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Now showing items 1 - 16 of 12819

  • The nature of magnetic anomalies in subduction zones

    Gorodnitskii, A. M.   Brusilovskii, Yu. V.   Ivanenko, A. N.   Popov, K. V.   Shishkina, N. A.  

    The analysis of the magnetic survey data suggests the presence of a frontal zone of intense magnetic anomalies in a number of the Pacific island-arc systems. These zones with amplitudes of 100-300 nT are observed within the Kuril-Kamchatka and Aleutian island arc systems, in Southern and Central America, and Alaska. As demonstrated by the solution of the inverse problem and petromagnetic investigation of the rocks, these zones are presumably related to the serpentinite bodies which form as a result of the hydration of the upper mantle peridotites by the oceanic water penetrating through a system of cracks and fractures into the subducting slab at its bend. The rock magnetic studies show that magnetite is the main carrier of magnetization in these serpentinite bodies. Hydration of the subducting slab also causes hydration of the mantle rocks of the overriding plate with the formation of the magnetized serpentinite wedge. The decompaction of ultrabasic rocks under hydration is marked by a decrease in the gravity field and velocities of elastic waves. As the subducting plate loses water, it becomes embrittled and becomes the localization region for the epicenters of the strongest earthquakes. Magnetic survey can be used for revealing the potential sources of catastrophic earthquakes.
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  • National Primary Special Standard for the Unit of Air Flow Velocity Get 150-2012

    Popov, K. V.   Polikarpov, S. A.   Chistyakov, Yu. A.  

    The national primary special standard for the unit of air flow velocity, GET 150-2012, is described. Its operating principle and metrological characteristics are examined. International key comparisons of national standards for air flow velocity confirm that the metrological characteristics of this standard are at a world level.
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  • The Study of Systems and Methods for Scientometric Analysis of Scientific Publications

    Shvets, A. V.   Devyatkin, D. A.   Smirnov, I. V.   Tikhomirov, I. A.   Popov, K. V.   Yarygin, K. N.  

    This paper provides an overview of the methods and systems that are applied for scientometric analysis of scientific publications. Methods to identify promising research directions are described. The results of an experimental study aimed at determining the directions of scientific research within the subject area of "regenerative medicine" by using various methods are presented. Conclusions are made about the prospects and shortcomings of the applied methods. Directions for further research are proposed.
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  • Temperature range for magnetization of oceanic spinel peridotites

    Popov, K. V.   Bazylev, B. A.   Shcherbakov, V. P.  

    Petromagnetic studies of a representative spinel peridotite collection from a number of localities along slowly spreading mid-ocean ridges were performed. It was established that oceanic peridotites usually contain two or more generations of ferrimagnetics formed in assemblages with metamorphic silicates at different temperatures. The crystallization of different magnetite (or magnetite-rich spinel) generations in the rocks is manifested by the appearance of inflection points in the thermomagnetic curves. The particular petrographic features of the metamorphism observed in the peridotites correlate well with the temperatures of the inflection points in the thermomagnetic curves. Generally, the serpentinization of primary minerals in oceanic peridotites starts at 210-225 degrees C (green mesh serpentines and bastites) and finishes at 135-190 degrees C (colorless plate serpentines, hourglass-textured serpentines, and colorless homoaxial bastites). Crystallization of ferrimagnetic grains associated with talc, chlorite, and amphibole in the course of medium-grade metamorphism, which precedes the serpentinization, was observed in the major part of the collection examined and occurred at temperatures higher than 370 degrees C. Seprentinization of metamorphic minerals ( predominantly talc) with the formation of anti-gorite and crystallization of ferrimagnetic grains in oceanic peridotites occurred at 250-350 degrees C, previous to the serpentinization of primary silicates. Thus, the petromagnetic thermometry of metamorphic events in oceanic peridotites may provide significant progress in the understanding of the geological process accompanying the formation of the oceanic lithosphere in slowly spreading ocean ridges.
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  • Genetic polymorphism of flax Linum usitatissimum based on the use of molecular cytogenetic markers

    Rachinskaya, O. A.   Lemesh, V. A.   Muravenko, O. V.   Yurkevich, O. Yu.   Guzenko, E. V.   Bol'sheva, N. L.   Bogdanova, M. V.   Samatadze, T. E.   Popov, K. V.   Malyshev, S. V.   Shostak, N. G.   Heller, K.   Hotyleva, L. V.   Zelenin, A. V.  

    Using a set of approaches based on the use of molecular cytogenetic markers (DAPI/C-banding, estimation of the total area of DAPI-positive regions in prophase nuclei, FISH with 26S and 5S rDNA probes) and the microsatellite (SSR-PCR) assay, we studied genomic polymorphism in 15 flax (Linum usitatissimum L.) varieties from different geographic regions belonging to three directions of selection (oil, fiber, and intermediate flax) and in the k-37 x Viking hybrid. All individual chromosomes have been identified in the karyotypes of these varieties on the basis of the patterns of differential DAPI/C-banding and the distribution of 26S and 5S rDNA, and idiograms of the chromosomes have been generated. Unlike the oil flax varieties, the chromosomes in the karyotypes of the fiber flax varieties have, as a rule, pericentromeric and telomeric DAPI-positive bands of smaller size, but contain larger intercalary regions. Two chromosome rearrangements (chromosome 3 inversions) were detected in the variety Luna and in the k-37 x Viking hybrid. In both these forms, no colocalization of 26S rDNA and 5S rDNA on the satellite chromosome was detected. The SSR assay with the use of 20 polymorphic pairs of primers revealed 22 polymorphic loci. Based on the SSR data, we analyzed genetic similarity of the flax forms studied and constructed a genetic similarity dendrogram. The genotypes studied here form three clusters. The oil varieties comprise an independent cluster. The genetically related fiber flax varieties Vita and Luna, as well as the landrace Lipinska XIII belonging to the intermediate type, proved to be closer to the oil varieties than the remaining fiber flax varieties. The results of the molecular chromosome analysis in the fiber and oil flax confirm their very close genetic similarity. In spite of this, the combined use of the chromosome and molecular markers has opened up unique possibilities for describing the genotypes of flax varieties and creating their genetic passports.
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  • "Space" Pea Pisum sativum L. and Wheat Triticum compactum Host. Plants as Objects of Cytogenetic Studies

    Samatadze, T. E.   Badaeva, E. D.   Popov, K. V.   Bolsheva, N. L.   Levinskikh, M. A.   Sychev, V. N.   Amosova, A. V.   Zoshchuk, S. A.   Yurkevich, O. Yu.   Muravenko, O. V.  

    The peculiarities of meiosis, C-heterochromatin (C-HC) distribution, and the activity of nucleolus organizer regions (NORs) of the chromosomes were studied in the Pisum sativum L. pea and Triticum compactum Host. club wheat grown from the seeds obtained in Lada space greenhouse on the board of RS ISS. It was noted that the analysis of meiosis detected no significant violations in the space plant cells, and the total amount of C-HC did not differ significantly from the control, despite the polymorphism of the chromosome C-banding pattern. Paracentric inversion on the chromosome 4A was found for the first time in the T. compactum, while no additional active NOR chromosomes were found.
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  • Comparative cytogenetic study of the forms of Macleaya cordata (Willd.) R. Br. From different localities

    Samatadze, T. E.   Zelenin, A. V.   Suslina, S. N.   Amosova, A. V.   Popov, K. V.   Zagumennikova, T. N.   Tsytsylin, A. N.   Bykov, V. A.   Muravenko, O. V.  

    A comparative cytogenetic study of two introduced forms of Makleaya cordata (Willd.) R. Br. = syn. Bocconia cordata Willd. grown in different ecological and geographical regions (Moscow and Donetsk areas) was carried out. In the study, a complex of methods utilizing various chromosomal markers, i.e., C- and DAPI-banding technique, fluorescence in situ hybridization (FISH) with probes of 26S and 5S rDNA, as well as estimation of the total area of C-positive regions (C-HCH) in prophase nucleoli and meiosis analysis, was used. In the karyotypes (2n = 20), each chromosome was identified on the basis of C-banding and FISH patterns and the chromosome ideograms were built. Pericentrometric and telomeric C-positive bands in chromosomes of the Moscow form karyotype were found to be smaller and intercalary bands, larger than the corresponding bands in the M. cordata form grown in Donetsk. It was found that the content of C-HCH in prophase nucleoli in the form of M. cordata grown in Donetsk was higher than in the form grown in Moscow. In both forms sites of 26S rDNA and 5s rDNA were localized on satellite chromosome 1 and on chromosome 4 respectively but the signals were more intensive in the plant form grown in Donetsk. The results of this study enable selecting M. cordata forms for use in pharmacology and recommending them for cultivation in various ecological and geographical regions.
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  • Comparative genome analysis in pea Pisum sativum L. Varieties and Lines with chromosomal and molecular markers

    Shostak, N. G.   Volkov, A. A.   Popov, K. V.   Rachinskaya, O. V.   Tihonovich, I. A.   Zelenin, A. V.   Muravenko, O. V.  

    C banding, Ag-NOR staining, FISH with pTa71 (45S rDNA) and pTa794 (5S rDNA), and RAPD-PCR analysis were used to study the genome and chromosome polymorphism in four varieties (Frisson, Sparkle, Rondo, and Finale) and two genetic lines (Sprint-2 and SGE) of pea Pisum sativum L. A comparison of the C-banding patterns did not reveal any polymorphism within the varieties. The most significant between-variety differences were observed for the size of C bands on satellite chromosomes 4 and 7. All grain pea varieties (Frisson, Sparkle, and Rondo) had a large C band in the satellite of chromosome 4 and a medium C band in the region adjacent to the satellite thread on chromosome 7. C bands were almost of the same size in the genetic lines and vegetable variety Finale. In all accessions, 45S rDNA mapped to the secondary constriction regions of chromosomes 1, 3, and 5. The signal from chromosome 5 in the lines was more intense than in the varieties. Ag-NOR staining showed that the transcriptional activity of the 45S rRNA genes on chromosome 7 was higher than on chromosome 4 in all accessions. No more than four Ag-NOR-positive nucleoli were observed in interphase nuclei. Statistical analysis of the total area of Ag-NOR-stained nucleoli did not detect any significant difference between the accessions examined. RAPD-PCR analysis revealed high between-variety and low within-variety genomic polymorphism. Chromosomal and molecular markers proved to be promising for genome identification in pea varieties and lines.
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  • A Carneades reconstruction of Popov v Hayashi

    Thomas F. Gordon   Douglas Walton  

    Carneades is an open source argument mapping application and a programming library for building argumentation support tools. In this paper, Carneades' support for argument reconstruction, evaluation and visualization is illustrated by modeling most of the factual and legal arguments in Popov v Hayashi.
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  • A Carneades reconstruction of Popov v Hayashi

    Gordon, T.F.   Walton, D.  

    Carneades is an open source argument mapping application and a programming library for building argumentation support tools. In this paper, Carneades' support for argument reconstruction, evaluation and visualization is illustrated by modeling most of the factual and legal arguments in Popov v Hayashi.
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  • Introduction to special issue on modelling Popov v. Hayashi

    Katie Atkinson  

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  • Introduction to special issue on modelling Popov v. Hayashi

    Katie Atkinson  

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  • ADAM23 is a negative regulator of K(v)1.1/K(v)1.4 potassium currents

    Lancaster, Eunjoo   Burnor, Elisabeth   Zhang, Junxian   Lancaster, Eric  

    Background ADAM22 and ADAM23 are transmembrane proteins that bind the secreted synaptic protein LGI1 and associate with K(v)1.1/K(v)1.4 potassium channels. However, the roles of these proteins in regulated voltage-gated potassium currents are poorly understood. Methods Cultured cells were transfected to express ADAM22, ADAM23, and K(v)1.1/K(v)1.4. Voltage-gated potassium currents were measured by whole-cell patch-clamp. Immunostaining K(v)1.1 with fluorescent antibodies and fluorescently tagged K(v)1.1 subunits was used to measure the effects of ADAM proteins on cell-surface and total expression of K(v)1.1 channels. LGI1-conditioned media was added to assess the effect on LGI1 on K(v)1.1 currents. Results Cells transfected with K(v)1.1/K(v)1.4 showed voltage-gated potassium currents (Kv1.1 currents). ADAM23 was a powerful negative regulator of K(v)1.1 currents and caused decreased surface expression of K(v)1.1 subunits. This decrease in current was not mediated by clathrin-dependent endocytosis. LGI1-conditioned media did not affect the negative regulation of K(v)1.1 currents by ADAM23. ADAM22 had no significant effect on K(v)1.1 currents by itself, but in the presence of LGI1-conditioned media markedly potentiated K(v)1.1 currents without changing channel activation kinetics. Conclusions ADAM22 and ADAM23 have opposite effects on K(v)1.1 currents. The relative expression of these proteins, and the availability of LGI1 may shape the expression of K(v)1.1 currents in different neuronal membrane domains.
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  • NA62 spectrometer to search for K+ -> pi(+)v(v)over-bar

    Shkarovskiy, S.  

    The NA62 experiment at CERN is aimed at measuring the ultra-rare decay K+ -> pi(+)v (v) over bar with 10% accuracy. Since the branching fraction of this decay is O(10(-10)), the detector must be able to suppress background events with branching ratios up to 10 orders of magnitude higher than the signal. In order to achieve this goal a set of modern detector systems has been designed and built. Among them is a low mass (similar to 1.8% X-0) spectrometer to detect charged kaon decay products. The spectrometer contains 7168 straw tubes operating in vacuum. The detector was successfully installed and commissioned in 2014-2015. The goal of this report is to give a general overview of the system. The track time resolution obtained from reconstructed data is also described.
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  • In-flight Search for K+ -> pi(+)v(v)over-bar: First NA62 Results

    Ceccucci, Augusto  

    In this paper the prospects to make a precise measurement of the K+ -> pi(+)v (v) over bar decay using a new kaon decay in-flight technique are reviewed. A preliminary result based on data collected in 2016 yielded one candidate event, compatible with the Standard Model prediction. Assuming that the event is background, an upper limit of 1.4 x 10(-9) (95% CL) has been placed. NA62 is currently taking data: it is expected that with the full data sample recorded before the CERN long shutdown 2 (LS2), the experiment will have about 20 SM events.
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  • Physicalism by K. V. Wilkes

    A. H. Lesser;  

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