Ti-Doped Sapphire (Al(2)O(3)) Single Crystals Grown by the Kyropoulos Technique and Optical Characterizations.

International audienceTransparent high optical quality and large Ti-sapphire (Ti(3+)-doped Al(2)O(3)) single crystals have been grown by the Kyropoulos technique (KT) for optical amplification. The present work shows that by the utilization of KT growth technology and the optimization of the growth conditions it is possible to grow Ti-doped Al(2)O(3), 100 mm in diameter and 5 kg in weight. We have demonstrated that large Ti(0.25 atom %)-doped Al(2)O(3) crystals show high chemical homogeneities and good optical properties and amplify the energy without any special annealing. Ti-doped sapphire crystals are for high power laser applications and particularly for the shortest pulses ever produced from a laser oscillator

Symbiosis-related plant genes modulate molecular responses in an arbuscular mycorrhizal fungus during early root interactions

International audienceTo gain further insight into the role of the plant genome in arbuscular mycorrhiza (AM) establishment, we investigated whether symbiosis-related plant genes affect fungal gene expression in germinating spores and at the appressoria stage of root interactions. Glomus intraradices genes were identified in expressed sequence tag libraries of mycorrhizal Medicago truncatula roots by in silico expression analyses. Transcripts of a subset of genes, with predicted functions in transcription, protein synthesis, primary or secondary metabolism, or of unknown function, were monitored in spores and germinating spores and during interactions with roots of wild-type or mycorrhiza-defective (Myc–) mutants of M. truncatula. Not all the fungal genes were active in quiescent spores but all were expressed when G. intraradices spores germinated in wild-type M. truncatula root exudates or when appressoria or arbuscules were formed in association with wild-type M. truncatula roots. Most of the fungal genes were upregulated or induced at the stage of appressorium development. Inactivation of the M. truncatula genes DMI1, DMI2/MtSYM2, or DMI3/MtSYM13 was associated with altered fungal gene expression (nonactivation or inhibition), modified appressorium structure, and plant cell wall responses, providing first evidence that cell processes modified by symbiosis-related plant genes impact on root interactions by directly modulating AM fungal activity

EMSO-Açores. Valorisation de l‘infrastructure et de la série de campagnes MoMARSAT 2010-2020

Ce document présente les activités de valorisation de l‘infrastructure EMSO-Açores et de la série de campagnes MoMARSAT entre 2010-2020. La série de campagnes MoMARSAT assure la maintenance annuelle de l'observatoire EMSO-Açores sur le champ hydrothermal Lucky Strike (https://doi.org/10.18142/130). Cet observatoire fond de mer est opéré depuis 2010 et vise à acquérir des séries temporelles ≥10 ans sur les processus hydrothermaux, tectoniques, volcaniques et les écosystèmes d'un site hydrothermal actif de la dorsale médio-Atlantique. Il fait partie du réseau européen EMSO (European Multidisciplinary Seafloor and water column Observatory-ERIC - http://emso.eu/), soutenu en France par l'Infrastructure de Recherche (MESR) EMSO-FR dont le pilotage est assuré par une collaboration Ifremer-CNRS