98 research outputs found
Global General Circulation of the Ocean Estimated by the ECCO-Consortium
Following on the heels of the World Ocean Circulation
Experiment, the Estimating the Circulation and Climate of the Ocean (ECCO)
consortium has been directed at making the best possible estimates of ocean
circulation and its role in climate. ECCO is combining state-of-the-art ocean
general circulation models with the nearly complete global ocean data sets for
1992 to present. Solutions are now available that adequately fit almost all types
of ocean observations and that are, simultaneously, consistent with the model.
These solutions are being applied to understanding ocean variability, biological
cycles, coastal physics, geodesy, and many other areas.National Oceanographic Partnership Program (U.S.)United States. National Aeronautics and Space AdministrationNational Science Foundation (U.S.)United States. National Oceanic and Atmospheric AdministrationNational Center for Atmospheric Research (U.S.)San Diego Supercomputer CenterGeophysical Fluid Dynamics Laboratory (U.S.)Jet Propulsion Laboratory (U.S.)
An influenza A virus can evolve to use human ANP32E through altering polymerase dimerization
Human ANP32A and ANP32B are essential but redundant host factors for influenza virus genome replication. While most influenza viruses cannot replicate in edited human cells lacking both ANP32A and ANP32B, some strains exhibit limited growth. Here, we experimentally evolve such an influenza A virus in these edited cells and unexpectedly, after 2 passages, we observe robust viral growth. We find two mutations in different subunits of the influenza polymerase that enable the mutant virus to use a novel host factor, ANP32E, an alternative family member, which is unable to support the wild type polymerase. Both mutations reside in the symmetric dimer interface between two polymerase complexes and reduce polymerase dimerization. These mutations have previously been identified as adapting influenza viruses to mice. Indeed, the evolved virus gains the ability to use suboptimal mouse ANP32 proteins and becomes more virulent in mice. We identify further mutations in the symmetric dimer interface which we predict allow influenza to adapt to use suboptimal ANP32 proteins through a similar mechanism. Overall, our results suggest a balance between asymmetric and symmetric dimers of influenza virus polymerase that is influenced by the interaction between polymerase and ANP32 host proteins
Sarcocystis Species Lethal for Domestic Pigeons
A large number of Sarcocystis spp. infect birds as intermediate hosts, but pigeons are rarely affected. We identified a novel Sarcocystis sp. that causes lethal neurologic disease in domestic pigeons in Germany. Experimental infections indicated transmission by northern goshawks, and sequence analyses indicated transnational distribution. Worldwide spread is possible
The Clacton Spear: the last one hundred years
In 1911 an eminent amateur prehistorian pulled the broken end of a pointed wooden shaft from Palaeolithic-age sediments at a seaside town in Essex. This artefact, still the earliest worked wood to be discovered in the world, became known as the Clacton Spear. Over the past 100 years it has variously been interpreted as a projectile weapon, a stave, a digging stick, a snow probe, a lance, a game stake and a prod to ward off rival scavengers. These perspectives have followed academic fashions, as the popular views of early hominins have altered. Since discovery the Clacton spear has also been replicated twice, has undergone physical transformations due to preservation treatments, and has featured in two public exhibitions. Within this article the changing context of the spear, its parallels, and all previous conservation treatments and their impacts are assessed.© 2015 Royal Archaeological Institute. This is an Accepted Manuscript of an article published by Taylor & Francis in The Archaeological Journal on 3rd March 2015, available online: http://www.tandfonline.com/doi.org/10.1080/00665983.2015.1008839.The attached document is the author(’s’) final accepted/submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it
Depicting the tree of life: The philosophical and historical roots of evolutionary tree diagrams
info:eu-repo/semantics/publishedVersio
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