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The observed absence of the small-t oscillations in differential cross-section of the elastic scattering is considered as a consequence of the reflective scattering mode appearance at the highest energy of the LHC s = 1 3 TeV. [ABSTRACT FROM AUTHOR]

The notion of cumulative activity for elastic events in hadron collision is introduced. The interrelation between centrality and cumulative activities of the elastic and inelastic events has been established for hadron scattering. Considerations on its application are presented. [ABSTRACT FROM AUTHOR]

The paper presents the results of scanning of mechanical properties of coniferous (common pine Pinus sylvestris) and deciduous (small-leaved lime Tiliacordata and common oak Quercus robur) trees wood using nanoindentation on crosscut face. Manifold increase in microhardness H and Young's modulus E has been observed between early and late wood in every annual growth ring. Significant differences in intraring radial dependencies of H and E have been found among studied species. For all studied species the average values of E and H of early wood in each annual ring are found to be independent from ring width, while such dependence for late wood is weak at most. The ring widths measured by nanoindentation coincide with the ones measured by standard optical method within 2–3%. The developed technique and obtained results can be useful (1) to amend the understanding the origins of macromechanical properties of various wood species and their dependence upon microstructural characteristics and growth conditions, (2) to optimize the technologies of growing, reinforcement and subsequent usage of the wood, (3) to develop new independent high resolution methods in dendrochronology. [ABSTRACT FROM AUTHOR]

The low-temperature behavior of the heat capacity and photoluminescence of the earlier structurally characterized binuclear pivalate complex [Eu2(Bath)2(Piv)6] (monoclinic crystal system, I2/a) (I), where Bath = 4,7-diphenyl-1,10-phenanthroline, Piv = , is studied. The temperature dependence of the heat capacity in a temperature range of 5.96–302.88 K is measured by adiabatic calorimetry, and the thermodynamic functions (T), S°(T), Ф°(Т), and Н°(Т) – Н°(0) are calculated. The absence of low-temperature phase transitions in complex I is shown. In a temperature range of 98–295 K, complex I demonstrates a high temperature stability of the integral photoluminescence intensity of the 5D0–7Fj (j = 0–6) transitions of the Eu3+ ion. [ABSTRACT FROM AUTHOR]

Epicuticular hydrocarbons from the Siberian population of Colorado beetle (Leptinotarsa decemlineata) formed eight isomeric homologous series of' mono-, di-, and trimethyl-branched alkanes with C26–C37 main-chain lengths. The major group of isomeric homologous series comprised terminally branched hydrocarbons with branching at the 2-position that were synthesized from valine (51% of the cuticular lipids). A second direction was the synthesis of internally branched alkanes with an acetyl-CoA primer (18%). Isomeric homologous series of hydrocarbons synthesized from propionyl-CoA accounted for 4%. [ABSTRACT FROM AUTHOR]

Thermodynamic properties of polycrystalline powders of ruthenium dichalcogenides have been studied using calorimetric isobaric heat capacity measurements in a wide temperature range. The adiabatic and differential scanning calorimetry data for ruthenium disulfide and ruthenium diselenide have been used to determine standard thermodynamic functions (heat capacity, entropy, enthalpy increment, and reduced Gibbs energy) of these compounds in the range 10–965 K. At 298.15 K, the functions of RuS2 are as follows: = 60.82 ± 0.12 J/(K mol), S° = 56.05 ± 0.11 J/(K mol), Н°(298.15 K) − Н°(0) = 9.75 ± 0.02 kJ/mol, and Ф° = 23.34 ± 0.05 J/(K mol). For RuSe2, we have obtained = 69.96 ± 0.14 J/(K mol), S° = 80.62 ± 0.16 J/(K mol), Н°(298.15 K) − Н°(0) = 13.05 ± 0.03 kJ/mol, and Ф° = 36.85 ± 0.08 J/(K mol). The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. The absolute entropies obtained in this study for the ruthenium dichalcogenides, in combination with literature data, have made it possible to evaluate the Gibbs energy of formation of RuS2(cr) and RuSe2(cr) at 298.15 K. [ABSTRACT FROM AUTHOR]

We introduce the notion of cumulative activity for inelastic events generated under hadron collisions, and discuss its energy dependence and connection with the reflective scattering mode. These issues are relevant for enlightening the asymptotic dynamics in view of the LHC measurements. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of crystalline ruthenium ditelluride (RuTe2) and its thermodynamic properties in the range from 10 to 965 K, evaluated from its isobaric heat capacity Cp determined using calorimetry. At low temperatures, between 6.86 and 335.11 K, the heat capacity of the synthesized material—pure, free of impurities and foreign phases—was determined by adiabatic calorimetry. In the range 315.3–965.3 K, Cp was determined by differential scanning calorimetry. The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. In the range 10–965 K, we have evaluated the standard thermodynamic functions: heat capacity, entropy, enthalpy increment, and reduced Gibbs energy. At 298.15 K, we have obtained = 72.43 ± 0.14 J/(K mol), S° = 94.94 ± 0.19 J/(K mol), Н°(298.15 K) − Н°(0) = 14.60 ± 0.03 kJ/mol, and Ф° = 45.97 ± 0.09 J/(K mol). Using the absolute entropy determined by us and data in the literature and handbooks, we have estimated the standard Gibbs energy of formation of RuTe2: ΔfG°(RuTe2, cr, 298.15) = −130.5 ± 2.9 kJ/mol. [ABSTRACT FROM AUTHOR]

To reveal the structure of tunnel-luminescence centres in AgBr(I) emulsion microcrystals (EMCs), we perform spectro-sensitometric and kinetic studies of their low-temperature (T = 77 K) luminescence. The luminescence characteristics depending on the binder, the presence and the nature of sensitizing additions (dyes) and the oxygen treatment are studied quantitatively. Special attention is paid to the comparative studies of the Stokes and dye-induced anti-Stokes luminescence components in the AgBr(I) EMCs. When the dye-sensitized AgBr(I) EMCs distributed in the polyvinyl alcohol are excited by the light photons with the energies corresponding to the intrinsic absorption region of the EMCs (λmax ≈ 460 nm), the kinetics of the luminescence band centred at the wavelength λmax ≈ 560 nm is monotonic. On the contrary, upon excitation by the photons corresponding to the absorption region of a J-aggregated dye (λmax ≈ 680 nm), the kinetics of the anti-Stokes glow (λmax ≈ 560 nm) is characterized by a rapid 'flash' followed by a gradual decrease to a stationary level (a 'flash enhancement'). These results indicate that a non-equilibrium transfer of charge carriers from the dye, which is adsorbed on the EMC surface, to the EMC volume depends essentially on the binder. If gelatine is the binder, this process is significantly affected by the oxygen adsorption, whereas the resulting effect depends on the aggregate form of the adsorbed dye. Understanding of physicochemical processes that govern the luminescence centres should enable one to control the structural transformations of the donor-acceptor complexes and clusters, which are responsible for the unique photometric properties of AgBr(I), and optimize their parameters for various applications in optoelectronics, holography, photographic materials science, optical sensors and solar energy systems. [ABSTRACT FROM AUTHOR]

In modern science, immortalized cells are not only a convenient tool in fundamental research, but they are also increasingly used in practical medicine. This happens due to their advantages compared to the primary cells, such as the possibility to produce larger amounts of cells and to use them for longer periods of time, the convenience of genetic modification, the absence of donor-to-donor variability when comparing the results of different experiments, etc. On the other hand, immortalization comes with drawbacks: possibilities of malignant transformation and/or major phenotype change due to genetic modification itself or upon long-term cultivation appear. At first glance, such issues are huge hurdles in the way of immortalized cells translation into medicine. However, there are certain ways to overcome such barriers that we describe in this review. We determined four major areas of usage of immortalized cells for practical medicinal purposes, and each has its own means to negate the drawbacks associated with immortalization. Moreover, here we describe specific fields of application of immortalized cells in which these problems are of much lesser concern, for example, in some cases where the possibility of malignant growth is not there at all. In general, we can conclude that immortalized cells have their niches in certain areas of practical medicine where they can successfully compete with other therapeutic approaches, and more preclinical and clinical trials with them should be expected. [ABSTRACT FROM AUTHOR]

This review presents a strategy for obtaining various functional derivatives of tetrapyrrole compounds based on transformations of unsaturated carbon-oxygen and carbon-carbon bonds of the substituents at the meso position (meso-formyl, vinyl, and ethynyl porphyrins). First, synthetic approaches to the preparation of these precursors are described. Then diverse pathways for the transformations of the multipotent synthons are discussed, revealing a variety of products of such reactions. The structures, electronic, and optical properties of the compounds obtained by the methods under consideration are analyzed. In addition, there is an overview of the applications of the products obtained. Biomedical use of the compounds is among the most important. Finally, the advantages of using the reviewed synthetic strategy to obtain dyes with targeted properties are highlighted. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of crystalline platinum ditelluride, PtTe2, a synthetic analog of the mineral moncheite, and its thermodynamic properties. Using the isobaric heat capacity of PtTe2 determined in the range 2–305 K by the relaxation and adiabatic calorimetry methods, we have evaluated its standard thermodynamic functions: entropy, enthalpy increment, and reduced Gibbs energy. The following parameters have been obtained for PtTe2 at 298.15 K: = 75.11 ± 0.15 J/(K mol), S° = 121.5 ± 0.2 J/(K mol), Н°(298.15 K) − Н°(0) = 16.69 ± 0.03 kJ/mol, and Ф° = 65.55 ± 0.13 J/(K mol). Using data in the literature and handbooks, we have estimated the standard Gibbs energy of formation of PtTe2: ΔfG°(PtTe2, cr, 298.15) = –75.4 ± 0.8 kJ/mol. Fractal analysis of the heat capacity data indicates that PtTe2 has a layered structure and that its Debye temperature is 250 K. [ABSTRACT FROM AUTHOR]

In this work, to control the content of dichroic complexes in film polarizers based on polyvinyl alcohol, a luminescent technique is proposed that allows us to estimate: the ratio of molecular and paired iodine centers in H-type polarizers at T = 4.2 K; of dichroic complexes caused by molecular and aggregated forms of the dye in L-type polarizers at T = 300 K. The use of this technique will make it possible in the future to establish the dependence of the properties of polarizers on the structure of dichroic complexes, not only in H-type or L-type film polarizers but also in mixed (H + L)-type polarizers, to create polarizers of various spectral ranges. [ABSTRACT FROM AUTHOR]

A hydrogen-bonded CHF⋯HF complex was characterized by FTIR matrix isolation spectroscopy and ab initio calculations. Three possible structures of this complex were found at the coupled-cluster with single, double, and perturbative triple excitations [CCSD(T)/L3a_3] level of theory. The comparison between the experiment and theory reveals that the most stable structure with the binding energy of 6.48 kcal/mol is formed upon x-ray irradiation of isolated CH2F2 molecules in noble gas matrices (Ne, Ar, Xe). This species appears to be the first known intermolecular complex of monofluorocarbene, and its identification was unambiguously proved by IR absorptions corresponding to HF deformation (libration), CF stretching, H–C–F bending, and CH and HF stretching modes. It is worth noting that the corresponding spectral features in an argon matrix were previously tentatively ascribed to CH2F2+· and HF⋯CHF−· [L. Andrews and F. T. Prochaska, J. Chem. Phys. 70, 4714 (1979)], but the calculations performed in the present study definitely support the re-assignment. The observed CHF⋯HF complex can be converted to the parent CH2F2 under the action of light with λ < 525 nm. The plausible mechanism of this conversion using the conical intersection concept is discussed. [ABSTRACT FROM AUTHOR]

We introduce the notion of reflective ability and discuss its energy dependence using rational form of unitarization. Correspondence with the phase of exponential unitarization is traced. Increase of the reflective ability of interaction region starts at the LHC energies. Numerical estimates are given. [ABSTRACT FROM AUTHOR]

The article is devoted to the development of accurate theoretical methods for predicting the pressure of compression shells on the human body. A mathematical model based on numerical methods has been developed. The software script is available for embedding as a 3D-CAD module for designing compression clothing. [ABSTRACT FROM AUTHOR]

Parathyroid hormone (PTH) is one of the key regulators of calcium and phosphate metabolism in the body, controlling bone metabolism and ion excretion by the kidneys. At present, attempts to use PTH as a therapeutic agent have been associated with side-effects, the nature of which is not always clear and predictable. In addition, it is known that in vivo impairment of PTH post-receptor signaling is associated with atypical differentiation behavior not only of bone cells, but also of connective tissues, including adipose tissue. In this work, we studied the functional responses of multipotent mesenchymal stromal cells (MSCs) to the action of PTH at the level of single cells. We used MSCs isolated from the periosteum and subcutaneous adipose tissue to compare characteristics of cell responses to PTH. We found that the hormone can activate three key responses via its receptor located on the surface of MSCs: single transients of calcium, calcium oscillations, and hormone-activated smooth increase in intracellular calcium. These types of calcium responses led to principally different cellular responses of MSCs. The cAMP-dependent smooth increase of intracellular calcium was associated with pro-osteogenic action of PTH, whereas phospholipase C dependent calcium oscillations led to a decrease in osteogenic differentiation intensity. Different variants of calcium responses are in dynamic equilibrium. Suppression of one type of response leads to increased activation of another type and, accordingly, to a change in the effect of PTH on cell differentiation. [ABSTRACT FROM AUTHOR]

The problem of insufficient accuracy, informativeness and efficiency of recognition of the structure and composition of inhomogeneous surface layers of thin metal-oxide heterostructures during nondestructive testing by spectral optical methods is considered. It is noted that the currently available methods of studying such layers, as a rule, are destructive in nature. To improve the accuracy, informativeness and efficiency of nondestructive testing of the chemical composition of thin metal-oxide heterostructures, a method of phase-spectral ellipsometry has been developed. In this method, the results of ellipsometric measurements of reflected radiation of various wavelengths are used to determine the distribution function of the complex refractive index of an inhomogeneous surface layer along its depth. To implement the proposed method, a phase spectral ellipsometer circuit with a wavelength as a control signal of the feedback channel has been created. The method of phase-spectral ellipsometry is used to control the distribution of chemical composition over the depth of thin metal-oxide heterostructures on the surface of stainless steel Cr18–Ni10–Ti, oxidized at low temperatures and oxygen pressures. When comparing the obtained results with independent Auger profiling data of oxidized samples, it was found that the distribution of the chemical composition over the depth of the oxide corresponds to the independent Auger data. It is shown that the method of phase-spectral ellipsometry makes it possible to clearly separate and identify various oxidized forms of the alloy. The presented method can be used for nondestructive and especially in-situ study of the distribution of chemical composition over the depth of ultrathin inhomogeneous surface oxides. [ABSTRACT FROM AUTHOR]

We consider two possible options of the energy dependency of the elastic and inelastic overlap functions. Those correspond to saturation of the black disk limit (BEL effect) and to the unitarity saturation (REL effect) at s â†' ∞. Relation of the REL effect to increase of the ratio σ el(s)/ σ tot(s) and emergence of black ring picture at the LHC is underlined. [ABSTRACT FROM AUTHOR]

The project of a pulsed spallation neutron source driven by a 1.32-GeV proton beam accelerated in the existing rapid cycling proton synchrotron U-1.5 at the National Research Centre "Kurchatov Institute" (NRC KI)–Institute for High Energy Physics (IHEP) is presented. This option would constitute a short-term cost-effective diversification of applied research capabilities of the U-1.5 machine (orbit length 99 m), the facility otherwise employed as a ring injector (booster) into the subsequent larger proton synchrotron U-70 (1.487 km). The source will be used primarily for neutron time-of-flight research techniques. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) is a multifactorial bone disease belonging to the metabolic osteopathies group. Using the polygenic score (PGS) approach, we combined the effects of bone mineral density (BMD) DNA loci, affecting osteoporosis pathogenesis, based on GEFOS/GENOMOS consortium GWAS meta-analysis. We developed models to predict the risk of low fractures in women from the Volga-Ural region of Russia with efficacy of 74% (AUC = 0.740; OR (95% CI) = 2.9 (2.353–3.536)), as well as the formation of low BMD with efficacy of 79% (AUC = 0.790; OR (95% CI) = 3.94 (2.993–5.337)). In addition, we propose a model that predicts fracture risk and low BMD in a comorbid condition with 85% accuracy (AUC = 0.850; OR (95% CI) = 6.6 (4.411–10.608)) in postmenopausal women. [ABSTRACT FROM AUTHOR]

Simple Summary: The surface lipids of insects protect them from desiccation and may modulate susceptibility to fungal infections. We conducted a comparative analysis of cuticular lipids of the migratory locust and Italian locust. The former inhabits relatively wet landscapes and the latter more arid ones. We analyzed cuticular lipids of these species by gas chromatography with mass spectrometry and found that the Italian locust has a hydrocarbon profile shifted toward long chains as well as a higher content of di- and trimethyl branched hydrocarbons, which is most likely an adaptation to the arid climate and strong temperature fluctuations in its habitats. Meanwhile, the surface of the Italian locust proved to be more hospitable for fungi. The number of Metarhizium conidia attached to the Italian locust cuticle was three-fold greater as compared to the migratory locust. Mortality due to the fungal infection was faster in the Italian locust under laboratory conditions. We propose that species inhabiting arid landscapes rarely encounter fungal pathogens and primarily deal with the problem of desiccation. Therefore, they can afford a cuticle that is hospitable to fungal pathogens. Cuticular lipids protect insects from desiccation and may determine resistance to fungal pathogens. Nonetheless, the trade-off between these lipid functions is still poorly understood. The migratory locust Locusta migratoria and the Italian locust Calliptamus italicus have dissimilar hygrothermal preferences: L. migratoria inhabits areas near water bodies with a reed bed, and C. italicus exploits a wide range of habitats and prefers steppes and semideserts with the predominance of sagebrushes. This paper presents significant differences between these species' nymphs in epicuticular lipid composition (according to gas chromatography with mass spectrometry) and in susceptibility to Metarhizium robertsii and Beauveria bassiana. The main differences in lipid composition are shifts to longer chain and branched hydrocarbons (di- and trimethylalkanes) in C. italicus compared to L. migratoria. C. italicus also has a slightly higher n-alkane content. Fatty acids showed low concentrations in the extracts, and L. migratoria has a wider range of fatty acids than C. italicus does. Susceptibility to M. robertsii and the number of conidia adhering to the cuticle proved to be significantly higher in C. italicus, although conidia germination percentages on epicuticular extracts did not differ between the species. We propose that the hydrocarbon composition of C. italicus may be an adaptation to a wide range of habitats including arid ones but may make the C. italicus cuticle more hospitable for fungi. [ABSTRACT FROM AUTHOR]

Background: For the needs of modern biotechnology, a quantitative approach to the control of regulatory elements at all stages of gene expression has long become indispensable. Such a control regime is impossible without a quantitative analysis of the role of each regulatory element or pattern used. Therefore, it seems important to modify and develop the accuracy, reproducibility, and availability of methods for quantifying the contribution of each regulatory code to the implementation of genetic information. Results: A new vector system for transient expression in plants is described; this system is intended for quantitative analysis of the contribution of regulatory elements to transcription and translation efficiencies. The proposed vector comprises two expression cassettes carrying reporter genes (of the Clostridium thermocellum thermostable lichenase and E. coliβ-glucuronidase) under the control of different promoters. Herewith we also propose a new method for quantification of the effect of tested regulatory elements on expression, which relies on assessment of the enzyme activities of reporter proteins taking into account the transcription of their genes. Conclusions: In our view, this approach makes it possible to precisely determine the amounts of reporter proteins and their transcripts at all stages of expression. The efficiency of the proposed system has been validated by the analysis of the roles of known translation enhancers at the stages of transcription and translation. [ABSTRACT FROM AUTHOR]

We provide arguments for the use of the rational form of unitarization, its relation with the diffraction peak shrinkage and asymptotics of the inelastic cross-section. The particular problems of the Regge model and the exponential form of unitarization with a factorized eikonal are discussed as well. A central role belongs to the asymptotic amplitude factorization resulting from Mandelstam analyticity and its symmetry over the scattering variables. [ABSTRACT FROM AUTHOR]

We report on the preparation and vibrational characterization of the C2H3...CO2 complex, the first example of a stable intermolecular complex involving vinyl radicals. This complex was prepared in Ar and Kr matrices using UV photolysis of propiolic acid (HC3OOH) and subsequent thermal mobilization of H atoms. This preparation procedure provides vinyl radicals formed exclusively as a complex with CO2, without the presence of either CO2 or C2H3 monomers. The absorption bands corresponding to the v5(C2H3), v7(C2H3), v8(C2H3), v2(CO2), and v3(CO2) modes of the C2H3...CO2 complex were detected experimentally. The calculations at the UCCSD(T)/L2a level of theory predict two structures of the C2H3...CO2 complex with Cs and C1 symmetries and interaction energies of -1.92 and -5.19 kJ mol-1. The harmonic vibrational frequencies of these structures were calculated at the same level of theory. The structural assignment of the experimental species is not straightforward because of rather small complexation-induced shifts and matrix-site splitting of the bands (for both complex and monomers). We conclude that the C1 structure is the most probable candidate for the experimental C2H3...CO2 complex based on the significant splitting of the bending vibration of CO2 and on the energetic and structural considerations. [ABSTRACT FROM AUTHOR]

The structure and properties of steel 30KhGSA are studied after hardening by the quenching and partitioning (Q&P) process and, for comparison, by the standard modes of quenching and tempering. Metallographic and fractographic analyses and impact bending tests of the steel are performed. Kinetic diagrams of fatigue fracture are plotted, and the stress intensity factor ∆K and the rate of growth of fatigue crack v are computed. It is shown that the Q&P treatment yields a heterogeneous martensitic structure with interlayers of ductile retained austenite, which raises the impact toughness of the steel by a factor of 1.5 – 2 and the resistance to fatigue crack propagation by a factor of 1.5 as compared to the same characteristics after the traditional quenching and tempering. The strength of the steel remains virtually unchanged. The Q&P treatment may be recommended for raising the structural strength of heavily loaded machine parts. [ABSTRACT FROM AUTHOR]

Spectroscopic characteristics and X-ray induced transformations of the HCN... CO2 complex in solid Ar and Kr matrices were studied by FTIR spectroscopy and ab initio calculations at the CCSD(T) level. The complexwas prepared by deposition of the HCN/CO2/Ng gas mixtures (Ng = Ar or Kr). The comparison of the experiment and calculations prove formation of a linear, H-bonded NCH... OCO complex with a substantial red shift of the C-H stretching band and a blue shift of the H-C-N bending band in respect to the monomer. This result is in contrast with the previous gas-phase observations, where only T-shape complex was found. Irradiation of deposited matrices leads to formation of CN radicals and HNC molecules and subsequent annealing results in appearance of H2CN and trans-HCNH in both matrices plus HKrCN in the case of Kr. In the presence of CO2, the strongest absorption of trans-HCNH radical demonstrates an additional blue-shifted (by 6.4 cm-1) feature, which was assigned to the N-coordinated complex of this radical with CO2 on the basis of comparison with calculations. To our knowledge, it is the first experimentally observed complex of this radical. No evidence was found for HKrCN... CO2 complex, which was explained tentatively by steric hindrance. [ABSTRACT FROM AUTHOR]

The radiation-induced transformations of isolated dimethyl disulphide molecules in a solid argon matrix occurring under the action of X-rays at 4.5 K were studied by FTIR spectroscopy. It was shown that decomposition was quite efficient (the corresponding radiation-chemical yield of Me 2 S 2 degradation was estimated as 4.5 molecules per 100 eV). The radiolysis proceeds via two primary channels yielding CH 3 SH plus H 2 CS and CH 4 plus H 2 CSS, respectively. These two channels of dimethyl disulphide decay during radiolysis lead to various secondary products appearing during prolonged radiolysis. Spectroscopic characteristics of the observed products and possible implications of the results are discussed. • Efficient radiolysis of isolated dimethyl disulphide molecules in solid argon was showed. • Two primary channels of radiolysis of dimethyl disulphide molecules were discovered. • With prolonged radiolysis of dimethyl disuphide molecules, a variety set of products is discovered. [ABSTRACT FROM AUTHOR]

The thermophysical characteristics of nonmetallic materials (in particular, thermal conductivity and thermal diff usivity) account for their heat-insulating properties, the quality of processing in various laser technologies, and also signifi cantly aff ect the optical strength of power optics materials. Determination of thermophysical characteristics by traditional methods requires laborious manufacturing of specimens of certain sizes and two-sided access to them, which prevents the use of nondestructive testing of large workpieces and fi nished products. The article describes a nondestructive thermographic method of measuring the thermal diff usivity of transparent and semitransparent materials, which does not require cutting out samples from the test object and two-sided access to it. To increase the coeffi cients of absorption and emission of visible and infrared radiation of the accessible surface, thin opaque coatings or targets with a diameter of several tenths of a millimeter were used. The method was tested on eight optically transparent polymeric, amorphous, and crystalline materials diff ering in composition, spectral characteristics of light absorption, surface condition and overlapping about 2 orders of magnitude in thermal diff usivity. The described procedure demonstrated a small random error (0.5% for polymethyl methacrylate, 1.1% for polycarbonate, 2.3% for fused quartz, 3.3% for monocryslalline NaCl) at a speed of about 10 s, which makes it possible to use it for rapid diagnostics of newly created heat-shielding materials and elements of power optics. [ABSTRACT FROM AUTHOR]

In this paper, we propose a general algorithmic framework for the first-order methods in optimization in a broad sense, including minimization problems, saddle-point problems and variational inequalities (VIs). This framework allows obtaining many known methods as a special case, the list including accelerated gradient method, composite optimization methods, level-set methods, Bregman proximal methods. The idea of the framework is based on constructing an inexact model of the main problem component, i.e. objective function in optimization or operator in VIs. Besides reproducing known results, our framework allows constructing new methods, which we illustrate by constructing a universal conditional gradient method and a universal method for VIs with a composite structure. This method works for smooth and non-smooth problems with optimal complexity without a priori knowledge of the problem's smoothness. As a particular case of our general framework, we introduce relative smoothness for operators and propose an algorithm for VIs with such operators. We also generalize our framework for relatively strongly convex objectives and strongly monotone VIs. [ABSTRACT FROM AUTHOR]

Background: Since the beginning of the use of reporter proteins for expression analysis, a variety of approaches have been developed and proposed; both qualitative and quantitative. The lack of simple methods for direct observation of gene expression in living organisms makes it necessary to continue to propose new methods. In this work, we consider a method for the quantitative analysis of the expression of thermostable lichenase from Clostridium thermocellum used as a sensitive reporter protein. Results: In this study, we report the design a high throughput fluorometric method for quantification of thermostable lichenase C. thermocellum using Congo red and further experimental verification of its relevance and efficiency in assessment of the functional role of regulatory sequences in the plant cell. Conclusions: The specific interaction between the dye Congo red and β -d-glucans formed the background for designing a high-throughput fluorometric assay for quantification of C. thermocellum thermostable lichenase as a reporter protein for plants. This assay (i) makes it possible to precisely measure the amount of reporter protein in a plant sample; (ii) has shown a high sensitivity for quantification of thermostable lichenase; (iii) is more time- and cost-efficient as compared with the Somogyi–Nelson assay; and (iv) is to the least degree dependent on the presence of the tested buffer components as compared with the Somogyi–Nelson assay. [ABSTRACT FROM AUTHOR]

We report a novel family of natural lipoglycopeptides produced by Streptomyces sp. INA‐Ac‐5812. Two major components of the mixture, named gausemycins A and B, were isolated, and their structures were elucidated. The compounds are cyclic peptides with a unique peptide core and several remarkable structural features, including unusual positions of d‐amino acids, lack of the Ca2+‐binding Asp‐X‐Asp‐Gly (DXDG) motif, tyrosine glycosylation with arabinose, presence of 2‐amino‐4‐hydroxy‐4‐phenylbutyric acid (Ahpb) and chlorinated kynurenine (ClKyn), and N‐acylation of the ornithine side chain. Gausemycins have pronounced activity against Gram‐positive bacteria. Mechanistic studies highlight significant differences compared to known glyco‐ and lipopeptides. Gausemycins exhibit only slight Ca2+‐dependence of activity and induce no pore formation at low concentrations. Moreover, there is no detectable accumulation of cell wall biosynthesis precursors under treatment with gausemycins. [ABSTRACT FROM AUTHOR]

We report a novel family of natural lipoglycopeptides produced by Streptomyces sp. INA‐Ac‐5812. Two major components of the mixture, named gausemycins A and B, were isolated, and their structures were elucidated. The compounds are cyclic peptides with a unique peptide core and several remarkable structural features, including unusual positions of d‐amino acids, lack of the Ca2+‐binding Asp‐X‐Asp‐Gly (DXDG) motif, tyrosine glycosylation with arabinose, presence of 2‐amino‐4‐hydroxy‐4‐phenylbutyric acid (Ahpb) and chlorinated kynurenine (ClKyn), and N‐acylation of the ornithine side chain. Gausemycins have pronounced activity against Gram‐positive bacteria. Mechanistic studies highlight significant differences compared to known glyco‐ and lipopeptides. Gausemycins exhibit only slight Ca2+‐dependence of activity and induce no pore formation at low concentrations. Moreover, there is no detectable accumulation of cell wall biosynthesis precursors under treatment with gausemycins. [ABSTRACT FROM AUTHOR]

New the experimental results of thermally stimulated hydrogen release (TCHR) from plane-parallel plates of Ti, Zr, Ni, Pd, Pt metals with various thicknesses (0.05–1 mm), pre-saturated with hydrogen, under linear heating (1 °C s−1) presented. The electrolytic and Sieverts method for saturate were used. Theoretical models for diffusion and desorption hydrogen release from flat metal samples into vacuum with linear heating were developed. In this case, the processes of diffusion and thermal desorption were taken into account to select the optimal conditions and experimental methods. The TSHR spectra simulated using the MATLAB software package to test the consistency of theory with experiment. By modeling in MATLAB using both the developed models and experimental TSHR spectra, the activation energies of desorption, diffusion and decomposition of hydrides, as well as the preexponential factors in the diffusion and kinetic equations, were determined. • Studied thermal stimulated hydrogen release (TSHR) from different metals allows. • Studied and performed mathematical analysis of hydrogen desorption kinetics. • Developed physical and mathematical models of TSHR. • Simulated hydrogen diffusion, desorption, hydride decay processes with MATLAB. • Determined activation diffusion, desorption and decomposition energy and others. [ABSTRACT FROM AUTHOR]

Providing some examples of Lagrangian cycles that arise as a generalization of Mironov's construction to the case of Grassmann manifolds , we show that these manifolds enjoy all data necessary for this generalization, the natural real structure, and an incomplete toric action. We also provide new concrete examples. [ABSTRACT FROM AUTHOR]

This study reports the first general, practical, and facile synthesis of phosphorus-substituted 1,3,4-thiadiazolines starting from phosphorylthioformic acid hydrazides and ketones. Various cyclic ketones were efficiently incorporated into spiro 1,3,4-thiadiazoline derivatives by a two-step sequence involving the heterocyclization with phosphorylthioformic acid hydrazides followed by the nitrogen acylation with acyl chlorides. The protocol is characterized by operational simplicity, readily available reagents, and functional group tolerance. [Display omitted] [ABSTRACT FROM AUTHOR]

The efficiency of heat transfer in heat exchangers having a staggered and in-line arrangement of a tube bundle is compared. The dependence of pressure losses on the minimum relative tube pitch for the considered arrangements of tubes at various Reynolds numbers is shown. Using heat exchangers with staggered tube arrangements at production facilities for chemical fibers is substantiated. [ABSTRACT FROM AUTHOR]

The relationship between the mechanical properties of anisotropic materials and their thermophysical characteristics was experimentally revealed using the example of Scots pine (Pınus sylvéstris L) wood. By measuring the hardness and principal components of the thermal diffusivity tensor, on three sections (normal to the fibers, tangential, and radial) at different wood moisture content, it has been shown that this relationship can be described by linear functions. This makes it possible to carry out an express assessment of the mechanical properties of anisotropic materials, which normally require labor- and material-intensive destructive tests, by means of contactless nondestructive determination of their thermophysical characteristics using the method of dynamic thermography. [ABSTRACT FROM AUTHOR]

We have for the first time determined the temperature dependence of heat capacity for aurostibite, AuSb2, by adiabatic calorimetry and calculated its standard thermodynamic functions in a wide temperature range. At a temperature of 298.15 K, we have obtained = 76.01 ± 0.15 J/(mol K), S° = 133.4 ± 0.3 J/(mol K), Н°(298.15 K) − Н°(0)= 17.39 ± 0.03 kJ/mol, and Ф° = 75.02 ± 0.15 J/(mol K). Using previously reported data and the present results, we have found ΔfG°(298.15) = −11.36 ± 0.90 kJ/mol. [ABSTRACT FROM AUTHOR]

The recently identified ferroptotic cell death is characterized by excessive accumulation of hydroperoxy-arachidonoyl (C20:4)- or adrenoyl (C22:4)- phosphatidylethanolamine (Hp-PE). The seleniumdependent glutathione peroxidase 4 (GPX4) inhibits ferroptosis, converting unstable ferroptotic lipid hydroperoxides to nontoxic lipid alcohols in a tissue-specificmanner. While placental oxidative stress and lipotoxicity are hallmarks of placental dysfunction, the possible role of ferroptosis in placental dysfunction is largely unknown. We found that spontaneous preterm birth is associated with ferroptosis and that inhibition of GPX4 causes ferroptotic injury in primary human trophoblasts and during mouse pregnancy. Importantly, we uncovered a role for the phospholipase PLA2G6 (PNPLA9, iPLA2beta), known to metabolize Hp-PE to lyso-PE and oxidized fatty acid, in mitigating ferroptosis induced by GPX4 inhibition in vitro or by hypoxia/ reoxygenation injury in vivo. Together, we identified ferroptosis signaling in the human and mouse placenta, established a role for PLA2G6 in attenuating trophoblastic ferroptosis, and provided mechanistic insights into the ill-defined placental lipotoxicity that may inspire PLA2G6-targeted therapeutic strategies. [ABSTRACT FROM AUTHOR]

A new method for deriving estimates of the rate of convergence of optimal methods for solving problems of smooth (strongly) convex stochastic optimization is described. The method is based on the results of stochastic optimization derived from results on the convergence of optimal methods under the conditions of inexact gradients with small noises of nonrandom nature. In contrast to earlier results, all estimates in the present paper are obtained in model generality. [ABSTRACT FROM AUTHOR]

We suggest definition of effective interaction intensity for soft hadron collisions and discuss its energy dependence in the preasymptotic region. Practical importance of this quantity consists in separation of rising interaction radius from effective interaction intensity increase both contributing to the total cross-section growth. It would be helpful for understanding the origin of this growth at the accelerator energies. The essential feature is that the effective interaction intensity is an experimentally measurable quantity. [ABSTRACT FROM AUTHOR]

It has been previously found that, in the AgBr(I) emulsion microcrystals (with a silver content corresponding to pBr 4), the centers responsible for tunnel recombination at T = 77 K with a luminescence maximum at λmax ≈ 560 nm when excited by light from the absorption region of the AgBr(I) emulsion microcrystal (λ ≈ 450 nm) as a result of temperature "quenching" are subject to structural transformation into the centers that, under the same excitation, provide the tunnel recombination with a wavelength depending on a binder: λmax ≈ 720 nm for the AgBr(I) emulsion microcrystals obtained in water and λmax ≈ 750 nm for those obtained in gelatin. In this work, similar structural transformations of the centers that determine the tunnel recombination at λmax ≈ 560 nm to the centers with a glow at λmax ≈ 720 nm are implemented for the AgBr(I) emulsion microcrystals synthesized in polyvinyl alcohol at an increase in the content of silver ions in the emulsion from pBr 4 to pBr 7. The mobile interstitial silver ions Ag are responsible for this transformation, as follows from the results obtained. The effect of the binder on the recombination processes in the AgBr(I) emulsion microcrystals is manifested in changes in the kinetics of the increase in luminescence from λmax ≈ 560 nm when light is excited from the absorption region of the AgBr(I) emulsion microcrystal (λ ≈ 450 nm) to a stationary level. The increase in luminescence at λmax ≈ 560 nm occurs monotonously from zero to the maximum stationary level at the binder whose molecules do not interact with the centers Ag , n = 1, 2 (water, polyvinyl alcohol at pBr 4). The kinetics of the increase in luminescence in the AgBr (I) emulsion microcrystals to a stationary level at λ ≈ 560 nm and pBr 4 is characterized by the presence of "flash enhancement" at a binder (in our case, gelatin (G)) whose molecules form the (Ag G+) complexes with the Ag (n = 1, 2) centers. The adsorption on the AgBr(I) emulsion microcrystal (polyvinyl alcohol) surface of the dye is manifested as follows: if the kinetics of increase in luminescence at λmax ≈ 560 nm when excited by light from the region of the AgBr(I) emulsion microcrystal absorption (λ ≈ 450 nm) to the stationary level demonstrates "flash enhancement" prior to the introduction of dye, then, after the introduction of dye, the increase in luminescence at λmax ≈ 560 nm occurs monotonically from zero to a maximum fixed level. Studies of the "flash" of the luminescence stimulated by infrared (IR) radiation have shown that, after the termination of the exciting light when the kinetics of the increase in luminescence from λmax ≈ 560 nm to a stationary level demonstrates "flash enhancement", the "flash" stimulated by IR radiation is not observed at λ ≈ 560 nm. In the absence of "flash enhancement", a "flash" at λ ≈ 560 nm is observed. The results obtained, from our point of view, indicate that "flash enhancement" is due to the presence of deep centers of the localization of the electrons with a small capture cross-section and not to a photochemical reaction stimulated by the exciting light. [ABSTRACT FROM AUTHOR]

The interaction of neutral gas particles of thermal energies (molecules and atoms) with the surface of a solid is accompanied by radiation in the visible and I.R. parts of the spectrum. In this case, the surface of a solid body acts as a catalyst for the recombination reactions of gas particles. In this connection, the possibility of exciting luminescence during the catalytic oxidation of carbon monoxide directly by the atomic form of oxygen pre-adsorbed on the surface of a solid is of interest. Kinetic and spectral methods were used to study the luminescence arising from the catalytic oxidation of carbon monoxide by the atomic form of oxygen preadsorbed on the surface of a solid - a sample of α-willemite Zn2SiO4:Mn2+. The main stages in the mechanisms of recombination between adsorbate particles are established. Electronic transitions in adsorption complexes and the activator ion have been identified. During the filling process, the sample temperature was maintained by a constant high-speed electronic control system of the heater current. This made it possible to avoid thermal side effects. The main stages in the mechanisms of recombination between adsorbate particles are established. Electronic transitions in adsorption complexes and the activator ion have been identified. It was found that luminescence excitation proceeds in two main stages, somewhat time-shifted. The two-stage mechanism for the catalytic oxidation of carbon monoxide on the surface of α-willemite with pre-adsorbed atomic oxygen allows a consistent description of the luminescence observed in this case. This type of luminescence has the prospect of using for studying the mechanisms of catalytic oxidation of carbon monoxide. [ABSTRACT FROM AUTHOR]

The temperature-dependent heat capacity of vysotskite, PdS, has been determined for the first time by adiabatic, relaxation, and differential scanning calorimetry in a wide temperature range and standard thermodynamic functions of PdS have been calculated. The 298.15-K values thus obtained are = 43.65 ± 0.09 J/(mol K), S° = 51.98 ± 0.10 J/(mol K), Н°(298.15 К) − Н°(0) = 8.03 ± 0.02 kJ/mol, and Ф° = 25.03 ± 0.05 J/(mol K). Using the present results and data in the literature, we obtained ΔfH°(PdS, 298.15 K) = –74.0 ± 1.0 kJ/mol and ΔfG°(PdS, 298.15 K) = –68.7 ± 1.0 kJ/mol. [ABSTRACT FROM AUTHOR]

A fast adaptive heuristic stochastic gradient descent method is proposed. It is shown that this algorithm has a higher convergence rate in practical problems than currently popular optimization methods. Furthermore, a justification of this method is given, and difficulties that prevent obtaining optimal estimates for the proposed algorithm are described. [ABSTRACT FROM AUTHOR]

Gadolinium hafnate samples were obtained by co-precipitation and precursor annealing at a temperature of ~1773 K and characterised by X-ray powder diffraction, scanning electron microscopy and chemical analysis. The molar heat capacity of Gd 2 Hf 2 O 7 ceramics with a pyrochlore structure was measured by adiabatic (8–340 K) and differential scanning calorimetry (315–1345 K). The heat capacity of gadolinium hafnate was extrapolated to 0 K without taking into account anomalies in the temperature range below 20 K. Standard thermodynamic functions were calculated based on the smoothed values of molar heat capacity: entropy, enthalpy change and reduced Gibbs energy. Using the high-temperature X-ray diffraction method, the temperature dependence of the Gd 2 Hf 2 O 7 cubic crystal lattice parameter was determined in the range of 298–1273 K and coefficients of instantaneous (α i), relative (α r) and linear thermal expansion (TE) were calculated. [ABSTRACT FROM AUTHOR]

Methods of recording and automated processing of the results of phase-modulated speckle interferometry of optically dense (opaque to intrinsic radiation) flames containing a condensed phase are described. The use of a high-speed single-frame measurement technique and special processing procedures made it possible to determine the spatiotemporal distribution of the refractive index, based on which the flame structure can be identified. As an example, the results of a study of the burning torch of a stationary droplet of medical paraffin are presented. [ABSTRACT FROM AUTHOR]

The results of studying the interaction H atoms with ZnS–Tm3+ surface using the phenomena of heterogeneous chemiluminescence (HCL) are presented. HCL is luminescence excited in the strongly exothermic interaction acts of hydrogen atoms on the surface. The kinetic and nonstationary characteristics of luminescence are studied in depending on the excitation conditions, which serve as light indicators of physicochemical processes, occurring on the surface. The interaction parameters of hydrogen atoms with the surface of zinc sulphide: cross-sections, frequency factors, activation energies based on kinetic and non-stationary characteristics of HCL are determined. • Features of the heterogeneous luminescence spectra in the first atomic layer. • Direct energy conversion into radiation at the hydrogen interaction with phosphor. • Non-stationary luminescent methods for studying of the atoms–surface interaction. • A theoretical model for explaining the experimental regularities developed. [ABSTRACT FROM AUTHOR]

The scheme, design, and hardware of a new laboratory apparatus for studying the interaction of beams of free atoms and molecules with the surfaces of phosphors are described. Methods for measuring the efficiency of electronic radiative processes on surfaces for studying the mechanisms of energy transfer and surface changes based on the spectral–kinetic characteristics of heterogeneous chemiluminescence are presented. Luminescent methods for studying the heterogeneous recombination of hydrogen atoms on the surfaces of solids allow one to explicitly select the impact (Rideal–Eley) and diffusion (Langmuir–Hinshelwood) recombination mechanisms and estimate the fraction of contributions of these mechanisms to the total recombination rate of atoms depending on the flow density of free atoms and the sample temperature. Examples of studying the spectra of the heterogeneous chemiluminescence (HCL) and photoluminescence (PL) at different temperatures of an AlN : Eu3+ phosphor under the excitation with hydrogen atoms and a mercury lamp are given. During processing of the kinetic curves of the HCL buildup and decay for ZnS : Tm3+ phosphor upon switching the Н + Н2 atomic–molecular beam on and off, an example of obtaining the parameters of atomic–molecular processes on the surface (adsorption, impact and diffusion recombination of atoms, and desorption of hydrogen molecules) is presented. [ABSTRACT FROM AUTHOR]