Visualising the South Yorkshire floods of ‘07

This paper describes initial work on developing an information system to gather, process and visualise various multimedia data sources related to the South Yorkshire (UK) floods of 2007. The work is part of the Memoir project which aims to investigate how technology can help people create and manage long-term personal memories. We are using maps to aggregate multimedia data and to stimulate remembering past events. The paper describes an initial prototype; challenges faced so far and planned future work

Potential for the Vishniac instability in ionizing shock waves propagating into cold gases

The Vishniac instability was posited as an instability that could affect supernova remnants in their late stage of evolution when subject to strong radiative cooling, which can drive the effective ratio of specific heats below 1.3. The potential importance of this instability to these astrophysical objects has motivated a number of laser-driven laboratory studies. However, the Vishniac instability is essentially a dynamical instability that should operate independently of whatever physical processes happen to reduce the ratio of specific heats. In this paper, we examine the possibility that ionization and molecular dissociation processes can achieve this, and we show that this is possible for a certain range of shock wave Mach numbers for ionizing/dissociating shock waves propagating into cold atomic and molecular gases

The effect of grading the atomic number at resistive guide element interface on magnetic collimation

Using 3 dimensional numerical simulations, this paper shows that grading the atomic number and thus the resistivity at the interface between an embedded high atomic number guide element and a lower atomic number substrate enhances the growth of a resistive magnetic field. This can lead to a large integrated magnetic flux density, which is fundamental to confining higher energy fast electrons. This results in significant improvements in both magnetic collimation and fast-electron-temperature uniformity across the guiding. The graded interface target provides a method for resistive guiding that is tolerant to laser pointing

High prevalence of penicillin-nonsusceptible Streptococcus pneumoniae at a community hospital in Oklahoma.

During 1997, Oklahoma City's Hospital A reported penicillin-nonsusceptible Streptococcus pneumoniae in almost 67% of isolates. To confirm this finding, all Hospital A S. pneumoniae isolates from October 23, 1997, through February 19, 1998, were tested for antibiotic susceptibility and repeat-tested at two other hospital laboratories. Medical records of Hospital A patients with invasive S. pneumoniae infections during 1994 through 1997 were also reviewed. These data were compared with 1998 statewide sentinel hospital surveillance data for invasive S. pneumoniae. Of 48 S. pneumoniae isolates from Hospital A during October 23, 1997, through February 19, 1998, 31 (65%) were penicillin-nonsusceptible S. pneumoniae, and 23 (48%) were highly penicillin resistant. Similar prevalences were confirmed at the other hospital laboratories; however, significant interlaboratory differences were noted in the determination of third-generation cephalosporin susceptibility. During 1994 through 1997, a trend toward increasing penicillin nonsusceptibility (p <0.05) was noted among S. pneumoniae isolates from nursing home patients. During 1998, 85 (30%) of 282 invasive isolates reported to the state surveillance system were penicillin-nonsusceptible S. pneumoniae; 33 (12%) were highly resistant. The increase in resistance observed is notable; the interlaboratory discrepancies are unexplained. To respond, a vaccination program was implemented at Hospital A, and vaccination efforts were initiated at nursing homes

Enhancement of keV X-rays from low-density cellulose triacetate (TAC) foam targets

The interaction of a high-power laser with a low-density foam target can in some instances result in a significant enhancement in x-ray generation relative to that when the same laser is incident upon a homogenous solid. In this paper, we present x-ray emission studies from foam targets where the density is varied from under-dense to over-dense. The targets are irradiated with the first harmonic of Nd:Glass laser. The laser intensity on the target was approximately 2 × 1014 W/cm2 with the pulse duration of 500 ps. Mass-matched cellulose triacetate foam targets with densities of 2 mg/cc, 4 mg/cc, 7 mg/cc, and 20 mg/cc were used. The areal density presented by the targets on the laser beam axis was held constant at 0.2 mg/cm2 by varying the target thickness in inverse proportion to the density. The x-ray yield in the spectral range (5-8 keV) and (4.5-16 keV) was found to be enhanced by approximately 2.3 times in foam targets with the density of 2 mg/cc (under-dense) compared with foam targets with the density of 20 mg/cc (over-dense)

The physical and chemical reclamation and recycling of elements from black aluminium furnace residues

Dross is the inevitable waste product generated by the world-wide primary and secondary aluminium industries. Around 3.5 million tonnes of white dross and 0.85 million tonnes of black dross are produced per year. Drosses are classified depending on metal content. White dross contains 40% and black dross contains 10% of aluminium. About half of the white dross is currently landfilled along with almost all of the black dross, and the annual cost to the UK industry of landfilling this waste is about £90 million per year. There is no commercially viable method of recovering the aluminium, which is potentially recyclable from these drosses, and no current conventional process has the custom-built capability to avoid their disposal to landfill. The practice of landfilling aluminium dross has raised problems for both industry and environment, because of potential leaching of heavy metals into groundwater from the landfill. The black dross has been physically and chemically characterised. The results show that the dross contains mostly metallic aluminium, aluminium nitride, alumina, sodium chloride, potassium chloride and silica with almost 50% of the dross being a mixture of sodium chloride and potassium chloride. A counter current leaching process has been developed to recycle the salts back to the secondary furnace. The environmental impact of black dross has been investigated using simulated landfill conditions. Leachability studies were carried out using water, and other leach media to model the following conditions: humic acid-containing systems, acid rain (pH 2.5), and acetic acid solutions (pH 5). Up to 60% of the dross was leached out in all media with the production of the saline solution providing the major impact. Only small amounts of aluminium were leached out under all these condition. No leachability behaviour was detected once the black dross was washed. So landfilling washed black dross can minimise both environmental and economical problems. Black dross residue, after washing with water, is enriched with alumina. Added value chemicals (of >95% purity) including aluminium hydroxide, alumina, aluminium chloride, aluminium nitrate, aluminium sulphate and aluminium carboxylates have been prepared using the washed black dross. Preliminary calculations have shown that the technology developed to recycle black dross to added-value chemicals is economically viable. A methodology has been developed which enables low grade alumnium waste, black dross, to be treated, commercially viable chemicals to be prepared, reagent use to be minimised through recycle and the diversion of millions of tonnes of furnace residue from landfill.EThOS - Electronic Theses Online ServiceCentre for Environmental Research through a DTI/EPSRC/WMR3 programmeGBUnited Kingdo

Simulated Learning for Clinical Skill Acquisition and Retention: Report on a Research Project with Trainee Medical Interns

This paper reports on a research project conducted at the Advanced Clinical Skills Centre, University of Auckland, to determine whether the provision of a carefully engineered integrated virtual reality simulator for male and female urinary catheter insertion would increase student confidence levels and competency for those two skills. We present a literature review that demonstrates the increasing importance of simulation in medical education whilst detailing the perceived benefits and drawbacks of using simulations in medical education. We then present our research methodology including student numbers, procedures followed during the research, forms of evaluation carried out during the research and the current research stage. We conclude with the difficulties encountered in our study and a statement concerning the current status of our research

Ion acceleration with radiation pressure in quantum electrodynamic regimes

The radiation pressure of next generation high-intensity lasers could efficiently accelerate ions to GeV energies. However, nonlinear quantum-electrodynamic effects play an important role in the interaction of these lasers with matter. We show that these quantum-electrodynamic effects lead to the production of a critical density pair-plasma which completely absorbs the laser pulse and consequently reduces the accelerated ion energy and efficiency by 30-50%

Enhancing relativistic electron beam propagation through the use of graded resistivity guides

We show, using three dimensional hybrid particle-in-cell simulations, that fast electron transport is improved in a resistive guide when using a linear decreasing gradient in the resistivity between the guide and substrate. We observe increased heating-at-depth along the guide and significantly reduced heating inhomogeneity. These improvements result from an increase in the width of the collimating magnetic field, improving fast electron confinement and limiting the growth of magnetic fields in the interior of the guide