Health Promotion During the Life Course. Lifestyle Determinants of Self-Declared Health Status in Some European Countries

Health promotion and health inequalities are both part of one system. Adopting a life course perspective on interventions might help to minimise current health inequalities and boost equity by leveraging on the social determinants of health. Using retrospective data of SHARE, this study is aimed at analysing whether and how some health promotion behaviours (in terms of lifestyle) change the self-perception of health in late adulthood. Approaching health through the life course perspective can be useful to pursue innovative and more effective public health promotion policies by acting on its socioeconomic determinants during people’s lives

Nonmonotonic Evolution of the Blocking Temperature in Dispersions of Superparamagnetic Nanoparticles

We use a Monte Carlo approach to simulate the influence of the dipolar interaction on assemblies of monodisperse superparamagnetic ${\gamma}-Fe_{2}O_{3}$ nanoparticles. We have identified a critical concentration c*, that marks the transition between two different regimes in the evolution of the blocking temperature ($T_{B}$) with interparticle interactions. At low concentrations (c < c*) magnetic particles behave as an ideal non-interacting system with a constant $T_{B}$. At concentrations c > c* the dipolar energy enhances the anisotropic energy barrier and $T_{B}$ increases with increasing c, so that a larger temperature is required to reach the superparamagnetic state. The fitting of our results with classical particle models and experiments supports the existence of two differentiated regimes. Our data could help to understand apparently contradictory results from the literature.Comment: 13 pages, 7 figure

Determination of the lowest energy structure of Ag8_8 from first-principles calculations

The ground-state electronic and structural properties, and the electronic excitations of the lowest energy isomers of the Ag$_8$ cluster are calculated using density functional theory (DFT) and time-dependent DFT (TDDFT) in real time and real space scheme, respectively. The optical spectra provided by TDDFT predict that the D$_{2d}$ dodecahedron isomer is the structural minimum of Ag$_8$ cluster. Indeed, it is borne out by the experimental findings.Comment: 4 pages, 2 figures. Accepted in Physical Review A as a brief repor

Interface superconductivity: History, developments and prospects

The concept of interface superconductivity was introduced over 50 years ago. Some of the greatest physicists of that time wondered whether a quasi-two-dimensional (2D) superconductor can actually exist, what are the peculiarities of 2D superconductivity, and how does the reduced dimensionality affect the critical temperature (Tc). The discovery of high-temperature superconductors, which are composed of coupled 2D superconducting layers, further increased the interest in reduced dimensionality structures. In parallel, the advances in experimental techniques made it possible to grow epitaxial 2D structures with atomically flat surfaces and interfaces, enabling some of the experiments that were proposed decades ago to be performed finally. Now we know that interface superconductivity can occur at the junction of two different materials (metals, insulators, semiconductors). This phenomenon is being explored intensely; it is also exploited as a means to increase Tc or to study quantum critical phenomena. This research may or may not produce a superconductor with a higher Tc or a useful superconducting electronic device but it will likely bring in new insights into the physics underlying high-temperature superconductivity

Distribution and abundance of molluscs and decapod crustaceans in trawl samples from the Galician Shelf (NW Spain)

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Unexpected Magnetism of Small Silver Clusters

The ground-state electronic, structural, and magnetic properties of small silver clusters, Ag$_n$ (2$\le$n$\le$22), have been studied using a linear combination of atomic Gaussian-type orbitals within the density functional theory. The results show that the silver atoms, which are diamagnetic in bulk environment, can be magnetic when they are grouped together in clusters. The Ag$_{13}$ cluster with icosahedral symmetry has the highest magnetic moment per atom among the studied silver clusters. The cluster symmetry and the reduced coordination number specific of small clusters reveal as a fundamental factor for the onset of the magnetism.Comment: 4 pages, 4 figure

Sardine (Sardina pilchardus Walb.) stock differential distribution by age class in Divisions Vlllc and IXa

A migration pattern of sardine juveniles and spawners is suggested as an explanation of the similarities observed between the stock differential distributions from catch in numbers (1979-1985) and from acoustic estimation (1983-1986), both by age group, in Divisions Vlllc and IXa

Spin excitations in a single La2_2CuO4_4 layer

The dynamics of S=1/2 quantum spins on a 2D square lattice lie at the heart of the mystery of the cuprates \cite{Hayden2004,Vignolle2007,Li2010,LeTacon2011,Coldea2001,Headings2010,Braicovich2010}. In bulk cuprates such as \LCO{}, the presence of a weak interlayer coupling stabilizes 3D N\'{e}el order up to high temperatures. In a truly 2D system however, thermal spin fluctuations melt long range order at any finite temperature \cite{Mermin1966}. Further, quantum spin fluctuations transfer magnetic spectral weight out of a well-defined magnon excitation into a magnetic continuum, the nature of which remains controversial \cite{Sandvik2001,Ho2001,Christensen2007,Headings2010}. Here, we measure the spin response of \emph{isolated one-unit-cell thick layers} of \LCO{}. We show that coherent magnons persist even in a single layer of \LCO{} despite the loss of magnetic order, with no evidence for resonating valence bond (RVB)-like spin correlations \cite{Anderson1987,Hsu1990,Christensen2007}. Thus these excitations are well described by linear spin wave theory (LSWT). We also observe a high-energy magnetic continuum in the isotropic magnetic response. This high-energy continuum is not well described by 2 magnon LSWT, or indeed any existing theories.Comment: Revised version to appear in Nature Materials; 6 pages,4 figure

Migración, ocupación y matrimonio: una aproximación a las relaciones de género de las parejas mixtas en España

En este artículo se analiza la condición de doble ingreso de las parejas como una manera de observar las relaciones de género en el caso particular de las uniones mixtas en el contexto de la creciente presencia de inmigrantes internacionales en España. Para ello se ha considerado simultáneamente la posición de esos hombres y mujeres inmigrantes en los mercados laboral y matrimonial. Con datos de la Encuesta de Población Activa de España para el segundo trimestre de 2007, se analizan la homogamia conyugal y las situaciones ocupacionales de los cónyuges. Las parejas se clasifican distinguiendo si ambos cónyuges están empleados o sólo uno de ellos lo está. Se aplican métodos de análisis multivariado para determinar la probabilidad de los diferentes tipos de uniones de tener uno o doble ingreso. Se realizan análisis diferenciados según la región de origen de los cónyuges inmigrantes (latinoamericanos, europeos occidentales, europeos orientales y magrebíes). En un contexto de aumento de los matrimonios mixtos y de expansión del modelo de doble ingreso en las parejas, los principales resultados revelan que en las uniones mixtas es más frecuente que los cónyuges sean mayores, y que hay una elevada heterogamia educativa; muestran asimismo que la probabilidad de un doble ingreso depende del origen de los cónyuges. Es decir, que las uniones mixtas son más o menos igualitarias en términos de género (dependiendo del sexo y el origen del cónyuge) que las uniones que los españoles están formando en la actualidad