RESUMEN
The Miocene was a key time in the evolution of African ecosystems witnessing the origin of the African apes and the isolation of eastern coastal forests through an expanding arid corridor. Until recently, however, Miocene sites from the southeastern regions of the continent were unknown. Here, we report the first Miocene fossil teeth from the shoulders of the Urema Rift in Gorongosa National Park, Mozambique. We provide the first 1) radiometric ages of the Mazamba Formation, 2) reconstructions of paleovegetation in the region based on pedogenic carbonates and fossil wood, and 3) descriptions of fossil teeth. Gorongosa is unique in the East African Rift in combining marine invertebrates, marine vertebrates, reptiles, terrestrial mammals, and fossil woods in coastal paleoenvironments. The Gorongosa fossil sites offer the first evidence of woodlands and forests on the coastal margins of southeastern Africa during the Miocene, and an exceptional assemblage of fossils including new species.
RESUMEN
It is established that amphiphilic beta-cyclodextrins chemically modified with alkyl chains on the secondary face exhibit self-organisation properties yielding stable nanospheres or nanoparticles. The ability of these promising colloidal drug carriers to encapsulate drugs being partly related to the internal structure of nanosystems, precise characterisation methods are required to control their synthesis procedure. The present work describes the development of complementary analytical methods based on reversed-phase high-performance liquid chromatography (RPLC) coupled to evaporative light-scattering detection (ELSD) and electrospray ionisation-mass spectrometry (ESI-MS) to characterize various beta-cyclodextrins enzymatically transesterified by vinyl-acyl fatty esters (the number of carbon atom in the acyl chain varying from 4 to 12). LC-ELSD has been used in a preliminary step to optimize the separation on a monolithic octadecylsiloxane-bonded silica stationary phase. A complex fingerprint was achieved for each mixture, revealing the presence of isomers unnoticed by the sole spectrometric (NMR and MS) techniques.
