468 research outputs found

    Discrepancy-based error estimates for Quasi-Monte Carlo. I: General formalism

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    We show how information on the uniformity properties of a point set employed in numerical multidimensional integration can be used to improve the error estimate over the usual Monte Carlo one. We introduce a new measure of (non-)uniformity for point sets, and derive explicit expressions for the various entities that enter in such an improved error estimate. The use of Feynman diagrams provides a transparent and straightforward way to compute this improved error estimate.Comment: 23 pages, uses axodraw.sty, available at ftp://nikhefh.nikhef.nl/pub/form/axodraw Fixed some typos, tidied up section 3.

    Effectiveness of a structured, framework-based approach to implementation: the Researching Effective Approaches to Cleaning in Hospitals (REACH) Trial.

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    BACKGROUND:Implementing sustainable practice change in hospital cleaning has proven to be an ongoing challenge in reducing healthcare associated infections. The purpose of this study was to develop a reliable framework-based approach to implement and quantitatively evaluate the implementation of evidence-based practice change in hospital cleaning. DESIGN/METHODS:The Researching Effective Approaches to Cleaning in Hospitals (REACH) trial was a pragmatic, stepped-wedge randomised trial of an environmental cleaning bundle implemented in 11 Australian hospitals from 2016 to 2017. Using a structured multi-step approach, we adapted the integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) framework to support rigorous and tailored implementation of the cleaning bundle intervention in eleven diverse and complex settings. To evaluate the effectiveness of this strategy we examined post-intervention cleaning bundle alignment calculated as a score (an implementation measure) and cleaning performance audit data collected using ultraviolet (UV) gel markers (an outcome measure). RESULTS:We successfully implemented the bundle and observed improvements in cleaning practice and performance, regardless of hospital size, intervention duration and contextual issues such as staff and organisational readiness at baseline. There was a positive association between bundle alignment scores and cleaning performance at baseline. This diminished over the duration of the intervention, as hospitals with lower baseline scores were able to implement practice change successfully. CONCLUSION:Using a structured framework-based approach allows for pragmatic and successful implementation of clinical trials across diverse settings, and assists with quantitative evaluation of practice change. TRIAL REGISTRATION:Australia New Zealand Clinical Trial Registry ACTRN12615000325505, registered on 4 September 2015

    Evaluation of a chest radiograph reading and recording system for tuberculosis in a HIV-positive cohort.

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    Aim To assess the impact of introducing a chest radiograph reading and recording system (CRRS) with a short training session, on the accuracy and inter-reader variability of tuberculosis (TB) interpretation of chest radiographs (CXRs) by a group of non-expert readers in a human immunodeficiency virus (HIV)-positive cohort. Materials and methods A set of 139 CXRs was reviewed by a group of eight physicians pre- and post-intervention at two clinics in Shan State, Myanmar, providing HIV/TB diagnosis and treatment services. The results were compared against the consensus of expert radiologists for accuracy. Results Overall accuracy was similar pre- and post-intervention for most physicians with an average area under the receiver operating characteristic curve difference of 0.02 (95% confidence interval: –0.03, 0.07). The overall agreement among physicians was poor pre- and post-intervention (Fleiss Îș=0.35 and Îș=0.29 respectively). The assessment of agreement for specific disease patterns associated with active TB in HIV-infected patients showed that for intrinsically subtle findings, the agreement was generally poor but better for the more intrinsically obvious disease patterns: pleural effusion (Cohen’s kappa range = 0.37–0.67) and milliary nodular pattern (Cohen’s kappa range = 0.25–0.52). Conclusion This study demonstrated limited impact of the introduction of a CRRS on CXR accuracy and agreement amongst non-expert readers. The role in which CXRs are used for TB diagnosis in a HIV-positive cohort in similar clinical contexts should be reviewed

    Sociology’s missed opportunity: John Stuart-Glennie’s lost theory of the moral revolution, also known as the axial age

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    In 1873, 75 years before Karl Jaspers published his theory of the Axial Age in 1949, unknown to Jaspers and to contemporary scholars today, Scottish folklorist John Stuart Stuart-Glennie elaborated the first fully developed and nuanced theory of what he termed “the Moral Revolution” to characterize the historical shift emerging roughly around 600 BCE in a variety of civilizations, most notably ancient China, India, Judaism, and Greece, as part of a broader critical philosophy of history. He continued to write on the idea over decades in books and articles and also presented his ideas to the fledgling Sociological Society of London in 1905, which were published the following year in the volume Sociological Papers, Volume 2. This article discusses Stuart-Glennie’s ideas on the moral revolution in the context of his philosophy of history, including what he termed “panzooinism”; ideas with implications for contemporary debates in theory, comparative history, and sociology of religion. It shows why he should be acknowledged as the originator of the theory now known as the axial age, and also now be included as a significant sociologist in the movement toward the establishment of sociology

    A cluster-randomised controlled trial comparing school and community-based deworming for soil transmitted helminth control in school-age children: the CoDe-STH trial protocol

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    Background Current guidelines and targets for soil-transmitted helminth (STH) control focus on school-based deworming for school-age children, given the high risk of associated morbidity in this age group. However, expanding deworming to all age groups may achieve improved STH control among both the community in general and school-age children, by reducing their risk of reinfection. This trial aims to compare school-based targeted deworming with community-wide mass deworming in terms of impact on STH infections among school-age children. Methods The CoDe-STH (Community Deworming against STH) trial is a cluster-randomised controlled trial (RCT) in 64 primary schools in Dak Lak province, Vietnam. The control arm will receive one round of school-based targeted deworming with albendazole, while in the intervention arm, community-wide mass deworming with albendazole will be implemented alongside school-based deworming. Prevalence of STH infections will be measured in school-age children at baseline and 12 months following deworming. The primary outcome is hookworm prevalence in school-age children at 12 months, by quantitative PCR. Analysis will be intention-to-treat, with outcomes compared between study arms using generalised linear and non-linear mixed models. Additionally, cost-effectiveness of mass and targeted deworming will be calculated and compared, and focus group discussions and interviews will be used to assess acceptability and feasibility of deworming approaches. Individual based stochastic models will be used to predict the impact of mass and targeted deworming strategies beyond the RCT timeframe to assess the likelihood of parasite population ‘bounce-back’ if deworming is ceased due to low STH prevalence. Discussion The first large-scale trial comparing mass and targeted deworming for STH control in South East Asia will provide key information for policy makers regarding the optimal design of STH control programs

    Site adaptations of Acanthogyrus (Acanthosentis) tilapiae: Observations through light and scanning electron microscopy

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    Acanthogyrus (Acanthosentis) tilapiae parasites were collected from the intestines of 300 fish belonging to three tilapia species sourced at the River Nile, Giza, Egypt. The proboscis of the parasite was characterized by three rows of hooks that curved towards the posterior of the body. The first row is supported by unmodified hooks. The parasite tegument has a series of alternative folds and a large number of pores. Sensory ganglia are located on the surface of the proboscis and body. Acanthogyrus (Acanthosentis) tilapiae provokes an aggressive host response indicated by hyperplasia of the intestinal goblet cells and focal eosinophil infiltrations. This acanthocephalan parasite shows a highly modified adaptation to its site of host infection

    Variation in hospital cleaning practice and process in Australian hospitals: A structured mapping exercise

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    Background The purpose of this paper is to highlight the range of cleaning practices and processes in 11 Australian hospitals and to discuss the challenges this variation poses to the implementation of clinical trials or changes to hospital cleaning practices. Methods A cross-sectional study design was used to determine cleaning practices and processes in hospitals participating in the ‘Researching Effective Approaches to Cleaning in Hospitals’ (REACH) study. A standardised template and approach was used to collect information. Data collection activities included structured on-site discussions, a review of hospital practices and a document review of policy and procedural documents related to cleaning. Results Variations in the auditing process used to evaluate environmental cleanliness, cleaning practices, product use, training and communication pathways available to cleaning staff were identified. There was also variation in workforce structure and responsibilities for cleaning. Conclusion This paper is the first to describe the differences in cleaning practices between Australian hospitals. The variations identified present a number of challenges for the conduct of research and have important implications for both monitoring of and standards for cleanliness. These challenges include implementing a practice change or cleaning study where hospitals have different processes, practices and structures

    Zinterhof Sequences in GRID-Based Numerical Integration

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    The appropriateness of Zinterhof sequences to be used in GRID-based QMC integration is discussed. Theoretical considerations as well as experimental investigations are conducted comparing and assessing different strategies for an efficient and reliable usage. The high robustness and ease of construction exhibited by those sequences qualifies them as excellent QMC point set candidates for heterogeneous environments like the GRID

    Soil-transmitted helminth infections and nutritional indices among Filipino schoolchildren

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    BACKGROUND: Soil-transmitted helminth (STH) infections are still prevalent among schoolchildren in the Philippines. We evaluated the risk factors associated with STH and the relationship between STH and nutritional indices among schoolchildren aged 9-10 years in Laguna province, the Philippines. METHODS: We used the baseline data from 40 schools enrolled in a randomised controlled trial of the Magic Glasses Philippines health education package. Data on demographic and socio-economic variables, and STH related knowledge, attitudes and practices, were obtained through a questionnaire. Stool samples were collected and assessed for STH egg presence using the Kato-Katz technique. Haemoglobin levels and height and weight of study participants were also determined. The generalized estimating equations approach was used to construct logistic regression models to assess STH-associated risk factors, and the association between any STH infection and anaemia, child stunting, wasting and being underweight. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000508471). FINDINGS: Among 1,689 schoolchildren, the prevalence of any STH was 23%. The prevalence of anaemia, stunting, being underweight and wasting was 13%, 20.2%, 19% and 9.5%, respectively. Age, socio-economic status, rural/urban classification of schools and knowledge of STH were significant risk factors for acquiring a STH infection. Moreover, infections with any STH were significantly associated with stunting (P = <0.001) and being underweight (P = <0.003), but not wasting (P = 0.375) or anaemia (P = 0.462) after controlling for confounding covariates. CONCLUSION: The study findings emphasise the need for sustainable deworming in tandem with other measures such as the provision of health education, improvements in sanitation and hygiene, and nutritional programs in order to control STH infections and improve morbidity outcomes in schoolchildren. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ACTRN12616000508471)
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