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We show that the spin-lattice relaxation in n-type insulating GaAs is dramatically accelerated at low magnetic fields. The origin of this effect, which cannot be explained in terms of well-known diffusion-limited hyperfine relaxation, is found in the quadrupole relaxation, induced by fluctuating donor charges. Therefore, quadrupole relaxation, which governs low field nuclear spin relaxation in semiconductor quantum dots, but was so far supposed to be harmless to bulk nuclei spins in the absence of optical pumping, can be studied and harnessed in the much simpler model environment of n-GaAs bulk crystal. [ABSTRACT FROM AUTHOR]

The thermal quasiparticle random-phase approximation is combined with the Skyrme energy density functional method (Skyrme-TQRPA) to study the response of a hot nucleus to an external perturbation. For the sample nuclei 56Fe and 82Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the strength function of charge-neutral Gamow-Teller transitions, which dominate neutrino-nucleus reactions at Eν≲20 MeV. For the relevant supernova temperatures we calculate the cross sections for inelastic neutrino scattering. We also apply the method to examine the rate of neutrino-antineutrino pair emission by hot nuclei. The cross sections and rates are compared with those obtained earlier from the TQRPA calculations based on the phenomenological quasiparticle-phonon model Hamiltonian. For inelastic neutrino scattering on 56Fe we also compare the Skyrme-TQRPA results to those obtained earlier from a hybrid approach that combines shell-model and RPA calculations. [ABSTRACT FROM AUTHOR]

The optical spin orientation effect in a GaAs/(Ga,Al)As quantum well containing a high-mobility two-dimensional electron gas was found to be due to spin-polarized minority carriers, the holes. The observed oscillations of both the intensity and polarization of the photoluminescence in a magnetic field are well described in a model whose main elements are resonant absorption of the exciting light by the Landau levels and mixing of the heavy- and light-hole subbands. After subtraction of these effects, the observed influence of magnetic fields on the spin polarization can be well interpreted by a standard approach of the optical orientation method. The spin relaxation of holes is controlled by the Dyakonov-Perel' mechanism. Deceleration of the spin relaxation by the magnetic field occurs through the Ivchenko mechanism--due to the cyclotron motion of holes. Mobility of holes was found to be two orders of magnitude smaller than that of electrons, being determined by the scattering of holes by the electron gas. [ABSTRACT FROM AUTHOR]

We develop a superoperator coupled cluster method for nonequilibrium open many-body quantum systems described by the Lindblad master equation. The method is universal and applicable to systems of interacting fermions, bosons or their mixtures. We present a general theory and consider its application to the problem of quantum transport through the system with electron–phonon correlations. The results are assessed against the perturbation theory and nonequilibrium configuration interaction theory calculations. [ABSTRACT FROM AUTHOR]

Transformation of the world population age structure happens at a fast pace and creates problems of increasing social expenditures. However, Industry 4.0 technologies create large-scale opportunities for extending the labor activity of the older population. In Russia, share of people over working age is 22%, and it will increase by another 15% in next 30 years. At the same time, older people are discriminated in the labor market. The article is devoted to the study of job and salary discrimination of elderly workers in the Republic of North Ossetia-Alania as a typical Russian region with tight labor market and a deteriorating demographic situation. Methods of statistical and graphical analysis, factual and sociological research were used. Conclusions have been drawn about the predominance of the model of preserving the employment of older workers in public administration, education, science and health care; the influence of the indexation rate of pensions for non-working pensioners on their informal employment; the preservation of wage disparities for older people employed in the regional economy. The internal gender and age discrimination that has developed in the field of remuneration of older age groups has been revealed: discrimination of women's labor in all age cohorts and types of employment; inter-cohort discrimination of older men's labor within one type of employment; discrimination of wage growth rates of employees of different types of employment. Measures to improve the efficiency of regulating the employment of older workers are proposed.

Russia, like a number of other countries, is experiencing a process of population aging, which is leading to an increased role in the employment of the older generation, while at the same time, employers have a negative perception of their labor potential. The article is devoted to substantiating the hypothesis that employment of older people is an important factor in demographic development. The object of the study is North Ossetia as a typical region of Russia with a worsening demographic situation and tension in the labor market. The work used methods of statistical and graphical analysis, the "resume test" method. The problem of discrimination in hiring workers of pre-retirement age. It has been shown that limited opportunities in the labor market for the older generation lead to a decrease in the level and quality of life, and degradation of human potential. Conclusions are drawn about a decrease in the efficiency of the regional labor market in terms of employment of the elderly. Recommendations are offered to regional bodies of state regulation of the economy on the institutional prevention of the practice of age discrimination among employees; development of flexible part-time employment models; organization of continuous professional training and advanced training.

[Display omitted] • A total of 278 complete genome amino acid sequences were used to delineate species within the tick-borne flavivirus group using three delimitation methods. • The comparative analysis of 812 viral antigenic determinants sequences of four tick-borne encephalitis virus subtypes and louping-ill virus was conducted in silico. • Based on the results obtained, four species have been proposed within the tick-borne encephalitis + louping ill virus paraphyletic group: Flavivirus zilber, Flavivirus neudoerfl, Flavivirus loupingill, Flavivirus mediterraneum. The tick-borne flavivirus (TBFV) group contains at least 12 members where five of them are important pathogens of humans inducing diseases with varying severity (from mild fever forms to acute encephalitis). The taxonomy structure of TBFV is not fully clarified at present. In particular, there is a number of paraphyletic issues of tick-borne encephalitis virus (TBEV) and louping-ill virus (LIV). In this study, we aimed to apply different bioinformatic approaches to analyze all available complete genome amino acid sequences to delineate TBFV members at the species level. Results showed that the European subtype of TBEV (TBEV-E) is a distinct species unit. LIV, in turn, should be separated into two species. Additional analysis of TBEV and LIV antigenic determinant diversity also demonstrate that TBEV-E and LIV are significantly different both from each other and from the other TBEV subtypes. The analysis of available literature provided data on other virus phenotypic particularities that supported our hypothesis. So, within the TBEV + LIV paraphyletic group, we offer to assign four species to get a more accurate understanding of the TBFV interspecies structure according to the modern monophyletic conception. [ABSTRACT FROM AUTHOR]

Relevance. Yersinia pseudotuberculosis is a causative agent of pseudotuberculosis, a disease with polymorphism of clinical manifestation that is determined by the presence of specific virulence determinants: plasmid pVM82, pathogenicity islands HPI and YAPI, and superantigen YPM. Occurrence of new determinants depends on horizontal transfer of mobile genetic elements, hence, systems regulating horizontal transfer participate in evolution of pathogenic species. CRISPR-Cas is and adaptive protection system of prokaryotes against mobile genetic elements. Aim. The study analyzed an interaction between CRISPR-loci of Y. pseudotuberculosis and virulence determinants. Results. 86% of strains includes three CRISPR-loci: YP1, YP2, and YP3. Length of locus YP3 mostly depends on presence of virulence determinants in strains of Y. pseudotuberculosis serotype O:1b. Strains with virulence genes are able to cause a severe form of pseudotuberculosis and have longer locus than strains without determinants. Conclusion. Therefore, CRIPSRCas system of Y. pseudotuberculosis may participate in formation of a certain strain genotype that defines clinical manifestation of pseudotuberculosis.

Labor migration is a key factor in regional demo-economic processes. On the one hand, it plays a significant role in achieving balanced employment. In this sense, it plays a significant role in achieving of the labor markets efficiency. On the other hand, labor migration, as a leading factor in the general migration of the population, along with births and deaths, affects the demographic development of territories. The study of the dual nature of labor migration in the «economy-population» system is an important area of predictive analytics and population movement modeling. The article is devoted to the study of the factors of labor migration dynamics in the region and the assessment of its impact on the natural movement of the population. The object of the study is North Ossetia, as a Russian region with a stable negative migration balance and a deteriorating demographic situation. The work used the methods of a sociological survey, as well as cliometric, statistical, graphical and regression analysis. Sociological studies have shown that the level of development of the labor market has a decisive influence on the migration behavior of the young population. The results of the regression analysis performed in the Excel showed a high and strong inverse relationship between the indicators of the natural population movement and the labor migration of young people. The scientific novelty of the research lies in the development of a systematic methodology for studying the demo-economic processes of the region in order to model effective interregional labor migration in Russia.

Informal employment covers significant segments of the Russian population. This prevents the increase of poverty, inequality and the growth of well-being, creating «traps» of sustainable development. The article is devoted to the study of the main causes of the spread of informal employment in the labor market of Russian regions using expert analytical methods, analysis of statistical data series and clustering. Classification of regions was built on the basis of the k-means algorithm, which made it possible to minimize variance within regional groups and build clusters based on weighted standardized data. In each cluster, regions have similar characteristics in terms of criteria for the ratio of shadow employment and income. This study is one of the first attempts to cluster regions using Ward's hierarchical method according to the criteria «income of the population - informal employment». Clusters of Russian regions constructed and visualized using the RStudio programming language showed that informal employment strongly correlates with the «low welfare» zone: the lower incomes of the population, the greater part of it works informally. The scientific novelty of the study is to identify the main factor of high informal employment in Russian regions - relative and absolute poverty of the population. The practical significance of reducing shadow employment lies not only in improving the efficiency of regulation of regional labor markets, increasing the revenues of the budget system and the standard of living of the population, but also in modernizing approaches to ensuring the demographic security of the regions of Russia.

It has been commonly decided to retract this article on the grounds that one of the authors, Lira Gurieva, has used material without due knowledge of all parties involved in the results obtained within this research article. The author apologizes for the inadvertent misappropriation of the data. The Authors, the Publisher and Editor approved to the retraction.

It has been commonly decided to retract this article on the grounds that one of the authors, Lira Gurieva, has used material without due knowledge of all parties involved in the results obtained within this research article. The author apologizes for the inadvertent misappropriation of the data. The Authors, the Publisher and Editor approved to the retraction.

The behavior of the electron spin relaxation time in bulk GaAs layers doped with Mn was studied experimentally. We investigated the dependence of the degree of circular polarization of photoluminescence in transverse and longitudinal magnetic fields. An increase in the relaxation time of the electron spin is found from 25 ns at low pumping power to 400 ns at the threshold pumping power. The effect of resonant cooling of the nuclear spin system by optically-oriented electron spins is demonstrated. [ABSTRACT FROM AUTHOR]

The aim of this research was to analyze and compare CRIPSR loci and cas-proteins of Yersinia pseudotuberculosis strains isolated in different territories from patients with various clinical manifestations of pseudotuberculosis.Materials and Methods. Complete genomes of Y. pseudotuberculosis IP329353 (NC_006155) and IP31758 (NC_009708) were obtained from NCBI Nucleotide Database. Strains were isolated from patients with gastroenteritis and systemic infection respectively. Search, identification, and analysis of CRISPR systems were carried out by onlinetools CRISPROne, CRISPRDetect, and CRISPRTarget.Results. Analyzed strains have CRISPR-Cas systems that include one set of cas-genes and arrays situated at the long distances from each other. We defined three CRISPR arrays in Y. pseudotuberculosis IP32953: array YP1 located near cas-genes, arrays YP2 and YP3. CRISPR-Cas system of Y. pseudotuberculosis IP31758 includes two arrays – YP1 and YP3. CRISPR systems do not share similar spacers.Conclusion. CRISPR systems of the analyzed strains differ in CRISPR loci and cas-protein structures that can be used as specific molecular marks of analyzed strains during the study of intra-species variability and evolution of Y. pseudotuberculosis.

The first excited level of 96Mo was investigated in a high-statistics experiment using the 95Mo(n, γγ) cold neutron capture reaction. The measurements used the high cold neutron flux from the research reactor at Institut Laue-Langevin and employed the highly-efficient EXILL array to detect γ-ray coincidences. The recorded statistics allow identification of decay branches with only a small relative intensity including the E3 decay. With the knowledge of the newly measured branching ratio and the known transition probability, the lifetime of the level was determined and, subsequently, the strength of the other decay branches of the octupole phonon were calculated. The extracted electromagnetic decay strengths are compared to the systematics of the stable even–even molybdenum isotopes and values calculated in a Skyrme-force based quasiparticle random phase approximation and in a cluster approach. Additionally, the decay branch to the low-lying quadrupole isovector level was observed. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the ecology features of tick-borne encephalitis virus (TBEV) of European subtype circulating in Siberia. The strains of European subtype TBEV from Siberia were isolated in areas with different terrain types - from the plains to the midlands. The strains isolation areas differed in variety of landscapes, flora and fauna and were characterized by the presence of sharp-continental, or in some places - quite harsh climate. The composition of the main vectors and reservoir hosts of TBEV of European subtype in Siberia has its own features and is significantly different from that one in Europe. However, in spite of this, the homology of TBEV strains of European subtype isolated in different parts of habitat range of the virus from the Scandinavian countries in the West to its Eastern borders is much higher than the homology level degree of TBEV strains of FarEastern and Siberian subtypes.

The aim of the study was to obtain the complex characteristics of tick-borne encephalitis virus (TBEV) of European subtype circulating in Western and Eastern Siberia. Using full-genome sequencing approach it was demonstrated that TBEV strains of European subtype isolated in Siberia are genetically similar to the strains from European part of its habitat range, and with the representatives from South Korea. It was confirmed that the homology of TBEV strains of European subtype isolated in different parts of the virus habitat area from Scandinavian countries in the west to the eastern borders of the area (South Korea) is much higher than the homology level of TBEV strains of Far Eastern and Siberian subtypes. The Siberian population of TBEV of European subtype is presented with two groups of strains called as Eastern Siberian and Western Siberian variants, which differ in the combinations of amino acid substitutions in all proteins except NS2B protein. It is found that TBEV strains of European subtype from Siberia possess high neurovirulence, but some of them, like strains from Europe, demonstrate low invasiveness. It is shown that TBEV strains of European subtype have good adaptive capacity, and therefore, can easily adapt to the circulation in various biocenoses in the territory of different landscape-geographical zones. It was found that the circulation of TBEV of European subtype is fixed in Siberia territory for over 40 years. It was emphasized that in spite of circulation of TBEV of European subtype in the significantly different areas by climatic conditions, topography, landscape, habitat characteristics it possesses a high degree of genome stability.

A motivating factor for performing amalgamation and merger is synergetic effect, creation of new opportunities for business development, increase in compatibility and financial viability of a new organization. However, up to 70% of all transactions are not efficient and lead to splitting of the united company. The article examines new instruments used in conducting such transactions. The principles of rising integration process efficiency are rationalized.

The methods of mathematical processing of the envelopes of spin‐echo signals have been considered within the framework of the multiphase relaxation theory. A mathematical model for separation of multiexponential relaxation curves into individual exponential components of spin‐spin relaxation times T2i and amplitudes Ii is described. The multiphase nature of the relaxation of protons in complex heterogeneous systems has been revealed, and the relaxation characteristics of individual components — spin‐spin relaxation times and amplitudes — have been determined. [ABSTRACT FROM AUTHOR]

• Samples from complete genomes of SARS-CoV-2 isolated during the first wave (December 2019–July 2020) of the global COVID-19 pandemic from 21 countries (Asia, Europe, Middle East and America) around the world, were analyzed using the phylogenetic method with the molecular clock dating. • Results showed that the first cases of COVID-19 in the human population appeared in the period between July and November 2019 in China and spread into other countries of the world began in the autumn of 2019. In mid-February 2020. • The rate of evolution of the coding of the SARS-CoV-2 genome equal to 7.3 × 10−4 (5.95 × 10−4–8.68 × 10−4) nucleotide substitutions per site per year is comparable to those of other human RNA viruses (Measles morbillivirus, Rubella virus, Enterovirus C). Samples from complete genomes of SARS-CoV-2 isolated during the first wave (December 2019–July 2020) of the global COVID-19 pandemic from 21 countries (Asia, Europe, Middle East and America) around the world, were analyzed using the phylogenetic method with molecular clock dating. Results showed that the first cases of COVID-19 in the human population appeared in the period between July and November 2019 in China. The spread of the virus into other countries of the world began in the autumn of 2019. In mid-February 2020, the virus appeared in all the countries we analyzed. During this time, the global population of SARS-CoV-2 was characterized by low levels of the genetic polymorphism, making it difficult to accurately assess the pathways of infection. The rate of evolution of the coding region of the SARS-CoV-2 genome equal to 7.3 × 10−4 (5.95 × 10−4–8.68 × 10−4) nucleotide substitutions per site per year is comparable to those of other human RNA viruses (Measles morbillivirus, Rubella virus, Enterovirus C). SARS-CoV-2 was separated from its known close relative , the bat coronavirus RaTG13 of the genus Betacoronavirus, approximately 15–43 years ago (the end of the 20th century). [ABSTRACT FROM AUTHOR]

The dynamic polarization of nuclear spins by photoexcited electrons is studied in a high quality GaAs/AlGaAs quantum well. We find a surprisingly high efficiency of the spin transfer from the electrons to the nuclei as reflected by a maximum nuclear field of 0.9 T in a tilted external magnetic field of 1 T strength only. This high efficiency is due to a low leakage of spin out of the polarized nuclear system, because mechanisms of spin relaxation other than the hyperfine interaction are strongly suppressed, leading to a long nuclear relaxation time of up to 1000 s. A key ingredient to that end is the low impurity concentration inside the heterostructure, while the electrostatic potential from charged impurities in the surrounding barriers becomes screened through illumination by which the spin relaxation time is increased compared to keeping the system in the dark. This finding indicates a strategy for obtaining high nuclear spin polarization as required for long-lasting carrier spin coherence. [ABSTRACT FROM AUTHOR]

Nuclear spin relaxation is studied in n-GaAs thick layers and microcavity samples with different electron densities. We reveal that both in metallic samples where electrons are free and mobile, and in insulating samples where electrons are localized, nuclear spin relaxation is strongly enhanced at low magnetic fields. The origin of this effect could reside in the quadrupole interaction between nuclei and fluctuating electron charges, that has been proposed to govern nuclear spin dynamics at low magnetic fields in the insulating samples. The characteristic values of these magnetic fields are given by dipole-dipole interaction between nuclei in bulk samples, and are greatly enhanced in microcavities, presumably due to additional strain, inherent to microstructures and nanostructures. [ABSTRACT FROM AUTHOR]