143 research outputs found
Creative Activism – learning everywhere with children and young people
Creative activism is an approach to education that asks, ‘What can happen when we take learning outside the classroom and think of it happening everywhere?’. Two charities - House of Imagination and Cambridge Curiosity and Imagination - have been asking this question in their creative place-making programmes working with socially engaged artists and communities linked to primary schools in Bath and Cambridge. Young children and adults co-create and speculate about the future of their communities and environments in these different geographical locations. This article draws together our shared understanding of creative pedagogies and the value to everyone of working in this way
INTERSTICE. Training course for Education students
INTERSTICE is an Erasmus+ project developed by universities, artists and cultural settings from Catalonia, United Kingdom, Italy, and Norway to promote spaces of encounter between educators, artists, and children, to improve our learning processes and to build a pedagogy of co-creation through the arts. All University partners of INTERSTICE project designed and developed training experiences for prospective educators, with the active involvement of artists, cultural setting and schools. In this material, the four experiences and summarized, and some reflexions are offered in order to inspire more university professors
Calibration of Nebular Emission-line Diagnostics: II. Abundances
(Abridged) We examine standard methods of measuring nebular chemical
abundances, including estimates based on direct T_e measurements, and also
bright-line diagnostics. We use observations of 4 LMC HII regions whose
ionizing stars have classifications ranging from O7 to WN3. We assume a 2-zone
T_e structure to compute ionic abundances. We compare with photoionization
models tailored to the properties of the individual objects, and emphasize the
importance of correctly relating T_e in the two zones, which can otherwise
cause errors of ~0.2 dex in abundance estimates. There are no spatial
variations to within 0.1 - 0.15 dex in any of the objects, even one hosting 3
WR stars.
Our data agree with the modeled R23 and S23 diagnostics of O and S. We
present the first theoretical tracks for S23, which are in excellent agreement
with a larger dataset. However, contrary to earlier suggestions, S23 is much
more sensitive to the ionization parameter than is R23, because S23 does not
sample S IV. We therefore introduce S234 = ([SII]+[SIII]+[SIV])/H-beta.
Predicted and observed spatial variations in S234 are dramatically reduced in
contrast to S23. The intensity of [SIV]10.5 microns is easily estimated from a
simple relation between [SIV]/[SIII] and [OIII]/[OII]. This method of
estimating S234 yields excellent agreement with our models, hence we give a
theoretical calibration for S234. The double-valued structure of S23 and S234
remains an important problem as for R23, and presently we consider the S
diagnostics reliable only at Z < 0.5 Z_sol. However, the slightly larger
dynamic range and excellent compatibility with theoretical predictions suggest
the S diagnostics to be more effective abundance indicators than R23.Comment: Accepted to ApJ. 24 pages, 11 figures, uses emulateapj.st
Effect of Fouling on the Performance of an Instream Turbine
As the tidal energy industry starts to mature towards commercial projects a key focus is on reliable power performance. As for any marine application, fouling poses a potential performance reduction risk for instream turbine deployments.
SCHOTTEL HYDRO have developed their current commercial SCHOTTEL Instream Turbines. Four drivetrains with 6.3m rotors were deployed on the surface platform PLAT-I by Sustainable Marine Energy. One of PLAT-Is key features is access to the turbines for inspection and maintenance in situ. The system has undergone sea testing from 2017 to 2021 in Scotland and Nova Scotia (Canada).
This paper presents the hydrodynamic rotor performance reduction due to fouling based on full-scale experimental results. An in-house blade element momentum model is used to quantify the changes of the hydrodynamic forces in terms of lift and drag for the hydrofoils used. Furthermore, the effect of fouling on the downstream wake was quantified in the field. The performance reduction due to fouling is significant and leads to a power drop of up to 43%, whereas the thrust is reduced by 25%. This is also reflected in a reduction of the turbine’s downstream wake as a “fouled” rotor extracts less energy from the flow. Modifications of the polar data, used for semi-empirical performance predictions, are able to predict the effect of fouling on the rotor performance.
In general, the results derived from the testing prove the significance of access to the turbines in order to avoid reduction in the turbines’ performance due to fouling
Development and external validation of a clinical prediction model to aid coeliac disease diagnosis in primary care:an observational study
BACKGROUND: Coeliac disease (CD) affects approximately 1% of the population, although only a fraction of patients are diagnosed. Our objective was to develop diagnostic prediction models to help decide who should be offered testing for CD in primary care. METHODS: Logistic regression models were developed in Clinical Practice Research Datalink (CPRD) GOLD (between Sep 9, 1987 and Apr 4, 2021, n=107,075) and externally validated in CPRD Aurum (between Jan 1, 1995 and Jan 15, 2021, n=227,915), two UK primary care databases, using (and controlling for) 1:4 nested case-control designs. Candidate predictors included symptoms and chronic conditions identified in current guidelines and using a systematic review of the literature. We used elastic-net regression to further refine the models. FINDINGS: The prediction model included 24, 24, and 21 predictors for children, women, and men, respectively. For children, the strongest predictors were type 1 diabetes, Turner syndrome, IgA deficiency, or first-degree relatives with CD. For women and men, these were anaemia and first-degree relatives. In the development dataset, the models showed good discrimination with a c-statistic of 0·84 (95% CI 0·83–0·84) in children, 0·77 (0·77–0·78) in women, and 0·81 (0·81–0·82) in men. External validation discrimination was lower, potentially because ‘first-degree relative’ was not recorded in the dataset used for validation. Model calibration was poor, tending to overestimate CD risk in all three groups in both datasets. INTERPRETATION: These prediction models could help identify individuals with an increased risk of CD in relatively low prevalence populations such as primary care. Offering a serological test to these patients could increase case finding for CD. However, this involves offering tests to more people than is currently done. Further work is needed in prospective cohorts to refine and confirm the models and assess clinical and cost effectiveness. FUNDING: National Institute for Health Research Health Technology Assessment Programme (grant number NIHR129020
Mathematical Modelling of Mosquito Dispersal in a Heterogeneous Environment.
Mosquito dispersal is a key behavioural factor that affects the persistence and resurgence of several vector-borne diseases. Spatial heterogeneity of mosquito resources, such as hosts and breeding sites, affects mosquito dispersal behaviour and consequently affects mosquito population structures, human exposure to vectors, and the ability to control disease transmission. In this paper, we develop and simulate a discrete-space continuous-time mathematical model to investigate the impact of dispersal and heterogeneous distribution of resources on the distribution and dynamics of mosquito populations. We build an ordinary differential equation model of the mosquito life cycle and replicate it across a hexagonal grid (multi-patch system) that represents two-dimensional space. We use the model to estimate mosquito dispersal distances and to evaluate the effect of spatial repellents as a vector control strategy. We find evidence of association between heterogeneity, dispersal, spatial distribution of resources, and mosquito population dynamics. Random distribution of repellents reduces the distance moved by mosquitoes, offering a promising strategy for disease control
Accuracy of potential diagnostic indicators for coeliac disease:a systematic review protocol
INTRODUCTION: Coeliac disease (CD) is a systemic immune-mediated disorder triggered by gluten in genetically predisposed individuals. CD is diagnosed using a combination of serology tests and endoscopic biopsy of the small intestine. However, because of non-specific symptoms and heterogeneous clinical presentation, diagnosing CD is challenging. Early detection of CD through improved case-finding strategies can improve the response to a gluten-free diet, patients' quality of life and potentially reduce the risk of complications. However, there is a lack of consensus in which groups may benefit from active case-finding. METHODS AND ANALYSIS: We will perform a systematic review to determine the accuracy of diagnostic indicators (such as symptoms and risk factors) for CD in adults and children, and thus can help identify patients who should be offered CD testing. MEDLINE, Embase, Cochrane Library and Web of Science will be searched from 1997 until 2020. Screening will be performed in duplicate. Data extraction will be performed by one and checked by a second reviewer. Disagreements will be resolved through discussion or referral to a third reviewer. We will produce a narrative summary of identified prediction models. Studies, where 2×2 data can be extracted or reconstructed, will be treated as diagnostic accuracy studies, that is, the diagnostic indicators are the index tests and CD serology and/or biopsy is the reference standard. For each diagnostic indicator, we will perform a bivariate random-effects meta-analysis of the sensitivity and specificity. ETHICS AND DISSEMINATION: Results will be reported in peer-reviewed journals, academic and public presentations and social media. We will convene an implementation panel to advise on the optimum strategy for enhanced dissemination. We will discuss findings with Coeliac UK to help with dissemination to patients. Ethical approval is not applicable, as this is a systematic review and no research participants will be involved. PROSPERO REGISTRATION NUMBER: CRD42020170766
Defining the optimum strategy for identifying adults and children with coeliac disease: systematic review and economic modelling
BACKGROUND: Coeliac disease is an autoimmune disorder triggered by ingesting gluten. It affects approximately 1% of the UK population, but only one in three people is thought to have a diagnosis. Untreated coeliac disease may lead to malnutrition, anaemia, osteoporosis and lymphoma. OBJECTIVES: The objectives were to define at-risk groups and determine the cost-effectiveness of active case-finding strategies in primary care. DESIGN: (1) Systematic review of the accuracy of potential diagnostic indicators for coeliac disease. (2) Routine data analysis to develop prediction models for identification of people who may benefit from testing for coeliac disease. (3) Systematic review of the accuracy of diagnostic tests for coeliac disease. (4) Systematic review of the accuracy of genetic tests for coeliac disease (literature search conducted in April 2021). (5) Online survey to identify diagnostic thresholds for testing, starting treatment and referral for biopsy. (6) Economic modelling to identify the cost-effectiveness of different active case-finding strategies, informed by the findings from previous objectives. DATA SOURCES: For the first systematic review, the following databases were searched from 1997 to April 2021: MEDLINE® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), Cochrane Library, Web of Science™ (Clarivate™, Philadelphia, PA, USA), the World Health Organization International Clinical Trials Registry Platform ( WHO ICTRP ) and the National Institutes of Health Clinical Trials database. For the second systematic review, the following databases were searched from January 1990 to August 2020: MEDLINE, Embase, Cochrane Library, Web of Science, Kleijnen Systematic Reviews ( KSR ) Evidence, WHO ICTRP and the National Institutes of Health Clinical Trials database. For prediction model development, Clinical Practice Research Datalink GOLD, Clinical Practice Research Datalink Aurum and a subcohort of the Avon Longitudinal Study of Parents and Children were used; for estimates for the economic models, Clinical Practice Research Datalink Aurum was used. REVIEW METHODS: For review 1, cohort and case-control studies reporting on a diagnostic indicator in a population with and a population without coeliac disease were eligible. For review 2, diagnostic cohort studies including patients presenting with coeliac disease symptoms who were tested with serological tests for coeliac disease and underwent a duodenal biopsy as reference standard were eligible. In both reviews, risk of bias was assessed using the quality assessment of diagnostic accuracy studies 2 tool. Bivariate random-effects meta-analyses were fitted, in which binomial likelihoods for the numbers of true positives and true negatives were assumed. RESULTS: People with dermatitis herpetiformis, a family history of coeliac disease, migraine, anaemia, type 1 diabetes, osteoporosis or chronic liver disease are 1.5-2 times more likely than the general population to have coeliac disease; individual gastrointestinal symptoms were not useful for identifying coeliac disease. For children, women and men, prediction models included 24, 24 and 21 indicators of coeliac disease, respectively. The models showed good discrimination between patients with and patients without coeliac disease, but performed less well when externally validated. Serological tests were found to have good diagnostic accuracy for coeliac disease. Immunoglobulin A tissue transglutaminase had the highest sensitivity and endomysial antibody the highest specificity. There was little improvement when tests were used in combination. Survey respondents (n = 472) wanted to be 66% certain of the diagnosis from a blood test before starting a gluten-free diet if symptomatic, and 90% certain if asymptomatic. Cost-effectiveness analyses found that, among adults, and using serological testing alone, immunoglobulin A tissue transglutaminase was most cost-effective at a 1% pre-test probability (equivalent to population screening). Strategies using immunoglobulin A endomysial antibody plus human leucocyte antigen or human leucocyte antigen plus immunoglobulin A tissue transglutaminase with any pre-test probability had similar cost-effectiveness results, which were also similar to the cost-effectiveness results of immunoglobulin A tissue transglutaminase at a 1% pre-test probability. The most practical alternative for implementation within the NHS is likely to be a combination of human leucocyte antigen and immunoglobulin A tissue transglutaminase testing among those with a pre-test probability above 1.5%. Among children, the most cost-effective strategy was a 10% pre-test probability with human leucocyte antigen plus immunoglobulin A tissue transglutaminase, but there was uncertainty around the most cost-effective pre-test probability. There was substantial uncertainty in economic model results, which means that there would be great value in conducting further research. LIMITATIONS: The interpretation of meta-analyses was limited by the substantial heterogeneity between the included studies, and most included studies were judged to be at high risk of bias. The main limitations of the prediction models were that we were restricted to diagnostic indicators that were recorded by general practitioners and that, because coeliac disease is underdiagnosed, it is also under-reported in health-care data. The cost-effectiveness model is a simplification of coeliac disease and modelled an average cohort rather than individuals. Evidence was weak on the probability of routine coeliac disease diagnosis, the accuracy of serological and genetic tests and the utility of a gluten-free diet. CONCLUSIONS: Population screening with immunoglobulin A tissue transglutaminase (1% pre-test probability) and of immunoglobulin A endomysial antibody followed by human leucocyte antigen testing or human leucocyte antigen testing followed by immunoglobulin A tissue transglutaminase with any pre-test probability appear to have similar cost-effectiveness results. As decisions to implement population screening cannot be made based on our economic analysis alone, and given the practical challenges of identifying patients with higher pre-test probabilities, we recommend that human leucocyte antigen combined with immunoglobulin A tissue transglutaminase testing should be considered for adults with at least a 1.5% pre-test probability of coeliac disease, equivalent to having at least one predictor. A more targeted strategy of 10% pre-test probability is recommended for children (e.g. children with anaemia). FUTURE WORK: Future work should consider whether or not population-based screening for coeliac disease could meet the UK National Screening Committee criteria and whether or not it necessitates a long-term randomised controlled trial of screening strategies. Large prospective cohort studies in which all participants receive accurate tests for coeliac disease are needed. STUDY REGISTRATION: This study is registered as PROSPERO CRD42019115506 and CRD42020170766. FUNDING: This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 44. See the NIHR Journals Library website for further project information
Role of mass drug administration in elimination of Plasmodium falciparum malaria: a consensus modelling study
Background Mass drug administration for elimination of Plasmodium falciparum malaria is recommended by WHO
in some settings. We used consensus modelling to understand how to optimise the effects of mass drug administration
in areas with low malaria transmission.
Methods We collaborated with researchers doing field trials to establish a standard intervention scenario and
standard transmission setting, and we input these parameters into four previously published models. We then
varied the number of rounds of mass drug administration, coverage, duration, timing, importation of infection, and
pre-administration transmission levels. The outcome of interest was the percentage reduction in annual mean
prevalence of P falciparum parasite rate as measured by PCR in the third year after the final round of mass drug
administration.
Findings The models predicted differing magnitude of the effects of mass drug administration, but consensus
answers were reached for several factors. Mass drug administration was predicted to reduce transmission over a
longer timescale than accounted for by the prophylactic effect alone. Percentage reduction in transmission was
predicted to be higher and last longer at lower baseline transmission levels. Reduction in transmission resulting from
mass drug administration was predicted to be temporary, and in the absence of scale-up of other interventions, such
as vector control, transmission would return to pre-administration levels. The proportion of the population treated in
a year was a key determinant of simulated effectiveness, irrespective of whether people are treated through high
coverage in a single round or new individuals are reached by implementation of several rounds. Mass drug
administration was predicted to be more effective if continued over 2 years rather than 1 year, and if done at the time
of year when transmission is lowest.
Interpretation Mass drug administration has the potential to reduce transmission for a limited time, but is not an
effective replacement for existing vector control. Unless elimination is achieved, mass drug administration has to be
repeated regularly for sustained effect
Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study
OBJECTIVES: To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. POPULATION AND METHODS: We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the "index test"), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. RESULTS: 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. CONCLUSIONS: The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service laboratories should consider adopting procedures used in the research laboratory for paediatric urine samples. Primary care clinicians should try to obtain clean catch samples, even in very young children
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