Automatic Curve Fitting Based on Radial Basis Functions and a Hierarchical Genetic Algorithm

Curve fitting is a very challenging problem that arises in a wide variety of scientific and engineering applications. Given a set of data points, possibly noisy, the goal is to build a compact representation of the curve that corresponds to the best estimate of the unknown underlying relationship between two variables. Despite the large number of methods available to tackle this problem, it remains challenging and elusive. In this paper, a new method to tackle such problem using strictly a linear combination of radial basis functions (RBFs) is proposed. To be more specific, we divide the parameter search space into linear and nonlinear parameter subspaces. We use a hierarchical genetic algorithm (HGA) to minimize a model selection criterion, which allows us to automatically and simultaneously determine the nonlinear parameters and then, by the least-squares method through Singular Value Decomposition method, to compute the linear parameters. The method is fully automatic and does not require subjective parameters, for example, smooth factor or centre locations, to perform the solution. In order to validate the efficacy of our approach, we perform an experimental study with several tests on benchmarks smooth functions. A comparative analysis with two successful methods based on RBF networks has been included

MUSE reveals extended circumnuclear outflows in the seyfert 1 NGC 7469

NGC 7469 is a well-known luminous infrared galaxy, with a circumnuclear star formation ring ∼830 pc radius) surrounding a Seyfert 1 active galactic nucleus (AGN). Nuclear unresolved winds were previously detected in X-rays and ultraviolet, as well as an extended biconical outflow in infrared coronal lines. We search for extended outflows by measuring the kinematics of the Hβ and [O III] λ5007 optical emission lines, in data of the Very Large Telescope/Multi-unit Spectroscopic Explorer integral field spectrograph. We find evidence of two outflow kinematic regimes: One slower regime extending across most of the star formation (SF) ring-possibly driven by the massive SF-and a faster regime (with a maximum velocity of -715 km s-1), only observed in [O III], in the western region between the AGN and the massive star-forming regions of the ring, likely AGN-driven. This work shows a case where combined AGN/SF feedback can be effectively spatially resolved, opening up a promising path toward a deeper understanding of feedback processes in the central kiloparsec of AGNSupport from CONACyT (Mexico) grant CB-2016-01-286316 is acknowledged. J.P.T.P. acknowledges DAIP-UGto (Mexico) for granted support (0173/2019). Y.A. acknowledges support from project PID2019-107408GB-C42 (Ministerio de Ciencia e Innovación, Spain). S.F.S. thanks the support of CONACYT grants CB-285080 and FC-2016-01- 1916, and funding from the PAPIIT-DGAPA-IN100519 (UNAM) project. L.G. was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 839090. This work has been partially supported by the Spanish grant PGC2018-095317-B-C21 within the European Funds for Regional Development (FEDER). E.B acknowledges the support from Comunidad de Madrid through the Atracción de Talento grant 2017-T1/TIC-5213. This research has been partially funded by the Spanish State Research Agency (AEI) Project MDM-2017-0737 Unidad de Excelencia “María de Maeztu”- Centro de Astrobiología (INTA-CSIC

Complete Genome Sequence of Houston Virus, a Newly Discovered Mosquito-Specific Virus Isolated from Culex quinquefasciatus in Mexico

ABSTRACT We fully sequenced the genome of Houston virus, a recently discovered mosquito-associated virus belonging to the newly established family Mesoniviridae. The isolate was recovered from Culex quinquefasciatus in southern Mexico, which shows that the geographic range of Houston virus is not restricted to the United States in North America

Hippocampal IGF-1 expression, neurogenesis and slowed aging: clues to longevity from mutant mice

Recent studies point out the important role of IGF and insulin-related signaling pathways in the control of longevity of laboratory animals. The Ames dwarf mouse is a murine model of circulating GH and IGF-1 deficiency that exhibits dwarf phenotype characteristics and significantly extends lifespan. It is interesting to know that Ames dwarf mice do not experience an age-related decline in cognitive function when compared to their young counterparts. In this study, the most recent works on local GH and IGF-1 expression in the hippocampus of Ames mice are briefly reviewed

High voltage calibration method for the CMS RPC detector

The Resistive Plate Chambers (RPC) are used for muon triggers in the CMS experiment. To calibrate the high voltage working-points (WP) and identify degraded detectors due to radiation or chemical damage, a high voltage scan has been performed using 2017 data from pp collisions at a center-of-mass energy of 13 TeV. In this paper, we present the calibration method and the latest results obtained for the 2017 data. A comparison with all scans taken since 2011 is considered to investigate the stability of the detector performance in time

CMSRPC efficiency measurement using the tag-and-probe method

We measure the efficiency of CMS Resistive Plate Chamber (RPC) detectors in proton-proton collisions at the centre-of-mass energy of 13 TeV using the tag-and-probe method. A muon from a Z(0) boson decay is selected as a probe of efficiency measurement, reconstructed using the CMS inner tracker and the rest of CMS muon systems. The overall efficiency of CMS RPC chambers during the 2016-2017 collision runs is measured to be more than 96% for the nominal RPC chambers

RPC radiation background simulations for the high luminosity phase in the CMS experiment

The high luminosity expected from the HL-LHC will be a challenge for the CMS detector. The increased rate of particles coming from the collisions and the radioactivity induced in the detector material could cause significant damage and result in a progressive degradation of its performance. Simulation studies are very useful in these scenarios as they allow one to study the radiation environment and the impact on detector performance. Results are presented for CMS RPC stations considering the operating conditions expected at the HL-LHC