Glacial geomorphology of the flank of the Hecates Tholus Volcano, Marrs

El volcán Hecates Tholus (32.18°N, 150.28ºE; cuadrante MC-7), de unos 180 km de diámetro y 5.300 metros de altura, es el único edificio de la provincia volcánica de Elysium, en las Tierras Bajas de Marte, en el que se han descrito rasgos geomorfológicos que podrían estar causados por procesos glaciares. Además, distintos autores relacionan la red radial de canales que surcan las laderas del volcán como causadas por la fusión de un antiguo casquete glaciar en la cima del edificio, siendo éste un ejemplo más de las intensas interacciones magma-agua en esta región del planeta, cercana al antiguo océano marciano y que dieron lugar a fenómenos muy interesantes, como los terrenos caóticos de Galaxias Chaos, a pocos kilómetros del volcán. Una característica muy particular de este edificio volcánico es la presencia de dos depresiones anidadas en la base de la ladera Noroeste, de 20 y 60 km de diámetro. La menor de ellas (Depresión A), situada a mayor altitud, ha sido interpretada por algunos autores como causada por una erupción lateral del volcán hace unos 350 Ma. Sin embargo, la de mayor diámetro y situada a menor altitud (Depresión B), no tiene un origen claro, aunque se han discutido distintas hipótesis. En cualquier caso, es especialmente en el interior de estas depresiones donde se han encontrado los rasgos geomorfológicos que podrían estar causados por actividad glacial, como posibles cordones morrénicos y depósitos de till...

Using a CGE Model to Identify the Policy Trade-Off between Unemployment and Inflation: The Efficient Phillips Curve

This paper provides a new reading of a classical economic relation: the short-run Phillips curve. Our point is that, when dealing with inflation and unemployment, policy-making can be understood as a multicriteria decisionmaking problem. Hence, we use so-called multiobjective programming in connection with a computable general equilibrium (CGE) model to determine the combinations of policy instruments that provide efficient combinations of inflation and unemployment. This approach results in an alternative version of the Phillips curve labelled as efficient Phillips curve. Our aim is to present an application of CGE models to a new area of research that can be especially useful when addressing policy exercises with real data. We apply our methodological proposal within a particular regional economy, Andalusia, in the south of Spain. This tool can give some keys for policy advice and policy implementation in the fight against unemployment and inflation.

Breaking the curve with candels: a Bayesian approach to reveal the non-universality of the dust-attenuation law at high redshift

Dust attenuation affects nearly all observational aspects of galaxy evolution, yet very little is known about the form of the dust-attenuation law in the distant universe. Here, we model the spectral energy distributions of galaxies at z ~ 1.5–3 from CANDELS with rest-frame UV to near-IR imaging under different assumptions about the dust law, and compare the amount of inferred attenuated light with the observed infrared (IR) luminosities. Some individual galaxies show strong Bayesian evidence in preference of one dust law over another, and this preference agrees with their observed location on the plane of infrared excess (IRX, L_TIR/L_UV) and UV slope (β). We generalize the shape of the dust law with an empirical model, A_ λ,σ =E(B-V)k_ λ (λ / λ v)^ σ where k_λ is the dust law of Calzetti et al., and show that there exists a correlation between the color excess E(B-V) and tilt δ with δ =(0.62±0.05)log(E(B-V))+(0.26±0.02). Galaxies with high color excess have a shallower, starburst-like law, and those with low color excess have a steeper, SMC-like law. Surprisingly, the galaxies in our sample show no correlation between the shape of the dust law and stellar mass, star formation rate, or β. The change in the dust law with color excess is consistent with a model where attenuation is caused by scattering, a mixed star–dust geometry, and/or trends with stellar population age, metallicity, and dust grain size. This rest-frame UV-to-near-IR method shows potential to constrain the dust law at even higher redshifts (z>3).