Feedback through student essay competitions: what makes a good engineering lecturer?

The Engineering Subject Centre of the HE Academy has run student essay competitions for some years. In 2008 the title was ‘What makes a good engineering lecturer?’. This paper presents an analysis of the 43 submissions, carried out to identify the most commonly cited attributes and to present quotes that convey the spirit of the essays. The same title had been used for the first competition in 2004, and the outcomes of the 2008 competition are compared with those previously published for the 2004 award. The attributes most commonly identified across both sets of essays are use of real-world examples, approachability, enthusiasm, diversity of media, and good communication

Microwave-induced resistance oscillations and zero-resistance states in 2D electron systems with two occupied subbands

We report on theoretical studies of recently discovered microwave-induced resistance oscillations and zero resistance states in Hall bars with two occupied subbands. In the same results, resistance presents a peculiar shape which appears to have a built-in interference effect not observed before. We apply the microwave-driven electron orbit model, which implies a radiation-driven oscillation of the two-dimensional electron system. Thus, we calculate different intra and inter-subband electron scattering rates and times that are revealing as different microwave-driven oscillations frequencies for the two electronic subbands. Through scattering, these subband-dependent oscillation motions interfere giving rise to a striking resistance profile. We also study the dependence of irradiated magnetoresistance with power and temperature. Calculated results are in good agreement with experiments.Comment: 7 pages, 6 figure

Rare earth doped silica nanoparticles via thermolysis of a single source metallasilsesquioxane precursor

Rare earth metal doped silica nanoparticles have significant advantages over traditional organic dyes and quantum dots. Silsesquioxanes are promising precursors in the production of silica nanoparticles by thermolysis, due to their structural similarities with silica materials. This manuscript describes the production of a new Eu(3+)-based metallasilsesquioxane species and its use as a single source precursor in the thermolytic production of luminescent rare earth metal doped silica nanoparticles with characteristic emission in the visible region of the spectrum

A pilot investigation of load-carrying on the head and bone mineral density in premenopausal, black African women

Although the influence of weight bearing activity on bone mass has been widely investigated in white women, few studies have been conducted in black, African populations. We investigated bone mineral density (BMD) in black South African women, with and without a history of load-carrying on the head. We also investigated whether load carrying may offer protection against low BMD in users of injectable progestin contraception (IPC). Participants were 32 black, South African women (22.4±3.2 yrs). Load carrying history was determined by questionnaire and interview and participants were grouped as load carriers (LC; n=18) or non load carriers (NLC; n=14). Ten women were using IPC and 6 were load-carriers. Total body (TB), lumbar spine (LS) and total hip (H) BMD were measured by dual energy X-ray absorptiometry. There were no differences in BMD between LC and NLC, and after controlling for age and BMI using two-tailed partial correlations. IPC users had lower BMD at all sites compared to non IPC users (p<0.05) and there were no associations between load carrying and BMD in this group. When IPC users were excluded from analysis, LC had higher LS BMD than NLC (p<0.005). Correlations were found between the weight of load carried and LS BMD (r=0.743, p<0.005), and between years of load carrying and LS and TB BMD (r=0.563, r=0.538 respectively; both p<0.05). Load carrying on the head may offer osteogenic benefits to the spine but these benefits did not appear in women using IPC

Web Application for Visual Modeling of Discrete Event Systems

This research work has resulted in the development of a web application that enables discrete event systems simulation to be created using a Petri-object approach. It provides the development of a model in two stages. In the first stage, the dynamics of the classes of objects are created using Petri net. In the second stage, the model is composed of objects with given dynamics. The simulation algorithm is based on stochastic Petri net with multichannel transitions and is implemented using Ruby. The web application enables the design of the model's dynamics by manipulation with graphics objects and saving it not only as a graphics object but also as a program method. This greatly improves the overall performance of the simulation model development

A hierarchical mesh refinement technique for global 3-D spherical mantle convection modelling

A method for incorporating multi-resolution capabilities within pre-existing global 3-D spherical mantle convection codes is presented. The method, which we term "geometric multigrid refinement", is based upon the application of a multigrid solver on non-uniform, structured grids and allows for the incorporation of local high-resolution grids within global models. Validation tests demonstrate that the method is accurate and robust, with highly efficient solutions to large-scale non-uniform problems obtained. Significantly, the scheme is conceptually simple and straightforward to implement, negating the need to reformulate and restructure large sections of code. Consequently, although more advanced techniques are under development at the frontiers of mesh refinement and solver technology research, the technique presented is capable of extending the lifetime and applicability of pre-existing global mantle convection codes

Critical role of general practitioners in preventing readmission following emergency department alcohol screening and brief intervention management of alcohol-related problems

Introduction/Objectives: Alcohol screening and brief intervention (ASBI) strategies are useful in general practice (GP) but their effectiveness in the emergency department (ED) is unclear. We evaluated the effect of ED-based ASBI on re-admissions. Methods: 453 ED subjects exceeding the threshold score on the three-item Alcohol Use Disorders Identification Test-Consumption (females 3+: males 4+) were randomized. We conducted telephone follow-up at 1 and 3 months and recorded hospital events 6 months pre- and post-enrolment. Results: Median weekly alcohol use was 20 standard drinks (interquartile range (IQR) 9-45) on enrolment. After 3 months, 247 (55%) were able to be re-interviewed. Median alcohol use was 10 drinks (IQR 4-26). Six months later, subjects receiving ED-ASBI without GP follow-up had significantly greater risk of re-admission compared with those having GP follow-up (OR 1.68, 95%CI 1.06-2.65; P =.028). Conclusions: ASBI reduces the likelihood of ED re-presentation only in subjects who have GP follow-up. The study has been registered as a clinical trial (Australian and New Zealand Clinical Trial Registry ACTRN12617001254381)

Cooling of cryogenic electron bilayers via the Coulomb interaction

Heat dissipation in current-carrying cryogenic nanostructures is problematic because the phonon density of states decreases strongly as energy decreases. We show that the Coulomb interaction can prove a valuable resource for carrier cooling via coupling to a nearby, cold electron reservoir. Specifically, we consider the geometry of an electron bilayer in a silicon-based heterostructure, and analyze the power transfer. We show that across a range of temperatures, separations, and sheet densities, the electron-electron interaction dominates the phonon heat-dissipation modes as the main cooling mechanism. Coulomb cooling is most effective at low densities, when phonon cooling is least effective in silicon, making it especially relevant for experiments attempting to perform coherent manipulations of single spins.Comment: 9 pages, 5 figure

Critical role of general practitioners in preventing readmission following emergency department alcohol screening and brief intervention management of alcohol-related problems

Introduction/Objectives: Alcohol screening and brief intervention (ASBI) strategies are useful in general practice (GP) but their effectiveness in the emergency department (ED) is unclear. We evaluated the effect of ED-based ASBI on re-admissions. Methods: 453 ED subjects exceeding the threshold score on the three-item Alcohol Use Disorders Identification Test-Consumption (females 3+: males 4+) were randomized. We conducted telephone follow-up at 1 and 3 months and recorded hospital events 6 months pre- and post-enrolment. Results: Median weekly alcohol use was 20 standard drinks (interquartile range (IQR) 9-45) on enrolment. After 3 months, 247 (55%) were able to be re-interviewed. Median alcohol use was 10 drinks (IQR 4-26). Six months later, subjects receiving ED-ASBI without GP follow-up had significantly greater risk of re-admission compared with those having GP follow-up (OR 1.68, 95%CI 1.06-2.65; P =.028). Conclusions: ASBI reduces the likelihood of ED re-presentation only in subjects who have GP follow-up. The study has been registered as a clinical trial (Australian and New Zealand Clinical Trial Registry ACTRN12617001254381)

Optical and thermal infrared observations of six near-Earth asteroids in 2002

We present thermal infrared photometry and spectrophotometry of six Near-Earth Asteroids (NEAs) using the 3.8 in United Kingdom Infrared Telescope (UKIRT) together with quasi-simultaneous optical observations of five NEAs taken at the 1.0 m Jacobus Kapteyn Telescope (JKT). For Asteroid (6455) 1992 HE we derive a rotational period P = 2.736 +/- 0.002 h, and an absolute visual magnitude H = 14.32 +/- 0.24. For Asteroid 2002 HK12 we derive H = 18.22 (+0.37 -0.30). The Standard Thermal Model (STM), the Fast Rotating Model (FIRM) and the Near-Earth Asteroid Thermal Model (NEATM) have been fitted to the measured fluxes to derive albedos and effective diameters. The derived geometric albedos and effective diameters are (6455) 1992 HE: p(v) = 0.26 +/- 0.08, D-eff = 3.55 +/- 0.5 km; 1999 HF1: p(v) = 0.18 +/- 0.07, D-eff = 3.73 (+1.0. -0.5) km; 2000 ED104: p(v) = 0.18 +/- 0.05, D-eff = 1.21 +/- 0.2 km: 2002 HK12: p(v) = 0.24 (+0.25. -0.11), D-eff 0.62 +/- 0.2 km: 2002 NX18: p(v) = 0.031 +/- 0.009 D-eff = 2.24 +/- 0.3 km; 2002 QE(15): p(v) = 0.15 (+0.08, -0.06), D-eff = 1.94 +/- 0.4 km. The limitations of using the NEATM to observe NEAs at high phase angles are discussed. (c) 2004 Elsevier Inc. All rights reserved