UK Foot and Mouth disease: a systemic risk assessment of existing controls

This article details a systemic analysis of the controls in place and possible interventions available to further reduce the risk of a foot and mouth disease (FMD) outbreak in the United Kingdom. Using a research-based network analysis tool, we identify vulnerabilities within the multibarrier control system and their corresponding critical control points (CCPs). CCPs represent opportunities for active intervention that produce the greatest improvement to United Kingdom's resilience to future FMD outbreaks. Using an adapted ‘features, events, and processes’ (FEPs) methodology and network analysis, our results suggest that movements of animals and goods associated with legal activities significantly influence the system's behavior due to their higher frequency and ability to combine and create scenarios of exposure similar in origin to the U.K. FMD outbreaks of 1967/8 and 2001. The systemic risk assessment highlights areas outside of disease control that are relevant to disease spread. Further, it proves to be a powerful tool for demonstrating the need for implementing disease controls that have not previously been part of the system

Scientific commentary: Strategic analysis of environmental policy risks-heat maps, risk futures and the character of environmental harm

We summarise our recent efforts on the policy level risk appraisal of environmental risks. These have necessitated working closely with policy teams and a requirement to maintain crisp and accessible messages for policy audiences. Our comparative analysis uses heat maps, supplemented with risk narratives, and employs the multidimensional character of risks to inform debates on the management of current residual risk and future threats. The policy research and ensuing analysis raises core issues about how comparative risk analyses are used by policy audiences, their validation and future developments that are discussed in the commentary below

Modelling Ice Sheets and Sea Level During the Penultimate Deglaciation and the Last Interglacial: Uncertainty, Sensitivity, and Calibration

Antarctica's contribution to future global mean sea level rise is likely to be significant, and yet the rate, magnitude, and timing of this contribution beyond 2300 is poorly understood as predicted future melt scenarios are outside the window of modern observations. The Last Interglacial period was the last time in Earth's history that the global mean sea level was higher than today, driven, in part, by a smaller than present-day Antarctic ice sheet and could, therefore, provide constraints on scenarios and mechanisms of future ice-sheet melt. The Last Interglacial evolution of Antarctic ice-sheet geometry resulted in a particular global pattern, or fingerprint, of Antarctic-driven sea-level change, subsequently recorded in records of Last Interglacial relative sea levels. Records from certain Eurasia regions may be sensitive to this fingerprint and could be used to help uncover Last Interglacial Antarctic ice-sheet evolution. However, for this analysis, the complex contribution of glacial isostatic adjustment to Eurasian Last Interglacial relative sea-level records must be quantified. This thesis explores uncertainty in the Penultimate Glacial Maximum and subsequent Penultimate Deglaciation of the Eurasian ice sheet, the predominant driver of Eurasian glacial isostatic adjustment during the Last Interglacial, using a simple, calibrated ice-sheet model, resulting in a Penultimate Glacial Maximum volume of 48 ± 8 m SLE. The sensitivity of Eurasian Last Interglacial relative sea level is quantified with respect to ice-sheet and Earth model uncertainty in which the latter is found to be dominant. A suite of Last Interglacial Antarctic ice-sheet scenarios are developed to determine regional sensitivity to Antarctic ice-sheet changes, revealing a particularly strong influence in Wales, Atlantic, and English Channel regions. Finally, Bayesian history matching is applied to compare a relative sea-level ensemble against a Last Interglacial sea-level database, suggesting an Antarctic ice-sheet melt contribution of 3.2 - 9.3 m (likely, 66th percentile). However, when compared against relative sea-level data, none of the modelled scenarios are found to be implausible. More work is needed to constrain the large model-data uncertainties before rates, timings and East vs West contributions of the Antarctic ice sheet during the Last Interglacial can be identified

A traffic light grading system of hip dysplasia to predict the success of arthroscopic hip surgery

Background: The role of hip arthroscopy in dysplasia is controversial. Purpose: Determine the 7-year joint preservation rate following hip arthroscopy in hip dysplasia and identify anatomical and intra-operative features that predict success of hip preservation with arthroscopic surgery allowing formulation of an evidence-based classification. Study Design: Cohort Study; Level of evidence: 3 Methods: Between 2008 and 2013, 111 hips with dysplastic features [acetabular index (AI) > 10° and/or centre-edge angle (CEA) <25°] having undergone an arthroscopy were identified. Clinical, radiological and operative findings and type of procedure performed were reviewed. Radiographic evaluations of the operated hip [acetabular index (AI), centre-edge angle (CEA), extrusion index] were performed. Outcome measures included whether the hip was preserved at follow-up, pre- and post-operative NAHS and HOOS scores. We calculated AI and CEA factored (AIf and CEAf respectively) by a measure of articular wear as follows: AIf = AI x (number of UCL wear zones +1) CEAf = CEA / (number of UCL zones + 1) A contour plot of the resulting probability value of failure for every combination of AIf and CEAf allowed for the determination of the zones with the lowest and highest incidence of failure to preserve the hip respectively. Results: The mean AI and CEA were 7.8° and 18.0°, respectively. At a mean follow-up of 4.4 years, 33 hips had failed requiring a hip arthroplasty. The 7- year joint survival was 68%. The mean improvement in NAHS and HOOS were 7.8 and 23 points respectively. The zone with the greatest chance of joint preservation (odds ratio: 10, p<0.001) was AIf: 0 – 15 and CEAf: 15 – 25 (Green Zone); on the contrary the zone with the greatest chance of failure (odds ratio: 10, p<0.001) was AIf: 20 – 100 and CEAf : 0 – 10 (Red Zone). Conclusion: Overall, the 7- year hip survival in hip dysplasia appears inferior compared to reports of Femoro-Acetabular Impingement cases. Hip arthroscopy is associated with excellent chance of hip preservation in mild (Green Zone) dysplasia (AI< 15° & CEA: 15 – 25°) and no (or little) articular wear. Hip arthroscopy should not be performed in cases with severe (Red Zone) dysplasia (AI> 20° & CEA< 10°)

Thrust Stand Characterization of the NASA Evolutionary Xenon Thruster (NEXT)

Direct thrust measurements have been made on the NASA Evolutionary Xenon Thruster (NEXT) ion engine using a standard pendulum style thrust stand constructed specifically for this application. Values have been obtained for the full 40-level throttle table, as well as for a few off-nominal operating conditions. Measurements differ from the nominal NASA throttle table 10 (TT10) values by 3.1 percent at most, while at 30 throttle levels (TLs) the difference is less than 2.0 percent. When measurements are compared to TT10 values that have been corrected using ion beam current density and charge state data obtained at The Aerospace Corporation, they differ by 1.2 percent at most, and by 1.0 percent or less at 37 TLs. Thrust correction factors calculated from direct thrust measurements and from The Aerospace Corporation s plume data agree to within measurement error for all but one TL. Thrust due to cold flow and "discharge only" operation has been measured, and analytical expressions are presented which accurately predict thrust based on thermal thrust generation mechanisms

Integrating horizon scanning and strategic risk prioritisation using a weight of evidence framework to inform policy decisions

Poor connection between data on emerging issues and credible policy decisions continues to challenge governments, and is only likely to grow as demands on time and resources increase. Here we summarise recent efforts to integrate horizon scanning and risk prioritisation approaches to better connect emerging issues to the political discourse on environmental and food-related issues. Our categorisation of insights including potential future risks and opportunities to inform policy discussions has emerged from a structured three-year programme of horizon scanning for a UK pan-governmental futures partnership led by the Department for Environment, Food and Rural Affairs (Defra). Our efforts to integrate horizon scanning and risk prioritisation, utilising a qualitative weight of evidence framework, has created a systematic process for identifying all signals of potential future change with significant impact for the strategic mission and underlying values of policy actors. Our approach encourages an exploration of factors out of the control of organisations, recognising that resilience depends on the flexibility of management strategies and the preparedness to deal with a variety of unexpected outcomes. We discuss how this approach addresses key cultural and evaluative challenges that policy actors have had in embedding horizon scanning in evidence-based policy processes, and suggest further developments to build confidence in the use of horizon scanning for strategic planning

Spatially-Resolved Beam Current and Charge-State Distributions for the NEXT Ion Engine

Plume characterization tests with the 36-cm NEXT ion engine are being performed at The Aerospace Corporation using engineering-model and prototype-model thrusters. We have examined the beam current density and xenon charge-state distribution as functions of position on the accel grid. To measure the current density ratio j++/j+, a collimated Eprobe was rotated through the plume with the probe oriented normal to the accel electrode surface at a distance of 82 cm. The beam current density jb versus radial position was measured with a miniature planar probe at 3 cm from the accel. Combining the j++/j+ and jb data yielded the ratio of total Xe+2 current to total Xe+1 current (J++/J+) at forty operating points in the standard throttle table. The production of Xe+2 and Xe+3 was measured as a function of propellant utilization to support performance and lifetime predictions for an extended throttle table. The angular dependence of jb was measured at intermediate and far-field distances to assist with plume modeling and to evaluate the thrust loss due to beam divergence. Thrust correction factors were derived from the total doubles-to-singles current ratio and from the far-field divergence dat

Low back pain in junior Australian Rules football: a cross-sectional survey of elite juniors, non-elite juniors and non-football playing controls

<p>Abstract</p> <p>Background</p> <p>Low back pain in junior Australian Rules footballers has not been investigated despite findings that back pain is more prevalent, severe and frequent in senior footballers than non-athletic controls and findings that adolescent back pain is a strong predictor for adult back pain. The aim of this study was to determine the prevalence, intensity, quality and frequency of low back pain in junior Australian Rules footballers and a control group and to compare this data between groups.</p> <p>Methods</p> <p>A cross-sectional survey of male non-elite junior (n = 60) and elite junior players (n = 102) was conducted along with a convenience sample of non-footballers (school children) (n = 100). Subjects completed a self-reported questionnaire on low back pain incorporating the Quadruple Visual Analogue Scale and McGill Pain Questionnaire (short form), along with additional questions adapted from an Australian epidemiological study. Linear Mixed Model (Residual Maximum Likelihood) methods were used to compare differences between groups. Log-linear models were used in the analysis of contingency tables.</p> <p>Results</p> <p>For current, average and best low back pain levels, elite junior players had higher pain levels (p < 0.001), with no difference noted between non-elite juniors and controls for average and best low back pain. For low back pain at worst, there were significant differences in the mean pain scores. The difference between elite juniors and non-elite juniors (p = 0.040) and between elite juniors and controls (p < 0.001) was significant, but not between non-elite juniors and controls. The chance of suffering low back pain increases from 45% for controls, through 55% for non-elite juniors to 66.7% for elite juniors. The chance that a pain sufferer experiences chronic pain is 16% for controls and 41% for non-elite junior and elite junior players. Elite junior players experienced low back pain more frequently (p = 0.002), with no difference in frequency noted between non-elite juniors and controls. Over 25% of elite junior and non-elite junior players reported that back pain impacted their performance some of the time or greater.</p> <p>Conclusions</p> <p>This study demonstrated that when compared with non-elite junior players and non-footballers of a similar age, elite junior players experience back pain more severely and frequently and have higher prevalence and chronicity rates.</p