Vol 487, No 5 (2019)

We give a generalization of the so-called superposition principle for probability solutions to the Cauchy problem for the Fokker-Planck-Kolmogorov equation, according to which such a solution is generated by a solution to the corresponding martingale problem.

In this paper, we consider new sufficient conditions of optimality of the second-order for equality constrained optimization problems, which essentially enhance and complement the classical ones and are constructive. For example, they establish equivalence between sufficient conditions in the equality constrained optimization problems and sufficient conditions for optimality in equality constrained problems by reducing the latter to equalities with the help of introducing slack variables. Previously, when using the classical sufficient optimality conditions, this fact was not considered to be true, that is, the existing classical sufficient conditions were not complete, so the proposed optimality conditions complement the classical ones and close the question of the equivalence of the problems with inequalities and the problems with equalities when reducing the first to the second by introducing slack variables.

The observation of stimulated Raman scattering (SRS) in magnesium silicate Ca₂MgSi₂O₇, entering the family of D³_2d-tetragonal acentric crystals with the structure of melilite, is reported. The registered components of the Stokes and anti-Stokes Χ⁽³⁾-nonlinear crystal lasing are identified with two active SRS‑modes _ωSRS1 ≈ 908 cm^‑1 and _ωSRS2 ≈ 668 cm^‑1, which also manifest in the generation of combined phonon modes _ωSRS3C ≈ 170 cm^‑1 and _ωSRS4C ≈ 1270 cm^‑1.

Stability of vertical position of an inverted pendulum under action of support vibration as well as the attraction basin of this position is considered. In addition to the classic Kapitsa problem for the harmonic vibration of support, the poly-harmonic and random vibration of support is investigated. The condition of stability of vertical position is determined and the attraction basin of this stable position is studied.

New water-soluble nickel and cobalt complexes-sodium cobalt pectinate (PNaCo) and sodium nickel pectinate (PNaNi)-have been obtained from sodium pectinate with a salt formation extent of 35%, and their physicochemical properties have been studied. Antimicrobial activity of PNaCo and PNaNi against gram-positive and gram-negative bacteria and fungi has been shown.

The paper reports on the synthesis of nanostructured low-temperature transition alumina island coatings on the surface of macropores of permeable monolithic hierarchically porous nickel. It is established that hexagonal alumina nanoplates are the primary structural elements of the coating.

For the first time, the characteristic properties of proto-mineral (pre-crystallization) clusters-quatarons formed in supersaturated media and considered as special forms of the structural organization of matter in the nanoworld are systematically described. The possible existence of such clusters was reported in 1998, and today the phenomenon of pre-crystallization structuring of matter is recognized as a proven fact, and there is still little information about their unusual properties and behavior, there are no direct observations.

The paper presents the results of geological, geochemical and isotope-geochronological studies of subvolcanic rhyolites of the Western Gorny Altai and Rudny Altai which have related to two large volcanic systems, the Altai-Minusinsk and Altai-Salair, respectively. The results of U-Pb isotopic dating of zircons revealed two groups of ages ~410-405 and 390-381 million years. Isotope-geochemical characteristics of rhyolites show relatively high values of ε_Nd(T) = +2,7...6,0 with relatively young values of model ages T(DM) = 851-966 Ma in the Rudny Altai and more ancient - up to 1266 Ma in the West Gorny Altai. Geochemical characteristics indicate that its composition is consistent with transitional field between within-plate and island-arc felsic magmas. The results obtained correspond to the two-stage evolution of volcanism and its migration from the continent to the ocean.

The correlation of allochthonous lithotectonic complexes of the Pacific allows to establish Early Jurassic (Sinemurian-Toarcian) anoxic event (J₁-OAE) for time in the Asia-West Kamchatka region. This event is characterized by organic-riched black cherts and shales bearing pyrite that accumulated in the euxinic oceanic deep water basins of the Pacific. Later anoxic regime gradually weakened that was reflected in dominating of Midle-Upper Jurassic red gematite jaspers. J₁-OAE in the Pacific was synchronous to global warming induced by planetary magmatic activity. Volcanic gases and hydroterms stimulated euxinic conditions in the deep water basins. The Sinemurian-Toarcian interval of the OAE in the Pacific Ocean is confirmed by data of the numerous World basins.

The sorption-desorption balance of barium at the interaction of muddy-sandy terrigenous material with seawater was experimentally determined. The average value of barium desorption in the mixing zone of river and sea waters is 13 μg/g, which leads to additional input of 80 thousand t/year of barium into the ocean, or 8,6% of its entry into the ocean without taking into account the transformation of runoff at the river-sea geochemical barrier. The assessment of the role of desorption processes in the transformation of dissolved barium runoff is in order of magnitude consistent with the data of field observations for most of the mouth areas of the world’s rivers.

The paper presents the results of experimental studies on the synthesis of carbide Fe₇C₃ at 5,5 GPa. It was found that carbide Fe₃C and several polytypes of carbide Fe₇C₃ are formed together with diamond when the system is cooled. It is believed that Fe₇C₃ carbide may be a component of the Earth’s inner core. The obtained results indicate that carbide Fe₇C₃ in the form of polytypic modifications under natural conditions could be formed at relatively low pressures at the stage of differentiation of the Earth.

The research object is the junction zone between the underwater Lomonosov ridge and East Siberian shelf. We intend to prove the absence of the strike-slip fault within this junction zone. The existence of the fault zone within this junction zone is still debatable. Formerly used geological and geophysical datawere unsufficient. To remove this ambiguity, seismological data obtained in neighboring areas was applied. Analysis of the earthquakes epicenters in the region showed that in cases of existence of such a fault zone, modern intraplate seismic activity should be certainly registered within its limits. The aseismicity of the junction zone between the underwater Lomonosov ridge and adjacent shelf areas clearly indicates the genetic unity exhisting between these tectonic structures.

Integrated mathematical model of the Barents and White seas LME is proposed as a tool for assessing natural risks and rational use of biological resources. The model includes the following main blocks (modules): a) oceanographic conditions and biological productivity; b) trophodynamics and fishery management; c) environmental and biota pollution; d) socio-economic development; e) assessment of environmental risks from marine activities. Integrated model was used for assessing: the hydrological variability, long-term dynamics of ecosystem productivity and fishing load on the most important commercial species of the Barents Sea. A new zoning of the Barents Sea taking into account the geomorphological and hydrological factors was performed under the guidance of academician G.G. Matishov. Maps of the simulated gross primary production in the Barents Sea for the second half of the 20th and first decade of the 21st centuries are presented. The energy balance in the Barents Sea ecosystem at the end of the 20th and the beginning of the 21st century was calculated by trophodynamic model. It is concluded that determination of the fishing load on populations should base on using ecosystem mathematical models instead of single-species models. To estimate the fishing mortality, it is necessary to take into account not only the spatial effects associated with the characteristics of the fishes' life cycle and the distribution of fishing load, but also the influence of climatic factors and inner-ecosystem interactions. The use of modern information technologies, both in the field of primary data analysis, and in the area of their generalization to diagnose past changes, makes it possible to better understand the consequences for the Barents and White seas LME of existing natural resource use plans, taking into account the experience (sometimes negative) of past years and the expected climatic changes.

The first data on the scale of the lateral movement of the sessile in the water column are obtained. It is established that the scale of the lateral movement of suspended matter in the coastal regions is 50-210 times greater than the vertical flow of matter to the bottom.

The study of the influence of cobra Naja oxiana cardiotoxins on the contractility of the rat papillary muscles and its rhythm-inotropic characteristics has that the presence of toxins induces a slight contractility decrease in the stimulation frequency range up to 0,1 Hz. In the stimulation frequency range from 0,1 to 0,5 Hz a positive inotropic effect is found. However, the positive inotropic effect is replaced by a negative one with further increase in the frequency up to 3 Hz. In the presence of cardiotoxins, the positive force-frequency relationship in the region of 1-3 Hz, characteristic of healthy rat myocardium, disappears and relationship becomes completely negative. L‑type calcium channel blocker nifedipine does not affect the changes induced by toxins, while a high concentration (10 mM) of calcium prevents the effects of cardiotoxins on the muscle. The results obtained show that the impairment of the force-frequency relationship occurs long before the development of irreversible damage in the myocardium and may be the first sign of the pathological action of cardiotoxins.

We examined HIV‑infected patients with different efficiency of immune system restoration during the course of antiretroviral therapy. The study showed that against the background of low CD4⁺ T‑cell counts, subject with a discordant immunologic response (patients with less than 350 CD4⁺ T‑cells per µl of blood after more than two years of treatment) develop a regulatory CD4⁺ T‑cell (T_reg) deficiency. Furthermore, in these patients, the immunodeficiency is accompanied by an increase in the T_reg frequency. Accumulation of regulatory T‑cells in the blood of HIV‑infected subjects with discordant response to the treatment indicates a high viability of this T‑cell subset.

The visually driven instrumental conditioning on a one monkey (Macaca mulatta) was conducted after single-dose cranial irradiation with high-energy protons. The monkey executed saccades toward the visual stimuli and then performed the movement with ipsilateral hand correspondingly to their location in a right or left visual hemifield. The rate of correct responses with dominant right hand exceeded the rate of such responses with left hand and decreased briefly two months after irradiation. Then a month later, the rate of correct right-hand responses returned to the level before irradiation. No significant dynamics was revealed for the rate of correct left-hand responses. The proton irradiation effect on right-hand responses suggests possible short-term disturbances in the eye-hand coordination for right handedness while the visual perception remains resistant.

The giant deer Arvernoceros verestchagini David, 1992, authochtonous species of the Early Pleistocene biota of North Black Sea area, is discovered in Crimea. The giant deer was a member of fossil fauna of vertebrates from the Pleistocene deposits of Taurida karst cave. According to biochronological data, this fauna is dated to 1,8-1,5 Ma.