0000000000071304
AUTHOR
Alain Garcia
"Save Private Pinna !" The Mediterranean fan mussel, a patrimonial bivalve, is in serious danger of extinction.
Pinna nobilis is the largest bivalve in the Mediterranean Sea. This endemic species lives in the Posidonia meadows,in the form of small sparse populations. It is a heritage species: its byssus has long been collected to be wovenand used to make gloves, hats or stoles. Protected by a European Directive (1992), P. nobilis is closely monitored,nationally and internationally. But since the end of 2016, an epidemic, which origin seems to be a protozoan parasite,decimates populations (up to 100% mortality). This event began on the Spanish coast and spreads now all around theMediterranean. Although conservation measures have been taken, the next few years could see the extinction of thisemblematic…
Structural study of NaNdGa4S8, a luminescent material with low-concentration quenching
Abstract Single-crystal X-ray diffraction analysis and optical investigations of NaNdGa 4 S 8 show that Nd 3+ ions are essentially distributed in two of the three square antiprismatic sites of a CaGa 2 S 4 -type lattice. The NdS 8 polyhedra are isolated (minimum NdNd distance: 6.07 A) so the interactions responsible for concentration quenching of the luminescence are considerably reduced