Are covered bonds a substitute for mortgage-backed securities?

Covered bonds and mortgage-backed securities both allow mortgages to be financed with duration-matched bonds. Given the problems in the MBS market during the financial crisis, some suggest that covered bonds might be a substitute for MBS. We examine the use of covered bonds and MBS in the U.S. and Europe, finding that the two are used for different purposes. Covered bonds are used more to increase liquidity than are MBS. MBS are more often used in ways consistent with exploiting some kinds of agency problems.Bonds ; Mortgage-backed securities

Ampliar y descubrir contenidos en Inteligencia Artificial mediante el uso de agregadores de enlaces, votaciones y karma

El tener que acotar y delimitar la serie de contenidos que abordar en un curso es una dificultad a la que debemos enfrentarnos a la hora de planificar la docencia de una materia. Esto es especialmente problemático en materias ya de por sí extensas como las relacionadas con la Inteligencia Artificial y supone tener que omitir partes importantes, tanto teóricas como aplicadas, de un campo en constante evolución. En este trabajo presentamos un intento de mitigar estos problemas haciendo uso de agregadores sociales de enlaces, como digg, reddit o meneane, que permiten que los alumnos exploren por sí mismos, descubran y compartan sus impresiones respecto a aspectos de la materia Inteligencia Artificial que en las clases presenciales no se pueden tratar en profundidad. En nuestro caso hemos implantado nuestro propio agregador de enlaces proponiendo una actividad complementaria cuya evaluación ha sacado provecho de los mecanismos de reputación, o karma, en los que este tipo de herramientas sociales basan su funcionamiento.Peer Reviewe

Utilización de los huesos de la cabeza, cintura pectoral y otolitos para estimar la talla y el peso de la anchoíta (Engraulis anchoita), especie clave en el ecosistema marino patagónico

The Argentine anchovy, Engraulis anchoita, plays a vital role as a key prey species for several marine predators in the north Patagonian marine ecosystem of the Atlantic Ocean. Reconstructing the length and weight of each consumed specimen is essential to provide a detailed description of the trophic ecology of top marine predators. Predictive linear regression equations were calculated for the Patagonian stock of Argentine anchovy to estimate parameters of length-weight relationships using measurements of whole individuals and diagnostic elements such as otoliths, head bones and pectoral fin bones. Among the diagnostic elements analyzed, the cleithrum and dentary exhibited the best fit. This study validates the use of head and pectoral girdle bones as reliable indicators for predicting the weight and length of Argentine anchovy across a wide size range, which corresponds to the target range of various predators. These relationships can contribute to the determination of body condition, estimation of consumed biomass, and calculation of energy density, providing valuable insights into the trophic ecology of predators in the southern Atlantic Ocean.La anchoíta, Engraulis anchoita, juega un papel vital como especie presa clave para varios depredadores marinos en el ecosistema marino patagónico norte del Océano Atlántico. Reconstruir la longitud y el peso de cada espécimen consumido es esencial para proporcionar una descripción detallada de la ecología trófica de los principales depredadores marinos. Se calcularon las ecuaciones de regresión lineal predictiva para el stock patagónico de anchoíta, a fin de estimar los parámetros de las relaciones talla-peso utilizando medidas de individuos completos y elementos de diagnóstico como otolitos, huesos de la cabeza y huesos de la aleta pectoral. Entre los elementos diagnósticos analizados, el cleitro y el dentario exhibieron el mejor ajuste. Este estudio valida el uso de los huesos de la cabeza y la cintura pectoral como indicadores confiables para predecir el peso y la talla de la anchoíta en un amplio rango de tamaños, que corresponden al rango objetivo de varios depredadores. Estas relaciones pueden contribuir a la determinación de la condición corporal, la estimación de la biomasa consumida y el cálculo de la densidad de energía, proporcionando información valiosa sobre la ecología trófica de los depredadores en el Océano Atlántico sur

New lanthanide phosphonates structures obtained using XRPD data

5 páginas, 2 figuras, 3 tablas.-- Trabajo presentado como póster a la 12th European Powder Diffraction Conference (EPDIC 2010).-- et al.Seven lanthanide diphosphonates, [H3N(CH2)4NH3]Ln[hedpH][hedpH2] (Ln = La, Pr, Sm, Eu, Gd, Tb, Er; hedp = 1 hydroxyethylidenediphosphonate) have been synthesized with 1,4-diaminobutane as the template. The structures were obtained starting from the known X-ray single crystal model of lanthanum compound, with the X-ray powder diffraction data for these seven compounds. H-atoms were introduced using geometrical considerations. Rietveld fits of the experimental diffractograms confirm the isostructurality of all compounds in the series, and show the different behaviour between the two distances M-M existing in the structures.Financial support from Spanish MICINN (MAT2006-01997, MAT2010-15095 and ‘Factoría de Cristalización’ Consolider Ingenio 2010), Un-iversidad de Oviedo and Banco Santander is acknowledged. FEDER support is also acknowledged.Peer reviewe

Quantifying the contamination by old main-sequence stars in young moving groups: the case of the Local Association

The associations and moving groups of young stars are excellent laboratories for investigating stellar formation in the solar neighborhood. Previous results have confirmed that a non-negligible fraction of old main-sequence stars is present in the lists of possible members of young stellar kinematic groups. A detailed study of the properties of these samples is needed to separate the young stars from old main-sequence stars with similar space motion, and identify the origin of these structures. We used stars possible members of the young (~ 10 - 650 Myr) moving groups from the literature. To determine the age of the stars, we used several suitable age indicators for young main sequence stars, i.e., X-ray fluxes and other photometric data. We also used spectroscopic data, in particular the equivalent width of the lithium line Li I and Halpha, to constrain the range of ages of the stars. By combining photometric and spectroscopic data, we were able to separate the young stars (10 - 650 Myr) from the old (> 1 Gyr) field ones. We found, in particular, that the Local Association is contaminated by old field stars at the level of ~30%. This value must be considered as the contamination for our particular sample, and not of the entire Local Association. For other young moving groups, it is more difficult to estimate the fraction of old stars among possible members. However, the level of X-ray emission can, at least, help to separate two age populations: stars with <200 Myr and stars older than this. Our results are consistent with a scenario in which the moving groups contain both groups of young stars formed in a recent star-formation episode and old field stars with similar space motion. Only by combining X-ray and optical spectroscopic data is it possible to distinguish between these two age populations.Comment: 7 pages, 7 figures. Accepted for publication in A&

Techno-economic feasibility of ionic liquids-based CO2 chemical capture processes

A techno-economic assessment of Ionic Liquids (ILs)-based post-combustion, biogas and pre-combustion CO2 chemical capture processes was carried out using Aspen Plus and Aspen Process Economic Analyzer (APEA). This cost estimation procedure is newly integrated to our COSMO-based/Aspen Plus methodology used to design the chemical absorption processes with 90% of CO2 capture. The equipment investment and variable operating cost were analyzed relating to the process operating conditions and the IL performance. The total annualized cost was used as the index to economically evaluate the processes at three CO2 treatment capacities and employing three different ILs: [P2228][CNPyr], [P66614][CNPyr] and [Bmim][acetate]. It benefits from economy of scale as well as it is directly related to both IL enthalpy of reaction and process gap capacity, being [P2228][CNPyr] -which has the most exothermic reaction and highest gap capacity- the solvent achieving the lowest costs. Current results indicate that operating at vacuum pressure to better regenerate the IL entails a remarkable cost penalty. Hence, both capital (CAPEX) and operational expenses (OPEX) could be reduced to achieve a total cost of 81.32 $/tCO2 for [P2228][CNPyr] in post-combustion CO2 capture when regenerating the IL at atmospheric pressure and 121.5 °C. Three IL pricing basis were considered when calculating the solvent cost. A conservative IL scaled up price of 50$/kg only increments around 5% the total annualized cost of the processThe authors are grateful to Ministerio de Economía y Competitividad of Spain (project CTQ2017-89441-R) and Comunidad de Madrid (project P2018/EMT4348) for financial support and Centro de Computación Científica de la Universidad Autónoma de Madrid for computational facilitie

«Emulan el firmamento»: las joyas en la poesía de Quevedo

Within the framework of the importance of money in Quevedo, this paper aims to examine the presence of jewelry in Quevedo’s poetry from an artistic, intertextual and rhetorical perspective. Starting with some general considerations about the treasures in Quevedo’s work, it goes on to study some poems and a detailed commentary on the sonnet “Portrait of Lisi that he brought in a ring”.Dentro del marco de la importancia del dinero en Quevedo, en el presente trabajo se pretende examinar la presencia de las joyas en la poesía quevediana desde una perspectiva artística, intertextual y retórica. A partir de unas consideraciones generales sobre los tesoros en la obra de Quevedo, se pasa al estudio de algunos poemas y al comentario detallado del soneto “Retrato de Lisi que traía en una sortija”

NGC 6067: A young and massive open cluster with high metallicity

© 2017 The Authors. NGC6067 is a young open cluster hosting the largest population of evolved stars among known Milky Way clusters in the 50-150 Ma age range. It thus represents the best laboratory in our Galaxy to constrain the evolutionary tracks of 5-7M⊙ stars. We have used high-resolution spectra of a large sample of bright cluster members (45), combined with archival photometry, to obtain accurate parameters for the cluster as well as stellar atmospheric parameters.We derive a distance of 1.78 ± 0.12 kpc, an age of 90 ± 20 Ma and a tidal radius of 14.8 -3.2+6.8 arcmin. We estimate an initial mass above 5700M⊙, for a present-day evolved population of two Cepheids, two A supergiants and 12 red giants with masses ≈6M⊙. We also determine chemical abundances of Li, O, Na, Mg, Si, Ca, Ti, Ni, Rb, Y and Ba for the red clump stars. We find a supersolar metallicity, [Fe/H]=+0.19 ± 0.05, and a homogeneous chemical composition, consistent with the Galactic metallicity gradient. The presence of a Li-rich red giant, star 276 with A(Li)=2.41, is also detected. An overabundance of Ba is found, supporting the enhanced s-process. The ratio of yellow to red giants is much smaller than 1, in agreement with models with moderate overshooting, but the properties of the cluster Cepheids do not seem consistent with current Padova models for supersolar metallicity