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An outbreak of dengue-like syndrome occurred in Toamasina from January through March 2006. Dengue type l or chikungunya viruses were detected in 38 of 55 patients sampled. Aedes albopictus was the only potential vector collected. Of 4,242 randomly selected representative residents interviewed retrospectively, 67.5% reported a dengue-like syndrome during this period.

We report here a unique example of an in situ generated aluminum initiator stabilized by a C-symmetric salen ligand which shows a hitherto unknown high activity for the ROP of rac-lactide at room temperature. Using a simple and robust catalyst system, which is prepared from a salen complex and an onium salt, this convenient route employs readily available reagents that afford polylactide in good yields with narrow polydispersity indices, without the need for time-consuming and expensive processes that are typically required for catalyst preparation and purification. In line with the experimental evidence, DFT studies reveal that initiation and propagation proceed via an external alkoxide attack on the coordinated monomer.

Cobalt and cobalt−nickel nanoparticles were synthesized by reducing mixtures of cobalt and nickel acetates in sodium hydroxide solution in 1,2-propanediol. The particle shape depends strongly on the sodium hydroxide concentration and the Co/Ni composition of the particles. For cobalt-rich content, agglomerated rods, nanowires with a mean diameter of about 8 nm, and platelets were successively observed when [NaOH] was increased in the range 0−0.2 M. For the Co50Ni50 composition and [NaOH] in the range 0.1−0.18 M, nanodumbbells are formed that consist of a central column richer in cobalt capped with two terminal platelets richer in nickel. The shape of the dumbbells strongly depends on the basicity; long dumbbells are obtained for the lowest NaOH concentration, and short dumbbells and diabolos for the highest. To understand the role of the sodium hydroxide concentration and the different reactivities of cobalt and nickel, we analyzed the equilibrium between the Co2+ and Ni2+ ions in solution and the intermediate unreduced solid phase. For the Co80Ni20 composition, we show that increasing the sodium hydroxide amount lowers the Co2+ and Ni2+ ions in solution through the precipitation of the intermediate solid phase, suggesting that the nanowires are obtained with a higher growth rate than the platelets. The analysis of the solid intermediate phases revealed a Co(II) alkoxide and a Ni(II) hydroxy-acetate showing strong differences in the chemistry of the these two ions in basic solutions of 1,2-propanediol. These differences can explain the two well-separated growth steps originating the Co50Ni50 nanodumbbells.

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A flexible approach towards substituted β- and γ-carbolines based on transition metal catalysed [2+2+2] cycloaddition reactions between functionalised yne-ynamides and methylcyanoformate is described. The versatility of this new reaction sequence is demonstrated by its application in the total synthesis of the marine natural product eudistomin U.