Amores y estocadas: vida turbulenta de Don Francisco de Quevedo

Novela histórica recuperada de los archivos del olvido por Ignacio Arellano, aficionado lector, incitado por el reclamo de la vieja colección Capa y Espada ("Amor, aventuras e intriga en el escenario caballeresco y romático de nuestra historia"

Fixed Effect Estimation of Large T Panel Data Models

This article reviews recent advances in fixed effect estimation of panel data models for long panels, where the number of time periods is relatively large. We focus on semiparametric models with unobserved individual and time effects, where the distribution of the outcome variable conditional on covariates and unobserved effects is specified parametrically, while the distribution of the unobserved effects is left unrestricted. Compared to existing reviews on long panels (Arellano and Hahn 2007; a section in Arellano and Bonhomme 2011) we discuss models with both individual and time effects, split-panel Jackknife bias corrections, unbalanced panels, distribution and quantile effects, and other extensions. Understanding and correcting the incidental parameter bias caused by the estimation of many fixed effects is our main focus, and the unifying theme is that the order of this bias is given by the simple formula p/n for all models discussed, with p the number of estimated parameters and n the total sample size.Comment: 40 pages, 1 tabl

On-the-Fly Power-Aware Rendering

Power saving is a prevailing concern in desktop computers and, especially, in battery-powered devices such as mobile phones. This is generating a growing demand for power-aware graphics applications that can extend battery life, while preserving good quality. In this paper, we address this issue by presenting a real-time power-efficient rendering framework, able to dynamically select the rendering configuration with the best quality within a given power budget. Different from the current state of the art, our method does not require precomputation of the whole camera-view space, nor Pareto curves to explore the vast power-error space; as such, it can also handle dynamic scenes. Our algorithm is based on two key components: our novel power prediction model, and our runtime quality error estimation mechanism. These components allow us to search for the optimal rendering configuration at runtime, being transparent to the user. We demonstrate the performance of our framework on two different platforms: a desktop computer, and a mobile device. In both cases, we produce results close to the maximum quality, while achieving significant power savings

First Record of Batrachochytrium dendrobatidis in Pleurodema somuncurense, a Critically Endangered Species from Argentina

The presence of Bd zoosporangia in skin samples of the dead individual coming from the eastern warm branch, which reach temperatures of up to 26°C, suggests the occurrence of a Bd strain adapted to higher temperatures (Bd does not grow well above 25°C: Piotrowsky et al. 2004). Since the two pairs of branches differ by almost 4°C, and knowing that temperature may influences patterns of Bd infection, future field-studies should assess the prevalence of the Bd infection in subpopulations of Valcheta Frog inhabiting at different environmental conditions along the stream.Facultad de Ciencias Naturales y Muse

First Record of Batrachochytrium dendrobatidis in Pleurodema somuncurense, a Critically Endangered Species from Argentina

The presence of Bd zoosporangia in skin samples of the dead individual coming from the eastern warm branch, which reach temperatures of up to 26°C, suggests the occurrence of a Bd strain adapted to higher temperatures (Bd does not grow well above 25°C: Piotrowsky et al. 2004). Since the two pairs of branches differ by almost 4°C, and knowing that temperature may influences patterns of Bd infection, future field-studies should assess the prevalence of the Bd infection in subpopulations of Valcheta Frog inhabiting at different environmental conditions along the stream.Facultad de Ciencias Naturales y Muse

Echelle long-slit optical spectroscopy of evolved stars

We present echelle long-slit optical spectra of a sample of objects evolving off the AGB, most of them in the pre-planetary nebula (pPN) phase, obtained with the ESI and MIKE spectrographs at Keck-II and Magellan-I, respectively. The total wavelength range covered with ESI (MIKE) is ~3900 to 10900 A (~3600 to 7200A). In this paper, we focus our analysis mainly on the Halpha profiles. Prominent Halpha emission is detected in half of the objects, most of which show broad Halpha wings (up to ~4000 km/s). In the majority of the Halpha-emission sources, fast, post-AGB winds are revealed by P-Cygni profiles. In ~37% of the objects Halpha is observed in absorption. In almost all cases, the absorption profile is partially filled with emission, leading to complex, structured profiles that are interpreted as an indication of incipient post-AGB mass-loss. All sources in which Halpha is seen mainly in absorption have F-G type central stars, whereas sources with intense Halpha emission span a larger range of spectral types from O to G. Shocks may be an important excitation agent of the close stellar surroundings for objects with late type central stars. Sources with pure emission or P Cygni Halpha profiles have larger J-K color excess than objects with Halpha mainly in absorption, which suggests the presence of warm dust near the star in the former. The two classes of profile sources also segregate in the IRAS color-color diagram in a way that intense Halpha-emitters have dust grains with a larger range of temperatures. (abridged)Comment: 68 pages, 14 figures, accepted for publication in ApJS (abstract abridged

Variable stars in the bulge globular cluster NGC 6401

We present a study of variable stars in globular cluster NGC 6401. The cluster is only 5.3º away from the Galactic centre and suffers from strong differential reddening. The photometric precision afforded us by difference image analysis resulted in improved sensitivity to variability in formerly inaccessible interior regions of the cluster. We find 23 RRab and 11 RRc stars within one cluster radius (2.4'), for which we provide coordinates, finder-charts and time-series photometry. Through Fourier decomposition of the RR Lyrae star light curves we derive a mean metallicity of [Fe/H]UVES = -1.13 ± 0.06 ([Fe/H]ZW = -1.25 ± 0.06), and a distance of d ≈ 6.35 ± 0.81 kpc. Using the RR Lyrae population, we also determine that NGC 6401 is an Oosterhoff type I cluster.PostprintPeer reviewe