Nondestructive spot test method for magnesium and magnesium alloys

A method for spot test identification of magnesium and various magnesium alloys commonly used in aerospace applications is described. The spot test identification involves color codes obtained when several drops of 3 M hydrochloric acid are placed on the surface to be tested. After approximately thirty seconds, two drops of this reacted acid is transferred to each of two depressions in a spot plate for additions of other chemicals with subsequent color changes indicating magnesium or its alloy

Person-centred advocacy: Some ethical issues

In the second of two articles on advocacy for people with dementia Mike Fox with Lesley Wilson considers some of the ethical issues arising from advocacy work within a residential home that was due to close

Person-centred advocacy for people with dementia - a personal account

In the first of two articles on advocacy for people with dementia, Mike Fox and Lesley Wilson describe an advocacy project based in a residential home and consider the issues and themes that arose

Critical superfluid velocity in a trapped dipolar gas

We investigate the superfluid properties of a dipolar Bose-Einstein condensate (BEC) in a fully three-dimensional trap. Specifically, we calculate a superfluid critical velocity for this system by applying the Landau criterion to its discrete quasiparticle spectrum. We test this critical velocity by direct numerical simulation of condensate depletion as a blue-detuned laser moves through the condensate. In both cases, the presence of the roton in the spectrum serves to lower the critical velocity beyond a critical particle number. Since the shape of the dispersion, and hence the roton minimum, is tunable as a function of particle number, we thereby propose an experiment that can simultaneously measure the Landau critical velocity of a dipolar BEC and demonstrate the presence of the roton in this system.Comment: 5 pages, 4 figures, version accepted to PR

Density-Dependent Response of an Ultracold Plasma to Few-Cycle Radio-Frequency Pulses

Ultracold neutral plasmas exhibit a density-dependent resonant response to applied radio-frequency (RF) fields in the frequency range of several MHz to hundreds of MHz for achievable densities. We have conducted measurements where short bursts of RF were applied to these plasmas, with pulse durations as short as two cycles. We still observed a density-dependent resonant response to these short pulses. However, the too rapid timescale of the response, the dependence of the response on the sign of the driving field, the response as the number of pulses was increased, and the difference in plasma response to radial and axially applied RF fields are inconsistent with the plasma response being due to local resonant heating of electrons in the plasma. Instead, our results are consistent with rapid energy transfer from collective motion of the entire electron cloud to electrons in high-energy orbits. In addition to providing a potentially more robust way to measure ultracold neutral plasma densities, these measurements demonstrate the importance of collective motion in the energy transport in these systems.Comment: 5 pages, 4 figure

Projections and Dyadic Parseval Frame MRA Wavelets

A classical theorem attributed to Naimark states that, given a Parseval frame $\mathcal{B}$ in a Hilbert space $\mathcal{H}$, one can embed $\mathcal{H}$ in a larger Hilbert space $\mathcal{K}$ so that the image of $\mathcal{B}$ is the projection of an orthonormal basis for $\mathcal{K}$. In the present work, we revisit the notion of Parseval frame MRA wavelets from two papers of Paluszy\'nski, \v{S}iki\'c, Weiss, and Xiao (PSWX) and produce an analog of Naimark's theorem for these wavelets at the level of their scaling functions. We aim to make this discussion as self-contained as possible and provide a different point of view on Parseval frame MRA wavelets than that of PSWX.Comment: 19 page

Safe use of symbols in handover documentation for medical teams

Concern has been reported about the safe use of medical abbreviations in documents such as handover sheets and medical notes, especially when information is being communicated between staff of different specialties (BBC 2008, Sheppard et al. 2008). This article describes a study to investigate whether the use of symbols in handover documentation that is shared within and between multidisciplinary teams (MDTs) has similar safety implications. We asked 19 healthcare professionals from a range of specialties to identify 45 different combinations of 38 individual symbols. The symbols and combinations of symbols were extracted from 102 handover sheets taken from 6 different healthcare contexts in 4 London hospitals. Three symbols proposed in Microsoft's Common User Interface guidelines for alert symbols were also included. Results reveal that while some symbols are well understood, many others are either ambiguous or unknown. These results have implications for the safe use of symbols in medical documents, including paper and electronic handover documents and Electronic Patient Records (EPRs), especially where teams comprise individuals from different professional backgrounds, i.e. MDTs. We offer initial suggestions for standardisation and further research