The Phantom Bounce: A New Oscillating Cosmology

An oscillating universe cycles through a series of expansions and contractions. We propose a model in which ``phantom'' energy with $p < -\rho$ grows rapidly and dominates the late-time expanding phase. The universe's energy density is so large that the effects of quantum gravity are important at both the beginning and the end of each expansion (or contraction). The bounce can be caused by high energy modifications to the Friedmann equation, which make the cosmology nonsingular. The classic black hole overproduction of oscillating universes is resolved due to their destruction by the phantom energy.Comment: Four pages, one figure. V3: version to appear in JCA

The Development of Youth Entrepreneurship at a University Taking into the Factor of Cooperation with Partners

The article presents the author’s view on the development of youth entrepreneurship at a university based on the factor of cooperation with partners. The main objective of the study is to establish the methodological framework for the use of the potential of the partners of a university for the development of youth entrepreneurship. The relevance of the study is determined by the need to develop approaches to stimulate the development of youth entrepreneurship in Russia, including at universities. The article considers theoretical and methodological foundations of youth entrepreneurship. The authors defines the stimulatory and constraining factors, as well as endogenous (transformational and transactional) and exogenous conditions for the development of youth entrepreneurship. A comprehensive mechanism is proposed in the context of four main structural units and principles of entrepreneurship taking into account the interaction of the university with its partners - businesses, territorial, educational and scientific communities. The authors systematizes the specific experience of Russian universities in the framework of the functioning elements of an integrated mechanism for the development of youth entrepreneurship, considering interaction with their partners. Common features and differences in the intensity of the support and development of youth entrepreneurship have been identified. The significant role of partners at this stage of the functioning of universities is obvious. Interaction with partners of a university in the development of youth entrepreneurship has a significant potential, based on the relevance of entrepreneurship support as a whole, the need to intensify the development of business activities of individual companies and institutions through the implementation of entrepreneurial initiatives and the social importance of discovering entrepreneurial skills in young people. The universities that have been studied use opportunities to attract external projects that further the development of youth entrepreneurship. The results can be used for analysis of current activity and formation of strategic documents in the field of youth entrepreneurship development for universities, private companies, scientific organizations and public associations.В статье представлен авторский взгляд на развитие молодежного предпринимательства в университете на основе фактора взаимодействия с партнерами. Основная цель исследования состоит в формировании методологической базы для использования потенциала партнеров университета для развития молодежного предпринимательства. Актуальность исследования определяется необходимостью выработки подходов к стимулированию развития молодежного предпринимательства в России, в том числе на базе университетов. В статье рассмотрены теоретико-методологические основы молодежного предпринимательства. Авторами определены стимулирующие и сдерживающие факторы, а также эндогенные (трансформационные и трансакционные) и экзогенные условия развития молодежного предпринимательства. Предложен комплексный механизм в разрезе четырех основных структурных блоков и принципы развития предпринимательства с учетом взаимодействия университета со своими партнерами – деловым, территориальным, образовательным и научным сообществами. Авторами статьи систематизирован частный опыт российских университетов в рамках функционирования элементов комплексного механизма развития молодежного предпринимательства с учетом взаимодействия с партнерами университета. Выявлены общие черты и различие в интенсивности поддержки и развития молодежного предпринимательства. При этом действенная роль партнеров на текущем этапе функционирования университетов очевидна. Взаимодействие с партнерами университета в области развития молодежного предпринимательства имеет значительный потенциал, опирающийся на актуальность поддержки предпринимательства в целом, необходимости интенсификации развития хозяйствующей деятельности отдельных компаний и учреждений за счет реализации предпринимательских инициатив и общественной значимости раскрытия предпринимательских способностей молодежи. Все проанализированные авторами работы университеты используют возможности, способствующие развитию молодежного предпринимательства. Результаты работы могут быть использованы для анализа текущей деятельности, а также формирования стратегических документов в сфере развития молодежного предпринимательства для университетов, частных компаний, научных организации и общественных объединений.Статья выполнена в соответствии с планом НИР Института экономики УрО РАН № темы 0404-2015-0021 в ИСГЗ ФАН

Data Processing Technology for the Forecasting of the Water Inflow into a Reservoir with the Use of Earth Remote Sensing and the Network of Meteorological and Hydrological Posts

Management of the hydropower plants requires the economically efficient use of water resources based on the forecasts and simulation models of the hydropower plant and the reservoir. There are various data sources for the water inflow forecasting: meteorological and hydrological posts, Earth remote sensing. However, the problem arises of combining the specified heterogeneous data for aggregated processing with the use of machine learning methods. The research goal is to design an architecture of a system for collecting and processing the data from various sources to operational forecast of the water inflow and the reservoir water-level. It was achieved by analyzing and selecting the sources and methods for the use of Earth remote sensing data; observing the main principles of hydrological modeling; assessing the availability of the different data; analyzing the ways of increasing the observability of the hydrological objects by installing additional meteorological and hydrological posts; and designing a technology for the automatic data collection and processing. The most significant results are developed architecture of the data collection and processing system and the technology for aggregating heterogeneous data with the use of machine learning methods. It is aimed to reduce the error of short-term forecasting of the water inflow to the reservoir. The significance of the results lies in the fact that the proposed technology was offered and justified for a real hydropower plant; and it can improve the water resources management efficiency: increase the energy generation, minimize the sterile spills, increase the flood forecasting horizon and reduce the risk of flooding during the spring high water. © 2022 Izdatel'stvo Meditsina. All rights reserved

Correlation effects during liquid infiltration into hydrophobic nanoporous mediums

Correlation effects arising during liquid infiltration into hydrophobic porous medium are considered. On the basis of these effects a mechanism of energy absorption at filling porous medium by nonwetting liquid is suggested. In accordance with this mechanism, the absorption of mechanical energy is a result expenditure of energy for the formation of menisci in the pores on the shell of the infinite cluster and expenditure of energy for the formation of liquid-porous medium interface in the pores belonging to the infinite cluster of filled pores. It was found that in dependences on the porosity and, consequently, in dependences on the number of filled pores neighbors, the thermal effect of filling can be either positive or negative and the cycle of infiltration-defiltration can be closed with full outflow of liquid. It can occur under certain relation between percolation properties of porous medium and the energy characteristics of the liquid-porous medium interface and the liquid-gas interface. It is shown that a consecutive account of these correlation effects and percolation properties of the pores space during infiltration allow to describe all experimental data under discussion

Phantom scalar emission in the Kerr black hole spacetime

We study the absorption probability and Hawking radiation spectra of a phantom scalar field in the Kerr black hole spacetime. We find that the presence of the negative kinetic energy terms modifies the standard results in the greybody factor, super-radiance and Hawking radiation. Comparing with the usual scalar particle, the phantom scalar emission is enhanced in the black hole spacetime.Comment: 11 pages, 6 figures, a revised version accepted for publication in CQ

Caspian Sandy Natural Focus: Phylogenetic History and Origin of <i>Yersinia pestis</i> Strains

The purpose of the work was to analyze the phylogenetic relations and origin of Yersinia pestis strains isolated in different periods of epizootic activity of the Caspian sandy natural focus (CSNF) of plague in the XX–XXI centuries.Materials and methods. We used 40 Y. pestis strains from CSNF and adjacent plague foci, isolated in 1922–2015. Carried out was whole genome sequencing of 19 Y. pestis strains from CSNF. Phylogenetic analysis was performed using whole genome SNP analysis based on 1914 identified SNPs. The search for marker SNPs was conducted using the Snippy 4.6 software. The phylogenetic tree was constructed using the Maximum Likelihood algorithm, the GTR nucleotide substitution model.Results and discussion. The whole genome SNP analysis has revealed that Y. pestis strains of the medieval biovar from CSNF belong to 2.MED1 phylogenetic lineage and fall into two major branches. One of them circulated in the focus in the first half of the XX century, and the other – in the second half of the XX – early XXI centuries. It is shown that strains of the first branch were the cause of outbreaks and individual cases of plague in the CSNF in the first half of the XX century. They are closely related to strains from the Caspian North-Western steppe and Volga-Ural sandy natural plague foci, which caused numerous outbreaks with high mortality rate in the same period. Y. pestis strains from the CSNF of the second half of the XX and early XXI centuries belong to the second phylogenetic branch of the 2.MED1 line, at the node of which the strains from the Northern Aral Sea region of 1945 lay. The latter were the predecessors of all strains isolated in the CSNF after a long inter-epizootic period that occurred in the middle of the XX century. There can also be traced a genetic relation between the strains from CSNF and the Dagestan plain-foothill focus

Gamma Ray Bursts from the Evolved Galactic Nuclei

A new cosmological scenario for the origin of gamma ray bursts (GRBs) is proposed. In our scenario, a highly evolved central core in the dense galactic nucleus is formed containing a subsystem of compact stellar remnants (CSRs), such as neutron stars and black holes. Those subsystems result from the dynamical evolution of dense central stellar clusters in the galactic nuclei through merging of stars, thereby forming (as has been realized by many authors) the short-living massive stars and then CSRs. We estimate the rate of random CSR collisions in the evolved galactic nuclei by taking into account, similar to Quinlan & Shapiro (1987), the dissipative encounters of CSRs, mainly due to radiative losses of gravitational waves, which results in the formation of intermediate short-living binaries, with further coalescence of the companions to produce GRBs. We also consider how the possible presence of a central supermassive black hole, formed in a highly evolved galactic nucleus, influences the CSR binary formation. This scenario does not postulate ad hoc a required number of tight binary neutron stars in the galaxies. Instead, it gives, for the most realistic parameters of the evolved nuclei, the expected rate of GRBs consistent with the observed one, thereby explaining the GRB appearance in a natural way of the dynamical evolution of galactic nuclei. In addition, this scenario provides an opportunity for a cosmological GRB recurrence, previously considered to be a distinctive feature of GRBs of a local origin only. We also discuss some other observational tests of the proposed scenario.Comment: 25 pages, LATEX, uses aasms4.sty, accepted by Ap

Variability of <i>phoP/phoQ</i> and <i>rovA</i> Genes Sequences - Global Regulators of the Plague Agent Life Span

Compared are the gene sequences of the global phoP/phoQ and rovA transcription regulators in original Yersinia pestis strains of different subtypes. Detected is overall identity of the sequenced phoQ fragment and high conservatism of the rovA gene. All the plague agent strains belonging to the main subspecies have a missense mutation in phoP gene. It is a substitution of a single nucleotide G→A in the position 643 from the beginning of the gene, which causes amino-acid residue shift Gly→Ser in the position 215 in polypeptide chain of the PhopP protein, and, is a possible cause of alteration of the PhoP transcription activity in Yersinia pestis strains belonging to the main subspecies

Dark energy cosmology with generalized linear equation of state

Dark energy with the usually used equation of state $p=w\rho$, where $w=const<0$ is hydrodynamically unstable. To overcome this drawback we consider the cosmology of a perfect fluid with a linear equation of state of a more general form $p=\alpha(\rho-\rho_0)$, where the constants $\alpha$ and $\rho_0$ are free parameters. This non-homogeneous linear equation of state provides the description of both hydrodynamically stable ($\alpha>0$) and unstable ($\alpha<0$) fluids. In particular, the considered cosmological model describes the hydrodynamically stable dark (and phantom) energy. The possible types of cosmological scenarios in this model are determined and classified in terms of attractors and unstable points by the using of phase trajectories analysis. For the dark energy case there are possible some distinctive types of cosmological scenarios: (i) the universe with the de Sitter attractor at late times, (ii) the bouncing universe, (iii) the universe with the Big Rip and with the anti-Big Rip. In the framework of a linear equation of state the universe filled with an phantom energy, $w<-1$, may have either the de Sitter attractor or the Big Rip.Comment: 12 pages, 11 figures, typos corrected, references adde

Structural-Functional Analysis of Cryptic Plasmids in <i>Yersinia pestis</i> Strains from Two Natural Plague Foci of Russia

Identified are the complete nucleotide sequences of two cryptic plasmids - pCKF from the Central-Caucasian high-mountain plague focus and pTP33 - from Tuva mountain plague focus in Russia. It is established that the size of the pCKF is 5.4 kbp, and its G-C pair composition accounts for 38.4 %. The plasmid contains 8 open reading frames, encoding transport and secretion functions, in particular, secretion systems of the VI type. The size of another cryptic plasmid, pTP33, is 33.8 kbp, and G-C pair composition accounts for 50.3 %. It contains 52 open reading frames, the majority of which have been classified as phage proteins. Hence, it is inferred that pTP33 is a ring genome of phage. It also has two genes of two-component protein system, toxin-antitoxin, YoeB/YefM, that affects replication apparatus of bacteria