The Challenge of Public Diplomacy for the European External Action Service. EIPAscope 01/2011

One of the main questions emerging from the EU nascent diplomatic corps – the European External Action Service (EEAS) – is what type of diplomacy the EU will conduct and what will be the added value of this new level of diplomacy for the years to come? This article looks at the concept of public diplomacy both in general and in the specific context of EU external relations. It considers the potential of the Lisbon Treaty and the establishment of the EEAS to improve the public diplomacy capacity of the EU and argues that effective EU public diplomacy could be essential to the success of the new European level diplomacy1

Measurement of the energy spectra of primary cosmic ray protons and alpha particles

Imperial Users onl

A fast and robust numerical scheme for solving models of charge carrier transport and ion vacancy motion in perovskite solar cells

Drift-diffusion models that account for the motion of both electronic and ionic charges are important tools for explaining the hysteretic behaviour and guiding the development of metal halide perovskite solar cells. Furnishing numerical solutions to such models for realistic operating conditions is challenging owing to the extreme values of some of the parameters. In particular, those characterising (i) the short Debye lengths (giving rise to rapid changes in the solutions across narrow layers), (ii) the relatively large potential differences across devices and (iii) the disparity in timescales between the motion of the electronic and ionic species give rise to significant stiffness. We present a finite difference scheme with an adaptive time step that is posed on a non-uniform staggered grid that provides second order accuracy in the mesh spacing. The method is able to cope with the stiffness of the system for realistic parameters values whilst providing high accuracy and maintaining modest computational costs. For example, a transient sweep of a current-voltage curve can be computed in only a few minutes on a standard desktop computer.Comment: 22 pages, 8 figure

Physiography and geology of south-central Kansas

Dissertation (Ph.D.)--University of Kansas, Geology, 1934

The Coding Loci of Evolution and Domestication: Current Knowledge and Implications for Bio-Inspired Genome Editing

International audienceOne promising application of CRISPR/Cas9 is to create targeted mutations to introduce traits of interest into domesticated organisms. However, a major current limitation for crop and livestock improvement is to identify the precise genes and genetic changes that must be engineered to obtain traits of interest. Here we discuss the advantages of bio-inspired genome editing, i.e. the engineered introduction of natural mutations that have already been associated with traits of interest in other lineages (breeds, populations, or species). To get a landscape view of potential targets for genome editing, we used Gephebase (www.gephebase.org), a manually-curated database compiling published data about the genes responsible for evolutionary and domesticated changes across Eukaryotes, and examined the >1,200 mutations that have been identified in the coding regions of more than 700 genes in animals, plants and yeasts. We observe that our genetic knowledge is relatively important for certain traits, such as xenobiotic resistance, and poor for others. We also note that protein-null alleles, often due to nonsense and frameshift mutations, represent a large fraction of the known loci of domestication (42% of identified coding mutations), compared to intraspecific (27%) and interspecific evolution (11%). While this trend may be subject to detection, publication, and curation biases, it is consistent with the idea that breeders have selected large-effect mutations underlying adaptive traits in specific settings, but that these mutations and associated phenotypes would not survive the vagaries of changing external and internal environments. Our compilation of the loci of evolution and domestication uncovers interesting options for bio-inspired and transgene-free genome editing

Systematic derivation of a surface polarization model for planar perovskite solar cells

Increasing evidence suggests that the presence of mobile ions in perovskite solar cells can cause a current-voltage curve hysteresis. Steady state and transient current-voltage characteristics of a planar metal halide CH$_3$NH$_3$PbI$_3$ perovskite solar cell are analysed with a drift-diffusion model that accounts for both charge transport and ion vacancy motion. The high ion vacancy density within the perovskite layer gives rise to narrow Debye layers (typical width $\sim$2nm), adjacent to the interfaces with the transport layers, over which large drops in the electric potential occur and in which significant charge is stored. Large disparities between (I) the width of the Debye layers and that of the perovskite layer ($\sim$600nm) and (II) the ion vacancy density and the charge carrier densities motivate an asymptotic approach to solving the model, while the stiffness of the equations renders standard solution methods unreliable. We derive a simplified surface polarisation model in which the slow ion dynamic are replaced by interfacial (nonlinear) capacitances at the perovskite interfaces. Favourable comparison is made between the results of the asymptotic approach and numerical solutions for a realistic cell over a wide range of operating conditions of practical interest.Comment: 32 pages, 7 figure