3,561 research outputs found

    Updating predictive accident models of modern rural single carriageway A-roads

    Get PDF
    Reliable predictive accident models (PAMs) are essential to design and maintain safe road networks and yet the models most commonly used in the UK were derived using data collected 20 to 30 years ago. Given that the national personal injury accident total fell by some 30% in the last 25 years, while road traffic increased by over 60%, significant errors in scheme appraisal and evaluation based on the models currently in use seem inevitable. In this paper the temporal transferability of PAMs for modern rural single carriageway A-roads is investigated and their predictive performance is evaluated against a recent data set. Despite the age of these models, the PAMs for predicting the total accidents provide a remarkably good fit to recent data and these are more accurate than models where accidents are disaggregated by type. The performance of the models can be improved by calibrating them against recent data

    A study of omega bands and Ps6 pulsations on the ground, at low altitude and at geostationary orbit

    Get PDF
    We investigate the electrodynamic coupling between auroral omega bands and the inner magnetosphere. The goal of this study is to determine the features to which omega bands map in the magnetosphere. To establish the auroral-magnetosphere connection, we appeal to the case study analysis of the data rich event of September 26, 1989. At 6 magnetic local time (MLT), two trains of Ps6 pulsations (ground magnetic signatures of omega bands) were observed to drift over the Canadian Auroral Network For the OPEN Program Unified Study (CANOPUS) chain. At the same time periodic ionospheric flow patterns moved through the collocated Bistatic Auroral Radar System (BARS) field of view. Similar coincident magnetic variations were observed by GOES 6, GOES 7 and SCATHA, all of which had magnetic foot points near the CANOPUS/BARS stations. SCATHA, which was located at 6 MLT, 0.5 RE earthward of GOES 7 observed the 10 min period pulsations, whereas GOES 7 did not. In addition, DMSP F6 and F8 were over-flying the region and observed characteristic precipitation and flow signatures. From this fortunate constellation of ground and space observations, we conclude that auroral omega bands are the electrodynamic signature of a corrugated current sheet (or some similar spatially localized magnetic structure) in the near-Earth geostationary magnetosphere

    Use of Photovoice to engage stakeholders in planning for patient-centered outcomes research

    Get PDF
    Background Research is needed to inform patient and provider decisions about how to best care for patients who go to the emergency department with complaints of chest pain when their symptoms are due to anxiety rather than a heart problem. However, this research may not be a high priority due, in part, to a lack of awareness for the severity of anxiety symptoms and the impact of anxiety on peoples’ daily lives. In this commentary article, we highlight the use of Photovoice as a unique method to share patients’ lived experience of anxiety with providers, researchers, and health system leaders. Main text A brief background on Photovoice methods, the process of patient partner involvement in Photovoice, and the project’s Photovoice results (posters, photos and captions) is presented. Conclusion Photovoice achieved its intended effects of increasing awareness of all stakeholders about the burden of anxiety in patients’ lives and the imperative of improving emergency department care for anxiety. This resulted in increased participation in a multi-stakeholder research partnership, critical health system support that included costs to the health system associated with implementing interventions to be tested, and submission of a patient-centered outcomes research proposal that is currently under review. In addition, Photovoice had positive benefits for participants including a therapeutic effect, may have increased group cohesion, and empowerment of patients as partners in the research process

    Evidence for a colour dependence in the size distribution of main belt asteroids

    Get PDF
    We present the results of a project to detect small (~1 km) main-belt asteroids with the 3.6 meter Canada-France-Hawaii Telescope (CFHT). We observed in 2 filters (MegaPrime g' and r') in order to compare the results in each band. Owing to the observational cadence we did not observe the same asteroids through each filter and thus do not have true colour information. However strong differences in the size distributions as seen in the two filters point to a colour-dependence at these sizes, perhaps to be expected in this regime where asteroid cohesiveness begins to be dominated by physical strength and composition rather than by gravity. The best fit slopes of the cumulative size distributions (CSDs) in both filters tend towards lower values for smaller asteroids, consistent with the results of previous studies. In addition to this trend, the size distributions seen in the two filters are distinctly different, with steeper slopes in r' than in g'. Breaking our sample up according to semimajor axis, the difference between the filters in the inner belt is found to be somewhat less pronounced than in the middle and outer belt, but the CSD of those asteroids seen in the r' filter is consistently and significantly steeper than in g' throughout. The CSD slopes also show variations with semimajor axis within a given filter, particularly in r'. We conclude that the size distribution of main belt asteroids is likely to be colour dependent at kilometer sizes and that this dependence may vary across the belt.Comment: 28 pages, 5 figures, submitted to the Astronomical Journa

    The radio luminosity distribution of pulsars in 47 Tucanae

    Full text link
    We have used the Australia Telescope Compact Array to seek the integrated radio flux from all the pulsars in the core of the globular cluster 47 Tucanae. We have detected an extended region of radio emission and have calibrated its flux against the flux distribution of the known pulsars in the cluster. We find the total 20-cm radio flux from the cluster's pulsars to be S = 2.0 +/- 0.3 mJy. This implies the lower limit to the radio luminosity distribution to be L_1400 = 0.4 mJy kpc^2 and the size of the observable pulsar population to be N < 30.Comment: 7 pages, 4 figures, MNRAS in pres

    Neutron induced background in the COMPTEL detector on the Gamma Ray Observatory

    Get PDF
    Interactions of neutrons in a prototype of the Compton imaging telescope (COMPTEL) gamma ray detector for the Gamma Ray Observatory were studied to determine COMPTEL's sensitivity as a neutron telescope and to estimate the gamma ray background resulting from neutron interactions. The IUCF provided a pulsed neutron beam at five different energies between 18 and 120 MeV. These measurements showed that the gamma ray background from neutron interactions is greater than previously expected. It was thought that most such events would be due to interactions in the upper detector modules of COMPTEL and could be distinguished by pulse shape discrimination. Rather, the bulk of the gamma ray background appears to be due to interactions in passive material, primarily aluminum, surrounding the D1 modules. In a considerable fraction of these interactions, two or more gamma rays are produced simultaneously, with one interacting in the D1 module and the other interacting in the module of the lower (D2) detector. If the neutron interacts near the D1 module, the D1 D2 time of flight cannot distinguish such an event from a true gamma ray event. In order to assess the significance of this background, the flux of neutrons in orbit has been estimated based on observed events with neutron pulse shape signature in D1. The strength of this neutron induced background is estimated. This is compared with the rate expected from the isotropic cosmic gamma ray flux

    A call to action: MTHFR polymorphisms should not be a part of inherited thrombophilia testing

    Full text link
    Testing for polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene is still a standard part of thrombophilia testing in many laboratories. However, it is clear that these polymorphisms are not risk factors for arterial or venous thrombosis and therefore should not be part of thrombophilia testing. Eliminating MTHFR from thrombophilia testing will reduce patient concerns and health care costs

    Preparing Extension Professionals: The Ohio State University\u27s Model of Extension Education

    Get PDF
    Extension systems throughout the United States require individuals to have college degrees to work as Extension professionals. This article shares The Ohio State University\u27s approach to Extension Education in the Department of Human and Community Resource Development. A model is presented for preparing Extension professionals in an academic setting. Based on the research literature, competencies for success in Extension are matched with courses at the undergraduate and graduate levels of instruction. By sharing our approach, we hope to encourage dialogue and discussion that will help us and other academic programs to offer the best possible curriculum for preparing Extension educators
    corecore