABSTRACT FROM AUTHOR]

We study the stability of elastic systems with one-sided constraints on displacements. We analytically solve the contact problem for rods and propose a new method for solving contact problems with a free boundary. We present numerical results concerning the stability of elastic systems with one-sided constraints on displacements. Bibliography: 10 titles. [ABSTRACT FROM AUTHOR]

Corrosion resistance of hard magnetic SmFeN materials is studied. It is shown that addition of cobalt (up to 8 wt.%) makes it possible to improve corrosion resistance of these materials by 20-25% without reducing their magnetic properties. It is established that additional treatment of SmFeN powder with organosilicon liquid GKZh 136-41 makes it possible to improve corrosion resistance by a factor of 2-3. [ABSTRACT FROM AUTHOR]

Applying the method of multiple parallel sequencing on the MiSeq platform (Illumina, United States), a comparative analysis of miRNA expression in tumor and normal colon tissue cells was performed. Forty miRNAs aberrantly expressed in cancer were detected. Among them, 15 and 25 miRNAs showed increased and decreased expression, respectively, for all or most of the cases. Sixteen miRNA clusters were identified, which showed a coordinated or incompletely coordinated aberrant expression in colorectal cancer cells. In two (miR-183/182 and miR-106b/25) and four (miR-143/145, miR-497/195, miR-30e/30c-1, and miR-30a/30c-2) miRNA clusters, respectively, a statistically significant coordinated increase or decrease in expression was registered for all miRNAs within the corresponding cluster. Three aberrantly expressed well-known miRNAs (miR-100-5p, miR-30d-5p, and miR-204-5p) were identified, which, however, had never before been associated with colorectal cancer. The obtained results demonstrate the potential and promising application of 6 miRNA clusters with coordinated aberrant expression as markers for colorectal cancer. [ABSTRACT FROM AUTHOR]

The statistical parameters of hydrodynamic heteroadagulation of microdrops of solar oil with sizes of 0.5-2 μm have been obtained for the first time. The problem is of a great practical significance because the agglomeration of microdrops leads to substantial acceleration of purification of aqueous phase from them according to hydrodynamic heteroadagulation (HHA). HHA has been studied in the broad range of the rotation frequencies of rotor discs from 200 to 2000 min. Root-mean-square deviations S have been calculated in all points of kinetic curves and also their relative errors δ% have been obtained. The methods of analyzing the u-distributions and Student t-distributions have been used. The trends of random deviations of kinetic curves of heteroadagulation from mean values have been determined. [ABSTRACT FROM AUTHOR]

We identified 40 miRNAs with inherited aberrant expression by multiple parallel sequencing of human HeLa cells irradiated with X rays and mitomycin C. Twenty-two miRNAs were repressed and 15 miRNAs were induced after radiation and mytomycin C treatment. The expression of three miRNAs (miR-10b-5p, miR-148a-3p, and miR-340-5p) decreased after X-ray exposure and increased after mitomycin C treatment. The spectrum of aberrantly expressed miRNAs after X-ray and mitomycin C treatment is different, except for three miRNAs (mir-100-5p, miR-99b-5p, miR-501-3p), which showed the inherited decreased expression after both mutagens. It has been ascertained that for five miRNAs (miR-21-3p, miR-182-5p, miR-19b-3p, miR-30a-3p, and miR-30e-3p) with increased inherited expression, the targets are well-described tumor suppressor genes. For 9 miRNAs (miR-99b-5p, miR-148a-3p, miR-365a-3p, miR-193a-3p, miR-100-5p, miR-99a-5p, miR-29b-3p, miR-340-5p, and miR-23b-3p) with reduced inherited expression, the targets are oncogenes. The obtained results provide further support of the idea that induced epigenetic changes in the genome should be considered when assessing the long-term genetic effects of ionizing radiation and chemical compounds. [ABSTRACT FROM AUTHOR]