Nitrogen on the table: the influence of food choices on nitrogen emissions and the European environment

This ENA Special Report has been prepared by the Expert Panel on Nitrogen and Food of the UNECE Task Force on Reactive Nitrogen. It examines nitrogen and other pollution losses from the food system and assesses the potential impacts of alternative diets on emissions of nitrogen to air and water. It then considers the potential impacts on land-use change and associated greenhouse gas emissions. The study finds that reductions in reactive nitrogen emissions associated with decreased intake of meat and dairy products would have substantial benefits, not only within the EU, but also at continental and global scales. The scenarios also match to consumption patterns that are better aligned with international dietary recommendations

The Exotic Eclipsing Nucleus of the Ring Planetary Nebula SuWt2

SuWt2 is a planetary nebula (PN) consisting of a bright ionized thin ring seen nearly edge-on. It has a bright (V=12) central star, too cool to ionize the PN, which we discovered to be an eclipsing binary. A spectrum from IUE did not reveal a UV source. We present extensive ground-based photometry and spectroscopy of the central binary collected over the ensuing two decades, resulting in the determination that the orbital period of the eclipsing pair is 4.9 d, and consists of two nearly identical A1 V stars, each of mass ~2.7 M_sun. The physical parameters of the A stars, combined with evolutionary tracks, show that both are in the short-lived "blue-hook" evolutionary phase that occurs between the main sequence and the Hertzsprung gap, and that the age of the system is about 520 Myr. One puzzle is that the stars' rotational velocities are different from each other, and considerably slower than synchronous with the orbital period. It is possible that the center-of-mass velocity of the eclipsing pair is varying with time, suggesting that there is an unseen third orbiting body in the system. We propose a scenario in which the system began as a hierarchical triple, consisting of a ~2.9 M_sun star orbiting the close pair of A stars. Upon reaching the AGB stage, the primary engulfed the pair into a common envelope, leading to a rapid contraction of the orbit and catastrophic ejection of the envelope into the orbital plane. In this picture, the exposed core of the initial primary is now a white dwarf of ~0.7 M_sun, orbiting the eclipsing pair, which has already cooled below the detectability possible by IUE at our derived distance of 2.3 kpc and a reddening of E(B-V)=0.40. The SuWt2 system may be destined to perish as a Type Ia supernova. (Abridged)Comment: 60 pages, 11 figure, to appear in the Astronomical Journa

Optical characterization of WISE selected blazar candidates

Context. Over the last decade more than five thousand γ-ray sources have been detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope. Given the positional uncertainty of the telescope, nearly 30% of these sources remain without an obvious counterpart at lower energies. This has motivated the release of new catalogs of γ-ray counterpart candidates and several follow up campaigns in the last decade. Aims. Recently, two new catalogs of blazar candidates were released. These are the improved and expanded version of the WISE Blazar-Like Radio-Loud Sources (WIBRaLS2) catalog and the Kernel Density Estimation selected candidate BL Lacs (KDEBLLACS) catalog, both selecting blazar-like sources based on their infrared colors from the Wide-field Infrared Survey Explorer (WISE). In this work we characterize these two catalogs, clarifying the true nature of their sources based on their optical spectra from SDSS data release 15, thus testing their efficiency in selecting true blazars. Methods. We first selected all WIBRaLS2 and KDEBLLACS sources with available optical spectra in the footprint of Sloan Digital Sky Survey data release 15. We then analyzed these spectra to verify the nature of each selected candidate and to measure the fraction of the catalogs composed by spectroscopically confirmed blazars. Finally, we evaluated the impact of selection effects, especially those related to optical colors of WIBRaLS2/KDEBLLACS sources and their optical magnitude distributions. Results. We found that at least ∼30% of each catalog is made up of confirmed blazars, with quasars being the major contaminants in the case of WIBRaLS2 (≈58%) and normal galaxies in the case of KDEBLLACS (≈38.2%). The spectral analysis also allowed us to identify the nature of 11 blazar candidates of uncertain type (BCUs) from the Fermi-LAT fourth Point Source Catalog (4FGL) and to find 25 new BL Lac objects.Fil: de Menezes, Raniere. Universidade Do Sao Paulo. Instituto Astronomia, Geofísica E Ciencias Atmosfericas. Departamento de Astronomia; Brasil. Università degli Studi di Torino; ItaliaFil: Peña Herazo, Harold A.. Instituto Nacional de Astrofísica; México. Università di Torino; Italia. Istituto Nazionale Di Fisica Nucleare.; Italia. Osservatorio Astrofisico di Torino; ItaliaFil: Marchesini, Ezequiel Joaquín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Istituto Nazionale Di Fisica Nucleare.; Italia. Università di Torino; ItaliaFil: D´Abrusco, Raffaele. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Masetti, Nicola. Osservatorio di Astrofisica e Scienza dello Spazio; Italia. Universidad Andrés Bello; ChileFil: Nemmen, Rodrigo. Universidade Do Sao Paulo. Instituto Astronomia, Geofísica E Ciencias Atmosfericas. Departamento de Astronomia; BrasilFil: Massaro, Francesco. Università di Torino; Italia. Istituto Nazionale Di Fisica Nucleare.; Italia. Osservatorio Astrofisico di Torino; Italia. Consorzio Interuniversitario per la Fisica Spaziale ; ItaliaFil: Ricci, Federica. Pontificia Universidad Católica de Chile; ChileFil: Landoni, Marco. Osservatorio Astronomico di Brera; ItaliaFil: Paggi, Alessandro. Università di Torino; ItaliaFil: Smith, Howard A.. Harvard-Smithsonian Center for Astrophysics; Estados Unido

Semi-Markov Graph Dynamics

In this paper, we outline a model of graph (or network) dynamics based on two ingredients. The first ingredient is a Markov chain on the space of possible graphs. The second ingredient is a semi-Markov counting process of renewal type. The model consists in subordinating the Markov chain to the semi-Markov counting process. In simple words, this means that the chain transitions occur at random time instants called epochs. The model is quite rich and its possible connections with algebraic geometry are briefly discussed. Moreover, for the sake of simplicity, we focus on the space of undirected graphs with a fixed number of nodes. However, in an example, we present an interbank market model where it is meaningful to use directed graphs or even weighted graphs.Comment: 25 pages, 4 figures, submitted to PLoS-ON

Exploratory Analysis of the Copy Number Alterations in Glioblastoma Multiforme

The Cancer Genome Atlas project (TCGA) has initiated the analysis of multiple samples of a variety of tumor types, starting with glioblastoma multiforme. The analytical methods encompass genomic and transcriptomic information, as well as demographic and clinical data about the sample donors. The data create the opportunity for a systematic screening of the components of the molecular machinery for features that may be associated with tumor formation. The wealth of existing mechanistic information about cancer cell biology provides a natural reference for the exploratory exercise.Glioblastoma multiforme DNA copy number data was generated by The Cancer Genome Atlas project for 167 patients using 227 aCGH experiments, and was analyzed to build a catalog of aberrant regions. Genome screening was performed using an information theory approach in order to quantify aberration as a deviation from a centrality without the bias of untested assumptions about its parametric nature. A novel Cancer Genome Browser software application was developed and is made public to provide a user-friendly graphical interface in which the reported results can be reproduced. The application source code and stand alone executable are available at (http://code.google.com/p/cancergenome) and (http://bioinformaticstation.org), respectively.The most important known copy number alterations for glioblastoma were correctly recovered using entropy as a measure of aberration. Additional alterations were identified in different pathways, such as cell proliferation, cell junctions and neural development. Moreover, novel candidates for oncogenes and tumor suppressors were also detected. A detailed map of aberrant regions is provided

The influence of binarity on dust obscuration events in the planetary nebula M 2-29 and its analogues

The central star of the planetary nebula (CSPN) M 2-29 shows an extraordinary R Coronae Borealis-like fading event in its optical lightcurve. The only other CSPN to show these events are CPD-568032 (Hen 3-1333) and V651 Mon (NGC 2346). Dust cloud formation in the line of sight appears responsible but the exact triggering mechanism is not well understood. Understanding how planetary nebulae (PNe) trigger dust obscuration events may help understand the same process in a wide range of objects including Population-I WC9 stars, symbiotic stars and perhaps Asymptotic Giant Branch (AGB) stars with long secondary periods (LSPs). A binary scenario involving an eccentric, wide companion that triggers dust formation via interaction at periastron is a potential explanation that has been suggested for LSP variables. Model fits to the lightcurves of CPD-568032 and M 2-29 show the dust forms in excess of 70 AU at the inner edge of a dust disk. In the case of CPD-568032 this radius is far too large to coincide with a binary companion trigger, although a binary may have been responsible for the formation of the dust disk. We find no direct evidence to support previous claims of binarity in M 2-29 either from the OGLE lightcurve or deep medium-resolution VLT FLAMES spectroscopy of the CSPN. We classify the CSPN as Of(H) with T_eff=50+-10 kK and log g=4.0+-0.3. We find a mean distance of 7.4+-1.8 kpc to M 2-29 at which the M_V=-0.9 mag CSPN could potentially hide a subgiant luminosity or fainter companion. A companion would help explain the multiple similarities with D'-type symbiotic stars whose outer nebulae are thought to be bona-fide PNe. The 7.4 kpc distance, oxygen abundance of 8.3 dex and Galactic coordinates (l=4.0, b=-3.0) prove that M 2-29 is a Galactic Bulge PN and not a Halo PN as commonly misconceived.Comment: 15 pages, 14 figures, 7 tables. Accepted for publication in A\&

Sparticle Mass Spectra from SO(10) Grand Unified Models with Yukawa Coupling Unification

We examine the spectrum of superparticles obtained from the minimal SO(10) grand unified model, where it is assumed the gauge symmetry breaking yields the Minimal Supersymmetric Standard Model (MSSM) as the effective theory at $M_{GUT}\sim 2\times 10^{16}$ GeV. In this model, unification of Yukawa couplings implies a value of $\tan\beta\sim 45-55$. At such high values of $\tan\beta$, assuming universality of scalar masses, the usual mechanism of radiative electroweak symmetry breaking breaks down. We show that a set of weak scale sparticle masses consistent with radiative electroweak symmetry breaking can be generated by imposing non-universal GUT scale scalar masses consistent with universality within SO(10) plus extra $D$-term contributions associated with the reduction in rank of the gauge symmetry group when SO(10) spontaneously breaks to $SU(3)\times SU(2)\times U(1)$. We comment upon the consequences of the sparticle mass spectrum for collider searches for supersymmetry. One implication of SO(10) unification is that the light bottom squark can be by far the lightest of the squarks. This motivates a dedicated search for bottom squark pair production at $p\bar{p}$ and $e^+e^-$ colliders.Comment: 12 page REVTEX file including 3 PS figures; revised manuscript includes minor changes to coincide with published versio

A self‐assembled anion‐binding cryptand for the highly selective liquid‐liquid extraction of phosphate anions

The ligands L1 and L2 form trinuclear self‐assembled complexes with Cu2+ (i.e. [(L1)2Cu3]6+ or [(L2)2Cu3]6+) both of which act as a host to a variety of anions. Inclusion of long aliphatic chains on these ligands allows the assemblies to extract anions from aqueous media into organic solvents. Phosphate can be removed from water efficiently and highly selectively, even in the presence of other anions

A multiscale hybrid model for pro-angiogenic calcium signals in a vascular endothelial cell

Cytosolic calcium machinery is one of the principal signaling mechanisms by which endothelial cells (ECs) respond to external stimuli during several biological processes, including vascular progression in both physiological and pathological conditions. Low concentrations of angiogenic factors (such as VEGF) activate in fact complex pathways involving, among others, second messengers arachidonic acid (AA) and nitric oxide (NO), which in turn control the activity of plasma membrane calcium channels. The subsequent increase in the intracellular level of the ion regulates fundamental biophysical properties of ECs (such as elasticity, intrinsic motility, and chemical strength), enhancing their migratory capacity. Previously, a number of continuous models have represented cytosolic calcium dynamics, while EC migration in angiogenesis has been separately approached with discrete, lattice-based techniques. These two components are here integrated and interfaced to provide a multiscale and hybrid Cellular Potts Model (CPM), where the phenomenology of a motile EC is realistically mediated by its calcium-dependent subcellular events. The model, based on a realistic 3-D cell morphology with a nuclear and a cytosolic region, is set with known biochemical and electrophysiological data. In particular, the resulting simulations are able to reproduce and describe the polarization process, typical of stimulated vascular cells, in various experimental conditions.Moreover, by analyzing the mutual interactions between multilevel biochemical and biomechanical aspects, our study investigates ways to inhibit cell migration: such strategies have in fact the potential to result in pharmacological interventions useful to disrupt malignant vascular progressio