Search

INTRODUCTION: An individual case review was conducted of known diving-related deaths that occurred in Australia in 2010. METHOD: The case studies were compiled using statements from witnesses and reports of the police and coroners. In each case, the particular circumstances of the accident and details from the post-mortem examination, where available, are provided. A root cause analysis was made for each case. RESULTS: There were 20 reported fatalities, one less than the previous year. Five of the victims were female (four scuba divers) and 15 were males. Twelve deaths occurred while snorkelling and/or breath-hold diving, seven while scuba diving (one of whom was using a rebreather), and one diver died while using surface supplied breathing apparatus. At least two breath-hold divers likely drowned as a result of apnoeic hypoxia. Cardiac-related issues were thought to have contributed to the deaths of at least three and possibly five snorkellers, and of at least one, possibly two compressed gas divers. CONCLUSIONS: Snorkelling or diving alone, poor supervision, apnoeic hypoxia, pre-existing medical conditions, lack of recent experience and unfamiliar and/or poorly-functioning equipment were features in several deaths in this series. Reducing delays to CT-scanning and autopsy and coroners' reports documenting that the victim of a drowning was snorkelling or scuba diving at the time are aspects of the investigation of these fatalities that could be improved.

The use of self-assembled gel in biomaterials and drug delivery is an important new area of research, with these novel materials possessing both physical and chemical advantages over current bio-polymers. However, as gel research expands, key elements of the self-assembly process and gel network formation are still poorly understood. If these gels are to be introduced into biological systems, a better model for gelation is needed which incorporates the structural behaviour and molecular interactions, which help define the stability of gels during the initial gelation process and over the long term.A novel family of gelator molecules, tetraalkyl pyromellitamides, were previously thought to be a model gel system and form in a hierarchical process as proposed in literature for other self-assembled gel systems. A range of gels were synthesised and tested to determine the effects of small changes to the molecule on the larger bulk gel. Through AFM and TEM imaging, it was found that the gel system does not follow a linear growth mechanism; instead it is a dynamic material which changes unexpectedly over a week. A large initial structure separates into smaller fibres which ten entangle to form super-structures on the nano-scale. Rheological profiles of the gels showed changes in viscosity and stiffness of the gels as they were aged, along with the differences in the initial gel formation.To examine what is causing these changes in the structure, X-Ray and neutron scattering were used to characterise the individual fibres which make up the larger fibres observed in the microscopy images. This data confirmed that a one-dimensional stacking mechanism was responsible for the fibre formation, and these fibres were effectively stretching out over time. To investigate the inter- and intra-molecular interactions, along with the role of the solvent molecules, a new synthesis was devised to produce per-deuterated gelators. Using solid-state deuterium-NMR, the mobility and orientatio

INTRODUCTION: An individual case review of diving-related deaths reported as occurring in Australia in 2009 was conducted as part of the DAN Asia-Pacific Dive Fatality Reporting Project. METHOD: The case studies were compiled using reports from witnesses, the police and coroners. In each case, the particular circumstances of the accident and details from the post-mortem examination, where available, are provided. RESULTS: In total, there were 21 reported fatalities (two more than in 2008), including 18 males and three females. Twelve deaths occurred while snorkelling and/or breath-hold diving, eight while scuba diving and one while using surface-supply breathing apparatus. Apneic hypoxia continues to be a problem with breath-hold divers and appears to have caused the death of three victims in this series. Cardiac-related issues were thought to have been the disabling injury in the deaths of at least three snorkel divers and at least three scuba divers. One of the victims was a student who became separated from her instructor on an introductory scuba dive in poor visibility. CONCLUSIONS: Apneic hypoxia, pre-existing medical conditions, snorkelling or diving alone, separation and inadequate supervision were once again features in several deaths in this series.