Trade Policy and Factor Prices: An Empirical Strategy

This paper presents a new empirical strategy for estimating the effects of trade policy on domestic factor prices when policy endogeneity is suspected. Absent income effectson factor supplies or domestic prices, the coefficient on the terms of trade can provide an unbiased estimator of the effect of trade barriers on the factor distribution of income for a small economy. In the more general case where income effects are allowed for, we provide a means to quantify and control for the possible bias. We implement our strategy on a cross-national data set of trade policies and income shares of capital and labor. We find little evidence of the existence of Stolper-Samuelson effects, both for the sample as a whole as well as within cones of diversification. Consistent with a model of wage bargaining, we find that the effect of openness on capital shares is greater for countries with higher unionization rates.Factor prices, trade policy, Stolper-Samuelson theorem, wage bargaining

Freed from Illiteracy? A Closer Look at Venezuela’s Robinson Literacy Campaign

We evaluate the success of the Venezuelan government’s latest nationwide literacy program, Misión Robinson, using official Venezuelan government survey data. Controlling for existing trends in literacy rates by age groups over the period 1975 to 2005, we find at most a small positive effect of Robinson on literacy rates, and in many specifications the program impact is statistically indistinguishable from zero. This main result is robust to time series analysis by birth cohort, and to state-level difference-in-differences estimation. The results appear to be inconsistent with recent official claims of the complete eradication of illiteracy in Venezuela, but resonate with existing research on other adult literacy programs, which have usually been expensive failures.

Brighter Branes, enhancement of photon production by strong magnetic fields in the gauge/gravity correspondence

We use the gauge/gravity correspondence to calculate the rate of photon production in a strongly coupled N=4 plasma in the presence of an intense magnetic field. We start by constructing a family of back reacted geometries that include the black D3-brane solution, as a smooth limiting case for B=0, and extends to backgrounds with an arbitrarily large constant magnetic field. This family provides the gravitational dual of a field theory in the presence of a very strong magnetic field which intensity can be fixed as desired and allows us to study its effect on the photon production of a quark-gluon plasma. The inclusion of perturbations in the electromagnetic field on these backgrounds is consistent only if the metric is perturbed as well, so we use methods developed to treat operator mixing to manage these general perturbations. Our results show a clear enhancement of photon production with a significant anisotropy, which, in qualitative agreement with the experiments of heavy ion collisions, is particularly noticeable for low P.Comment: This paper was replaced including metric perturbations for consistency of the calculation, and reports important qualitative changes. 43 page

About Helices and Solvents: VCD and more

Intermolecular forces drive self-organization of molecules, which is ultimately the origin of most the physical and chemical phenomena in Nature. Molecules able to interact themselves by non-covalent forces, as hydrogen bonding and/or hydrophobic attractions, usually form macrostructures in condensed phases (solid, solution). The properties of these aggregates depend of three main factors: the structural and chemical features of the molecules, the nature of intermolecular forces and the environment. The first two drive aggregation in solid state, while in solution the role of the solvent become determinant as it can induce a variety of structural effects on the aggregation behaviour of the solute. In the case of chiral molecules, this property is transferred to the aggregates and supramolecular chirality appears. Here we present our research on chiral molecules that self-organize in solution forming helical structures. We use VCD as the main chiroptical tool, but also supported by other chiroptical spectroscopies (ECD, ROA) and theoretical modelling. In our first steps, we studied the effect of modulating the environmental settings on the helices. Thus, helix handedness was proved highly and reversibly dependent on factors as pH or ionic strength in peptide-mimetic hydrogelators. We also observe how the initial conditions (concentration, temperature) were capable of controlling the helix structure of oligo-p-phenylene-based polymers towards kinetic or thermodynamics pathways. Besides, the structure of the helices can also be the consequence of direct solvent-solute interactions. In this way, we have demonstrated that an achiral solvent can act as a template for chiral organization of N-heterotriangulenes-based organogelators, thus showing the different levels of complexity of the hierarchical organization of supramolecular polymers. But the solvent-helix interactions can be bidirectional. As a nice example, we recorded chiral signals which can be only assigned to the organization of the solvent molecules around helical aggregates of phenylglycine functionalized poly(phenylacetylene)s. The solvent molecules thus form a first solvation shell to which the helix chirality is transferred. The helices would act therefore as a template of the solvent molecules, and the chirality of this external helix would be fully controlled by the solute.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Fuzzy Predictive Controller for Mobile Robot Path Tracking

IFAC Intelligent Components and Instruments for Control Applications, Annecy, France 1997This paper presents a way of implementing a Model Based Predictive Controller (MBPC) for mobile robot path-tracking. The method uses a non-linear model of mobile robot dynamics and thus allows an accurate prediction of the future trajectories. Constraints on the maximum attainable angular velocity is also considered by the algorithm. A fuzzy approach is used to implement the MBPC. The fuzzy controller has been trained using a lookup-table scheme, where the database of fuzzy-rules has been obtained automatically from a set of input-output training patterns, computed with the predictive controller. Experimental results obtained when applying the fuzzy controller to a TRC labmate mobile platform are given in the paper.Ministerio de Ciencia y Tecnología TAP95-0307Ministerio de Ciencia y Tecnología TAP96-884C

El fin del plazo para adaptarse al Grado, las sentencias judiciales sobre su aplicación y análisis desde el punto de vista de la actividad de las Defensorías (Reflexiones en base a sentencias)

De acuerdo con la disposición transitoria segunda del Real Decreto 1393/2007, el 30 de Septiembre de 2017 es la fecha tope para que las universidades españolas puedan realizar exámenes que permitan a los alumnos de las antiguas titulaciones finalizar sus estudios sin la necesidad de tener que adaptarse a la estructura del Grado. Hasta el presente momento, en general, las universidades han permitido la realización de al menos cuatro convocatorias en los dos cursos posteriores a la finalización oficial de la impartición de las enseñanzas de diplomado o licenciado, algo que algunos defensores hemos entendido equivocado pues creíamos que, teniendo como premisa el cumplimiento de las normas de progreso y permanencia, la citada disposición transitoria segunda no obliga a ello. En el presente año 2016 se han hecho públicos los fallos de dos tribunales de lo Contencioso-Administrativo que hacen una interpretación radicalmente opuesta de la norma lo que, a nuestro juicio, lejos de aclarar o facilitar la toma de decisiones respecto a la manera en la que debe aplicarse la citada disposición transitoria, genera una situación cuyo alcance se nos escapa a vislumbrar. En concreto, mientras una de ellas estima que los estudiantes tienen la posibilidad de ser evaluados hasta septiembre de 2017, la otra establece el límite de los dos años posteriores a la de la finalización oficial de cada uno de los estudios. En el presente artículo se pretende hacer unas breves reflexiones sobre los motivos que han conducido a pronunciarnos a favor de los estudiantes que reclaman la posibilidad de realizar exámenes de las asignaturas pendientes hasta septiembre de 2017

Calibrating the Na\"ive Cornell Model with NRQCD

Along the years, the Cornell Model has been extraordinarily successful in describing hadronic phenomenology, in particular in physical situations for which an effective theory of the strong interactions such as NRQCD cannot be applied. As a consequence of its achievements, a relevant question is whether its model parameters can somehow be related to fundamental constants of QCD. We shall give a first answer in this article by comparing the predictions of both approaches. Building on results from a previous study on heavy meson spectroscopy, we calibrate the Cornell model employing NRQCD predictions for the lowest-lying bottomonium states up to N$^3$LO, in which the bottom mass is varied within a wide range. We find that the Cornell model mass parameter can be identified, within perturbative uncertainties, with the MSR mass at the scale $R = 1\,$GeV. This identification holds for any value of $\alpha_s$ or the bottom mass, and for all perturbative orders investigated. Furthermore, we show that: a) the "string tension" parameter is independent of the bottom mass, and b) the Coulomb strength $\kappa$ of the Cornell model can be related to the QCD strong coupling constant $\alpha_s$ at a characteristic non-relativistic scale. We also show how to remove the $u=1/2$ renormalon of the static QCD potential and sum-up large logs related to the renormalon subtraction by switching to the low-scale, short-distance MSR mass, and using R-evolution. Our R-improved expression for the static potential remains independent of the heavy quark mass value and agrees with lattice QCD results for values of the radius as large as $0.8\,$fm, and with the Cornell model potential at long distances. Finally we show that for moderate values of $r$, the R-improved NRQCD and Cornell static potentials are in head-on agreement.Comment: 22 pages, 13 figures, 3 table

Charmonium resonances in the 3.9 GeV/c2c^2 energy region and the X(3915)/X(3930)X(3915)/X(3930) puzzle

An interesting controversy has emerged challenging the widely accepted nature of the $X(3915)$ and the $X(3930)$ resonances, which had initially been assigned to the $\chi_{c0}(2P)$ and $\chi_{c2}(2P)$ $c\bar c$ states, respectively. To unveil their inner structure, the properties of the $J^{PC}\!\!=\!0^{++}$ and $J^{PC}\!\!=\!2^{++}$ charmonium states in the energy region of these resonances are analyzed in the framework of a constituent quark model. Together with the bare $q\bar q$ states, threshold effects due to the opening of nearby meson-meson channels are included in a coupled-channels scheme calculation. We find that the structure of both states is dominantly molecular with a probability of bare $q\bar q$ states lower than $45\%$. Our results favor the hypothesis that $X(3915)$ and $X(3930)$ resonances arise as different decay mechanisms of the same $J^{PC}\!\!=\!2^{++}$ state. Moreover we found an explanation for the recently discovered $M=3860$ MeV$/c^2$ as a $J^{PC}\!\!=\!0^{++}$ $2P$ state and rediscovery the lost $Y(3940)$ as an additional state in the $J^{PC}\!\!=\!0^{++}$ family.Comment: 6 pages, 3 table