bluuebunny/crossref_metadata_2025 huggingface dataset:
EARLY POSTNATAL EXPERIENCE MODIFIES ACTIVATION OF THE PITUITARY-TESTICULAR COMPLEX IN MALE HOUSE MICE (MUS MUSCULUS) EXPOSED TO THE ODOR OF RECEPTIVE CON- AND HETEROSPECIFIC FEMALES
Authors: Kotenkova E. V. , Kuznezova E. V. , Maltsev A. N. , Ambaryan A. V.
Published: April 2024

For the first time, data were obtained proving the modification of the activation of the pituitary-testicular complex of male house mice under the influence of early postnatal experience and the maternal environment when exposed to the odor of receptive females of their own and closely related species. We have confirmed the conjugacy of the formation of behavioral and physiological mechanisms of precopulatory isolation in early ontogenesis. The serum level of free testosterone in males of closely related species M. spicilegus and M. m. wagneri differ, it is significantly lower in mound-building mice. The level of free testosterone of males fostered by a conspecific female was significantly lower when they exposed a heterospecific in comparison with a conspecific female odor. The rearing of M. m. wagneri males by females of a closely related species caused a decrease in the testosterone response of males to the exposure of chemosignals from a female (both con-and heterospecific) and led to the absence of differences in the serum level of free testosterone when they exposed to the odor of a female of their own or closely related species. The data obtained indicate a significant influence of the rearing conditions on the formation of hormonal mechanisms of reproductive isolation.
AUTUMN MIGRATION OF THE GREATER NOCTULE BAT (NYCTALUS LASIOPTERUS): ACROSS COUNTRIES AND MOUNTAINS TO A NEW RECORD FOR THE RANGE OF SEASONAL FLIGHTS OF BATS
Authors: Vasenkov D. A. , Vasiliev N. S. , Sidorchuk N. V. , Rozhnov V. V.
Published: April 2024

For the first time, using GPS-GSM trackers, long-term seasonal flights of greater noctule bat (Nyctalus lasiopterus) from summer habitats in Russia to wintering areas in Europe have been recorded. One of the seasonal migratory flights is a record distance for bats (2515 km). The maximum daily flight was 445 km. One of the animals abruptly changed the direction of migration from southwest to north on the third day of flight after crossing the Kursk magnetic anomaly.
SOURCE AGE OF METATERRIGENIC ROCKS FROM THE LESHCHEV ZONE OF THE MIDDLE VOLGA MEGABLOCK IN THE VOLGA-URAL SEGMENT OF THE EAST EUROPEAN CRATON
Authors: Anosova M. O. , Astrakhantsev O. V. , Postnikov A. V. , Kirnozova T. I. , Sabirov I. A. , Fedotova A. A. , Fugzana M. M. , Zueva O. A.
Published: April 2024

Biotite-garnet-sillimanite-cordierite gneisses from the Leshchev zone of the Middle Volga megablock in the Volga-Ural segment of the East European craton have been studied. The obtained Sm-Nd model age of the rocks is 2.8 Ga. U–Pb isotope-geochronological study of zircon cores from these rocks was carried out. The CL images revealed several generations of the zircon cores. The obtained age of the main sources of detrital zircon is 2.58 Ga. Single zircon grains have ages of cores of 2.4, 2.7, and 3.1 Ga. The calculated ɛNd(2500) = = –0.6 indicates the crustal or mixed mantle-crustal nature of the protolith of these gneisses. High-alumina metaterrigenous rocks of the Bolshecheremshanskaya Group, the Leshchevskaya zone, and the South Volga supracrustal complex are considered as elements of time and spatial secuence of sediments of Neoarchean and Paleoproterozoic basins with a protoplatform base and a passive continental margin, successively replacing each other.
STUDY OF THE MULTIFRACTALITY OF GEOMAGNETIC VARIATIONS AT THE BELSK OBSERVATORY
Authors: Riabova S. A.
Published: April 2024

The study of the dynamics of periodic variations with periods from 1 to 27 days using the wavelet transform and scaling analysis by the method of maxima of the modules of the wavelet transform coefficients is carried out using the results of instrumental observations of the geomagnetic field performed at the Belsk Central Geophysical Observatory in 2008 and 2018 (low solar activity) and in 2014 (high solar activity). A change in the intensity of periodic variations is established. Close to monofractal nature of diurnal geomagnetic variations is shown. The 27-day variation and its harmonics have a higher degree of multifractality during solar activity maximum compared to solar activity minimum.
FEATURES OF THE STRUCTURE AND EVOLUTION OF THE LOWER PARTS OF THE CONTINENTAL CRUST OF THE YAKUTIAN DIAMONDIFEROUS PROVINCE IN THE AREA OF THE UPPER-MUNA KIMBERLITE FIELD
Authors: Shatsky V. S. , Ragozin A. L. , Wang Q. , Su W. , Ilyin A. A. , Kolesnichenko M. V.
Published: April 2024

Upper Muna kimberlite field) showed that the crust at different levels is composed of pyroxene, garnet-pyroxene crystalline schists and garnet-pyroxene gneisses. Exsolution textures in pyroxenes and amphiboles, granat rims around grains of ilmenite and pyroxenes indicate that the mineral associations of crystalline schists were formed during cooling at constant pressure. Р–Т equilibrium parameters indicate that garnet-pyroxene crystalline schists are present in the middle crust (P = 7–8 kbar), while garnet-pyroxene gneisses can be considered as rocks of the lower crust (P = 9–10.1 kbar). For the first time, sodalite was found in xenoliths of crystalline schists, which indicates the presence of brines with a high concentration of NaCl at the final stages of rock cooling. The determination of the U–Pb age of zircons testifies to the Neoarchean (2.7 Ma) tectono-thermal event, accompanied by the melting of the crust. In the garnet–pyroxene gneisses, the 1.9 stage is weakly manifistated. The obtained data confirm the earlier conclusion about the vertical and lateral heterogeneity of the crust of the Yakutsk diamondiferous province and the absence of dependence between the degree of crust reworking and spatial location relative to the main collision zones of the Siberian craton.
TWO STAGES OF ASSEMBLY OF THE PANGEA SUPERCONTINENT IN THE POLAR URALS: FIRST U/Pb (LA-ICP-MS) AND 40Ar/39Ar AGES OF THE YARKEU COMPLEX
Authors: Sobolev I. D. , Novikova A. S. , Vikentyev I. V. , Sheshukov V. S. , Dubensky A. S. , Travin A. V. , Varlamov D. A. , Bortnikov N. S.
Published: April 2024

In the Polar Urals, there are few small granitoid intrusions (Yarkeu, Yayu and Pogurei complexes), which are usually associated with the Ural collision. Their Carboniferous-Early Permian age, in most cases, is based on methodologically outdated K/Ar dates, and is also assumed from field geological relationships. We have studied the monzonitoids of the Yarkeu petrotypical pluton, one of the largest such intrusions, and for the first time obtained Late Precambrian U–Pb LA-ICP-MS (zircon) and 40Ar/39Ar (amphibole) ages of 687 ± 3, 669 ± 8 Ma years, respectively. Water-saturated fluid regime (presence of magmatic amphibole and high water content in it, 4.5–5.6 wt %,), hypabyssal formation conditions (P = 2.1–3.5 kbar, T = 871–960°C), features of the chemical composition of monzonitoids (low TiO2 (0.6–0.8 wt %) and CaO (3.6–6.3 wt %) contents, high Al2O3 (16.6–18.0 wt %) and K2O (1.7–4.6 wt %), enrichment in large-ion lithophile elements relatively high field strength and rare earth elements, Ta-Nb minimum and Pb maximum), as well as metallogenic specialization in Cu and Mo (±Pb, Hg, Au), indicate the formation of the rocks of the Yarkeu complex in a subuction-related setting in a fairly thick continental crust. Isotopic clocks in these monzonitoids captured two stages of the assembly of the Pangea supercontinent: the earliest stage in the Late Precambrian, when monzonitoids were formed on the active Bolshezemel margin of Arctida, and one of the final stages in the Middle to Late Carboniferous, when the rocks underwent metamorphism due to the closure of the Paleo-Ural ocean and the onset of collision between Arkt-Laurussia and Siberia.
ON THE INFLUENCE OF VISCOSITY ON THE DEVELOPMENT OF INSTABILITY IN ANOMALOUSLY STRATIFIED GEOSYSTEMS
Authors: Ryzhak E. I. , Sinyukhina S. V.
Published: April 2024

The paper investigates the question of the influence of viscosity on the rate of development of instability in heavy viscoelastic geosystems with an anomalous density distribution over depth. Geomaterials are considered as incompressible, and the Maxwell model of viscoelasticity (that makes it possible to adequately describe the dynamics of geosystems even in the case of huge viscosity of geomaterials) is adopted for them. Along with viscoelastic systems, the elastic comparison systems are considered, which are characterized by the same anomalous stratification and the same values of shear stiffnesses as the viscoelastic systems studied. Bilateral estimates for the increment of growth of the fastest mode of loss of stability (the “main increment of growth”) are obtained, which are valid for any viscosity. It has been found that the main growth increment always exceeds the main growth increment for the unstable elastic comparison system, which is determined by the inertial properties of the latter together with the degree of supercriticality of the parameters characterizing its unstable equilibrium state. As viscosity increases, the main growth increment for the viscoelastic system tends from above to the corresponding increment for the unstable elastic comparison system. In the case of stability of elastic comparison systems, the corresponding viscoelastic systems are unstable, but the rate of development of their instability is very low due to the great viscosity of geomaterials. Precisely and only in the case of stability of comparison systems, the viscosity slows down this rate, and for geosystems with extremely great viscosity, the manifestation of their instability during real observation times is very small. The analysis carried out confirms the fact that the study of stability and instability of elastic comparison systems can serve as a methodological basis for studying stability and instability of viscoelastic geosystems.
SPATIAL DISTRIBUTION OF AMPLITUDES OF INTERNAL TIDAL WAVES ON THE NORTH-EASTERN SHELF OF SAKHALIN
Authors: Rouvinskaya E. A. , Kurkina O. E. , Kurkin A. A.
Published: April 2024

The transformation of a multicomponent barotropic tide in the Sea of Okhotsk is considered in the framework of fully nonlinear non-hydrostatic calculations. The data of the tidal model and parameterized bottom topography and vertical profiles of sea water density based on data from open international atlases are used to initialize the model. Estimates of the wave amplitudes of the diurnal and semidiurnal baroclinic tides in terms of the displacement of isopycnal surfaces at different horizons are obtained and presented in the form of geographical maps. It is shown that the distribution of amplitudes significantly depends on depth, has a complex spatial structure with a noticeable predominance of the amplitudes of baroclinic waves of the diurnal period and the main extrema located on the shelf opposite Cape Elizabeth, Okhinsky Isthmus and Cape Patience. The implemented approach to mapping the amplitudes of internal tides can be applied to other shelf areas of the seas of the Russian Federation and used for predictions of these phenomena, including engineering assessments for the design and operation of marine infrastructure.
HETERO- AND HOMOGENEOUS STATES OF HYDROCARBON FLUIDS IN THE EARTH’S INTERIOR (FROM THE DATA OF THE STUDY OF SYNTHETIC FLUID INCLUSIONS)
Authors: Balitsky V. S. , Setkova T. V. , Balitskaya L. V. , Golunova M. A. , Bublikova T. M. , Plotnikova I. N. , Aranovich L. Ya.
Published: April 2024

We performed the experimental study combined with in situ investigations of the phase composition and states of water-hydrocarbon fluids in synthetic inclusions in quartz. Thermometric data indicating of heterogeneous state of fluids at shallow, medium and large depths of oil and gas strata were determined. It has been shown that even at depths up to 10–12 km at temperatures of 250–290°С, water-hydrocarbon fluids with an oil content of 10 or more vol. % retain a heterogeneous state. Homogenization in such fluids, as have shown experimentally, is achieved at temperatures above 380–400°C only. However, such temperatures have not yet been detected in any of the real oil and gas basins of the world. The results of performed study allow predict the future discovery of homogenous oil and other hydrocarbon deposits.
THE KEY SECTION OF THE VALDAIAN PEAT BOG AS A SOURCE OF PALEOECOLOGICAL AND PALEOCLIMATIC INFORMATION
Authors: Tishkov A. A. , Gracheva R. G. , Konstantinov E. A. , Samus A. V.
Published: April 2024

A paleoclimatic reconstruction of the last 14 ka years was carried out based on the results of GPR sounding, spore-pollen analysis and radiocarbon dating of a peat section (7 m) located in a model bog of the Valdaisky National Park (Novgorod Region). Peat accumulation rates varied from 0.075 mm per year during the Late Glacial to 0.15–1.15 mm per year during the Boreal stage (when the levels of the Valdaian lakes dropped 10 m) and 4.25 mm/year in recent centuries. Numerous cycles of Holocene warming/cooling events were within ±1–2°C compared to the current ones and were accompanied by moderate fluctuations in annual precipitation (±25–50 mm). The greatest amount of forest compositional change took place during the Atlantic period, when spruce–broad-leaved forests and oak forests dominated. In the last two millennia, the vegetation dynamics of the region were mainly influenced by agricultural activity.
GEOPHYSICAL EFFECTS OF THE ACTIVE STAGE OF THE STROMBOLI VOLCANO ERUPTION ON OCTOBER 9, 2022
Authors: Spivak A. A. , Loktev D. N. , Rybnov Yu. S. , Riabova S. A. , Tikhonova A. V.
Published: April 2024

Using the results of instrumental observations carried out in the surface atmosphere, the response of the microbaric background, variations of the Earth’s magnetic and electric fields to the paroxysmal activity of the Stromboli volcano (October 9, 2022, Italy) is analyzed. It is shown that the active stage of a volcanic eruption was accompanied by the generation of an acoustic signal and pronounced variations in the geomagnetic and atmospheric electric fields at considerable distances both during the period of volcano activity and during the arrival of an infrasonic wave at the observation point. It was also noted that the volcanic eruption caused a response in the ionosphere in the form of a change in the critical frequency of the F2 layer.
TERRIGENOUS ROCKS OF THE KODAR GROUP IN THE UDOKAN SUBZONE OF THE KODAR-UDOKAN TROUGH, THE ALDAN SHIELD: AGE, SOURCES, AND PROVENANCE AREAS
Authors: Adamskaya E. V. , Kovach V. P. , Kotov A. B. , Tolmacheva E. V. , Plotkina Yu. V. , Skovitina T. M. , Fedossenko A. M. , Gorovoi V. A.
Published: April 2024

The article presents the results of U–Th–Pb (LA-ICP-MS) geochronological studies of detrital zircon from metasandstones of the Kodar Group of the Udokan Complex, the Aldan Shield. It has been established that the Kodar Group of the Udokan subzone of the Kodar-Udokan trough have an age of 2.08–2.05 Ga. The sources of the Kodar Group deposits were the Archean (ca. 2.65, 2.83, and 3.23 Ga) igneous and metamorphic complexes of the Chara-Olekma geoblock of the Aldan Shield and the adjacent areas of the Stanovoi suture zone, as well as unidentified on the present erosion level the Paleoproterozoic (ca. 2.08 Ga) island arcs or active continental margin complexes that existed in the southern frame of the Archean Chara-Olekma geoblock. It is assumed that rocks of different ages, belonging both to the Kodar Group of the Udokan Complex and to the metamorphic complexes of the Stanovoi suture zone, can be tectonically juxtaposed in the southern part of the Udokan subzone of the Kodar-Udokan trough.
FIRST FIND OF THE FROZEN MUMMY OF THE FOSSIL DON HARE LEPUS TANAITICUS (LEPORIDAE, LAGOMORPHA) FROM THE PLEISTOCENE OF YAKUTIA
Authors: Boeskorov G. G. , Chernova O. F. , Shchelchkova M. V.
Published: April 2024

Until recently, only the bone remains of the Don hares, extinct in the Holocene, were known. For the first time, the mummy of an adult hare, identified as the Don hare, has made it possible to expand the understanding of this species and its morphological adaptations to living conditions in the Arctic steppes of the Pleistocene of Yakutia: large body length, short ears and feet, powerful locomotor apparatus of the hind limbs, hard hair brushes on the feet, excellent heat-shielding properties of the fur, including the specific microstructure of the hairs.
DIMENSIONAL EFFECT AND CRYSTALLOMORPHOLOGICAL FEATURES OF GIBBSITE IN THE BAUXITE-BEARING WEATHERING CRUST
Authors: Boeva N. M. , Bortnikov N. S.
Published: April 2024

Using the example of the Central Chadobets uplift deposit, the relationship of the crystallomorphological features of gibbsite with its position in the bauxite-bearing profile of the weathering crust is revealed. From the down up, in various parts of the profile, as a result of infiltration metasomatosis and various physico-chemical conditions, there is an increase in free space, contributing to the growth of gibbsite crystals. The higher the rock lies, the more porous it is. Thus, in the down-up section, the size of gibbsite crystals increases, its morphology becomes more complicated. By the method of thermal analysis, it was found that the larger the size of the gibbsite crystals, the more boehmite is formed when it is heated. These conclusions will help technologists to choose the most rational scheme for processing bauxite.
THE FIRST MANGANITE CRUSTS IN THE SEA OF JAPAN
Authors: Kolesnik O. N. , Karabtsov A. A. , S’edin V. T. , Kolesnik A. N. , Terekhov E. P.
Published: April 2024

Manganese crusts composed of manganite with an admixture of pyrochroite and quartz are revealed for the first time for the Sea of Japan. According to the combination of features, these are low-temperature hydrothermal mineral formations appeared on the slope of the South Yamato Ridge at a depth of no more than 1300 m under conditions of oxygen deficiency.
U-Pb ID-TIMS AGE OF RUTILE FROM THE NORTH MUYA BLOCK ECLOGITES (NORTHEASTERN TRANSBAIKALIA) AS A TRACER OF DURATION FOR OF THE CONTINENTAL LITHOSPHERE EXHUMATION
Authors: Skuzovatov S. Yu. , Rizvanova N. G. , Skublov S. G. , Shatsky V. S.
Published: April 2024

Being an abundant mineral phase of high-grade rocks, rutile is used as a tracer of lithospheric evolution for deep zones of orogenic belts. This study presents the new ID-TIMS U–Pb geochronological, mineralogical and geochemical data for rutile from the North Muya block (Baikal-Muya Foldbelt) eclogites in order to examine the applicability of its age estimates relative to the exhumation process of high-grade rocks. The assemblage of mineral inclusions in rutile (mainly titanite, epidote and amphibole) indicate rutile growth through titanite breakdown reactions during prograde metamorphism epidote-amphibolite or amphibolite-facies rocks. The range of Zr contents and estimated Zr-in-rutile crystallization temperatures correspond to conditions from prograde (619–638°С at 1.5 GPa) till peak ones (659–684°С for 2.5 GPa). The U–Pb age estimate (604 Ma) is notably younger than that of peak eclogitic metamorphism (630 Ma), and highlight the protracted cooling history of eclogite-bearing complex during its evolution below closure temperature of the U–Pb isotope system (~500–525°С) during tectonic unroofing or erosion of continental complexes.
LATE QUATERNARY COUNURITE DRIFTS ON THE KARA SEA SHELF
Authors: Baranov B. V. , Ambrosimov A. K. , Moroz E. A. , Mutovkin A. D. , Sukhikh E. A. , Dozorova K. A.
Published: April 2024

Contourite drifts were for the first time detected on the SW Kara Sea shelf basing on аnalysis of bathymetry and seismoacoustic data obtained in RV “Akademik Nikolay Strakhov” cruises 41 (2019) and 49 (2020). The drifts are confined to narrow nearly NS-striking depression with depth reaching 240 m. They are separated from underlying sediments by basal unconformity, conditioned by origination of bottom current in marine environment after Barents-Kara shield melting during Late Plestocene – Holocene. Hydrological measurements performed during Cruise 89–1 of RV “Akademik Mstislav Keldysh” (2022) shows existence of bottom current with measured velocity up to 10 cm/s.
RELEVANCE OF RECEIVER FUNCTION TECHNIQUE IN SUBDUCTION ZONE (AVACHA BAY)
Authors: Goev A. G. , Reznichenko R. A. , Aleshin I. M.
Published: April 2024

This paper elaborates on specific aspects of P- and S-receiver functions. The functions that are researched in this paper were calculated using waveforms obtained by three adjacent broadband seismic stations within the Avacha bay area in proximity to the subduction zone of the Pacific plate. The subduction zone in seismological context manifests as a layer of high seismic velocities, which are known to introduce a level of distortion to the receiver functions. To specify the level of this effect we parsed through two sets of P and S receiver functions in this research. The first set contains events that pass through and theoretically are affected by the subduction zone of the Pacific plate and the second set contains events that do not. The paper demonstrates that converted waves and their multiples formed at the boundaries of the high-velocity layer significantly affect P-receiver functions starting with 30-th second after the primary phase. However, no notable effects on S-receiver functions were revealed. Thus, we empirically confirm that [at least in the investigated area] local single-dimensional models are valid to be used for the inversion of the receiver functions to the depth of up to 200 km after which point the seismic noise produced by the subducting plate effectively limits the applicability of such models.
MONITORING OF CADMIUM CONTENT IN AGROECOSYSTEMS OF CENTRAL CHERNOZEM REGION OF RUSSIA
Authors: Lukin S. V.
Published: April 2024

As part of the implementation of the state program of agroecological monitoring, the content of Cd in the main components of the agroecosystems of the forest-steppe zone of the Belgorod region, which is located in the south-west of the Central Black Earth region, was studied. The soil cover was mainly represented by leached and typical chernozems. During the studies, it was found that in the layer of 0–20 cm of arable black soil leached, the average gross content of Cd is 0.32, the concentration of mobile forms is 0.08 mg/kg, which corresponds to background values and significantly below the level of APC. The excess of background concentrations of this element was found in the soils of roadside ecosystems at a distance of up to 60 m from the roadbed. The main amount of Cd enters the agroecosystems of the Belgorod region with organic fertilizers, but this does not pose a danger to soil contamination and crop production. Of the crops studied, the minimum amount of this element is contained in the white lupine grain (0.011 mg/kg), and the maximum amount is contained in sunflower seeds (0.086 mg/kg). The average Cd content of corn, barley and winter wheat grains did not differ significantly and ranged from 0.037 to 0.042 mg/kg. In clover and alfalfa hay, the average content of this metal was almost the same as 0.012–0.013 mg/kg, which is significantly lower than in natural forbs (0.045 mg/kg). In the studied crop production, there was no excess of MAC Cd levels for food grains and MAL for feed.
PERTURBATIONS FAR FIELDS OF THE INTERFACE SURFACE OF THE DEEP OCEAN AND THE ICE COVER FROM LOCALIZED SOURCES
Authors: Bulatov V. V. , Vladimirov I. Yu. , Morozov E. G.
Published: April 2024

The problem of far wave fields arising at the interface between ice and an infinitely deep homogeneous liquid in the flow around a localized source of perturbations is solved. An integral representation of the solution is obtained and, using the stationary phase method, an asymptotic representation of the solution is constructed for various modes of wave generation. Numerical calculations show that with a change in the flow velocities and ice thickness, a noticeable qualitative rearrangement of the phase patterns of the excited far wave fields at the interface between ice and liquid occurs.
FEATURES OF THE FORMATION OF HIGH STRONTIUM CONCENTRATIONS IN DRINKING GROUNDWATER NEAR THE SEA COAST
Authors: Malov A. I.
Published: April 2024

Estimates of strontium concentration factors in groundwater have been carried out in various regions of the world, however, as a rule, analyzes and interpretations were carried out for the entire set of hydrochemical data, without separating water samples with high and low strontium content. Therefore, correlations were often approximate. This study summarizes a new approach to the use of non-traditional tracers, including carbon and uranium isotopes, to study areas that are promising for drinking water supply. Water samples were divided into two clusters according to the content of strontium: 1) more than 7 mg/l, 2) less than 7 mg/l, and the goal was to understand the features of the formation of Sr concentrations for each cluster separately. It was found that in the samples of the first cluster there is a high correlation of Sr and total mineralization, along with a correlation of Sr with SO\(_{4}^{{2 - }}\), which may be due to high concentrations of Sr in carbonates with a high content of gypsum and celestite. The dedolomitization processes and the presence of reducing conditions in aquifers also have an effect. An increase in Sr concentrations due to upwelling of brackish water is not confirmed. In samples from the second cluster, low concentrations of Sr are associated with oxidative conditions in aquifers. No correlation was found between Sr and total mineralization due to low and discrete concentrations of gypsum and celestite in carbonates. There was no effect of dedolomitization. The upwelling of brackish water, on the contrary, can have a significant effect on the increase in Sr concentrations.
MINERALOGY OF CONTINENTAL SEDIMENTS FROM THE ULAN-ZHALGA KEY SECTION (WESTERN TRANSBAIKALIA): RESPONSE TO QUATERNARY CLIMATIC CONDITIONS
Authors: Solotchina E. P. , Erbajeva M. A. , Shchetnikov A. A. , Kuzmin M. I. , Solotchin P. A. , Zhdanova A. N.
Published: April 2024

We present the results of studying the material composition of Quaternary subaerial-slope sediments of the new key section Ulan-Zhalga (Western Transbaikalia) with a thickness of about 30 m. The research methods include X-ray diffractometry (XRD), infrared spectroscopy, laser grain size analysis, elemental analysis. Quartz, feldspar, clay minerals, carbonates, hematite and traces of amphibole were found in the mineral composition of the studied sediments. For the first time the composition and structure of carbonate minerals were shown as a reliable indicator of climatic changes in the Pleistocene and Holocene for the subaerial section. For correct identification and determination of quantitative ratios of carbonates the mathematical modeling of their XRD patterns by the Pearson VII function was used. It has been established that the structure of the section involves two thick sequences differing in lithological and mineralogical features corresponding to two major stages of sedimentation. The lower sequence was formed under conditions of moderate wind activity and relatively high humidity as evidenced by the widespread development of soil horizons and the presence of low-Mg carbonates. The upper sequence, formed under colder and drier conditions with increased dynamics of aeolian processes is characterized by the presence of calcite, high-Mg calcite and excess-Ca dolomite.
DRINKING WATER QUALITY IN THE DON DELTA IN THE LACK OF WATER CONDITIONS
Authors: Matishov G. G , Grigorenko K. S.
Published: April 2024

Lack of water and regulation of the Don river runoff led to an irreversible transformation of natural hydrological and hydrochemical processes. At the end of 2022, despite of the shortage of river water, the region began laying a water pipeline to the Donbass, with a capacity of up to 300,000 cubic meters of water per day. Are there enough reserves of water resources for ever-increasing economic needs, throughout the year? The work is based on a targeted study of the chemical composition of water under different regimes and sea levels on the Taganrog coast of the Don Bay and Delta. The experiment covers the period from December 2, 2022 to January 30, 2023, and separate measurements, for comparison, on February 21; 30.03; 17.04.2023. Summary, three types of ionic composition were distinguished, which characterizes the Svinoe arm of the Don delta. Marine - with dominance (more than 80%) of summary amount of sodium and potassium ions, chlorides and salinity up to 7–9 g/L. The Don waters correspond to low mineralization (less than 2 g/l), an increased proportion of Na+ + K+ (50–60%), a close amount of SO\(_{4}^{{2 - }}\) and HCO\(_{3}^{ - }\) (30–40% each). Since 2018, the presence of ground waters has been regularly recorded when the level decreases. There are brackish waters with a salt content of more than 5 g/L. They typically have a high content of sodium and potassium (more than 60%) and sulfate ions (60–80%). Monitoring shows, that the shortage of fresh drinking water will increase, and as its withdrawal increases, it will accelerate in time. It will be replaced (up to 5–7‰) with mineralized ground and Black Sea water. In what proportions will be pumped (redistributed by seasons) weakly brackish (2–4 g/L) and brackish (4–8 g/L) water into water pipelines remains to be explored.
ON THE POSSIBILITY OF ELEMENTAL ANALYSIS IN THE TASKS OF MONITORING MARINE AREAS USING ULTRASONIC SPARK SPECTROSCOPY
Authors: Bulanov A. V. , Krikun V. A.
Published: April 2024

The possibilities of detection and operational analysis of chemical elements in seawater using ultrasonic spark spectroscopy are demonstrated. The research was carried out with the help of a specially developed automated complex for spectral and hydrophysical studies, which was successfully tested for many days in expedition conditions Sea of Japan (cruise No. 81 of the R/V Professor Gagarinsky) and the Atlantic Ocean (cruise No. 52 of the R/V Academician Boris Petrov). New data have been obtained on the distribution of dissolved chemical elements and the state of seawater with high spatial resolution along long trails and at multi-day landfills in the Sea of Japan and in the Atlantic Ocean. The complex and the methods used can be recommended for in-situ studies of the state of natural water areas.
NORWEGIAN SEA HOLOCENE ENVIRONMENTS BASED ON THE FOSSIL MICROALGAE ASSEMBLAGES
Authors: Klyuvitkina T. S. , Novichkova E. A. , Matul A. G. , Kravchishina M. D.
Published: April 2024

Detailed micropaleontological analysis was performed on the sediment core AMK-6142 collected in the deep-sea southwestern part of the Lofoten Basin in the Norwegian Sea. Summer sea-surface temperature for the last 7 cal. ky was reconstructed from dinocyst assemblages using the modern analogue technique (MAT). Sea-surface temperature reconstruction and dinocysts species composition indicate repeated changes in the surface environments during the Middle and Late Holocene. Episodes of cooling and probable displacement of the Arctic Front to the southwestern part of the Lofoten Basin were recorded for 5–7, 1.6–2.1, and 0.1–1.0 cal. ka BP.
NEW DATA ON THE COMPOSITION OF BASALTS FROM SEAMOUNT NEAR THE EASTERN FLANK OF THE CHARLIE GIBBS FZ (NORTH ATLANTIC)
Authors: Skolotnev S. G. , Peyve A. A. , Dokashenko S. A. , Dobrolyubov V. N. , Okina O. I. , Ermolaev B. V.
Published: April 2024

Composition of basalts collected from the slopes of a single seamount (guyot) located south of the eastern flank of the Charlie Gibbs FZ in the North Atlantic, was studied. High-titanium and low-titanium groups related respectively to E-MORB and T-MORB oceanic tholeites, were singled out. Basalts of the first group are characterized by higher concentrations of TiO2, Na2O, K2O, P2O5, Fe2O3 and incoherent trace-elements. Basalts of both groups were melted from a mantle substrate of similar composition, which is a mixture of DM and HIMU mantle material and to a lesser extent – EM-2. Their difference in composition is due to the fact that high-titanic melts were formed deeper at a level between the spinel and garnet facies. Basalts similar in petro-geochemical and isotopic parameters were found in the axial zone of the Mid-Atlantic Ridge between the Charlie Gibbs and Maxwell FZ, where they compose large neovolcanic edifices formed with a sharp increase in the intensity of axial magmatism as a result of microplumes rise. Our studies give grounds to believe that the studied seamount was also formed as a large neovolcanic structure 64–67 million years ago under the influence of a microplume, which was branch of the Milne plume of the deep mantle.
MORPHOLOGY OF BIOAEROSOL PARTICLES IN THE SURFACE LAYER OF THE ATMOSPHERE OF MOSCOW METROPOLIS
Authors: Gubanova D. P. , Sadovskaya N. V. , Vinogradova А. А. , Iordanskii M. A.
Published: April 2024

Morphological properties of biogenic particles in the near-surface aerosol composition were studied by scanning electron microscopy in Moscow. We analyze the results of complex experiment conducted in 2019–2022 at the IAP RAS to study the variability of aerosol physico-chemical properties in a large city under various weather conditions. The main types of bioaerosol particles were determined, as well as their shape and size. For the first time, brochosomes were detected in the surface aerosol in Moscow during field aerosol observations.
SYMMETRIES OF THE LUNDGREN–MONIN–NOVIKOV EQUATION FOR PROBABILITY OF THE VORTICITY FIELD DISTRIBUTION
Authors: Grebenev V. N. , Grishkov A. N. , Oberlack M.
Published: April 2024

A.M. Polyakov suggested the programme to expand the symmetries admitted by hydrodynamic models to the conformal invariance of statistics in the inverse cascade where the conformal group is infinite-dimensional. In the present work, the group of transformations G of the \(n\)-point probability density function fn (PDF) is presented for the infinite chain of Lundgren–Monin–Novikov equations (the statistical form of the Euler equations) for vorticity fields of the two-dimensional inviscid flow. The problem is written in the Lagrangian setting. The main result is that the group G transforms conformally the zero-vorticity characteristics and invariantly a family of the fn-equations for PDF along these lines. The equations are not invariant along other characteristics. Moreover, the action of G conserves the class of PDF. The results obtained can be used for studying the invariance of statistical properties of the optical turbulence.
MICROWAVE DISCHARGE MAINTAINING IN THE HOLLOW CORE OPTICAL FIBERS FOR GAS FIBER LASERS
Authors: Bufetov I. A. , Gladyshev A. V. , Nefedov S. M. , Kosolapov A. F. , Velmiskin V. V. , Goncharov P. A. , Mineev A. P.
Published: April 2024

The minimal values of the electric 2.45 GHz microwave field, which are necessary to maintain a discharge in a number of noble gases (argon, neon, and helium) in optical fibers with hollow cores of small diameter up to 100 μm, have been measured for the first time. The minimal electric field values for all three gases are (2.5–2.8) kV/cm at a pressure of argon ~50 Torr, neon ~300 Torr, and helium ~500 Torr.
TRANSITION OF SUPERSONIC BOUNDARY LAYER OVER AN UPSWEPT WING DUE TO ACOUSTIC NOISE
Authors: Chuvakhov P. V. , Egorov I. V.
Published: April 2024

Results of direct numerical simulation of the receptivity of the supersonic boundary layer over an upswept wing with a thin parabolic profile to acoustic noise of various intensity are presented. Acoustic noise is shown to be capable of triggering laminar-turbulent transition over the upswept wing of supersonic transport.
MOMENT-MEMBRANE THEORY OF ELASTIC FLEXIBLE PLATES AS A CONTINUAL GEOMETRICALLY NONLINEAR THEORY OF A GRAPHENE SHEET
Authors: Sargsyan S. H.
Published: April 2024

In the present work, under the assumption of smallness of deformations, bending-torsional characteristics and angles of rotation (including the angles of free rotation) of the elements of the plate, based on the three-dimensional geometrically-nonlinear moment theory of elasticity, preserving only those nonlinear terms, that come from normal displacement (deflection) and its derivatives, a geometrically nonlinear moment-membrane theory of elastic plates is constructed as a continual theory of deformations of a flexible graphene. For the indicated nonlinear theory of elastic plates, by introducing stress functions, the resolving equations are presented also in a mixed form: these are the system of equilibrium equations for transverse-bending deformation, compiled in the deformed state of the plate, and deformations continuity equations, expressed in stress functions and deflection functions. For the geometrically nonlinear moment-membrane theory of elastic plates Lagrange-type variational principle is established.
NONLINEAR PHENOMENA DURING THE PROPAGATION OF POWERFUL NANOSECOND ELECTROMAGNETIC PULSES IN A LARGE-SCALE STRIPE LINES WITH A GAS AT REDUCED PRESSURE
Authors: Korobkov S. V. , Gushchin M. E. , Strikovskiy A. V. , Vershinin I. M. , Zudin I. Yu. , Loskutov K. N. , Nikolenko A. S. , Palitsin A. V. , Gromov A. V. , Goykhman M. B. , Mareev E. A.
Published: April 2024

Experiments of propagation of the high-power high-voltage nanosecond and subnanosecond pulses in large-scale transmitting lines in various gases make it possible to solve a wide range of fundamental and applied problems, from simulating the propagation of electromagnetic pulses (EMP) through the atmosphere to estimating the electrical strength of elements of pulsed high-voltage gas-filled systems. At the IAP RAS, experiments with stripe lines up to 5 m in length are performed in Krot and Sprite devices. During the propagation of EMP with an electric field strength up to 100 kV/m in a low pressure gas, the effects are observed such as the formation of non-uniform and essentially non-stationary glow, nonlinear absorption and dispersion transformation of the shape of high-power pulses, due to gas ionization in the EMP field.
DEFORMATION OF A TWO-DIMENSIONAL TRACE PATTERN OF A DETONATION FLOW WITH A “CONTINUOUS” CHANGE IN THE WIDTH OF A FLAT CHANNEL
Authors: Kuzovlev D. I. , Markov V. V.
Published: April 2024

A numerical study of two-dimensional cellular detonation of a hydrogen-air mixture in channels of various widths was carried out and data were obtained on the process of formation of a cellular structure, on the number, shape, and size of cells depending on the channel width. Based on the results of calculations, a classification of two-dimensional cellular detonation structures was carried out. The study was carried out at the facilities of the JSCC RAS. The flow model of a multicomponent reacting mixture was implemented using a customized opensource solver of the OpenFoam framework based on the Kurganov–Tadmor scheme.
NONLINEAR FORCED OSCILLATIONS OF A BUBBLE IN A LIQUID
Authors: Petrov A. G.
Published: April 2024

Forced nonlinear oscillations of a gas bubble in a liquid are investigated when the frequency of fluctuations in the external pressure of the liquid is equal to the natural frequency of the bubble (resonance). By the method of averaging, a simple formula is derived for the dependence of the oscillation amplitude of a gas bubble on the amplitude of the external pressure and the thermophysical characteristics of the gas and the viscosity of the liquid. Its good agreement with numerical calculations is shown up to the value of the oscillation amplitude of the bubble radius comparable to its equilibrium value.
EFFECTIVE METHODS OF SYNTHESIS AND OPTIMIZATION OF A HOLOGRAPHIC MASK
Authors: Chernik V. V.
Published: April 2024

The paper presents several statements of the problems of synthesis of holographic mask in the form of optimization problems for quality of holographic images. An effective algorithm for the synthesis of holographic masks based on FFT with complexity O(NlnN), where N is the number of elements of the depicted object, is described. Based on this algorithm, a scalable software package has been developed and implemented that allows synthesizing holographic masks for various lithography applications, including the production of MEMS, MOEMS and high-end chips. Experimental results are presented.
TRANSFORMATIONS OF 5-HYDRAZINYL-1,2,4-TRIAZINES IN THE REACTION WITH 2,5-NORBORNADIENE
Authors: Krinochkin A. P. , Rammohan A. , Kopchuk D. S. , Nikonov I. L. , Starnovskaya E. S. , Sharafieva E. R. , Kovalev I. S. , Zyryanov G. V. , Chupakhin O. N.
Published: April 2024

The interaction between 5-hydrazinyl-substituted 1,2,4-triazines and 2,5-norbornadiene at elevated temperature and pressure (in autoclave) have been studied. The 2-aminopyridines, 5-amino-1,2,4-triazines and 6-unsubstituted pyridines are the products of this reaction. The formation of last two products depends on the substituent at C3 position of the triazine.
N,O-, N,N-, N,S- AND N,N,S-HETEROCYCLES WITH AN EXOCYCLIC AMINOGROUP IN THE SYNTHESIS OF 1,5,3,7-DIAZADIPHOSPHACYCLOOCTANES
Authors: Spiridonova Yu. S. , Litvinov I. A. , Musina E. I. , Karasik A. A.
Published: April 2024

New 1,5,3,7-diazadiphosphacyclooctanes with N,O-, N,N-, N,S- and N,N,S-heterocyclic substituents at nitrogen atoms were synthesized. The influence of amines containing sp2-hybridized nitrogen atom on the ortho-position of the heterocyclic substituent on the result of a Mannich condensation of primary phosphines, paraformaldehyde and primary amines is revealed. The stabilization of intermediate acyclic products – aminomethyl(hydroxymethyl)arylphosphines and bis(aminomethyl)arylphosphines due to amino-imine tautomerism is a reason of the low yield of cyclic diphosphines on the base of above mentioned amines.
BIOCHEMICAL BASIS OF THE ANTIMICROBIAL ACTIVITY OF QUINAZOLINONE DERIVATIVES IN THE LIGHT OF INSIGHTS INTO THE FEATURES OF THE CHEMICAL STRUCTURE AND WAYS OF BINDING TO TARGET MOLECULES. A REVIEW
Authors: Samotruyeva M. A. , Starikova A. A. , Bashkina O. A. , Tsibizova A. A. , Borisov A. V. , Merezhkina D. V. , Tyurenkov I. N. , Ozerov A. A.
Published: April 2024

The review characterizes the role of the main targets of antibacterial agents: “efflux pumps”; enzymes (DNA-hyruases as a subclass of topoisomerases, homoserine transacetylase, various classes of sorbitases, aromatics, lipoteichoyl synthase, polyketide synthase, pantothenate synthetase, acetyl-CoA carboxylase, sensory histidine kinase, kinase, cyclooxygenase, etc.); penicillin-binding protein; quorum signaling and adhesin systems in important biochemical processes of pathogen maintenance and virulence manifestation. The possibility of manifestation of antimicrobial effect by the substance upon its binding to the protein molecules responsible for pathogenicity of a microorganism was shown. The role of quinazolinone derivatives exhibiting high reactivity, stability in chemical processes and characterized by a wide spectrum of pharmacological activity including antimicrobial activity with respect to various gram-positive and gram-negative bacteria was determined. It has been shown that changes in the compound structure through the introduction of different substituents modify the degree of hydrophilicity and, as a result, determine a different degree of drug penetration through the cell membrane; the ability to form intermediate complex compounds stabilized by hydrogen bonds and van der Waals and stacking interactions with enzymatic targets as well as receptor-regulator proteins and signaling systems of pathogen cells. The results on prediction of the mechanism of action of the compounds synthesized by the authors of the article by methods of mathematical modeling are presented. The possibility of creating combined structures based on the quinazolinone core with various heterocyclic derivatives as a product with a pronounced antimicrobial activity is assessed. The considered regularities are of practical importance for the specialists in the field of medicinal chemistry, organic synthesis, biotechnology, clinical pharmacology, pharmaceutical chemistry and technology whose efforts are aimed at obtaining a new drug substance.
1,3-DEHYDROADAMANTANE AND ITS DERIVATIVES: A VERSATILE SYNTHETIC PLATFORM FOR PREPARATION OF FUNCTIONAL COMPOUNDS WITH A CAGE STRUCTURE. A REVIEW
Authors: Моkhоv V. М. , Butоv G. М. , Novakov I. А.
Published: April 2024

A promising strategy for the synthesis of a functional compounds with framework structure is using of 1,3‑dehydroadamantane (tetracyclo[3.3.1.1.3,7.0.1,3]decane, 1,3-DHA, bridging [3.3.1]propellane) and its derivatives, which are able to restoration of adamantane structure in their reactions. The review provides information on the methods for the synthesis of 1,3-DHA, spectral characteristics, probable intermediates generated from propellanes, and the advantages of using – low-stage syntheses of hardly available adamantine derivatives, atomic precision, and “green chemistry”. The reactions of 1,3-DHA with a wide range of organic compounds are considered, a comparative assessment of its reactivity with respect to CH-, NH-, OH- and SH-acids, as well as arenes, hydantoins, and heterocyclic compounds is carried out. New chemo- and regioselective methods for the one-step introduction of a 1-adamantyl group into the molecules of various substrates are classified. Particular attention is paid to the reactions of 1,3-DHA with various C–H acids, which make it possible to easily form C–CAd bonds to obtain hard-to-reach adamantane derivatives. The influence of pKa of the substrate on the selectivity of the reactions was shown. Low-step methods for the synthesis of new adamantane derivatives, which have shown high activity as hsEH epoxide hydrolase inhibitors and antitumor agents, are described.
EFFECT OF pH ON MOLECULAR ASSOCIATIONS IN FULVIC ACID SOLUTIONS
Authors: Fedotov G. N. , Shoba S. A. , Gorepekin I. V. , Salimgareeva O. A. , Sukharev A. I. , Gracheva T. A.
Published: April 2024

The effect of alkalinization of fulvic acids (FA) solutions on an increase in their optical density is studied. To explain the observed phenomenon, the investigation of FA particles in solutions with different pH was carried out using scanning electron microscopy (SEM) and scanning tunneling microscopy (STM). It was found that with an increase in pH, there is a noticeable decrease in the size of the observed supramolecular formations from FA from about 200 to 100 nm, and when studying FA samples on STM, it was shown that FA in solutions exist in the form of supramolecular formations several hundred nanometers in size, formed by particles-molecules of FA 10–20 nm. An explanation of the observed phenomenon was proposed based on existing ideas about the supramolecular fractal-cluster organization of humic substances (HS). It consists in the fact that the upper layer of F-clusters disintegrates into particles-molecules of FA with a decrease in their size observed with the help of SEM. At the same time, particles-molecules of FA due to their small size are not visible with the help of SEM, but they are well visualized when using STM.
INFLUENCE OF INTRAMOLECULAR DONOR-ACCEPTOR INTERACTIONS ON RADIOLYSIS OF ORGANIC COMPOUNDS: EFFECTS IN ACETYLACETONE
Authors: Vlasov S. I. , Ponomarev A. V. , Ershov B. G.
Published: April 2024

Using acetylacetone as an example, it was shown that the intramolecular hydrogen bond significantly affects the radiolytic transformations of organic compounds, suppressing the transfer of a proton from the primary radical cation to the molecule, and also contributing to the cleavage of the C–OH bond in the enol form. Due to these effects, the main heavy product of radiolysis at 295 K is 4-oxopent-2-en-2-yl acetate. Under boiling conditions (413 K), hydrogen bonds are eliminated, leading to the predominant formation of 4-hydroxy-2-pentanone, which is not detected at 295 K.