On the commonly accepted assumptions regarding observed motor vehicle crash counts at transport system locations

Readily accepted knowledge regarding crash causation is consistently omitted from efforts to model and subsequently understand motor vehicle crash occurrence and their contributing factors. For instance, distracted and impaired driving accounts for a significant proportion of crash occurrence, yet is rarely modeled explicitly. In addition, spatially allocated influences such as local law enforcement efforts, proximity to bars and schools, and roadside chronic distractions (advertising, pedestrians, etc.) play a role in contributing to crash occurrence and yet are routinely absent from crash models. By and large, these well-established omitted effects are simply assumed to contribute to model error, with predominant focus on modeling the engineering and operational effects of transportation facilities (e.g. AADT, number of lanes, speed limits, width of lanes, etc.) The typical analytical approach—with a variety of statistical enhancements—has been to model crashes that occur at system locations as negative binomial (NB) distributed events that arise from a singular, underlying crash generating process. These models and their statistical kin dominate the literature; however, it is argued in this paper that these models fail to capture the underlying complexity of motor vehicle crash causes, and thus thwart deeper insights regarding crash causation and prevention. This paper first describes hypothetical scenarios that collectively illustrate why current models mislead highway safety researchers and engineers. It is argued that current model shortcomings are significant, and will lead to poor decision-making. Exploiting our current state of knowledge of crash causation, crash counts are postulated to arise from three processes: observed network features, unobserved spatial effects, and ‘apparent’ random influences that reflect largely behavioral influences of drivers. It is argued; furthermore, that these three processes in theory can be modeled separately to gain deeper insight into crash causes, and that the model represents a more realistic depiction of reality than the state of practice NB regression. An admittedly imperfect empirical model that mixes three independent crash occurrence processes is shown to outperform the classical NB model. The questioning of current modeling assumptions and implications of the latent mixture model to current practice are the most important contributions of this paper, with an initial but rather vulnerable attempt to model the latent mixtures as a secondary contribution.

A comparison of perceived crash risk among cyclists and drivers in Brisbane

The Queensland Government has implemented strategies promoting a shift from individual car use to active transport, a transition which requires drivers to adapt to sharing the road with increased numbers of people cycling through transport network. For this to occur safely, changes in both road infrastructure and road user expectations and behaviors will be needed. Creating separate cycle infrastructure does not remove the need for cyclists to commence, cross or finish travel on shared roads. Currently intersections are one of the predominant shared road spaces where crashes result in cyclists being injured or killed. This research investigates how Brisbane cyclists and drivers perceive risk when interacting with other road users at intersections. The current study replicates a French study conducted by co-authors Chaurand and Delhomme in 2011 and extends it to assess gender effects which have been reported in other Australian cycling research. An online survey was administered to experienced cyclists and drivers. Participants rated the level of risk they felt when imagining a number of different road situations. Based on the earlier French study it is expected that perceived crash risk will be influenced both by the participant’s mode of travel and the type of interacting vehicle and perceived risk will be greater when the interaction is with a car than a bicycle. It is predicted that risk perception will decrease as the level of experience increases and that male participants will have a higher perception of skill and lower perception of risk than females. The findings of this Queensland study will provide a valuable insight into perceived risk and the traffic behaviours of drivers and cyclists when interacting with other road users and results will be available for presentation at the Congress.

Multilevel determinants of breast cancer survival : association with geographic remoteness and area-level socioeconomic disadvantage

A major priority for cancer control agencies is to reduce geographical inequalities in cancer outcomes. While the poorer breast cancer survival among socioeconomically disadvantaged women is well established, few studies have looked at the independent contribution that area- and individual-level factors make to breast cancer survival. Here we examine relationships between geographic remoteness, area-level socioeconomic disadvantage and breast cancer survival after adjustment for patients’ socio- demographic characteristics and stage at diagnosis. Multilevel logistic regression and Markov chain Monte Carlo simulation were used to analyze 18 568 breast cancer cases extracted from the Queensland Cancer Registry for women aged 30 to 70 years diagnosed between 1997 and 2006 from 478 Statistical Local Areas in Queensland, Australia. Independent of individual-level factors, area-level disadvantage was associated with breast-cancer survival (p=0.032). Compared to women in the least disadvantaged quintile (Quintile 5), women diagnosed while resident in one of the remaining four quintiles had significantly worse survival (OR 1.23, 1.27, 1.30, 1.37 for Quintiles 4, 3, 2 and 1 respectively).) Geographic remoteness was not related to lower survival after multivariable adjustment. There was no evidence that the impact of area-level disadvantage varied by geographic remoteness. At the individual level, Indigenous status, blue collar occupations and advanced disease were important predictors of poorer survival. A woman’s survival after a diagnosis of breast cancer depends on the socio-economic characteristics of the area where she lives, independently of her individual-level characteristics. It is crucial that the underlying reasons for these inequalities be identified to appropriately target policies, resources and effective intervention strategies.

Survival, sublethal injury and recovery of environmental Burkholderia pseudomallei in soil subjected to desiccation

Environmental Burkholderia pseudomallei isolated from sandy soil at Castle Hill, Townsville, in the dry tropic region of Queensland, Australia, was inoculated into sterile-soil laboratory microcosms subjected to variable soil moisture. Survival and sublethal injury of the B. pseudomallei strain were monitored by recovery using culture-based methods. Soil extraction buffer yielded higher recoveries as an extraction agent than sterile distilled water. B. pseudomallei was not recoverable when inoculated into desiccated soil but remained recoverable from moist soil subjected to 91 days desiccation and showed a growth response to increased soil moisture over at least 113 days. Results indicate that endemic dry tropic soil may act as a reservoir during the dry season, with an increase in cell number and potential for mobilization from soil into water in the wet season.

Comparing cooperative and non-cooperative crash risk assessment

Cooperative Systems provide, through the multiplication of information sources over the road, a lot of potential to improve the assessment of the road risk describing a particular driving situation. In this paper, we compare the performance of a cooperative risk assessment approach against a non-cooperative approach; we used an advanced simulation framework, allowing for accurate and detailed, close-to-reality simulations. Risk is estimated, in both cases, with combinations of indicators based on the TTC. For the non-cooperative approach, vehicles are equipped only with an AAC-like forward-facing ranging sensor. On the other hand, for the cooperative approach, vehicles share information through 802.11p IVC and create an augmented map representing their environment; risk indicators are then extracted from this map. Our system shows that the cooperative risk assessment provides a systematic increase of forward warning to most of the vehicles involved in a freeway emergency braking scenario, compared to a non-cooperative system.

SECIS-binding protein 2 promotes cell survival by protecting against oxidative stress

Reactive oxygen species (ROS) are a primary cause of cellular damage that leads to cell death. In cells, protection from ROS-induced damage and maintenance of the redox balance is mediated to a large extent by selenoproteins, a distinct family of proteins that contain selenium in form of selenocysteine (Sec) within their active site. Incorporation of Sec requires the Sec-insertion sequence element (SECIS) in the 3'-untranslated region of selenoproteins mRNAs and the SECIS-binding protein 2 (SBP2). Previous studies have shown that SBP2 is required for the Sec-incorporation mechanism; however, additional roles of SBP2 in the cell have remained undefined. We herein show that depletion of SBP2 by using antisense oligonucleotides (ASOs) causes oxidative stress and induction of caspase- and cytochrome c-dependent apoptosis. Cells depleted of SBP2 have increased levels of ROS, which lead to cellular stress manifested as 8-oxo-7,8-dihydroguanine (8-oxo-dG) DNA lesions, stress granules, and lipid peroxidation. Small-molecule antioxidants N-acetylcysteine, glutathione, and α-tocopherol only marginally reduced ROS and were unable to rescue cells fully from apoptosis, indicating that apoptosis might be directly mediated by selenoproteins. Our results demonstrate that SBP2 is required for protection against ROS-induced cellular damage and cell survival. Antioxid. Redox Signal. 12, 797–808.

Comparison of moped, scooter and motorcycle crash risk and crash severity

The increased popularity of mopeds and motor scooters in Australia and elsewhere in the last decade has contributed substantially to the greater use of powered two-wheelers (PTWs) as a whole. As the exposure of mopeds and scooters has increased, so too has the number of reported crashes involving those PTW types, but there is currently little research comparing the safety of mopeds and, particularly, larger scooters with motorcycles. This study compared the crash risk and crash severity of motorcycles, mopeds and larger scooters in Queensland, Australia. Comprehensive data cleansing was undertaken to separate motorcycles, mopeds and larger scooters in police-reported crash data covering the five years to 30 June 2008. The crash rates of motorcycles (including larger scooters) and mopeds in terms of registered vehicles were similar over this period, although the moped crash rate showed a stronger downward trend. However, the crash rates in terms of distance travelled were nearly four times higher for mopeds than for motorcycles (including larger scooters). More comprehensive distance travelled data is needed to confirm these findings. The overall severity of moped and scooter crashes was significantly lower than motorcycle crashes but an ordered probit regression model showed that crash severity outcomes related to differences in crash characteristics and circumstances, rather than differences between PTW types per se. Greater motorcycle crash severity was associated with higher (>80 km/h) speed zones, horizontal curves, weekend, single vehicle and nighttime crashes. Moped crashes were more severe at night and in speed zones of 90 km/h or more. Larger scooter crashes were more severe in 70 km/h zones (than 60 km/h zones) but not in higher speed zones, and less severe on weekends than on weekdays. The findings can be used to inform potential crash and injury countermeasures tailored to users of different PTW types.

Do we need to use an accountant? The sales growth and survival benefits to family SMEs

This article explores the relationship between the usage of an external accountant and family firm sales growth and survival. Using a longitudinal panel of Australian small and medium sized family enterprises, we find that external accountants have a positive impact on sales growth and survival. We also find that the degree to which the accountant is acquainted with the family and the firm’s needs, which we term as embeddedness, moderates these positive outcomes. Furthermore, we find that appropriate strategic planning processes are necessary to maximize the sales growth benefit; however, these processes are not necessary to gain the survival benefit.

Effects of soluble dietary cellulose on specific growth rate, survival and digestive enzyme activities in three freshwater crayfish (Cherax) species

Three native freshwater crayfish Cherax species are farmed in Australia namely; Redclaw (Cherax quadricarinatus), Marron (C. tenuimanus), and Yabby (C. destructor). Lack of appropriate data on specific nutrient requirements for each of these species, however, has constrained development of specific formulated diets and hence current use of over-formulated feeds or expensive marine shrimp feeds, limit their profitability. A number of studies have investigated nutritional requirements in redclaw that have focused on replacing expensive fish meal in formulated feeds with non-protein, less expensive substitutes including plant based ingredients. Confirmation that freshwater crayfish possess endogenous cellulase genes, suggests their potential ability to utilize complex carbohydrates like cellulose as nutrient sources in their diet. To date, studies have been limited to only C. quadricarinatus and C. destructor and no studies have compared the relative ability of each species to utilize soluble cellulose in their diets. Individual feeding trials of late-juveniles of each species were conducted separately in an automated recirculating culture system over 12 week cycles. Animals were fed either a test diet (TD) that contained 20% soluble cellulose or a reference diet (RD) substituted with the same amount of corn starch. Water temperature, conductivity and pH were maintained at constant and optimum levels for each species. Animals were fed at 3% of their body weight twice daily and wet body weight was recorded bi-weekly. At the end of experiment, all animals were harvested, measured and midgut gland extracts assayed for alpha-amylase, total protease and cellulase activity levels. After the trial period, redclaw fed with RD showed significantly higher (p<0.05) specific growth rate (SGR) compare with animals fed the TD while SGR of marron and yabby fed the two diets were not significantly different (p<0.05). Cellulase expression levels in redclaw were not significantly different between diets. Marron and yabby showed significantly higher cellulase activity when fed the RD. Amylase and protease activity in all three species were significantly higher in the animals fed with RD (Table 1). These results indicate that test animals of all species can utilize starch better than dietary soluble cellulose in their diet and inclusion of 20% soluble cellulose in diets does not appear to have any significant negative effect on their growth rate but survival was impacted in C. quadricarinatus while not in C. tenuimanus or C. destructor.

Life in the baby boomer library world : a survival guide

According to Australian Job Search, just 14% of librarians are under the age of 35. As a Generation Y librarian, flexibility is a key factor to ensuring survival in the Baby Boomer library and overcoming employment, promotion and in particular stereotype barriers. This paper draws upon generational and library workforce research, coupled with industry experience to provide practical advice and strategies to break through both personal and professional barriers for the Generation Y librarian in the Baby Boomer library world. Industry understanding, drawn from personal experiences of working in public, education and special libraries, utilises my journey as a librarian since graduation in 2005 to discuss barriers faced and methods for breaking through. In my previous position as Teaching and Learning Librarian at Northern Melbourne Institute of TAFE from 35 library staff I was the sole member under 30. In addition I was the youngest member of the Library Management Team by 20 years, providing a perfect example of the Generation Y librarian within a Baby Boomer environment. This experience provides the platform for exploring strategies for understanding and overcoming ageist ideas, generational stereotypes, and employment barriers. Discussion regarding the need to develop sound industry knowledge for survival within the library world will also be raised.

Effects of soluble dietary cellulose on specific growth rate, survival and digestive enzyme activities in three freshwater crayfish (Cherax) species

The current study evaluated the effect of soluble dietary cellulose on growth, survival and digestive enzyme activity in three endemic, Australian freshwater crayfish species (redclaw: Cherax quadricarinatus, marron: C. tenuimanus, yabby: C. destructor). Separate individual feeding trials were conducted for late-stage juveniles from each species in an automated recirculating freshwater, culture system. Animals were fed either a test diet (TD) that contained 20% soluble cellulose or a reference diet (RD) substituted with the same amount of corn starch, over a 12 week period. Redclaw fed with RD showed significantly higher (p<0.05) specific growth rates (SGR) compared with animals fed the TD, while SGR of marron and yabby fed the two diets were not significantly different. Expressed cellulase activity levels in redclaw were not significantly different between diets. Marron and yabby showed significantly higher cellulase activity when fed the RD (p<0.05). Amylase and protease activity in all three species were significantly higher in the animals fed with RD (p<0.05). These results indicate that test animals of all three species appear to utilize starch more efficiently than soluble dietary cellulose in their diet. The inclusion of 20% soluble cellulose in diets did not appear, however, to have a significant negative effect on growth rates.

A data mining driven crash risk profiling method for road asset management

This thesis takes a new data mining approach for analyzing road/crash data by developing models for the whole road network and generating a crash risk profile. Roads with an elevated crash risk due to road surface friction deficit are identified. The regression tree model, predicting road segment crash rate, is applied in a novel deployment coined regression tree extrapolation that produces a skid resistance/crash rate curve. Using extrapolation allows the method to be applied across the network and cope with the high proportion of missing road surface friction values. This risk profiling method can be applied in other domains.

Trauma and survival in African humanitarian entrants to Australia

Former refugees have been resettled in Australia since the 1940’s through the Humanitarian Migration Stream. This chapter highlights the impact of forced migration and the refugee experience of trauma on survival. The journey from pre-migration crises, to the process of fleeing one’s country, through to the challenges associated with resettlement, can have a significant impact on the mental health of Humanitarian Entrants to Australia. Differences in culture can have an impact on the meaning constructed from these experiences, and on help-seeking behaviour and preferred methods of intervention. To date, Western mental health services have used an understanding of trauma based on pathology and largely individualist intervention techniques. In this chapter, however, we seek to understand the experience of trauma for former refugees from a salutogenic perspective, and acknowledge community based coping methods and the strengths and resilience of former refugees. Using the construct of posttraumatic growth, adaptive factors of strength, religion, compassion, and new possibilities are identified as relevant to African Humanitarian Entrants in Australia.