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Recently, progress has been made in fabricating diamond-based scintillators with integrated rare-earth luminescent particles. These luminescent particles are integrated into the bulk of diamond during their synthesis by chemical vapor deposition (CVD). However, the growth conditions include a chemically aggressive plasma environment and elevated temperatures, which results in the partial degradation of particles and a decrease in the intensity of their luminescence. Here, we investigate the effect of thermal annealing of luminescent EuF3 and SrF2:Eu powders in microwave plasma that simulates the growth conditions of polycrystalline diamond. It was found that silicon substrates act as efficient reducing agents that lead to the partial reduction of trivalent europium to divalent europium. When annealing occurs on a diamond substrate, the reduction processes proceed at a significantly slower rate. The observed luminescence spectra showed both Eu2+ and Eu3+ luminescence bands, which allows for a targeted tuning of the luminescence spectrum of europium in composites and can be used to fabricate detectors and visualizers of X-ray radiation using a visible signal from the desired combination of Eu2±/Eu3± ions. During plasma annealing in pure hydrogen at moderate temperatures (600 °C), an intensive hydrogenation of particles is observed. Such hydrogen plasma treatment of fluorides may be considered a promising route to fabricate hydrides of various metals. [ABSTRACT FROM AUTHOR]

In the paper, we consider a one-dimensional difference Schrödinger equation ψ(z+h)+ψ(z−h)+ λυ(z)ψ(z) = Eψ(z) with a periodic potential υ. In the case where the potential in a neighborhood of R is real analytic, as well as in the case where, the potential has a finite number of simple poles per period, for small values of the coupling constant λ, we describe the asymptotics of a monodromy matrix. [ABSTRACT FROM AUTHOR]

In geoarchaeological studies, there is an issue with distinguishing between natural and anthropogenic signals in pedological paleoarchives. With the pedostratigraphy of the Upper Paleolithic site of Kostenki 14, this issue is reflected by problems with the determination of features of pedogenic and pyrogenic processes. This issue was addressed by means of a thorough analysis of the magnetic properties of paleosols accompanied by micromorphological observations. Most of the humic samples were shown to be a result of pedogenesis, but two samples (a Paleolithic hearth sample and a sample from paleosol IIc) had features of intensely burnt material. The difference in the typical intensity of large‐scale (natural or human‐induced) and local‐scale anthropogenic fire allowed for suggesting that the magnetic properties of the burnt sample were the result of an anthropogenically controlled fire event, that is, a hearth. This study shows that the magnetic properties of paleosols can be used to differentiate anthropogenic activity, in particular—burning, from pedogenic processes. This indicator is especially helpful in finding disturbed combustion features when the hearth structure is lost. This methodology used to demonstrate the local human‐induced pyrogenic effect at the Upper Paleolithic site can contribute to the discussion of the niche construction effect of human activities in the Pleistocene. [ABSTRACT FROM AUTHOR]

We propose a quantum model of spinning black holes with integrable ring singularities. For the charged Kerr–Newman quantum metric, the complete regularization takes place at fixing of the maximal (cut-off) energy of gravitons, k UV reg = ℏ c ∕ R S reg . The domains of existence of one, two and several event horizons r q are shown depending on the parameters of modified Kerr and Kerr–Newman metrics. [ABSTRACT FROM AUTHOR]

Tin-Vacancy (Sn-V) colour centres in diamond have a spin coherence time in the millisecond range at temperatures of 2 K, so they are promising to be used in diamond-based quantum optical devices. However, the incorporation of large Sn atoms into a dense diamond lattice is a non-trivial problem. The objective of our work is to use microwave plasma-assisted chemical vapour deposition (CVD) to grow Sn-doped diamond with submicron SnO2 particles as a solid-state source of impurity. Well-faceted diamond microcrystals with sizes of a few micrometres were formed on AlN substrates. The photoluminescence (PL) signal with zero-phonon line (ZPL) peak for Sn-V centre at ≈620 nm was measured at room temperature (RT) and at 7 K. The peak width (full width at half-maximum) was measured to be 1.1–1.7 nm at RT and ≈0.05 nm at 7 K. The observed variations of ZPL shape and position, in particular, narrowing of PL peak at RT and formation of single-line fine structure at low-T, are attributed to strain in the crystallites. The diamond doping with Sn via CVD process offers a new route to from Sn-V colour centre in the bulk of the diamond crystallites. This article is part of the Theo Murphy meeting issue 'Diamond for quantum applications'. [ABSTRACT FROM AUTHOR]

The results of the search for and study of the Late Pleistocene soils in the north of Western Siberia are described. The theoretical basis is an ice-free model of the evolution of Pleistocene landscapes in the region, because the alternative model of its glacial cover excludes the preservation of paleosols. Glacial deposits are absent in this region, and paleosol levels are detectable in the sections of high river terraces exposing the Late and Middle Pleistocene sediments. They correspond to the chronointervals with landscape conditions favorable for pedogenesis; namely, soils of the (1) Kazantsevo thermochron (marine isotope-oxygen stage MIS5 overlying the Middle Pleistocene alluvium), (2) Karginsky interstadial (MIS3), and (3) the end of Sartan cryochron (MIS2). The pedogenetic interpretation of these paleosols is based on morphogenetic analysis, including micromorphological examination. According to this analysis, (i) the stage of taiga soil formation with clay illuviation in the polygenetic profile of MIS5 paleosol was replaced by a colder tundra phase with suprapermafrost gleying; (ii) characteristic of the MIS3 paleosols were tundra-steppe conditions, under which gleying and cryogenesis were combined with the neoformation of carbonates; and (iii) the paleosol level of the end of MIS2 was the result of tundra-swamp pedogenesis and included gleyed pedosediments that filled ice-wedge pseudomorphs. The latter fact allows us to identify the Late Sartan Taz–Nadym cryogenic soil horizon. The results are correlated with synchronous stratigraphic schemes for adjacent regions suggesting the construction of the soil–permafrost paleorecord for the north of Western Siberia. This is important, because the interpretation of the modern surface soils requires special approaches in order to take into account relict pedogenic horizons that are often found in their profiles. [ABSTRACT FROM AUTHOR]

Background: There is a growing body of evidence suggesting that botulinum toxin can alter proprioceptive feedback and modulate the muscle‐spindle output for the treatment of dystonia. However, the mechanism for this modulation remains unclear. Methods: We conducted a study involving 17 patients with cervical dystonia (CD), seven of whom had prominent CD and 10 with generalized dystonia (GD) along with CD. We investigated the effects of neck vibration, a form of proprioceptive modulation, on spontaneous single‐neuron responses and local field potentials (LFPs) recorded from the globus pallidum externus (GPe) and internus (GPi). Results: Our findings demonstrated that neck vibration notably increased the regularity of neck‐sensitive GPi neurons in focal CD patients. Additionally, in patients with GD and CD, the vibration enhanced the firing regularity of non‐neck‐sensitive neurons. These effects on single‐unit activity were also mirrored in ensemble responses measured through LFPs. Notably, the LFP modulation was particularly pronounced in areas populated with burst neurons compared to pause or tonic cells. Conclusion: The results from our study emphasize the significance of burst neurons in the pathogenesis of dystonia and in the efficacy of proprioceptive modulation for its treatment. Moreover, we observed that the effects of vibration on focal CD were prominent in the α band LFP, indicating modulation of pallido‐cerebellar connectivity. Moreover, the pallidal effects of vibration in GD with CD involved modulation of cerebro‐pallidal θ band connectivity. Our analysis provides insight into how vibration‐induced changes in pallidal activity are integrated into the downstream motor circuit. © 2023 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

The concept of the formation of a solute-sized cavity in a solvent is widely used in the theories of solvation processes; however, most of the studies of cavity formation using atomistic simulations were limited to water and hydrocarbon models. We calculated the Gibbs free energy of cavity formation ΔcavG for a structurally diverse set of 23 common organic solvents. For the calculation, molecular dynamics simulations of solvent boxes were conducted, and the Widom particle insertion method was applied. The results obtained with two different force fields for the same solvent were in good agreement with each other in most cases. The obtained cavity size dependences of ΔcavG allowed ranking the solvents by the free energy cost of creation of a cavity with a certain size. Surprisingly, this cost was somewhat higher in glycerol, formamide, and ethylene glycol than in water. In general, higher values of ΔcavG are observed for the solvents with a branched network of intermolecular hydrogen bonds and strongly polar aprotic solvents. The numerical results can be used to improve the accuracy of the calculation of the cavity term in non-aqueous continuum solvation models. [ABSTRACT FROM AUTHOR]

A series of dialkyl [aryl(hydroxy)methyl]phosphonates with various substituents at the phosphorus atom was obtained by the Abramov reaction. The structure of the isolated products was confirmed by IR and NMR spectroscopy, mass spectrometry, and X-ray diffraction analysis. All the obtained compounds demonstrated activity against B. cereus and S. aureus bacterial strains. [ABSTRACT FROM AUTHOR]

The ability to detect and monitor amyloid deposition in the brain using non-invasive imaging techniques provides valuable insights into the early diagnosis and progression of Alzheimer's disease and helps to evaluate the efficacy of potential treatments. Magnetic resonance imaging (MRI) is a widely available technique offering high-spatial-resolution imaging. It can be used to visualize amyloid deposits with the help of amyloid-binding diagnostic agents injected into the body. In recent years, a number of amyloid-targeted MRI probes have been developed, but none of them has entered clinical practice. We review the advances in the field and deduce the requirements for the molecular structure and properties of a diagnostic probe candidate. These requirements make up the base for the rational design of MRI-active small molecules targeting amyloid deposits. Particular attention is paid to the novel cryo-EM structures of the fibril aggregates and their complexes, with known binders offering the possibility to use computational structure-based design methods. With continued research and development, MRI probes may revolutionize the diagnosis and treatment of neurodegenerative diseases, ultimately improving the lives of millions of people worldwide. [ABSTRACT FROM AUTHOR]

Commercial processes for conversion of carbon-containing gases to syngas and hydrogen are considered. The techno-economic characteristics of the main hydrocarbon gas conversion processes (steam methane reforming, partial oxidation, autothermal reforming) used by world's leading chemical and petrochemical companies and implemented on the commercial or semicommercial scale are presented. The characteristics of these processes are analyzed. The processes of steam conversion, autothermal reforming, and partial oxidation of methane have specific predominant application fields depending on the feed composition and requirements to the composition of the syngas obtained. The steam conversion can ensure the maximal H2/CO molar ratio in the syngas obtained, and the processes of autothermal reforming and partial oxidation of methane do not require external heat supply to the reactor and are simple in implementation. Analysis of the syngas market shows that the main drivers of its progress can be the need for alternative resources and the stable demand of the chemical industry. [ABSTRACT FROM AUTHOR]

The issue of optimizing laser-plasma X-ray sources is still relevant. In this context, numerical simulation methods are very effective. A series of 2d PIC calculations using the EPOCH code were carried out. The laser pulse duration was 0.7 ps, the peak intensity was 3 × 1020 W/cm2, and silicon foil between 2 and 5 μm thick was used as a target. The conversion efficiency into the continuous X-ray spectrum was calculated. The results of comparison of numerical calculations with experimental measurements showed their satisfactory agreement. [ABSTRACT FROM AUTHOR]

Concentric ring exciton polariton condensates emerging under non-resonant laser pump in an annular trapping potential support persistent circular currents of polaritons. The trapping potential is formed by a cylindrical micropillar etched in a semiconductor microcavity with embedded quantum wells and a repulsive cloud of optically excited excitons under the pump spot. The symmetry of the potential is subject to external control via manipulation by its pump-induced component. In the manuscript, we demonstrate excitation of concentric ring polariton current states with predetermined vorticity which we trace using interferometry measurements with a spherical reference wave. We also observe the polariton condensate dynamically changing its vorticity during observation, which results in pairs of fork-like dislocations on the time-averaged interferogram coexisting with azimuthally homogeneous photoluminescence distribution in the micropillar. [ABSTRACT FROM AUTHOR]

This work is focused on the investigation of the X‐ray's interaction with the color centers in diamond. X‐rays have the high penetrating power of radiation, which allows performing unhindered modifications deeply in the bulk of diamond crystals. Herein, it is shown that X‐rays irradiation of diamond can change the charge states of its defects, including silicon‐vacancy (SiV) and nitrogen‐vacancy (NV) color centers. By studying low‐temperature absorption spectra, it is shown that negatively charged SiV− and NV− centers partially transform into neutrally charged SiV0 and NV0 centers, accordingly. In addition, new absorption lines are registered, which may belong to other charge states of color centers. The results open a new way for the study of charge states for defects in various crystals (not limited to diamond), as well as allow the control over the charge state of color centers for diamond‐based quantum optics. [ABSTRACT FROM AUTHOR]

A concentration series of Y3Al5O12:Ce solid solutions were prepared, and the composition demonstrating the highest X-ray luminescence intensity of cerium was identified. Based on the best composition, a series of luminescent diamond–Y3Al5O12:Ce composite films were synthesized using microwave plasma-assisted chemical vapor deposition (CVD) in methane–hydrogen gas mixtures. Variations in the amounts of the embedded Y3Al5O12:Ce powders allowed for the fine-tuning of the luminescence intensity of the composite films. [ABSTRACT FROM AUTHOR]

Inhibition of fibril formation is considered a possible treatment strategy for amyloid-related diseases. Understanding the molecular nature of inhibitor action is crucial for the design of drug candidates. In the present review, we describe the common kinetic models of fibril formation and classify known inhibitors by the mechanism of their interactions with the aggregating protein and its oligomers. This mechanism determines the step or steps of the aggregation process that become inhibited and the observed changes in kinetics and equilibrium of fibril formation. The results of numerous studies indicate that possible approaches to antiamyloid inhibitor discovery include the search for the strong binders of protein monomers, cappers blocking the ends of the growing fibril, or the species absorbing on the surface of oligomers preventing nucleation. Strongly binding inhibitors stabilizing the native state can be promising for the structured proteins while designing the drug candidates targeting disordered proteins is challenging. [ABSTRACT FROM AUTHOR]

Within the glacier-free scenario of the MIS 2 (Sartanian cryochron) environment in the north of West Siberia, it is important to search for the new regional paleoecological records and stratigraphic markers for this period. We studied large ice-wedge pseudomorphs filled with gleyic pedosediments developed on the high river terraces in the Nadym and Taz rivers basins as a tracer of the surface cryogenic and pedogenic processes during MIS 2. Field morphological observations and measurements, palynological analysis and radiocarbon dating of organic matter from soils and pedosediments were performed. Two sets of paleoecological indicators were discriminated: pseudomorph geometry evidence of the processes and conditions of ice wedge formation during the Last Glacial Maximum whereas the paleopedological and paleobotanic results from the fills recorded the environments of ice wedge melting at the end of MIS 2. Paleotemperatures 7–10 °C lower than at present are inferred during the major part of Sartanian, even at its end continuous permafrost persisted providing development of swampy tundra vegetation and cryohydromorphic palaeosols. We propose to define Taz-Nadym cryopedogenic horizon as a representative regional unit for MIS 2 and to correlate it with synchronous cryogenic and palaeosol units in Central and Eastern Europe. [ABSTRACT FROM AUTHOR]

A gas chromatographic headspace analysis method was used to experimentally determine gas-to-liquid partition coefficients and infinite dilution activity coefficients for two saturated (2,2,4-trimethylpentane, cyclooctane) and 3 unsaturated hydrocarbons (1,7-octadiene, 1-hexyne, 4-vinyl-1-cyclohexene), one aromatic hydrocarbon (propylbenzene), one haloalkane (1,3-dichloropropane) and four halobenzenes (fluorobenzene, chlorobenzene, 1,2-dichlorobenzene, bromobenzene), two cyclic ethers (tetrahydrofuran, 1,4-dioxane), two alcohols (1-propanol, 2-propanol), three alkyl acetates (ethyl acetate, butyl acetate, pentyl acetate), and one alkanenitrile (acetonitrile) dissolved in 2-pyrrolidone at 298.15 K. The experimental results of the headspace chromatographic measurements, combined with published solubility and infinite dilution activity coefficient data, were used to derive Abraham model correlations for describing solute transfer into 2-pyrrolidone. Mathematical correlations based on the Abraham model describe the observed partition coefficient and activity coefficient data to within 0.14 log10 units (or less). [ABSTRACT FROM AUTHOR]

This research provided a model of genesis of soils in North-West Siberia connecting the stages of their development to the main environmental changes over the Late Pleistocene and the Holocene. The "soil memory" showed that the studied soils had a complex polygenetic origin. A gleyed paleosol with signs of solifluction found at a depth of 2 m was most probably formed during the Marine Isotope Stage (MIS) 3 that is the Karginsky interstadial. The following stage, i.e., MIS2 – the Sartanian cryochron was characterized by the eolian sedimentation of silty material. In the Late Sartanian, new soil formation began in the silty parent material, with a strong platy cryogenic aggregation and grain size sorting. The warmer and more humid climate in the early Holocene induced clay illuviation and allowed for the formation of the argic horizon. Finally, the modern climatic conditions have caused ooidal cryogenic aggregation within upper horizons, however recent frost action has not been as strong as it was during the previous cold stage. Additionally, the modern pedogenesis included spodic and stagnic processes as well as clay mineral transformation. We suppose that such a model of soil evolution could be extrapolated to the northern Cis-Ural region, but not to the west in the Baltic region, where the dynamics of pedogenesis were different. [ABSTRACT FROM AUTHOR]

The goal of our work was to assess the ability of hybrid apple seedlings and their parent forms to maintain frost resistance during the thaw period, by using artificial freezing methods. Apple resistance was studied in the laboratory by modelling the damage factors of the frost resistance component III with the use of a climatic chamber. All of the studied hybrid apple seedlings from all used crossing combinations showed a sufficient level of frost resistance under modelling of a three-day artificial thaw (+2 °C) with subsequent temperature lowering to –25 °C. The damage of bark, cambium and wood in all of the studied hybrid seedlings was reversible and did not exceed a 2.0 point rating on a 5-point scale. The temperature rise up to +2 °C during three days in February did not cause the activation of growth processes in buds and bark and did not dramatically affect hybrid apple seedlings. According to the results of the artificial freezing, hybrid apple seedlings of the 6026 family ('Imrus' × 'Krasa Sverdlovska') and hybrids of the 6030 family ('Svezhest' × 'Pepin Orlovsky') showed the largest potential frost resistance after a thaw in winter. [ABSTRACT FROM AUTHOR]

We study Ge-doped polycrystalline diamond films synthesized, using microwave plasma chemical vapor deposition (CVD) in CH4-H2 base mixtures. We compare two sources of the dopant – gaseous monogermane (GeH4) and solid Ge plates. We investigate the structure and phase composition of the obtained films, using scanning electron microscopy, photoluminescence (PL), and Raman spectroscopy. We vary the precursor gas composition to maximize the intensity of the Germanium–vacancy (Ge-V) PL signal at 602 nm and discover that, using [C]-rich gas mixtures ([CH4]=20%), we are able to increase the intensity of Ge-V signal by two orders of magnitude in comparison with Ge-doped high-quality microcrystalline films of the same thickness but grown at [CH4]=4%. The attained results may be used for the fabrication of polycrystalline diamond films and plates with high concentrations of Ge-V centers, which may serve as source material for the fabrication of submicrometer-sized luminescent diamond particles for local optical thermometry. [ABSTRACT FROM AUTHOR]

In various placental mammals, the bidirectional exchange of cells during pregnancy can lead to the acquisition of genetically unique cells that can persist in both mother and child for decades. Over the years, it has become increasingly clear that this phenomenon, termed fetomaternal microchimerism may play key roles in a number of biological processes. In this perspective, we explore the concept of fetomaternal microchimerism and outline how fetal microchimeric cells are detected and immunologically tolerated within the maternal setting. Moreover, we discuss undertakings in the field that hint at the significant plasticity of fetal microchimeric cells and their potential roles in promoting maternal wound healing. Finally, we explore the multifaceted roles of fetal microchimeric cells in cancer development and progression. A deeper understanding of fetomaternal chimerism in healthy and diseased states will be key toward developing more efficient anti-cancer treatments and regenerative therapies. Fetomaternal microchimerism refers to the bidirectional exchange of cells during pregnancy that can lead to the acquisition of genetically unique cells in both mother and child. In this perspective, Sedov et al. discuss current understanding of fetomaternal microchimerism and the potential implications for maternal wound healing and cancer development. [ABSTRACT FROM AUTHOR]

The annealing treatment plays a crucial role in tailoring the properties of synthetic diamond materials, especially those doped with various elements in order to form specific color centers like nitrogen-vacancy (NV), silicon-vacancy (Si-V), germanium-vacancy (Ge-V), etc. This study delves into the annealing of 175 μm-thick Ge-doped polycrystalline diamond (PCD) films grown by microwave plasma-assisted chemical vapor deposition (MPCVD). Large-area PCD plate was cut into smaller equivalent 5 × 5 mm2 pieces, which were separately subjected to annealing in microwave plasma in H 2 atmosphere, to annealing in vacuum or to annealing under high-pressure high-temperature conditions (HPHT, 5.9 GPa, 2000 °C). The structure, phase composition and photoluminescence (PL) of samples before and after various annealing processes were investigated. All applied types of annealing enhance both the Si-V and Ge-V lines in PL at room temperature. Increasing annealing temperature leads to gradual decrease of full widths at half-maxima (FWHM) of diamond Raman peak (1332.5 cm−1), as well as Si-V (738 nm) and Ge-V (602 nm) PL peaks. In addition, the limitations for each type of annealing are established. The obtained results are crucial for the design of CVD-grown Ge-doped and Si-doped PCD materials that can be used for applications in photonics such as single photon sources, biomarkers, as well as for the fabrication of optical diamond thermometers. [Display omitted] • Ge-doped PCD film was grown by MPCVD and cut into series of equivalent samples. • Different samples were subjected to different types of annealing: in H 2 plasma, in vacuum, and in HPHT conditions. • The annealing resulted in lowering FWHM of Raman, XRD and PL peaks of samples. [ABSTRACT FROM AUTHOR]

Powders of single-phase solid solutions based on cerium-doped gadolinium-scandium-aluminum garnet were synthesized by coprecipitation from aqueous solutions followed by annealing at 1600 °C. The solubility limit of cerium in gadolinium-scandium-aluminum garnet was determined by X-ray powder diffraction and scanning electron microscopy. It has been demonstrated that the solubility limit of cerium depends not only on the concentration of scandium in the solid solution but also on the fraction of Sc3+ cations in the dodecahedral and octahedral positions of the garnet crystal lattice. Based on the X-ray luminescence spectra of Ce3+ (∼575 nm, 5d→4f transition) in single-phase samples, the composition (Gd 2.73 Ce 0.02 Sc 0.5 Al 4.75 O 12) with the highest X-ray luminescence was determined. A diamond composite "Diamond-GSAG:Ce" with Gd 2.73 Ce 0.02 Sc 0.5 Al 4.75 O 12 particles has been fabricated, which exhibits intense yellow X-ray luminescence, that is visible to the eye. The investigated class of composites is promising for applications in stable detectors and visualizers of high-intensity X-ray radiation in synchrotrons and free-electron lasers. [ABSTRACT FROM AUTHOR]

The Gulf of Mexico coastal plain contains one of the largest dune systems in Mexico. These dunes and particularly their paleosols contain valuable paleoenvironmental information, however this aspect has been poorly studied. Here, we present the preliminary results obtained from buried paleosols of coastal dune ridges in Veracruz with the aim to reconstruct the environmental conditions during their formation as well as the phases of stability (pedogenesis) and instability (sedimentation) of the landscape. Three profiles were studied in the areas of Punta Delgada, PD (in the north), Palma Sola, PS, and La Mancha, LM (in the south). The chronological frame was constructed by radiocarbon dating of paleosols organic matter and pedogenic carbonates, and by Optical Stimulated Luminiscence (OSL) dating for the dune sediments. For each section several paleosols levels were identified whose properties permitted the differentiation of pedogenetic trends as well as their periods of formation. Nevertheless, the three sections did not provide for a continuous record of pedogenesis and sedimentation, as most of the paleosols are truncated by erosion. PS is the most complete profile which is formed from Marine Isotope Stage (MIS) 5c to MIS 1, with especially well-developed Holocene paleosols. LM includes only paleosols developed during MIS 4 and MIS 3, and PD shows only one paleosol originated during MIS 2. Although, the chronology is not complete as it has been constructed with a few dates, we consider each section contains information from different chronological windows. The results demonstrate that the oldest paleosols formed under more humid conditions during MIS 5c to 5a and probably MIS 4. As the MIS 4 to MIS 2 paleosols contain pedogenic carbonates, we interpret drier climates or with higher evapotranspiration rates. Paleosols from the early Holocene exhibit vertic properties probably formed by seasonal climates. Soils from the Middle-Late Holocene are less developed, due to the activation of the dune sedimentation. The results found here are compared at a regional scale with the dune system in the northern Gulf of Mexico and Yucatan peninsula, revealing both synchronous and asynchronous systems of eolian dynamics. The major asynchrony relates to the Wisconsinian stage (MIS 4 to MIS 2) for which high intensity of dune development is documented in the Veracruz and northern coasts whereas no dunes of that age are found in the Yucatan peninsula. [ABSTRACT FROM AUTHOR]

We report on novel microcrystalline diamond-germanium composite films grown by microwave plasma-assisted chemical vapor deposition in CH 4 –H 2 -GeH 4 mixtures on Si substrate. The structure of the films, characterized with scanning electron microscopy, X-ray diffraction, Raman and photoluminescence spectroscopy, is found to strongly depend on the deposition temperature: the Ge grains compete with diamond crystallites upon growth at 750–800 °C, but vanish at higher temperatures of 850–950 °C due to enhanced growth rate of diamond matrix. The Ge grains nucleated on the (100) oriented Si wafer at 800 °C are in an epitaxial relationship with the substrate, while Si–Ge alloy forms at intermediate temperatures 850–900 °C. As both components are transparent in the infrared spectrum, the composite shows certain optical transmission for wavelengths λ > 10 μm. The films revealed a bright optical emission of GeV color centers at 601 nm wavelength due to diamond doping with Ge. From the calculation of the effective coefficient of thermal expansion for the diamond-Ge composites, we show that it can be tuned to be close to that for SiC or Si single crystals by appropriate choice of the Ge volume fraction in the composite, facilitating the integration of the semiconductor wafers with the diamond-based film. [Display omitted] [ABSTRACT FROM AUTHOR]

The results of theoretical and experimental studies aimed at ensuring long-term stability of the power of a subterahertz gyrotron when tuning the generation frequency are presented. Power stabilization is performed via the coordinated change in the technical parameters of the generation mode. Two pairs of such parameters are considered: the accelerating voltage and the temperature of the resonator coolant or the magnetic field and the temperature of the resonator coolant. As a result of experiments performed with a subterahertz gyrotron of a kilowatt power level, power stability was demonstrated at a level of several percent with a frequency tuning range of more than 100 MHz, which confirms the correctness of the proposed approaches. [ABSTRACT FROM AUTHOR]

An analysis of the literature data indicates a wide front of research and development in the field of the use of methane–hydrogen mixtures as a promising environmentally friendly low-carbon fuel. The conclusion of most works shows that the use of methane–hydrogen mixtures in internal combustion engines improves their performance and emission characteristics. The most important aspect is the concentration of hydrogen in the fuel mixture, which affects the combustion process of the fuel and determines the optimal operating conditions of the engine. When using methane–hydrogen mixtures with low hydrogen content, the safety measures and risks are similar to those that exist when working with natural gas. Serious logistical problems are associated with the difficulties of using the existing gas distribution infrastructure for transporting methane–hydrogen mixtures. It is possible that, despite the need for huge investments, it will be necessary to create a new infrastructure for the production, storage and transportation of hydrogen and its mixtures with natural gas. Further research is needed on the compatibility of pipeline materials with hydrogen and methane–hydrogen mixtures, safety conditions for the operation of equipment operating with hydrogen or methane–hydrogen mixtures, as well as the economic and environmental feasibility of using these energy carriers. [ABSTRACT FROM AUTHOR]

Network-Based Approaches for Disease-Gene Association Prediction Using Protein-Protein Interaction Networks. The authors evaluate the accuracy of disease-gene association prediction and determine that integrative approaches outperform other methods in the presence of known disease-associated genes. The contribution of Magnez et al. [[9]] describes microscale thermophoresis (MT) as a technique to study protein-protein as well as protein-ligand interactions. [Extracted from the article]

The review examines the methods to evaluate the economic efficiency of various hydrogen production methods, including technologies to obtain hydrogen from natural gas (steam conversion, autothermal reforming, and combined methods) and other methods, currently proposed for application. A comparative analysis of the published data, studying the economics and the technical and economic indicators of hydrogen production, is carried out on the basis of modern mathematical modeling and computer data processing methods. The prospects of continuing the research in this area, especially in the development of small-scale production technologies, are noted; in the meantime, at present, natural gas can be considered as one of the most promising raw materials for hydrogen production. [ABSTRACT FROM AUTHOR]

• Pallidal single-neuron discharges are abnormal in dystonia. • Neurons have different isolated discharge pattern at deep brain stimulation responsive pallidal regions. • The differences in deep brain stimulation responsive regions are also evident in local field potentials. In patients with cervical dystonia we sought for the differences in neuronal behavior of pallidal regions where deep brain stimulation resulted in favorable therapeutic response compared to those where the response was absent. We compared single-unit activity of 564 neurons recorded from deep brain stimulation sensitive and non-sensitive regions in 17 cervical dystonia patients. Globus pallidus internus regions responsive to the deep brain stimulation had lower firing rates and bursting compared to non-responsive areas. The differences were robust in locations where neuronal responses correlated with neck movements. Per the effects of deep brain stimulation, the pallidal regions were classified in weak, intermediate, and excellent responsive. Pallidal regions with weak response to deep brain stimulation had fewer burst neurons and higher firing rate compared to neurons in areas with excellent response. The burst index was significantly decreased in excellent response regions. There was a significant decrease in the alpha band oscillation score but a substantial increase in the gamma band in excellent response neurons. The pallidal region that would be responsive to deep brain stimulation has distinct physiology compared to the non-responsive region. These results provide novel insights into globus pallidus interna neurons' physiology in cervical dystonia. [ABSTRACT FROM AUTHOR]

We combine the nonlinear Fourier transform (NFT) signal processing with machine learning methods for solving the direct spectral problem associated with the nonlinear Schrödinger equation. The latter is one of the core nonlinear science models emerging in a range of applications. Our focus is on the unexplored problem of computing the continuous nonlinear Fourier spectrum associated with decaying profiles, using a specially-structured deep neural network which we coined NFT-Net. The Bayesian optimisation is utilised to find the optimal neural network architecture. The benefits of using the NFT-Net as compared to the conventional numerical NFT methods becomes evident when we deal with noise-corrupted signals, where the neural networks-based processing results in effective noise suppression. This advantage becomes more pronounced when the noise level is sufficiently high, and we train the neural network on the noise-corrupted field profiles. The maximum restoration quality corresponds to the case where the signal-to-noise ratio of the training data coincides with that of the validation signals. Finally, we also demonstrate that the NFT b-coefficient important for optical communication applications can be recovered with high accuracy and denoised by the neural network with the same architecture. [ABSTRACT FROM AUTHOR]

We predict the spontaneous symmetry breaking in a spinor Bose–Einstein condensate of exciton-polaritons (polaritons) caused by the coupling of its spin and orbital degrees of freedom. We study a polariton condensate trapped in a ring-shaped effective potential with a broken rotational symmetry. We propose a realistic scheme of generating controllable spinor azimuthal persistent currents of polaritons in the trap under the continuous wave optical pump. We propose a new type of half-quantum circulating states in a spinor system characterized by azimuthal currents in both circular polarizations and a vortex in only one of the polarizations. The spontaneous symmetry breaking in the spinor polariton condensate that consists in the switching from co-winding to opposite-winding currents in opposite spin states is revealed. It is characterized by the change of the average orbital angular momentum of the condensate from zero to non-zero values. The radial displacement of the pump spot and the polarization of the pump act as the control parameters. The considered system exhibits a fundamental similarity to a superconducting flux qubit, which makes it highly promising for applications in quantum computing. [ABSTRACT FROM AUTHOR]

Experimental results on the parameters of detonation process formation in plastic-bonded HMX as functions of the velocity and size of spherical impactors are reported. Data on the threshold velocity of the impactor resulting in detonation initiation and on the length of the pre-detonation region in the velocity range from 882 to 1333 m/s are obtained. The results are compared with available experimental data on the length of the pre-detonation region for plane shock waves. The radio interferometry method of registration of the evolution of the explosion process initiated by the impactor is demonstrated to be fairly informative. [ABSTRACT FROM AUTHOR]

The review analyzes the development of the hydrogen energy market, discusses the national programs to support this new branch of the global energy industry and pilot hydrogen projects. The issues of hydrogen production, consumption, accumulation, storage, and transportation are considered. The assessment of the state of the global and Russian hydrogen markets according to main market indicators and their development prospects for the coming years is given. [ABSTRACT FROM AUTHOR]

Background Aim Methods Results Conclusions Imaging techniques of analysis in undisturbed soil samples are powerful tools for understanding soil properties and functioning. Although micromorphological analysis has always been applied for studying soil genesis, the modern 3D X‐ray Computed Tomography (CT) approach is mostly used in soil physical studies related to soil functioning and ecological services.In this study, we interpret ancient soil formation of the Late Pleistocene pedosedimentary archive of the Tlalpan sequence in the State of Tlaxcala in Central Mexico, based on soil and sediment porosity distribution in 2D and 3D.In order to interpret ancient soil formation based on the porosity distribution, we applied both micromorphological (2D) and CT (3D) analyses in undisturbed samples of each horizon of the Tlalpan sequence.Our micromorphological observations have shown that pore space arrangement is unique for each soil horizon and that it is predetermined by the dominant pedogenetical processes and their succession, such as bioturbation, clay illuviation, and vertic shrinking/swelling. Most of the channels formed by biogenic agents (roots and mesofauna) subsequently underwent shape deformations and/or refilling. The “accommodating planes” type of voids resulted from the development of features of vertic paleosols that, in some cases, erased the past pedogenic pore space organization. Although biogenic turbation, compaction, and clay illuviation mostly affected the macro‐ and mesopores, shrinking/swelling processes affected macro‐ and mesoporosity distribution. The process that was only reflected at the microporosity level is hydroconsolidation.Despite the common idea that textural pores are more resistant to changes compared to meso‐ and macropores, most of soil formation processes registered in the Tlalpan sequence, including anthropogenic impact, were identified in macro‐ and mesopore space. Moreover, the changes that were registered in pore space transformation by 2D and 3D methods of analysis in undisturbed samples are crucial for identifying the sequence of formation processes and, therefore, for paleopedological interpretation. This study shows that the CT is a useful tool to access the soil formation, and pore space memory studied both in 3D and 2D is an important proxy for paleopedological research. [ABSTRACT FROM AUTHOR]

The soil mantle of the tropical karstic landscapes of Southern Mexico was shaped by specific processes of pedogenesis and long-term human impacts of ancient Maya agriculture. To understand the interaction between natural and human-induced soilforming processes in the calcareous mountains of Chiapas state, we studied soil toposequences around the Classic Maya site of Budsilhá and related them to the archaeological evidence of settlement and land-use distribution. Soil chemical analysis, micromorphological observations, and clay mineral identification were carried out in key soil profiles at the main geoforms. Limestone hills are occupied by shallow Rendolls which are usually perceived as incipient soils. However, high content of silicate clay composed of kaolinite and vermiculite and ferruginous clayey soil material observed at macro- and microscale backed the hypothesis that these soils were formed from the residues of thick Terra Rossa after their erosion. Swampy lowlands are occupied by thick clayey gleyic soils with clay mineral assemblages similar to those in the upland Rendolls. We suppose that the mineral matrix of the lowland soils is largely derived from the pedosediments of eroded upland Terra Rossa, which lost original ferruginous pigmentation and aggregation due to redoximorphic processes. Some wetland soils contain neoformed gypsum that is atypical for humid tropics; sulfidesulfate transformation under fluctuating redox conditions could promote gypsum synthesis. Ancient Maya land use was closely related to soil-geomorphic conditions: settlements with homegardens occupied calcareous hills, whereas the primary agricultural domain was developed on lowland soils after their drainage by artificial canals. [ABSTRACT FROM AUTHOR]

State of the art in the field of the development of catalytic reactors for dehydrogenation of liquid organic hydrogen carriers is analyzed. Rapid and complete dehydrogenation and the possibility of repeated use of the carrier can be ensured by intensifying the heat exchange and reducing the dehydrogenation temperature; these factors should be taken into account in choosing the reactor design. Examples of using reactors with fixed, suspended, and monolithic catalysts, membrane reactors, reactors operating in the reactant vaporization/condensation modes, etc., and also universal reactors for hydrogenation/dehydrogenation of liquid organic hydrogen carriers are considered. A comparative analysis of the advantages and drawbacks of various reactor systems is made. [ABSTRACT FROM AUTHOR]

The review analyzes the published data on scientific, applied, and marketing studies on the development of modern synthetic bases of motor oils as marketable products. The conventional world-accepted classifications and performance characteristics of base oils are considered. The main trends in scientific research on the development of effective synthetic bases of motor oils and prospects for their further development are presented. The assessment of the state of the global and Russian motor oil markets according to major market indicators is given; the market development forecast for the coming years is presented. [ABSTRACT FROM AUTHOR]

X-ray luminescent diamond composite films with embedded yttrium-aluminum nanoparticles were designed. Additionally, the stability limits of single-phase solid solutions in systems based on yttrium-aluminum and yttrium-scandium-aluminum garnets doped with cerium were determined. The most intense X-ray luminescence was achieved with the [Y 2·98 Ce 0.02 ]{Al 2 }Al 3 O 12 powder. The composition-optimized nanoparticles were embedded into a polycrystalline diamond matrix to form a diamond-YAG:Ce composite. For the obtained composite, an intense X-ray luminescence from the Ce3+ ions near 550 nm was demonstrated. The designed composites may be used as adjustable and durable scintillating materials for a wide range of applications. [ABSTRACT FROM AUTHOR]

A procedure allowing preparation of mixed metal–carbon nanostructures from electroplating waste in a high yield was suggested. The following substances containing all the metals from the initial slime can be prepared from electroplating slimes (containing mainly iron or copper): metal phthalocyanines, phthalocyanine pyrolyzates, mixed endometallofullerenes, and their hydroxylated derivatives. [ABSTRACT FROM AUTHOR]

Objective/Background: The current study identified heterogeneous trajectories of insomnia symptoms from early pregnancy to early postpartum. The relationship between demographic and psychological predictors of trajectories and associations between trajectory group membership and symptoms of postpartum depression and anxiety were also explored. Participants: 142 pregnant women were enrolled in a prospective online survey. Method: Women were recruited from a maternity clinic in Calgary, AB and completed measures of insomnia symptoms, depression, generalized anxiety, and interpersonal support at four time-points. Women were recruited and completed the first survey before 20 weeks gestation and were reassessed every 10 weeks. Women were on average 15 weeks gestation, 25 weeks gestation, 35 weeks gestation, and 6 weeks postpartum at the respective time-points. Group-based trajectory analysis was used to determine trajectories of pregnancy insomnia symptoms. Results: Three trajectory groups were identified. A no insomnia group (42.3%) in which women reported consistently low insomnia symptoms. A subclinical insomnia group (44.3%) in which women reported subclinical symptoms which briefly elevated to clinical levels in late-pregnancy, and a clinical insomnia group (13.4%) in which women reported consistently elevated insomnia symptoms. Baseline predictors of membership group included anxiety, depression, and ethnicity such that members of the clinical insomnia group were more likely to also endorse anxiety and depression. Membership in the clinical insomnia group was associated with higher postpartum generalized anxiety and depressive symptoms. Additionally, the clinical insomnia group were more likely to experience symptoms indicative of clinically significant depression. Conclusions: A small group of pregnant women experienced consistently high and elevated insomnia symptoms throughout pregnancy and another larger group endorsed consistently elevated but subthreshold symptoms. Future studies should explore long-term consequences of experiencing high insomnia symptomatology during pregnancy and early postpartum, as well as safe and efficacious interventions. [ABSTRACT FROM AUTHOR]

The diamond composite materials with embedded yttrium-aluminum garnet doped with cerium (YAG:Ce) nanoparticles have been produced by microwave plasma-assisted chemical vapor deposition (CVD). Nanoparticles were synthesized by co-precipitation from an aqueous solution while CVD diamond served as the transparent matrix with high thermal conductivity, hardness, and resistivity to radiation damage. The composite films show high-intensity X-ray luminescence (XRL) with a broad band peaking around the wavelength of 550 nm (5d → 4f transition in Ce3+ ion), and a narrow peak of silicon-vacancy (Si–V) centers at 738 nm. The characteristic decay time was measured at τ Ce < 50 ns for cerium emission and at τ SiV ∼1 ns for Si–V centers. Excitation spectra of both luminescence types measured near yttrium K-edge (17.1 keV) show a strong correlation, attributed to the excitation of Si–V luminescence by photoelectrons ejected from YAG:Ce nanoparticles. The discovered phenomenon suggests a new way to control X-ray visualization by luminescent diamond composites for fast X-ray detectors and screens. Image 1 [ABSTRACT FROM AUTHOR]

Focal dystonia, by definition, affects a specific body part; however, it may have a widespread neural substrate. We tested this hypothesis by examining the intrinsic behaviour and the neuronal properties that are modulated by changes in the physiological behaviour of their connections, that is feedback dependence, of the isolated pallidal neurons. During deep brain stimulation surgery in 12 patients with isolated cervical dystonia (without hand involvement), we measured spontaneous as well as evoked single‐unit properties in response to fist making (hand movement) or shoulder shrug (neck movements). We measured the activity of isolated neurons that were only sensitive to the neck movements, hand movement, or not responsive to hand or neck movements. The spontaneous firing behaviour, such as the instantaneous firing rate and its regularity, was comparable in all three types of neurons. The neck movement‐sensitive neurons had prominent bursting behaviour in comparison with the hand neurons. The feedback dependence of the neck movement‐sensitive neurons was also significantly impaired when compared to hand movement‐sensitive neurons. Motor‐evoked change in firing rate of neck movement‐sensitive neurons rapidly declined; the decay time constant was much shorter compared to hand movement‐sensitive neurons. These results suggest that in isolated cervical dystonia, at the resolution of single neurons, the deficits are much widespread, affecting the neurons that drive the neck movement as well as the hand movements. We speculate that clinically discernable dystonia occurs when additional abnormality is added to baseline dysfunctional network, and one source of such abnormality may involve feedback. [ABSTRACT FROM AUTHOR]

The review provides a comparative analysis of the basic technologies for production of bimodal polyethylenes by the leading world companies, their technical characteristics, and the applied catalysts and reactor systems; the preferred application areas of bimodal polyethylenes are also considered. The global bimodal polyethylene producers and the leading licensors of polyethylene technologies are presented. The state and development prospects of the global and regional polyethylene markets are studied; the market development forecast for the coming years is given. [ABSTRACT FROM AUTHOR]

The authors continued their research on the development of an intelligent automatic ships pilot containing a controller based on fuzzy logic. Its features are determined by the optimizer based on a genetic algorithm. It also contains a modular unit of neural network models of ship navigation paths, as well as a neural network classifier. This paper is devoted to the description of a neural network classifier designed to classify the movement patterns of marine vessels to identify the peculiarities of the ship depending on its type and sailing conditions. The introduction of such classifier to an autopilot allows for more precise consideration of multivariate and difficult to formalize factors affecting the vessel while operating, such as varying weather conditions, irregular waves, hydrodynamic characteristics of the vessel, draft, water under the keel, rate of the vessel sailing, etc. The article outlines the technique concerning the development of a neural network classifier and the results of its computer modelling on the example of a refrigerated transport vessel type. The authors used such methods for obtaining and processing findings as spectral estimation, machine learning methods, in particular, neural network technology and computer or simulation modelling. [ABSTRACT FROM AUTHOR]

Gibbs free energy of cavity formation at 298 K against cavity radius rc totally excluding heavy solvent atoms for some solvent models. 3 and 5 of the original article.[2] We have taken solvent heavy atom radii equal to 1.9 nm and water oxygen radius equal to 1.4 nm and considered four solvents: ethylene glycol, pyridine, toluene, and water. The surface tension of a solvent is the quantity responsible for the energy cost of formation of macroscopic cavities, and it is indeed larger in water than in other solvents including ethylene glycol. [Extracted from the article]