High Temperature Ferromagnetism in a GdAg2 Monolayer.

Materials that exhibit ferromagnetism, interfacial stability, and tunability are highly desired for the realization of emerging magnetoelectronic phenomena in heterostructures. Here we present the GdAg2 monolayer alloy, which possesses all such qualities. By combining X-ray absorption, Kerr effect, and angle-resolved photoemission with ab initio calculations, we have investigated the ferromagnetic nature of this class of Gd-based alloys. The Curie temperature can increase from 19 K in GdAu2 to a remarkably high 85 K in GdAg2. We find that the exchange coupling between Gd atoms is barely affected by their full coordination with noble metal atoms, and instead, magnetic coupling is effectively mediated by noble metal-Gd hybrid s,p-d bands. The direct comparison between isostructural GdAu2 and GdAg2 monolayers explains how the higher degree of surface confinement and electron occupation of such hybrid s,p-d bands promote the high Curie temperature in the latter. Finally, the chemical composition and structural robustness of the GdAg2 alloy has been demonstrated by interfacing them with organic semiconductors or magnetic nanodots. These results encourage systematic investigations of rare-earth/noble metal surface alloys and interfaces, in order to exploit them in magnetoelectronic applications.

Psychotropic drug prescription in Italy. A survey in general practice.

A survey of psychotropic drug prescription was conducted in Verona using information obtained from 92 GPs. A total of 2559 patients consulted their GPs on the day of the study and 14.2% of them received a prescription for a psychotropic drug. Benzodiazepines were the most frequently prescribed: 72.8% and 70.4% of all psychotropic prescriptions in women and men respectively. The prevalence of prescription was higher in women than in men (15.8% vs 11.2%) and the difference was statistically significant (P less than 0.001). Subjects aged 45-64 had the highest chance of receiving prescriptions for psychotropics. Occupational status seems related to psychotropic drug prescription only in women. A strong association was found between psychotropic drug prescription and conspicuous psychiatric morbidity. This association was independent of sex, age, and occupational status. An interactive effect between social problems and sex on psychotropic drug prescription was found. The perception by the GP of a social problem increases the risk that a psychotropic will be prescribed about twice in women, but not in men.

Calcitonin serum levels in different pituitary diseases. A preliminary report.

The calcitonin (CT) concentration has been determined in the serum of 17 patients with different pituitary diseases. More or less elevated levels were found in 7 of them. No definite correlation has been observed between the immunoreactive CT and the different pituitary hormones.