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The sensitization of lanthanide complexes in the visible region is of particular interest for practical applications such as labeling, biological analysis and optoelectronics. A visible-light sensitized Er3+complex based on the use of a highly conjugated ß-diketonate (1, 3-di(2-naphthyl)-1, 3-propanedione, Hdnm) and 5-nitro-1, 10-phenanthroline (5NO2phen) as an ancillary ligand, [Er(dnm)3(5NO2phen)], has been synthesized, fully characterized and its photophysical properties have been investigated. Suitably expanded p-conjugation in the complex molecule makes the excitation window red-shifted to the visible region (up to 550 nm). Efficient energy transfer by antenna effect results in 1.53 µm emission from the Er3+ion.

Treatment of heterobimetallic sulfido-bridged complexes Cp(acac)Ti(µ3-S)2(M(cod))2] (M = Rh (1), Ir (2)) with the organic acids CX3COOH (X = F, H) forms the corresponding acetate derivatives Cp(CX3COO)Ti(µ3-S)2(M(cod))2] (X = F, M = Rh (3), Ir (4); X = H, M = Rh (5), M = Ir (6)). While complex 3 was easily isolated, compounds 4-6 establish in solution the corresponding equilibria with the starting complexes 1 and 2. Treatment of 1 with a hydrochloric acid solution in THF generates the heterohexanuclear cationic cluster (CpTi(µ3-S)2(Rh(cod))2)2(µ-OH)]Cl] (7), which is deprotonated with weak bases affording the oxo derivative (CpTi(µ3-S)2(Rh(cod))2)2(µ2-O)] (8). Cluster 8, and the analogous with the ligand methylcyclopentadienyl ((CpMe)Ti(µ3-S)2(Rh(cod))2)2(µ2-O)] (9), can be synthesized from reaction of the respective complexes Cp2Ti(SH)2] and (CpMe)2Ti(SH)2] with the methoxo-bridged dinuclear complex (Rh(µ-OMe)(cod))2] in the presence of water. A preliminary study of the molecular structure of 9 confirmed the formation of an almost linear array of the "Ti-O-Ti" subunit, in which each titanium atom supports two "Rh(cod)" moieties through two sulfido bridges. Further, the heterotetranuclear cluster CpTi(µ3-S)3Ir3(µ2-CO)(CO)3(PMe3)3] (10) reacts with alkynes at the triiridium metallic triangle. The reactions with activated alkynes, such as dimethyl acetylenedicarboxylate (or diethyl acetylenedicarboxylate) afford clusters CpTi(µ3-S)3Ir3(µ2-¿1-RO2CCCCO2R)(C(O)RO2CCCCO2R)(CO)3(PMe3)3] (R = Me (11), Et (12)), which incorporate two molecules of alkyne. The X-ray molecular structure of 11 shows that one alkyne is cis-metallated to the metal-metal bonded iridium centres whereas the other is taking part of a iridacyclobutenone moiety resulting from the CO migratory insertion into a iridium-alkyne bond at the third iridium centre. However, reaction of 10 with phenylacetylene stops at the cluster CpTi(µ3-S)3Ir3(µ2-¿1-PhCCH)(CO)3(PMe3)3] (13), which contains only a cis-metallated olefin to two metal-metal bonded iridium atoms. The X-ray molecular structure of CpTi(µ3-S)3Ir3(µ2-¿1-PhCCH)(H)(CO)3(PMe3)3]BF4] (14), the product resulting from protonation of 13 with HBF4·OEt2 shows that the TiIr3] core remains intact and that the olefin is indeed cis-metallated to the two metal-metal bonded iridium atoms, while the third iridium atom from the metallic triangle becomes protonated.

10th International Conference on Laser Ablation, Singapore, November 22-27, 2009

9th International Conference on Laser Ablation, Tenerife, Spain, September 24-28, 2007

9th International Conference on Laser Ablation, Tenerife, Spain, September 24-28, 2007

We describe the first demonstration of laser action in a dielectric waveguide grown by molecular beam epitaxy. Laser emission at 1.063µm is obtained from a Nd:LaF3 thin film grown on a CaF2 substrate.

Resumen Se presentan 2 casos de neumonia intersticial localizada, uno con un cuadro histologico compatible con una neumonia intersticial descamativa y otro con un patron de neumonia intersticial clasica. Revisando los casos de neumonia intersticial localizada existentes en la literatura se llega a la conclusion de que las formas localizadas constituyen un grupo con unas caracteristicas clinicorradiologicas propias, muy diferentes del de las formas difusas, presentando unas posibilidades terapeuticas mucho mayores que estas ultimas.

Resumen Se presenta el caso de una enferma con infeccion respiratoria por Nocardia caviae , controlada durante mas de un ano, y se comentan aspectos clinicos, radiologicos y terapeuticos de la misma. Creemos es el primer caso publicado en nuestro pais; y el tercero de la literatura.

A fundamental question may be proposed. Does the higher frequency of asthmatic deaths mean an increase in the severity of the asthma? Many authors think it possible. Alexander5 describes three epochs in the evolution of the frequency of these deaths. In the first epoch, the asthma cases were allergic and atopic and were somewhat light, and the observations of fatal cases were rare. In the second one, around 1930, fatal cases became more frequent, due to the fact that the infectious type was added. (These latter cases, even though having a similar symptomatology, are somewhat more severe and the asthma lasts longer; they very easily evolve toward fatal complications.) Finally, in a third epoch from 1953 up to the present time, again the frequency of fatal cases has decreased, possibly due to the use of the adrenal corticoids, ACTH, antibiotics, and other therapies. The evolution of these three epochs looks somewhat doubtful to us but it is so evident that the frequency of death among patients with an "asthmoid" background has increased. We have gathered, at our clinic, 33 fatal cases out of which three were observed from 1940 to 1954, and the other 30 have been observed in the last ten years, among 2,225 (1.3%) asthmatic patients. A review of the latter cases, searching the possible causes of differences between fatal and non-fatal termination, shows two factors. In the first place, it is a matter of different types which have been considered jointly, due to the common presence of respiratory dyspnea, which may have seasons of varying intensity, and which also respond, more or less speedily, to the comparable therapy (adrenalin, Isuprel, Euphiline, glucocorticoids) . In the second place, in the serious cases we now have many therapeutic measures which require hospitalization (aspiration, controlled respiration, etc.) This makes it possible that more and * This paper was submitted as part of the M. M. Peshkin Commemorative Volume.

In dichloromethane under reflux, the five-coordinate alkenyl complexes [Rh(acac){(E)-CHCHR}(PCy3)2]BF4 [R=Cy (1), Ph (2), H (3)] evolve into the alkenylphosphonium derivatives [Rh(acac){η2-(E)-CH(PCy3)CHR}(PCy3)]BF4 [R=Cy (4), Ph (5), H(6)], by reductive elimination reactions involving the one-electron alkenyl fragments and one of the two-electron phosphine ligands of 1–3. Complexes 4–6 react with carbon monoxide to afford Rh(acac)(CO)(PCy3) and [(E)-RHCCHPCy3]BF4 [R=Cy (8), Ph (9), H (10)]. In addition, we describe a new route for the preparation of alkenylphophonium salts starting from terminal alkynes, PCy3 and HBF4, and using the Rh(acac)(PCy3) unit as a template., We thank the DGICYT (Projects PB 94-1186 and PB 95-0806, Programa de Promoción General del Conocimiento) for financial support. A. Martı́nez is grateful for the F.P.I. grant (M.E.C.).