Hard X-ray and radio studies of solar flares

Combined X-ray and radio observations of the Sun provide powerful diagnostics of particle acceleration and transport effects during solar flares. In this thesis we present observations of two solar flares. In the first event we report what we believe to be the first observation of hard X-ray emission formed in a coronal, flare-related jet. Occurring on the 22nd of August 2002, the event was observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Nobeyama Radioheliograph (NoRH) and Polarimeters (NoRP). During the impulsive phase RHESSI observed significant hard X-ray emission to energies as high as 30-50 keV in the jet. RHESSI spectroscopy shows a powerlaw spectrum with a spectral index of ~4 and NoRH images reveal radio emission at 17 GHz and 34 GHz co-spatial with the hard X-ray emission, thus supporting the evidence for nonthermal emission in the jet. The second event occurred on the 24th of August 2002 and was also observed by RHESSI and NoRH. The size and orientation of the flare, which occurred on the west limb of the Sun, make it particularly interesting to study. At both NoRH frequencies emission is observed at all points along a flare loop such that the looptop and footpoint emission are clearly separated. We present observations of the flare decay phase to investigate the long term evolution of the event. In particular we follow the evolution of relevant plasma parameters which are used as an input to a 3D gyrosynchrotron model in an attempt to reproduce the observed emission at radio wavelengths

Concert to launch 1992 in dedication to Johnny Dyani, Mongezi Feza, Chris McGregor, Harry Miller and Dudu Pukwana

Original poster for a concert in dedication to Johnny Dyani, Mongezi Feza, Chris McGregor, Harry Miller, Dudu Pukwana by Spirits Rejoice and the Dedication Orchestra at the 100 Club, London

Attainment and transition experiences of students progressing from an evening access programme to undergraduate study

The under-representation of particular sections of society in Higher Education (HE) is a driver for the current widening participation agenda. The Scottish Government has an ambition that ‘by 2030 students from the 20 per cent most deprived backgrounds should represent 20 per cent of entrants to higher education’ (COWA, 2016). However, there is recognition that in order to achieve this target there may need to be a range of entry routes and contextual offers available. According to Scottish government figures, Abertay is one of Scotland’sleading HE centres for wider access (SFC, 2016). The university has offered a free part-time evening access course (Access to Higher Education Abertay Dundee (AHEAD) for a number of years but it underwent significant restructuring in 2012. This study considers the progression, attainment and experiences of students transitioning from the revised access route to their chosen undergraduate degree programme and through subsequent stages of study

A Dialogue of Forms: The Display of Thinking in George Eliot’s ‘Poetry and Prose, From the Notebook of an Eccentric’ and Impressions of Theophrastus Such

This article rereads George Eliot's Impressions of Theophrastus Such in the light of her early series of journalism “Poetry and Prose, from the Notebook of an Eccentric.” Rather than viewing these texts as experimental deviations, this article casts these texts as part of larger patterns evident in Eliot's canon as a whole. Building on recent studies on Eliot and Victorian perfectionism, it argues that Eliot united an appreciation for complex and diverse configurations of form with her interest in individual development and the extension of sympathy. In these texts, we can see a reflection of Eliot's interest in the attempt to capture and display human thinking processes in order to advance her project of extending the sympathies of her readership. It examines Eliot's organicist views on form and consciousness and suggests that these are key to making sense of the apparently “aberrant” nature of these texts. Eliot, influenced by Ludwig Feuerbach, held to the idea that just as the highest form of organicism was the most complex, so also was the highest form of art the most structurally varied and intricate. From this viewpoint, the texts are eminently successful. Moreover, they point the way to achieving a fuller understanding of the apparent problematics of form that have concerned critics in regard to Eliot's better-known fictional works since their original publication

The Effect of Agenda for Change on the Career Progression of the Radiographic Workforce 2009

Report compiled by the University of Hertfordshire in collaboration with the Inst for Employment Studies and Oxford Radcliffe Hospitals NHS Trust for the Society and College of RadiographersFinal Published versio

Evaluation of delirium screening tools in geriatric medical inpatients: a diagnostic test accuracy study

Introduction: screening all unscheduled older adults for delirium is recommended in national guidelines, but there is no consensus on how to perform initial assessment. Aim: to evaluate the test accuracy of five brief cognitive assessment tools for delirium diagnosis in routine clinical practice. Methods: a consecutive cohort of non-elective, elderly care (older than 65 years) hospital inpatients admitted to a geriatric medical assessment unit of an urban teaching hospital. Reference assessments were clinical diagnosis of delirium performed by elderly care physicians. Routine screening tests were: Abbreviated Mental Test (AMT-10, AMT-4), 4 A's Test (4AT), brief Confusion Assessment Method (bCAM), months of the year backwards (MOTYB) and informant Single Question in Delirium (SQiD). Results: we assessed 500 patients, mean age 83 years (range = 66−101). Clinical diagnoses were: 93 of 500 (18.6%) definite delirium, 104 of 500 (20.8%) possible delirium and 277 of 500 (55.4%) no delirium; 266 of 500 (53.2%) were identified as definite or possible dementia. For diagnosis of definite delirium, AMT-4 (cut-point < 3/4) had a sensitivity of 92.7% (95% confidence interval (CI): 84.8–97.3), with a specificity of 53.7% (95% CI: 48.1–59.2); AMT-10 (<4/10), MOTYB (<4/12) and SQiD showed similar performance. bCAM had a sensitivity of 70.3% (95% CI: 58.5–80.3) with a specificity of 91.4% (95% CI: 87.7–94.3). 4AT (>4/12) had a sensitivity of 86.7% (95% CI: 77.5–93.2) and specificity of 69.5% (95% CI: 64.4–74.3). Conclusions: short screening tools such as AMT-4 or MOTYB have good sensitivity for definite delirium, but poor specificity; these tools may be reasonable as a first stage in assessment for delirium. The 4AT is feasible and appears to perform well with good sensitivity and reasonable specificity

Supporting transition:an analysis of the experience and performance of widening access students on their undergraduate degree programmes

The paper examines the experience and performance of Abertay Access to Higher Education programme, AHEAD. The research is largely based on a qualitative analysis of two focus groups and nine in-depth, semi-structured interviews with former AHEAD students. A statistical analysis of the performance of all AHEAD students on their chosen undergraduate degrees between 2012-13 and 2016-17 was also conducted. The paper demonstrates that AHEAD is an effective alternative route to higher education and argues that university-based access courses may be better in preparing these students for the culture and rigours of university life

Moving Toward Equal Ground: Engaging the Capacity of Youth, Families, and Communities to Improve Treatment Services and Outcomes in the Juvenile Justice System

Outlines RWJF's Reclaiming Futures project, describes successful programs at ten sites, and shares lessons learned about the importance of involving families and communities in improving the juvenile justice system's drug and alcohol treatment programs

Factors affecting consistency and accuracy in identifying modern macroperforate planktonic foraminifera

Planktonic foraminifera are widely used in biostratigraphic, palaeoceanographic and evolutionary studies, but the strength of many study conclusions could be weakened if taxonomic identifications are not reproducible by different workers. In this study, to assess the relative importance of a range of possible reasons for among-worker disagreement in identification, 100 specimens of 26 species of macroperforate planktonic foraminifera were selected from a core-top site in the subtropical Pacific Ocean. Twenty-three scientists at different career stages – including some with only a few days experience of planktonic foraminifera – were asked to identify each specimen to species level, and to indicate their confidence in each identification. The participants were provided with a species list and had access to additional reference materials. We use generalised linear mixed-effects models to test the relevance of three sets of factors in identification accuracy: participant-level characteristics (including experience), species-level characteristics (including a participant’s knowledge of the species) and specimen-level characteristics (size, confidence in identification). The 19 less experienced scientists achieve a median accuracy of 57 %, which rises to 75 % for specimens they are confident in. For the 4 most experienced participants, overall accuracy is 79 %, rising to 93 % when they are confident. To obtain maximum comparability and ease of analysis, everyone used a standard microscope with only 35× magnification, and each specimen was studied in isolation. Consequently, these data provide a lower limit for an estimate of consistency. Importantly, participants could largely predict whether their identifications were correct or incorrect: their own assessments of specimen-level confidence and of their previous knowledge of species concepts were the strongest predictors of accuracy

Integrated Late Eocene-Oligocene Stratigraphy of the Alabama Coastal Plain: Correlation of Hiatuses and Stratal Surfaces to Glacioeustatic Lowerings

We integrated strontium and oxygen isotopic, biostratigraphic, and magnetostratigraphic studies of two upper Eocene-Oligocene boreholes drilled near Bay Minette and St. Stephens Quarry (SSQ), Alabama. Continuous coring provided fresh, unweathered material for magnetostratigraphic studies, minimizing problems reported from nearby outcrops. Difficulties with each technique were encountered because of diagenesis, absence of marker fossils, and the presence of unconformities; however, by integrating results from isotopic stratigraphy, biostratigraphy, and magnetostratigraphy, we correlated these relatively shallow-water deposits to the geomagnetic polarity time scale (GPTS). At the SSQ borehole, the upper Eocene to lower Oligocene section is apparently complete within our stratigraphic resolution (0.2-0.5 m.y.), allowing us to estimate the ages of several stratal surfaces. Late Eocene Sr isotope age estimates are as expected at the SSQ borehole, but Oligocene ages are ~1 m.y. older than expected due to diagenesis. At the Bay Minette borehole, a latest Eocene-earliest Oligocene and a late early Oligocene hiatus were detected. We correlate these two hiatuses and stratal surfaces at SSQ with global δ^18O increases inferred to represent glacioeustatic lowerings and with evidence for hiatuses on other continental margins: (1) a distinct disconformity at the base of the Chickasawhay Limestone at both boreholes and a hiatus at Bay Minette correlates with a global δ^18O increase; we revise the age of this surface (equivalent to the TB 1.1 sequence boundary) making it ~2 m.y. older than previously reported; and (2) a surface at the top of the Shubuta Member (lowermost Oligocene) has been interpreted both as a condensed section and a disconformity; this surface at SSQ and a hiatus at Bay Minette correlate with a sharp global δ^18O increase and with hiatuses on the New Jersey and Irish margins. The timing of the hiatuses and stratal surfaces correlates with the inflection of the δ^18O increases and not with the maximum values, supporting models that indicate that unconformities form during the maximum rates of sea level fall