bluuebunny/crossref_metadata_2025 huggingface dataset:
NON-SELECTIVE EXPRESSION OF SHORT-WAVELENGTH CONE OPSIN IMPROVES LEARNING IN MICE WITH RETINAL DEGENERATION IN A VISUALLY GUIDED TASK
Authors: Idzhilova O. S. , Kolotova D. E. , Smirnova G. R. , Abonakour A. , Dolgikh D. A. , Petrovskaya L. E. , Kirpichnikov Academician Of the RAS M. P. , Ostrovsky Academician Of the RAS M. A. , Malyshev A. Yu.
Published: April 2024

Here, we explore the potential of an animal opsin non-selectively expressed in various neuronal elements of the degenerative retina to restore impaired visual function. In this study, a knockout murine model of inherited retinal distrophy was used. Animals were injected intravitreally with either a virus carrying gene of the short-wavelength cone opsin associated with a reporter fluorescent protein, or a control virus carrying the sequence of a modified fluorescent protein that had an enhanced membrane tropism. The viral transduction induced pronounced opsin expression in ganglion, bipolar, and horizontal retinal neurons. Behavioral testing of the treated mice in the visually guided task in the trapezoid Morris water maze showed a partial recovery of learning ability in animals whose retinas had been transduced with the cone opsin.
IN HIV-INFECTED IMMUNOLOGICAL NON-RESPONDERS, HEPATITIS C VIRUS ERADICATION CONTRIBUTES TO INCOMPLETE NORMALIZATION OF SYSTEMIC INFLAMMATION INDEXES, BUT DOES NOT LEAD TO RAPID CD4+ T-CELL COUNT RECOVERY
Authors: Saidakova E. V. , Korolevskaya L. B. , Shmagel N. G. , Vlasova V. V. , Shardina K. Yu. , Chereshnev V. A. , Shmagel K. V.
Published: April 2024

In HIV-positive individuals taking antiretroviral therapy, coinfection with hepatitis C virus (HCV) increases the systemic inflammation, which interferes with the CD4+ T-cells regeneration. This study evaluated the effect of HCV eradication on systemic inflammation and CD4+ T-cell regeneration in patients who gave poor response to antiretroviral therapy, the so-called “immunological non-responders” (INRs). HIV-infected patients who received a course of direct-acting antiviral drugs for treating hepatitis C were examined. The control groups included HIV/HCV-coinfected individuals and relatively healthy volunteers. It has been established for the first time that HCV eradication is not accompanied by a complete suppression of systemic inflammation, but improves the T-cell pool composition: in INRs, the blood CD4+/CD8+ T-lymphocyte ratio increases and approaches those of healthy individuals. Apparently, in INRs treated for hepatitis C, the immune system recovery takes time and may be incomplete.
SERUM MIR-181А AND MIR-25 LEVELS IN PATIENTS WITH BREAST CANCEROR A BENIGN BREAST DISEASE
Authors: Autenshlyus A. I. , Perepechaeva M. L. , Studenikina А. А. , Grishanova А. Y. , Lyakhovich V. V.
Published: April 2024

Circulating miR-181а and miR-25, which reflect regulation of the expression of carcinogenesis-related genes, were assayed in patients with invasive carcinoma of no specific type (ICNT) or benign diseases of the breast (BDBs) and in people without pathologies of the mammary gland (controls). MiR-181а expression level proved to be higher compared to control in patients with fibroadenoma and adenosis with low but not high risk of malignant transformation as well as in patients with luminal HER2-negative type B (Lum B HER2–), HER2-positive type (HER2+) and triple-negative breast cancer (TNBC) than in the controls and luminal-type (Lum A) breast cancer. MiR-25 expression level prevailed in patients with Lum B HER2- compared to control, Lum A and TNBC; in patients with TNBC compared to Lum A. Thus, MiR-181а and miR-25 expression levels may be risk indicators of malignant transformation in some patients with BDBs, whereas in patients with ICNT, these levels reflect pathological processes of different directions within the tumor.
EFFECT OF PEGYLATED GRAPHENE OXIDE NANOPARTICLES ON THE METABOLISM OF JURKAT CELLS
Authors: Timganova V. P. , Vlasova V. V. , Bochkova M. S. , Shardina K. Yu. , Uzhviyuk S. V. , Khramtsov P. V. , Rayev M. B. , Zamorina S. A.
Published: April 2024

The effect of graphene oxide (GO) nanoparticles of 100–200 nm size coated with linear (LP-GO) and branched (BP-GO) polyethylene glycol at concentrations of 5 and 25 μg/mL on the metabolism of Jurkat tumor cells was studied. It was found that LP-GO nanoparticles at a concentration of 25 μg/mL can enhance basal glycolysis of Jurkat T lymphocyte tumor cell line cells, while LP-GO and BP-GO at the same concentration can reduce the indicators of compensatory glycolysis. Despite this, GO nanoparticles coated with linear and branched PEG at a concentration of 5 μg/mL do not have pronounced effects on oxidative phosphorylation and glycolysis of Jurkat cells and could therefore be safe for activated T cells.
PEROXIDASE-LIKE ACTIVITY OF MAGNETIC NANOPARTICLES IN THE PRESENCE OF BLOOD PROTEINS
Authors: Gorobets M. G. , Bychkova A. V. , Abdullina M. I. , Motyakin M. V.
Published: April 2024

The generation of hydroxyl radicals from hydrogen peroxide in aqueous solutions containing magnetic nanoparticles (MNPs), hemoglobin (Hb), immunoglobulin G (IgG), and human serum albumin (HSA) has been determined. The dependence of the rate of formation of the oxidized product of o-phenylenediamine (o-PDA) on the concentration of MNPs in solution, as well as on the concentration of proteins, was obtained. The peroxidase-like activity of MNPs was shown to decrease in the presence of HSA and IgG, while the addition of Hb to the reaction mixture was leading to its decrease and increase depending on protein concentration. The obtained effects can be used in the development of systems based on MNPs for theranostics, in particular, for suppression of tumor growth, and in predicting the ability of particles to catalyze the generation of reactive oxygen species (ROS) in vivo.
SIMULATED MICROGRAVITY CHANGES THE NUMBER OF MECHANICALLY GATED AND MECHANOSENSITIVE ION CHANNELS GENES TRANSCRIPTS IN RAT VENTRICULAR CARDIOMYOCYTES
Authors: Kamkin Andre G. , Mitrokhin Vadim M. , Kamkina Olga V. , Kazansky Viktor E. , Rodina Anastasia S. , Zolotareva Alexandra D. , Zolotarev Valentin I. , Sutyagin Pavel V. , Mladenov Mitko I. , Shenkman Boris S. , Kalashnikov Vitaliy E. , Orlov Oleg I.
Published: April 2024

The mechanoelectrical feedback in the heart is based on the work of mechanically gated (MGCs) and mechanosensitive (MSCs) channels. Since microgravity alters the heart’s morphological and physiological properties, we hypothesized that the expression of both MGCs and MSCs would be affected. We employed RNA transcriptome sequencing to investigate changes in the gene transcript levels of MGCs and MSCs in isolated rat ventricular cardiomyocytes under control conditions and in a simulated microgravity environment. For the first time, our findings demonstrated that simulated microgravity induces alterations in the gene transcript levels of specific MGCs, such as TRPM7, TRPV2, TRPP1, TRPP2, Piezo1, TMEM63A, TMEM36B, and known MSCs, including K2P2.1, K2P3.1, Kir6.1, Kir6.2, NaV1.5, CaV1.2, KV7.1. However, other voltage-gated channels and channels lacking a voltage sensor remained unaffected. These findings suggest that the altered expression of MGCs and MSCs could lead to changes in the net currents across the membrane, ultimately impacting the heart’s function.
CHROMATIN REMODELING COMPLEX PBAF ACTIVATES AND REPRESSES INFLAMMATORY GENES
Authors: Feoktistov A. V. , Georgieva S. G. , Soshnikova N. V.
Published: April 2024

The PBAF chromatin remodeling complex regulates chromatin state and gene transcription in higher eukaryotes. In this work, we studied the role of PBAF in the regulation of NF–κB-and JAK/STAT-dependent activation of inflammatory genes. We performed knockdown of specific module subunit BAF200 resulted in destruction of the entire PBAF specific module and changed the level of the genes transcription of both pathways. PBAF can be both an activator and a repressor of inflammatory genes. Thus, PBAF is one of the important regulators of inflammatory gene expression.
CBP AND RAD21 BIND AT THE TERMINI OF FORUM DOMAINS IN HUMAN CHROMOSOMES
Authors: Tchurikov N. A. , Alembekov I. R. , Klushevskaya E. S. , Meilakh P. B. , Kretova A. N. , Managrova O. D. , Kravatskaya G. I. , Kravatsky Y. V.
Published: April 2024

Forum-domains are 50–100-kb stretches of DNA delimited by the hot sport of DSBs. These domains possess coordinately expressed genes. However, molecular mechanisms of such regulation are not clear. It is supposed that the proteins specifically binding at the termini of domains could be involved in coordinated regulation of expression. In this study we used the results of precise mapping of hot spots of DSBs and ChIP-Seq data for ten nuclear proteins in HEK293T cell line for a search of proteins specifically binding at forum-domains termini. We detected that two proteins – CBP and RAD24-, which are known to be involved in epigenetic regulation of gene expression and formation of 3D chromosomal structures, bind at the termini. We suppose that these proteins could be involved in coordinated expression of genes in forum-domains.
INVESTIGATION OF THE INTRACELLULAR DISTRIBUTION OF DOXORUBICIN IN MCF-7 HUMAN BREAST ADENOCARCINOMA CELLS BY THE METHOD OF CORRELATIVE SCANNING FLUORESCENT PROBE NANOTOMOGRAPHY
Authors: Agapova O. I. , Efimov A. E. , Mochalov K. E. , Solovyeva D. O. , Gileva A. M. , Markvicheva E. A. , Yakovlev D. V. , Lyundup A. V. , Oleinikov V. A. , Agapov I. I. , Gautier S. V.
Published: April 2024

The development of technologies for effective targeted drug delivery for oncotherapy requires the elaboration of new methods to analyze the features of micro- and nanoscale distributions of antitumor drugs in cells and tissues. This paper presents a new approach to three-dimensional analysis of intracellular distribution of cytostatics using fluorescence scanning optical-probe nanotomography technology. Correlative analysis of nanostructure and distribution of injected doxorubicin in studied MCF-7 human breast adenocarcinoma cells made it possible to reveal the features of drug penetration and accumulation in cells. The developed technology based on the principles of scanning optical probe nanotomography is applicable to study the distribution patterns of various fluorescent or fluorescence-labelled substances in cells and tissues.
HYDROCARBONS IN THE SURFACE MICROLAYER AND ICE OF THE KARA SEA
Authors: Nemirovskaya I. A. , Khramtsova A. V.
Published: April 2024

Concentrations and composition of hydrocarbons – HCs (aliphatic – AHCs and polycyclic aromatic hydrocarbons – PAHs) in the Kara Sea (cruise 83 of the R/V Academic Mstislav Keldysh, June 2021) in the sea surface microlayer – SML (about 300 µm thick), ice and surface waters weree defined. The concentration of AHCs in SML occurs in suspended particulate matter (SPM), where their content varied in the range of 197–1051 µg/l, on average 621 and was almost 4 times higher than in the dissolved form: 89–270, on average 158 µg/l, and according to compared with the suspended form of surface waters – almost 22 times higher (on average 33 µg/l). The accumulation of organic compounds also occurs in ice, but to a lesser extent than in the SML. According to the composition of alkanes, the influence of autochthonous processes on the formation of AHCs in surface microlayer and melting ice is mostly insignificant, and this distinguishes their behavior from the ice that forms. The content of PAHs in surface microlayer in SPM was also 4.8 times higher on average than in the dissolved form. Despite the different sources of these hydrocarbon classes, for all samples taken, a dependence was observed in the distribution of AHCs and PAHs in SPM (r = 0.79, n = 52, at p 0.01). In the composition of PAHs, according to the markers, the influence of combustion products of marine fuel is traced, since, in addition to phenanthrene, fluoranthene and pyrene dominated in all samples.
MULTI-YEAR SUCCESSION OF BIOFOULING COMMUNITIES ON UNDERWATER ARTIFICIAL STRUCTURES IN THE APHOTIC ZONE OF THE SEA OF OKHOTSK
Authors: Chava A. I. , Mokievsky V. M.
Published: April 2024

А 10-year succession of the fouling community inhabiting underwater manmade structures at a depth of 80–90 m was described using the materials from regular video surveys of the technical installations on the southwestern shelf of the Sea of Okhotsk. A general scheme of macrofouling community developmental stages in steps of 1–2 years has been compiled both for the intact community and for sites subjected to the single or multiple hydrodynamic cleaning. For each stage we visually estimated the projective cover of macrofouling and identified the characteristic dominant species down to the smallest possible taxon. The first two years of the intact community are characterized by low projective cover (up to 50%), in the third year and further there is a sharp increase in the abundance and diversity of macrofouling organisms. Barnacles Chirona evermanni, sponges Phakellia sp., bryozoans Securiflustra securifrons, and ascidians Boltenia ovifera were noted among the dominant species in the community older than two years. The early stages of restorative succession differ from the intact succession in terms of dominant species and developmental rates.
DIRECT AND INVERSE ENERGY CASCADE IN THE OCEAN DURING VORTEX ELONGATING
Authors: Zhmur V. V. , Belonenko T. V. , Novoselova E. V. , Suetin B. P.
Published: April 2024

When mesoscale vortices interact with the flow, there are three variants of their behavior: rotation, nutational oscillations, and unlimited elongating. This paper describes the physical conditions of vortex transforming into filaments. We estimate the proportion of vortices that are stretching out into filaments in the World Ocean and some regions. Due to the elongation, the vortices redistribute the energy from mesoscale to submesoscale.
ORE MINERALIZATION OF THE OZHEREL’E DEPOSIT: COMPARISON WITH OBJECTS OF THE “SUKHOI LOG” TYPE
Authors: Budyak A. E. , Tarasova Yu. I. , Goryachev N. A. , Blinov A. V. , Ignatiev A. V. , Velivetskaya T. A. , Abramova V. D. , Shcherbakov D. Yu.
Published: April 2024

Within the Lena gold province, in addition to the well-known large-volume gold deposits of the “Sukhoi Log” type, such as Sukhoi Log, Verninskoye, etc. there are a number of objects that differ significantly in stratigraphic, mineralogical-petrographic, isotopic, geochemical characteristics and the volume of reserves. The most famous of them is the Necklace deposit. The article shows the main characteristics of the Ozherel’e deposit, highlighting its similar and distinctive features with deposits of the “Sukhoi Log” type. The results obtained in the course of mineralogical-petrographic and isotope studies do not give grounds for attributing the Necklace deposit to the “Sukhoi Log” genetic type.
THE FIRST INFORMATION ABOUT THE GOLD-COPPER MINERALIZATION OF THE KONTORSKOYE ORE OPENING (ARIADNE INTRUSION OF ULTRABASITES, PRIMORYE)
Authors: Khanchuk A. I. , Molchanov V. P. , Androsov D. V.
Published: April 2024

Within the Sikhote-Alin orogenic belt, a new promising type of mineral resources has been identified – complex ores and placers spatially and genetically related to Late Mesozoic ultramafic intrusions. An example of this is the Ariadne massif of ultramafic rocks, in the center of which there is a manifestation of gold-titanium mineralization, and in the exocontact – gold-antimony. The main features of the mineralogy and geochemistry of gold-copper formations in its near-intrusive zone are determined. To reconstruct the conditions for the formation of these ores, the isotopic composition of sulfur in sulfide minerals was studied. The obtained materials testify to the significant metal-bearing potential of the ultramafic rocks of the Sikhote-Alin.
EXPERIMENTAL TESTING OF THE METHOD OF ACOUSTIC THERMOMETRY ON A LONG TRACK IN THE SEA OF JAPAN
Authors: Dolgikh G. I. , Morgunov Yu. N. , Bezotvetnykh V. V. , Burenin A. V. , Golov A. A. , Voitenko E. A. , Razzhivin V. V. , Tagiltsev A. A.
Published: April 2024

The methodological and technical possibilities of monitoring temperature fields on a thousand-kilometer track in the Sea of Japan using acoustic thermometry methods are presented. The proposed tomographic method for monitoring the dynamics and structure of water is based on the emission and reception of complex phase-shift keyed signals on a diagnosed path with the determination of the propagation time along various ray trajectories, followed by the calculation of the speed of sound and temperature. The physical prerequisites for the practical implementation of thermometric studies at large distances are based on the effect of an acoustic “mudslide” – the phenomenon of the transition of acoustic energy from the near-bottom shelf area to the underwater sound channel of the deep ocean. In the example of the Sea of Japan, a high-precision acoustic thermometry system based on tomographic schemes with mobile and stationary hydroacoustic emitters and receiving systems was proposed and experimentally tested.
HYPOTHESIS ON THE REASONS FOR STRONG VARIABILITY CONCENTRATIONS OF IMPURITIES IN NATURAL WATERS
Authors: Danilov-Danilyan V. I. , Rozenthal O. M.
Published: April 2024

A hypothesis has been put forward about the formation of an increased dispersion of the concentration of substances polluting the water of the river flow under the influence of internal synergistic factors. The effect is manifested in the dispersion of controlled quality indicators, exceeding their average value, which in practice makes it difficult to manage water use. An assumption is made that such a dispersion is a consequence of the nonlinearity of systems that are far from thermodynamic equilibrium. It is possible that the driving force in this case is the turbophoresis of impurity particles in a turbulent, as a rule, water flow.
SOURCES OF THE LATE CENOZOIC DEPOSITS FROM THE AEOLIAN “SANDS” MASSIF IN THE CHARA BASIN OF THE BAIKAL RIFT ZONE: FIRST RESULTS OF U–TH–PB (LA-ICP-MS) GEOCHRONOLOGICAL STUDY OF DETRITAL ZIRCON
Authors: Buchnev I. N. , Adamskaya E. V. , Bobrovskaya O. V. , Skovitina T. M. , Kotov A. B. , Lopatin D. V. , Kovach V. P.
Published: April 2024

The results of U–Th–Pb (LA-ICP-MS) geochronological studies of detrital zircon (fraction more than 50 µm) from the Late Cenozoic deposits of the large aeolian “Sands” massif of the Chara Basin of the eastern flank of the Baikal Rift Zone show that they are dominated by detrital zircon with ages of 263–265 and 1861–1864 Ma. Archean ages have been obtained only for individual zircon grains. Quite possibly, this is due to the fact that zircon of this age is present in “small” fractions, the study of which is not possible due to the technological features of the method of geochronological studies used. Based on the geological situation, only granites of the Kodar complex can be considered as the only source of detrital zircon of the Early Proterozoic age. The source of detrital zircon with an age of 263–265 Ma remains a mystery. Granitoids of this age are not known on the territory of the Aldan Shield. They are widespread in its western frame.
TECTONIC SCHEME FOR THE AMERASIA BASIN OF THE ARCTIC OCEAN
Authors: Chernykh А. А. , Yakovenko I. V. , Kaminskiy V. D. , Glebovskiy V. Yu. , Korneva M. S. , Bashev I. A.
Published: April 2024

The tectonic scheme of the Amerasia Basin, as a result of a comprehensive analysis of geological and geophysical data, was created for the first time at 1:2 500 000 scale. The structural framework of the scheme was developed based on the results of basement mapping using reflection seismic sections and its detailing according to potential fields. The results of three-dimensional gravity modeling, presented by Moho depth and consolidated crust thickness calculations were used as basic indicators of the genesis of the crust. Tectonic elements of different ranks and kinematics were identified on seismic sections and traced according to potential fields. The created scheme is the most detailed among the published earlier, it demonstrates the features of the tectonic structure of individual geostructures, their nature and allows us to draw conclusions about the evolution of the Amerasia Basin. The listed issues are discussed in the text of the article.
FORMATION CONDITIONS OF THE DEVONIAN BASITES OF THE VILYUI-MARKHA DIKE SWARM OF THE VILYUI PALEORIFFT (SIBERIAN PLATFORM)
Authors: Simonov V. A. , Polyansky O. P. , Kotlyarov A. V. , Karmanov N. S. , Koroleva O. V. , Prokopiev A. V.
Published: April 2024

Melt inclusions in the minerals of a sample from a dolerite dike of the Vilyui-Markha dike swarm, located on the northwestern shoulder of the Vilyui paleorift, have been studied. Data on the composition of homogeneous glasses of melt inclusions in minerals made it possible to establish the PT-parameters of mantle sources of initial deep melts responsible for the formation of gabbro-dolerites of the Vilyui paleorift. Two levels of generation of initial melts for dolerites have been established: in the intervals of 95–65 km at 1480–1400°C and 55–45 km at 1360–1320°C. The presence of two intermediate chambers in the crust, where melts crystallized, was identified at depths of about 12 and 9–4 km with a decrease in temperature to 1175–1125°С. The two-level arrangement of magma generation centers, as well as the heterogeneity of the chemical composition of the studied minerals, makes it possible to explain the presence of two pulses of Devonian basic magmatism.
PEAT DEPOSITS AS A NEW SOURCE OF PALEOMAGNETIC RECORDS IN THE HOLOCENE AS EXEMPLIFIED BY THE ETRUSSIA EXCURSION
Authors: Peskov A. Yu. , Didenko A. N. , Karetnikov A. S. , Klimin M. A. , Arkhipov M. V. , Kozhemyako N. V. , Tikhomirova A. I.
Published: April 2024

The paper presents the results of microprobe, paleomagnetic and rock magnetic studies on peats from the Tyapka peat section (Khabarovsk region) formed 4 thousand years. Alternating field demagnetization of peats yielded a horizon of 57–109 cm (1833–3083 cal. BP) with negative inclination values of the magnetization vector, which corresponds to the geomagnetic Etrussia excursion. Obtaining relative paleointensity estimates for peats was pioneered, which are consistent with the literature archeomagnetic data for the western part of Eurasia. It was found that the Etrussia excursion took place against the background of increased values of the Earth’s magnetic field, and its duration was ~ 1200 years.
NEW EVIDENCE OF THE INDEPENDENT PRECAMBRIAN TECTONIC HISTORY OF THE FADDEY TERRANE OF THE CENTRAL TAIMYR ACCRETIONARY BELT
Authors: Matushkin N. Yu. , Metelkin D. V. , Vernikovsky V. A. , Proskurnin V. F. , Abashev V. V. , Larionov A. N. , Petrushkov B. S.
Published: April 2024

New geostructural, petro-geochemical, U-Pb geochronological and paleomagnetic data for sills of metagabbro-dolerites of the Severnobyrranga and Yasnenskiy complex specify the paleotectonic position of the Faddey terrane of the Central Taimyr accretionary belt. The structural position of the sills in the rocks of the Oktyabr and Zhdanov formations is indicative of their intrusion before deformations caused by the accretion of the Central Taimyr belt. The U-Th-Pb age of crystallization for the metagabbro-dolerites has been established as 1357 ± 9 Ma. The primary paleomagnetic record reflecting the time of intrusion has not been preserved, but two metachronous components have been identified. The first one corresponds to crust formation processes at ca. 840 Ma due to collision, probably of continent – island arc type involving the cratonic block that included the Faddey and Mamont-Shrenk terranes. These collisional events took place several hundreds of kilometers from the Siberian margin. The second component corresponds to thermal events on the Paleozoic-Mesozoic boundary and reflects the strike-slip deformation in the Kara orogen.
NEOPROTEROZOIC DIAMICTITES OF THE MIDDLE TIANSHAN, KYRGYZSTAN: AGE, DEPOSITIONAL ENVIRONMENTS AND PROVENANCE
Authors: Alexeiev D. V. , Khudoley A. K. , DuFrane S. A. , Kushnareva A. V. , Bryanskiy N. V. , Karimov A. A.
Published: April 2024

With the aim to improve our understanding of the age and genesis of the Neoproterozoic diamictites of the Middle Tianshan of Kyrgyzstan, we studied the late Precambrian strata of the Sandalash, Talas and Chatkal Ranges. The results of detrital zircon dating indicate that diamictites were deposited in the Cryogenian and Ediacaran. Diamictites in the lower part of the Shorashu Formation comprise tillites and were likely deposited during the Marino glaciation ca 640–635 Ma. Diamictites in the upper part of the Shorashu Formation represent debris flows and grain flows associated with turbidites and, apparently, have non-glacial origin; their age is not older than the early Ediacaran 616 ± 7 Ma. The pinching out of the Shorashu Formation to the north and the predominantly southerly directions of sediment transport in turbidites indicate that a non-depositional uplift located north of the basin. The distributions of detrital zircon ages in the studied samples are characterized by large peaks at 0.7–0.8 and 1.8–1.9 Ga and small peaks at ca 2.4–2.5 Ga and are almost identical to the age distributions in the Proterozoic sediments of the Tarim Craton. Comparison of the studied strata with key sections of the Kuruktag Range in the NE Tarim suggests that the diamictites of the lower part of the Shorashu Formation are analogues of late Cryogenian Tereeken tillites, and the slope facies of the upper part of the section are analogues of the early Ediacaran turbidites of the Zhamokti and Yukkengol Formations.
SOURCES OF SUBSTANCE AND GENETIC RELATION OF SOIL AND BAUXITE BEARING HORIZONS IN THE LATERITE PROFILE OF THE WEATHERING CRUST (OF THE FUTA JALLON-MANDINGO PROVINCE, REPUBLIC OF GUINEA)
Authors: Makarova M. A. , Shipilova E. S. , Boeva N. M. , Vnuchkov D. A. , Bortnikov N. S.
Published: April 2024

For the first time, a granulometric analysis of lateritic soils was carried out and the sources of the substance involved in the formation of the degradation zone in the bauxite-bearing laterite profile of the bauxite-bearing province of Futa Jallon-Mandingo were identified. Throughout the province, on the stony rocks of the lateritic covers, the soil horizon occurs everywhere - the uppermost element of the vertical profile of the weathering crust. In the soil horizon, most of the components become mobile, leaching processes predominate, and laterites are mobilized and redistributed. The study of these continental formations made it possible to establish the genetic relationship between the soil horizon of the weathering crust and the underlying bauxite ores, and to determine the degree of influence of soil composition on the processes of bauxite formation.
SORPTION OF RARE-EARTH ELEMENTS BY ORGANIC MATTER FROM AQUEOUS SOLUTIONS ACCORDING TO EXPERIMENTAL DATA
Authors: Pavlova L. M. , Shumilova L. P. , Radomskaya V. I. , Sorokin A. P. , Ivanov V. V. , Noskova L. P. , Leusova N. Yu.
Published: April 2024

Laboratory model experiments have shown that peat, brown coal and its constituent organomineral components, as well as microscopic fungi isolated from brown coal, are characterized by a high potential for the extraction of all lanthanides from aqueous solutions. The processes of sorption of rare-earth elements by the components of organic matter proceed through the mechanisms of physical sorption, ion-exchange reactions involving carboxyl and hydroxyl groups, and complex formation involving –OH, –CO, and –COOH groups. SEM-EDS analysis revealed REE-containing mineral phases on fungal biomass, which are formed due to interaction with phosphorus- and nitrogen-containing functional groups of cell wall proteins. This indicates the participation of the biotic component in the formation of rare earth mineralization in brown coal deposits.
Sr-ISOTOPIC COMPOSITION OF PALEOOCEAN WATER ON THE BORDER OF 960 Ma (DATA FOR NIZHNY TUNGUSKA FORMATION OF TURUKHAN UPLIFT OF SIBERIAN PLATFORM)
Authors: Letnikova E. F. , Zhdanov A. A. , Ivanov A. V. , Maslov A. V. , Izokh A. E. , Letnikova A. F. , Soloshenko N. G.
Published: April 2024

At the boundary of the Meso- and Neoproterozoic, Grenville collision events were widely manifested on the margins of ancient continental blocks. Most of the sedimentary sequences that had accumulated by that time had undergone significant thermal–metamorphic changes. In many ways, this is the main reason for the lack of isotopic data for carbonate deposits in the interval of 1200–900 Ma in world practice. Sr–isotopic composition in carbonate rocks with an age of 980–920 Ma was determined in the only section of the World – the Huainan Formation of the North China Platform with accumulation time determined by U–Pb dating of detrital zircon grains. In the upper part of the Nizhny Tunguska suite of the Turukhansk uplift, among carbonate deposits, we established the presence of altered volcanic rocks, as well as weathering crust products along them – poor bauxite and chamosite ores. Based on U–Pb zircon isotope dating, the age of the volcanic rocks is 964 Ma. For the least altered limestones of the upper part of the Nizhny Tungusska Formation, received 87Sr/86Sr values are 0.70532–0.70578, which are close enough to those found in the rocks of the Huainan Formation. Geochronological age of the studied limestones gives us more correct data. These data can be used to refine the previously proposed configuration of the Sr–isotopic composition variation curve in the Early Neoproterozoic. The Nizhny Tunguska Formation is the only carbonate section of the Early Neoproterozoic in the world with correctly geochronologically substantiated dating (based on zircon from subsynchronous volcanic rocks). This compares favorably with the Huainan formation.
SOME FEATURES OF THE PROCESS OF INTERACTION OF IRON WITH METHANE AT A TEMPERATURE OF 900°C AND A PRESSURE OF 100 MPA
Authors: Aranovich L. Ya. , Persikov E. S. , Bukhtiyarov P. G. , Shaposhnikova O. Y. , Nekrasov A. N.
Published: April 2024

Using the original high-gas pressure unit (IHPV), experiments were conducted for the first time on the interaction of iron with methane at a temperature of 900°C and a pressure of 100 MPa. Complex methods (microprobe, Raman spectroscopy, chromatography, mass balance calculations) are used for a thorough analysis of fluid compositions and metallic phases formed in experiments. For the first time, experimental and theoretical quantitative data on the composition of the fluid and the composition of the fluid components dissolved in the metal were obtained. Unlike the previously studied Fe3C–H2 system, in experiments, when Fe reacts with methane, there is an active interaction of carbon formed due to the pyrolysis of methane with iron up to the synthesis of Fe3C carbide. The experiments have shown that increasing pressure inhibits significantly hydrogen yield during methane conversion on metallic iron. Carbon saturation of iron with the formation of Fe3C is not complete within the entire volume of the metal during 24 h runs at 900°С. Employing molybdenum containers facilitates CH4 decomposition.
AN UPPER MOLAR OF A DOCODONTAN (DOCODONTA, MAMMALIAFORMES) FROM THE LOWER CRETACEOUS OF WESTERN SIBERIA
Authors: Lopatin A. V. , Averianov A. O. , Ivantsov S. V. , Kuzmin I. T. , Skutschas P. P.
Published: April 2024

According to the degree of development of the main cusps and the presence of a small lingual part, the upper molar of a docodontan from the Bol’shoi Kemchug 4 locality (Ilek Formation, Lower Cretaceous) in the Krasnoyarsk Territory corresponds to M1 of Agilodocodon scansorius Meng et al., 2015 from the Middle Jurassic of China. The described tooth may belong to Sibirotherium rossicum Maschenko et al., 2003 known from more complete remains (without M1) from the Ilek Formation of the Shestakovo 1 locality (Kemerovo Region), which could have four upper molars similar in structure to those of Agilodocodon.
GENETIC FEATURES AND FLOTATION PROPERTIES OF THE PORPHYRY COPPER–GOLD ORE (MALMYZH DEPOSIT, KHABAROVSKY DISTRICT, RUSSIA)
Authors: Rasskazov I. Yu. , Gurman M. A. , Shcherbak L. I.
Published: April 2024

The material composition, structural and textural features of porphyry-copper-gold ore reflect the conditions of ore formation and are of decisive importance for predicting the technological properties of ore and increasing the complexity of the use of mineral raw materials. The sequence of ore formation with three stages identified: greisen, sulfide (productive) and explosive microzones within the studied interval of the ore body is presented. Features of ore and rock-forming minerals that determine their flotation behavior and properties that hinder the selectivity of flotation were revealed. The complex composition of the studied ore was established.
RARE EARTH ELEMENT RESOURCE POTENTIAL OF SUPER-LARGE DEPOSITS IN EASTERN FENNOSCANDIA
Authors: Kogarko L. N.
Published: April 2024

Work has been carried out to assess the rare-earth potential of the main ore minerals -loparite, eudialyte and apatite of the Lovozersky and Khibinsky deposits. Super-large deposits of loparite and eudialyte are associated with the giant Lovozero intrusion (Eastern Fennoscandia, Kola Peninsula). There are a number of apatite deposits in the Khibiny complex. All these ores occupy a leading place in the structure of the raw material of Russia. The highest contents of the sum of rare earth metals are characteristic of loparite ores (the content of ΣREE in loparites is about 28 wt%), and light rare earths sharply prevail over heavy ones, the Ce/Yb ratio is about 78 000. The amount of REE in eudialites is about 2 by mass%. A remarkable feature of eudialyte ores is the high concentrations of the heavy REE group, the Ce/Yb ratio is about 14. The apatites of the Khibiny deposits occupy an intermediate position: the Ce/Yb ratio is 680, and the average concentration of the REE sum is 0.9 wt%. The conditions of formation of apatite, loparite and eudialyte ores are considered.
EVOLUTION OF THE VICTORIA PIPE ULTRAMAFIC ALKALINE MELT (ANABAR REGION, SIBERIAN CRATON): MELT INCLUSION WITHIN OLIVINE AND GROUNDMASS MINERALS
Authors: Kargin A. V. , Prokopyev I. R. , Starikova A. E. , Kamenetsky V. S. , Golubeva Yu. Yu.
Published: April 2024

To provide new insights into evolution of the primary ultramafic alkaline melts, we present an investigation of the primary and secondary melt inclusions within olivine macrocrysts and groundmass minerals from the Victoria monticellite-nepheline damtjernite, Anabar diamondiferous province, Siberia craton. The primary melt inclusions within olivine macrocrysts shown that initial damtjernite melts were K–Na bearing carbonate-silicate melts by composition whereas the K and Na associated within only silicate phases like that phlogopite, nepheline, kalsilite. That distinguishes these inclusions from similar inclusions in olivines from aillikites and kimberlites and emphasizes a more alkaline character of the damtjernitic parental melts. Based on the composition of melt inclusions within spinel and monticellite from magmaclastic groundmass, under the further evolution of the damtjernitic melts, K and Na are not only included in silicate daughter phases, but they can also form alkaline phosphates, carbonates, sulfates, and halides. That led to form the alkaline carbonate and saline sulfate-phosphate-chloride-carbonate liquids. This composition of the evolved ultramafic alkaline melt is common for melt inclusions within different minerals from aillikite, kimberlite and some carbonatites highlighted uniform mechanism of evolution of alkaline-ultramafic melts. Further accumulation of the fluid phase led to its reaction interaction with olivine with the formation of monticellite and degassing processes.
FIRST RESULTS OF COMPLEX DATING AND GROWTH RATE ESTIMATION OF SPELEOTHEM FROM VORONTSOVSKAYA CAVE (KRASNODAR REGION, RUSSIA)
Authors: Gavriyshkin D. A. , Maksimov F. E. , Pasenko A. M. , Veselovskiy R. V.
Published: April 2024

Speleothems are unique archives of information about climate, geomagnetism, and ecological conditions of past epochs of the Earth, and over the past two decades have been successfully used for paleoclimatic and paleomagnetic studies. The uniqueness of these geological objects lies in the peculiarities of their formation and preservation in them of a wide range of geochemical, geological and geophysical proxies, and, most importantly, in the ability to obtain time series of these proxies in an unprecedentedly accurate resolution using 230Th/U, 14C and some other geochronological methods, as well as incremental chronology. This paper presents the first results of dating the Vor speleothem from the Vorontsovskaya Cave (Krasnodar region), which preserved a record of the geomagnetic excursion, obtained by 230Th/U α-spectrometry, 14C dating, and incremental chronology. Such studies have been carried out in Russia for the first time. Despite the limitations of using the methods of isotope geochronology, it was possible to obtain a limit on the age of the excursion, which probably occurred no earlier than 5500–6000 years ago. At the same time, the incremental chronology made it possible to determine with great accuracy the duration of the main phase of the excursion, which equals 871 ± 16 years, during which the virtual geomagnetic pole was in the southern hemisphere, and also to obtain the upper limit on the age of the excursion, which probably occurred no later than 5.5–6 thousand years ago.
CONTENT AND COMPOSITION OF HYDROCARBONS IN WATER AND SEDIMENTS IN COASTAL REGIONS OF THE RUSSIAN SECTOR OF THE BLACK SEA
Authors: Nemirovskaya I. A. , Khramtsova A. V. , Zavialov P. O. , Konovalov B. V.
Published: April 2024

The current level and origin of hydrocarbons (HCs) was determined: aliphatic – AHCs and polycyclic aromatic – PAHs (September 2021, May and September 2022) in suspended particulate of surface waters (for AHCs – 20 µg/l; PAHs – 130 ng/l, fluorescent method) and in the bottom sediments of the coastal areas of the Caucasian sector of the Black Sea of the Russian Federation. Despite the decrease in HC concentrations in surface waters in recent years, the most polluted areas include, as before, the Kerch Strait. HC accumulate in bottom sediments, which leads to an increase in their content in the composition of Corg (up to 14.2% in the Tuapse region and 13.1% in the Novorossiysk region). It has been established that, along with pollution, HC levels are greatly influenced by natural processes (the productivity of the area, fluid flows from the sedimentary mass).
THE NEW POLITYPES STRUCTURES Pd8T3 (T = As, Sb)
Authors: Karimova O. V. , Mezhueva A. A. , Eremin N. N.
Published: April 2024

The polytypic structures of Pd8T3 (T = As, Sb) compounds was revealed using the graph method. The topology of the layers and the pattern in the sequence of their alternation are analyzed. The ordering of antimony and arsenic atoms by positions at the nodes of layer-networks and the positional disorder in the sequence of alternating layers, which lead to the formation of different structural polytypes, are considered.
TRANSFER OF A DROP MATERIAL DURING THE PRIMARY CAVERN FORMATION
Authors: Chashechkin Yu. D. , Ilyinykh A. Yu.
Published: April 2024

The transfer of a freely falling drop matter in the bulk of a target fluid at rest at the stage of primary cavity formation was traced by high-speed video recording for the first time. In the experiments, drops of water, ink solution (diluted in a ratio of 1:100) or a saturated solution of baking soda with a diameter of D = 0.43 cm fell with velocity of U = 3.1 m/s into fresh water or a 20% ammonium thiocyanate solution in the splash formation mode. In all experiments, the wall of the growing cavity was penetrated by thin fibers containing drop matter, which form an intermediate fine-structured layer. After the end of the fiber growth stage with a duration of 7–8 ms, the diffusion smoothed the concentration gradients, a liquid shell of intermediate density with a thickness of 1.5 to 0.7 mm was formed around the growing cavity. The shell is separated by a sharp boundary from the target fluid. A new group of inclined fibrous loops was formed in the wake of the collapsing cavity.
ASSESSMENT OF TEMPERATURE STRESSES IN THE LITHOSPHERE OF THE EARLY MOON
Authors: Voropaev S. А. , Krivenkо А. P.
Published: April 2024

In the early stages of the Moon’s formation, its growing lithosphere experienced complex time-varying temperature and gravitational stresses. Despite the subsequent intense impact transformation of the surface, during the gravimetric study of the GRAIL space mission, the presence of ancient deep intrusions was detected. The analysis of linear gravitational anomalies shows the expansion of the outer rigid layer of the planet at a certain early stage of the Moon’s evolution due to the excess of temperature stresses over gravitational compression. Obtaining the dependence of the time interval of the lithosphere expansion on a number of dimensionless thermal conductivity parameters will make it possible to refine existing models of the thermal and geochemical evolution of the early Moon.
SPECIFIC FEATURES OF PULSED CATHODOLUMINESCENCE UNDER EXCITATION BY NANOSECOND AND SUBNANOSECOND ELECTRON BEAMS
Authors: Yalandin M. I. , Solomonov V. I. , Spirina A. V. , Shunailov S. A. , Sharypov K. A. , Makarova A. S. , Lipchak A. I.
Published: April 2024

Pulsed cathodoluminescence of crystals and ceramics was excited by runaway electron beams with a duration of 10–12 ps and electron beams with a duration of 2 ns generated in a vacuum diode. The results of comparative studies of their pulsed cathodoluminescence parameters are presented. The luminescence spectrum and the decay kinetics of the bands are shown to coincide in both cases. When excited by a beam of runaway electrons, a lower luminescence intensity is observed. Also in some cases a delay in the appearance of luminescence relative to the onset of the electron beam action was found. The mechanism for the delay appearance under excitation by a runaway electron beam is associated with the process of luminescence rise.
STRUCTURE AND PROPERTIES OF A HIGH-ENTROPY AlCrFeCoNi ALLOY AFTER ELECTRON-ION-PLASMA TREATMENT
Authors: Gromov V. E. , Ivanov Yu. F. , Efimov M. O. , Shliarova Yu. A.
Published: April 2024

With the help of wire arc additive manufacturing, a HEA of AlCrFeCoNi was prepared: of a non-equiatomic composition, on which a B + Cr film with a thickness of ~1 μm was deposited by plasma-assisted RF sputtering. Subsequent processing consisted in electron-beam irradiation of the surface with the following parameters: energy density 20–40 J/cm2, pulse duration 200 μs, frequency 0.3 s–1, number of pulses 3. A quasi-periodic distribution of chemical elements (at. %) 33.4Al; 8.3Cr; 17.1 Fe; 5.4Co; 35.7 Ni is established. It is shown that at the energy density of the electron beam Es = 20 J/cm2, the microhardness increases by a factor of 2, wear resistance by a factor of 5, and the friction coefficient decreases by a factor of 1.3. High-speed crystallization of the surface layer leads to the formation of a subgrain structure with subgrain sizes (150–200 nm). The increase in strength and tribological properties during electron-beam processing is interpreted taking into account the reduction in grain size, the formation of chromium and aluminum oxyborides, and the formation of a solid solution of boron incorporation into the HEA crystal lattice.
CARBON-FREE RUSSIA: IS THERE A CHANCE TO ACHIEVE CARBON NEUTRALITY BY 2060?
Authors: Klimenko V. V. , Klimenko A. V. , Tereshin A. G.
Published: April 2024

The prospects for reducing the carbon intensity of the Russian economy and the possibility of achieving climate neutrality of the national economy by 2060 are studied On the basis of a historical-extrapolation approach to the study of the development of various sociotechnical systems by comparing with the dynamics of carbon indicators of the economies of the leading countries of the world, it is shown that full compensation for anthropogenic emissions of greenhouse gases (GHGs) by absorption by the biosphere (primarily forests) is theoretically possible with implementation of difficult-to-implement large-scale reform programs in all sectors of the country’s economy – from energy to forestry. Thus, in an optimistic scenario, the rate of decline in specific GHG emissions per capita should be the maximum value achieved in the world over the past 50 years at 1% per year, and forest management should include full compensation for growing deforestation and a 50% reduction in forest losses from fires, which are currently the second (after energy) sources of GHG emissions into the atmosphere. The most likely scenario is one with a rate of reduction in specific GHG emissions per capita of 0.5% / year, and a moderate increase of the absorbing capacity of forests mainly due to the implementation of forest-climate projects and fire emission reduction. Under the latter scenario, net GHG emissions by 2060 could reach 0.7 Gt CO2eq, which would require the creation of a national industry for large-scale carbon capture and storage in order to achieve climate neutrality of the Russian economy.
ELECTRONIC AND MAGNETIC PROPERTIES OF ALLOYS BASED ON THE DIRAC SEMIMETAL Cd3As2 DOPED BY Mn ATOMS WITH THE VARIABLE CONCENTRATIONS
Authors: Kulatov E. T. , Uspenskii Yu. A.
Published: April 2024

Theoretical studies predict that the low magnetic doping of the Dirac semimetals (DS) leads to the appearance in them of unusual quantum states and properties: the states of Weil semimetals, axionic insulator, topological superconductor and so on. However the specific materials in which these phenomena can be observed, as well as the characteristic concentrations of magnetic atoms are still unknown. In the present work, an ab initio study of the electronic and magnetic properties of the DS Cd3As2 doped isoelectronically with Mn atoms at concentrations of 4, 6, and 8% was performed. When analyzing the results, the main attention is paid to breaking spatial and time reversal symmetry in alloys, the behavior of the electronic structure near the top of the Dirac cone, and the processes of spin ordering in Mn atoms. The results obtained are compared with earlier theoretical and experimental studies, and on their basis a detailed picture of the effect of isoelectronic magnetic doping on the properties of the DS Cd3As2 is given.
PONDEROMOTIVE FORCES IN THE INTERACTION OF A CHARGED PARTICLE WITH AN INHOMOGENEOUS ELECTROMAGNETIC WAVE
Authors: Lapshin V. B. , Skubachevskii A. A. , Bugaev A. S.
Published: April 2024

In the article, based on the analysis of the features of the trajectory of a charged particle in an inhomogeneous electromagnetic wave, the physical processes that determine the nature of pondermotive forces are specified. In particular, the reason for changing the accelerated motion of a particle when passing through zero of the electric field amplitude in the direction perpendicular to the electric field to deceleration with increasing electric field amplitude is detailed. The influence of the inertial mass on the trajectory of a charged particle in an inhomogeneous electromagnetic wave is determined.
OPTIMIZATION OF THE MOTION OF A BODY WITH AN INTERNAL MASS UNDER QUADRATIC RESISTANCE
Authors: Chernousko F. L.
Published: April 2024

Rectilinear motion of a body controlled by a movable internal mass in a medium with a quadratic resistance is considered. Conditions are obtained that ensure translation of the body with a velocity changing periodically. The average speed of the motion is determined. Conditions that guarantee the maximum average speed are established.