Robust point correspondence applied to two and three-dimensional image registration

Accurate and robust correspondence calculations are very important in many medical and biological applications. Often, the correspondence calculation forms part of a rigid registration algorithm, but accurate correspondences are especially important for elastic registration algorithms and for quantifying changes over time. In this paper, a new correspondence calculation algorithm, CSM (correspondence by sensitivity to movement), is described. A robust corresponding point is calculated by determining the sensitivity of a correspondence to movement of the point being matched. If the correspondence is reliable, a perturbation in the position of this point should not result in a large movement of the correspondence. A measure of reliability is also calculated. This correspondence calculation method is independent of the registration transformation and has been incorporated into both a 2D elastic registration algorithm for warping serial sections and a 3D rigid registration algorithm for registering pre and postoperative facial range scans. These applications use different methods for calculating the registration transformation and accurate rigid and elastic alignment of images has been achieved with the CSM method. It is expected that this method will be applicable to many different applications and that good results would be achieved if it were to be inserted into other methods for calculating a registration transformation from correspondence

An analytical model for bore-driven run-up

We use a hodograph transformation and a boundary integral method to derive a new analytical solution to the shallow-water equations describing bore-generated run-up on a plane beach. This analytical solution differs from the classical Shen-Meyer runup solution in giving significantly deeper and less asymmetric swash flows, and also by predicting the inception of a secondary bore in both the backwash and the uprush in long surf. We suggest that this solution provides a significantly improved model for flows including swash events and the run-up following breaking tsunamis

The undertakers: Learning from an unusual work experience placement

Providing care for dying patients and their families is a fundamental part of general practice. There are barriers to the effective provision of such care at both individual and organisational levels (Mitchell et al., 2016), as well as cultural and social barriers to discussing the end of life and dying (www.dyingmatters.org). The extent to which we are exposed to death during training is highly variable, and the way that we are educated to cope with both the practicalities and the emotional aspects of death and dying receives little attention in undergraduate or postgraduate training

Long-Wave Forcing by the Breaking of Random Gravity Waves on a Beach

This paper presents new laboratory data on long-wave (surf-beat) forcing by the random breaking of shorter gravity water waves on a plane beach. The data include incident and outgoing wave amplitudes, together with shoreline oscillation amplitudes at long-wave frequencies, from which the correlation between forced long waves and short-wave groups is examined. A detailed analysis of the cross-shore structure of the long-wave motion is presented, and the observations are critically compared with existing theories for two-dimensional surf-beat generation. The surf beat shows a strong dependency on normalized surf-zone width, consistent with long-wave forcing by a time-varying breakpoint, with little evidence of the release and reflection of incident bound long waves for the random-wave simulations considered. The seaward-propagating long waves show a positive correlation with incident short-wave groups and are linearly dependent on short-wave amplitude. The phase relationship between the incident bound long waves and radiated free long waves is also consistent with breakpoint forcing. In combination with previous work, the present data suggest that the breakpoint variability may be the dominant forcing mechanism during conditions with steep incident short waves

General solutions for the initial run-up of a breaking tsunami front

An assessment of potential damage on coastlines due to tsunami requires prediction of the likely flow depths and impact forces on structures. Since tsunami have a long wavelength relative to the water depth, models that solve the non-linear shallow water equations (NLSWE) are appropriate. Carrier et al (2003) presented solutions for tsunami that do not break. However, where the leading front of the tsunami breaks, the wave front is more similar to a bore approaching the shoreline. An analytical treatment for the run-up driven by an incident bore was developed by Shen & Meyer (1963). However, the Shen & Meyer result is only unique close to the shoreline, and the flow depths and velocities depend on the seaward boundary condition. Here, a new numerical model is presented that solves the NLSWE for the case of a broken tsunami front arriving at the shoreline. It is a simple model that allows specification of either the flow depths or velocities at the seaward boundary, and the solution method allows the effects of friction to be incorporated. The model is able to reproduce the Shen & Meyer analytical solution for the initial motion of the shoreline. The potential damage to coastal structures and other infrastructure may be assessed by calculation of impact and drag forces due to the predicted flow depths and velocities

Self-regulation of driving and its relationship to driving ability among older adults

Although it is known that older drivers limit their driving, it is not known whether this self-regulation is related to actual driving ability. A sample of 104 older drivers, aged between 60 and 92, completed a questionnaire about driving habits and attitudes. Ninety of these drivers also completed a structured on-road driving test. A measure of self-regulation was derived from drivers’ self-reported avoidance of difficult driving situations. The on-road driving test involved a standard assessment used to determine fitness to drive. Of the 90 participants who completed the driving assessment, 68 passed the test, eight passed but were recommended to have driving lessons and 14 failed. Driving test scores for the study were based on the number of errors committed in the driving tests, with weightings given according to the seriousness of the errors. The most commonly avoided difficult driving situations were parallel parking and driving at night in the rain, while the least avoided situation was driving alone. Poorer performance on the driving test was not strongly related to overall avoidance of difficult driving situations. Stronger relationships were found between driving ability and avoidance of specific difficult driving situations. These specific driving situations were the ones in which the drivers had low confidence and that the drivers were most able to avoid if they wished to. These results may reflect a tendency for those with poorer driving ability to lose confidence in their driving, and begin to avoid difficult driving situations. However, there are a number of situations that drivers find difficult to avoid.M.R.J. Baldock, J.L. Mathias, A.J. McLean, A. Bernd

Integrating Augmented Reality into bioscience education

Visualisation of 3-dimensional (3D) molecules has traditionally been taught using 2D images, which often fail to convey the intricate complexity of structure-to-function relationships. Augmented Reality provides a platform to bring 3D protein structures into the class to aid biosciences education