A search for distant radio galaxies from SUMSS and NVSS: III. radio spectral energy distributions and the z-alpha correlation

This is the third in a series of papers that present observations and results for a sample of 76 ultra-steep-spectrum radio sources designed to find galaxies at high redshift. Here we present multi-frequency radio observations, from the Australia Telescope Compact Array, for a subset of 37 galaxies from the sample. Matched resolution observations at 2.3, 4.8 and 6.2GHz are presented for all galaxies, with the z<2 galaxies additionally observed at 8.6 and 18GHz. New angular size constraints are reported for 19 sources based on high resolution 4.8 and 6.2GHz observations. Functional forms for the rest-frame spectral energy distributions are derived: 89% of the sample is well characterised by a single power law, whilst the remaining 11% show some flattening toward higher frequencies: not one source shows any evidence for high frequency steepening. We discuss the implications of this result in light of the empirical correlation between redshift and spectral index seen in flux limited samples of radio galaxies. Finally, a new physical mechanism to explain the redshift -- spectral index correlation is posited: extremely steep spectrum radio galaxies in the local universe usually reside at the centres of rich galaxy clusters. We argue that if a higher fraction of radio galaxies, as a function of redshift, are located in environments with densities similar to nearby rich clusters, then this could be a natural interpretation for the correlation. We briefly outline our plans to pursue this line of investigation.Comment: MNRAS in pres

A binary system of tailed radio galaxies

We present a detailed study of a binary system of tailed radio galaxies which, along with 3C75, is the only such binary known to exist. The binary is located in a region of low galaxy density at the periphery of a poor cluster Abell S345, but lies close to the massive Horologium Reticulum supercluster. The radio sources have bent tail morphologies and show considerable meandering and wiggling along the jets, which are collimated throughout their lengths. This work presents observations of the large-scale-structure environment of the binary tailed radio sources with a view to examining the influence of large-scale flows on the morphology and dynamics of the associated radio tails. We argue that the orbital motions of the host galaxies together with tidal accelerations toward the supercluster have resulted in the complex structure seen in these radio tails.Comment: 10 pages, 9 figures, accepted for publication in MNRA

Functional or not functional; that's the question Can we predict the diagnosis functional movement disorder based on associated features?

Background and purpose Functional movement disorders (FMDs) pose a diagnostic challenge for clinicians. Over the years several associated features have been shown to be suggestive for FMDs. Which features mentioned in the literature are discriminative between FMDs and non-FMDs were examined in a large cohort. In addition, a preliminary prediction model distinguishing these disorders was developed based on differentiating features. Method Medical records of all consecutive patients who visited our hyperkinetic outpatient clinic from 2012 to 2019 were retrospectively reviewed and 12 associated features in FMDs versus non-FMDs were compared. An independentttest for age of onset and Pearson chi-squared analyses for all categorical variables were performed. Multivariate logistic regression analysis was performed to develop a preliminary predictive model for FMDs. Results A total of 874 patients were eligible for inclusion, of whom 320 had an FMD and 554 a non-FMD. Differentiating features between these groups were age of onset, sex, psychiatric history, family history, more than one motor phenotype, pain, fatigue, abrupt onset, waxing and waning over long term, and fluctuations during the day. Based on these a preliminary predictive model was computed with a discriminative value of 91%. Discussion Ten associated features are shown to be not only suggestive but also discriminative between hyperkinetic FMDs and non-FMDs. Clinicians can use these features to identify patients suspected for FMDs and can subsequently alert them to test for positive symptoms at examination. Although a first preliminary model has good predictive accuracy, further validation should be performed prospectively in a multi-center study

Understanding value creation and word-of-mouth behaviour at cultural events

Cultural value is a highly contested concept, despite its undoubted importance to practitioners and policy makers. Reseach into cultural value has, meanwhile, tended to employ a unidimensional value framework. This has hamprered the understanding of behaviour related to the word-of-mouth (WOM) communication behaviour of cultural values. This paper presents a cultural value segmentation based on a multidimensional value framework, allowing a profile of WOM behaviour (both online and offline) of each segment to be developed. The segmentation has four distinct segments of cultural consumer, each with different combinations of cultural values and WOM communication preferences. In this way, the study challenges current understandings of value creation and transfer in cultural settings. By way of practical recommendations, the study favours the use of market segmentation based on multi-dimensional value ‘constellations’, which can not only achieve better audience development but also to encourage wider WOM communication of the values in question

Radio Supernova 1987A at 843 MHz

We report the flux densities of the evolving radio source SN1987A at 843 MHz measured from observations made with the Molonglo Observatory Synthesis Telescope between 1994 September and 2000 May. The radio light curve shows that the rate of increase of the flux density jumped markedly around days 2800-3000 (i.e. in the first half of 1995), and that since then the radio evolution has been remarkably well fitted by a simple linear increase of (62.7 +- 0.5) microJansky/day. We discuss in detail the relationship between the radio light curve and the recent brightening of the system at optical wavelengths.Comment: To be published in the Astrophysical Journal, 11 pages, 4 postscript figure

Unveiling the mask on the ULIRG-to-QSO transition object [H89]1821+643 at z=0.3: a gas-poor/gas-rich galaxy merger and the implications for CO-based dynamical mass estimates

We report the detection of the CO J=1-0 emission line in [H89]1821+643, one of the most optically luminous QSOs in the local Universe and a template ULIRG-to-QSO transition object, located in a rich cool-core cluster at z=0.297. The CO emission is likely to be extended, highly asymmetric with respect to the center of the host elliptical where the QSO resides, and corresponds to a molecular gas mass of ~ 8.0 x 10^{9} M_sun. The dynamical mass enclosed by the CO line emission region could amount up to ~ 1.7x10^{12} M_sun (80% of the total mass of the elliptical host). The bulk of the CO emission is located at ~9 kpc south-east from the nuclei position, and close to a faint optical structure, suggesting that the CO emission could either represent a gas-rich companion galaxy merging with the elliptical host or a tail-like structure reminiscent of a previous interaction. We argue that the first scenario is more likely given the large masses implied for the CO source, which would imply a highly asymmetrical elliptical host. The close alignment between the CO emission major axis and the radio-plume suggests a possible role of the latter excitation of the ambient gas reservoir. The stacking technique was used to search for CO emission and 3mm continuum emission from galaxies in the surrounding cluster, however no detection was found either toward individual galaxies or the stacked ensemble of galaxies, with a 3 sigma limit of < 1.1x10^9 M_sun for the molecular gas.Comment: Accepted for publication in the Astrophysical Journal; replaced title revise

On the Spectral Index of Distant Radio Galaxies

The problems of using the spectral index of radio galaxies in various tests, in particular, in selecting distant radio sources are considered. The history of the question of choosing a criterion of searching for distant radio galaxies based on the spectral index is presented. For a new catalog of 2442 radio galaxies constructed from NED, SDSS, and CATS data, an analytical form of the sp ectral index.redshift relation has been determined for the first time. The spectral index.angular size and spectral index.flux density diagrams have also been constructed. Peculiarities of the distribution of sources on these diagrams are discussed.Comment: 7 pages,5 figure

Resolved Dust Emission in a Quasar at z=3.65

We present submillimetre observations of the z=3.653 quasar SDSS160705+533558 together with data in the optical and infrared. The object is unusually bright in the far-IR and submm with an IR luminosity of ~10^14 L_sun. We ascribe this luminosity to a combination of AGN and starburst emission, with the starburst forming stars at a rate of a few thousand solar masses per year. Submillimetre Array (SMA) imaging observations with a resolution ~1" show that the submm (850 micron) emission is extended on scales of 10--35kpc and is offset from the optical position by ~10 kpc. This morphology is dissimilar to that found in submm galaxies, which are generally un- or marginally resolved on arcsecond scales, or submm-luminous AGN where the AGN lies at the peak of the submm or molecular emission. The simplest explanation is that the object is in the early stages of a merger between a gas rich galaxy, which hosts the starburst, and a gas-poor AGN-host galaxy, which is responsible for the quasar emission. It is also possible that jet induced star formation might contribute to the unusual morphology.Comment: ApJ Letters, in pres

International Veterinary Epilepsy Task Force Consensus Proposal: Outcome of therapeutic interventions in canine and feline epilepsy

Common criteria for the diagnosis of drug resistance and the assessment of outcome are needed urgently as a prerequisite for standardized evaluation and reporting of individual therapeutic responses in canine epilepsy. Thus, we provide a proposal for the definition of drug resistance and partial therapeutic success in canine patients with epilepsy. This consensus statement also suggests a list of factors and aspects of outcome, which should be considered in addition to the impact on seizures. Moreover, these expert recommendations discuss criteria which determine the validity and informative value of a therapeutic trial in an individual patient and also suggest the application of individual outcome criteria. Agreement on common guidelines does not only render a basis for future optimization of individual patient management, but is also a presupposition for the design and implementation of clinical studies with highly standardized inclusion and exclusion criteria. Respective standardization will improve the comparability of findings from different studies and renders an improved basis for multicenter studies. Therefore, this proposal provides an in-depth discussion of the implications of outcome criteria for clinical studies. In particular ethical aspects and the different options for study design and application of individual patient-centered outcome criteria are considered