156 research outputs found
Interlaboratory study for coral Sr/Ca and other element/Ca ratio measurements
The Sr/Ca ratio of coral aragonite is used to reconstruct past sea surface temperature (SST). Twentyone
laboratories took part in an interlaboratory study of coral Sr/Ca measurements. Results show
interlaboratory bias can be significant, and in the extreme case could result in a range in SST estimates of
7°C. However, most of the data fall within a narrower range and the Porites coral reference material JCp-
1 is now characterized well enough to have a certified Sr/Ca value of 8.838 mmol/mol with an expanded
uncertainty of 0.089 mmol/mol following International Association of Geoanalysts (IAG) guidelines.
This uncertainty, at the 95% confidence level, equates to 1.5°C for SST estimates using Porites, so is
approaching fitness for purpose. The comparable median within laboratory error is <0.5°C. This
difference in uncertainties illustrates the interlaboratory bias component that should be reduced through
the use of reference materials like the JCp-1. There are many potential sources contributing to biases in
comparative methods but traces of Sr in Ca standards and uncertainties in reference solution composition
can account for half of the combined uncertainty. Consensus values that fulfil the requirements to be
certified values were also obtained for Mg/Ca in JCp-1 and for Sr/Ca and Mg/Ca ratios in the JCt-1 giant
clam reference material. Reference values with variable fitness for purpose have also been obtained for
Li/Ca, B/Ca, Ba/Ca, and U/Ca in both reference materials. In future, studies reporting coral element/Ca
data should also report the average value obtained for a reference material such as the JCp-1
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A genomic storm in critically injured humans
Critical injury in humans induces a genomic storm with simultaneous changes in expression of innate and adaptive immunity genes
Australia's insurance crisis and the inequitable treatment of self-employed midwives
Based upon a review of articles published in Australia's major newspapers over the period January 2001 to December 2005, a case study approach has been used to investigate why, when compared with other small business operators, including medical specialists, Australian governments have appeared reluctant to protect the economic viability of the businesses of self-employed midwives. Theories of agenda setting and structuralism have been used to explore that inequity. What has emerged is a picture of the complex of factors that may have operated, and may be continuing to operate, to shape the policy agenda and thus prevent solutions to the insurance problems of self-employed midwives being found
BHPR research: qualitative1.âComplex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis
Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 â, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duckâ). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?â). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has goneâ). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining aboutâ). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes
Risk factors associated with short-term complications in mandibular fractures: the MANTRA studyâa Maxillofacial Trainee Research Collaborative (MTReC)
Abstract
Introduction
Complications following mandibular fractures occur in 9â23% of patients. Identifying those at risk is key to prevention. Previous studies highlighted smoking, age and time from injury to presentation as risk factors but rarely recorded other possible confounders. In this paper, we use a collaborative snapshot audit to document novel risk factors and confirm established risks for complications following the treatment of mandibular fractures.
Methods
The audit was carried out by 122 OMFS trainees across the UK and Ireland (49 centres) over 6Â months, coordinated by the Maxillofacial Surgery Trainees Research Collaborative. Variables recorded included basic demography, medical and social history, injury mechanism and type, management and 30-day outcome.
Results
Nine hundred and forty-seven (947) patients with fractured mandibles were recorded. Surgical management was carried out in 76.3%. Complications at 30Â days occurred 65 (9%) of those who were managed surgically. Risk factors for complications included male sex, increasing age, any medical history, increasing number of cigarettes smoked per week, increasing alcohol use per week, worse oral hygiene and increased time from injury to presentation.
Discussion
We have used a large prospective snapshot audit to confirm established risk factors and identify novel risk factors. We demonstrate that time from injury to presentation is confounded by other indicators of poor health behaviour. These results are important in designing trial protocols for management of mandibular fractures and in targeting health interventions to patients at highest risk of complications.
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