Travel time competitiveness of cycling in Sydney

A key issue for both sustainable transport and public health is the viability of cycling as a genuine alternative to the car, particularly for short trips. This paper considers this issue by assessing hypothetically the travel time implications of substituting actual car trips with cycling. The car trips are captured over several weeks for 178 Sydney motorists using GPS technology, while the cycling trips are generated using reverse geocoding processes in GIS software, taking into account the impacts of terrain in particular on cycling travel times. Both individual trips and more importantly trip chains are considered. Assuming an ‘inexperienced adult’ cyclist, results suggest that over 90 percent of car trips up to five kilometres in length (which comprise 58 percent of trips), could be cycled within 10 minutes of the time taken by car, a similar finding to results reported elsewhere. As the level of cycling experience increases, the ‘bikeable’ distance increases with the majority of ‘commuter adults’ being able to cycle the median commuting distance in Sydney of 11 kilometres with little additional travel time compared to a car. When considering trip chains, while the competitiveness of cycling goes down as more legs are included, the total distance of the chain emerges as a more crucial issue with cycling being equally competitive for trip chains shorter than 10 kilometres as for individual trips shorter than 10 kilometres. Finally, when considered in the context of daily travel time budgets, the analysis suggests around 20 percent of people could switch totally from cars to bicycles without incurring more than a 20 minute additional increase in travel time on average per day

Electronic ticketing systems as a mechanism for travel behaviour change? Evidence from Sydney’s Opal Card

Smartcard and other forms of electronic ticketing have become integral to modern public transport systems. While aggregate ridership figures have generally been positive, little is known about the drivers behind these changes because of a lack of travel information on individuals before and after implementation of such systems. This working paper presents analysis from a naturalistic travel behaviour study of inner-city Sydney residents that coincided with the phased introduction of the Opal smartcard system. Using a differences-in-differences methodology, results indicate significant reductions in car use of around 10 minutes/day with commensurate increases in train use and incidental walking. This trend holds across income groups and is more pronounced for older residents. Results add further weight to the merits of simplifying ticket purchasing as part of a package of policy measures designed to increase public transport usage

Development of an online diary for longitudinal travel / activity surveys

Motivated by the continued search for methods to reduce participant burden and non-response, and improve the quality of travel data, this paper details the development of a new online travel/activity diary to support a major longitudinal investigation of travel in Sydney, Australia. The diary employs several innovative features designed to simplify the process of data entry, and improve participant recall and completeness of travel, including auto-fills, prompts, trip editing capabilities, favourite trips and a dragand- drop technique for capturing travel mode. An additional innovation is the ability to view a GPS-based Google map of daily travel while completing the diary to assist with recall. The diary is tested on 37 participants, with a range of diagnostics provided to assess their comprehension and interaction with the diary, reaction and burden, and completeness of data provided. Overall, 89% of participants complete all seven days of the diary with 75% indicating no issues once they become accustomed to how it works. Trip entry times average around two minutes/trip with three-quarters of trips entered within 24 hours of being made and 96% of trips provided with complete details. In terms of the GPS component, while the data itself is of variable quality and the optional viewing of trips is lower than anticipated, those carrying a GPS report more trips/day and segments/day, fewer missing days, and provide more complete trip data

Dynamic responses of freight operators to government policies: a latent curve modelling approach

Using a unique dataset collected from Australian (urban) freight operators using an adaptive-dynamic simulation method, firms’ dynamic responses are modelled using latent curve models to investigate firms’ adaptation strategies in response to new government policies. Latent curve models are used to identify the magnitude and timing of the responses as well as what factors influence the changes. The results show that firms adapt gradually to the policies with some decisions changing quicker than others. Furthermore, the drivers of responses changes during the adaptation process and that not all incremental decisions are made solely on the basis of cost

Commodity interaction in Freight movement models for Greater Sydney

Central to freight movement models is an understanding of where the freight commodities are produced and consumed. An important driver in the production and/or consumption of each commodity is the production and consumption of other commodities. In this paper, these important interactions between commodities are captured in a path based freight model which incorporates models of commodity production and consumption. We identify the key factors driving the consumption and production of each commodity together with their elasticities. To be suitable for forecasting and policy testing, the estimated models are transformed into linked logit models that allow for important policy measures such as accessibility and commodity generation powers to be estimated. The proposed model has been implemented to generate the amount of commodity of each type produced and consumed in each state of Australia with illustrations of how the production and/or consumption of one commodity triggers the production and/or consumption of others commodities. When built into an integrated transport and land use model system, this capability adds a richness to the way in which freight movements influence and hence impact on the performance of the entire transport network, for both passenger and freight

Collecting longitudinal data from freight operators: survey design and implementation

Freight transport research has generally been limited by a lack of data of the breadth and quality available for passenger transport, particularly in terms of behavioural data. Although there are a number of reasons for this lack of data, the challenges of collecting freight data including the expense, participant burden and confidentiality issues are amongst the most significant. Although some improvements in technology and survey design have allowed for the collection of more behavioural freight data more improvements would be beneficial. This paper discusses the survey design and implementation of a survey intended to collect longitudinal behavioural data on the responses of freight transport firms to the introduction of environmental policies. The design of the survey is centred around a hypothetical scenario where respondents are asked how they would complete a given freight task within common constraints including time windows and delivery requirements. One of the key components of the survey design is a dynamic component that is intended to simulate the changing business environment to which firms are required to adapt. This paper also looks at the participant burden involved in completing the survey and compares how this differs depending on how respondents completed the survey

PON1 status does not influence cholinesterase activity in Egyptian agricultural workers exposed to chlorpyrifos.

Animal studies have shown that paraoxonase 1 (PON1) genotype can influence susceptibility to the organophosphorus pesticide chlorpyrifos (CPF). However, Monte Carlo analysis suggests that PON1 genotype may not affect CPF-related toxicity at low exposure conditions in humans. The current study sought to determine the influence of PON1 genotype on the activity of blood cholinesterase as well as the effect of CPF exposure on serum PON1 in workers occupationally exposed to CPF. Saliva, blood and urine were collected from agricultural workers (n=120) from Egypt's Menoufia Governorate to determine PON1 genotype, blood cholinesterase activity, serum PON1 activity towards chlorpyrifos-oxon (CPOase) and paraoxon (POase), and urinary levels of the CPF metabolite 3,5,6-trichloro-2-pyridinol (TCPy). The PON1 55 (P≤0.05) but not the PON1 192 genotype had a significant effect on CPOase activity. However, both the PON1 55 (P≤0.05) and PON1 192 (P≤0.001) genotypes had a significant effect on POase activity. Workers had significantly inhibited AChE and BuChE after CPF application; however, neither CPOase activity nor POase activity was associated with ChE depression when adjusted for CPF exposure (as determined by urinary TCPy levels) and stratified by PON1 genotype. CPOase and POase activity were also generally unaffected by CPF exposure although there were alterations in activity within specific genotype groups. Together, these results suggest that workers retained the capacity to detoxify chlorpyrifos-oxon under the exposure conditions experienced by this study population regardless of PON1 genotype and activity and that effects of CPF exposure on PON1 activity are minimal

A Broadband Study of the Emission from the Composite Supernova Remnant MSH 11-62

MSH 11-62 (G291.1-0.9) is a composite supernova remnant for which radio and X-ray observations have identified the remnant shell as well as its central pulsar wind nebula. The observations suggest a relatively young system expanding into a low density region. Here we present a study of MSH 11-62 using observations with the Chandra, XMM-Newton, and Fermi observatories, along with radio observations from the Australia Telescope Compact Array (ATCA). We identify a compact X-ray source that appears to be the putative pulsar that powers the nebula, and show that the X-ray spectrum of the nebula bears the signature of synchrotron losses as particles diffuse into the outer nebula. Using data from the Fermi LAT, we identify gamma-ray emission originating from MSH 11-62. With density constraints from the new X-ray measurements of the remnant, we model the evolution of the composite system in order to constrain the properties of the underlying pulsar and the origin of the gamma-ray emission.Comment: 12 Pages, 12 figures. Accepted for publication in the Astrophysical Journa

Ebola Virus Persistence in Semen of Male Survivors

We investigated the duration of Ebola virus (EBOV) RNA and infectious EBOV in semen specimens of 5 Ebola virus disease (EVD) survivors. EBOV RNA and infectious EBOV was detected by real-time RT-PCR and virus culture out to 290 days and 70 days, respectively, after EVD onset