The redshift and broad band spectral energy distribution of NRAO 150

Context. NRAO 150 is one of the brightest radio and mm AGN sources on the northern sky. It has been revealed as an interesting source where to study extreme relativistic jet phenomena. However, its cosmological distance has not been reported so far, because of its optical faintness produced by strong Galactic extinction. Aims. Aiming at measuring the redshift of NRAO 150, and hence to start making possible quantitative studies from the source. Methods. We have conducted spectroscopic and photometric observations of the source in the near-IR, as well as in the optical. Results. All such observations have been successful in detecting the source. The near-IR spectroscopic observations reveal strong H$\alpha$ and H$\beta$ emission lines from which the cosmological redshift of NRAO 150 ($z=1.517\pm0.002$) has been determined for the first time. We classify the source as a flat-spectrum radio-loud quasar, for which we estimate a large super-massive black-hole mass $\sim5\times 10^{9} \mathrm{M_\odot}$. After extinction correction, the new near-IR and optical data have revealed a high-luminosity continuum-emission excess in the optical (peaking at $\sim2000$\,\AA, rest frame) that we attribute to thermal emission from the accretion disk for which we estimate a high accretion rate, $\sim30$\,% of the Eddington limit. Conclusions. Comparison of these source properties, and its broad-band spectral-energy distribution, with those of Fermi blazars allow us to predict that NRAO 150 is among the most powerful blazars, and hence a high luminosity -although not detected yet- $\gamma$-ray emitter.Comment: 8 pages, 4 figure

Stability analysis for the background equations for inflation with dissipation and in a viscous radiation bath

The effects of bulk viscosity are examined for inflationary dynamics in which dissipation and thermalization are present. A complete stability analysis is done for the background inflaton evolution equations, which includes both inflaton dissipation and radiation bulk viscous effects. Three representative approaches of bulk viscous irreversible thermodynamics are analyzed: the Eckart noncausal theory, the linear and causal theory of Israel-Stewart and a more recent nonlinear and causal bulk viscous theory. It is found that the causal theories allow for larger bulk viscosities before encountering an instability in comparison to the noncausal Eckart theory. It is also shown that the causal theories tend to suppress the radiation production due to bulk viscous pressure, because of the presence of relaxation effects implicit in these theories. Bulk viscosity coefficients derived from quantum field theory are applied to warm inflation model building and an analysis is made of the effects to the duration of inflation. The treatment of bulk pressure would also be relevant to the reheating phase after inflation in cold inflation dynamics and during the radiation dominated regime, although very little work in both areas has been done, the methodology developed in this paper could be extended to apply to these other problems.Comment: 27 pages, 14 figures, Published version JCA

Light scattering from self-affine fractal silver surfaces with nanoscale cutoff: Far-field and near-field calculations

We study the light scattered from randomly rough, one-dimensional self-affine fractal silver surfaces with nanoscale lower cutoff, illuminated by s- or p-polarized Gaussian beams a few microns wide. By means of rigorous numerical calculations based on the Green theorem integral equation formulation, we obtain both the far- and near-field scattered intensities. The influence of diminishing the fractal lower scale cutoff (from below a hundred, down to a few nanometers) is analyzed in the case of both single realizations and ensemble average magnitudes. For s polarization, variations are small in the far field, being only significant in the higher spatial frequency components of evanescent character in the near field. In the case of p polarization, however, the nanoscale cutoff has remarkable effects stemming from the roughness-induced excitation of surface-plasmon polaritons. In the far field, the effect is noticed both in the speckle pattern variation and in the decrease of the total reflected energy upon ensemble averaging, due to increased absorption. In the near field, more efficient excitation of localized optical modes is achieved with smaller cutoff, which in turn leads to huge surface electric field enhancements.Comment: REVTeX 4, 10 page

Near-field electromagnetic wave scattering from random self-affine fractal metal surfaces: Spectral dependence of local field enhancements and their statistics in connection with surface-enhanced Raman scattering

11 págs.; 10 figs.By means of rigorous numerical simulation calculations based on the Green's theorem integral equation formulation, we study the near electromagnetic field in the vicinity of very rough, one-dimensional self-affine fractal surfaces of Ag, Au, and Cu (for both vacuum and water propagating media) illuminated by a p-polarized field. Strongly localized enhanced optical excitations (hot spots) are found, with electric field intensity enhancements of close to 4 orders of magnitude and widths below a tenth of the incoming wavelength. These effects are produced by the roughness-induced surface-plasmon polariton excitation. We study the characteristics of these optical excitations as well as other properties of the surface electromagnetic field, such as its statistics (probability density function, average, and fluctuations), and their dependence on the excitation spectrum (in the visible and near-infrared regions). Our study is relevant to the use of self-affine fractals as surface-enhanced Raman scattering substrates, where large local and average field enhancements are desired. ©2000 American Physical SocietyThis work was supported by the Spanish Dirección General de Ensenñanza Superior e Investigación Científica y Técnica, through Grant No. PB97-1221. We also thank the Mexican-Spanish CONACYT-CSIC program for partial travel support.Peer Reviewe

Genome-scale modeling of Chinese hamster ovary cells by hybrid semi-parametric flux balance analysis

Funding Information: This work was sponsored by GlaxoSmithKline Biologicals SA whereby the NOVA University Lisbon was engaged under an Agreement for R and D Services. All authors were involved in the conception and design of the study. PD’s lab performed the experiments/acquired the data. JR, GO, RO analyzed and interpreted the data. All authors were involved in drafting the manuscript or critically revising it for important intellectual content. All authors had full access to the data and approved the manuscript before it was submitted by the corresponding author. Publisher Copyright: © 2022, The Author(s).Flux balance analysis (FBA) is currently the standard method to compute metabolic fluxes in genome-scale networks. Several FBA extensions employing diverse objective functions and/or constraints have been published. Here we propose a hybrid semi-parametric FBA extension that combines mechanistic-level constraints (parametric) with empirical constraints (non-parametric) in the same linear program. A CHO dataset with 27 measured exchange fluxes obtained from 21 reactor experiments served to evaluate the method. The mechanistic constraints were deduced from a reduced CHO-K1 genome-scale network with 686 metabolites, 788 reactions and 210 degrees of freedom. The non-parametric constraints were obtained by principal component analysis of the flux dataset. The two types of constraints were integrated in the same linear program showing comparable computational cost to standard FBA. The hybrid FBA is shown to significantly improve the specific growth rate prediction under different constraints scenarios. A metabolically efficient cell growth feed targeting minimal byproducts accumulation was designed by hybrid FBA. It is concluded that integrating parametric and nonparametric constraints in the same linear program may be an efficient approach to reduce the solution space and to improve the predictive power of FBA methods when critical mechanistic information is missing.publishersversionpublishe

Collective electromagnetic emission from molecular layers on metal nanostructures mediated by surface plasmons

6 págs.; 3 figs.; PACS number s : 73.20.Mf, 78.30. j, 78.67.Bf, 42.25.FxCollective electromagnetic processes stemming from molecular emission close to complex nanostructured metal surfaces pumped at and/or near surface-plasmon resonances are theoretically investigated. A classical electrodynamics model is used to describe macroscopically the surface molecular layer emission. Generalized Fresnel coefficients are analytically obtained for planar surfaces, indeed predicting collective quenching for redshifted emission at given angles. The model is introduced into a scattering formulation based on surface integral equations in order to explore collective spontaneous emission near metallic nanoantennas and surface-enhanced Raman scattering. Frequency-shifted near-field patterns and properly defined enhancement factors are obtained that manifest collective processes and cannot be simply inferred from calculations of near fields at the pump frequency. © 2007 The American Physical Society.This work was supported in part by the Spanish “Ministerio de Educación y Ciencia” Grant Nos. FIS2006-07894 and FIS2004-0108 and “Comunidad de Madrid” Grant No. S-0505/TIC-0191 and V.G.’s Ph.D. scholarshipPeer Reviewe

Highly fluorinated erbium(III) complexes for emission in the C-band

Two highly fluorinated Er3+ complexes with three 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate (fod) groups and either bipyridine (bipy) or bathophenantholine (bath) as the ancillary ligand emitting at the C-band (third communication window for fiber transmission) are presented. These complexes are the result of a design process aimed at decreasing the vibrational quenching from high frequency oscillators. The structure of [Er(fod)3(bipy)] has been elucidated by single-crystal X-ray diffraction, while Sparkle/PM6 and Sparkle/PM7 semi-empirical calculations have been used to model the ground state geometry for [Er(fod)3(bath)]. Photoluminescence studies confirm sensitization of the Er3+ ions by antenna effect, leading to NIR emission at 1.53 μm. This energy transfer proves to be more efficient for [Er(fod)3(bath)] as a result of the bulkier and more rigid structure of bath diimide. The good thermal stability of the materials up to over 200 °C allows envisaging their use in erbium-doped waveguides, NIR-OLEDs or other optoelectronic devices

Synthesis, structure and physical properties of luminescent Pr(III) ß-diketonate complexes

Near infrared lanthanide(III)-based light conversion molecular devices (LCMDs) are emerging as a promising class of materials for organic light-emitting diodes (OLEDs) in some niche technologies. Three of these molecular materials -two highly coordinated Pr3+ ß-diketonate monomers and a dimer- are presented and their structure and properties are discussed. Particular emphasis is placed on the solid-to-solid transformation observed for the homodinuclear compound