The biomechanical characteristics of high-performance endurance running

The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study, therefore, sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 high-performance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6 m s−1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis used to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact

A marker set for measuring the kinematics of the lumbar spine and thoracic spine during running : a technical note

A protocol for tracking the motion of the lumbar spine, which uses seven skin mounted markers, has been adopted in previous studies investigating running. However, this configuration of can be difficult to track with passive motion capture systems. This study therefore investigated whether a four-marker configuration could accurately reproduce the pose of the lumbar spine obtained using the seven-marker configuration. The study also investigated two methods of tracking the thorax. The first method consisted of markers attached to the sterum and the second used two markers placed bilaterally over the acromioclavicular joints and another on the posterior thoracic spine. Kinematic data was collect for n=15 male subjects and the pose, calculated using the different tracking configurations, compared for both the lumbar spine and thoracic spine. The results demonstrated a good match between two lumbar tracking marker sets. However, there was considerable difference between the two thoracic markers sets which was likely due to movement of the arms influencing the pose of the thorax. We therefore recommend the use of four makers to track the motion of the lumbar spine and a rigid plate, mounted at the top of the sternum, to track motion of the thoracic spine during running

Reproducibility of kinematic measures of the thoracic spine, lumbar spine and pelvis during fast running

This study evaluated the reproducibility of the angular rotations of the thoracic spine, lumbar, spine, pelvis and lower extremity during running. In addition, the study compared kinematic, reproducibility between two methods for calculating kinematic trajectories: a six degrees of freedom, (6DOF) approach and a global optimisation (GO) approach. With the first approach segments were, treated independently, however with GO approach joint constraints were imposed to stop translation, of adjacent segments. A total of 12 athletes were tested on two separate days whilst running over, ground at a speed of 5.6ms-1. The results demonstrated good between-day reproducibility for most, kinematic parameters in the frontal and transverse planes with typical angular errors of 1.4-3°., Acceptable repeatability was also found in the sagittal plane. However, in this plane, although, kinematic waveform shape was preserved between testing session, there were sometimes shifts in, curve offset which lead to slightly higher angular errors, typically ranging from 1.9-3.5°. In general, the, results demonstrated similar levels of reproducibility for both computational approaches (6DOF and, GO) and therefore suggest that GO may not lead to improved kinematic reproducibility during running

Best practices for post-processing ensemble climate forecasts, part I: selecting appropriate recalibration methods

ArticleThis is the final version of the article. Available from the publisher via the DOI in this record.This study describes a systematic approach to selecting optimal statistical recalibration methods and hindcast designs for producing reliable probability forecasts on seasonal-to-decadal time scales. A new recalibration method is introduced that includes adjustments for both unconditional and conditional biases in the mean and variance of the forecast distribution, and linear time-dependent bias in the mean. The complexity of the recalibration can be systematically varied by restricting the parameters. Simple recalibration methods may outperform more complex ones given limited training data. A new cross-validation methodology is proposed that allows the comparison of multiple recalibration methods and varying training periods using limited data. Part I considers the effect on forecast skill of varying the recalibration complexity and training period length. The interaction between these factors is analysed for grid box forecasts of annual mean near-surface temperature from the CanCM4 model. Recalibration methods that include conditional adjustment of the ensemble mean outperform simple bias correction by issuing climatological forecasts where the model has limited skill. Trend-adjusted forecasts outperform forecasts without trend adjustment at almost 75% of grid boxes. The optimal training period is around 30 years for trend-adjusted forecasts, and around 15 years otherwise. The optimal training period is strongly related to the length of the optimal climatology. Longer training periods may increase overall performance, but at the expense of very poor forecasts where skill is limited

Potential impact of reactive vaccination in controlling cholera outbreaks: An exploratory analysis using a Zimbabwean experience

Background. To contain ongoing cholera outbreaks, the World Health Organization has suggested that reactive vaccination should be considered in addition to its previous control measures. Objectives. To explore the potential impact of a hypothetical reactive oral cholera vaccination using the example of the recent large-scale cholera outbreak in Zimbabwe. Methods. This was a retrospective cost-effectiveness analysis calculating the health and economic burden of the cholera outbreak in Zimbabwe with and without reactive vaccination. The primary outcome measure was incremental cost per disability-adjusted life year (DALY) averted. Results. Under the base-case assumptions (assuming 50% coverage among individuals aged ≥2 years), reactive vaccination could have averted 1 320 deaths and 23 650 DALYs. Considering herd immunity, the corresponding values would have been 2 920 deaths and 52 360 DALYs averted. The total vaccination costs would have been ~$74 million and ~$21 million, respectively, with per-dose vaccine price of US$5 and$1. The incremental costs per DALY averted of reactive vaccination were $2 770 and$370, respectively, for vaccine price set at $5 and$1. Assuming herd immunity, the corresponding cost was $980 with vaccine price of$5, and the programme was cost-saving with a vaccine price of $1. Results were most sensitive to case-fatality rate, per-dose vaccine price, and the size of the outbreak. Conclusions. Reactive vaccination has the potential to be a costeffective measure to contain cholera outbreaks in countries at high risk. However, the feasibility of implementation should be further evaluated, and caution is warranted in extrapolating the findings to different settings in the absence of other in-depth studies

A qualitative study of patients’ feedback about Outpatient Parenteral Antimicrobial Therapy (OPAT) services in Northern England: implications for service improvement

Objective Outpatient parenteral antimicrobial therapy (OPAT) provides opportunities for improved cost savings, but in the UK, implementation is patchy and a variety of service models are in use. The slow uptake in the UK and Europe is due to a number of clinical, financial and logistical issues, including concern about patient safety. The measurement of patient experience data is commonly used to inform commissioning decisions, but these focus on functional aspects of services and fail to examine the relational aspects of care. This qualitative study examines patients’ experiences of OPAT. Design In-depth, semistructured interviews. Setting Purposive sample of OPAT patients recruited from four acute National Health Service (NHS) Trusts in Northern England. These NHS Trusts between them represented both well-established and recently set-up services running nurse at home, hospital outpatient and/or selfadministration models. Participants We undertook 28 semistructured interviews and one focus group (n=4). Results Despite good patient outcomes, experiences were coloured by patients' personal situation and material circumstances. Many found looking after themselves at home more difficult than they expected, while others continued to work despite their infection. Expensive car parking, late running services and the inconvenience of waiting in for the nurse to arrive frustrated patients, while efficient services, staffed by nurses with the specialist skills needed to manage intravenous treatment had the opposite effect. Many patients felt a local, general practitioner or community health centre based service would resolve many of the practical difficulties that made OPAT inconvenient. Patients could find OPAT anxiety provoking but this could be ameliorated by staff taking the time to reassure patients and provide tailored information. Conclusion Services configurations must accommodate the diversity of the local population. Poor communication can leave patients lacking the confidence needed to be a competent collaborator in their own care and affect their perceptions of the service

Correction: Life and bladder cancer: protocol for a longitudinal and cross-sectional patient-reported outcomes study of Yorkshire (UK) patients

© Author(s) (or their employer(s)) 2019. This article was previously published with an error in figures. The correct figures are below: Figure 1: Study data flow for the longitudinal study (workstream 2). NCRAS, National Cancer Registration and Analysis. (Figure Presented). Figure 2: Study data flow for the cross-sectional study (workstream 3). CRFs, case report forms; PHE, Public Health England; PIS, patient information sheet. (Figure Presented)

The effect of windspeed on sea surface temperature retrieval from space

The effect of windspeed on water emissivity, whilst being negligible around normal incidence, becomes significant above angles of about 50-degrees. We calculate the effect of windspeed On retrieved sea surface temperature and show that errors become significant for the potentially very accurate Along Track Scanning Radiometer (ATSR, carried on board ESA's first remote sensing satellite, ERS-1) since brightness temperatures measured at almost-equal-to 56-degrees, as well as those measured at nadir, are used to provide improved atmospheric correction. We show that when an SST retrieval algorithm generated assuming zero windspeed is applied to brightness temperatures calculated for windspeeds of 5, 10 and 15 m/s, a potential error of up to 0.4 K is introduced. Since coincident windspeed data can be obtained from the ERS-1 radar altimeter, accurate correction can be made for this effect and we Provide a Preliminary algorithm for the correction of ATSR SST data