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The remnant phase of a radio galaxy begins when the jets launched from an active galactic nucleus are switched off. To study the fraction of radio galaxies in a remnant phase, we take advantage of a 
$8.31$ deg
$^2$ subregion of the GAMA 23 field which comprises of surveys covering the frequency range 0.1–9 GHz. We present a sample of 104 radio galaxies compiled from observations conducted by the Murchison Widefield Array (216 MHz), the Australia Square Kilometer Array Pathfinder (887 MHz), and the Australia Telescope Compact Array (5.5 GHz). We adopt an ‘absent radio core’ criterion to identify 10 radio galaxies showing no evidence for an active nucleus. We classify these as new candidate remnant radio galaxies. Seven of these objects still display compact emitting regions within the lobes at 5.5 GHz; at this frequency the emission is short-lived, implying a recent jet switch off. On the other hand, only three show evidence of aged lobe plasma by the presence of an ultra-steep-spectrum (
$\alpha<-1.2$) and a diffuse, low surface brightness radio morphology. The predominant fraction of young remnants is consistent with a rapid fading during the remnant phase. Within our sample of radio galaxies, our observations constrain the remnant fraction to 
$4\%\lesssim f_{\mathrm{rem}} \lesssim 10\%$; the lower limit comes from the limiting case in which all remnant candidates with hotspots are simply active radio galaxies with faint, undetected radio cores. Finally, we model the synchrotron spectrum arising from a hotspot to show they can persist for 5–10 Myr at 5.5 GHz after the jets switch of—radio emission arising from such hotspots can therefore be expected in an appreciable fraction of genuine remnants.
Fig. 1
[Improvement in daily accessible risk assessments]
We show enhanced patient safety through a quality improvement methodology project in an intensive psychiatric care unit of a psychiatric hospital in southwest of Scotland. This is a project as part of the national patient safety programme in mental health. The Scottish Patient Safety Programme for Mental Health aims to systematically reduce harm experienced by people using mental health services in Scotland, by supporting frontline staff to test, gather real-time data and reliably implement interventions, before spreading across their catchment area.
Multidisciplinary staff worked together in improving recording of daily electronic and paper based risk assessments from a baseline of 20% to nearly 100% over a sixth month period. We expect better quality risk management by readily accessible risk assessments and safe practise through enhanced safety perception by the patients as well as staff. Patient and staff safety perception tools were designed to measure impact of improvement in risk management. We have seen drop in the number of critical incidents and challenging situations requiring restraint following coordinated approach to risk assessment and easy access to key information. We have been successful as the frontline staff became part of the process of change and this has enabled sustained improvement.
