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Objective: There are increasing numbers of shark attacks in Australasian waters, with death commonly resulting from uncontrolled lower limb bleeding. The present study aims to determine the most effective first aid method using immediately available resources for controlling lower limb haemorrhage, which could be provided by single unsupported rescuer. Methods: The present study was a clinical trial performed at a single tertiary referral hospital. Healthy volunteers who completed a screening questionnaire, a baseline popliteal velocity measurement and then consented were eligible. The present study used Doppler ultrasound to record the reduction in popliteal artery peak systolic velocity created by surfboard leg rope tourniquet and by inguinal region external compression in healthy volunteer subjects with and without a wetsuit. Leg circumference and sex data were also collected. Results: Pooled data from each intervention without and with a wetsuit showed that inguinal compression resulted in a mean reduction of popliteal artery peak systolic velocity of 89.7% (95% CI 83.9%, 95.5%) compared to leg rope application 43.8% (95% CI 34.5%, 53.1%; P ≤ 0.001). There was no significant influence by the wetsuit on effectiveness of either intervention technique. Conclusion: The present study has shown that manual inguinal compression, an easily taught first aid technique, can reliably completely stop or substantially reduce blood loss in the setting of a lower limb injury and is superior to an improvised tourniquet. [ABSTRACT FROM AUTHOR]

ABSTRACT: Flash autoclaving is one of the most frequently utilized methods of sterilizing devices, implants or other materials. For a number of decades, it has been common practice for surgeons to remove implantable devices, flash autoclave and then reimplant them in a patient. Data have not yet indicated the potential for biofilms to survive or remain on the surface of orthopaedic‐relevant materials following flash autoclave. In this study, monomicrobial and polymicrobial biofilms were grown on the surface of clinically relevant titanium materials and exposed to flash autoclave settings that included varying times and temperatures. Data indicated that when the sterilization and control temperatures of an autoclave were the same, biofilms were able to survive flash autoclaving that was performed for a short duration. Higher temperature and increased duration rendered biofilms non‐viable, but none of the autoclave settings had the ability to remove or disperse the presence of biofilms from the titanium surfaces. These findings may be beneficial for facilities, clinics, or hospitals to consider if biofilms are suspected to be present on materials or devices, in particular implants that have had associated infection and are considered for re‐implantation. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1543–1550, 2018. [ABSTRACT FROM AUTHOR]

Predicting the risk of traffic demands and delays exceeding critical limits at road junctions, airports, hospitals, etc., requires knowing how both mean and variance of queue size vary over time. Microscopic simulation can explore variability but is computationally demanding and gives only sample results. A computationally efficient approximation to the mean is used in many modelling tools, but only empirical extensions for variance in particular situations have been available. The paper derives theoretical formulae for time-dependent and equilibrium variance, believed to be novel and to apply generally to queues covered by the Pollaczek–Khinchin mean formula, and offering possible structural insights. These are applied in an extended approximation giving mutually consistent mean and variance estimates with improved accuracy. Tests on oversaturated peak demand cases are compared with Markov probabilistic simulation, demonstrating accuracy (R2 > 0.99) for typical random, priority-like (M/M/1) and traffic-signal-like (M/D/1) queues. Implications for risk analysis, planning and policy are considered. [ABSTRACT FROM AUTHOR]

Queues are often associated with uncertainty or unreliability, which can arise from chance or climatic events, phase changes in system behaviour, or inherent randomness. Knowing the probability distribution of the number of customers in a queue is important for estimating the risk of stress or disruption to routine services and upstream blocking, potentially leading to exceeding critical limits, gridlock or incidents. The present paper focuses on time-varying queues produced by transient oversaturation during demand peaks where there is randomness in arrivals and service. The objective is to present practical methods for estimating a probability distribution from knowledge of the mean, variance and utilisation (degree of saturation) of a queue available from computationally efficient, if approximate, time-dependent calculation. This is made possible by a novel expression for time-dependent queue variance. The queue processes considered are those commonly used to represent isolated priority (M/M/1) and signal-like (M/D/1) systems, plus some statistical variations within the common Pollaczek-Khinchin framework. Results are verified by comparison with Markov simulation based on recurrence relations. [ABSTRACT FROM AUTHOR]

Many analyses of traffic signal queues use Webster and Cobbe's formula, which combines the net effect of the red/green cycle with a term representing stochastic effects, idealised as an M/D/1 queue process having random arrivals and uniform service. Several authors have noted that this component should depend not only on demand intensity but also on throughput capacity in each green period, although an extra empirical term may partially allow for this. Extending the service interval in M/D/1 (M = Markovian, i.e. random, D = deterministic, i.e. uniform, 1 = one server) enables the effect to be reproduced, but no exact expressions for its moments are found. Approximate formulae for the extended mean exist but are accurate only near saturation. The paper derives novel approximations for the equilibrium mean and also variance and utilisation, using functions linking traffic intensity with green period capacity. With three moments, equilibrium probability distributions can be estimated for which a method based on a doubly nested geometric distribution is described. [ABSTRACT FROM PUBLISHER]

Pressure on transport networks from increased demand to travel combined with reducing investment in highway infrastructure is leading to significant interest in the use of transport telematics. Telematics systems are aimed at making the most of existing infrastructure through, for example, area traffic control, electronic tolling and traveller information. Although there are quite high levels of activity in the application and implementation of some systems, there remains a significant dearth of evidence of the impact these systems will have on behaviour and travel patterns. It is important that appropriate appraisal methodologies are available to assess the impact of new systems. Modelling is an appropriate method of appraisal as it enables system-wide impacts of individual responses to be predicted. This paper is concerned with the advances required in order that modelling techniques are available for this purpose. Modelling requirements are identified from reviews of technologies, behavioural responses and modelling procedures. Advice is given on both enhancements to existing modelling procedures and the structure of a modelling system that fully meets assessment needs. Recommendations are made on steps to be taken towards this. [ABSTRACT FROM AUTHOR]