Uses and attitudes of young people toward technology and mobile telephony

This paper aims at showing how young people are developing new and innovative ways of interacting using technology. Previous literature shows that technology adoption depends not only on the technology per se, but also on situational and contextual issues. Mobile telephony has been claimed to change young people's lifestyles, although only scarce empirical evidence exists. We have conducted an empirical study in which we first analyze the existence of differences in technology adoption, acquisition, and usage of technology and mobile telephony between young people in general and those that are online. We find that there are some significant differences in certain dimensions. Next, we carried out the same analysis differentiating between young people that assess themselves as technology-savvy and those that consider themselves inexpert in technology matters. We find that patterns of mobile phone usage in these two groups vary significantly along all analyzed dimensions.mobile telephony; Internet; technology adoption; uses and attitudes;

Approximate particle number projection with density dependent forces: Superdeformed bands in the A=150 and A=190 regions

We derive the equations for approximate particle number projection based on mean field wave functions with finite range density dependent forces. As an application ground bands of even-A superdeformed nuclei in the A=150 and A=190 regions are calculated with the Gogny force. We discuss nuclear properties such as quadrupole moments, moments of inertia and quasiparticle spectra, among others, as a function of the angular momentum. We obtain a good overall description.Comment: 31 pages, 10 figures, 3 appendices. In press in Nucl. Phy

Mean-field Based Approaches to Pairing Correlations in Atomic Nuclei

The evolution of the pairing correlations from closed shell to middle shell nuclei is analyzed with a Finite Range Density Dependent interaction in the Sn isotopes. As theoretical approaches we use the Hartree-Fock-Bogoliubov, the Lipkin-Nogami, their particle number projected counterparts and the full variation after particle number projection method. We find that whereas all approaches succeed rather well in the description of the total energy they differ significantly in the pairing correlation content of the wave functions. The description of the evolution from the weak to the strong pairing regime is also approach dependent, specially at shell closure.Comment: 14 pages, 5 figure

A variational approach to approximate particle number projection with effective forces

Kamlah's second order method for approximate particle number projection is applied for the first time to variational calculations with effective forces. High spin states of normal and superdeformed nuclei have been calculated with the finite range density dependent Gogny force for several nuclei. Advantages and drawbacks of the Kamlah second order method as compared to the Lipkin-Nogami recipe are thoroughly discussed. We find that the Lipkin-Nogami prescription occasionally may fail to find the right energy minimum in the strong pairing regime and that Kamlah's second order approach, though providing better results than the LN one, may break down in some limiting situations.Comment: 16 pages, 8 figure

Charge- and parity-projected Hartree-Fock method for the strong tensor correlation and its application to the alpha particle

We propose a new mean-field-type framework which can treat the strong correlation induced by the tensor force. To treat the tensor correlation we break the charge and parity symmetries of a single-particle state and restore these symmetries of the total system by the projection method. We perform the charge and parity projections before variation and obtain a Hartree-Fock-like equation, which is solved self-consistently. We apply the Hartree-Fock-like equation to the alpha particle and find that by breaking the parity and charge symmetries, the correlation induced by the tensor force is obtained in the projected mean-field framework. We emphasize that the projection before the variation is important to pick up the tensor correlation in the present framework.Comment: 21 pages, 2 figure

Structure-activity relationships on cynnamoyl derivatives as inhibitors of p300 Histone acetyltransferase

Human p300 is a polyhedric transcriptional coactivator, playing a crucial role by acetylating histones on specific lysine residues. A great deal of evidences shows that p300 is involved in several diseases as leukemia, tumors and viral infection. Its involvement in pleiotropic biological roles and connections to diseases provide the rationale as to how its modulation could represent an amenable drug target. Several p300 inhibitors (HATi) have been described so far, but all suffer from low potency, lack of specificity or low cell-permeability, highlighting the need to find more effective inhibitors. Our cinnamoyl derivative, RC 56, was identified as active and selective p300 inhibitor, proving to be a good hit candidate to investigate the structure-activity relationship towards p300. Herein we describe the design, synthesis and biological evaluation of new HATi structurally related to our hit, investigating, moreover, the interactions between p300 and the best-emerged hits by means of induced fit docking and molecular dynamics simulations, gaining insight on the peculiar chemical features that influenced their activity toward the targeted enzyme

Constructive characterization of historical rammed-earth walls in Almohad fortresses in the ancient Reign of Seville

La mayor parte del patrimonio monumental andaluz construido en tierra corresponde a edificaciones militares levantadas en tapial entre los siglos XII al XV. Las del Antiguo Reino de Sevilla constituyen un grupo muy significativo, muchas de las cuales han sido objeto de intervenciones en las últimas décadas. En este trabajo se determinan, analizan y evalúan los principales rasgos técnicos y métricos de las fábricas de tapia de este ámbito espacial de época almohade, con un triple fin: aportar directrices que garanticen una restauración coherente y respetuosa con el bien patrimonial, avanzar en el conocimiento de los usos históricos de esta técnica constructiva y plantear hipótesis en relación a fábricas de adscripción cronológica incierta. Para ello, se implementa la metodología propuesta por los autores en trabajos precedente

Relativistic Nuclear Energy Density Functionals: Mean-Field and Beyond

Relativistic energy density functionals (EDF) have become a standard tool for nuclear structure calculations, providing a complete and accurate, global description of nuclear ground states and collective excitations. Guided by the medium dependence of the microscopic nucleon self-energies in nuclear matter, semi-empirical functionals have been adjusted to the nuclear matter equation of state and to bulk properties of finite nuclei, and applied to studies of arbitrarily heavy nuclei, exotic nuclei far from stability, and even systems at the nucleon drip-lines. REDF-based structure models have also been developed that go beyond the static mean-field approximation, and include collective correlations related to the restoration of broken symmetries and to fluctuations of collective variables. These models are employed in analyses of structure phenomena related to shell evolution, including detailed predictions of excitation spectra and electromagnetic transition rates.Comment: To be published in Progress in Particle and Nuclear Physic

Nuclear structure far from stability

Modern nuclear structure theory is rapidly evolving towards regions of exotic short-lived nuclei far from stability, nuclear astrophysics applications, and bridging the gap between low-energy QCD and the phenomenology of finite nuclei. The principal objective is to build a consistent microscopic theoretical framework that will provide a unified description of bulk properties, nuclear excitations and reactions. Stringent constraints on the microscopic approach to nuclear dynamics, effective nuclear interactions, and nuclear energy density functionals, are obtained from studies of the structure and stability of exotic nuclei with extreme isospin values, as well as extended asymmetric nucleonic matter. Recent theoretical advances in the description of structure phenomena in exotic nuclei far from stability are reviewed.Comment: 18 pp, plenary talk, International Nuclear Physics Conference (INPC 2004), Goeteborg, Sweden, June 27 - July 2, 200