RadioAstron space VLBI imaging of polarized radio emission in the high-redshift quasar 0642 + 449 at 1.6 GHz

Lobanov, A.P. et. al.Context. Polarization of radio emission in extragalactic jets at a sub-milliarcsecond angular resolution holds important clues for understanding the structure of the magnetic field in the inner regions of the jets and in close vicinity of the supermassive black holes in the centers of active galaxies. Aims. Space VLBI observations provide a unique tool for polarimetric imaging at a sub-milliarcsecond angular resolution and studying the properties of magnetic field in active galactic nuclei on scales of less than 10 gravitational radii. Methods. A space VLBI observation of high-redshift quasar TXS 0642+449 (OH 471), made at a wavelength of 18 cm (frequency of 1.6 GHz) as part of the early science programme (ESP) of the RadioAstron mission, is used here to test the polarimetric performance of the orbiting Space Radio Telescope (SRT) employed by the mission, to establish a methodology for making full Stokes polarimetry with space VLBI at 1.6 GHz, and to study the polarized emission in the target object on sub-milliarcsecond scales. Results. Polarization leakage of the SRT at 18 cm is found to be within 9% in amplitude, demonstrating the feasibility of high fidelity polarization imaging with RadioAstron at this wavelength. A polarimetric image of 0642+449 with a resolution of 0.8 mas (signifying an ∼4 times improvement over ground VLBI observations at the same wavelength) is obtained. The image shows a compact core-jet structure with low ( 2%) polarization and predominantly transverse magnetic field in the nuclear region. The VLBI data also uncover a complex structure of the nuclear region, with two prominent features possibly corresponding to the jet base and a strong recollimation shock. The maximum brightness temperature at the jet base can be as high as 4 × 10 K.Y.Y.K., M.M.L., K.V.S., P.A.V. are supported by the Russian Foundation for Basic Research (RFBR) grant 13-02-12103. K.V.S. is also supported by the RFBR grant 14-02-31789. J.L.G. acknowledges support from the Spanish Ministry of Economy and Competitiveness grant AYA2013-40825-P.Peer Reviewe

The optics of an autostereoscopic multiview display

An autostereoscopic head-tracked back projection display that uses an RGB laser illumination source and a fast light engine is described. Images are horizontally scanned columns controlled by a spatial light modulator that directs two or more images in the directions of the apposite viewers’ eyes

Meta-model Pruning

Large and complex meta-models such as those of Uml and its profiles are growing due to modelling and inter-operability needs of numerous\ud stakeholders. The complexity of such meta-models has led to coining\ud of the term meta-muddle. Individual users often exercise only a small\ud view of a meta-muddle for tasks ranging from model creation to construction\ud of model transformations. What is the effective meta-model that represents\ud this view? We present a flexible meta-model pruning algorithm and\ud tool to extract effective meta-models from a meta-muddle. We use\ud the notion of model typing for meta-models to verify that the algorithm\ud generates a super-type of the large meta-model representing the meta-muddle.\ud This implies that all programs written using the effective meta-model\ud will work for the meta-muddle hence preserving backward compatibility.\ud All instances of the effective meta-model are also instances of the\ud meta-muddle. We illustrate how pruning the original Uml metamodel\ud produces different effective meta-models

Memetic Pareto Evolutionary Artificial Neural Networks for the determination of growth limits of Listeria Monocytogenes

The main objective of this work is to automatically design neural network models with sigmoidal basis units for classification tasks, so that classifiers are obtained in the most balanced way possible in terms of CCR and Sensitivity (given by the lowest percentage of examples correctly predicted to belong to each class). We present a Memetic Pareto Evolutionary NSGA2 (MPENSGA2) approach based on the Pareto-NSGAII evolution (PNSGAII) algorithm. We propose to augmente it with a local search using the improved Rprop—IRprop algorithm for the prediction of growth/no growth of L. monocytogenes as a function of the storage temperature, pH, citric (CA) and ascorbic acid (AA). The results obtained show that the generalization ability can be more efficiently improved within a framework that is multi-objective instead of a within a single-objective one

A Class of Partially Solvable Two-Dimensional Quantum Models with Periodic Potentials

The supersymmetrical approach is used to analyse a class of two-dimensional quantum systems with periodic potentials. In particular, the method of SUSY-separation of variables allowed us to find a part of the energy spectra and the corresponding wave functions (partial solvability) for several models. These models are not amenable to conventional separation of variables, and they can be considered as two-dimensional generalizations of Lame, associated Lame, and trigonometric Razavy potentials. All these models have the symmetry operators of fourth order in momenta, and one of them (the Lame potential) obeys the property of self-isospectrality.Comment: 22 pages; some typos corrected; new reference adde

Measurement of the longitudinal and transverse cross-section in e^+e^- annihilation at sqrt(s)=35-44 GeV

An investigation of the polar angle distribution of charged hadrons is presented using data taken by the JADE experiment at the PETRA e^+e^- collider at centre-of-mass energies of 35 and 44 GeV. From fits to the polar angle distribution the longitudinal, sigma_L, and transverse, sigma_T, cross-section relative to the total hadronic are determined at an average energy scale of 36.6 GeV. The results are sigma_L/sigma_tot = 0.067 +/- 0.013, sigma_T/sigma_tot = 0.933 -/+ 0.013 where total errors are given and the results are exactly anti-correlated. Using the next-to-leading order QCD prediction for the longitudinal cross-section, the value alpha_S(36.6 GeV) = 0.150 +/- 0.025 of the strong coupling constant is obtained in agreement with the world average value of alpha_S evolved to an energy scale of 36.6 GeV.Comment: 12 pages, LaTeX2e, 5 .eps-files included, pennames.sty included, submitted to Phys. Lett.

Estados desestructurados en situaciones de conflictos armados

Sumario: Introducción. 1. Qué se entiende por Estado desestructurado. 2. Somalia: un caso tipo sobre el que asentar la teoría. 3. Respuestas actuales del Derecho Internacional Humanitario: sus deficiencias y propuestas de lege ferenda

Effect of a Sepsis Educational Intervention on Hospital Stay

Objectives: To evaluate adherence to the sepsis bundle before and after an educational strategy and its impact on hospital stay. Design: A prospective, analytic, before-and-after study of children with severe sepsis and septic shock who presented to the emergency department. Setting: Carried out from January to December 2014 in the emergency department of a quaternary care hospital. Patients: Of a total of 19,836 children who presented to the emergency department, 4,383 had an infectious pathology, with 203 of these showing severe sepsis and septic shock (124 pre intervention, and 79 post intervention). Interventions: The healthcare providers caring for the patients in pediatric emergency received an educational intervention and an update on the bundle concepts proposed in 2010 by the Pediatric Advanced Life Support program of the American Heart Association and adapted by this study's investigators. Measurements and Main Results: The main cause of sepsis in both groups was respiratory (59 vs 33; p = 0.72), without differences in the Pediatric Index of Mortality 2 score (7.23 vs 8.1; p = 0.23). The postintervention group showed a reduced hospital stay (11.6 vs 7.9 d; p = 0.01), a shorter time before ordering fluid boluses (247 vs 5 min; p = 0.001), the application of the first dose of antibiotic (343 vs 271 min; p = 0.03), and a decreased need for mechanical ventilation (20.1% vs 7.5%; p = 0.01). Postintervention adherence to the complete bundle was 19.2%, compared with the preintervention group, which was 27.7% (p = 0.17). Conclusions: Adherence to a bundle strategy is low following an educational intervention. However, when patients are managed after instruction in guideline recommendations, hospital stay may be significantly reduced. © 2018 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies