4,394 research outputs found
Gamma-ray bursts and X-ray melting of material as a potential source of chondrules and planets
The intense radiation from a gamma-ray burst (GRB) is shown to be capable of
melting stony material at distances up to 300 light years which subsequently
cool to form chondrules. These conditions were created in the laboratory for
the first time when millimeter sized pellets were placed in a vacuum chamber in
the white synchrotron beam at the European Synchrotron Radiation Facility
(ESRF). The pellets were rapidly heated in the X-ray and gamma-ray furnace to
above 1400 C melted and cooled. This process heats from the inside unlike
normal furnaces. The melted spherical samples were examined with a range of
techniques and found to have microstructural properties similar to the
chondrules that come from meteorites. This experiment demonstrates that GRBs
can melt precursor material to form chondrules that may subsequently influence
the formation of planets. This work extends the field of laboratory
astrophysics to include high power synchrotron sources.Comment: 8 pages, 10 figures. Proceedings of the 5th INTEGRAL Workshop, Munich
16-20 February 2004. High resolution figures available at
http://bermuda.ucd.ie/%7Esmcbreen/papers/duggan_01.pd
Introducing recent medical graduates as members of Script Concordance Test expert reference panels: what impact?
Published: 08/08/2016The Script Concordance Test (SCT) is being increasingly used in professional development in clinical reasoning, with linear progression in performance in SCTâs observed with increasing clinical experience. One of the limiting factors for the SCT is potential burnout in expert reference panel (ERP) members, which we have attempted to address by the introduction of recent medical graduates as panel members. We sought to evaluate the effect of introducing recent medical graduates in to our ERPâs on pass/fail decisions in the final clinical reasoning examination of the 6-year undergraduate program of the University of Adelaide, Australia. We engaged an ERP comprising 50 faculty members from three collaborating universities and 13 recent medical graduates to answer on line an identical 20 case scenario, 50 question multidisciplinary SCT twice 6 months apart. The questions were used in high stakes end of year assessment of 5th year medical students (n=132). The pass mark set by the experienced, specialist members of the panel was 49.6% and this increased to 50.4% by addition of recent medical graduates to the panel. This difference would have had no effect on fail rates estimated from the data from the cohort of 132 medical student candidates. In the context of assessment of clinical reasoning in medical programs, recent medical graduates are suitable members of SCT ERPâs, and their contribution can enrich the panel and might help to minimise risk of burnout of more experienced faculty.Paul Duggan, Bernard Charli
mytune: webvisualization technologies for Irish traditional music archives
Online digital music libraries have become important repositories
for music for all enthusiasts of Irish traditional music. These
libraries have certainly facilitated the discovery of new material
and enabled extensive exploration of musical variations on wellknown favorites. Current web interfaces to these repositories,
offer a combination of text and notation-based information as well
as providing audio and midi listening formats. However, these
interfaces could take advantage of more recently available
technologies offering graph-based, interactive, visual displays and
more useful data analytic content. Drawing on the state-of the-art
data visualization web libraries, the objective of this work is to
present a prototype of a new digital library for Irish traditional
music. The design and architecture is detailed using standard
Unified Modelling Language (UML) notation. Evaluation is
carried out by a usability survey to determine the effectiveness of
the enhancements
Bi-cultural, bi-national benchmarking and assessment of clinical reasoning in Obstetrics and Gynaecology
Abstract Background: The Script Concordance Test (SCT) is being increasingly used in professional development in clinical reasoning (CR) in postgraduate medicine. On-line delivery favours multi-institutional collaboration
Bi-cultural bi-national benchmarking and assessment of clinical reasoning in Obstetrics and Gynaecology
Published: 23/06/2016Background: The Script Concordance Test (SCT) is being increasingly used in professional development in clinical reasoning (CR) in postgraduate medicine. On-line delivery favours multi-institutional collaboration. Objectives: To establish if: 1) SCT questions developed in the French-speaking University of Montreal were readily adaptable for use in the English-speaking University of Adelaide 2) expert reference panels (ERP) from both institutions could be used interchangeably 3) student cohorts would perform similarly in the same test. Study Design: 82 SCT questions based on 27 clinical cases in Obstetrics and Gynaecology were developed in Montreal and run in a volunteer cohort of year 3 and year 4 medical students (n=154). Local faculty translated all questions, selecting 31 based on 17 clinical cases for use in summative examinations a year 5 student cohort in Adelaide (n=123). Results: Mean (SD) percentage scores using each ERP key were: 74.2 (6.4) versus 73.3 (6.9), p<0.001 for Adelaide students and 72.5 (7.8) versus 70.6 (8.8), p<0.001 for Montreal students. The correlation coefficients were â„ 0.928 (p<0.001). Conclusions: Student cohorts performed similarly regardless of which ERP key was used. With appropriate editorial control, SCTâs can be effectively shared between French and English-speaking institutions located in different hemispheres. Potential advantages include the creation of an international database of assessment items, benchmarking and cost sharing.Paul Duggan, Patricia Monnier, Alphonse Roex, Marie-JosĂ©e BĂ©dard, Bernard Charli
The Broad Absorption Line Tidal Disruption Event iPTF15af: Optical and Ultraviolet Evolution
We present multi-wavelength observations of the tidal disruption event (TDE)
iPTF15af, discovered by the intermediate Palomar Transient Factory (iPTF)
survey at redshift . The optical and ultraviolet (UV) light curves
of the transient show a slow decay over five months, in agreement with previous
optically discovered TDEs. It also has a comparable black-body peak luminosity
of erg/s. The inferred temperature
from the optical and UV data shows a value of (35) K. The
transient is not detected in X-rays up to erg/s within
the first five months after discovery. The optical spectra exhibit two distinct
broad emission lines in the He II region, and at later times also H
emission. Additionally, emission from [N III] and [O III] is detected, likely
produced by the Bowen fluorescence effect. UV spectra reveal broad emission and
absorption lines associated with high-ionization states of N V, C IV, Si IV,
and possibly P V. These features, analogous to those of broad absorption line
quasars (BAL QSOs), require an absorber with column densities cm. This optically thick gas would also explain the
non-detection in soft X-rays. The profile of the absorption lines with the
highest column density material at the largest velocity is opposite that of BAL
QSOs. We suggest that radiation pressure generated by the TDE flare at early
times could have provided the initial acceleration mechanism for this gas.
Spectral UV line monitoring of future TDEs could test this proposal.Comment: 20 pages, 12 figures, published in Ap
Time to reflect is a rare and valued opportunity; a pilot of the NIDUS-professional dementia training intervention for homecare workers during the Covid-19 pandemic
Most people living with dementia want to continue living in their own home for as long as possible and many rely on support from homecare services to do so. There are concerns that homecare often fails to meet the needs of clients with dementia, but there is limited evidence regarding effective interventions to improve its delivery for this client group. We aimed to assess whether a coâdesigned, 6âsession dementia training intervention for homecare workers (NIDUSâprofessional) was acceptable and feasible. Facilitated training sessions were delivered over 3Â months, followed by 3, monthly implementation meetings to embed changes in practice. Two trained and supervised facilitators without clinical qualifications delivered the intervention via group videoâcalls during Oct 2020âMarch 2021 to a group of seven homecare workers from one agency in England. Participants provided qualitative feedback 3â and 6âmonths post intervention. Qualitative interview data and facilitator notes were integrated in a thematic analysis. Adherence to the intervention and fidelity of delivery were high, indicating that it was acceptable and feasible to deliver in practice. Thirty of a possible 42 (71.4%) group sessions were attended. In our thematic analysis we report one overâarching theme: âHaving time and space to reflect is a rare opportunityâ. Within this we identified four subthemes (Having time to reflect is a rare opportunity; Reflecting with peers enhances learning; Reflection and perspective taking can improve care; Recognising skills and building confidence) through which we explored how participants valued the intervention to discuss their work and learn new skills. Attendance was lower for the implementation sessions, perhaps reflecting participantsâ lack of clarity about their purpose. We used our findings to consider how we can maintain positive impacts of the manualised sessions, so that these are translated into tangible, scalable benefits for people living with dementia and the homecare workforce. A randomised feasibility trial is underway
Excitons in type-II quantum dots: Finite offsets
Quantum size effects for an exciton attached to a spherical quantum dot are
calculated by a variational approach. The band line-ups are assumed to be
type-II with finite offsets. The dependence of the exciton binding energy upon
the dot radius and the offsets is studied for different sets of electron and
hole effective masses
Quality of medication use in primary care - mapping the problem, working to a solution: a systematic review of the literature
Background: The UK, USA and the World Health Organization have identified improved patient safety in healthcare as a priority. Medication error has been identified as one of the most frequent forms of medical error and is associated with significant medical harm. Errors are the result of the systems that produce them. In industrial settings, a range of systematic techniques have been designed to reduce error and waste. The first stage of these processes is to map out the whole system and its reliability at each stage. However, to date, studies of medication error and solutions have concentrated on individual parts of the whole system. In this paper we wished to conduct a systematic review of the literature, in order to map out the medication system with its associated errors and failures in quality, to assess the strength of the evidence and to use approaches from quality management to identify ways in which the system could be made safer.
Methods: We mapped out the medicines management system in primary care in the UK. We conducted a systematic literature review in order to refine our map of the system and to establish the quality of the research and reliability of the system.
Results: The map demonstrated that the proportion of errors in the management system for medicines in primary care is very high. Several stages of the process had error rates of 50% or more: repeat prescribing reviews, interface prescribing and communication and patient adherence. When including the efficacy of the medicine in the system, the available evidence suggested that only between 4% and 21% of patients achieved the optimum benefit from their medication. Whilst there were some limitations in the evidence base, including the error rate measurement and the sampling strategies employed, there was sufficient information to indicate the ways in which the system could be improved, using management approaches. The first step to improving the overall quality would be routine monitoring of adherence, clinical effectiveness and hospital admissions.
Conclusion: By adopting the whole system approach from a management perspective we have found where failures in quality occur in medication use in primary care in the UK, and where weaknesses occur in the associated evidence base. Quality management approaches have allowed us to develop a coherent change and research agenda in order to tackle these, so far, fairly intractable problems
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