Managing cultural and natural heritage : strategic perspectives for Latin America and the Caribbean

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Beta Cell Hubs Dictate Pancreatic Islet Responses to Glucose

N.R.J. was supported by a Diabetes UK RW and JM Collins Studentship (12/0004601). J.B. was supported by a European Foundation for the Study of Diabetes (EFSD) Albert Renold Young Scientist Fellowship and a Studienstiftung des deutschen Volkes PhD Studentship. D.T. was supported by an Advanced Grant from the European Research Commission (268795). G.A.R. was supported by Wellcome Trust Senior Investigator (WT098424AIA) and Royal Society Wolfson Research Merit Awards, and by MRC Programme (MR/J0003042/1), Biological and Biotechnology Research Council (BB/J015873/1), and Diabetes UK Project (11/0004210) grants. G.A.R. and M.W. acknowledge COST Action TD1304 Zinc-Net. D.J.H. was supported by Diabetes UK R.D. Lawrence (12/0004431), EFSD/Novo Nordisk Rising Star and Birmingham Fellowships, a Wellcome Trust Institutional Support Award, and an MRC Project Grant (MR/N00275X/1) with G.A.R. D.J.H and G.A.R. were supported by Imperial Confidence in Concept (ICiC) Grants. J.F. was supported by an MRC Programme grant (MR/L02036X/1). L.P. provided human islets through collaboration with the Diabetes Research Institute, IRCCS San Raffaele Scientific Institute (Milan), within the European islet distribution program for basic research supported by JDRF (1-RSC-2014-90-I-X). P.M. and M.B. were supported by the Innovative Medicine Initiative Joint Undertaking under grant agreement no. 155005 (IMIDIA), resources of which are composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013) and EFPIA companies in kind contribution, and by the Italian Ministry of University and Research (PRIN 2010-2012). D.B. and E.B. provided human islets through the European Consortium for Islet Transplantation sponsored by JDRF (1-RSC-2014-100-I-X)

Effect of magnetic field on the decay kinetics of triplet luminescence of the self-trapped exciton perturbed by Tl+ ion in thallium-doped cesium halides.

Decay kinetics of visible emission of thallium centre in CsCl:Tl, CsBr:Tl and CsI:TI crystals is studied in the magnetic field B // [001] at 0.35-0.45 K. Our previous interpretation of this emission as the triplet luminescence of the self-trapped exciton perturbed by Tl+ ion is confirmed. However, the detailed structure of the corresponding relaxed excited state is found to be much more complicated than that concluded before

Relaxed excited state structure and luminescence of thallium-doped caesium chloride and bromide.

Four bands, all belonging to the main thallium centres, have been detected in the emission spectra of CsCl:Tl and CsBr:Tl crystals. Their spectral, polarization and kinetic characteristics have been studied from 0.45 up to 360 K. It has been shown that the new model proposed by us recently for the relaxed excited state (RES) structure of the luminescence centre in CsI:Tl crystals is valid for CsCl:Tl and CsBr:Tl crystals as well. Two ultraviolet emission bands excited mainly in the A absorption band of Tl+ centres are ascribed to electronic transitions from trigonal and tetragonal Jahn-Teller minima of the tripler RES of Tl+. Two visible bands excitable mainly in the higher energy absorption bands of CsCl:Tl and CsBr:Tl are connected with two different off-centre configurations of self-trapped exciton perturbed by the Tl+ ion. The parameters of the corresponding excited state minima have been calculated. The mixing of the impurity and halogen excited states has been shown to decrease markedly in the sequence of anions I- --> Br- --> Cl-

Peculiarities of the triplet relaxed excited state structure in thallium-doped cesium halide crystals.

Four bands, all belonging to the main thallium centre, are detected in the tripler luminescence spectrum of thallium-doped cesium halides under excitation in impurity absorption bands. Their spectral, polarization and kinetics characteristics are studied at 0.35 to 360 K. The parameters of the corresponding relaxed excited states (RES) minima are calculated. Two ultraviolet emission bands are ascribed to electronic transitions from trigonal and tetragonal Jahn-Teller minima of the triplet RES of Tl+ ion. Two visible bands are assumed to arise from two different off-centre configurations of a self-trapped exciton perturbed by Tl+ ion

Peculiarities of the triplet relaxed excited-state structure and luminescence of a CsI:Tl crystal

Four emission bands, all belonging to the main thallium centres, have been detected in CsI:Tl, and their spectral, polarization and kinetic characteristics have been studied at 0.35-320 K. A new model is proposed for the excited states responsible for the luminescence of thallium-doped caesium iodide. In this model, the main thallium centre is considered as a cluster consisting of a Tl+ ion and at least 12 I- and 11 Cs+ ions. Two weak ultraviolet emission bands of CsI:TI (3,31 and 3.09 eV) are ascribed to electronic transitions from trigonal and tetragonal Jahn-Teller minima of the tripler relaxed excited state, whose structure is similar to that of Tl+ centres in Fee alkali halides. Two intense visible bands (2.55 and 2.25 eV) are assumed to arise from two different ('weak' and 'strong') off-centre configurations of a self-trapped exciton perturbed by the Tl+ ion. The minima responsible for all the emission bands are located on the same adiabatic potential energy surface. The excitonic-like nature of visible emission could explain the high scintillation efficiency of CsI:Tl

Luminescence and decay kinetics of relaxed bound excitons and impurity states in CsX:Tl+ (X=Cl, Br, I).

Luminescence, decay kinetics and polarization properties of single Tl+-based centres in CsX hosts (X = Cl, Dr, I) are described in a wide temperature interval 0.3 - 400 K. It is shown that four emission bands co-existing at the same relaxed excited state surface belong to this centre. At sufficiently high temperatures all the relaxed excited state minima are mutually connected by the thermally stimulated transitions