10 research outputs found

    Evaluating the Temporal and the Spatial Heterogeneity of the European Convergence Process, 1980-1999

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    In this paper, we suggest a general framework that allows testing simultaneously for temporal heterogeneity, spatial heterogeneity and spatial autocorrelation in b-convergence models. Based on a sample of 145 European regions over the 1980-1999 period, we estimate a Seemingly Unrelated Regression Model with spatial regimes and spatial autocorrelation for two sub-periods: 1980-1989 and 1989-1999. The assumption of temporal independence between the two-periods is rejected and the estimation results point to the presence of spatial error autocorrelation in both sub-periods and spatial instability in the second sub-period, indicating the formation of a convergence club between the peripheral regions of the European Union.b-convergence models, spatial autocorrelation, convergence clubs, temporal instability

    HIV-1 uses dynamic capsid pores to import nucleotides and fuel encapsidated DNA synthesis

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    © 2016 Macmillan Publishers Limited. All rights reserved. During the early stages of infection, the HIV-1 capsid protects viral components from cytosolic sensors and nucleases such as cGAS and TREX, respectively, while allowing access to nucleotides for efficient reverse transcription. Here we show that each capsid hexamer has a size-selective pore bound by a ring of six arginine residues and a â molecular iris' formed by the amino-terminal β-hairpin. The arginine ring creates a strongly positively charged channel that recruits the four nucleotides with on-rates that approach diffusion limits. Progressive removal of pore arginines results in a dose-dependent and concomitant decrease in nucleotide affinity, reverse transcription and infectivity. This positively charged channel is universally conserved in lentiviral capsids despite the fact that it is strongly destabilizing without nucleotides to counteract charge repulsion. We also describe a channel inhibitor, hexacarboxybenzene, which competes for nucleotide binding and efficiently blocks encapsidated reverse transcription, demonstrating the tractability of the pore as a novel drug target
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