Orientation and evidence for recurrent activity
نویسندگان
چکیده
Aims. The goal of this work is a detailed study of the nearby, low power radio galaxy B2 1144+35B. Methods. For this purpose, we performed new Very Long Baseline Array (VLBA) and Very Large Array (VLA) observations. Results. This source has several properties (bright, nearby, large range of spatial structures, visible counterjet, etc.) that make it an excellent astrophysical laboratory for the study of the evolution of radio jets. Here we report the detection of motion in the counterjet at 0.23 ± 0.07 c, which allows us to estimate the orientation of the parsec-scale jet at 33 ± 7 from the line of sight, with an intrinsic velocity of (0.94 −0.11)c. We also report on a brightening of the core at high frequencies which we suggest could be the result of a new component emerging from the core. High dynamic range VLBA observations at 5 GHz reveal, for the first time, extended emission connecting the core with the bright complex of emission that dominates the flux density of the parsec scale structure at frequencies below 20 GHz. The evolution of this bright complex is considered and its slow decline in flux density is interpreted as the result of an interaction with the interstellar medium of the host galaxy.
منابع مشابه
Results of Open Bankart Surgery for Recurrent Anterior Shoulder Dislocation with Glenoid Bone Defect and Concomitant Hill-Sachs Lesion
Background: Open Bankart surgery is the main treatment procedure in patients with recurrent anterior shoulder dislocation, especially in cases with glenoid bone defect. The goal of this study was to determine the outcomes after open Bankart surgery in cases of recurrent anterior shoulder dislocation with glenoid bone defects and concomitant Hill-Sachs lesions. Methods: Between 2006 and 2010,...
متن کاملDependence of Orientation Tuning on Recurrent Excitation and Inhibition in a Network Model of V1
One major role of primary visual cortex (V1) in vision is the encoding of the orientation of lines and contours. The role of the local recurrent network in these computations is, however, still a matter of debate. To address this issue, we analyze intracellular recording data of cat V1, which combine measuring the tuning of a range of neuronal properties with a precise localization of the recor...
متن کاملDependence of Orientation Tuning on Recurrent Excitation and Inhibition in a Network Model of V1
The computational role of the local recurrent network in primary visual cortex is still a matter of debate. To address this issue, we analyze intracellular recording data of cat V1, which combine measuring the tuning of a range of neuronal properties with a precise localization of the recording sites in the orientation preference map. For the analysis, we consider a network model of Hodgkin-Hux...
متن کاملfMRI orientation decoding in V1 does not require global maps or globally coherent orientation stimuli
The orientation of a large grating can be decoded from V1 functional magnetic resonance imaging (fMRI) data, even at low resolution (3-mm isotropic voxels). This finding has suggested that columnar-level neuronal information might be accessible to fMRI at 3T. However, orientation decodability might alternatively arise from global orientation-preference maps. Such global maps across V1 could res...
متن کاملMarket Oriented or Not: A Gender Situation Analyses of Small Holder Sweet potato Farmers in South East Nigeria
Farmers can only be market oriented if his/her production plan follows market signals and produce commodities that is more marketable. In other to achieve this, this study provided empirical evidence on the Gender analyses of market orientation in South Eastern, Nigeria. A stratified sampling design was used to select 360 sample respondents in 2017. Market Orientation Index (MOI) and Heckit sel...
متن کاملEncoding multiple orientations in a recurrent network
Models containing recurrent connections amongst the cells within a population can account for a range of empirical data on orientation selectivity in striate cortex. However, existing recurrent models are unable to veridically encode more than one orientation at a time. Underlying this inability is an inherent limitation in the variety of activity pro"les that can be stably maintained. We propo...
متن کامل