Ultrasound Clinical Teaching Capacity in England: A Scoping Exercise

Introduction The United Kingdom has a sonographer shortage. Health Education England are working with stakeholders to address these shortages and increase clinical capacity for sonographer education. The aims of this survey were to ascertain current sonographer staffing levels, estimate staffing requirements in five years’ time and review current clinical placement capacity. Methods An on-line survey was used to explore the aims of the study. Questions included current and predicted sonographer staffing requirements and clinical capacity for teaching ultrasound. Free text comments were available for expanding on responses. Results Of 72 completed responses the mean sonographer vacancy rate was 2.65 and the predicted number of sonographers needed to provide the service in five years was 4.6. Departments were teaching an average of two sonographers and 2 non-sonographers. A small number of departments had further capacity for sonography student training which was not being utilised for reasons including limited capacity, inadequate staffing levels or competing demands of teaching other health care professionals. Extended working days and weekend training lists were used to increase capacity, along with rolling programmes for teaching sonographers and the use of simulation. Conclusion The survey supported previous publications that have shown sonographer shortages in England and this is predicted to increase over the next five years. Departments were teaching a similar number of sonographers as other health care professionals. Many experienced competing demands, which challenged their ability to increase clinical capacity. Implications for practice Suggestions for increasing capacity are provided to help grow the sonography workforce. With the advent of new sonography programmes at direct entry, the departments with spare capacity could be utilised to support clinical placements for sonography students in need of a placement on a direct entry programme

A search for thermal X-ray signatures in Gamma-Ray Bursts I: Swift bursts with optical supernovae

The X-ray spectra of Gamma-Ray Bursts can generally be described by an absorbed power law. The landmark discovery of thermal X-ray emission in addition to the power law in the unusual GRB 060218, followed by a similar discovery in GRB 100316D, showed that during the first thousand seconds after trigger the soft X-ray spectra can be complex. Both the origin and prevalence of such spectral components still evade understanding, particularly after the discovery of thermal X-ray emission in the classical GRB 090618. Possibly most importantly, these three objects are all associated with optical supernovae, begging the question of whether the thermal X-ray components could be a result of the GRB-SN connection, possibly in the shock breakout. We therefore performed a search for blackbody components in the early Swift X-ray spectra of 11 GRBs that have or may have associated optical supernovae, accurately recovering the thermal components reported in the literature for GRBs 060218, 090618 and 100316D. We present the discovery of a cooling blackbody in GRB 101219B/SN2010ma, and in four further GRB-SNe we find an improvement in the fit with a blackbody which we deem possible blackbody candidates due to case-specific caveats. All the possible new blackbody components we report lie at the high end of the luminosity and radius distribution. GRB 101219B appears to bridge the gap between the low-luminosity and the classical GRB-SNe with thermal emission, and following the blackbody evolution we derive an expansion velocity for this source of order 0.4c. We discuss potential origins for the thermal X-ray emission in our sample, including a cocoon model which we find can accommodate the more extreme physical parameters implied by many of our model fits.Comment: 16 pages, 6 figures, accepted for MNRA

Direct simulation of ion beam induced stressing and amorphization of silicon

Using molecular dynamics (MD) simulation, we investigate the mechanical response of silicon to high dose ion-irradiation. We employ a realistic and efficient model to directly simulate ion beam induced amorphization. Structural properties of the amorphized sample are compared with experimental data and results of other simulation studies. We find the behavior of the irradiated material is related to the rate at which it can relax. Depending upon the ability to deform, we observe either the generation of a high compressive stress and subsequent expansion of the material, or generation of tensile stress and densification. We note that statistical material properties, such as radial distribution functions are not sufficient to differentiate between different densities of amorphous samples. For any reasonable deformation rate, we observe an expansion of the target upon amorphization in agreement with experimental observations. This is in contrast to simulations of quenching which usually result in denser structures relative to crystalline Si. We conclude that although there is substantial agreement between experimental measurements and most simulation results, the amorphous structures being investigated may have fundamental differences; the difference in density can be attributed to local defects within the amorphous network. Finally we show that annealing simulations of our amorphized samples can lead to a reduction of high energy local defects without a large scale rearrangement of the amorphous network. This supports the proposal that defects in amorphous silicon are analogous to those in crystalline silicon.Comment: 13 pages, 12 figure

Exploring the Experiences of Dis/abled STEM Graduate Students

It is essential to include all individuals who can contribute to research, education, and society, especially those from diverse backgrounds and abilities. Yet dis/abled graduate students have been ignored in institutional policies, departmental practices, instruction, advising, and research. Responding to this gap in knowledge, I explore the experiences of seven Science, Technology, Engineering, and Mathematics (STEM) graduate students with less apparent dis/abilities. The study included two sequential phases of data collection through virtual interviews and qualitative analysis of the participant responses. I chose to highlight three topics in my dissertation: alienation, the culture of productivity, and interpersonal relationships. This dissertation explores the participants&rsquo; Stories (spelled with a capital S) and the impacts of these phenomena on their professional advancement, social relationships, well-being, health, and academics. It also offers opportunities to broaden awareness; challenge bias and violence; honor student agency; emancipate learners and educators from systems of oppression; support the supporters; and share resources and opportunities.</p

On the X-ray variability of magnetar 1RXS J170849.0-400910

We present a long-term X-ray flux and spectral analysis for 1RXS J170849.0-400910 using Swift/XRT spanning over 8 years from 2005-2013. We also analyze two observations from Chandra and XMM in the period from 2003-2004. In this 10-yr period, 1RXS J170849.0-400910 displayed several rotational glitches. Previous studies have claimed variations in the X-ray emission associated with some of the glitches. From our analysis we find no evidence for significant X-ray flux variations and evidence for only low-level spectral variations. We also present an updated timing solution for 1RXS J170849.0-400910, from RXTE and Swift observations, which includes a previously unreported glitch at MJD 56019. We discuss the frequency and implications of radiatively quiet glitches in magnetars.Comment: 9 pages, 2 figures, accepted for publication in Ap

Kinase inhibition leads to hormesis in a dual phosphorylation-dephosphorylation cycle

This is the final version of the article. Available from the publisher via the DOI in this record.Many antimicrobial and anti-tumour drugs elicit hormetic responses characterised by low-dose stimulation and high-dose inhibition. While this can have profound consequences for human health, with low drug concentrations actually stimulating pathogen or tumour growth, the mechanistic understanding behind such responses is still lacking. We propose a novel, simple but general mechanism that could give rise to hormesis in systems where an inhibitor acts on an enzyme. At its core is one of the basic building blocks in intracellular signalling, the dual phosphorylation-dephosphorylation motif, found in diverse regulatory processes including control of cell proliferation and programmed cell death. Our analytically-derived conditions for observing hormesis provide clues as to why this mechanism has not been previously identified. Current mathematical models regularly make simplifying assumptions that lack empirical support but inadvertently preclude the observation of hormesis. In addition, due to the inherent population heterogeneities, the presence of hormesis is likely to be masked in empirical population-level studies. Therefore, examining hormetic responses at single-cell level coupled with improved mathematical models could substantially enhance detection and mechanistic understanding of hormesis.Funding bodies: BBSRC (BB/J010340/1); EPSRC (EP/I00503X/1); Wellcome Trust (ISSF to University of Exeter)

Alternative evolutionary paths to bacterial antibiotic resistance cause distinct collateral effects.

Published onlineJournal ArticleThis is the author accepted manuscript. The final version is available from Oxford University Press via the DOI in this record.When bacteria evolve resistance against a particular antibiotic, they may simultaneously gain increased sensitivity against a second one. Such collateral sensitivity may be exploited to develop novel, sustainable antibiotic treatment strategies aimed at containing the current, dramatic spread of drug resistance. To date, the presence and molecular basis of collateral sensitivity has only been studied in few bacterial species and is unknown for opportunistic human pathogens such as Pseudomonas aeruginosa. In the present study, we assessed patterns of collateral effects by experimentally evolving 160 independent populations of P. aeruginosa to high levels of resistance against eight commonly used antibiotics. The bacteria evolved resistance rapidly and expressed both collateral sensitivity and cross-resistance. The pattern of such collateral effects differed to those previously reported for other bacterial species, suggesting inter-specific differences in the underlying evolutionary trade-offs. Intriguingly, we also identified contrasting patterns of collateral sensitivity and cross-resistance among the replicate populations adapted to the same drug. Whole-genome sequencing of 81 independently evolved populations revealed distinct evolutionary paths of resistance to the selective drug, which determined whether bacteria became cross-resistant or collaterally sensitive towards others. Based on genomic and functional genetic analysis, we demonstrate that collateral sensitivity can result from resistance mutations in regulatory genes such as nalC or mexZ, which mediate aminoglycoside sensitivity in β-lactam-adapted populations, or the two-component regulatory system gene pmrB, which enhances penicillin sensitivity in gentamicin-resistant populations. Our findings highlight substantial variation in the evolved collateral effects among replicates, which in turn determine their potential in antibiotic therapy.We thank Anette Friedrichs, Lutz Becks, and the Schulenburg group for valuable advice and Melanie Vollstedt for technical support during genome sequencing. We are grateful for financial support from the German Science Foundation (DFG grant SCHU 1415/12-1) and the International Max-Planck Research School for Evolutionary Biology at the University of Kiel. We acknowledge infrastructural support by the DFG excellence cluster Inflammation at Interfaces

Competency level in radiotherapy across EU educational programmes: A cross-case study evaluating stakeholders' perceptions

Introduction: The education of Therapeutic Radiographers (TRs) is regulated in some countries but is not standardised across the EU, leading to differences in competencies between and within member states. This study aimed to explore stakeholders’ perceptions regarding underdeveloped competencies of TRs practising on the linear accelerator, identified in a previous study by the same research team.Methods: Interviews with stakeholders from four countries (selected based on the characteristics of their degrees) were performed as part of this cross-case study. Stakeholders were asked to provide their perception regarding the least developed competencies identified in a previous study.Results: The 27 stakeholders confirmed that Pharmacology, Quality Assurance (QA), Management and Leadership, Research (from the previous study) were underdeveloped and identified Image Verification and Critical Thinking as additional underdeveloped competencies. Suggested causes included: lack of regulation of required competencies at the national level, lack of training dedicated to radiotherapy (RT) (taught within generic modules) and lack of time within the degree programme. The ideal academic level to develop these competencies and whether they are essential varied between country and stakeholder.Conclusion: It is essential to regulate learning outcomes at the national level to ensure a high level of care is provided to all RT patients and, ideally, standardise it across Europe. Education institutions should review their curricula to ensure that sufficient time is dedicated to RT and that the essential competencies are developed. Due to time constraints within some programmes, some competencies must be developed after graduation.Implications for practice: Lack of regulation of learning outcomes (at European level and national level in many countries) and lack of RT-specific training lead to underdeveloped competencies that may compromise patient care.peer-reviewe