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This paper discusses the results of siliceous microfossils studies performed in a “staircase” of four isolation basins (33.7 m–2.9 m a.s.l.) on Big Solovetskiy Island (Solovki Archipelago, the White Sea). Diatoms were used as a primary group for paleoinferences, while chrysophyte cysts and sponge spicules also demonstrated high indicative potential. In all study lakes, the siliceous microfossils stratigraphy revealed three main stages of their evolution, i.e. large-basin, transitional and small-lake stages, each characterized by certain composition of the diatom assemblages and floristic diversity, relative abundances of chrysophyte cysts and sponge spicules, and siliceous microfossils concentrations. In the uppermost lake, glaciolacustrine environments unfavorable for aquatic biota existed during the large-basin stage. The proglacial lake stage terminated prior to ca. 10.4 cal ka BP, followed by a (semi)terrestrial episode before the transition to small-lake environments. In the other three lakes, marine environments were inferred at the earlier stage, characterized by the predominance of marine and brackish-marine diatoms, increased proportions of sponge spicules and low “cysts to diatoms” ratio. At the transitional marine-freshwater stage, mass growth of small fragilarioid diatoms and decreased abundances of spicules indicated unstable environments, while increased proportions of cysts pointed to progressive freshening of the basins. The duration of the marine-freshwater transition expectedly prolonged from ca. 200 yr in the upper basin (16.6 m a.s.l) to ca. 500 yr in the lowermost lake (2.9 m a.s.l.). The isolation from the sea took place between ca. 6.3 and 1.4 cal ka BP. At the small-lake stage, siliceous microfossils stratigraphies reflected local specifics of the basins and their catchments. We argue that besides traditionally used diatom data, relative and absolute abundances of siliceous microfossils also possess high indicative value for isolation basin studies. Our study demonstrated that marine waters on Big Solovetskiy Island never reached ca. 34 m a.s.l. during the Holocene, unlike the western coast of the Onega Bay where the Preboreal marine intrusion was recorded even at higher elevated localities. Different rates and amplitudes of shoreline displacement are thus suggested for the inner and outer parts of the Onega Bay. During the mid-Holocene Tapes transgression, before ca. 6.3 cal ka BP, the relative sea level on Big Solovetskiy Island exceeded 17 m a.s.l. The average estimated rates of the shoreline retreat during the second half of the Holocene gradually decreased from 0.28 cm year−1 to 0.2 cm year−1, indicating slowed isostatic uplift.

One of the key directions for the development of commercial solid oxide fuel cells fuelled by natural gases consists in the search for efficient fuel electrode materials operated under hydrocarbon-containing atmospheres. Within the present work, we synthesized and characterised novel composites based on a double-perovskite Sr2Ni0.75Mg0.25MoO6–δ phase and a second phase comprised of SrMoO4 or NiO. For these composite materials, the reduction behaviour, tolerance to carbon dioxide and catalytic activity towards the partial oxidation of hydrocarbons mixture were comprehensively studied. It is shown that the target properties of the designed composites are affected not only by the type of catalysts but also by the method of their preparation. According to the presented results, the most appropriate materials are composites containing 20 wt% SrMoO4 or 50 wt% NiO.

The significant role of the unavoidable hot water treatment during laser ablation of lead in water in formation of the nonspherical 2D (plates) and 3D micro- and nanoparticles (octahedra and rods) in suspension and at the target surface has been shown experimentally. The formation of the nonspherical particles has been demonstrated at hot water treatment alone at temperature above 70 °C achieved frequently during laser ablation in water. The simple model was applied for explanation of the obtained formation of 3D particles. The 2D plates formed by seedless growth. The influence of the unavoidable hot water treatment should be considered as an additional mechanism for explanation of the formation of the nonspherical nanoparticles during laser ablation in water.

The main aims of adaptation mechanisms of heart contractility are to regulate the stroke volume and optimize the global heart function. These mechanisms manifest themselves in hearts of healthy animals and in hearts with severe hypertrophy in different ways. Severe right ventricle hypertrophy was induced by single treatment with monocrotaline. Young rats of both sexes were used to prevent influences of sex hormones on the development of right ventricular hypertrophy. Serial duplex method is used as a model of interaction of two ventricular wall segments. In serial duplex the muscles are in connection 'end-to-end' and subjected to mutual deformations during contractions. It is important to establish the fine-tuning phenomena and evaluate their expressiveness in healthy hearts and hearts with severe hypertrophy. Mild force transient processes occur on muscle connection to serial duplex and on muscle separation from duplex in all experimental groups. These transients manifest themselves as slow changes in the amplitude of muscle contraction from cycle to cycle. During the muscle interaction in the serial duplex, evident transient processes in the mutual amplitude of deformations in all experimental groups are observed. The greatest changes in the length occur in the relaxation phase of the contraction cycle. The loss of interaction between ventricular muscles of rats with severe heart hypertrophy is the most likely cause of an additional deterioration in the heart pumping function. New targets may occur for the recovery of contractility of hearts with severe hypertrophy.

Composite materials (1 − f) CaWO4 – fSiO2 with volume fraction of SiO2 f ≤ 1.0 were prepared by the solid state method. The obtained composites have been examined by SEM-EDS, the electrochemical impedance technique, conductivity measurements versus oxygen partial pressure and EMF measurements in order to evaluate ion transport numbers. It was shown that heterogeneous doping of the poor oxygen ion conductor CaWO4 with nano-SiO2 even at low concentration (f

This investigation continues our study of the effects of Pb-Cd poisoning on the heart, extending the enquiry from isometric to auxotonic contractions, thereby examining the effect on the ability of myocardial tissues to perform mechanical work. Different shifts were revealed in myocardial force-velocity relations following subchronic exposure of rats to lead acetate and cadmium chloride acting separately, in combination, or in combination with a bioprotective complex (BPC). The experiments were conducted on isolated preparations of trabecules and papillary muscles of the right ventricle in physiological loading conditions and on isolated heart muscle contractile proteins examined by the in vitro motility assay. The results of the latter correlate with the shifts in the ratio of cardiac myosin isoforms. The amount of work performed by the myocardium was calculated on the basis of the tension-shortening loop area and was found to be similar in the preparations from all experimental groups. This fact presumably reflects adaptive capacity of the myocardial function even when contractility is damaged due to the metallic intoxication of a moderate severity. Some characteristics of rat myocardium altered by the impact of lead-cadmium intoxication became fully or partly normalized if intoxication developed against background administration of a bioprotective complex (BPC). Together with previously reported results obtained in the isometric mode of contractility, all these results strengthen the scientific foundations of risk assessment and risk management projects in the occupational and environmental conditions characterized by human exposure to lead and/or cadmium.

A significant improvement in the sintering of Ho2O3 powders obtained by self-propagating high-temperature synthesis as a result of the addition of lanthanum oxide was made. It was found that the addition of 5% lanthanum oxide slightly affects the Verdet constant value (which is ~1.3 times higher than the corresponding value for terbium-gallium garnet, and is similar to the value for terbium-aluminum garnet ceramics), but significantly increases the transparency of ceramics. Samples of 5% La:Ho2O3 magneto-optical ceramics with a transmission of up to 76% at a wavelength of 1 μm at a thickness of 1 mm were obtained. Such La:Ho2O3 ceramics have transparency windows in the ranges of 0.93–1.06, 1.3–1.6 and 2.2–7 μm, what distinguishes them from materials containing Tb3+ ions, that are opaque in these ranges. It is shown that La:Ho2O3 ceramics have relatively high mechanical characteristics (HV = 8.4 GPa, E = 182 GPa, KIC = 0.95 MPa m0.5) which vary slightly depending on the lanthanum oxide concentration.

Weakly agglomerated nanoparticles of (Ho 1-x La x ) 2 O 3 solid solutions were synthesized with the help of a self-propagating high-temperature synthesis (SHS). The nanopowders were studied by a simultaneous thermal analysis (TG-DSC), X-ray diffraction (XRD), BET and FT-IR spectroscopy methods. Changes of the particles morphology after annealing at different temperatures and ball milling were investigated by a scanning electron microscopy (SEM) and a dynamic light scattering (DLS) method. It was found that annealing at a temperature of 900 °C in air and ball milling of the SHS nanopowders allow obtaining rounded shape particles with a mean diameter of about 20 nm and C-type cubic crystal structure. Up to 10 mol.% of the lanthana was shown to dissolve in the holmium oxide nanoparticles. © 2019 Russian Science Foundation: 18-13-00355 This work was supported by the Russian Science Foundation (research project No. 18-13-00355 ).

Multidisciplinary studies conducted in Russian Karelia substantiated the existence of a major Baltic-Ladoga waterway in the Karelian Isthmus that emerged ca. 9500 cal BCE, and remained in action for ca. 7000 years. The predominant location of prehistoric sites in the catchment area indicates that this waterway effectively controlled the movements of hunter-gatherer groups during the greater part of the Holocene. A general increase of population density and sedentary behaviour, signalled by the beginning of intensive pottery-making at ca. 5560–5250 cal BCE, occurred in an environment of increased biodiversity and the establishment of mixed boreal – broad-leaved forests observable in the pollen records. The transgression of Lake Ladoga reached its peak between 1500 and 1000 BCE, resulting in the breakthrough of the Neva River and a general fall in the water level of the Ladoga-Volkhov-Ilmen hydrological system. The availability of low-lying fertile soils stimulated the rapid expansion of agriculture, recognized by the occurrence farming-related pollen and changes in the sedimentation, resulting in the rapid spread of farming communities.

Newly obtained pollen and diatom data controlled by radiocarbon measurements shed new light on the connection of the Ladoga Lake with the Baltic Sea via a strait on the Karelian Isthmus. It emerged ca. 11,500 cal BP, and remained in action for ca. 7000 years, forming a major waterway for early human migrations. The transgression of the Ladoga Lake started ca. 5000 cal BP and reached its maximum ca. 3000 cal BP (ca. 1100–1000 cal BC). The formation of a new outlet via the Neva River led to a rapid regression of the lake that stimulated the spread of farming populations.

Spatially nonuniform imprint behavior induced by X-ray synchrotron, electron and neutron irradiation has been investigated in sol–gel Pb(Zr,Ti)O3 thin films. The analysis of the switching current data reveals the strong influence of irradiation on the switching current shape. The obtained effects have been explained as a result of acceleration of the bulk screening process induced by irradiation. It was shown that the spatial distribution of the internal bias field is determined by the domain structure existing during irradiation. The changes in the structural characteristics during fatigue cycling have been reveled by high resolution synchrotron X-ray diffraction experiments on (1 1 1)-oriented PZT-based capacitors with a composition in the morphotropic region. From both ex situ and in situ measurements, microstructural changes with cyclic switching during fatigue have been evidenced and correlated with the evolution of the switching characteristics. © 2005 Published by Elsevier B.V.

The dephasing kinetics of the higher frequency component of the Fermi-resonance dyad ν 1 /2ν 2 (1388 cm −1 ) of CO 2 was studied by means of time-domain CARS in the density range where spectral exchange and Dicke effect play a noticeable role. The spectral exchange manifests itself in the gradual shift to longer delay times of minima and maxima of the beats between different Q -branch components with increasing densities and in the simultaneous beats smoothing. As a result of both the effects, the pulse response was practically exponential at CO 2 densities ⩾ 0.4 Amagat.

The interference of two beams of squeezed light can produce the“squeezed vacuum”.

The theory of the globular state and the coil-globule transition has been constructed for a persistent macromolecule. The reasons for the universality of the picture of this transition have been explored (its independence from the microscopic characteristics of the polymer). A method of seeking the parameters of the bead model equivalent to a given persistent chain is indicated. A way of evaluating the axial ratio of the macromolecule (ratio of the persistent length l to the thickness d from the experimental data on the coil-globule transition has been found. In cyclohexane and dioctylphthalate l/d≈-2 has been found for PS. The orientation ordering of portions of the chain in the surface layer of the globule is analysed numerically.

An optical scheme is proposed for the reconstruction of the phase distribution of the light field from two amplitude distributions. A mathematical algorithm is developed, which models the operation of the scheme. Numerical calculations revealed the rapid convergence of the algorithm.