On the fine structure of medium energy electron fluxes in the auroral zone and related effects in the ionospheric D-region

This study is based on measurements of trapped and precipitated electrons of energy &gt;30 keV and &gt;100 keV observed by polar orbiting environmental satellites during overpasses of the imaging riometer at Kilpisjärvi, Finland. The satellites are in sun-synchronous orbits of about 850 km altitude, recording the electron fluxes at 2-s time resolution. The riometer measures the radiowave absorption at 38.2 MHz, showing the spatial pattern within a 240 km field of view. <br><br> The analysis has focussed on two areas. Having found a close correlation between the radiowave absorption and the medium-energy electron fluxes during satellite overpasses, empirical relationships are derived, enabling one quantity to be predicted from the other for three sectors of local time. It is shown that small-scale variations observed during a pass are essentially spatial rather than temporal. <br><br> Other properties, such as the spectra and the relation between precipitated and trapped components, are also considered in the light of the theory of pitch angle scattering by VLF waves. It is found that the properties and behaviour depend strongly on the time of day. In the noon sector, the precipitated and trapped fluxes are highly correlated through a square law relationship

The estimation of D-region electron densities from riometer data

International audienceAt high latitude the hard electron precipitation associated with auroral activity is a major source of ionization for the D-region, one consequence being the absorption of radio waves. Direct measurements of the D-region electron density are not readily available, however. This paper investigates the relationship between the electron density at altitudes between 100 and 70 km and the total radio absorption observed with a riometer, with a view to using the latter to predict the former. Tables are given of the median electron density corresponding to 1 dB absorption at 27.6 MHz for each hour of the day, and it is shown that at certain heights the estimates will be accurate to within a factor of 1.6 on 50% of the occasions. A systematic variation with time of day is probably associated with a progressive hardening of the typical electron spectrum during the morning hours. There is also evidence for a seasonal effect possibly due to seasonal variations of the mesosphere

Mobilising communities to address alcohol harm : an Alcohol Health Champion approach

In this article, Cathy Ure et al. look at engaging communities in order to reduce alcohol harms. By training Alcohol Health Champions, individuals can support vulnerable friends and family, and work within their communities to influence policy and promote change

Workplace-based learning for undergraduate and pre-registration healthcare professionals: A systematic map of the UK research literature 2003-2013

What do we want to know? What is the nature of the research on workplace-based learning for undergraduate and pre-registration healthcare professionals in the UK? How many studies are there and what do they focus on? Who wants to know? The map was funded by the Higher Education Academy, UCL Institute of Education, University College London, and the Association for the Study of Medical Education. Workplace based learning is a key component of healthcare professionals education and training and is therefore a key concern of educators, professional bodies, professional regulators, the NHS and Health Education England. What did we find? We identified 117 UK studies about workplace-based learning for undergraduate/pre-registration healthcare students published between 2003 and 2013. The majority of studies (n = 111) focused on students views or experiences of workplace-based learning. Very few studies (n= 6) investigated the impacts of workplace-based learning (using quantitative measurements of change in student attitudes, knowledge or skill). There were no studies that measured impacts on organisational practice or patient/client outcomes. The highest number of studies focused on nursing students in workplace- based learning (n = 52) and there were relatively fewer studies examining students in medicine (n = 13), dentistry (n = 11) and midwifery (n = 10). Studies of workplace-based learning for students of the allied health professions were also limited in number (e.g. four physiotherapy studies). Eighteen studies focused on workplace-based learning in an inter-professional context. The majority of studies used qualitative data collected using questionnaires and interviews. What are the conclusions? This is the first report, to our knowledge, that systematically identifies and characterises empirical research literature from the UK on workplace-based learning for undergraduate and pre-registration students across multiple healthcare professions and settings. Based on the findings above, strategies for future research should include: Further research in the field of workplace-based learning for undergraduate and pre-registration healthcare professionals; More research that can measure the impact of workplace-based learning (using quantitative, independent outcome measures); In-depth systematic reviews of student or educator views of workplace-based learning in the healthcare professions; More research on workplace-based learning for healthcare professions other than nursing. How did we get these results? This project undertook a rapid systematic map. This approach employs systematic and transparent methods to describe the research field. The map included two main stages: A focused search and screening process to identify relevant literature. Two electronic databases and a selection of websites were searched for studies. A set of inclusion/exclusion criteria were developed in collaboration with the advisory group and used to screen potentially relevant reports. Descriptive narrative mapping of a subset of the relevant studies. A coding tool was developed and applied to all UK studies. This described key elements of the research: the healthcare students participating in the study, the nature of the workplace-based learning, the study methods and the type of findings. As in other systematic maps the actual research findings of individual studies are not reported

Improved Searches for HI in Three Dwarf Spheroidal Galaxies

Previous searches for HI in our Galaxy's dwarf spheroidal companions have not been complete enough to settle the question of whether or not these galaxies have HI, especially in their outer parts. We present VLA observations of three dwarf spheroidals: Fornax, Leo II, and Draco, all of which have known stellar velocities. The new data show no HI emission or absorption. Column density limits in emission are 4--7 x 10^18 atoms/cm^2 in the centers of the galaxies. The importance of the new observations is that they cover larger areas than previous searches and they are less plagued by confusion with foreground (Galactic) HI. The apparent absence of neutral gas in the Fornax dwarf spheroidal is especially puzzling because recent photometry shows evidence of stars only 10^8 years old. We discuss whether the VLA observations could have missed significant amounts of HI.Comment: 20 pages, 7 figures; to appear in the Astronomical Journa

Forecasting how residential urban form affects the regional carbon savings and costs of retrofitting and decentralized energy supply

Low carbon energy supply technologies are increasingly used at the building and community scale and are an important part of the government decarbonisation strategy. However, with their present state of development and costs, many of these decentralised technologies rely on public subsidies to be financially viable. It is questionable whether they are cost effective compared to other ways of reducing carbon emissions, such as decarbonisation of conventional supply and improving the energy efficiency of dwellings. Previous studies have found it difficult to reliably estimate the future potential of decentralised supply because this depends on the available residential space which varies greatly within a city region. To address this problem, we used an integrated modelling framework that converted the residential density forecasts of a regional model into a representation of the building dimensions and land of the future housing stock. This included a method of estimating the variability of the dwellings and residential land. We present the findings of a case study of the wider south east regions of England that forecasted the impacts of energy efficiency and decentralised supply scenarios to year 2031. Our novel and innovative method substantially improves the spatial estimates of energy consumption compared to building energy models that only use standard dwelling typologies. We tested the impact of an alternative spatial planning policy on the future potential of decentralised energy supply and showed how lower density development would be more suitable for ground source heat pumps. Our findings are important because this method would help to improve the evidence base for strategies on achieving carbon budgets by taking into account how future residential space constraints would affect the suitability and uptakes of these technologies.The research was funded by the UK Engineering and Physical Sciences Research Council (EPSRC) as part of the ReVISIONS Research Grant (EP/F007566/1) and Liveable Cities Programme Grant (EP/J017698). The LUTI model was developed with financial support from the East of England Development Agency for the ReVISIONS project. Ordnance Survey provided MasterMap™ for academic use.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.apenergy.2016.02.09

Validation of Computational Models of Auxiliary Ventilation Systems with Experimental Data

This paper reports the interim findings of a research program whose objective is to determine whether Computational Fluid Dynamic (CFD) models can be employed to accurately predict the airflow patterns within rapid development headings. In particular, the project aims to investigate the optimum set back distances for the ducts in order to adequately ventilate the face of the drivage. To validate the accuracy of the CFD model simulations measurements were obtained from a series of experiments performed on both scale models and within a full-scale surface gallery. The experimental scale-modeling program included making a series of pressure measurements across the face of the model for equivalent forcing duct setback distances of 5, 10 and 15 m (16, 33 and 50 ft). This pressure data was then plotted as contour plots and compared with the corresponding CFD predictions. A series of full-scale auxiliary ventilation trials were performed within a modified surface gallery. Three-dimensional velocity measurements were taken across a number of cross-sections using an ultrasonic anemometer. Velocity measurements were obtained for three forcing duct setback distances and for a typical force-exhaust overlap configuration

Diffusion of particles in an expanding sphere with an absorbing boundary

We study the problem of particles undergoing Brownian motion in an expanding sphere whose surface is an absorbing boundary for the particles. The problem is akin to that of the diffusion of impurities in a grain of polycrystalline material undergoing grain growth. We solve the time dependent diffusion equation for particles in a d-dimensional expanding sphere to obtain the particle density function (function of space and time). The survival rate or the total number of particles per unit volume as a function of time is evaluated. We have obtained particular solutions exactly for the case where d=3 and a parabolic growth of the sphere. Asymptotic solutions for the particle density when the sphere growth rate is small relative to particle diffusivity and vice versa are derived.Comment: 12 pages. To appear in J. Phys. A: Math. Theor. 41 (2008

'It's a Form of Freedom': The experiences of people with disabilities within equestrian sport

This paper explores the embodied, gendered experiences of disabled horse‐riders. Drawing on data from five in‐depth interviews with paradressage riders, the ways in which their involvement in elite disability sport impacts upon their sense of identity and confidence are explored, as well as the considerable health and social benefits that this involvement brings. Social models of disability are employed and the shortcomings of such models, when applied to disability sport, are highlighted. The data presented here demonstrates the necessity of seeing disability sport as an embodied experience and acknowledging the importance of impairment to the experiences of disabled athletes. Living within an impaired body is also a gendered experience and the implications of this when applied to elite disability sport are considered