Ab initio study of the charge order and Zener polaron formation in half-doped manganites

The character of the electronic ground state of La0.5Ca0.5MnO3 has been addressed with quantum chemical calculations on large embedded clusters. We find a charge ordered state for the crystal structure reported by Radaelli et al. [Phys. Rev. B 55, 3015 (1997)] and Zener polaron formation in the crystal structure with equivalent Mn sites proposed by Daoud-Aladine et al. [Phys. Rev. Lett. 89, 097205 (2002)]. Important O to Mn charge transfer effects are observed for the Zener polaron.

Adsorption energy and spin state of first-row transition metals adsorbed on MgO(100)

Slab and cluster model spin-polarized calculations have been carried out to study various properties of isolated first-row transition metal atoms adsorbed on the anionic sites of the regular MgO(100) surface. The calculated adsorption energies follow the trend of the metal cohesive energies, indicating that the changes in the metal-support and metal-metal interactions along the series are dominated by atomic properties. In all cases, except for Ni at the generalized gradient approximation level, the number of unpaired electron is maintained as in the isolated metal atom. The energy required to change the atomic state from high to low spin has been computed using the PW91 and B3LYP density-functional-theory-based methods. PW91 fails to predict the proper ground state of V and Ni, but the results for the isolated and adsorbed atom are consistent within the method. B3LYP properly predicts the ground state of all first-row transition atom the high- to low-spin transition considered is comparable to experiment. In all cases, the interaction with the surface results in a reduced high- to low-spin transition energy.

Challenges and Opportunities of Online Entertainment. Proceedings of the 7th International Conference on Internet, Law & Politics. Universitat Oberta de Catalunya, Barcelona, 9-10 July, 2012.

El VIII Congrés Internacional Internet, Dret i Política (IDP 2012) que s'ha dut a terme a Barcelona els dies 9 i 10 de juliol de 2012 sota el títol genèric de "Reptes i oportunitats de l'entreteniment en línia", ha abordat alguns dels principals reptes als que s'enfronta la societat de la informació des de la perspectiva jurídica i politològica. Concretament, els temes centrals han estat el debat sobre l'entreteniment a la xarxa, així com altres qüestions relacionades amb Internet i els drets de propietat intel·lectual, la privacitat, la seguretat o la llibertat d'expressió.

Treatment of cancer with oral drugs: a position statement by the Spanish Society of Medical Oncology

Cancer treatment involves the participation of multiple medical specialties and, as our knowledge of the disease increases, this fact becomes even more apparent. The degree of multidisciplinarity is determined by several factors, which include the severity and type of disease, the increasing diversity in the available pharmacological and non-pharmacological therapies, and the range of specialists involved in cancer therapy, such as medical oncologists, radiotherapists, gynecologists, gastroenterologists, urologists, surgeons, and pneumologists, among others. Across Europe, the situation of cancer care can be variable due to the diversity of health systems, differences in drug reimbursement, and the degree of establishment of Medical Oncology as a medical specialty in the European Union states.