Doppler Tomography of Dwarf Nova IY UMa during Quiescence

Quiescent Doppler tomography of the newly discovered deeply-eclipsing SU UMa system IY UMa reveals properties of the region where the accretion stream from the donor impacts the edge of the disc. A very strong bright spot is produced and the Keplerian disc emission in the impact region is disrupted or obscured. The differing properties of Halpha, Hbeta and He I emission will allow physical parameters of the converging flow region to be studied.Comment: 6 pages, 5 figures. To appear in Proceedings of Astro-Tomography Workshop, Brussels, July 2000, Eds. H. Boffin, D. Steeghs, Springer-Verlag Lecture Notes in Physic

An investigation into a bentonite clay based geosynthetic liner in a caustic refinery environment

Bauxite residue (red mud) management is a major environmental issue for alumina refineries. The global average for residue storage can cover in excess of 2.1 million square metres per refinery and is increasing annually by 300 to 400 thousand square metres. Residue has the potential to damage surface and groundwater quality due to the residue’s high alkalinity. Bauxite residue drying areas (RDAs) need to be designed in a manner that is safe for the population and the natural environment. Currently, RDA construction practice relies on the placement of a minimum of two clay lifts, a constructed low permeability base and an embankment seal that is at least equivalent to a 0.5m depth of mechanically compacted clay with a permeability coefficient of less than 10-9m/sec. This is overlain with a high-density polyethylene (HDPE) geomembrane, as the primary seal against seepage of caustic liquor. In Western Australia it is becoming increasingly difficult to source sufficient clay for future RDA constructionTo continue to meet and improve on current community and environmental standards, this investigation proposes an alternative to the clay lining system. A factory prehydrated geosynthetic liner (GCL) was evaluated in terms of its feasibility and its use in the design of a RDA, which would reduce the dependency on the sourcing of mass volumes of high quality clay from potentially long distances. The investigation also reviews the use of the GCL in a structural application, utilising it as a secondary containment measure under concrete bunds containing alumina process tanks

Heliocentric Escape and Lunar Impact from Near Rectilinear Halo Orbits

Spacecraft departing from the Gateway in a Near Rectilinear Halo Orbit (NRHO) experience gravitational forces from the Moon, the Earth, and the Sun, all of which can be simultaneously significant. These complex dynamics influence the post-separation risk of recontact with the Gateway and the eventual destinations of the departing spacecraft. The current investigation examines the flow of objects leaving NRHOs in the Bicircular Restricted Four-Body Problem, and results are applied to heliocentric escape and lunar impact trajectories in a higher-fidelity ephemeris model. Separation maneuver magnitude, direction, and location are correlated with risk of recontact with the Gateway and successful departure to various destinations

Transcriptional profiling of colicin-induced cell death of Escherichia coli MG1655 identifies potential mechanisms by which bacteriocins promote bacterial diversity

We report the transcriptional response of Escherichia coli MG1655 to damage induced by colicins E3 and E9, bacteriocins that kill cells through inactivation of the ribosome and degradation of chromosomal DNA, respectively. Colicin E9 strongly induced the LexA-regulated SOS response, while colicin E3 elicited a broad response that included the induction of cold shock genes, symptomatic of translational arrest. Colicin E3 also increased the transcription of cryptic prophage genes and other laterally acquired mobile elements. The transcriptional responses to both these toxins suggest mechanisms that may promote genetic diversity in E. coli populations, pointing to a more general role for colicins in adaptive bacterial physiology than has hitherto been realized

Establishment of leucaena in Australia

Leucaena (Leucaena leucocephala ssp. glabrata) is a highly productive tropical perennial legume used primarily in extensive beef grazing systems across northern Australia. Its productivity provides substantial benefits to grazing businesses and economically significant areas of leucaena have been established in Queensland, with much smaller areas in both the Northern Territory and Western Australia. Specific environmental conditions (particularly soil type) and management practices are required to obtain reliable establishment and high productivity from leucaena-grass grazing systems. Significant research, development and extension have been undertaken in northern Australia, particularly in central Queensland, resulting in management packages which ensure establishment reliability and long-term productivity. However expansion into new areas can be constrained by regionally-specific establishment issues. Adaptation of known establishment and management practices together with research and development are required for leucaena-grass grazing systems in new regions

PIRATE: A Remotely-Operable Telescope Facility for Research and Education

We introduce PIRATE, a new remotely-operable telescope facility for use in research and education, constructed from 'off-the-shelf' hardware, operated by The Open University. We focus on the PIRATE Mark 1 operational phase where PIRATE was equipped with a widely- used 0.35m Schmidt-Cassegrain system (now replaced with a 0.425m corrected Dall Kirkham astrograph). Situated at the Observatori Astronomic de Mallorca, PIRATE is currently used to follow up potential transiting extrasolar planet candidates produced by the SuperWASP North experiment, as well as to hunt for novae in M31 and other nearby galaxies. It is operated by a mixture of commercially available software and proprietary software developed at the Open University. We discuss problems associated with performing precision time series photometry when using a German Equatorial Mount, investigating the overall performance of such 'off-the-shelf' solutions in both research and teaching applications. We conclude that PIRATE is a cost-effective research facility, and also provides exciting prospects for undergraduate astronomy. PIRATE has broken new ground in offering practical astronomy education to distance-learning students in their own homes.Comment: Accepted for publication in PASP. 14 pages, 11 figure

Effects of temperature in relation to sheet metal stamping

The demand to reduce the use of lubricants and increase tool life in sheet metal stamping has resulted in increased research on the sliding contact between the tool and the sheet materials. Unlubricated sliding wear tests for soft carbon steel sliding on D2 tool steel were performed using a pin-on-disk tribometer. The results revealed that temperature has an influencing role in the wear of tool steel and that material transfer between tool and sheet can be minimized at a certain temperature range in sheet metal stamping

The detection of the donor star in IY UMa

We present the results of a search for the donor star in the high inclination SU UMa type cataclysmic variable IY UMa. We detect absorption features in the near infrared consistent with an M type dwarf donor star. Using the skew mapping technique to exploit the velocity information provided by the 8183-8194 Angstrom Na I absorption doublet, we locate the absorption at the expected donor velocity of IY UMa.Comment: 5 pages, 4 figures, accepted for publication in MNRA

Restenosis treatments using nanoparticle-based drug delivery systems

Restenosis, the re-narrowing of a blood vessel after removal of atherosclerotic plaque, is a major limitation of surgical treatments for atherosclerosis. Various attempts to prevent or treat restenosis by pharmacological or mechanical approaches have had limited success in clinical trials. Hence, there is wide interest in developing new strategies to prevent or treat restenosis. This review discusses 'a new-generation therapy' that uses functional nanoparticles to effectively deliver active drug molecules. The potential platforms for nanoparticle-based solutions to restenosis include organic (e.g. polymers, liposomes, and proteins) and inorganic nanoparticles (e.g. layered double hydroxides, titanium oxide nanotubes, and magnetic nanoparticles,). Many in vitro and in vivo studies based on these platforms demonstrate the feasibility and potential of using nanoparticle drug delivery systems for preventing or treating restenosis, but as yet few have reached clinical trials. It is suggested that using inorganic nanoparticles to target deliver multi-functional drugs will be a promising approach to preventing or treating restenosis

Mind the Gap

Mind the Gap sought to improve the metacognition and academic attainment of pupils in Year 4. There were two aspects to the intervention. The first involved training teachers in how to embed metacognitive approaches in their work, and how to continue to effectively and strategically involve parents. This training took place over a day and was provided by a consultant. The second component focused on parental engagement and offered families the opportunity to participate in a series of facilitated workshops where children and parents work together to create an animated film. Sessions were coordinated by a practitioner who helped participants to think about how they are learning, create learning goals and reflect on their progress; to be metacognitive about the learning process they were engaged in together. The families were offered 2 hours of workshops per week for 5 weeks (10 hours in total). The project targeted schools in four areas of England: Birmingham, Devon, London and Manchester. It was delivered by the Campaign for Learning, with assessments carried out by Durham University. Delivery started in September 2012 and finished in October 2013. The project was evaluated using a randomised controlled trial, which compared the interventions to a ‘business-as-usual’ control group. It is important to note that it was eligibility for the animation course, not participation, that was randomised, so the results must be regarded as estimating the effect of being offered the animation course (alone or in combination with teacher training, as appropriate) rather than participating in it