66 research outputs found

    Natronoflexus pectinivorans gen. nov. sp. nov., an obligately anaerobic and alkaliphilic fermentative member of Bacteroidetes from soda lakes

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    Anaerobic enrichment with pectin at pH 10 and moderate salinity inoculated with sediments from soda lakes of the Kulunda Steppe (Altai, Russia) resulted in the isolation of a novel member of the Bacteroidetes, strain AP1T. The cells are long, flexible, Gram-negative rods forming pink carotenoids. The isolate is an obligate anaerobe, fermenting various carbohydrates to acetate and succinate. It can hydrolyze and utilize pectin, xylan, starch, laminarin and pullulan as growth substrates. Growth is possible in a pH range from 8 to 10.5, with an optimum at pH 9.5, and at a salinity range from 0.1 to 2 M Na+. Phylogenetic analysis based on 16S rRNA sequences placed the isolate into the phylum Bacteroidetes as a separate lineage within the family Marinilabilaceae. On the basis of distinct phenotype and phylogeny, the soda lake isolate AP1T is proposed to be assigned in a new genus and species Natronoflexus pectinivorans (=DSM24179T = UNIQEM U807T)

    Labour relations in research of socio-economic systems

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    The article is concerned with the study of the theoretical and methodological patterns of the genesis of labour relations during evolution of socio-economic systems. The approach developed by the authors makes it possible to single out the basic blocks of the labour relations system, considering the actors and objects of the relations. Adopted as a basis, such an approach makes it possible to describe the labour relations of any economic system. The allocation of mandatory elements (objects) and subjects in the structure of labour relations makes it possible to disclose the content of the category “labour relations”. The relevance of theoretical studies of the characteristics of the economy at a substantial level, the increased interest in the methodology and theory of economic knowledge is due to the inconsistency and alternativeness of the current stage of development of the world economy and global society. For Russian society, such studies are determined by the exceptional complexity of transformation processes and the prospects for its evolution.peer-reviewe

    Human capital as a base for regional development : a case study

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    Purpose: The main aim of this article is to consider the main trends observed in the labor market in the regional agricultural sector. Design/Methodology/Approach: The study uses the statistical method, the method of analogy and comparison, as well as the positive and normative approach. Findings: The study indicated that in the agricultural sector there are several problems associated with the formation of human resources. This is evidenced by the presence of negative trends that have been observed over the past 20 years. The main problems are the low educational level of workers, aging professional staff, and a reduction in the number of employees in all positions. Practical implications: The socio-economic problems considered in the article indicate the urgent need to develop a mechanism of state support for agricultural workers. Originality/Value: The authors define the concept of human capital and reveal the essence of the factors influencing its formation, revealing them from the perspective of the socio-economic development of the region.peer-reviewe

    ASTRA: ASTrometry and phase-Referencing Astronomy on the Keck interferometer

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    ASTRA (ASTrometric and phase-Referencing Astronomy) is an upgrade to the existing Keck Interferometer which aims at providing new self-phase referencing (high spectral resolution observation of YSOs), dual-field phase referencing (sensitive AGN observations), and astrometric (known exoplanetary systems characterization and galactic center general relativity in strong field regime) capabilities. With the first high spectral resolution mode now offered to the community, this contribution focuses on the progress of the dual field and astrometric modes.Comment: 10 pages, 6 figures, 2 tables, SPIE 201

    Recent progress at the Keck Interferometer

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    The Keck Interferometer (KI) combines the two 10m diameter Keck telescopes providing milliarcsecond angular resolution. KI has unique observing capabilities such as sensitive K-band V^2, L-band V^2 and N-band nulling modes. The instrument improvements and status of the Keck Interferometer since the 2010 SPIE meeting are summarized. We discuss the current capabilities of the KI, operational improvements, and the science from the KI during the past two years. We will conclude with a brief note on the closure of the KI facility. Details of dual field phase referencing developments and nulling science results are presented elsewhere at this conference

    The dusty AGB star RS CrB: first mid-infrared interferometric observations with the Keck Telescopes

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    We report interferometric observations of the semi-regular variable star RS CrB, a red giant with strong silicate emission features. The data were among the first long baseline mid-infrared stellar fringes obtained between the Keck telescopes, using parts of the new nulling beam combiner. The light was dispersed by a low-resolution spectrometer, allowing simultaneous measurement of the source visibility and intensity spectra from 8 to 12 microns. The interferometric observations allow a non-ambiguous determination of the dust shell spatial scale and relative flux contribution. Using a simple spherically-symmetric model, in which a geometrically thin shell surrounds the stellar photosphere, we find that ~30% to ~70% of the overall mid-infrared flux - depending on the wavelength - originates from 7-8 stellar radii. The derived shell opacity profile shows a broad peak around 11 microns (tau ~ 0.06), characteristic of Mg-rich silicate dust particles.Comment: Accepted for publication in ApJ Letter

    Keck Interferometer Nuller Data Reduction and On-Sky Performance

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    We describe the Keck Interferometer nuller theory of operation, data reduction, and on-sky performance, particularly as it applies to the nuller exozodiacal dust key science program that was carried out between 2008 February and 2009 January. We review the nuller implementation, including the detailed phasor processing involved in implementing the null-peak mode used for science data and the sequencing used for science observing. We then describe the Level 1 reduction to convert the instrument telemetry streams to raw null leakages, and the Level 2 reduction to provide calibrated null leakages. The Level 1 reduction uses conservative, primarily linear processing, implemented consistently for science and calibrator stars. The Level 2 processing is more flexible, and uses diameters for the calibrator stars measured contemporaneously with the interferometer’s K-band cophasing system in order to provide the requisite accuracy. Using the key science data set of 462 total scans, we assess the instrument performance for sensitivity and systematic error. At 2.0 Jy we achieve a photometrically-limited null leakage uncertainty of 0.25% rms per 10 minutes of integration time in our broadband channel. From analysis of the Level 2 reductions, we estimate a systematic noise floor for bright stars of ~0.2% rms null leakage uncertainty per observing cluster in the broadband channel. A similar analysis is performed for the narrowband channels. We also provide additional information needed for science reduction, including details on the instrument beam pattern and the basic astrophysical response of the system, and references to the data reduction and modeling tools

    Statistical analysis of the use an internal capital adequacy assessment procedure in the monitoring of banks stability

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    To increase the stability of the banking system, it is necessary to use effective systems of risk management and monitoring of banks. One of these systems is the internal procedure for capital adequacy assessment (IPCAA). The purpose of this study is to assess, using a statistical analysis, the impact of the IPCAA procedure on changes in the value of banks' capital adequacy ratios. Some results of monitoring data are presented on risk-weighted assets, level 1 and 2 capitals, and capital adequacy ratios (CAR) for two foreign (2008 - 2018) and three Russian banks (2014 - 2018). The study showed the direct effect of increasing the risk-weighted assets on the level of capital adequacy (CAR). The results obtained allow concluding that there is a direct significant connection between the IPCAA procedure use and the stability of banks. This procedure provides a comprehensive assessment of the overall capital adequacy of banks, taking into account the existing risks in order to maintain an adequate and stable forecast level of capital. The study also revealed the needs of banks in creating adequate structures to ensure proper management of financial and operational risks, which will simplify the IPCAA process and ensure more effective capital planning and decision-making to provide the stability of both individual banks and the entire banking system. © 2020 American Institute of Physics Inc.. All rights reserved

    Milliarcsecond N-Band Observations of the Nova RS Ophiuchi: First Science with the Keck Interferometer Nuller

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    We report observations of the nova RS Ophiuchi (RS Oph) using the Keck Interferometer Nuller (KIN), approximately 3.8 days following the most recent outburst that occurred on 2006 February 12. These observations represent the first scientific results from the KIN, which operates in N-band from 8 to 12.5 microns in a nulling mode. By fitting the unique KIN data, we have obtained an angular size of the mid-infrared continuum of 6.2, 4.0, or 5.4 mas for a disk profile, gaussian profile (FWHM), and shell profile respectively. The data show evidence of enhanced neutral atomic hydrogen emission and atomic metals including silicon located in the inner spatial regime near the white dwarf (WD) relative to the outer regime. There are also nebular emission lines and evidence of hot silicate dust in the outer spatial region, centered at ! 17 AU from the WD, that are not found in the inner regime. Our evidence suggests that these features have been excited by the nova flash in the outer spatial regime before the blast wave reached these regions. These identifications support a model in which the dust appears to be present between outbursts and is not created during the outburst event. We further discuss the present results in terms of a unifying model of the system that includes an increase in density in the plane of the orbit of the two stars created by a spiral shock wave caused by the motion of the stars through the cool wind of the red giant star. These data show the power and potential of the nulling technique which has been developed for the detection of Earth-like planets around nearby stars for the Terrestrial Planet Finder Mission and Darwin missions.Comment: 41 pages, 10 figure
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