La zonación estructural del hercínico del Pirineo Central en el anticlinorio de la Pallaresa

The Pyrenees are an alpine chain with hercynian basement rocks that outcrop in a large area called the Axial Zone. These rocks have been involved in the alpine deformation events although their main structural features resulted from the Hercynian orogeny. A relevant characteristic of the Hercynian basement is a change in structural style in depth which has been commonly studied and interpreted in the Pallaresa Anticlinorium, in the Central Pyrenees. This anticlinorium is a complex hercynian structural unit whose southern part belongs to the suprastructure whereas the northern part corresponds mostly to a transition zone between the infrastructure and the suprastructure. Rocks of the suprastructure show a steeply dipping slaty cleavage as the dominant structure, which is overprinting folds and thrusts rarely going with pervasive deformation. The transition zone results from a slaty cleavage, very often close to the bedding, overprinted by one or two steep crenulation cleavages. A gradual boundary exists between both structural levels and it can be observed that the deformation developing slaty cleavage in the suprastructure grades to a crenulation foliation in the transition zone. The gradual character of that boundary, as seen in the northern end of the transition zone, suggests that the southern sharp boundary is not original. That boundary is interpreted as a northward dipping inverse fault, possibly with Alpine age. That fault causes a relative uplift of the rocks of the transition zone and gives this sharp boundary with the suprastructural levels. It provokes the asymmetry in the Pallaresa anticlinorium

Efectos regionales de la política monetaria : implicaciones para los países de la zona euro

De acuerdo con la teoría de las áreas monetàrias óptimas,los shocks asimétricos tienen un papel fundamental en la determinación de los beneficios y los costes derivados del establecimiento de una área monetaria. En este sentido, diferentes estudios recientes señalan una importante reducción del grado de asimetría de los shocks en términos reales a lo largo de los últimos años entre los países europeos como consecuencia de la mayor coordinación de las políticas económicas y de la aproximación de las estructuras productivas. De todas maneras, una de las cuestiones clave en el nuevo entorno económico, y que no ha sido demasiado considerada a la literatura reciente, es el posible papel desestabilitzador de la política monetaria común como consecuencia de las diferencias en los mecanismos de transmisión de la política monetaria en los distintos países y regiones de la Zona Euro. En este trabajo se considera la mencionada cuestión desde un punto de vista teórico y se analiza empíricamente la existencia de diferencias regionales en los efectos de la política monetaria llevada a término en España a lo largo de los últimos años con la finalidad d identificar los principales determinantes de esta asimetría en el ámbito europeo

Efectos regionales de la política monetaria : implicaciones para los países de la zona euro

De acuerdo con la teoría de las áreas monetàrias óptimas,los shocks asimétricos tienen un papel fundamental en la determinación de los beneficios y los costes derivados del establecimiento de una área monetaria. En este sentido, diferentes estudios recientes señalan una importante reducción del grado de asimetría de los shocks en términos reales a lo largo de los últimos años entre los países europeos como consecuencia de la mayor coordinación de las políticas económicas y de la aproximación de las estructuras productivas. De todas maneras, una de las cuestiones clave en el nuevo entorno económico, y que no ha sido demasiado considerada a la literatura reciente, es el posible papel desestabilitzador de la política monetaria común como consecuencia de las diferencias en los mecanismos de transmisión de la política monetaria en los distintos países y regiones de la Zona Euro. En este trabajo se considera la mencionada cuestión desde un punto de vista teórico y se analiza empíricamente la existencia de diferencias regionales en los efectos de la política monetaria llevada a término en España a lo largo de los últimos años con la finalidad d identificar los principales determinantes de esta asimetría en el ámbito europeo

Price transmission and market power analysis in the Spanish seafood market chain

[cat] Espanya és un dels principals mercats de productes pesquers d’Europa i del món. El consum de productes pesquers ha estat tradicionalment molt important a Espanya, el 2005 es varen consumir 36,7 kg per persona (MAPA, diversos anys). Malgrat això, el mercat i cóm interactuen els diversos nivells de la cadena de comercialització han gaudit de poca atenció. En aquest estudi, utilitzant dades setmanals, s’analitza per als dotze principals productes pesquers, l’elasticitat en la transmissió de preus al llarg de la cadena de comercialització a Espanya (llotja, mercat central i detallista). Finalment s’investiga la presència d’assimetria en la transmissió de preus entre aquests nivells de mercat. Els resultats obtinguts tenen importants implicacions a l’hora d’analitzar la demanda, poder de mercat i marges al llarg del mercat per als productes pesquers.

Willigness to pay for long-term care coverage: the role of private information and self-insurance

Both public and private insurance for long-term care is undeveloped in some European countries such as in Spain and empirical evidence is still limited. This paper aims at exmining the determinants of the demand for Long Term Care (LTC) coverage in Spain using contingent valuation techniques. Our findings indicate that only one-fifth of the population is willing to pay to assure coverage decisions are significantly affected by private information asymmetry and housing tenure in giving rise to self-insurance reduces the probability of insurance being hypothetically purchased.

Worksharing and access discounts in the postal sector with asymmetrics information

This paper analyses the optimal worksharing discount granted to mailers and entrants in a liberalized sector when there is asymmetric information about the Post Office's cost. When the regulator is unable to ascertain which part of total cost of sorting has to be attributed to each sorting facility, the optimal 'accesss discount' given to the entrants is set in a pro-competitive way, thus facilitating the entry of firms that are less afficient than the Post Office. Howerver, with the same asymmetry of information, the optimal 'worksharing discount' given to the mailers is set to favor the Post Office, even when it is less efficient than the mailers in providing the sorting.

Stability of a nonequilibrium steady-state interface

We study the interfacial modes of a driven diffusive model under suitable nonequilibrium conditions leading to possible instability. The external field parallel to the interface, which sets up a steady-state parallel flux, enhances the growth or decay rates of the interfacial modes. More dramatically, asymmetry in the model can introduce an oscillatory component into the interfacial dispersion relation. In certain circumstances, the applied field behaves as a singular perturbation.

Nuclei beyond the drip line

In the Thomas-Fermi model, calculations are presented for nuclei beyond the nuclear drip line at zero temperature. These nuclei are in equilibrium by the presence of an external gas, as may be envisaged in the astrophysical scenario. We find that there is a limiting asymmetry beyond which these nuclei can no longer be made stable.

Isospin-rich nuclei in neutron star matter

Stability of nuclei beyond the drip lines in the presence of an enveloping gas of nucleons and electrons, as prevailing in the inner crust of a neutron star, is studied in the temperature-dependent Thomas-Fermi framework. A limiting asymmetry in the isospin space beyond which nuclei cannot exist emerges from the calculations. The ambient conditions such as temperature, baryon density, and neutrino concentration under which these exotic nuclear systems can be formed are studied in some detail.

Interfacial growth in driven diffusive systems

We have studied the growth of interfaces in driven diffusive systems well below the critical temperature by means of Monte Carlo simulations. We consider the region beyond the linear regime and of large values of the external field which has not been explored before. The simulations support the existence of interfacial traveling waves when asymmetry is introduced in the model, a result previously predicted by a linear-stability analysis. Furthermore, the generalization of the Gibbs-Thomson relation is discussed. The results provide evidence that the external field is a stabilizing effect which can be considered as effectively increasing the surface tension.

Zenith angle distributions at Super-Kamiokande and SNO and the solution of the solar neutrino problem

We have performed a detailed study of the zenith angle dependence of the regeneration factor and distributions of events at SNO and SK for different solutions of the solar neutrino problem. In particular, we discuss the oscillatory behavior and the synchronization effect in the distribution for the LMA solution, the parametric peak for the LOW solution, etc. A physical interpretation of the effects is given. We suggest a new binning of events which emphasizes the distinctive features of the zenith angle distributions for the different solutions. We also find the correlations between the integrated day-night asymmetry and the rates of events in different zenith angle bins. The study of these correlations strengthens the identification power of the analysis.

New CP violation in neutrino oscillations

Measurements of CP-violating observables in neutrino oscillation experiments have been studied in the literature as a way to determine the CP-violating phase in the mixing matrix for leptons. Here we show that such observables also probe new neutrino interactions in the production or detection processes. Genuine CP violation and fake CP violation due to matter effects are sensitive to the imaginary and real parts of new couplings. The dependence of the CP asymmetry on the source-detector distance is different from the standard one and, in particular, enhanced at short distances. We estimate that future neutrino factories will be able to probe in this way new interactions that are up to four orders of magnitude weaker than the weak interactions. We discuss the possible implications for models of new physics.

Anomalous specific-heat jump in a two-component ultracold Fermi gas

The thermodynamic functions of a Fermi gas with spin population imbalance are studied in the temperature-asymmetry plane in the BCS limit. The low-temperature domain is characterized by an anomalous enhancement of the entropy and the specific heat above their values in the unpaired state, decrease of the gap and eventual unpairing phase transition as the temperature is lowered. The unpairing phase transition induces a second jump in the specific heat, which can be measured in calorimetric experiments. While the superfluid is unstable against a supercurrent carrying state, it may sustain a metastable state if cooled adiabatically down from the stable high-temperature domain. In the latter domain the temperature dependence of the gap and related functions is analogous to the predictions of the BCS theory.

Probing elastic anisotropy from defect dynamics in Langmuir monolayers

We study the dynamics of annihilation of point defects in Langmuir monolayers. The absence of hydrodynamic effects allows us to quantitatively relate the asymmetry in defect mobility to the elastic anisotropy of the material, which in turn can be varied through the control of the surface pressure applied to the monolayer. Using the proposed theoretical analysis, we are able to obtain rather elusive equilibrium properties out of relatively simple dynamical measurements. In particular, we measure the elastic constants and their pressure dependence.

Pairing in a two-component ultracold Fermi gas: Phases with broken-space symmetries

We explore the phase diagram of a two-component ultracold atomic Fermi gas interacting with zero-range forces in the limit of weak coupling. We focus on the dependence of the pairing gap and the free energy on the variations in the number densities of the two species while the total density of the system is held fixed. As the density asymmetry is increased, the system exhibits a transition from a homogenous Bardeen-Cooper-Schrieffer (BCS) phase to phases with spontaneously broken global space symmetries. One such realization is the deformed Fermi surface superfluidity (DFS) which exploits the possibility of deforming the Fermi surfaces of the species into ellipsoidal form at zero total momentum of Cooper pairs. The critical asymmetries at which the transition from DFS to the unpaired state occurs are larger than those for the BCS phase. In this precritical region the DFS phase lowers the pairing energy of the asymmetric BCS state. We compare quantitatively the DFS phase to another realization of superconducting phases with broken translational symmetry: the single-plane-wave Larkin-Ovchinnikov-Fulde-Ferrell phase, which is characterized by a nonvanishing center-of-mass momentum of the Cooper pairs. The possibility of the detection of the DFS phase in the time-of-flight experiments is discussed and quantified for the case of 6Li atoms trapped in two different hyperfine states.