Edge delineations

In 2001, the Motor Accident Commission (MAC) sponsored a trial of a comparatively inexpensive form of audio tactile raised pavement marker as a fatigue driving countermeasure on the Dukes Highway east of Keith, South Australia. MAC has asked the Centre for Automotive Safety Research (CASR) to comment on the relevance of this treatment including its compliance with road design rules, its cost effectiveness when compared to other treatments and any safety issue with their useJ.E. Woolley and A.J. McLea

Evaluation of the South Australian default 50 km/h speed limit

On 1 March 2003 the default urban speed limit in South Australia was reduced from 60 km/h to 50 km/h. On-road speeds just before the default limit was introduced were compared with speeds a year later. The numbers of casualty crashes and casualties in the year before the default limit was introduced were compared with the corresponding numbers in the first year that the default limit was in effect. On roads where the speed limit was reduced from 60 km/h to 50 km/h, average vehicle speeds decreased by 2.3 km/h and casualties by 24 per cent. On roads where the speed limit remained at 60 km/h, average vehicle speeds decreased by 0.9 km/h and casualties by 7 per cent.C.N. Kloeden, J.E. Woolley and A.J. McLea

Further evaluation of the South Australian default 50 km/h speed limit

On 1 March 2003 the default urban speed limit in South Australia was reduced from 60 km/h to 50 km/h. On-road speeds just before the default limit was introduced were compared with speeds one and three years later. The number of casualty crashes and casualties in the three years before the default limit was introduced were compared with corresponding numbers in the three years after the default limit came into effect. On roads where the speed limit was reduced from 60 km/h to 50km/h, average speeds decreased by 3.8km/h after three years and casualty crashes fell by 23 per cent. On roads where the speed limit remained at 60 km/h, average vehicle speeds decreased by 2.1 km/h after three years and casualty crashes fell by 16 per cent.C.N. Kloeden, J.E. Woolley and A.J. McLea

Impacts of lower speed limits in South Australia

ustralia has recently undergone a change of urban speed limits in most of its jurisdictions. The political and social shift in attitudes required for this change is significant in a country that has a strong reliance on the use of the private motor vehicle. At present five states and one territory have lowered the speed limit in urban areas from 60km/h to 50km/h. Of the remaining two states and territories, one has already implemented lower speed limits (40km/h) in small areas within cities. In the majority of cases, the only criterion for judging the success of such schemes is an observed reduction in both speeds and crash numbers. This paper reports on a more holistic assessment of such schemes taking into account factors in addition to speed and crashes including: traffic volume displacement, physical road network characteristics, environmental factors, community ownership and acceptance, enforcement effort and impact on travel times. The research work has included the analysis of extensive traffic data, community surveys and focus groups, the collection of environmental and travel time data from an instrumented probe vehicle and the computer modelling of road networks. The work reported is based on over 10 years of working with a 40km/h lower urban speed limit area in South Australia. The paper expands the notion of using speed and crash outcomes as the only criteria for measuring the success of lower speed limit schemes. Document type: Articl

Hemodynamic variability and cerebrovascular control after transient cerebral ischemia

We investigated if hemodynamic variability, cerebral blood flow (CBF) regulation, and their interrelationships differ between patients with transient ischemic attack (TIA) and controls. We recorded blood pressure (BP) and bilateral middle cerebral artery flow velocity (MCAv) in a cohort of TIA patients (n = 17), and age?matched controls (n = 15). Spontaneous fluctuations in BP and MCAv were characterized by spectral power analysis, and CBF regulation was assessed by wavelet phase synchronization analysis in the very low? (0.02–0.07 Hz), low? (0.07–0.20 Hz), and high?frequency (0.20–0.40 Hz) ranges. Furthermore, cerebrovascular CO2 reactivity was assessed as a second metric of CBF regulation by inducing hypercapnia with 8% CO2 inhalation followed by hyperventilation driven hypocapnia. We found that TIA was associated with higher BP power (group effect, P < 0.05), but not MCAv power (P = 0.11). CBF regulation (assessed by wavelet phase synchronization and CO2 reactivity) was intact in patients (all P ? 0.075) across both hemispheres (all P ? 0.51). Pooled data (controls and affected hemisphere of patients) showed that BP and MCAv power were positively correlated at all frequency ranges (R2 = 0.20–0.80, all P < 0.01). Furthermore, LF phase synchronization index was a significant determinant of MCAv power (P < 0.05), while VLF and HF phase synchronization index, and TIA were not (all P ? 0.50). These results indicate that CBF stability and control is maintained in TIA patients, but BPV is markedly elevated. BPV attenuation may be an important therapeutic strategy for enhancing secondary stroke prevention in patients who suffer a TIA

Annual performance indicators of enforced driver behaviours in South Australia, 2003

The Centre for Automotive Safety Research at the University of Adelaide was commissioned by the Department for Transport, Energy and Infrastructure to produce a report quantifying performance indicators for selected enforced driver behaviours (drink driving, speeding, restraint use) in South Australia for the calendar year 2003. The total number of breath tests conducted in South Australia in 2003 was 11 percent lower than the level in 2002. However, mobile RBT was introduced for the first time, late in the year, and was found to be a better means of detecting drink drivers than static RBT. Also, spending on anti-drink driving publicity increased markedly in 2003. The year 2003 was significant for the reductions in speed limits introduced in South Australia. Total hours of speed detection decreased by 11 percent, however, due to a marked decrease in the hours of operation of speed cameras in the metropolitan area. The reduction in the use of highly efficient speed cameras was the likely explanation for a 27 percent reduction in the number of drivers charged with speeding offences in 2003. An evaluation of the effect of the reduction in the default urban speed limit revealed that speeds decreased on all roads affected by the change but also, by a smaller magnitude, on arterial roads on which the 60 km/h limit was maintained. Restraint offences increased slightly in 2003 but there were no observational surveys conducted to provide an indication of restraint wearing rates, and so the slight increase in offences could have been due to differences in enforcement. Males were again over-represented in restraint offences and in non-restrained vehicle occupants injured in crashes. The amount of money spent on publicity for restraint use in 2003 was significantly greater than previous years

Compounding barriers to fairness in the digital technology ecosystem

A growing sense of unfairness permeates our quasi-digital society. Despite drivers supporting and motivating ethical practice in the digital technology ecosystem, there are compounding barriers to fairness that, at every level, impact technology innovation, delivery and access. Amongst these are barriers and omissions at the earliest stages of technology intentionality and design; systemic inadequacies in sensing systems that deteriorate performance for individuals based on ethnicity, age and physicality; system design, co-requisite and interface decisions that limit access; biases and inequities in datasets and algorithms; and limiting factors in system function and security. Additionally, there are concerns about unethical and illegal practices amongst digital technology providers: for example, in planned obsolescence and anti-competitive behaviors, failings in data practices and security, and in responses to problematic use and behaviors. It is critical that these failings are identified and addressed to better evolve a fairer future digital technology ecosystem. This paper contributes a perspective on technological stewardship and innovation; it identifies the compounding nature of barriers to fairness in the current digital technology ecosystem, and contrasts these with the non-compounding fairness drivers that, in general, establish minimum requirements

Interaction of substance P with phospholipid bilayers: A neutron diffraction study

AbstractNeutron diffraction has been used to study the membrane-bound structure of substance P (SP), a member of the tachykinin family of neuropeptides. The depth of penetration of its C-terminus in zwitterionic and anionic phospholipid bilayers was probed by specific deuteration of leucine 10, the penultimate amino acid residue. The results show that the interaction of SP with bilayers, composed of either dioleoylphosphatidylcholine (DOPC), or a 50:50 mixture of DOPC and the anionic phospholipid dioleoylphosphatidylglycerol (DOPG), takes place at two locations. One requires insertion of the peptide into the hydrophobic region of the bilayer, the other is much more peripheral. The penetration of the peptide into the hydrophobic region of the bilayer is reflected in a marked difference in the water distribution profiles. SP is seen to insert into DOPC bilayers, but a larger proportion of the peptide is found at the surface when compared to the anionic bilayers. The positions of the two label populations show only minor differences between the two types of bilayer

Safety and feasibility of apheresis to harvest and concentrate parasites from subjects with induced blood stage Plasmodium vivax infection

Background: In the absence of a method to culture Plasmodium vivax, the only way to source parasites is ex vivo. This hampers many aspects of P. vivax research. This study aimed to assess the safety of apheresis, a method for selective removal of specific components of blood as a means of extracting and concentrating P. vivax parasites. Methods: An iterative approach was employed across four non-immune healthy human subjects in single subject cohorts. All four subjects were inoculated with ~ 564 blood stage P. vivax (HMP013-Pv) and subjected to apheresis 10 to 11 days later. Blood samples collected during apheresis (haematocrit layers 0.5% to 11%) were tested for the presence and concentration of P. vivax by microscopy, flow cytometry, 18S rDNA qPCR for total parasites, and pvs25 qRT-PCR for female gametocyte transcripts. Safety was determined by monitoring adverse events. Malaria transmission to mosquitoes was assessed by membrane feeding assays. Results: There were no serious adverse events and no significant safety concerns. Apheresis concentrated asexual parasites by up to 4.9-fold (range: 0.9–4.9-fold) and gametocytes by up to 1.45-fold (range: 0.38–1.45-fold) compared to pre-apheresis densities. No single haematocrit layer contained > 40% of all the recovered P. vivax asexual parasites. Ex vivo concentration of parasites by Percoll gradient centrifugation of whole blood achieved greater concentration of gametocytes than apheresis. Mosquito transmission was enhanced by up to fivefold in a single apheresis sample compared to pre-apheresis. Conclusion: The modest level of parasite concentration suggests that the use of apheresis may not be an ideal method for harvesting P. vivax. Trial Registration Australia New Zealand Clinical Trials Registry (ANZCTR) Trial ID: ACTRN12617001502325 registered on 19th October 2017. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373812

Ultrafast optoelectronic processes in 1D radial van der Waals heterostructures : carbon, boron nitride, and MoS 2 nanotubes with coexisting excitons and highly mobile charges

Heterostructures built from 2D, atomically thin crystals are bound by the van der Waals force and exhibit unique optoelectronic properties. Here, we report the structure, composition and optoelectronic properties of 1D van der Waals heterostructures comprising carbon nanotubes wrapped by atomically thin nanotubes of boron nitride and molybdenum disulfide (MoS2). The high quality of the composite was directly made evident on the atomic scale by transmission electron microscopy, and on the macroscopic scale by a study of the heterostructure’s equilibrium and ultrafast optoelectronics. Ultrafast pump−probe spectroscopy across the visible and terahertz frequency ranges identified that, in the MoS 2 nanotubes, excitons coexisted with a prominent population of free charges. The electron mobility was comparable to that found in high-quality atomically thin crystals. The high mobility of the MoS2 nanotubes highlights the potential of 1D van der Waals heterostructures for nanoscale optoelectronic devices