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Rapid Exchange (rapid + exchange)
Selected AbstractsThe "End of Geography" in Financial Services?ECONOMIC GEOGRAPHY, Issue 4 2000Local Embeddedness, Territorialization in the Interest Rate Swaps Industry Abstract: This paper provides evidence that the globalization of financial services has not undermined the importance of local embeddedness in world financial centers, among global banks. Using qualitative data from interviews with senior bankers in the interest rate swaps (derivatives) industry in Australia, in this paper I demonstrate the importance of spatial relationships and processes of local embeddedness in the production of swaps. Local embeddedness is attributable to the rapid exchange of financial information in formal dealing networks that serve as central information sources, enabling dealers to formulate a "market feel" that influences their dealing strategies. Information interpretation and decision making in dealing processes and specialist financial labor provide the foundations for the product-based learning orientation of swaps dealing. Dealing networks are underpinned by social relationships, requiring face-to-face interaction that is facilitated by spatial proximity. Although the global swaps industry is dominated by multinational banks, the centrality of these embedded networks impedes globalization in interest rate swaps dealing. The global swaps industry comprises an international network of highly localized but interconnected operations based in world financial centers. [source] Syntheses and Fluxional Processes of Diphenyl(2-thienyl)phosphane Derivatives of Triosmium ClustersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2006Nitsa K. Kiriakidou Kazemifar Abstract Thermal treatment of [Os3(CO)12] with diphenyl(2-thienyl)phosphane, Ph2P(C4H3S), results in the formation of [Os3(CO)12,x{Ph2P(C4H3S)}x] (x = 1,3, 1,3), but no C,H bond activation was observed. Reaction of [H2Os3(CO)10] with diphenyl(2-thienyl)phosphane at ambient temperature affords [HOs3(,-H)(CO)10{Ph2P(C4H3S)}] (4), but when the samereaction is repeated at elevated temperatures, the cyclometallated species [(,-H)Os3(CO)9{,3 -Ph2P(C4H2S)}] (5) and[(,-H)Os3(CO)8{,3 -Ph2P(C4H2S)}{Ph2P(C4H3S)}] (6) are formed. In addition, two more products, tentatively assigned as [(,-H)Os3(CO)6{,3 -Ph2P(C4H2S)}{,-Ph2P(C4H3S)}{Ph2P(C4H3S)}] (7) and [(,-H)Os3(CO)7{,-Ph2P(C4H2S)}{,-Ph2P(C4H3S)}{Ph2P(C4H3S)}] (8) are obtained. The dynamic behaviours of 2, 5 and 6 have been studied by variable-temperature (VT) 1H and 31P{1H} NMR spectroscopy. The VT 31P{1H} NMR spectra of [Os3(CO)10{Ph2P(C4H3S)}2] (2) demonstrate that a mixture of two isomers, which are in rapid exchange at room temperature, is present and that the less common cis - trans isomer, whose structure has been determined by X-ray crystallography, is favoured for this cluster. The VT 1H NMR spectra of 5 indicate the presence of two isomers which are proposed to arise from an oscillation of the ,,,2 -vinyl group of the thienyl moiety between two metal atoms. A similar fluxional process is proposed to occur in 6 and the assignment of the room-temperature structure(s) of this cluster was confirmed by 1H- 187Os 2D HMQC spectroscopy. In addition to 2, the solid-state structures of 3, 5 and 6 have been determined by X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Functional Analysis of Prokaryotic SELB proteinsBIOFACTORS, Issue 1-4 2001Martin Thanbichler Abstract Since the discovery of selenocysteine as the 21st amino acid considerable progress has been made in elucidating the system responsible for its insertion into proteins. Elongation factor SELB, whose amino-terminal part shows homology to EF-Tu, was found to be the key component mediating delivery of selenocysteyl-tRNASec to the ribosomal A site. It exhibits a distinct tertiary structure comprising binding sites for guanosine nucleotides, the cognate tRNA, an mRNA secondary structure (SECIS element) and presumably ribosomal components. The kinetics of interaction of SELB with its ligands have been studied in detail. GDP was found to bind with about 20-fold lower affinity than GTP and to be in rapid exchange, which obviates the need for a guanosine nucleotide exchange factor. The affinity of SELB for the SECIS element is in the range of 1 nM and further increases upon binding of selenocysteyl-tRNASec to the protein. This supports the model that SELB forms a tight quaternary complex on the SECIS element which is loosened after insertion of the tRNA into the ribosomal A site and the concomitant hydrolysis of GTP. [source] The effects of the cyclosporin A, a P-glycoprotein inhibitor, on the pharmacokinetics of baicalein in the rat: a microdialysis studyBRITISH JOURNAL OF PHARMACOLOGY, Issue 8 2002T H Tsai Baicalein is a bioactive flavonoid isolated from the root of Scutellaria baicalensis Georgi, a medicinal herb that has been used since ancient times to treat bacterial infections. As little is known concerning its pharmacokinetics, this study focussed on its pharmacokinetics as well as the possible roles of the multidrug transporter P-glycoprotein on its distribution and disposition. Three microdialysis probes were simultaneously inserted into the jugular vein, the hippocampus and the bile duct of male Sprague,Dawley rats for sampling in biological fluids following the administration of baicalein (10, 30 and 60 mg kg,1) through the femoral vein. The P-glycoprotein inhibitor cyclosporin A was used to help delineate its roles. The study design consisted of two groups of six rats in parallel: control rats which received baicalein alone and the cyclosporin A treated-group in which the rats were injected cyclosporin A, a P-glycoprotein inhibitor, 10 min prior to baicalein administration. Cyclosporin A treatment resulted in a significant increase in elimination half-life, mean residence time and area under the concentration versus time curve (AUC) of unbound baicalein in the brain. However, AUC in the bile was decreased. The decline of baicalein in the hippocampus, blood and bile suggested that there was rapid exchange and equilibration between the peripheral compartment and the central nervous system. In addition, the results indicated that baicalein was able to penetrate the blood,brain barrier as well as undergoing hepatobiliary excretion. Although no direct transport studies were undertaken and multiple factors may affect BBB penetration and hepatobiliary excretion, strong association of the involvement of P-glycoprotein in these processes is indicated. British Journal of Pharmacology (2002) 137, 1314,1320. doi:10.1038/sj.bjp.0704959 [source] Selective Binding of Imidazolium Cations in Building Multi-Component LayersCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2010Irene Ling Abstract Addition of 1-alkyl-3-methylimidazolium (Cn -mim) cations 3,5 to a mixture of bis-phosphonium cation 2 and sodium p -sulfonatocalix[4]arene (1) in the presence of lanthanide ions results in the selective binding of an imidazolium cation into the cavity of the calixarene. The result is a multi-layered solid material with an inherently flexible interplay of the components. Incorporating ethyl-, n -butyl- or n -hexyl-mim cations into the multi-layers results in significant perturbation of the structure, the most striking effect is the tilting of the plane of the bowl-shaped calixarene relative to the plane of the multi-layer, with tilt angles of 7.2, 28.9 and 65.5°, respectively. The lanthanide ions facilitate complexation, but are not incorporated into the structures and, in all cases, the calixarene takes on a 5, charge, with one of the lower-rim phenolic groups deprotonated. ROESY NMR experiments and other 1H,NMR spectroscopy studies establish the formation of 1:1 supermolecules of Cn -mim and calixarene, regardless of the ratio of the two components, and indicate that the supermolecules undergo rapid exchange on the NMR spectroscopy timescale. [source] On the Scope of Trimethylaluminium-Promoted 1,2-Additions of ArZnX Reagents to AldehydesCHEMISTRY - A EUROPEAN JOURNAL, Issue 3 2010Daniel Glynn Abstract A practical asymmetric 1,2-addition of functionalised arylzinc halides to aromatic and aliphatic aldehydes is described by the use of aminoalcohol catalysis in the presence of AlMe3. The process is simple to carry out, uses only commercially available reagents/ligands and provides moderate to good (80,96,% ee) enantioselectivities for a wide range of substrates. Either commercial ArZnX reagents or those prepared in situ from low cost aryl bromides can be used. In the latter case electrophilic functional groups are tolerated (CO2Et, CN). The reaction relies on rapid exchange between ArZnX and AlMe3 to generate mixed organometallic species that lead to the formation of a key intermediate that is distinctly different from the classic "anti" transition states of Noyori. NMR monitoring and related experiments have been used to probe the validity of the proposed selective transition state. [source] | ||||||||||