SALMONID WHIRLING DISEASE

Salmonid whirling disease-sometimes referred to as blacktail -is a chronic, noncontagious parasitic infection of trout and, to a lesser extent, other members of the family Salmonidae. The parasite has specific tropism for cartilage. If the infection is heavy and the fish is young, mortality sometimes results. More commonly, the parasitosis evokes abnormal swimming behavior and the transient melanism of the caudal fin and peduncle that is the blacktail sign (Fig. 1). When the parasite is given sufficient time for development and the infection is sufficiently intense, the head and axial skeleton become disfigured in some vIictims (Fig. 2). However, the behavior and appearance of lightly infected fish are commonly normal, or nearly so (Fig. 3). The parasite belongs to the group of protozoans known as myxosporeans. Although it was first encountered in Europe at the turn of the century, its life cycle was not discovered until the early 1980\u27s. During the intervening years, methods of diagnosis, detection, and identification were developed and improved

Mably – Zac de Bonvert (tranche 1)

La première phase de terrain de cette fouille archéologique s’est déroulée sur quatre mois entre février et juin 2014, sur une surface de 10 500 m2. Le lieu-dit Bonvert, située en périphérie reculée de l’agglomération de Roanne/Rodumna, est circonscrit dans un secteur qui a depuis longtemps montré de nombreux indices d’occupation d’époque protohistorique et gallo-romaine. Dans l’attente des résultats des études en cours, le site de la Zac de Bonvert constitue d’ores et déjà un témoignage uniq..

Multi-core fibre-fed integral-field unit (MCIFU):Overview and first-light

The Multi-Core Integral-Field Unit (MCIFU) is a new diffraction-limited near-infrared integral-field unit for exoplanet atmosphere characterization with extreme adaptive optics (xAO) instruments. It has been developed as an experimental pathfinder for spectroscopic upgrades for SPHERE+/VLT and other xAO systems. The wavelength range covers 1.0 um to 1.6um at a resolving power around 5000 for 73 points on-sky. The MCIFU uses novel astrophotonic components to make this very compact and robust spectrograph. We performed the first successful on-sky test with CANARY at the 4.2 meter William Herschel Telescope in July 2019, where observed standard stars and several stellar binaries. An improved version of the MCIFU will be used with MagAO-X, the new extreme adaptive optics system at the 6.5 meter Magellan Clay telescope in Chile. We will show and discuss the first-light performance and operations of the MCIFU at CANARY and discuss the integration of the MCIFU with MagAO-X.</p

Le site antique de Bonvert à Mably (42) : bilan critique des témoignages archéologiques

International audienc

Une ferme gauloise et une officine de potier du Ier s. apr. J.-C. dans la plaine de roanne (42)

International audienc

Une ferme gauloise et une officine de potier du Ier s. apr. J.-C. dans la plaine de roanne (42)

International audienc

Le site de Bonvert à Mably (Loire) entre la fin du Ier Âge du fer et le second moyen-Âge

International audienc

Le site de Bonvert à Mably (Loire) entre la fin du Ier Âge du fer et le second moyen-Âge

International audienc