Properties of Graphene: A Theoretical Perspective

In this review, we provide an in-depth description of the physics of monolayer and bilayer graphene from a theorist's perspective. We discuss the physical properties of graphene in an external magnetic field, reflecting the chiral nature of the quasiparticles near the Dirac point with a Landau level at zero energy. We address the unique integer quantum Hall effects, the role of electron correlations, and the recent observation of the fractional quantum Hall effect in the monolayer graphene. The quantum Hall effect in bilayer graphene is fundamentally different from that of a monolayer, reflecting the unique band structure of this system. The theory of transport in the absence of an external magnetic field is discussed in detail, along with the role of disorder studied in various theoretical models. We highlight the differences and similarities between monolayer and bilayer graphene, and focus on thermodynamic properties such as the compressibility, the plasmon spectra, the weak localization correction, quantum Hall effect, and optical properties. Confinement of electrons in graphene is nontrivial due to Klein tunneling. We review various theoretical and experimental studies of quantum confined structures made from graphene. The band structure of graphene nanoribbons and the role of the sublattice symmetry, edge geometry and the size of the nanoribbon on the electronic and magnetic properties are very active areas of research, and a detailed review of these topics is presented. Also, the effects of substrate interactions, adsorbed atoms, lattice defects and doping on the band structure of finite-sized graphene systems are discussed. We also include a brief description of graphane -- gapped material obtained from graphene by attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic

Adherence to and appropriateness of anti-osteoporotic treatments in patients aged 50 and over in the Valencia Region (Spain). The ESOSVAL-AD Study

<p>Summary</p> <p>Background</p> <p>A study to evaluate the adherence to and appropriateness of anti-osteoporotic treatments in a cohort of men and women aged 50 and over participating in the ESOSVAL-R study.</p> <p>Methods/Design</p> <p><it>Design</it>: An observational, longitudinal, prospective cohort study; Study subjects: Men and women aged 50 and over living in the Valencia Region (Spain) who initiated treatment between June 15, 2009, and June 15, 2011, in primary healthcare centers with electronic medical records; <it>Data sources</it>: The main data source will be electronic medical records. <it>Measurement of results: </it>Degree of compliance with and persistence of anti-osteoporotic treatments, and the proportion of patients with appropriate anti-osteoporotic treatment in accordance with the most relevant and high impact recommendations with clearly defined treatment algorithms in Spain (the Spanish National Health System guide (2010), the General Practitioners' Society (2007) and the General Directorate for Pharmacy and Medical Products of Madrid (2007)), and with the National Osteoporosis Foundation (NOF, 2010), and the International Osteoporosis Foundation guidelines (IOF, 2008); <it>Analysis</it>: 1.) Descriptive analysis of patients undergoing treatment and the treatments prescribed; 2.) Descriptive analysis of compliance with and persistence of anti-osteoporotic treatments; 3.) Analysis of factors associated with compliance with and persistence of treatments by Cox proportional hazard regression models, 4.) Descriptive analysis of appropriateness of treatment; 5.) Analysis of factors associated with the appropriateness of treatment by multilevel models (4 levels: patient, doctor, Basic Healthcare Zone/Primary Healthcare Center, and Health Area variables).</p> <p>Discussion</p> <p>ESOSVAL-AD will provide information regarding adherence to osteoporosis treatments and the factors associated with a higher or lower adherence (including the appropriateness of the treatment) in the Spanish context. A better understanding of this phenomenon and the interventions needed to address it would contribute to the increased effectiveness of therapeutic measures, a reduction in morbidity and mortality, and a corresponding reduction in healthcare costs.</p

Effect of temperature on geopolymer and Portland cement composites modified with Micro-encapsulated Phase Change materials

To reduce pollution and global warming, the energy consumption needs to be decreased. Incorporation of Phase Change Materials (PCMs) into building materials can help lower the energy needed to cool and warm buildings, while keeping the indoor temperature at a comfortable level. However, incorporation of PCMs into construction materials alter their performance. In this study, the effect of temperature and addition of two different Micro-encapsulated Phase Change Materials (MPCM) to geopolymer concrete (GPC) and Portland cement concrete (PCC) and pastes was investigated. The samples were examined both below (20 \ub0C) and above (40 \ub0C) the melting points of the PCMs. While the MPCM is not damaged by the alkaline solution, a few microcapsules are broken during the mixing process. Isothermal calorimetry shows that MPCM addition slows down the reaction rate of both geopolymer and Portland cement paste. The setting times were faster when the temperature was increased. The mechanical properties are reduced when MPCM is added to GPC and PCC, although the compressive strength is adequate for building applications. Microstructural studies show more uniform and undamaged edges in the shell-concrete matrix transition zone of GPC than PCC. The samples cured at 40 \ub0C exhibits more air voids in both GPC and PCC than at 20 \ub0C

Vita umana, salute, cura

Partendo dal concetto di vita nel mondo greco si ricostruisce il nesso tra salute, vita effettiva, desiderio di salvezza in epoca greca e modern