A portable data acquisition system for the measurement of impact attenuation of playground surfacing

Gone are the days when childrens playgrounds were erected on concrete and asphalt. Impact attenuating playground surfacing has been common place in most childrens playgrounds for many years. Unfortunately there is not a strong correlation between the expected reduction in the frequency and severity of playground injuries. Until recently testing of playground undersurfacing was restricted to the laboratory. This paper details the development and description of a portable data acquisition system for use in playgrounds

Vibration measurement as a tool to solve a murder

This paper will discuss a novel use of vibration measurement used to assist the NSW Police Force to solve the ‘pogo stick’ murder. The authors were approached by the Homicide Squad regarding a suspicious death of a 7-year boy at Oatley in May 2013. The child had reportedly fallen from a pogo stick and suffered significant head injuries. The child had not been provided with medical attention after the fall and died some 24 hours later. The incident occurred inside a small unit which was used as a music recording studio. The studio is on the first level of a larger business complex. The studio consisted of a recording room, a lounge room, and a kitchenette. The child fell in the lounge room. At the time of the alleged incident the mother was in the kitchenette, and the accused was in the recording room. According to the accused, he had headphones on and was listening to loud music when he 'felt' the vibration of the thud. Kodi Maybir was found guilty of murder in November 2015

Double bounce vibration on trampolines and associated injuries

By observing usage and reviewing accident data it is clear that multiple-user trampoline double-bouncing creates highly dangerous situations. An understanding of this phenomenon’s characteristics has not been fully researched. Observation indicate that under certain circumstances there is the potential for a high transfer of energy from one user to another, leading to surprisingly higher launch heights, which result in landing and compression injuries. Medicine balls of various weights, heights and impact location were released from above a trampoline mat to simulate user impact. The quick release mechanisms were controlled by electronic triggers to eliminate any undesired variances in impact timing between tests, allowing for reliable, repeatable testing. A calibrated video analysis is the primary means of data collection. Due to the unpredictable nature of double-bouncing, users are often unable to anticipate the occurrence of a double-bounce, meaning they are physically unprepared or braced for the immense acceleration forces generated by the transfer of energy. This paper presents the experimental findings of trampoline double-bouncing and quantifies the conditions which allow the high energy-transfer rates that lead to multi-user injuries

Reducing playground injuries by increasing HIC sampling rate from 8 kHz to 20 kHz

Impact attenuating surface (IAS) materials are used in children's playgrounds to limit the potential impact hazard presented to a child when falling from playground equipment; the largest hazard being head impact injuries. The head injury criterion (HIC) is used to measure the IAS around the world. Australia adopted a sampling rate of 8 kHz for playground IAS testing in 1996 from automotive industry testing for measurement of the HIC. Data acquisition has improved since 1996 and it is important that the performance of the IAS is measured accurately. An investigation into the effects of sampling rate on the HIC value was undertaken. A variety of IAS samples were impact tested at sampling rates ranging from 8 kHz to 80 kHz using a calibrated hemispherical headform fitted with a tri-axial accelerometer. The results of this testing will be presented. The testing confirmed that a sampling rate of 8 kHz under reported the HIC particularly at the critical fall height of IAS. Australia adopted a sampling rate of 20 kHz on the 23 November 2016 when they published AS 4422:2016

The ball in play demands of international rugby union

Objectives: Rugby union is a high intensity intermittent sport, typically analysed via set time periods or rolling average methods. This study reports the demands of international rugby union via global positioning system (GPS) metrics expressed as mean ball in play (BiP), maximum BiP (max BiP), and whole match outputs. Design: Single cohort cross sectional study involving 22 international players, categorised as forwards and backs. Methods: A total of 88 GPS files from eight international test matches were collected during 2016. An Opta sportscode timeline was integrated into the GPS software to split the data into BiP periods. Metres per min (m.min-1), high metabolic load per min (HML), accelerations per min (Acc), high speed running per min (HSR), and collisions per min (Coll) were expressed relative to BiP periods and over the whole match (>60min). Results: Whole match metrics were significantly lower than all BiP metrics (p < 0.001). Mean and max BiP HML, (p < 0.01) and HSR (p < 0.05) were significantly higher for backs versus forwards, whereas Coll were significantly higher for forwards (p < 0.001). In plays lasting 61s or greater, max BiP m.min-1 were higher for backs. Max BiP m.min-1, HML, HSR and Coll were all time dependant (p < 0.05) showing that both movement metrics and collision demands differ as length of play continues. Conclusions: This study uses a novel method of accurately assessing the BiP demands of rugby union. It also reports typical and maximal demands of international rugby union that can be used by practitioners and scientists to target training of worst-case scenario's equivalent to international intensity. Backs covered greater distances at higher speeds and demonstrated higher HML, in general play as well as 'worst case scenarios'; conversely forwards perform a higher number of collisions

Statistically-secure ORAM with O~(log⁡2n)\tilde{O}(\log^2 n) Overhead

We demonstrate a simple, statistically secure, ORAM with computational overhead $\tilde{O}(\log^2 n)$; previous ORAM protocols achieve only computational security (under computational assumptions) or require $\tilde{\Omega}(\log^3 n)$ overheard. An additional benefit of our ORAM is its conceptual simplicity, which makes it easy to implement in both software and (commercially available) hardware. Our construction is based on recent ORAM constructions due to Shi, Chan, Stefanov, and Li (Asiacrypt 2011) and Stefanov and Shi (ArXiv 2012), but with some crucial modifications in the algorithm that simplifies the ORAM and enable our analysis. A central component in our analysis is reducing the analysis of our algorithm to a "supermarket" problem; of independent interest (and of importance to our analysis,) we provide an upper bound on the rate of "upset" customers in the "supermarket" problem

Understanding the social inclusion needs of people living in mental health supported accommodation

Objectives: To identify the social inclusion needs that were (i) most commonly identified and (ii) most and least commonly prioritised as support planning goals for mental health service users living in supported accommodation, using the online Social Inclusion Questionnaire User Experience (SInQUE). We qualitatively examined mental health supported accommodation staff and servicer users’ views on barriers to offering support with two less commonly prioritised areas: help finding a partner and feeling less lonely. // Methods: Anonymous SInQUE data were collected during a completed study in which we developed and tested the online SInQUE. Four focus groups were conducted with mental health supported accommodation staff (N = 2) and service users (N = 2). // Results: The most common social inclusion needs identified by service users (N = 31) were leisure activities, finding transport options, and feeling less lonely. Of the needs identified, those that service users and staff least frequently prioritised as support planning goals were having company at mealtimes, getting one’s own furniture, feeling less lonely, help with finances, and help finding a partner. In the focus groups, staff and service users identified barriers to helping with loneliness and finding a partner which related to staff and service users themselves, supported accommodation services, and wider societal factors

Dynamic Behaviour of High Performance of Sand Surfaces Used in the Sports Industry

The sand surface is considered a critical injury and performance contributing factor in different sports, from beach volleyball to greyhound racing. However, there is still a significant gap in understanding the dynamic behaviour of sport sand surfaces, particularly their vibration behaviour under impact loads. The purpose of this research was to introduce different measurement techniques to the study of sports sand surface dynamic behaviour. This study utilised an experimental drop test, accelerometry, in-situ moisture content and firmness data, to investigate the possible correlation between the sand surface and injuries. The analysis is underpinned by data gathered from greyhound racing and discussed where relevant.</jats:p

Phase II assessment of talabostat and cisplatin in second-line stage IV melanoma

<p>Abstract</p> <p>Background</p> <p>Metastatic melanoma is an incurable disease with an average survival of less than one year. Talabostat is a novel dipeptidyl peptidase inhibitor with immunostimulatory properties.</p> <p>Methods</p> <p>This phase II, open label, single arm study was conducted to evaluate the safety and efficacy of 75–100 mg/m²cisplatin combined with 300–400 mcg talabostat bid for 6, 21-day cycles. The primary endpoint was overall response. The rate of complete responses, duration of overall objective response, progression-free survival (PFS), and overall survival were the secondary endpoints.</p> <p>Results</p> <p>Six objective partial responses were recorded in the 74 patients (8.1%) in the intention-to-treat population. Five of these responses involved the 40 evaluable patients (12.5%). Thirty-one percent of patients reported SAEs to the combination of talabostat and cisplatin.</p> <p>Conclusion</p> <p>Acceptable tolerability was observed in the intention-to-treat population and antitumor activity was observed in 12.5% of evaluable patients, which is not greater than historical expectation with cisplatin alone.</p