15 year old volens to BMX riding risks

The Queensland Court of Appeal recently heard a case that raised the defence of volenti on fit injuria. By a majority of 2:1 the court held in Leyden v Caboolture Shire Council [2007] QCA 134 (20 April 2007) that the defence of volenti was established and defeated the action in negligence for damages for personal injury. The facts of the case were quite simple. The plaintiff was 15 years old when he was injured at the Bluebell Park which was controlled and managed by the Caboolture Shire Council (the defendant). The park had a BMX track – built and maintained by the defendant. At trial it was held that although the defendant owed a duty of care to entrants, a duty was not owed to the plaintiff. The judge found that the plaintiff was different to other entrants who used facilities provided by a council in a public park. The plaintiff was not relying upon the defendant to provide a BMX track with jumps that were reasonably safe as the evidence was that the track was regularly altered by third parties and the plaintiff knew that. Therefore it was reasoned that the plaintiff was relying upon the ability of the third parties who modified the jump and his own ability to use it, not the ability of the defendant to provide a reasonably safe track (at [10]). The trial judge also held that if a duty was owed, the defence of volenti applied so as to defeat the claim for damages. This was based upon the evidence that the plaintiff knew of the modification of the jump by third parties and knew of the risk. It was held that the plaintiff ‘had the appropriate subjective appreciation of the risk’ (at [11]).

The effect of graded levels of exercise on energy intake and balance in free-living men, consuming their normal diet

Objective: To assess the effect of graded increases in exercised-induced energy expenditure (EE) on appetite, energy intake (EI), total daily EE and body weight in men living in their normal environment and consuming their usual diets. Design: Within-subject, repeated measures design. Six men (mean (s.d.) age 31.0 (5.0) y; weight 75.1 (15.96) kg; height 1.79 (0.10) m; body mass index (BMI) 23.3(2.4) kg/m2), were each studied three times during a 9 day protocol, corresponding to prescriptions of no exercise, (control) (Nex; 0 MJ/day), medium exercise level (Mex; ~1.6 MJ/day) and high exercise level (Hex; ~3.2 MJ/day). On days 1-2 subjects were given a medium fat (MF) maintenance diet (1.6 ´ resting metabolic rate (RMR)). Measurements: On days 3-9 subjects self-recorded dietary intake using a food diary and self-weighed intake. EE was assessed by continual heart rate monitoring, using the modified FLEX method. Subjects' HR (heart rate) was individually calibrated against submaximal VO2 during incremental exercise tests at the beginning and end of each 9 day study period. Respiratory exchange was measured by indirect calorimetry. Subjects completed hourly hunger ratings during waking hours to record subjective sensations of hunger and appetite. Body weight was measured daily. Results: EE amounted to 11.7, 12.9 and 16.8 MJ/day (F(2,10)=48.26; P<0.001 (s.e.d=0.55)) on the Nex, Mex and Hex treatments, respectively. The corresponding values for EI were 11.6, 11.8 and 11.8 MJ/day (F(2,10)=0.10; P=0.910 (s.e.d.=0.10)), respectively. There were no treatment effects on hunger, appetite or body weight, but there was evidence of weight loss on the Hex treatment. Conclusion: Increasing EE did not lead to compensation of EI over 7 days. However, total daily EE tended to decrease over time on the two exercise treatments. Lean men appear able to tolerate a considerable negative energy balance, induced by exercise, over 7 days without invoking compensatory increases in EI.

Obstacle-free range determination for rail track maintenance vehicles

Maintenance trains travel in convoy. In Australia, only the first train of the convoy pays attention to the track sig- nalization (the other convoy vehicles simply follow the preceding vehicle). Because of human errors, collisions can happen between the maintenance vehicles. Although an anti-collision system based on a laser distance meter is already in operation, the existing system has a limited range due to the curvature of the tracks. In this paper, we introduce an anti-collision system based on vision. The two main ideas are, (1) to warp the camera image into an image where the rails are parallel through a projective transform, and (2) to track the two rail curves simultaneously by evaluating small parallel segments. The performance of the system is demonstrated on an image dataset.

Architecture for a free subjectivity : Deleuze and Guattari at the Horizon of the Real

Architecture for a Free Subjectivity reformulates the French philosopher Gilles Deleuze's model of subjectivity for architecture, by surveying the prolific effects of architectural encounter, and the spaces that figure in them. For Deleuze and his Lacanian collaborator Félix Guattari, subjectivity does not refer to a person, but to the potential for and event of matter becoming subject, and the myriad ways for this to take place. By extension, this book theorizes architecture as a self-actuating or creative agency for the liberation of purely "impersonal effects." Imagine a chemical reaction, a riot in the banlieues, indeed a walk through a city. Simone Brott declares that the architectural object does not merely take part in the production of subjectivity, but that it constitutes its own.

A chimeric vitronectin : IGF-I protein supports feeder-cell-free and serum-free culture of human embryonic stem cells

This paper was retracted by the Journal of Stem Cells and Development on February 15, 2013.

Free surface problems for static Coulomb-Mohr granular solids

This paper is concerned with some plane strain and axially symmetric free surface problems which arise in the study of static granular solids that satisfy the Coulomb-Mohr yield condition. Such problems are inherently nonlinear, and hence difficult to attack analytically. Given a Coulomb friction condition holds on a solid boundary, it is shown that the angle a free surface is allowed to attach to the boundary is dependent only on the angle of wall friction, assuming the stresses are all continuous at the attachment point, and assuming also that the coefficient of cohesion is nonzero. As a model problem, the formation of stable cohesive arches in hoppers is considered. This undesirable phenomena is an obstacle to flow, and occurs when the hopper outlet is too small. Typically, engineers are concerned with predicting the critical outlet size for a given hopper and granular solid, so that for hoppers with outlets larger than this critical value, arching cannot occur. This is a topic of considerable practical interest, with most accepted engineering methods being conservative in nature. Here, the governing equations in two limiting cases (small cohesion and high angle of internal friction) are considered directly. No information on the critical outlet size is found; however solutions for the shape of the free boundary (the arch) are presented, for both plane and axially symmetric geometries.

Free surface flow into a horizontal slot with zero gravity

The two-dimensional free surface flow of a finite-depth fluid into a horizontal slot is considered. For this study, the effects of viscosity and gravity are ignored. A generalised Schwarz-Christoffel mapping is used to formulate the problem in terms of a linear integral equation, which is solved exactly with the use of a Fourier transform. The resulting free surface profile is given explicitly in closed-form.

Survey of novice motorcycle riders and their riding experience before licensing

Graduated licensing schemes have been found to reduce the crash risk of young novice drivers, but there is less evidence of their success with novice motorcycle riders. This study examined the riding experience of a sample of Australian learner-riders to establish the extent and variety of their riding practice during the learner stage. Riders completed an anonymous questionnaire at a compulsory rider-training course for the licensing test. The majority of participants were male (81%) with an average age of 33 years. They worked full time (81%), held an unrestricted driver's license (81%), and owned the motorcycle that they rode (79%). These riders had held their learner's license for an average of 6 months. On average, they rode 6.4 h/week. By the time they attempted the rider-licensing test, they had ridden a total of 101 h. Their total hours of on-road practice were comparable to those of learner-drivers at the same stage of licensing, but they had less experience in adverse or challenging road conditions. A substantial proportion had little or no experience of riding in the rain (57%), at night (36%), in heavy traffic (22%), on winding rural roads (52%), or on high-speed roads (51%). These findings highlight the differences in the learning processes between unsupervised novice motorcycle riders and supervised novice drivers. Further research is necessary to clarify whether specifying the conditions under which riders should practice during the graduated licensing process would likely reduce or increase their crash risk.

Slum free India program. Report on the findings and recommendations of QUT BEE workshop to investigate strategies to deliver better outcomes

As a result of a broad invitation extended by Professor Martin Betts, Executive Dean of the Faculty of Built Environment and Engineering, to the community of interest at QUT, a cross-disciplinary collaborative workshop was conducted to contribute ideas about responding to the Government of India’s urgent requirement to implement a program to re-house slum dwellers. This is a complex problem facing the Indian Ministry of Housing. Not only does the government aspire to eradicate existing slum conditions and to achieve tangible results within five years, but it must also ensure that slums do not form in the future. The workshop focused on technological innovation in construction to deliver transformation from the current unsanitary and overcrowded informal urban settlements to places that provide the economically weaker sections of Indian society with healthy, environmentally sustainable, economically viable mass housing that supports successful urban living. The workshop was conducted in two part process as follows: Initially, QUT academics from diverse fields shared current research and provided technical background to contextualise the challenge at a pre-workshop briefing session. This was followed by a one-day workshop during which participants worked intensively in multi-disciplinary groups through a series of exercises to develop innovative approaches to the complex problem of slum redevelopment. Dynamic, compressed work sessions, interspersed with cross-functional review and feedback by the whole group took place throughout the day. Reviews emphasised testing the concepts for their level of complexity, and likelihood of success. The two-stage workshop process achieved several objectives:  Inspired a sense of shared purpose amongst a diverse group of academics  Built participants’ knowledge of each other’s capacity  Engaged multi disciplinary team in an innovative design research process  Built participants’ confidence in the collaborative process  Demonstrated that collaborative problem solving can create solutions that represent transformative change.  Developed a framework of how workable solutions might be developed for the program through follow up workshops and charrettes of a similar nature involving stakeholders drawn from the context of the slum housing program management.

Novice riders and the predictors of riding without motorcycle protective clothing

Background While helmet usage is often mandated, few motorcycle and scooter riders make full use of protection for the rest of the body. Little is known about the factors associated with riders’ usage or non-usage of protective clothing. Methods Novice riders were surveyed prior to their provisional licence test in NSW, Australia. Questions related to usage and beliefs about protective clothing, riding experience and exposure, risk taking and demographic details. Multivariable Poisson regression models were used to identify factors associated with two measures of usage, comparing those who sometimes vs rarely/never rode unprotected and who usually wore non-motorcycle pants vs motorcycle pants. Results Ninety-four percent of eligible riders participated and usable data was obtained from 66% (n = 776). Factors significantly associated with riding unprotected were: youth (17–25 years) (RR = 2.00, 95% CI: 1.50–2.65), not seeking protective clothing information (RR = 1.29, 95% CI = 1.07–1.56), non-usage in hot weather (RR = 3.01, 95% CI: 2.38–3.82), awareness of social pressure to wear more protection (RR = 1.48, 95% CI: 1.12–1.95), scepticism about protective benefits (RR = 2.00, 95% CI: 1.22–3.28) and riding a scooter vs any type of motorcycle. A similar cluster of factors including youth (RR = 1.17, 95% CI: 1.04–1.32), social pressure (RR = 1.32, 95% CI: 1.16–1.50), hot weather (RR = 1.30, 95% CI: 1.19–1.41) and scooter vs motorcycles were also associated with wearing non-motorcycle pants. There was no evidence of an association between use of protective clothing and other indicators of risk taking behaviour. Conclusions Factors strongly associated with non-use of protective clothing include not having sought information about protective clothing and not believing in its injury reduction value. Interventions to increase use may therefore need to focus on development of credible information sources about crash risk and the benefits of protective clothing. Further work is required to develop motorcycle protective clothing suitable for hot climates.