Interplay of nematic and magnetic orders in FeSe under pressure

We offer an explanation for the recently observed pressure-induced magnetic state in the iron-chalcogenide FeSe based on \textit{ab initio} estimates for the pressure evolution of the most important Coulomb interaction parameters. We find that an increase of pressure leads to an overall decrease mostly in the nearest-neighbor Coulomb repulsion, which in turn leads to a reduction of the nematic order and the generation of magnetic stripe order. We treat the concomitant effects of band renormalization and the induced interplay of nematic and magnetic order in a self-consistent way and determine the generic topology of the temperature-pressure phase diagram, and find qualitative agreement with the experimentally determined phase diagram.Comment: 13 pages, 6 fig

Large-Scale Regular Morphological Patterns in the Radio Jet of NGC 6251

We report on large-scale, regular morphological patterns found in the radio jet of the nearby radio galaxy NGC 6251. Investigating morphological properties of this radio jet from the nucleus to a radial distance of $\sim$ 300 arcsec ($\approx$ 140 kpc) mapped at 1662 MHz and 4885 MHz by Perley, Bridle, & Willis, we find three chains, each of which consists of five radio knots. We also find that eight radio knots in the first two chains consist of three small sub-knots (the triple-knotty substructures). We discuss the observational properties of these regular morphological patterns.Comment: 8 figures, 15 pages, accepted for publication in A

Simulation of structural and electronic properties of amorphous tungsten oxycarbides

Electron beam induced deposition with tungsten hexacarbonyl W(CO)6 as precursors leads to granular deposits with varying compositions of tungsten, carbon and oxygen. Depending on the deposition conditions, the deposits are insulating or metallic. We employ an evolutionary algorithm to predict the crystal structures starting from a series of chemical compositions that were determined experimentally. We show that this method leads to better structures than structural relaxation based on guessed initial structures. We approximate the expected amorphous structures by reasonably large unit cells that can accommodate local structural environments that resemble the true amorphous structure. Our predicted structures show an insulator to metal transition close to the experimental composition at which this transition is actually observed. Our predicted structures also allow comparison to experimental electron diffraction patterns.Comment: 17 Pages, 11 figure

Synthetic Observations of Simulated Radio Galaxies I: Radio and X-ray Analysis

We present an extensive synthetic observational analysis of numerically- simulated radio galaxies designed to explore the effectiveness of conventional observational analyses at recovering physical source properties. These are the first numerical simulations with sufficient physical detail to allow such a study. The present paper focuses on extraction of magnetic field properties from nonthermal intensity information. Synchrotron and inverse-Compton intensities provided meaningful information about distributions and strengths of magnetic fields, although considerable care was called for. Correlations between radio and X-ray surface brightness correctly revealed useful dynamical relationships between particles and fields. Magnetic field strength estimates derived from the ratio of X-ray to radio intensity were mostly within about a factor of two of the RMS field strength along a given line of sight. When emissions along a given line of sight were dominated by regions close to the minimum energy/equipartition condition, the field strengths derived from the standard power-law-spectrum minimum energy calculation were also reasonably close to actual field strengths, except when spectral aging was evident. Otherwise, biases in the minimum- energy magnetic field estimation mirrored actual differences from equipartition. The ratio of the inverse-Compton magnetic field to the minimum-energy magnetic field provided a rough measure of the actual total energy in particles and fields in most instances, within an order of magnitude. This may provide a practical limit to the accuracy with which one may be able to establish the internal energy density or pressure of optically thin synchrotron sources.Comment: 43 pages, 14 figures; accepted for publication in ApJ, v601 n2 February 1, 200

Structure of the X-ray Emission from the Jet of 3C 273

We present images from five observations of the quasar 3C 273 with the Chandra X-ray Observatory. The jet has at least four distinct features which are not resolved in previous observations. The first knot in the jet (A1) is very bright in X-rays. Its X-ray spectrum is well fitted with a power law with alpha = 0.60 +/- 0.05. Combining this measurement with lower frequency data shows that a pure synchrotron model can fit the spectrum of this knot from 1.647 GHz to 5 keV (over nine decades in energy) with alpha = 0.76 +/- 0.02, similar to the X-ray spectral slope. Thus, we place a lower limit on the total power radiated by this knot of 1.5e43 erg/s; substantially more power may be emitted in the hard X-ray and gamma-ray bands. Knot A2 is also detected and is somewhat blended with knot B1. Synchrotron emission may also explain the X-ray emission but a spectral bend is required near the optical band. For knots A1 and B1, the X-ray flux dominates the emitted energy. For the remaining optical knots (C through H), localized X-ray enhancements that might correspond to the optical features are not clearly resolved. The position angle of the jet ridge line follows the optical shape with distinct, aperiodic excursions of +/-1 deg from a median value of -138.0deg. Finally, we find X-ray emission from the ``inner jet'' between 5 and 10" from the core.Comment: 10 pages, 5 figures; accepted for publication in the Astrophysical Journal Letters. For the color image, see fig1.ps or http://space.mit.edu/~hermanm/papers/3c273/fig1.jp

Plan PrEFiNE: Plan estratégico para la enfermedad de Fabry en Nefrología

Background Renal failure is one of the main causes of death in patients with Fabry disease (FD). Due to the low prevalence of FD, delayed diagnosis and misdiagnosis, often the correct diagnosis is made when organ damage is already present. Early recognition of the disease would allow the prevention of severe complications and the premature death of patients with FD. Objective We present here the PrEFiNE project, which includes a wide spectrum of activities with the aim of improve knowledge and diagnosis of FD. The project is sponsored by Shire Iberia (http://shireiberica.com/) Methods From January 2016 to the end of 2017 several activities will be carried out, starting with a survey to evaluate current FD knowledge among nephrologists; in addition some studies to assess prevalence of this disease will be performed. One study will include patients receiving dialysis, another study will cover kidney transplant patients, and a pilot study in chronic kidney disease in stage 3-5 predialysis. Also planned is a pharmacoeconomic study to focus on burden of FD. At the same time medical education activities will be conducted both on line and on site. Plan for dissemination will include medical publications and diffusion to media. PrEFiNE Project will finish with the publication of a compilation book on FD in Nephrology including all planned activities and proposing recommendations based on results and detected unmet needs. PrEfiNE Plan will be coordinated by severa scientific committees, one at national level and 10 other regionals comittees, tha will be responsible to ensure the maximum scientific quality of proposed activities. An advisory board will supervise the project. Discussion PrEfiNE project will evaluate an action plan focused on improving FD knowledge to make necessary recommendations for an early recognition of the disease. In addition will generate a plan to improve previously undetected needs.Justificación: La enfermedad renal es una de las principales causas de muerte entre los pacientes con enfermedad de Fabry (EF). Al tratarse de una enfermedad de baja prevalencia, se realizan con frecuencia diagnósticos erróneos y retrasados, que a menudo se dan cuando ya se ha producido dan˜ o orgánico. El reconocimiento temprano de la enfermedad permitiría evitar las complicaciones graves y la muerte prematura en estos pacientes. Objetivo: Presentamos en este artículo un resumen del plan PrEFiNE, que incluye un abanico amplio de actividades con el objetivo de mejorar el conocimiento y reconocimiento de la EF entre los nefrólogos. Este proyecto está patrocinado por Shire Ibérica (http://shireiberica.com/). Métodos: Desde enero de 2016 y hasta finales del 2017 se iniciarán distintas actividades, comenzando por una evaluación del grado de conocimiento que existe actualmente sobre la EF. Se incluyen 3 estudios de prevalencia de la EF, que abarcan el espectro de los pacientes con enfermedad renal crónica (pacientes en diálisis, pacientes trasplantados renales y un estudio piloto en pacientes con enfermedad renal crónica en estadio 3–5 prediálisis) y un estudio farmacoeconómico, centrado en el impacto de la carga de la enfermedad. Parale- lamente, se realizarán actividades formativas tanto presenciales como on line, y un amplio plan de comunicación mediante publicaciones y difusión a medios. El proyecto culminará con la publicación de un libro blanco de la EF en Nefrología, que recoja el resultado de todas las actividades y que proponga recomendaciones en respuesta a los resultados y a las necesidades detectadas. El plan PrEFiNE estará coordinado por distintos comités científicos, uno nacional y 10 regionales que garantizarán el desarrollo de las acciones con el máximo rigor científico y será supervisado por un comité asesor. Discusión: El plan PrEFiNE nos permitirá evaluar la utilidad de un proyecto dirigido a mejorar el conocimiento de una enfermedad minoritaria como la EF a nivel nacional, y a partir del cual se podrán establecer las recomendaciones necesarias para mejorar su reconocimiento, además de planes enfocados a mejorar las necesidades no cubiertas detectadas durante su desarroll

REFLECTION OF PRESSURE WAVES AT FLOW IN ELASTIC TUBES

The field of climate change communication (CCC) has recently emerged to address the gap between scientific knowledge of climate change and public motivation to respond. Psychologists in this field have offered helpful strategies for improving the effectiveness of CCC, but their empirical research tends to neglect the ethics of CCC. Philosophers have been more attentive to ethical communication, but they tend to focus on its cognitive dimensions and minimize the affective and social dimensions that contribute to effectiveness. As a result, studies that address ethics and effectiveness in tandem are lacking. This chapter fills this gap by recovering insights from Aristotle’s Rhetoric. By situating all communication within an ethical relationship between speaker and auditor, emphasizing the agency and judgement of auditors, and highlighting ways to build trust, Aristotle offers an art of rhetoric that can help climate scientists communicate both ethically and effectively

Enhanced visual statistical learning in adults with autism.

OBJECTIVE: Individuals with autism spectrum disorder (ASD) are often characterized as having social engagement and language deficiencies, but a sparing of visuospatial processing and short-term memory (STM), with some evidence of supranormal levels of performance in these domains. The present study expanded on this evidence by investigating the observational learning of visuospatial concepts from patterns of covariation across multiple exemplars. METHOD: Child and adult participants with ASD, and age-matched control participants, viewed multishape arrays composed from a random combination of pairs of shapes that were each positioned in a fixed spatial arrangement. RESULTS: After this passive exposure phase, a posttest revealed that all participant groups could discriminate pairs of shapes with high covariation from randomly paired shapes with low covariation. Moreover, learning these shape-pairs with high covariation was superior in adults with ASD than in age-matched controls, whereas performance in children with ASD was no different than controls. CONCLUSIONS: These results extend previous observations of visuospatial enhancement in ASD into the domain of learning, and suggest that enhanced visual statistical learning may have arisen from a sustained bias to attend to local details in complex arrays of visual features

Spin Hall conductivity in the Kane-Mele-Hubbard model at finite temperature

The Kane-Mele model is known to show a quantized spin Hall conductivity at zero temperature. Including Hubbard interactions at each site leads to a quantum phase transition to an XY antiferromagnet at sufficiently high interaction strength. Here, we use the two-particle self-consistent approach (TPSC), which we extend to include spin-orbit coupling, to investigate the Kane-Mele-Hubbard model at finite temperature and half-filling. TPSC is a weak to intermediate coupling approach capable of calculating a frequency- and momentum-dependent self-energy from spin and charge fluctuations. We present results for the spin Hall conductivity and correlation lengths for antiferromagnetic spin fluctuations for different values of temperature, spin-orbit coupling and Hubbard interaction. The vertex corrections, which here are analogues of Maki-Thompson contributions, show a strong momentum dependence and give a large contribution in the vicinity of the phase transition at all temperatures. Their inclusion is necessary to observe the quantization of the spin Hall conductivity for the interacting system in the zero temperature limit. At finite temperature, increasing the Hubbard interaction leads to a decrease of the spin Hall conductivity. This decrease can be explained by band-gap renormalization from scattering of electrons on antiferromagnetic spin fluctuations.Comment: 11 pages, 8 figure