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11.
ABSTRACT This paper sets out to trace some major points of convergence between an emerging literature on the political geographies of corruption1 and current attempts to develop a renewed research agenda in the geographies of global finance—in this case in a specifically European context. In particular, we offer some preliminary observations on the need to elaborate an alternative geography of Europe's financial architecture that could incorporate the role of flows of illegal and informal finance as major driving forces behind the way in which that architecture currently constitutes itself. This is an inherently complex task due to the intrinsically hidden nature of these flows and the difficulties involved in their accurate measurement; nevertheless, they are too important to be ignored, as is too frequently the case at present. In the paper we offer some necessarily preliminary, and deliberately provocative, reflections on how to take forward such a re‐conceptualisation. Ultimately, our analysis revolves around the identification of an uneasy tension between the demand for deregulated financial markets and the increasing integration of those markets, and the international momentum towards finding ways of dealing with the (apparently) ever‐increasing problems of corruption, money laundering, and the financing of terrorism through new forms of financial regulation and control.  相似文献   
12.
Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta17O against delta18O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in 17O and 18O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive 16O-rich component of CAIs.  相似文献   
13.
The recently identified plant photoreceptor UVR8 (UV RESISTANCE LOCUS 8) triggers regulatory changes in gene expression in response to ultraviolet-B (UV-B) light through an unknown mechanism. Here, crystallographic and solution structures of the UVR8 homodimer, together with mutagenesis and far-UV circular dichroism spectroscopy, reveal its mechanisms for UV-B perception and signal transduction. β-propeller subunits form a remarkable, tryptophan-dominated, dimer interface stitched together by a complex salt-bridge network. Salt-bridging arginines flank the excitonically coupled cross-dimer tryptophan "pyramid" responsible for UV-B sensing. Photoreception reversibly disrupts salt bridges, triggering dimer dissociation and signal initiation. Mutation of a single tryptophan to phenylalanine retunes the photoreceptor to detect UV-C wavelengths. Our analyses establish how UVR8 functions as a photoreceptor without a prosthetic chromophore to promote plant development and survival in sunlight.  相似文献   
14.
Metalloantibodies   总被引:8,自引:0,他引:8  
A metalloantibody has been constructed with a coordination site for metals in the antigen binding pocket. The Zn(II) binding site from carbonic anhydrase B was used as a model. Three histidine residues have been placed in the light chain complementarity determining regions of a single chain antibody molecule. In contrast to the native protein, the mutant displayed metal-dependent fluorescence-quenching behavior. This response was interpreted as evidence for metal binding in the three-histidine site with relative affinities in the order Cu(II) greater than Zn(II) greater than Cd(II). The presence of metal cofactors in immunoglobulins should facilitate antibody catalysis of redox and hydrolytic reactions.  相似文献   
15.
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