Investigating pedestrian injury crashes on modern roundabouts in Addis Ababa, Ethiopia

Pedestrian crashes are one of the major road safety problems in developing countries representing about 40% of total fatal crashes in low income countries. Despite the fact that many pedestrian crashes in these countries occur at unsignalized intersections such as roundabouts, studies focussing on this issue are limited—thus representing a critical research gap. The objective of this study is to develop safety performance functions for pedestrian crashes at modern roundabouts to identify significant roadway geometric, traffic and land use characteristics related to pedestrian safety. To establish the relationship between pedestrian crashes and various causal factors, detailed data including various forms of exposure, geometric and traffic characteristics, and spatial factors such as proximity to schools and proximity to drinking establishments were collected from a sample of 22 modern roundabouts in Addis Ababa, Ethiopia, representing about 56% of such roundabouts in Addis Ababa. To account for spatial correlation resulting from multiple observations at a roundabout, both the random effect Poisson (REP) and random effect Negative Binomial (RENB) regression models were estimated and compared. Model goodness of fit statistics reveal a marginally superior fit of the REP model compared to the RENB model of pedestrian crashes at roundabouts. Pedestrian crossing volume and the product of traffic volumes along major and minor road had significant and positive associations with pedestrian crashes at roundabouts. The presence of a public transport (bus/taxi) terminal beside a roundabout is associated with increased pedestrian crashes. While the maximum gradient of an approach road is negatively associated with pedestrian safety, the provision of a raised median along an approach appears to increase pedestrian safety at roundabouts. Remedial measures are identified for combating pedestrian safety problems at roundabouts in the context of a developing country.

Crossing lines: Sport history, transformative narratives, and Aboriginal Australia

In this collaborative article, we seek to unsettle the dominance of Western, reconstructionist accounts of Indigenous Australian sport history through reflections on our past research in the Queensland Aboriginal community of Cherbourg. That research focussed on a statue of legendary 1930s cricketer, Eddie Gilbert, and on sport exhibitions in Cherbourg's Ration Shed Museum. Here, we are less concerned with unveiling the ‘true’ account of Australian Aboriginal sporting history, or even a ‘true’ Indigenous representation of events. Rather, we are interested in analysing various perspectives in order to generate a more inclusive and complete account of Aboriginal sport history and the narrative implications of these for Indigenous and non-Indigenous Australia. Central to this endeavour is the positioning of Indigenous knowledge and understanding at the centre of history-making. The article is in two sections: reflections on our past work from the perspectives of the researchers themselves and an Aboriginal academic colleague, followed by a discussion of how those experiences and reflections will inform our pending project on the 1950s and 1960s Cherbourg marching girls teams.

Versatile single-layer sodium phosphidostannate(II): Strain-tunable electronic structure, excellent mechanical flexibility, and an ideal gap for photovoltaics

Density functional theory (DFT) calculations were performed to study the structural, mechanical, electrical, optical properties, and strain effects in single-layer sodium phosphidostannate(II) (NaSnP). We find the exfoliation of single-layer NaSnP from bulk form is highly feasible because the cleavage energy is comparable to graphite and MoS2. In addition, the breaking strain of the NaSnP monolayer is comparable to other widely studied 2D materials, indicating excellent mechanical flexibility of 2D NaSnP. Using the hybrid functional method, the calculated band gap of single-layer NaSnP is close to the ideal band gap of solar cell materials (1.5 eV), demonstrating great potential in future photovoltaic application. Furthermore, strain effect study shows that a moderate compression (2%) can trigger indirect-to-direct gap transition, which would enhance the ability of light absorption for the NaSnP monolayer. With sufficient compression (8%), the single-layer NaSnP can be tuned from semiconductor to metal, suggesting great applications in nanoelectronic devices based on strain engineering techniques.

Identifying and forecasting the reverse salient in video game consoles: A performance gap ratio comparative analysis

This study uses the reverse salient methodology to contrast subsystems in video game consoles in order to discover, characterize, and forecast the most significant technology gap. We build on the current methodologies (Performance Gap and Time Gap) for measuring the magnitude of Reverse Salience, by showing the effectiveness of Performance Gap Ratio (PGR). The three subject subsystems in this analysis are the CPU Score, GPU core frequency, and video memory bandwidth. CPU Score is a metric developed for this project, which is the product of the core frequency, number of parallel cores, and instruction size. We measure the Performance Gap of each subsystem against concurrently available PC hardware on the market. Using PGR, we normalize the evolution of these technologies for comparative analysis. The results indicate that while CPU performance has historically been the Reverse Salient, video memory bandwidth has taken over as the quickest growing technology gap in the current generation. Finally, we create a technology forecasting model that shows how much the video RAM bandwidth gap will grow through 2019 should the current trend continue. This analysis can assist console developers in assigning resources to the next generation of platforms, which will ultimately result in longer hardware life cycles.

Dynamics of reverse salience as technological performance gap: An empirical study of the personal computer technology system

The evolution of technological systems is hindered by systemic components, referred to as reverse salients, which fail to deliver the necessary level of technological performance thereby inhibiting the performance delivery of the system as a whole. This paper develops a performance gap measure of reverse salience and applies this measurement in the study of the PC (personal computer) technological system, focusing on the evolutions of firstly the CPU (central processing unit) and PC game sub-systems, and secondly the GPU (graphics processing unit) and PC game sub-systems. The measurement of the temporal behavior of reverse salience indicates that the PC game sub-system is the reverse salient, continuously trailing behind the technological performance of the CPU and GPU sub-systems from 1996 through 2006. The technological performance of the PC game sub-system as a reverse salient trails that of the CPU sub-system by up to 2300 MHz with a gradually decreasing performance disparity in recent years. In contrast, the dynamics of the PC game sub-system as a reverse salient trails the GPU sub-system with an ever increasing performance gap throughout the timeframe of analysis. In addition, we further discuss the research and managerial implications of our findings.

Direct observations of pedestrian unsafe crossing at urban Australian level crossings

The number of pedestrian victims at Australian and foreign level crossings has remained stable over the past decade and it continues to be a significant problem. To examine the factors contributing to pedestrians’ unsafe crossing behaviours, direct observations were conducted at three black spot urban level crossings in Brisbane for a total of 45 h during morning and afternoon peak. In total, 129 pedestrians transgressed the active controls. More transgressions were observed at the crossings located in more populated suburbs in close proximity to large shopping centres and school zones, whereas the smallest number of transgressions were observed at the least populated locations. In addition to characteristics associated with the larger socio-economic area, the patterns of transgression could be associated with the properties of the existing safety equipment and the design of each level crossing (i.e. location of the platforms, number of rail tracks). Indeed, the largest number of crossed unoccupied but “at risk” rail tracks (where a train could have passed), was observed at the crossing with the least transgressions. Contrary to previous findings, younger adults were the most frequent transgressors. School children and elderly were most likely to transgress in groups. Potential directions for future research and more effective measures are discussed.

Boundary crossing: A theoretical framework to understand the operation dynamics of industry-school partnerships

Industry-school partnerships (ISPs) are increasingly being recognised as a new way of providing vocational education opportunities. However, there is limited research investigating their impact on systemic (organisational and structural) and human resource (teachers and education managers) capacity to support school to work transitions. This paper reports on a government led ISP, established by the Queensland state government. ISPs across three industry sectors: minerals and energy; building and construction; and aviation are included in this study. This research adopted a qualitative case study methodology and draws upon boundary crossing theory to understand the dynamics of how each industry sector responded to systemic and human resource issues that emerged in each ISP. The main finding being that the systematic application of boundary crossing mechanisms by all partners pro-duced mutually beneficial outcomes. ISPs from the three sectors adopted different models, leveraged different boundary crossing objects but all maintained the joint vision and mutually agreed outcomes. All three ISPs genuinely crossed boundaries, albeit in different ways, and assisted teachers to co-pro-duce industry-based curriculums, share sector specific knowledge and skills that help enhance the school to work transition for school graduates.

'Crossing the line': Criminological expertise, policy advice and the 'quarrelling society'

In October 2009, Professor David Nutt, eminent neuropsychopharmacologist and world leading expert on drugs, was dismissed as Chair of the UK government’s Advisory Council on the Misuse of Drugs for comments he made at the Centre for Crime and Justice Studies’ Eve Saville lecture. This article considers the role of evidence in political decision-making through the case of David Nutt. It is argued that the status of expert knowledge is in crisis for both the natural and the social sciences. We examine the role of the criminological advisor within emerging discourses of public criminology and suggest that high-stakes political issues can open up unprecedented opportunities for critical voices to engage in unbridled critique and to mobilise movements of dissent.

The 'gender gap' in authorship in nursing literature

OBJECTIVES: Gender bias has been found in medical literature, with more men than women as first or senior authors of papers, despite about half of doctors being women. Nursing is about 90% female, so we aimed to determine if similar biases exist in nursing literature. DESIGN: Taking the eight non-specialist nursing journals with the highest impact factors for that profession, we counted the numbers of men and women first authors over 30 years. SETTING: We used nursing journals from around the world which attract the highest impact factors for nursing publication. PARTICIPANTS: Eight journals qualified for entry, three from the United Kingdom, four from the United States of America, and one from Australia. MAIN OUTCOME MEASURES Using Chi-square and Fisher exact tests, we determined differences between the numbers of men and women across all the journals, between countries (USA, UK and Australia), changes over the 30 years, and changes within journals over time. RESULTS Despite the small proportion of men in the nursing workforce, up to 30% of first authors were men. UK journals were more likely to have male authors than USA journals, and this increased over time. USA journals had proportions of male first authors consistent with the male proportion of its nursing workforce. CONCLUSIONS In the UK (though not in the USA) gender bias in nursing publishing exists, even though the nursing workforce is strongly feminized. This warrants further research, but is likely to be due to the same reasons for the gender gap in medical publishing; that is, female nurses take time out to have families, and social and family responsibilities prevent them taking opportunities for career progression, whereas men's careers often are not affected in such ways.

VFT performance of a 180/110 mm co-axial gap in SF6 up to 4 bar absolute

Disconnector switch operation in GIS generates VFT voltages in the system. It is important, for insulation co-ordination purposes, to obtain accurate VFT V-t data for typical gap geometries found in GIS. This paper presents experimentally obtained VFT V-t data for a 180/1 lOmm co-axial gap. The VFT has a time to first peak of 35 ns and a oscillation frequency of 13,6 MHz. Due to the location of the voltage divider in a compartment adjacent to the gap, a correction factor of 1.1 is used to relate the measured breakdown voltage to that in the gap. Positive polarity VFT V-t data is presented for 1, 2, 3 and 4 bar absolute and negative polarity VFT data for 3 and 4 bar absolute. Two methods of generating the VFT's are used. The first is to power up the test transformer at power frequency. The second is to generate a switching impulse by discharging a capacitor into the primary of the test transformer.

Somewhere between haste and delay... Investigating the interactions of road users and pedestrians in a dynamic rail level crossing environment

There are currently 23,500 level crossings in Australia, broadly divided into one of two categories: active level crossings which are fully automatic and have boom barriers, alarm bells, flashing lights, and pedestrian gates; and passive level crossings, which are not automatic and aim to control road and pedestrianised walkways solely with stop and give way signs. Active level crossings are considered to be the gold standard for transport ergonomics when grade separation (i.e. constructing an over- or underpass) is not viable. In Australia, the current strategy is to annually upgrade passive level crossings with active controls but active crossings are also associated with traffic congestion, largely as a result of extended closure times. The percentage of time level crossings are closed to road vehicles during peak periods increases with the rise in the frequency of train services. The popular perception appears to be that once a level crossing is upgraded, one is free to wipe their hands and consider the job done. However, there may also be environments where active protection is not enough, but where the setting may not justify the capital costs of grade separation. Indeed, the associated congestion and traffic delay could compromise safety by contributing to the risk taking behaviour by motorists and pedestrians. In these environments it is important to understand what human factor issues are present and ask the question of whether a one size fits all solution is indeed the most ergonomically sound solution for today’s transport needs.

Group 14 element-based non-centrosymmetric quantum spin hall insulators with large bulk gap

To date, a number of two-dimensional (2D) topological insulators (TIs) have been realized in Group 14 elemental honeycomb lattices, but all are inversionsymmetric. Here, based on first-principles calculations, we predict a new family of 2D inversion-asymmetric TIs with sizeable bulk gaps from 105 meV to 284 meV, in X2–GeSn (X = H, F, Cl, Br, I) monolayers, making them in principle suitable for room-temperature applications. The nontrivial topological characteristics of inverted band orders are identified in pristine X2–GeSn with X = (F, Cl, Br, I), whereas H2–GeSn undergoes a nontrivial band inversion at 8% lattice expansion. Topologically protected edge states are identified in X2–GeSn with X = (F, Cl, Br, I), as well as in strained H2–GeSn. More importantly, the edges of these systems, which exhibit single-Dirac-cone characteristics located exactly in the middle of their bulk band gaps, are ideal for dissipationless transport. Thus, Group 14 elemental honeycomb lattices provide a fascinating playground for the manipulation of quantum states.

Mind the Gap!: Fundraisers and their nonprofit organisational leaders do think differently and this difference matters

Australian fundraisers and their organisational leaders (CEOs and board members) diverge sometimes in how they think about fundraising. In fact, eight key differences emerged in the recent Australian study that sparked this paper. A strong fundraising/leadership accord in attitudes toward fundraising would seem to be important, especially in tightened funding regimes. Both demand and competition for funding beyond the government dollar is growing. Many organisations are moving into community fundraising for the first time due to imperilled government funding. The sophistication of all donation sources is likewise on the rise. These factors add complexity to the fundraising role and to the task of boards and CEOs in managing fundraising strategy and activity. Some variances in professional outlook might be predictable between fundraisers and fundraising organisation leaders. However, the differences found in our study are in areas that potentially affect the organisation’s ability to fill its mission. It is advisable then to ‘mind the gap’ and also to explore it.

Energy gap in the aetiology of body weight gain and obesity: A challenging concept with a complex evaluation and pitfalls

The concept of energy gap(s) is useful for understanding the consequence of a small daily, weekly, or monthly positive energy balance and the inconspicuous shift in weight gain ultimately leading to overweight and obesity. Energy gap is a dynamic concept: an initial positive energy gap incurred via an increase in energy intake (or a decrease in physical activity) is not constant, may fade out with time if the initial conditions are maintained, and depends on the 'efficiency' with which the readjustment of the energy imbalance gap occurs with time. The metabolic response to an energy imbalance gap and the magnitude of the energy gap(s) can be estimated by at least two methods, i.e. i) assessment by longitudinal overfeeding studies, imposing (by design) an initial positive energy imbalance gap; ii) retrospective assessment based on epidemiological surveys, whereby the accumulated endogenous energy storage per unit of time is calculated from the change in body weight and body composition. In order to illustrate the difficulty of accurately assessing an energy gap we have used, as an illustrative example, a recent epidemiological study which tracked changes in total energy intake (estimated by gross food availability) and body weight over 3 decades in the US, combined with total energy expenditure prediction from body weight using doubly labelled water data. At the population level, the study attempted to assess the cause of the energy gap purported to be entirely due to increased food intake. Based on an estimate of change in energy intake judged to be more reliable (i.e. in the same study population) and together with calculations of simple energetic indices, our analysis suggests that conclusions about the fundamental causes of obesity development in a population (excess intake vs. low physical activity or both) is clouded by a high level of uncertainty.

Optimizing the quantum dot: Plasmon interaction in a nano gap waveguide

Spontaneous emission (SE) of a Quantum emitter depends mainly on the transmission strength between the upper and lower energy levels as well as the Local Density of States (LDOS)[1]. When a QD is placed in near a plasmon waveguide, LDOS of the QD is increased due to addition of the non-radiative decay and a plasmonic decay channel to free space emission[2-4]. The slow velocity and dramatic concentration of the electric field of the plasmon can capture majority of the SE into guided plasmon mode (Гpl ). This paper focused on studying the effect of waveguide height on the efficiency of coupling QD decay into plasmon mode using a numerical model based on finite elemental method (FEM). Symmetric gap waveguide considered in this paper support single mode and QD as a dipole emitter. 2D simulation models are done to find normalized Гpl and 3D models are used to find probability of SE decaying into plasmon mode ( β) including all three decay channels. It is found out that changing gap height can increase QD-plasmon coupling, by up to a factor of 5 and optimally placed QD up to a factor of 8. To make the paper more realistic we briefly studied the effect of sharpness of the waveguide edge on SE emission into guided plasmon mode. Preliminary nano gap waveguide fabrication and testing are already underway. Authors expect to compare the theoretical results with experimental outcomes in the future