Structural dichroism in the antiferromagnetic insulating phase of V_2O_3

We performed near-edge x-ray absorption spectroscopy (XANES) at V K edge in the antiferromagnetic insulating (AFI) phase of a 2.8% Cr-doped V_2O_3 single crystal. Linear dichroism of several percent is measured in the hexagonal plane and found to be in good agreement with ab-initio calculations based on multiple scattering theory. This experiment definitively proves the structural origin of the signal and therefore solves a controversy raised by previous interpretations of the same dichroism as non-reciprocal. It also calls for a further investigation of the role of the magnetoelectric annealing procedure in cooling to the AFI phase.Comment: 4 pages 3 figures. To be published in Phys. Rev. B (2005

Territorial government reforms at the time of financial crisis: the dawn of metropolitan cities in Italy

On 1 January 2015 a new institution, the metropolitan city, took its place among the Italian territorial authorities. Despite its incorporation in the Italian Constitution since 2001, the metropolitan city become a reality only when the national government carried out a process of reform and transformation of Italian territorial government by transforming 10 large cities into metropolitan cities and depriving other intermediate governments (regions and provinces) of their fundamental competences. This article critically reviews the activation of metropolitan cities and the reshuffle of Italian territorial authorities. It stresses the way in which this reform marks the shift towards a new phase of Italian regionalism, which is dominated both by a dynamic of recentralizing intergovernmental relations and by the resulting loss for provincial and regional governments

Anatomical and Functional Restoration of the Compromised Occlusion: From Theory to Materials

Many conditions can alter the occlusal interface, from tooth wear to tooth loss. The masticatory system is constituted by many components that can influence each other like muscles, joints, teeth and nervous system. This implies that (a) every change at occlusal level makes the other components to adapt and (b) an occlusal alteration may be the effect of an alteration occurred on muscles or joints. Keeping this in mind, traditional principles of occlusal rehabilitation are analysed, and the choice of the restorative materials is discussed

Ceramic Materials as an Alternative to Titanium for Dental Implant Fabrication

Titanium is the gold standard material to produce dental implants from more than 30 years, showing high success rate in different clinical scenarios. Zirconia implants were recently introduced to overwhelm some aesthetic and biological problems that can arise from titanium. Preclinical studies show that, from a mechanical point of view, zirconia may be a suitable substitute for titanium in implant fabrication. Three-dimensional finite element analysis (FEA) models found no difference between titanium and titanium-zirconium alloy implants, neither for early nor conventional functional loading. Nevertheless, zirconia presents the same osseoconductive properties of the titanium, even if the few clinical studies show survival and success rates slightly inferior for zirconia implants comparing to titanium ones, and long-term follow-ups are missing. For these reasons, the majority of authors agree to be cautious for proposing zirconia implants as widespread substitute of titanium implants

The New Elderly Patient: A Necessary Upgrade

The elderly individual is becoming the most common patient in clinical practice due to the increasing average life span, especially in developed countries. The current elderly patients are different from those of some decades ago. They usually have an active social life, want to be informed, and are actively involved in the current society with consequent high expectations for medical and dental treatment. However, not all the elderly patients are like this. Some of them show limited financial resources, reduced mental and manual skills, and poor motivation. The purpose of this communication is to make a brief characterization of the new elderly population in view of prosthetic and dental management