65 research outputs found

    Potential for Development and Limitations of Regional Business Environment

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    The article considers some questions of institutional support for the development of the regional business environment. In connection with constantly growing social liabilities of regional and municipal authorities, which results in the upsurge of risks of budget imbalance at respective levels, the research provides a foundation to the necessity of forming favorable business environment promoting enterprise activity in regions. The process of creating institutes of a region’s business environment is analyzed with applying a matrix institutional model of entrepreneurship. The article reveals the mechanism stipulating the emergence of specific peculiarities of institutional configurations of the regional business environment. A conclusion is drawn about the decisive role of the institutional configuration of the business environment in the existing differences in the levels of social and economic development of regions. The researchers put forward a hypothesis that supporting a favorable institutional configuration of a region’s business environment that stimulates enterprise activity in the area cannot last indefinitely as its development is of a cyclical nature. Simulation parameters for the formation and maintenance of a favorable institutional configuration of the business environment are given. With the aim of practical application of the suggested approach, the authors suggest a methodology allowing for regional authorities to estimate the expediency of favorable institutional configuration of business environment, and on this basis to formulate rules of play for business so that these rules could boost business activity and increase the contribution of entrepreneurship to the region’s social and economic development. The approach under consideration provides an opportunity to substantiate a theoretical and methodological framework for developing practical mechanisms of projecting and further long-term maintenance of favorable institutional configuration of business environment which will contribute to expanding the region’s business activity, and which is resistant to negative effects of the external environment.Work produced with the financial support of the grant FSBI “Russian Humanitarian Science Foundation” in the framework of scientific — research project “Interaction of authority and business organizations in the municipalities: through compromise to mutual loyalty» № 15-12-02008

    Insertions and the emergence of novel protein structure: a structure-based phylogenetic study of insertions

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    <p>Abstract</p> <p>Background</p> <p>In protein evolution, the mechanism of the emergence of novel protein domain is still an open question. The incremental growth of protein variable regions, which was produced by stochastic insertions, has the potential to generate large and complex sub-structures. In this study, a deterministic methodology is proposed to reconstruct phylogenies from protein structures, and to infer insertion events in protein evolution. The analysis was performed on a broad range of SCOP domain families.</p> <p>Results</p> <p>Phylogenies were reconstructed from protein 3D structural data. The phylogenetic trees were used to infer ancestral structures with a consensus method. From these ancestral reconstructions, 42.7% of the observed insertions are nested insertions, which locate in previous insert regions. The average size of inserts tends to increase with the insert rank or total number of insertions in the variable regions. We found that the structures of some nested inserts show complex or even domain-like fold patterns with helices, strands and loops. Furthermore, a basal level of structural innovation was found in inserts which displayed a significant structural similarity exclusively to themselves. The β-Lactamase/D-ala carboxypeptidase domain family is provided as an example to illustrate the inference of insertion events, and how the incremental growth of a variable region is capable to generate novel structural patterns.</p> <p>Conclusion</p> <p>Using 3D data, we proposed a method to reconstruct phylogenies. We applied the method to reconstruct the sequences of insertion events leading to the emergence of potentially novel structural elements within existing protein domains. The results suggest that structural innovation is possible via the stochastic process of insertions and rapid evolution within variable regions where inserts tend to be nested. We also demonstrate that the structure-based phylogeny enables the study of new questions relating to the evolution of protein domain and biological function.</p

    Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

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    The decay channel ψπ+πJ/ψ(J/ψγppˉ)\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) is studied using a sample of 1.06×1081.06\times 10^8 ψ\psi^\prime events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the ppˉp\bar{p} invariant mass spectrum. The enhancement can be fit with an SS-wave Breit-Wigner resonance function with a resulting peak mass of M=186113+6(stat)26+7(syst)MeV/c2M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2 and a narrow width that is Γ<38MeV/c2\Gamma<38 {\rm MeV/}c^2 at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics

    Observation of χc1\chi_{c1} decays into vector meson pairs ϕϕ\phi\phi, ωω\omega\omega, and ωϕ\omega\phi

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    Decays of χc1\chi_{c1} to vector meson pairs ϕϕ\phi\phi, ωω\omega\omega and ωϕ\omega\phi are observed for the first time using (106±4)×106(106\pm4)\times 10^6 \psip events accumulated at the BESIII detector at the BEPCII e+ee^+e^- collider. The branching fractions are measured to be (4.4±0.3±0.5)×104(4.4\pm 0.3\pm 0.5)\times 10^{-4}, (6.0±0.3±0.7)×104(6.0\pm 0.3\pm 0.7)\times 10^{-4}, and (2.2±0.6±0.2)×105(2.2\pm 0.6\pm 0.2)\times 10^{-5}, for χc1ϕϕ\chi_{c1}\to \phi\phi, ωω\omega\omega, and ωϕ\omega\phi, respectively. The observation of χc1\chi_{c1} decays into a pair of vector mesons ϕϕ\phi\phi, ωω\omega\omega and ωϕ\omega\phi indicates that the hadron helicity selection rule is significantly violated in χcJ\chi_{cJ} decays. In addition, the measurement of χcJωϕ\chi_{cJ}\to \omega\phi gives the rate of doubly OZI-suppressed decay. Branching fractions for χc0\chi_{c0} and χc2\chi_{c2} decays into other vector meson pairs are also measured with improved precision.Comment: 4 pages, 2 figure

    First Observation of the Decays chi_{cJ} -> pi^0 pi^0 pi^0 pi^0

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    We present a study of the P-wave spin -triplet charmonium chi_{cJ} decays (J=0,1,2) into pi^0 pi^0 pi^0 pi^0. The analysis is based on 106 million \psiprime decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the pi^0 pi^0 pi^0 pi^0 hadronic final state is observed for the first time. We measure the branching fractions B(chi_{c0} -> pi^0 pi^0 pi^0 pi^0)=(3.34 +- 0.06 +- 0.44)*10^{-3}, B(chi_{c1} -> pi^0 pi^0 pi^0 pi^0)=(0.57 +- 0.03 +- 0.08)*10^{-3}, and B(chi_{c2} -> pi^0 pi^0 pi^0 pi^0)=(1.21 +- 0.05 +- 0.16)*10^{-3}, where the uncertainties are statistical and systematical, respectively.Comment: 7 pages, 3 figure

    Study of χcJ\chi_{cJ} radiative decays into a vector meson

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    The decays χcJγV\chi_{cJ}\to\gamma V (V=ϕ,ρ0,ωV=\phi, \rho^0, \omega) are studied with a sample of radiative \psip\to\gamma\chi_{cJ} events in a sample of (1.06\pm0.04)\times 10^{8} \psip events collected with the BESIII detector. The branching fractions are determined to be: B(χc1γϕ)=(25.8±5.2±2.3)×106{\cal B}(\chi_{c1}\to \gamma\phi)=(25.8\pm 5.2\pm 2.3)\times 10^{-6}, B(χc1γρ0)=(228±13±22)×106{\cal B}(\chi_{c1}\to \gamma\rho^0)=(228\pm 13\pm 22)\times 10^{-6}, and B(χc1γω)=(69.7±7.2±6.6)×106{\cal B}(\chi_{c1}\to \gamma\omega)=(69.7\pm 7.2\pm 6.6)\times 10^{-6}. The decay χc1γϕ\chi_{c1}\to \gamma\phi is observed for the first time. Upper limits at the 90% confidence level on the branching fractions for χc0\chi_{c0} and \chict decays into these final states are determined. In addition, the fractions of the transverse polarization component of the vector meson in χc1γV\chi_{c1}\to \gamma V decays are measured to be 0.290.120.09+0.13+0.100.29_{-0.12-0.09}^{+0.13+0.10} for χc1γϕ\chi_{c1}\to \gamma\phi, 0.158±0.0340.014+0.0150.158\pm 0.034^{+0.015}_{-0.014} for χc1γρ0\chi_{c1}\to \gamma\rho^0, and 0.2470.0870.026+0.090+0.0440.247_{-0.087-0.026}^{+0.090+0.044} for χc1γω\chi_{c1}\to \gamma\omega, respectively. The first errors are statistical and the second ones are systematic.Comment: 8 pages, 3 figure

    Multidimensional Scaling Reveals the Main Evolutionary Pathways of Class A G-Protein-Coupled Receptors

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    Class A G-protein-coupled receptors (GPCRs) constitute the largest family of transmembrane receptors in the human genome. Understanding the mechanisms which drove the evolution of such a large family would help understand the specificity of each GPCR sub-family with applications to drug design. To gain evolutionary information on class A GPCRs, we explored their sequence space by metric multidimensional scaling analysis (MDS). Three-dimensional mapping of human sequences shows a non-uniform distribution of GPCRs, organized in clusters that lay along four privileged directions. To interpret these directions, we projected supplementary sequences from different species onto the human space used as a reference. With this technique, we can easily monitor the evolutionary drift of several GPCR sub-families from cnidarians to humans. Results support a model of radiative evolution of class A GPCRs from a central node formed by peptide receptors. The privileged directions obtained from the MDS analysis are interpretable in terms of three main evolutionary pathways related to specific sequence determinants. The first pathway was initiated by a deletion in transmembrane helix 2 (TM2) and led to three sub-families by divergent evolution. The second pathway corresponds to the differentiation of the amine receptors. The third pathway corresponds to parallel evolution of several sub-families in relation with a covarion process involving proline residues in TM2 and TM5. As exemplified with GPCRs, the MDS projection technique is an important tool to compare orthologous sequence sets and to help decipher the mutational events that drove the evolution of protein families
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