4,035 research outputs found

    Seasonal variations in incidence and maternal-fetal outcomes of gestational diabetes.

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    AIMS: To determine whether the neonatal and delivery outcomes of gestational diabetes vary seasonally in the context of a relatively cool temperate climate. METHODS: A retrospect cohort of 23 735 women consecutively delivering singleton, live-born term infants in a single tertiary obstetrics centre in the UK (2004-2008) was identified. A total of 985 (4.1%) met the diagnostic criteria for gestational diabetes. Additive dynamic regression models, adjusted for maternal age, BMI, parity and ethnicity, were used to compare gestational diabetes incidence and outcomes over annual cycles. Outcomes included: random plasma glucose at booking; gestational diabetes diagnosis; birth weight centile; and delivery mode. RESULTS: The incidence of gestational diabetes varied by 30% from peak incidence (October births) to lowest incidence (March births; P=0.031). Ambient temperature at time of testing (28 weeks) was strongly positively associated with diagnosis (P<0.001). Significant seasonal variation was evident in birth weight in gestational diabetes-affected pregnancies (average 54th centile June to September; average 60th centile December to March; P=0.027). Emergency Caesarean rates also showed significant seasonal variation of up to 50% (P=0.038), which was closely temporally correlated with increased birth weights. CONCLUSIONS: There is substantial seasonal variation in gestational diabetes incidence and maternal-fetal outcomes, even in a relatively cool temperate climate. The highest average birth weight and greatest risk of emergency Caesarean delivery occurs in women delivering during the spring months. Recognizing seasonal variation in neonatal and delivery outcomes provides new opportunity for individualizing approaches to managing gestational diabetes.Catherine Aiken is supported by an Isaac Newton Trust/Wellcome Trust ISSF/ University of Cambridge Joint Research Grant. Claire Meek receives salary funding from the Diabetes UK Harry Keen Intermediate Clinical Fellowship (17/0005712). The funders have had no role in study design, data collection, data analysis, manuscript preparation and/or publication decisions

    The underestimated biodiversity of tropical grassy biomes

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    For decades, there has been enormous scientific interest in tropical savannahs and grasslands, fuelled by the recognition that they are a dynamic and potentially unstable biome, requiring periodic disturbance for their maintenance. However, that scientific interest has not translated into widespread appreciation of, and concern about threats to, their biodiversity. In terms of biodiversity, grassy biomes are considered poor cousins of the other dominant biome of the tropics—forests. Simple notions of grassy biomes being species-poor cannot be supported; for some key taxa, such as vascular plants, this may be valid, but for others it is not. Here, we use an analysis of existing data to demonstrate that high-rainfall tropical grassy biomes (TGBs) have vertebrate species richness comparable with that of forests, despite having lower plant diversity. The Neotropics stand out in terms of both overall vertebrate species richness and number of range-restricted vertebrate species in TGBs. Given high rates of land-cover conversion in Neotropical grassy biomes, they should be a high priority for conservation and greater inclusion in protected areas. Fire needs to be actively maintained in these systems, and in many cases re-introduced after decades of inappropriate fire exclusion. The relative intactness of TGBs in Africa and Australia make them the least vulnerable to biodiversity loss in the immediate future. We argue that, like forests, TGBs should be recognized as a critical—but increasingly threatened—store of global biodiversity

    Model-measurement consistency and limits of bioaerosol abundance over the continental United States

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    Due to low concentrations and chemical complexity, in situ observations of bioaerosol are geographically and temporally sparse, and this limits the accuracy of current emissions inventories. In this study, we apply a new methodology, including corrections for misidentification of mineral dust, to measurements of single particles over four airborne sampling campaigns to derive vertical profiles of bioaerosol over the continental United States. The new methodology is based on single-particle mass spectrometry (SPMS); it can extend historic datasets to include measurements of bioaerosol, it allows comparisons to other techniques, and it generally agrees with a global aerosol model. In the locations sampled, bioaerosols were at least a factor of 10 less abundant than mineral dust. Below 2 km, bioaerosol concentrations were measured between 6×103 and 2×104 m−3. Between 2 and 8 km, bioaerosol concentrations were between 0 and 2×104 m−3, and above 8 km, bioaerosol concentrations were between 0 and 1×103 m−3. Between 30 % and 80 % of single bioaerosol particles detected were internally mixed with dust. A direct comparison of the SPMS methodology with a co-located wideband integrated bioaerosol sensor (WIB) fluorescence sensor on a mountaintop site showed agreement to within a factor of 3 over the common size range

    Learning from errors:Assessing final year medical students' reflection on safety improvement, five year cohort study

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    Abstract Background Investigation of real incidents has been consistently identified by expert reviews and student surveys as a potentially valuable teaching resource for medical students. The aim of this study was to adapt a published method to measure resident doctors’ reflection on quality improvement and evaluate this as an assessment tool for medical students. Methods The design is a cohort study. Medical students were prepared with a tutorial in team based learning format and an online Managing Incident Review course. The reliability of the modified Mayo Evaluation of Reflection on Improvement tool (mMERIT) was analysed with Generalizability G-theory. Long term sustainability of assessment of incident review with mMERIT was tested over five consecutive years. Results A total of 824 students have completed an incident review using 167 incidents from NHS Tayside’s online reporting system. In order to address the academic practice gap students were supervised by Senior Charge Nurses or Consultants on the wards where the incidents had been reported. Inter-rater reliability was considered sufficiently high to have one assessor for each student report. There was no evidence of a gradient in student marks across the academic year. Marks were significantly higher for students who used Section Questions to structure their reports compared with those who did not. In Year 1 of the study 21 (14%) of 153 mMERIT reports were graded as concern. All 21 of these students achieved the required standard on resubmission. Rates of resubmission were lower (3% to 7%) in subsequent years. Conclusions We have shown that mMERIT has high reliability with one rater. mMERIT can be used by students as part of a suite of feedback to help supplement their self-assessment on their learning needs and develop insightful practice to drive their development of quality, safety and person centred professional practice. Incident review addresses the need for workplace based learning and use of real life examples of mistakes, which has been identified by previous studies of education about patient safety in medical schools

    Fidelity of delivery and contextual factors influencing children’s level of engagement: Process evaluation of the Online Remote Behavioural Intervention for Tics (ORBIT) Trial (Preprint)

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    BACKGROUND: The Online Remote Behavioural Intervention for Tics (ORBIT) study was a multicentre randomized controlled trial of a complex intervention that consisted of an online behavioural intervention for children and young people (CYP) with tic disorders. In this first part of a two-stage process evaluation, we conducted a mixed-methods study exploring reach, dose, and fidelity of the intervention and contextual factors influencing engagement with the intervention. OBJECTIVE: This study aims to explore the fidelity of delivery and the contextual factors underpinning the ORBIT intervention. METHODS: Baseline study data and intervention usage metrics from participants in the intervention arm were used as quantitative implementation data (n=112). The experiences of being in the intervention were explored by semi-structured interviews with children (n=20) and parent (n=20) participants, therapists (n=4), and referring clinicians (n=6). A principal components analysis was used to create a comprehensive, composite measure of CYP’s engagement with the intervention. Engagement factor scores reflected relative uptake as assessed by a range of usage indices including chapters accessed, number of pages visited and number of logins. RESULTS: The intervention was implemented with high fidelity, and participants deemed the intervention acceptable and satisfactory. Engagement and adherence were high with child participants completing an average of 7.5/10 chapters and 100/112 (89.3%) participants completed a minimum of 4 chapters: the pre-defined threshold for effective dose. Compared to the total population of children with tic disorders, the sample tended to have more educated parents and live in more economically advantaged areas but socioeconomic factors were not related to engagement factor scores. Factors associated with higher engagement factor scores included participants enrolled at the London site vs. the Nottingham site (P=.011), self-referred vs. clinic-referred (P=.041), higher parental engagement as evidenced by number of parental chapters completed (ρ=0.73, n=111, P<.001) and more therapist time for parent (ρ=0.46, n=111, P<.001). A multiple linear regression indicated that parents’ chapter completion (β=.69, t110=10.18, P<.001) and therapist time for parent (β=.19, t110=2.95, P=.004) were the only significant independent predictors of engagement factor scores. CONCLUSIONS: Overall, the intervention had high fidelity of delivery and was evaluated positively by participants, although reach may have been constrained by the nature of the randomized controlled trial. Parental engagement and therapist time for parent were strong predictors of intervention implementation which has important implications for the design and implementation of digital therapeutic interventions into Child and Adolescent Mental Health Services. Clinical Trial: International Standard Randomized Controlled Trial Number (ISRCTN) 70758207; https://doi.org/10.1186/ISRCTN70758207 and ClinicalTrials.gov NCT03483493; https://clinicaltrials.gov/ct2/show/NCT0348349

    Factors influencing the efficacy of an online behavioural intervention for children and young people with tics: Process evaluation of a randomised controlled trial

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    The Online Remote Behavioural Intervention for Tics (ORBIT) trial found that an internet-delivered, therapist-supported, and parent-assisted Exposure and Response Prevention (ERP) intervention reduced tic severity and improved clinical outcomes. This process evaluation aimed to explore mechanisms of impact and factors influencing efficacy. Participants were 112 children with a tic disorder and their parents randomised to the active intervention arm of the ORBIT trial. Child engagement was assessed by usage metrics and parent engagement by chapter completion. Experiences of the digital intervention were explored by semi-structured interviews. Outcomes (3-months post randomisation) were change in tic severity and overall clinical improvement. Tic severity reduced from baseline to 3-month follow-up and 36% were rated as much improved clinically. Greater tic severity at baseline predicted reduction in tic severity. Parental engagement was the only independent predictor of clinical improvement. There were no statistically significant mediators or moderators of the relationship between level of child engagement and outcome. From the qualitative findings, child participants appreciated working together with parents on the intervention and participants found the intervention engaging. ORBIT may be an effective and acceptable intervention for children and young people with tic disorders, with parental engagement being a key factor in successful outcomes

    A review of the methodological features of systematic reviews in maternal medicine

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    Background In maternal medicine, research evidence is scattered making it difficult to access information for clinical decision making. Systematic reviews of good methodological quality are essential to provide valid inferences and to produce usable evidence summaries to guide management. This review assesses the methodological features of existing systematic reviews in maternal medicine, comparing Cochrane and non-Cochrane reviews in maternal medicine. Methods Medline, Embase, Database of Reviews of Effectiveness (DARE) and Cochrane Database of Systematic Reviews (CDSR) were searched for relevant reviews published between 2001 and 2006. We selected those reviews in which a minimum of two databases were searched and the primary outcome was related to the maternal condition. The selected reviews were assessed for information on framing of question, literature search and methods of review. Results Out of 2846 citations, 68 reviews were selected. Among these, 39 (57%) were Cochrane reviews. Most of the reviews (50/68, 74%) evaluated therapeutic interventions. Overall, 54/68 (79%) addressed a focussed question. Although 64/68 (94%) reviews had a detailed search description, only 17/68 (25%) searched without language restriction. 32/68 (47%) attempted to include unpublished data and 11/68 (16%) assessed for the risk of missing studies quantitatively. The reviews had deficiencies in the assessment of validity of studies and exploration for heterogeneity. When compared to Cochrane reviews, other reviews were significantly inferior in specifying questions (OR 20.3, 95% CI 1.1–381.3, p = 0.04), framing focussed questions (OR 30.9, 95% CI 3.7- 256.2, p = 0.001), use of unpublished data (OR 5.6, 95% CI 1.9–16.4, p = 0.002), assessment for heterogeneity (OR 38.1, 95%CI 2.1, 688.2, p = 0.01) and use of meta-analyses (OR 3.7, 95% CI 1.3–10.8, p = 0.02). Conclusion This study identifies areas which have a strong influence on maternal morbidity and mortality but lack good quality systematic reviews. Overall quality of the existing systematic reviews was variable. Cochrane reviews were of better quality as compared to other reviews. There is a need for good quality systematic reviews to inform practice in maternal medicine

    Decision for reconstructive interventions of the upper limb in individuals with tetraplegia: the effect of treatment characteristics

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    Objective: To determine the effect of treatment characteristics on the\ud decision for reconstructive interventions for the upper extremities (UE) in\ud subjects with tetraplegia. - \ud Setting: Seven specialized spinal cord injury centres in the Netherlands. - \ud Method: Treatment characteristics for UE reconstructive interventions were\ud determined. Conjoint analysis (CA) was used to determine the contribution\ud and the relative importance of the treatment characteristics on the decision\ud for therapy. Therefore, a number of different treatment scenarios using these\ud characteristics were established. Different pairs of scenarios were presented\ud to subjects who were asked to choose the preferred scenario of each set. - \ud Results: forty nine subjects with tetraplegia with a stable C5, C6 or C7\ud lesion were selected. All treatment characteristics significantly influenced\ud the choice for treatment. Relative importance of treatment characteristics\ud were: intervention type (surgery or surgery with FES implant) 13%, number\ud of operations 15%, in patient rehabilitation period 22%, ambulant\ud rehabilitation period 9%, complication rate 15%, improvement of elbow\ud function 10%, improvement of hand function 15%. In deciding for therapy\ud 40% of the subjects focused on one characteristic. - \ud Conclusion: CA is applicable in Spinal Cord Injury medicine to study the\ud effect of health outcomes and non-health outcomes on the decision for\ud treatment. Non-health outcomes which relate to the intensity of treatment\ud are equally important or even more important than functional outcome in the\ud decision for reconstructive UE surgery in subjects with tetraplegia

    An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students

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    &lt;p&gt;Aims: This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology.&lt;/p&gt; &lt;p&gt;Methods: Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C.&lt;/p&gt; &lt;p&gt;Results: A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not.&lt;/p&gt; &lt;p&gt;Conclusions: Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination.&lt;/p&gt

    Neutron cryo-crystallography captures the protonation state of ferryl heme in a peroxidase

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    Heme enzymes activate oxygen through formation of transient iron-oxo (ferryl) intermediates of the heme iron. A long-standing question has been the nature of the iron-oxygen bond and, in particular, the protonation state. We present neutron structures of the ferric derivative of cytochrome c peroxidase and its ferryl intermediate; these allow direct visualization of protonation states. We demonstrate that the ferryl heme is an Fe(IV)=O species and is not protonated. Comparison of the structures shows that the distal histidine becomes protonated on formation of the ferryl intermediate, which has implications for the understanding of O–O bond cleavage in heme enzymes. The structures highlight the advantages of neutron cryo-crystallography in probing reaction mechanisms and visualizing protonation states in enzyme intermediates
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