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Experimental data on the passing of signals from navigation satellites of the L1 range through forest plantations with an anisotropic horizontal tree arrangement structure are presented. A feature of the studied environment is an irregular distance between trees in rows and a constant distance between rows. Signals were recorded by an antenna located inside the forest at heights of 0.5 and 10 meters. Based on the results of processing the amplitude-time dependences of the recorded signal by means of fast Fourier transform, qualitative differences were revealed depending on the orientation of the probe signal path in the forest stand.

An obvious connection of legal culture, value orientations and legal consciousness was established by cross-disciplinary analysis. Legal culture is considered as a whole in relation to legal value orientations. The necessity of forming legal value orientations is proved, as without them it is impossible to achieve a high level of legal culture and to ensure a student’s behavior within the framework of the law. This component is analyzed as a compulsory element of a law school student’s legal consciousness. The concept of legal value orientations is defined from the standpoint of different approaches and from the point of view of various authors, wherein these orientations are studied through the cognitive-volitional component. The relation of legal value orientations and legal beliefs is analyzed. It is offered to comply with a number of pedagogical conditions, to apply certain methods and techniques, which will influence the educational process and will promote forming legal value orientations. The need for developing value orientations in students is proved; it is shown that without value orientations it is impossible to reach a high level of legal culture, to engage in civic activities and to become a law-abiding citizen. Legal value orientations are studied as a construction material of legal culture and govern a student’s legal behavior.

Energy saving potential is quite huge in the most sectors of the national economy, particularly in housing and utilities and industry. Due to this, energy efficiency increase at the enterprises of housing and utilities and industry through the energy efficiency programs implementation, is one of the priorities in the modern economy of Russia and its regions, and requires radical measures to improve the effectiveness of its implementation. The purpose of the authors is the scientific and practical study of the main problems of energy efficiency programs implementation at the enterprises of housing and utilities services and industry in modern conditions. To achieve this purpose the authors solved the following problems: the current state of the housing and utilities sector and industry, the relevance and the need for energy saving policy at the enterprises of housing and utilities services and industry are studied; the main problems impeding to implement the energy-saving program effectively at the enterprises of housing and utilities services and industry are determined; the possible ways of solving the problems identified in the energy efficiency programs implementation at the enterprises of housing and industry are offered. The team of authors focuses in this study on the problems of the energy audit using in practice as a basic tool for the energy saving programs development at the enterprises of housing and utilities services, industry and their subsequent implementation. The subject of author's researches is the factors that determine the energy efficiency programs implementation at the enterprises of housing and utilities services and industry at the level of individual region and the whole country, and the object is the enterprises of housing and utilities services and industry. Methodologically the scientific and practical research is based on the complex approach using the methods of comparative, statistical and logical analysis.

The 19th International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2016), held at the P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow (LPI RAS) from 22 to 28 August 2016, attracted more than 120 participants. The Symposium was carried out under the auspices of the International Union of Pure and Applied Physics (IUPAP) with financial support from the Federal Agency for Scientific Organizations and the Russian Foundation for Basic Research.

Russia is the one of the most wasteful countries in the world in using of fuel and energy resources. Energy-saving potential is huge enough. Thereby energy efficiency programs implementation at the enterprises of mechanical engineering is the one of priority tasks of modern economics of Russia and requires radical measures of increasing the efficiency of its implementation. The purpose of Author’s search is scientific and practical research of modern problems of energy efficiency programs implementation at the enterprises of mechanical engineering. In achieving of this purpose the following tasks were solved by authors: justified relevance and necessity of implementation of energy-saving policies at the enterprises of mechanical engineering in the regions of Russia; indentified the most significant problems preventing effective implementation of energy-saving program at the enterprises in the regions of Russia; proposed possible directions solving reveal problems in sphere of energy-saving programs implementation at the enterprises in the regions of Russia. In presented research Author’s collective focuses on problems of energy audit using in practice as the main instrument for working-out of energy-saving programs at the enterprises of mechanical engineering and the its subsequent implementation. The subject of Author’s research is the factors defining energy-saving implementation at the enterprises of mechanical engineering, the object is the enterprises of this one. Methodological scientific and practical research is based on a complex approach with using of methods of comparative, analytical and logical analysis.

In this study, we report the first example of acyclic (amino)(N-pyridinium)carbenoid gold(III) complexes synthesized via a coupling reaction between 2-pyridylselenyl chloride and Au(I)-bound isonitriles. The reaction involves an initial oxidative addition of the Se–Cl moiety to Au(I), followed by the nucleophilic addition of the pyridine fragment to the isonitrile's C≡N bond, furnishing a metallacycle. Importantly, this is the first example of the pyridine acting as a nucleophile towards metal-bound isonitriles. Arguably, such an addition is due to the chelate effect. The structures of the gold(III) carbenoid complexes were unambiguously established using X-ray diffraction and NMR spectroscopy. Theoretical calculations, including DFT, Natural Resonance Theory (NRT), and Meyer bond order (MBO) analyses, were used to analyze the different resonance forms. The reaction mechanism was further elucidated using DFT calculations, which identified the oxidative addition as the rate-determining step with a barrier of 29.7 kcal/mol. The nucleophilic addition proceeds with a minimal barrier, making the reaction highly favorable. The antiproliferative activity of new compounds 2a–2e was tested against two human cancer cell lines: A2780 ovarian adenocarcinoma and the A278Cis cisplatin-resistant variant. [ABSTRACT FROM AUTHOR]

The paper presents new results of manufacturing coatings by magnetron sputtering to improve the functional properties of joint endoprostheses. The antibacterial properties of Ti-Cu and Ta-Cu coatings deposited by DC multi-magnetron sputtering on Ti6Al4V alloy substrates subjected of gas-abrasive treatment have been investigated. The roughness of the substrate was measured by optical profilometry. The coating hardness and elastic modulus were estimated by nanoindentation methods; the adhesion characteristics were assessed by Rockwell test. Scanning electron microscopy with energy-dispersive X-ray analysis verified the application of coatings with 25 at.% Cu, at thicknesses of 2 μm and 10 μm to roughened Ti6Al4V alloy. All coatings demonstrated sufficient adhesion, whereas Ta-Cu coatings generally revealed higher hardness, while the elastic modulus decreased with increasing coating thickness. Staphylococcus aureus strains were used for in vitro study of the antibacterial properties of Ti-Cu and Ta-Cu coatings. The largest zones of inhibition of bacteria S. aureus 23 mm were observed for 10 µm Ta-Cu coating thickness. The release dynamics of Cu ions from Ta-Cu and Ti-Cu coatings into physiological solution analyzed over seven days via inductively coupled plasma mass spectrometry, matched the inhibition zone growth. The Ti-Cu and Ta-Cu coatings of 2 µm thickness provided weaker antibacterial effect. The optimal parameters of magnetron sputtering of antibacterial Ti-Cu and Ta-Cu coatings on Ti6Al4 alloy substrates were selected. These findings support the potential of these coatings in developing endoprosthesis implants with enhanced antimicrobial and wear-resistant properties [ABSTRACT FROM AUTHOR]

Herein, we describe a novel coupling between ambiphilic 2-pyridylselenyl reagents and nitriles featuring an active α-methylene group. Depending on the solvent employed, this reaction can yield two distinct types of cationic pyridinium-fused selenium-containing heterocycles, 1,3-selenazolium or 1,2,4-selenadiazolium salts, in high yields. This is in contrast to what we observed before for other nitriles. Notably, the formation of selenadiazolium is reversible, gradually converting into the more thermodynamically stable selenazolium product in solution. Our findings reveal, for the first time, the reversible nature of 1,3-dipolar cyclization between the CN triple bond and 2-pyridylselenyl reagents. Nitrile substitution experiments in the adducts confirmed the dynamic nature of this cyclization, indicating potential applications in dynamic covalent chemistry. DFT calculations revealed the mechanistic pathways for new cyclizations, suggesting a concerted [3 + 2] cycloaddition for the formation of selenadiazolium rings and a stepwise mechanism involving a ketenimine intermediate for the formation of selenazolium rings. Natural bond orbital analysis confirmed the involvement of σ-hole interactions and lone pair to σ* electron donation in these processes. Additionally, theoretical investigations of σ-hole interactions were performed, focusing on the selenium-centered contacts within the new compounds. [ABSTRACT FROM AUTHOR]

A new pyridine-fused selenodiazolium salt, 3-(phenylselanyl)[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride dichloromethane 0.352-solvate, C12H9-N2Se2+ ·Cl ·0.352CH2Cl2, was obtained from the reaction between 2-pyridylselenenyl chloride and phenylselenocyanate. Single-crystal structural analysis revealed the presence of C—H...N, C—H...Cl, C—H...Se hydrogen bonds as well as chalcogen–chalcogen (Se...Se) and chalcogen–halogen (Se...Cl ) interactions. Non-covalent interactions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of selenodiazolium moieties arranged in a head-to-tail fashion surrounding disordered dichloromethane molecules. The assemblies are connected by C—H...Cl and C—H...N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se...Cl- ...H—C interact [ABSTRACT FROM AUTHOR]

Preliminary ab initio calculations led to the synthesis of novel substituted thiazolium salts, analogs of Alagebrium, which were further explored in vitro for their potential as inhibitors of the glycation reaction utilizing three distinct assays: inhibition of fluorescent AGEs formation, anticrosslinking, and deglycation. Despite the unidirectionality of the assays, distinct differences were observed in the mechanisms of interference and activity manifestation by the compounds. The gathered data permitted the formation of hypotheses about the molecular fragments of the studied antiglycators that are of utmost significance in each assay, thereby guiding future design endeavors. Potential mechanisms of actions are discussed therein. The compound 4‐meth‐yl‐3‐[2‐(4‐methylbiphenyl‐4‐yl)‐2‐oxoethyl] thiazolium bromide displayed high activity across all three assays, establishing it as a lead compound. The cytotoxicological properties of the compounds were evaluated using LDH and MTT assays. However, the lead compound exhibited cytotoxicity, indicating the need for additional investigations aimed at decreasing toxicity while maintaining activity. The targeted thiazolium salts were synthesized through an N‐alkylation reaction between the corresponding thiazoles and phenacyl bromides. [ABSTRACT FROM AUTHOR]

A new pyridine-fused selenodiazolium salt, 3-(phenylselanyl)[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride dichloromethane 0.352-solvate, C12H9N2Se2+·Cl-·0.352CH2Cl2, was obtained from the reaction between 2-pyridylselenenyl chloride and phenylselenocyanate. Single-crystal structural analysis revealed the presence of C--H⋯N, C--H⋯Cl-, C--H⋯Se hydrogen bonds as well as chalcogen-chalcogen (Se⋯Se) and chalcogen-halogen (Se⋯Cl-) interactions. Non-covalent interactions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of selenodiazolium moieties arranged in a head-to-tail fashion surrounding disordered dichloromethane molecules. The assemblies are connected by C--H⋯Cl- and C--H⋯N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se⋯Cl-⋯H--C interactions. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of α-haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles with various counterions is reported herein, demonstrating a strategy for directed supramolecular dimerization in the solid state. The compounds were obtained through a recently discovered 1,3-dipolar cycloaddition reaction between nitriles and bifunctional 2-pyridylselenyl reagents, and their structures were confirmed by the X-ray crystallography. α-Haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles exclusively formed supramolecular dimers via four-center Se···N chalcogen bonding, supported by additional halogen bonding involving α-haloalkyl substituents. The introduction of halogens at the α-position of the substituent R in the selenadiazole core proved effective in promoting supramolecular dimerization, which was unaffected by variation of counterions. Additionally, the impact of cocrystallization with a classical halogen bond donor C6F3I3 on the supramolecular assembly was investigated. Non-covalent interactions were studied using density functional theory calculations and topological analysis of the electron density distribution, which indicated that all ChB, XB and HB interactions are purely non-covalent and attractive in nature. This study underscores the potential of halogen and chalcogen bonding in directing the self-assembly of functional supramolecular materials employing 1,2,4-selenadiazoles derived from recently discovered cycloaddition between nitriles and bifunctional 2-pyridylselenyl reagents. [ABSTRACT FROM AUTHOR]

After preliminary ab initio calculations, 3‐phenacyl substituted thiazolium salts, analogs of Alagebrium, were synthesized and investigated in vitro as glycation reaction inhibitors. The most part of investigations focused on the potential of the title compounds to attenuate the formation of fluorescent AGEs as well on their ability to disrupt the cross‐linking formation among glycated proteins. Additionally, the capability of thiazolium salts to deglycate in the reaction of early glycation products with nitroblue tetrazolium was determined. Cytotoxicological properties of the title compounds were evaluated using LDH and MTT assays. The leader compound (3‐[2‐(biphenyl‐4‐yl)‐2‐oxoethyl]‐1,3‐thiazol‐3‐ium bromide) in a 50 mg/kg dose (p.o. 14 days) was further tested within an in vivo carbonyl stress model (rats, methylglyoxal 86.25 mg/kg/d, i.p., 14 days). As a result, the leader‐molecule revealed a high effectiveness against all three examined mechanisms of glycation reaction inhibition in in vitro tests and was able to suppress capacity of methylglyoxal to form AGEs in vivo. [ABSTRACT FROM AUTHOR]