CT head reporting by radiographers: Findings of an accredited postgraduate programme

Content of Presentation: Reporting by radiographers is now widely adopted into the service delivery of English NHS trusts. CT Head reporting courses have been running since the early 2000’s, and has been running at Canterbury Christ Church University since 2007. Relevance: To analyse the objective structured examination (OSE) results of the last four cohorts of radiographers (n=24) who successfully completed the postgraduate training. Outcomes: Using OSE scores of Agreement, Sensitivity and Specificity and using Kappa agreement of scores for comparison to 3 groups of consultant radiologists who produced the initial OSE reports. The cases contained a prevalence of 50% abnormal cases and 50% normal cases. Discussion: At the end of this study of training, radiographers appear to achieve high standards of CT head reporting. The findings for this study suggest that the agreement rates for appropriately educated and trained radiographers is likely to be similar to consultant radiologists, although further work is on-going to investigate this, and confirm the clinical application of these initial encouraging findings that support the radiographers contribution to this aspect of the reporting service

A numerical model of the ionospheric signatures of time-varying magneticreconnection: I. ionospheric convection

This paper presents a numerical model for predicting the evolution of the pattern of ionospheric convection in response to general time-dependent magnetic reconnection at the dayside magnetopause and in the cross-tail current sheet of the geomagnetic tail. The model quantifies the concepts of ionospheric flow excitation by Cowley and Lockwood (1992), assuming a uniform spatial distribution of ionospheric conductivity. The model is demonstrated using an example in which travelling reconnection pulses commence near noon and then move across the dayside magnetopause towards both dawn and dusk. Two such pulses, 8 min apart, are used and each causes the reconnection to be active for 1 min at every MLT that they pass over. This example demonstrates how the convection response to a given change in the interplanetary magnetic field (via the reconnection rate) depends on the previous reconnection history. The causes of this effect are explained. The inherent assumptions and the potential applications of the model are discussed

The dependence of cusp ion signatures on the reconnection rate

The interpretation of structure in cusp ion dispersions is important for helping to understand the temporal and spatial structure of magnetopause reconnection. “Stepped” and “sawtooth” signatures have been shown to be caused by temporal variations in the reconnection rate under the same physical conditions for different satellite trajectories. The present paper shows that even for a single satellite path, a change in the amplitude of any reconnection pulses can alter the observed signature and even turn sawtooth into stepped forms and vice versa. On 20 August 1998, the Defense Meteorological Satellite Program (DMSP) craft F-14 crossed the cusp just to the south of Longyearbyen, returning on the following orbit. The two passes by the DMSP F-14 satellites have very similar trajectories and the open-closed field line boundary (OCB) crossings, as estimated from the SSJ/4 precipitating particle data and Polar UVI images, imply a similarly-shaped polar cap, yet the cusp ion dispersion signatures differ substantially. The cusp crossing at 08:54 UT displays a stepped ion dispersion previously considered to be typical of a meridional pass, whereas the crossing at 10:38 UT is a sawtooth form ion dispersion, previously considered typical of a satellite travelling longitudinally with respect to the OCB. It is shown that this change in dispersed ion signature is likely to be due to a change in the amplitude of the pulses in the reconnection rate, causing the stepped signature. Modelling of the low-energy ion cutoff under different conditions has reproduced the forms of signature observed

A numerical model of the ionospheric signatures of time-varying magnetic reconnection: II. Measuring expansions in the ionospheric flow response

A numerical model embodying the concepts of the Cowley-Lockwood (Cowley and Lockwood, 1992, 1997) paradigm has been used to produce a simple Cowley– Lockwood type expanding flow pattern and to calculate the resulting change in ion temperature. Cross-correlation, fixed threshold analysis and threshold relative to peak are used to determine the phase speed of the change in convection pattern, in response to a change in applied reconnection. Each of these methods fails to fully recover the expansion of the onset of the convection response that is inherent in the simulations. The results of this study indicate that any expansion of the convection pattern will be best observed in time-series data using a threshold which is a fixed fraction of the peak response. We show that these methods used to determine the expansion velocity can be used to discriminate between the two main models for the convection response to a change in reconnection

Modeling the observed proton aurora and ionospheric convection responses to changes in the IMF clock angle: 1. Persistence of cusp proton aurora

We employ a numerical model of cusp ion precipitation and proton aurora emission to fit variations of the peak Doppler-shifted Lyman-a intensity observed on 26 November 2000 by the SI-12 channel of the FUV instrument on the IMAGE satellite. The major features of this event appeared in response to two brief swings of the interplanetary magnetic field (IMF) toward a southward orientation. We reproduce the observed spatial distributions of this emission on newly opened field lines by combining the proton emission model with a model of the response of ionospheric convection. The simulations are based on the observed variations of the solar wind proton temperature and concentration and the interplanetary magnetic field clock angle. They also allow for the efficiency, sampling rate, integration time and spatial resolution of the FUV instrument. The good match (correlation coefficient 0.91, significant at the 98% level) between observed and modeled variations confirms the time constant (about 4 min) for the rise and decay of the proton emissions predicted by the model for southward IMF conditions. The implications for the detection of pulsed magnetopause reconnection using proton aurora are discussed for a range of interplanetary conditions

Intraorbital foreign body detection and localisation by radiographers: a preliminary JAFROC observer performance study

Introduction - The purpose of this study was to run a preliminary investigation to establish if a short course of learning would increase radiographers’ performance in intraorbital foreign body (IOFB) detection and localisation on pre-magnetic resonance imaging (MRI) orbital computed radiographs (CR). Method - A multi-reader multi-case (MRMC) human observer study was performed. Fifteen radiographers from 5 hospitals participated. Each radiographer reviewed a pre- and post-training image bank and was instructed to identify the presence or absence of IOFBs, indicating the lesion location on each case whilst scoring the detection using a confidence index on a 5-point scale, for 30 orbital radiographs. The results were analysed using a Jackknife free-response receiver operating characteristic (JAFROC2 equal weighted) methodology. Results -The performance of the radiographers demonstrated a statistically significant difference after a short period of training in the detection of IOFBs on orbital radiographs (F (1,14)= 12.99, df = 14.0, p = 0.0029). The JAFROC2 analysis averaged figure of merit (FOM) for the radiographers was 0.818 (95% CI 0.769, 0.867) pre-training and 0.920 (95% CI 0.891, 0.950) post-training. Conclusion - These results suggest that with a short programme of learning in image interpretation for IOFBs in orbital radiographs, radiographers should be able to achieve a high level of accuracy in the identification and localisation of IOFBs prior to MRI examination

Asylum support for children and young people living in Kirklees : stories of mothers

Executive Summary The report is based on a one-year pilot study by academic practitioners at WomenCentre, Kirklees, funded by the Nationwide Children’s Research Centre. This study has taken a localised approach to the Parliamentary Inquiry (2013) into asylum support for children and young people. We have placed the views of mothers of children who live or have lived in receipt of asylum support in Kirklees at the heart of the study. All of the mothers interviewed said that asylum support (accommodation and/or financial subsistence) was or had been their only means of survival and many of them have spent several years in receipt of asylum support with their children. Using the themes that arose in the ‘Parliamentary Inquiry into asylum support for children and young people (2013)’, we have examined the mothers’ accounts of asylum support in relation to children and young people living in Kirklees. Consistent with the Parliamentary Inquiry and central to the analysis, a number of areas of concern were raised by the mothers: ‘essential living needs’, ‘home-life’, ‘education’ and ‘societal attitudes’. A further theme emerged around ‘children’s resilience’. As part of this report we have presented the recommendations put forward by the mothers: • Families seeking asylum should be given the right to work. • Section 4 support should be abolished and a cash-based support system introduced for all children, young people and their families. • Families should have a choice about where they live. • The best interests of the child should be central to decision affecting children.<br/

Cosmic ray modulation of infra-red radiation in the atmosphere

Cosmic rays produce molecular cluster ions as they pass through the lower atmosphere. Neutral molecular clusters such as dimers and complexes are expected to make a small contribution to the radiative balance, but atmospheric absorption by charged clusters has not hitherto been observed. In an atmospheric experiment, a narrowband thermopile filter radiometer centred on 9.15 {\mu}m, an absorption band previously associated with infra-red absorption of molecular cluster ions, was used to monitor changes following events identified by a cosmic ray telescope sensitive to high-energy (>400 MeV) particles, principally muons. The average change in longwave radiation in this absorption band due to molecular cluster ions is 7 mWm sup{-2}. The integrated atmospheric energy density for each event is 2 Jm sup{-2}, representing an amplification factor of 10 sup{12} compared to the estimated energy density of a typical air shower. This absorption is expected to occur continuously and globally, but calculations suggest that it has only a small effect on climate