Infrared Observations of AGN

We present results from an imaging and spectroscopic study of the dust properties of Seyfert galaxies in the 1-10um range. The data are compared to state of the art models of torus emission to constrain geometrical and physical properties of the obscuring medium.Comment: 2 pages, to appear in the IAU Symp.No.222 proceedings:"The Interplay among Black Holes, Stars and ISM in Galactic Nuclei", Gramado, Brazil, March 1-5, 200

Compactly Supported Wavelets Derived From Legendre Polynomials: Spherical Harmonic Wavelets

A new family of wavelets is introduced, which is associated with Legendre polynomials. These wavelets, termed spherical harmonic or Legendre wavelets, possess compact support. The method for the wavelet construction is derived from the association of ordinary second order differential equations with multiresolution filters. The low-pass filter associated with Legendre multiresolution analysis is a linear phase finite impulse response filter (FIR).Comment: 6 pages, 6 figures, 1 table In: Computational Methods in Circuits and Systems Applications, WSEAS press, pp.211-215, 2003. ISBN: 960-8052-88-

Storm characterization and simulation for damage evolution models of maritime structures

This paper presents a new approach to statistically characterize and simulate the wave climate under storm conditions. The methodology includes the joint selection of the parameters that identify storm events (significant wave height threshold, minimum storm duration and minimum interarrival time between consecutive storms) by means of hypothesis testing on the distribution functions of the number of storm events and the elapsing time between storms, providing an improved characterization of the parameters that define storm events. The main wave variables and their temporal dependence are characterized by non-stationary mixture distribution functions and a vector autoregressive model. This allows to adequately reproduce the random temporal evolution of storm events, crucial for the study of damage progression in maritime structures without the use of predefined geometries. The long-term time series of storm events and calm periods is obtained using copula functions which analyze the joint dependence of storm duration and interarrival time for separate climate intervals. The model is applied to hindcast data at a location of the Mediterranean sea close to the Granada coast in Spain to show its ability to reproduce wave storm conditions accounting for the time variability of the storminess. An example of application, using a large number of simulations and a damage progression model in a maritime structure, is presented

Black-Hole Mass and Growth Rate at High Redshift

We present new H and K bands spectroscopy of 15 high luminosity active galactic nuclei (AGNs) at redshifts 2.3-3.4 obtained on Gemini South. We combined the data with spectra of additional 29 high-luminosity sources to obtain a sample with 10^{45.2}<\lambda L_{\lambda}(5100A)<10^{47.3} ergs/sec and black hole (BH) mass range, using reverberation mapping relationships based on the H_beta method, of 10^{8.8}-10^{10.7} M_sun. We do not find a correlation of L/L_Edd with M_BH but find a correlation with \lambda L_{\lambda}(5100A) which might be due to selection effects. The L/L_Edd distribution is broad and covers the range ~0.07-1.6, similar to what is observed in lower redshift, lower luminosity AGNs. We suggest that this consistently measured and calibrated sample gives the best representation of L/L_Edd at those redshifts and note potential discrepancies with recent theoretical and observational studies. The lower accretion rates are not in accord with growth scenarios for BHs at such redshifts and the growth times of many of the sources are longer than the age of the universe at the corresponding epochs. This suggests earlier episodes of faster growth at z>~3 for those sources. The use of the C IV method gives considerably different results and a larger scatter; this method seems to be a poor M_BH and L/L_Edd estimator at very high luminosity.Comment: 8 pages (emulateapj), 4 figures. Accepted for publication in Ap

The Morphology of Type Ia Supernovae Light Curves

We present a family of six BVI template light curves for SNe Ia for days -5 and +80, based on high-quality data gathered at CTIO. These templates display a wide range of light curve morphologies, with initial decline rates of their B light curves between m15(B)=0.87 mag and 1.93 mag. We use these templates to study the general morphology of SNe Ia light curves. We find that several of the main features of the BVI templates correlate tightly with m15(B). In particular, the V light curves, which are probably a reasonably good approximation of the bolometric light curves, display an orderly progression in shapes between the most-luminous, slowest-declining events and the least-luminous, fastest-declining SNe. This supports the idea that the observed spectroscopic and photometric sequences of SNe Ia are due primarily to one parameter. Nevertheless, SNe with very similar initial decline rates do show significant differences in their light curve properties when examined in detail, suggesting the influence of one or more secondary parameters.Comment: 32 pages, 15 figures, to appear in the Astronomical Journa

Relationship between the stability and surface tension of the tear film

FCT, QREN and FEDER/COMPETE through CFUM

Caracterización Ecológica en Múltiples Escalas de Sayornis saya y S. phoebe y su Zona de Contacto en las Grandes Planicies

We assessed interspecific ecological relationships between Say's (Sayornis saya) and Eastern (S. phoebe) phoebes at three scales by developing ecological niche models at two spatial extents and comparing the models' predictions with data from local-scale surveys. The two species' habitats differed in several environmental attributes, primarily precipitation, temperature, and vegetation indices, at both extents. Local-scale surveys between -97° and -101° longitude revealed a steep gradation in ratios of occurrences Say's to the Eastern Phoebe, increasing from east to west. Local-scale occurrences coincided with results of ecological niche models at the extent of both the continent and contact zone, except for Eastern Phoebe occurrences and vegetation indices at both extents. Say's Phoebes nested in open country with sparse or no surrounding woodland, whereas Eastern Phoebe nests were primarily along woodland streams but also at seven sites in more open country where Say's Phoebes had nested previously. At the contact-zone extent, the niche space of the Eastern Phoebe was embedded more into that of Say's Phoebe than the converse. Although niche models at the contact-zone extent indicated some potential for contact, competition between these two species for nest sites is probably less important in limiting distributions than are autoecological characteristics

One-pot synthesis of organophosphate monoesters from alcohols

AbstractA one-pot procedure for the phosphorylation of alcohols provides the corresponding phosphate monoesters in improved yields. The protocol features the use of tetrabutylammonium hydrogen phosphate and trichloroacetonitrile, followed by purification of the crude product by flash chromatography on silica gel. The final step, cation exchange chromatography, affords the organophosphates as ammonium salts that are usually required for biochemical applications. The mechanism appears to be phosphate rather than alcohol activation by trichloroacetonitrile

MarineTools.temporal: A Python package to simulate Earth and environmental time series

The assessment of the uncertainty about the evolution of complex processes usually requires different realizations consisting of multivariate temporal signals of environmental data. However, it is common to have only one observational set. MarineTools.temporal is an open-source Python package for the non-stationary parametric statistical analysis of vector random processes suitable for environmental and Earth modelling. It takes a single timeseries of observations and allows the simulation of many time series with the same probabilistic behavior. The software generalizes the use of piecewise and compound distributions with any number of arbitrary continuous distributions. The code contains, among others, multi-model negative log-likely functions, wrappednormal distributions, and generalized Fourier timeseries expansion. Its programming philosophy significantly improves the computing time and makes it compatible with future extensions of scipy.stats. We apply it to the analysis of freshwater river discharge, water currents, and the simulation of ensemble projections of sea waves, to show its capabilities