Reversible ferromagnetic switching in ZnO:(Co,Mn) powders

We report here on the magnetic properties of ZnO:Mn- and ZnO:Co-doped nanoparticles. We have found that the ferromagnetism of ZnO:Mn can be switched on and off by consecutive low-temperature annealings in O2 and N2, respectively, while the opposite phenomenology was observed for ZnO:Co. These results suggest that different defects (presumably n-type for ZnO:Co and p-type for ZnO:Mn) are required to induce a ferromagnetic coupling in each case. We will argue that ferromagnetism is likely to be restricted to a very thin, nanometric layer at the grain surface. These findings reveal and give insight into the dramatic relevance of surface effects to the occurrence of ferromagnetism in ZnO-doped oxides

APLICACIÓN DA ANÁLISE CUSTO-BENEFICIO PARA A AVALIACIÓN EX-POST DA POLÍTICA PÚBLICA AGRARIA: INTERVENCIÓNS DOS FONDOS ESTRUTURAIS PARA O PERÍODO 2000-2008 EN ESPAÑA

O obxectivo deste estudo é realizar unha análise ex-post e cuantificar o impactoeconómico das intervencións do Obxectivo 1 dos Fondos Estruturais para o período 2000– 2008 en España. A análise céntrase no impacto económico e na análise financeira do: 7.Programa de Desenvolvemento Agrario. Este artigo usa o modelo de análise custobeneficio(ACB) para estudar estas intervencións para ese período en España. O beneficioeconómico neto do programa amosa que todos os programas son viables a nivel de Españae a nivel rexional. Este estudo proba a utilidade da ACB.

A case-control study of psychosocial factors and their relationship to impairment and functionality in multiple sclerosis

The stress effect on multiple sclerosis remains unclear. Moderating psychosocial factors may be involved. This study compares some of them in people with multiple sclerosis and healthy controls, and their association with disease parameters. Coping style, social support, anxiety, alexithymia and early-life stress were measured, along with impairment and functionality. People with multiple sclerosis scored significantly higher on anxiety, alexithymia, and avoidance and instinctive coping but lower in social support. No differences were found in early-life stress. Impairment was related to avoidance, and functionality to avoidance and anxiety. Psychotherapeutic approaches focused on these psychosocial factors may improve functionality, impairment and quality of life in people with multiple sclerosis

Review of temperature sensors as monitors for RF mmW built-in testing and self-calibration schemes

International audienceThis paper presents an overview of the work done so far related to the use of temperature sensors as performance monitors for RF and MMW circuits with the goal to implement built-in testing or self-calibration techniques. The strategy is to embed small temperature sensors on the same silicon die as the circuit under test, taking advantage of empty spaces in the layout. This paper reviews the physical principles, and presents examples that reveal how temperature sensors can be used as functional built-in testers serving to reduce testing costs and enhance yield as part of self-healing strategies