985 research outputs found
Novel inferences of ionisation & recombination for particle/power balance during detached discharges using deuterium Balmer line spectroscopy
The physics of divertor detachment is determined by divertor power, particle
and momentum balance. This work provides a novel analysis technique of the
Balmer line series to obtain a full particle/power balance measurement of the
divertor. This supplies new information to understand what controls the
divertor target ion flux during detachment.
Atomic deuterium excitation emission is separated from recombination
quantitatively using Balmer series line ratios. This enables analysing those
two components individually, providing ionisation/recombination source/sinks
and hydrogenic power loss measurements. Probabilistic Monte Carlo techniques
were employed to obtain full error propagation - eventually resulting in
probability density functions for each output variable. Both local and overall
particle and power balance in the divertor are then obtained. These techniques
and their assumptions have been verified by comparing the analysed synthetic
diagnostic 'measurements' obtained from SOLPS simulation results for the same
discharge. Power/particle balance measurements have been obtained during
attached and detached conditions on the TCV tokamak.Comment: The analysis results of this paper were formerly in arXiv:1810.0496
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Designing theoretically-informed implementation interventions
Clinical and health services research is continually producing new findings that may contribute to effective and efficient patient care. However, the transfer of research findings into practice is unpredictable and can be a slow and haphazard process. Ideally, the choice of implementation strategies would be based upon evidence from randomised controlled trials or systematic reviews of a given implementation strategy. Unfortunately, reviews of implementation strategies consistently report effectiveness some, but not all of the time; possible causes of this variation are seldom reported or measured by the investigators in the original studies. Thus, any attempts to extrapolate from study settings to the real world are hampered by a lack of understanding of the effects of key elements of individuals, interventions, and the settings in which they were trialled. The explicit use of theory offers a way of addressing these issues and has a number of advantages, such as providing: a generalisable framework within which to represent the dimensions that implementation studies address, a process by which to inform the development and delivery of interventions, a guide when evaluating, and a way to allow for an exploration of potential causal mechanisms. However, the use of theory in designing implementation interventions is methodologically challenging for a number of reasons, including choosing between theories and faithfully translating theoretical constructs into interventions. The explicit use of theory offers potential advantages in terms of facilitating a better understanding of the generalisability and replicability of implementation interventions. However, this is a relatively unexplored methodological area
High-quality chronic care delivery improves experiences of chronically ill patients receiving care
__Abstract__
Objective. Investigate whether high-quality chronic care delivery improved the experiences of patients.
Design. This study had a longitudinal design.
Setting and Participants. We surveyed professionals and patients in 17 disease management programs targeting patients with cardiovascular
diseases, chronic obstructive pulmonary disease, heart failure, stroke, comorbidity and eatin
Using psychological theory to understand the clinical management of type 2 diabetes in Primary Care : a comparison across two European countries
Peer reviewedPublisher PD
Estresse ocupacional e satisfação dos usuários com os cuidados de saúde primários em Portugal
The Portuguese primary healthcare sector has suffered changes due to a reform on the lines of the conceptual framework referred to by some authors as "New Public Management." These changes may be generating higher levels of occupational stress with a negative impact at individual and organizational levels. This study examines the experience of stress in 305 health professionals (physicians, nurses and clinical secretaries) and satisfaction with the services provided by them from 392 users. The population under scrutiny is taken from 10 type A and 10 type B Family Health Units (FHU). The results show that 84.2% of professionals report moderate to high levels of occupational stress with the nurses being those with higher levels. Users reported good levels of satisfaction, especially with the nursing services. There were no differences in stress level between type A and type B FHU, though there were at the level of user satisfaction of type B FHU users who show higher levels of satisfaction. It was seen that dimensions of user satisfaction were affected by stress related to excess work.info:eu-repo/semantics/publishedVersio
Systematic review of economic evaluations and cost analyses of guideline implementation strategies
Objectives To appraise the quality of economic studies undertaken as part of evaluations of guideline implementation strategies; determine their resources use; and recommend methods to improve future studies. Methods Systematic review of economic studies undertaken alongside robust study designs of clinical guideline implementation strategies published (1966-1998). Studies assessed against the BMJ economic evaluations guidelines for each stage of the guideline process (guideline development, implementation and treatment). Results 235 studies were identified, 63 reported some information on cost. Only 3 studies provided evidence that their guideline was effective and efficient. 38 reported the treatment costs only, 12 implementation and treatment costs, 11 implementation costs alone, and two guideline development, implementation and treatment costs. No study gave reasonably complete information on costs. Conclusions Very few satisfactory economic evaluations of guideline implementation strategies have been performed. Current evaluations have numerous methodological defects and rarely consider all relevant costs and benefits. Future evaluations should focus on evaluating the implementation of evidence based guidelines. Keywords: Cost-effectiveness analysis, physician (or health care professional) behaviour, practice guidelines, quality improvement, systematic review.Peer reviewedAuthor versio
Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.
OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age
Multi-Shooting Differential Dynamic Programming for Hybrid Systems using Analytical Derivatives
Differential Dynamic Programming (DDP) is a popular technique used to
generate motion for dynamic-legged robots in the recent past. However, in most
cases, only the first-order partial derivatives of the underlying dynamics are
used, resulting in the iLQR approach. Neglecting the second-order terms often
slows down the convergence rate compared to full DDP. Multi-Shooting is another
popular technique to improve robustness, especially if the dynamics are highly
non-linear. In this work, we consider Multi-Shooting DDP for trajectory
optimization of a bounding gait for a simplified quadruped model. As the main
contribution, we develop Second-Order analytical partial derivatives of the
rigid-body contact dynamics, extending our previous results for fixed/floating
base models with multi-DoF joints. Finally, we show the benefits of a novel
Quasi-Newton method for approximating second-order derivatives of the dynamics,
leading to order-of-magnitude speedups in the convergence compared to the full
DDP method.Comment: https://www.youtube.com/watch?v=C0h6mEpcnA
Update on World Health Organization HIV Drug Resistance Prevention and Assessment Strategy: 2004-2011
The HIV drug resistance (HIVDR) prevention and assessment strategy, developed by the World Health Organization (WHO) in partnership with HIVResNet, includes monitoring of HIVDR early warning indicators, surveys to assess acquired and transmitted HIVDR, and development of an accredited HIVDR genotyping laboratory network to support survey implementation in resource-limited settings. As of June 2011, 52 countries had implemented at least 1 element of the strategy, and 27 laboratories had been accredited. As access to antiretrovirals expands under the WHO/Joint United Nations Programme on HIV/AIDS Treatment 2.0 initiative, it is essential to strengthen HIVDR surveillance efforts in the face of increasing concern about HIVDR emergence and transmissio
Cluster randomised trial of a tailored intervention to improve the management of overweight and obesity in primary care in England
Background: Tailoring is a frequent component of approaches for implementing clinical practice guidelines, although evidence on how to maximise the effectiveness of tailoring is limited. In England, overweight and obesity are common, and national guidelines have been produced by the National Institute for Health and Care Excellence. However, the guidelines are not routinely followed in primary care. Methods: A tailored implementation intervention was developed following an analysis of the determinants of practice influencing the implementation of the guidelines on obesity and the selection of strategies to address the determinants. General practices in the East Midlands of England were invited to take part in a cluster randomised controlled trial of the intervention. The primary outcome measure was the proportion of overweight or obese patients offered a weight loss intervention. Secondary outcomes were the proportions of patients with (1) a BMI or waist circumference recorded, (2) record of lifestyle assessment, (3) referred to weight loss services, and (4) any change in weight during the study period. We also assessed the mean weight change over the study period. Follow-up was for 9 months after the intervention. A process evaluation was undertaken, involving interviews of samples of participating health professionals. Results: There were 16 general practices in the control group, and 12 in the intervention group. At follow-up, 15. 08 % in the control group and 13.19 % in the intervention group had been offered a weight loss intervention, odds ratio (OR) 1.16, 95 % confidence interval (CI) (0.72, 1.89). BMI/waist circumference measurement 42.71 % control, 39.56 % intervention, OR 1.15 (CI 0.89, 1.48), referral to weight loss services 5.10 % control, 3.67 % intervention, OR 1.45 (CI 0.81, 2.63), weight management in the practice 9.59 % control, 8.73 % intervention, OR 1.09 (CI 0.55, 2.15), lifestyle assessment 23.05 % control, 23.86 % intervention, OR 0.98 (CI 0.76, 1.26), weight loss of at least 1 kg 42.22 % control, 41.65 % intervention, OR 0.98 (CI 0.87, 1.09). Health professionals reported the interventions as increasing their confidence in managing obesity and providing them with practical resources. Conclusions: The tailored intervention did not improve the implementation of the guidelines on obesity, despite systematic approaches to the identification of the determinants of practice. The methods of tailoring require further development to ensure that interventions target those determinants that most influence implementation
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