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The last decade has seen dramatic progress in research on FETs with 2D channels. Starting from the single devices fabricated using exfoliated flakes in the early 2010s, by the early 2020s, 2D FETs being trialed for mass production and vertical stacking of 2D channels made by leading semiconductor companies. However, the industry is focused solely on transition metal dichalcogenide (TMD) channels coupled with conventional 3D oxide insulators such as Al2O3 and HfO2. This has resulted in numerous challenges, such as poor-quality interfaces and reliability limitations due to oxide traps. At the same time, the alternative routes for 2D FETs offered by laboratory (LAB) research have not been appreciated until now, even though the use of the native oxides of 2D channels has recently resulted in the first 2D FinFETs. Considering the research progress achieved in the last decade, from this perspective, we will discuss the main challenges for industry integration of 2D FETs and also suggest possible future steps which could propel these emerging technologies towards market applications. [ABSTRACT FROM AUTHOR]

We study linear models for the prediction of the initial guess for the nonlinear Newton-Raphson solver. These models use one or more of the previous simulation steps for prediction, and their parameters are estimated by the ordinary least-squares method. A key feature of the approach is that the parameter estimation is performed using data obtained directly during the simulation and the models are updated in real time. Thus we avoid the expensive process of dataset generation and the need for pre-trained models. We validate the workflow on a standard benchmark Egg dataset of two-phase flow in porous media and compare it to standard approaches for the estimation of initial guess. We demonstrate that the proposed approach leads to reduction in the number of iterations in the Newton-Raphson algorithm and speeds up simulation time. In particular, for the Egg dataset, we obtained a 30% reduction in the number of nonlinear iterations and a 20% reduction in the simulation time. [ABSTRACT FROM AUTHOR]

A comprehensive analysis of geological and geophysical data characterizing the structure of the eastern continental margin of India and the adjacent part of the bottom of the Bay of Bengal has been carried out. According to the structural and tectonic features, three sectors are distinguished: southern, central, and northern, the natural boundaries between which are the fault zones of the Makhanadi and Godavari–Krishna aulacogens. In the central sector, the pericontinental East Indian Plateau adjoins the continental slope. In 2003, the R/V Mezen acquired deep seismic sounding data on two profiles in this region. These data and their geological interpretation made it possible to identify "reduced" continental crust, characterized by reduced thickness of the upper, middle, and lower layers. A conclusion is drawn about the continental nature of the East Indian Plateau and northern part of the 85° Ridge adjacent to it. The light sialic and effusive rocks that form the top of the ridge give a negative gravimetric anomaly in the free-air reduction, which is its distinguishing feature. [ABSTRACT FROM AUTHOR]

The evolution of microstructure, phase composition and physico-mechanical properties of the biocompatible Ti-39Nb-7Zr alloy (wt.%) after severe plastic deformation by rotary forging (RF) was studied using various methods including light optical microscopy, scanning and transmission electron microscopies, X-ray diffraction, microindentation, tensile testing and investigation of thermophysical properties during continuous heating. The hot-rolled Ti-39Nb-7Zr with initial single β-phase structure is subjected to multi-pass RF at 450 °C with an accumulated degree of true deformation of 1.2, resulting in the formation of a fibrous β-grain structure with imperfect 500 nm subgrains characterized by an increased dislocation density. Additionally, nano-sized α-precipitates formed in the body and along the β-grain boundaries. These structural changes resulted in an increase in microhardness from 215 HV to 280 HV and contact modulus of elasticity from 70 GPa to 76 GPa. The combination of strength and ductility of Ti-39Nb-7Zr after RF approaches that of the widely used Ti-6Al-4V ELI alloy in medicine, however, Ti-39Nb-7Zr does not contain elements with limited biocompatibility and has a modulus of elasticity 1.5 times lower than Ti-6Al-4V ELI. The temperature dependences of physical properties (elastic modulus, heat capacity, thermal diffusivity) of the Ti-39Nb-7Zr alloy after RF are considered and sufficient thermal stability of the alloy up to 450 °C is demonstrated. [ABSTRACT FROM AUTHOR]

Solar filaments are well-known tracers of polarity inversion lines that separate two opposite magnetic polarities on the solar photosphere. Because observations of filaments began long before the systematic observations of solar magnetic fields, historical filament catalogs can facilitate the reconstruction of magnetic polarity maps at times when direct magnetic observations were not yet available. In practice, this reconstruction is often ambiguous and typically performed manually. We propose an automatic approach based on a machine-learning model that generates a variety of magnetic polarity maps consistent with filament observations. To evaluate the model and discuss the results, we use the catalog of solar filaments and polarity maps compiled by McIntosh. We realize that the process of manual compilation of polarity maps includes not only information on filaments, but also a large amount of prior information, which is difficult to formalize. To compensate for the lack of prior knowledge for the machine-learning model, we provide it with polarity information at several reference points. We demonstrate that this process, which can be considered as the user-guided reconstruction or superresolution, leads to polarity maps that are reasonably close to hand-drawn ones and additionally allows for uncertainty estimation. [ABSTRACT FROM AUTHOR]

The Mediterranean herb oregano is one of the most frequently adulterated foods. Often morphologically similar leaf material is used as a filler, which can generally be detected using DNA-based methods. Loop-mediated isothermal amplification (LAMP) has high potential for point-of-care testing as it requires only a simple device for sample incubation and is less sensitive to inhibition by co-isolated metabolites compared to conventional PCRs (polymerase chain reactions). In this work, we have developed two LAMP assays for the specific detection of the adulterants olive (Olea europaea) and strawberry tree (Arbutus unedo). The combination with a rapid isolation protocol and LFAs (Lateral-flow assays) as a visualization technique provides a reliable indication of possible adulteration. It has also been shown that it is possible to estimate the level of contamination and to perform the LAMP/LFA assay with DNA isolation in less than 30 min. As a further option, a duplex LAMP/LFA assay was developed that allows both contaminants to be detected in parallel, making the rapid test system even more cost-effective and user-friendly. [ABSTRACT FROM AUTHOR]

Background: Potocki-Lupski syndrome (PTLS, OMIM # 610883) is a rare genetic developmental disorder resulting from a partial heterozygous microduplication at chromosome 17p11.2. The condition is characterized by a wide variability of clinical expression, which can make its clinical and molecular diagnosis challenging. Case presentation: We report here a family (mother and her two children) diagnosed with PTLS. When examining children, neurological and psychological (neuropsychiatric) manifestations (speech delay, mild mental retardation), motor disorders, craniofacial dysmorphism (microcephaly, dolichocephaly, triangular face, wide bulging forehead, long chin, antimongoloid slant, "elfin" ears) were revealed. The suspected clinical diagnosis was confirmed by MLPA and CMA molecular genetic testing which revealed the presence of a segmental aneusomy; microduplication in the 17p11.2 region. Conclusions: Children with PTLS can have a clinically recognizable and specific phenotype: craniofacial dysmorphism, motor and neurological manifestations, which may implicate a possible genetic disease to the attending physician. Moreover, each child with this syndrome is unique and may have a different clinical picture. The management of such patients requires a multidisciplinary team approach, including medical genetic counseling. [ABSTRACT FROM AUTHOR]

Graphene is a promising material for applications as a channel in graphene field-effect transistors (GFETs) which may be used as a building block for optoelectronics, high-frequency devices and sensors. However, these devices require gate insulators which ideally should form atomically flat interfaces with graphene and at the same time contain small densities of traps to maintain high device stability. Previously used amorphous oxides, such as SiO2 and Al2O3, however, typically suffer from oxide dangling bonds at the interface, high surface roughness and numerous border oxide traps. In order to address these challenges, here we use 2 nm thick epitaxial CaF2 as a gate insulator in GFETs. By analyzing device-to-device variability for about 200 devices fabricated in two batches, we find that tens of them show similar gate transfer characteristics. Our statistical analysis of the hysteresis up to 175oC has revealed that while an ambient-sensitive counterclockwise hysteresis can be present in some devices, the dominant mechanism is thermally activated charge trapping by border defects in CaF2 which results in the conventional clockwise hysteresis. We demonstrate that both the hysteresis and bias-temperature instabilities in our GFETs with CaF2 are comparable to similar devices with SiO2 and Al2O3. In particular, we achieve a small hysteresis below 0.01 V for equivalent oxide thickness (EOT) of about 1 nm at the electric fields up to 15 MV cm−1 and sweep times in the kilosecond range. Thus, our results demonstrate that crystalline CaF2 is a promising insulator for highly-stable GFETs. [ABSTRACT FROM AUTHOR]

Abstract—The methods of scanning electron microscopy, X-ray diffraction analysis, and microindentation are used to study the effect of alloying with zirconium (within 3 to 6 at %) and complex Zr + Sn and Zr + Sn + Ta additions on the evolution of the structure, phase composition, and properties (effective modulus of elasticity, hardness, and wear-resistance parameters) of quenched biocompatible β-titanium (at %) Ti–26% Nb–3% Zr, Ti–26% Nb–5% Zr, Ti–26% Nb–6% Zr, Ti–26% Nb–3% Zr–1% Sn, and Ti–26% Nb–3% Zr–1% Sn–0.7Ta alloys during aging (at 400°C for 4, 16, and 64 h) after multipass cold rolling with a total degree of strain of 85%. As compared to the quenching, the cold rolling of the studied Ti–Nb–Zr alloys is shown to suppress the occurrence of the β → ω transformation in the course of aging and to favor the acceleration of the decomposition of β solid solution with the formation of nonequilibrium αl phase in the course of aging. The increase in the zirconium content from 3 to 6 at % in the cold-rolled ternary Ti–26% Nb – х% Zr alloys and introduction of complex Zr + Sn and Zr + Sn + Ta additions to the Ti–26% Nb alloy instead of only zirconium addition hinder the decomposition processes of the β phase during aging; this impacts the intensity of variations of the effective modulus of elasticity and microhardness. The aging of the cold-rolled alloys under study was found to allows us to obtain the higher values of the parameters H/Er and (Н is the hardness and Er is the resolved modulus of elasticity) associated with the wear resistance as compared to those for the widely used medical Ti–6Al–4V alloy. The compositions of the alloys and conditions of their treatment are determined, which allow us to obtain the combination of the highest-level properties. [ABSTRACT FROM AUTHOR]

The diagnosis of celiac disease (CD) is complex and requires a multi-step procedure (symptoms, serology, duodenal biopsy, effect of a gluten-free diet, and optional genetic). The aim of the study was to contribute to the improvement of CD diagnosis by preparing a water-soluble gluten peptide fraction (called Solgluten) and by selecting gluten-specific enzyme-linked immunosorbent assays (ELISA) for the detection of gluten immunogenic gluten peptides (GIPs) in urine and blood serum spiked with Solgluten. Food-grade Solgluten was prepared by the extraction of a peptic digest of vital gluten with water, centrifugation, and freeze-drying. The process was relatively easy, repeatable, and cheap. The content of gliadin-derived GIPs was 491 mg/g. Solgluten was used as antigenic material to compare two competitive ELISA kits (R7021 and K3012) and two sandwich ELISA kits (M2114 and R7041) in their quality regarding the quantitation of GIPs in urine and blood serum. The quality parameters were the reactivity, sensitivity, coefficients of variation and determination, and curve shape. The evaluation of the kits showed a number of discrepancies in individual quality parameters measured in urine and serum. Due to the lowest limit of quantitation and the highest coefficient of determination, M2114 may be the first choice, while R7021 appeared to be less suitable because of the high coefficients of variation and unfavorable curve progression. The results set the stage for improving CD diagnosis by supplementing conventional blood tests with oral provocation with Solgluten and subsequent ELISA measurement of GIPs that could support the no-biopsy approach and by better assessing the effect of a gluten-free diet by monitoring adherence to the diet by measuring GIPs in urine and blood. [ABSTRACT FROM AUTHOR]

Recent advances in fabricating field-effect transistors with MoS2 and other related two-dimensional (2D) semiconductors have inspired the industry to begin with the integration of these emerging technologies into FAB-compatible process flows. Just like in the lab research on 2D devices performed in the last decade, focus during development is typically put on pure technology-related issues, such as low-temperature growth methods of large-area 2D films on target substrates, damage-free transfer from sacrificial substrates and growth of top-gate oxides. With maturing technology, the problem of stability limitations caused by oxide traps is gradually coming into focus now. Thus, here we report an in-depth analysis of hysteresis and bias-temperature instabilities for MoS2 FETs fabricated using a 300 mm FAB-compatible process. By performing a comprehensive statistical analysis on devices with top gate lengths ranging between 18 nm and 10 μm, we demonstrate that aggressive scaling results in additional stability problems, likely caused by defective edges of the scaled top gates, in particular at higher operation temperatures. These are important insights for understanding and addressing the stability limitations in future nanoscale 2D FETs produced using FAB process lines. [ABSTRACT FROM AUTHOR]

5-Deazaflavins are analogs of naturally occurring flavin cofactors. They serve as substitutes for natural flavin cofactors to investigate and modify the reaction pathways of flavoproteins. Demethylated 5-deazaflavins are potential candidates for artificial cofactors, allowing us to fine-tune the reaction kinetics and absorption characteristics of flavoproteins. In this contribution, demethylated 5-deazariboflavin radicals are investigated (1) to assess the influence of the methyl groups on the electronic structure of the 5-deazaflavin radical and (2) to explore their photophysical properties with regard to their potential as artificial cofactors. We determined the proton hyperfine structure of demethylated 5-deazariboflavins using photochemically induced dynamic nuclear polarization (photo-CIDNP) spectroscopy, as well as density functional theory (DFT). To provide context, we compare our findings to a study of flavin mononucleotide (FMN) derivatives. We found a significant influence of the methylation pattern on the absorption properties, as well as on the proton hyperfine coupling ratios of the xylene moiety, which appears to be solvent-dependent. This effect is enhanced by the replacement of N5 by C5-H in 5-deazaflavin derivatives compared to their respective flavin counterparts. [ABSTRACT FROM AUTHOR]

Abstract—Differential thermal analysis, scanning electron microscopy, X-ray diffraction analysis, and microindentation are used to study changes in the structure, phase composition, microhardness, and contact modulus of elasticity of a heat-resistant alloy based on the Ti2AlNb titanium intermetallic compound, depending on the rate of colling (10–80°/min) from heating temperatures of 950 and 970°С. Using the results obtained, thermokinetic diagrams of high-temperature decomposition of the β(B2) solid solution are constructed. [ABSTRACT FROM AUTHOR]

The article provides systematization and comparative analysis of data for structure, phase composition, physical and mechanical properties formed within deformed pipes of semifinished products in different stages of preparing cold rolled pipes from hot-rolled pipe billets of titanium alloys PT–1M, PT–7M, Ti–3Al–2.5V. The effect of the degree of cold deformation on strain hardening of specimens from alloy hot-extruded pipes of semifinished products of the test alloys is established and on the basis of this recommendations are developed for maximum acceptable degree of deformation during cold rolling of pipes made of PT–1M, PT–7M, Ti–3Al–2.5V alloys. Deformation warming of alloys during cold rolling is evaluated. It is shown that cold rolling of pipes of the alloys studied into intermediate and final pipe workpieces with the reduction recommended contributes to the pipe strain hardening. When simulating cold rolling of pipes calculation of the Q-factor is carried out, which has a value of about 1. Cold rolling with such a value of Q-factor leads to formation of a texture of an inclined tangential prism alloying alloy from PT–1M to Ti–3Al–2.5V. It is noted that intermediate and final annealing at 680°C (PT–1M alloy), 750°C (PT–7M alloy, Ti–3Al–2.5V) of cold-rolled pipe billets studied facilitates alloy loss of strength as a result of occurrence of recrystallization and to the formation of a two-component texture {0001}±φ°TD<10–10>RD and {0001}±φ°TD<11–20>RD. Features of structure formation, phase composition, and mechanical properties of pipes in relation to alloying are considered. [ABSTRACT FROM AUTHOR]

This research paper is devoted to including new methods of approximation in Theory Of Approximation using Chebyshev Polynomials. The research focuses on creating a potential model for approximation using Neural Networks. This work enables mathematical analysis of the Chebyshev polynomials and activation functions. One of the goals of this paper was to minimize the time spent on the learning process. However, implementing every term of Chebyshev Polynomial could only be realized in some frameworks. [ABSTRACT FROM AUTHOR]

The article provides systematization and comparative analysis of data for structural and phase states and set of physical and mechanical properties formed in deformable tube semi-finished products. Analysis includes various stages of obtaining hot-extruded tubes of titanium alloys PT-1M, PT-7M, Ti–3Al–2.5V. The relationship between characteristics of macro-, microstructure, parameters of the phases formed with spread of hardness values in the original hot-forged tube billets is established. Physical simulation of hot deformation processes of alloys with varying temperature and upsetting deformation rate is conducted. Recommendations for extrusion temperature ranges for each alloy are proposed. These recommendations are based on energy-power parameters of industrial equipment used and restrictions imposed by the structure. Evolution of the structure and change in hardness during expansion of a tube billet made from the alloys investigated are considered. Results of computer simulations of energy-power parameters of tube extrusion and their comparison with industrial experiment data are presented. Features of the structure, texture and their relationship with tube mechanical properties are established. [ABSTRACT FROM AUTHOR]

The structure, the phase composition, and the physical and mechanical properties of a hot-forged billet from titanium alloy VT14 are studied by the methods of microstructural and x-ray diffraction analyses, micro-indentation, thermodynamic computations with the help of the ThermoCalc software, and thermomechanical tests in a Gleeble 3800 facility. The flow stress and the strain heating are shown to depend on the degree of deformation in compressive and tensile tests at strain rates 1 and 10 sec – 1 and temperatures 900, 925, 950, and 975°C. The results of the study are analyzed and compared to the available reported data. [ABSTRACT FROM AUTHOR]

Deazaflavins are important analogues of the naturally occurring flavins: riboflavin, flavin mononucleotide (FMN), and flavin adenine dinucleotide (FAD). The use of 5‐deazaflavin as a replacement coenzyme in a number of flavoproteins has proven particularly valuable in unraveling and manipulating their reaction mechanisms. It was frequently reported that one‐electron‐transfer reactions in flavoproteins are impeded with 5‐deazaflavin as the cofactor. Based on these findings, it was concluded that the 5‐deazaflavin radical is significantly less stable compared to the respective flavin semiquinone and quickly re‐oxidizes or undergoes disproportionation. The long‐standing paradigm of 5‐deazaflavin being solely a two‐electron/hydride acceptor/donor—"a nicotinamide in flavin clothing"—needs to be re‐evaluated now with the indirect observation of a one‐electron‐reduced (paramagnetic) species using photochemically induced dynamic nuclear polarization (photo‐CIDNP) 1H nuclear magnetic resonance (NMR) under biologically relevant conditions. [ABSTRACT FROM AUTHOR]

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French astronomer Honoré Flaugergues compiled astronomical observations in a series of handwritten notebooks for 1782–1830, which are preserved at Paris Observatory. We reviewed these manuscripts and encoded the records that contain sunspot measurements into a numerical table for further analysis. All measurements are timings, and we found three types of measurements, allowing the reconstruction of heliographic coordinates. In the first case, the Sun and sunspots cross vertical and horizontal wires; in the second case, one vertical and two mirror-symmetric oblique wires; and in the third case, a rhombus-shaped set of wires. Additionally, timings of two solar eclipses also provided a few sunspot coordinates. As a result, we present the time–latitude (butterfly) diagram of the reconstructed sunspot coordinates, which covers the period of the Dalton Minimum and confirms consistency with those of Derfflinger and Prantner. We identify four solar cycles in this diagram and discuss the observed peculiarities as well as the data reliability. [ABSTRACT FROM AUTHOR]

We study sequences of elements of an arbitrary field that satisfy decompositions of the form where . We prove some results concerning the existence and uniqueness of such sequences. The results are used to construct analogs of the Diffie–Hellman and ElGamal cryptographic algorithms. The discrete logarithm problem is considered in the group , where the set consists of quadruples , , and . [ABSTRACT FROM AUTHOR]

The article analyses data for chemical composition, manufacturing and processing methods for promising heat-resistant alloys based upon orthorhombic titanium intermetallic Ti2AlNb (O-alloys) developed within Russia and abroad. Phase diagrams typical for alloys based upon Ti–Al–Nb and general data for the phases formed in these alloys are provided. Concepts of aluminum and niobium equivalents used for multicomponent alloys are considered. The effect of alloying elements on a combination of mechanical properties of O-alloys, alloying principles, and compositions of the alloys developed are summarized. Characteristics of phase transformations occurring within alloys during heat treatment, including continuous heating and isothermal treatment, are provided. Typical microstructures of the alloys are presented; processing methods for their production and the influence of structural parameters on a combination of properties are described. Methods for manufacturing and processing routes of O-alloys are presented, which provide a good set of properties at room and elevated temperatures, as well as possible operating temperatures for refractory use. [ABSTRACT FROM AUTHOR]

In this contribution, the relative hyperfine couplings are determined for the 1H nuclei of the flavin mononucleotide (FMN) radical in an aqueous environment. In addition, three structural analogs with different methylation patterns are characterized and the influence of the substituents at the isoalloxazine moiety on the electronic structure of the radicals is explored. By exploiting nuclear hyperpolarization generated via the photo-CIDNP (chemically induced dynamic nuclear polarization) effect, it is possible to study the short-lived radical species generated by in situ light excitation. Experimental data are extracted by least-squares fitting and supported by quantum chemical calculations and published values from electron paramagnetic resonance and electron-nuclear double resonance. Furthermore, mechanistic details of the photoreaction of the investigated flavin analogs with l-tryptophan are derived from the photo-CIDNP spectra recorded at different pH values. Thereby, the neutral and anionic radicals of FMN and three structural analogs are, for the first time, characterized in terms of their electronic structure in an aqueous environment. [ABSTRACT FROM AUTHOR]

Using the calculation and experimental techniques, we studied the effect of cold rolling to degrees of 85 and 90% on the structural and textural condition, microdurometric and elastic properties of the following quenched biocompatible β-titanium alloys (in at %): Ti–26% Nb–3% Zr, Ti–26% Nb–5% Zr, Ti–26% Nb–6% Zr, Ti–26% Nb–3% Zr–1% Sn, Ti–26% Nb–3% Zr–1% Sn–0.7% Ta. It is shown that an increase in the degree of deformation at cold rolling promotes the formation of a more pronounced two-component texture {001}ββ, {112}ββ, a growth in the microhardness, and a decrease in the values of the elastic modulus in the plane of rolling. It is established that there is good agreement between the calculation and experimental values of the elastic modulus of these alloys in the quenched and cold-rolled state. The effect of alloying and anisotropic state of the alloys (via the molybdenum equivalent and the Zener anisotropy index, respectively) on the levels of their microhardness, contact elastic modulus E, including the difference in E in different sections of cold-rolled sheet,—is considered. Those compositions of alloys and the modes of deformation are determined that allow one to obtain the lowest values of their own elastic moduli. [ABSTRACT FROM AUTHOR]

Data are analyzed for chemical composition, preparation and processing methods, and fields of application for titanium pseudo-α- (Ti31, Ti75, CT20, TA15, Grade 9) and (α + β)-martensitic alloys (Grade9M, Grade23, Grade23M, VST3331, VT14, VT23) developed within Russia and abroad used for cold-deformed pipe manufacture. Characteristic alloying features are evaluated and production operation sequences used for different alloys in the manufacture of cold-rolled pipes are provided. Available experimental data about the effect of temperature-rate parameters of tensile and compressive deformation over a wide temperature range on maximum deformation forces of titanium "pipe" alloys or their analogues are considered. The influence of alloying, degree and rate of cold deformation on the change in the strength and ductility properties of these alloys is analyzed. Based on available data, the temperature range for annealing cold-rolled pipes is determined for the alloys in question, which provides a good combination of strength and ductility properties. Data are presented for the structure formed in different stages of pipe production, on the guaranteed set of properties, areas of their use, and development trends. [ABSTRACT FROM AUTHOR]

Epitaxial calcium fluoride (CaF2) layers with a nominal thickness up to 10 nm on the (111)-oriented Silicon (Si) are obtained. Surface topographies of the fluoride films are recorded and the current-voltage characteristics of the Au/CaF2/Si structures are studied. On a qualitative level, these structures exhibited all the features usual for metal-insulator-semiconductor systems. The current-voltage curves of the samples were reproduced by modeling considering a finite (0.1–1 nm) value of the standard thickness deviation of the dielectric CaF2 film. [ABSTRACT FROM AUTHOR]

Titanium alloys based on orthorhombic titanium aluminide Ti2AlNb are promising refractory materials for aircraft engine parts in the operating temperature range from 600–700 °C. Parts made of Ti2AlNb-based alloys by traditional technologies, such as casting and metal forming, have not yet found wide application due to the sensitivity of processability and mechanical properties in chemical composition and microstructure compared with commercial solid-solution-based titanium alloys. In the last three decades, metal additive manufacturing (MAM) has attracted the attention of scientists and engineers for the production of intermetallic alloys based on Ti2AlNb. This review summarizes the recent achievements in the production of O-phase-based Ti alloys using MAM, including the analysis of the feedstock materials, technological processes, machines, microstructure, phase composition and mechanical properties. Powder bed fusion (PBF) and direct energy deposition (DED) are the most widely employed MAM processes to produce O-phase alloys. MAM provides fully dense, fine-grained material with a superior combination of mechanical properties at room temperature. Further research on MAM for the production of critical parts made of Ti2AlNb-based alloys can be focused on a detailed study of the influence of post-processing and chemical composition on the formation of the structure and mechanical properties, including cyclic loading, fracture toughness, and creep resistance. [ABSTRACT FROM AUTHOR]

A method is proposed for including the effects of non-Gaussian velocity field distribution in the estimation of the growth rate of magnetic energy in a random flow with finite memory time. The method allows a reduction to the Gaussian case that was investigates earlier. For illustration, the multivariate Laplace distribution is considered and compared with the Gaussian one. [ABSTRACT FROM AUTHOR]

Helicobacter pylori extracts cholesterol from the host and converts it to its glycosides. We found that cholesteryl 6′‐O‐acyl α‐glucoside (ChAcαG) produced by H. pylori is recognised by both invariant Vα14+ NKT (iNKT) cells and a C‐type lectin receptor Mincle (Clec4e). However, it is unclear how these duplicated recognitions cooperate and contribute to host defence against H. pylori. Among T cell populations in the liver, iNKT cells predominantly expressed the T cell activation marker CD69 just after stimulation with ChAcαG. The production of IFN‐γ and IL‐4 was strictly dependent on both CD1d and Jα18 expressions, indicating the necessity of iNKT cell activation for the initiation of immune responses. Production of IFN‐γ by iNKT cells was markedly reduced by the Mincle deficiency on antigen‐presenting cells (APCs), while IL‐4 production was not significantly influenced. IL‐2 production by iNKT cell hybridomas was also diminished by the Mincle deficiency upon stimulation with APCs previously loaded with ChAcαG. Here, the immune responses of iNKT cell hybridomas stimulated with wild‐type APCs were reduced by the addition of anti‐IL‐12 blocking antibody to the level stimulated with Mincle‐deficient APCs. Collectively, these results suggest that iNKT cells can be activated with the cholesteryl glycosides via a Mincle‐dependent, IL‐12 signal‐dependent pathway and a Mincle‐independent, invariant TCR signal‐dominant pathway. iNKT cells activated via the Mincle‐dependent pathway produce IFN‐γ‐dominant cytokines; hence, they may contribute to enhancing proinflammatory responses against H. pylori infection. [ABSTRACT FROM AUTHOR]

Based on the data of deep seismic sounding, which were obtained in 2003 on the R/V Mezen in the Bay of Bengal, two velocity sections have been constructed that characterize the structure of the crust in its southern part. Seismic studies have shown that, in the Bengal sector of the East Indian Ridge (EIR), a subcontinental type of crust is developed, the thickness of which reaches 19.5 km. At the western foot of the EIR, the velocity section is represented by a reduced transitional crust 13 km in thickness. Using the NGDS digitized database of the thickness of the sedimentary cover in the Indian Ocean, which is freely available on the Internet, a map of the depths of the acoustic basement is built which makes it possible to identify the morphological features of its structure. A seismostratigraphic analysis is carried out of the structure of the sedimentary cover that has developed (a) on horst blocks grouped at the foot of the western slope of the EIR, (b) on the crest of the EIR, and (c) in the adjacent part of the Central Basin. It is established that, in the Late Cretaceous–Paleogene, the Bengal sector of the EIR and horst blocks represented a single platform structure. In the latest phase of tectonic activation, which manifested itself in the late Miocene–Pliocene, the platform was divided into horst blocks, which experienced differentiated subsidence. It has been established that horst blocks play the main role in the structure of Ridge 85°. This ridge is not structurally unrelated to the Afanasy Nikitin Rise and, by its nature, is not a "tracer ridge." [ABSTRACT FROM AUTHOR]

The results of calculations of the elastic properties of quenched biocompatible titanium based Ti–26% Nb, Ti–26% Nb–3% Zr, Ti–26% Nb–6% Zr, Ti–26% Nb–3% Zr–1%Sn, and Ti–26% Nb–3% Zr–1% Sn–0.7Ta alloys (in at %) are presented and compared with the literature and experimental data on estimating the elasticity modulus of alloys by microindentation. Microstructural and X-ray diffraction analysis showed that the studied alloys subjected to quenching from the β-region contain a single-phase metastable solid β-solution prone to twinning under cold deformation as follows from the location of the alloys in the Bo‒Md diagram. Good agreement has been established between the calculated and experimental values of the elastic properties, as characterized by an increase in the shear and Young moduli and a decrease in the Poisson coefficient with an increase in the molybdenum equivalent, which determines the stability of a solid alloy β‑solution. [ABSTRACT FROM AUTHOR]

In recent years evidence has been accumulated showing that miRNAs can act as potential biomarkers or targets for therapy of preterm birth, one of the most important problems in modern obstetrics. We have performed a prospective study of the miRNA profile in the plasma during the first and second trimesters in pregnant women with high risk of preterm birth (n = 13 cases and n = 11 controls). For the study group plasma blood samples at 9–13 weeks before diagnosis and at 22–24 weeks after start of therapy were selected. Using high-throughput sequencing technology we detected differences in the levels of 15 miRNAs (3 upregulated—hsa-miR-122-5p, hsa-miR-34a-5p, hsa-miR-34c-5p; 12 downregulated—hsa-miR-487b-3p, hsa-miR-493-3p, hsa-miR-432-5p, hsa-miR-323b-3p, hsa-miR-369-3p, hsa-miR-134-5p, hsa-miR-431-5p, hsa-miR-485-5p, hsa-miR-382-5p, hsa-miR-369-5p, hsa-miR-485-3p, hsa-miR-127-3p) (log2(FC) ≥ 1.5; FDR ≤ 0.05) during the first trimester compared with the control (non-high-risk of preterm birth pregnant women). All downregulated miRNAs in the first trimester from the placenta-specific C14MC cluster. During the second trimester no differentially expressed miRNAs were found. Our results suggest that the miRNA profile in plasma during early pregnancy may predict a high risk of preterm birth, which is important in preventing gestational problems as early as possible. [ABSTRACT FROM AUTHOR]

Computer simulation of the action of pressing deformation over a section of a tube from titanium alloy Grade 9 is performed. Acomputer model is used to determine the forces developed by the pressing tool during fabrication of the tube under a peak load and in a steady stage. The values computed are comparable to the experimental data obtained in actual production. The adequacy of the simulation is checked by comparative analysis of the evolution of the structure, texture, physical and mechanical properties in cross section of the hot-pressed tube. [ABSTRACT FROM AUTHOR]

The effect of continuous cooling at a rate of 1.1 K/min and combined cooling with an isothermal hold at 860 – 940°C on the structure, phase composition and properties of titanium alloy VTI-4 is studied. It is shown that introduction of an isothermal hold into the cooling mode lowers the hardness and elevates the content of untransformed β-phase in the structure of the alloy. The structure of the alloy is shown to be the most homogeneous without a feature of secondary decomposition yielding fine precipitates and with a maximum content of β-phase after an isothermal hold at 800°C for 1 h. [ABSTRACT FROM AUTHOR]

A new approach to millimeter-wave imaging was suggested and experimentally studied. This approach can be considered as the evolution of the well-established focal-plane array (FPA) millimeter-wave imaging. The significant difference is the use of a direct-conversion array receiver, instead of the direct-detection array receiver, along with the frequency-modulated continuous-wave (FMCW) radar technique. The sensitivity of the direct-conversion receiver is several orders higher than the sensitivity of the direct-detection one, which allows us to increase the maximum imaging range by more than one order of magnitude. The additional advantage of the direct-conversion technique is the opportunity to obtain information about the range to an object. The realization of the direct-conversion FPA imaging system was made possible due to original sensitive simple-designed receiving elements based on low-barrier Mott diodes. The suggested imaging method's main characteristics, which include the achievable angular and range resolution and the achievable maximum imaging range, were studied. A maximum range of up to 100 m was experimentally determined. A 94 GHz 8 × 8 imaging system was developed for demonstration purposes and studied in detail. The suggested technique is assumed to be useful for creating a long-range millimeter-wave camera, in particular, for robotic systems that operate in poor environmental conditions. [ABSTRACT FROM AUTHOR]

Purpose. Providing general characteristics, types and concepts of legal relations in the coal mine methane industry (CMM industry), revealing specific features of coalbed methane as an object of international, European and constitutional legal relations caused by its natural dichotomy as a harmful substance – greenhouse gas, on the one hand, and material and/or energy resource – a mineral of national importance, on the other. Methodology. During the research, general and special research methods such as dialectical, comparative legal, formal-legal, formal logical, comparative, system structural and system functional methods were used. Findings. It is proposed to differentiate economic activity in coal mine methane industry into types corresponding to the specifics of content, object composition and the legislation field regulating it. It is established that for mining and subsoil legal relations in the CMM industry, subsoil, mining and subsoil mining objects can act as generic objects in which coal mine methane to be extracted is concentrated. The authors’ understanding of the moment of transferring property to coal mine methane is reasoned, as well as its consideration as an object of law of property various forms, based on the connection of methane with subsoil. The main features of coalbed methane as a direct subject of constitutional and legal relations and as an object of international and European legal relations are determined. Originality. The classification of types of legal relations in CMM industry of the general level, based on the natural dichotomy of coal mine methane, has been developed. Definitions of “legal relations in CMM industry”, “environmental safety of objects of legal relations in CMM industry”, as well as the features of coalbed methane as part of the property of the Ukrainian people, world climate policy and European green course. Practical value. The practical significance of the results consists in the possibility of using them in research and educational activities by scientists and researchers in higher education, lawmaking, law enforcement and judicial practice in the process of improving national legislation, investigating and reviewing legal cases in the field of using and emitting coal mine methane. [ABSTRACT FROM AUTHOR]

Catalogs of the Zurich Observatory contain positional information on sunspots, prominences, and faculae in the late 19th and early 20th centuries. This database is given in handwritten tabular form and was not systematically analyzed earlier. It is different from the sunspot-number time series made in Zurich and was obtained with a larger telescope. We trained a neural-network model for handwritten text recognition and present the database of reconstructed coordinates. The database obtained connects the earlier observations by Spörer with later programs of the 20th century and supplements the sunspot-group catalogs of the Royal Greenwich Observatory. We also expect that the presented machine-learning approach and its deep capabilities will motivate the processing of a wide bulk of astronomical data, which is still given in nondigitized form or as plain scanned images. [ABSTRACT FROM AUTHOR]

The effect produced by the rate of heating to the aging temperature of 500°C on the character of phase transitions, the formation of a phase-structure state, and the change in hardness in the quenched Ti–10V–2Fe–3Al titanium alloy with different carbon contents has been studied by differential scanning calorimetry (DSC), scanning electron microscopy, X-ray diffraction analysis, and durometry. It has been shown that the change in the heating rate and carbon content of the alloy has an effect on the temperatures of the exothermic peaks of phase transitions associated with that the metastable solid β-solution formed under quenching decomposes in the process of heating. It has been established that a decrease in the rate of heating to the aging temperature from 40 to 10°C/min and an increase in the carbon content from 0.008 to 0.034 wt % in the quenched Ti–10V–2Fe–3Al alloy improves the dispersity of secondary phases formed after quenching and thereby promotes a growth in the alloy hardness. The effect of the heating rate and carbon content on the change in the parameters calculated by the full-profile analysis of X-ray diffraction pattern for the phases detected after treatment is considered. [ABSTRACT FROM AUTHOR]

The evolution of phase composition and hardness in the refractory titanium VT18U alloy (Ti–6.4Al–3.5Zr–2.6Sn–1Nb–0.6Mo–0.2Si) during aging for 1 h within a temperature range of 550–700°C has been studied by optical, scanning, and transmission electron microscopy; full-profile X-ray diffraction analysis; and durometry. An explanation is given to some specific features of changes in the crystal lattice constants (unit cell parameters) (β, α', αII, αI , and α2) calculated by means of full-profile analysis for the phases formed under high-temperature treatment at 915°C and further aging in alloy VT18U. It has been shown that a maximum hardness at 650°C in aged alloy VT18U is correlated with a maximum amount of α2-precipitates, which are formed at this temperature and detected by means of full-profile analysis. For an pilot VT18U-based alloy with an increased content of zirconium (7 wt %) and tin (4 wt %), some morphological features in the precipitation of αII and α2-phases have been established alongside with regularities of transformations due to doping with aluminum, zirconium, and tin in the phases (β, αII, αI, α2) formed during aging at 700°C for 100 h. [ABSTRACT FROM AUTHOR]

An analysis of the relative number of groups in cycles 21–24 based on the digitization of observations of sunspots at the Locarno Observatory (Locarno, Switzerland) was performed. In the Zurich classification of sunspot groups, there are classes from A to J. The classes correspond to the process of development and decay of sunspot groups. Class A and B groups correspond to single pores or small pore clusters (class A) and bipolar group (class B). For the reconstruction of solar indices, the relative number of groups (A + B) is of great importance. We found significant variations in the relative number of spot groups (A + B) in the activity cycles. If the relative number of groups (A + B) at the activity minima is 45–50%, then a decrease to 25–30% at the activity cycle maxima is observed. In the original spot index R, proposed by R. Wolf, pores were not considered, and many cores united by one penumbra were counted as one spot. After 1893, at the suggestion of A. Wolfer, the method of calculating the sunspot index changed. The pores and all individual cores in the spots began to be considered – this index is denoted by Rz. It is believed that between the spot indices of the Wolf (R) and Wolfer (Rz), there is a constant transition coefficient close to R/Rz = 0.6. We found that this assumption is incorrect, and R/Rz depends on the amplitude of the activity cycle, varying for the N19 cycle R19~ 0.34, and for the period of the grand minimum RMM ~ 0.64. [ABSTRACT FROM AUTHOR]

Sunspot groups observed in white light appear as complex structures. Analysis of these structures is usually based on simple morphological descriptors that only capture generic properties and miss information about fine details. We present a machine-learning approach to introduce a complete yet compact description of sunspot groups. The idea is to map sunspot-group images into an appropriate lower-dimensional (latent) space. We apply a combination of Variational Autoencoder and Principal Component Analysis to obtain a set of 285 latent descriptors. We demonstrate that the standard descriptors are embedded into the latent ones. Thus, latent features can be considered as an extended description of sunspot groups and, in our opinion, can expand the possibilities for research on sunspot groups. In particular, we demonstrate an application for the estimation of the sunspot-group complexity. The proposed parametrization model is generic and can be applied to investigation of other traces of solar activity observed in various spectral lines. [ABSTRACT FROM AUTHOR]