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The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Dense granular flows can spontaneously self-channelise by forming a pair of parallel-sided static levees on either side of a central flowing channel. This process prevents lateral spreading and maintains the flow thickness, and hence mobility, enabling the grains to run out considerably further than a spreading flow on shallow slopes. Since levees commonly form in hazardous geophysical mass flows, such as snow avalanches, debris flows, lahars and pyroclastic flows, this has important implications for risk management in mountainous and volcanic regions. In this paper an avalanche model that incorporates frictional hysteresis, as well as depth-averaged viscous terms derived from the
-rheology, is used to quantitatively model self-channelisation and levee formation. The viscous terms are crucial for determining a smoothly varying steady-state velocity profile across the flowing channel, which has the important property that it does not exert any shear stresses at the levee–channel interfaces. For a fixed mass flux, the resulting boundary value problem for the velocity profile also uniquely determines the width and height of the channel, and the predictions are in very good agreement with existing experimental data for both spherical and angular particles. It is also shown that in the absence of viscous (second-order gradient) terms, the problem degenerates, to produce plug flow in the channel with two frictionless contact discontinuities at the levee–channel margins. Such solutions are not observed in experiments. Moreover, the steady-state inviscid problem lacks a thickness or width selection mechanism and consequently there is no unique solution. The viscous theory is therefore a significant step forward. Fully time-dependent numerical simulations to the viscous model are able to quantitatively capture the process in which the flow self-channelises and show how the levees are initially emplaced behind the flow head. Both experiments and numerical simulations show that the height and width of the channel are not necessarily fixed by these initial values, but respond to changes in the supplied mass flux, allowing narrowing and widening of the channel long after the initial front has passed by. In addition, below a critical mass flux the steady-state solutions become unstable and time-dependent numerical simulations are able to capture the transition to periodic erosion–deposition waves observed in experiments.
To increase the proportion of patients with no psychotropic drug discrepancies at the community mental health team (CMHT)–general practice interface. Three CMHTs participated. Over a 14 month period, quality improvement methodologies were used: individual patient-level feedback to patient's prescribers, run charts and meetings with CMHTs.
One CMHT improved medicines reconciliation accuracy and demonstrated significant reductions in prescribing discrepancies. One in three (119/356) patients had ≥1 discrepancy involving 20% (166/847) of all prescribed psychotropics. Discrepancies were graded as: ‘fatal’ (0%), ‘serious’ (17%) and ‘negligible/minor harm’ (83%) but were associated with extra avoidable prescribing costs. For medicines routinely supplied by secondary care, 68% were not recorded in general practice electronic prescribing systems.
Improvements in medicines reconciliation accuracy were achieved for one CMHT. This may have been partly owing to a multidisciplinary team approach to sharing and addressing prescribing discrepancies. Improving prescribing accuracy may help to reduce avoidable drug-related harms to patients.
Authentic learning is an approach to teaching where the learning is embedded in a real world context, in real situations or simulations, and offers students opportunities for problem solving challenges much like they will encounter in real life. This paper discusses and reflects upon the development a course designed to teach Socially Responsible Design approaches, methods and tools to Product Design Engineering students using global projects. Our research question was to investigate if this Socially Responsible Design course, it's structure, delivery, learning activities and assessments combined to deliver an authentic learning experience. Through informal interviews with staff, review of student reflections, review of university student feedback comments and consideration of final outcomes, all within the framework of Herrington and Oliver's nine elements of authentic learning, we found that this course did provide an authentic learning experience for many reasons. This study offers academics a frame work for reviewing existing and future courses with a view to creating or enhancing authentic learning experiences using project based learning
When a layer of static grains on a sufficiently steep slope is disturbed, an upslope-propagating erosion wave, or retrogressive failure, may form that separates the initially static material from a downslope region of flowing grains. This paper shows that a relatively simple depth-averaged avalanche model with frictional hysteresis is sufficient to capture a planar retrogressive failure that is independent of the cross-slope coordinate. The hysteresis is modelled with a non-monotonic effective basal friction law that has static, intermediate (velocity decreasing) and dynamic (velocity increasing) regimes. Both experiments and time-dependent numerical simulations show that steadily travelling retrogressive waves rapidly form in this system and a travelling wave ansatz is therefore used to derive a one-dimensional depth-averaged exact solution. The speed of the wave is determined by a critical point in the ordinary differential equation for the thickness. The critical point lies in the intermediate frictional regime, at the point where the friction exactly balances the downslope component of gravity. The retrogressive wave is therefore a sensitive test of the functional form of the friction law in this regime, where steady uniform flows are unstable and so cannot be used to determine the friction law directly. Upper and lower bounds for the existence of retrogressive waves in terms of the initial layer depth and the slope inclination are found and shown to be in good agreement with the experimentally determined phase diagram. For the friction law proposed by Edwards et al. (J. Fluid. Mech., vol. 823, 2017, pp. 278–315, J. Fluid. Mech., 2019, (submitted)) the magnitude of the wave speed is slightly under-predicted, but, for a given initial layer thickness, the exact solution accurately predicts an increase in the wave speed with higher inclinations. The model also captures the finite wave speed at the onset of retrogressive failure observed in experiments.
Disease surveillance in wildlife populations presents a logistical challenge, yet is critical in gaining a deeper understanding of the presence and impact of wildlife pathogens. Erinaceus coronavirus (EriCoV), a clade C Betacoronavirus, was first described in Western European hedgehogs (Erinaceus europaeus) in Germany. Here, our objective was to determine whether EriCoV is present, and if it is associated with disease, in Great Britain (GB). An EriCoV-specific BRYT-Green® real-time reverse transcription PCR assay was used to test 351 samples of faeces or distal large intestinal tract contents collected from casualty or dead hedgehogs from a wide area across GB. Viral RNA was detected in 10.8% (38) samples; however, the virus was not detected in any of the 61 samples tested from Scotland. The full genome sequence of the British EriCoV strain was determined using next generation sequencing; it shared 94% identity with a German EriCoV sequence. Multivariate statistical models using hedgehog case history data, faecal specimen descriptions and post-mortem examination findings found no significant associations indicative of disease associated with EriCoV in hedgehogs. These findings indicate that the Western European hedgehog is a reservoir host of EriCoV in the absence of apparent disease.
Traditionally x-ray spectrometers have been designed to analyze perfectly prepared specimens that are flat and highly polished such as 32mm discs. Certainly the best analytical results are obtained on such samples, however in an industrial laboratory it is also neccessary to obtain statistically valid results on samples that are less than ideal in size and geometry. The problem at the TRIDENT Refit Facility is to analyze large metal parts such as pump casings, valve bodys, flanges, and finished piping sections that are going into the repair of TRIDENT class submarines. Energy dispersive X-ray techniques have long been recognized as fast and non-destructive and are therefore ideally suited to the analysis of these finished metal parts.
Laser-based compact MeV X-ray sources are useful for a variety of applications such as radiography and active interrogation of nuclear materials. MeV X rays are typically generated by impinging the intense laser onto ~mm-thick high-Z foil. Here, we have characterized such a MeV X-ray source from 120 TW (80 J, 650 fs) laser interaction with a 1 mm-thick tantalum foil. Our measurements show X-ray temperature of 2.5 MeV, flux of 3 × 1012 photons/sr/shot, beam divergence of ~0.1 sr, conversion efficiency of ~1%, that is, ~1 J of MeV X rays out of 80 J incident laser, and source size of 80 m. Our measurement also shows that MeV X-ray yield and temperature is largely insensitive to nanosecond laser contrasts up to 10−5. Also, preliminary measurements of similar MeV X-ray source using a double-foil scheme, where the laser-driven hot electrons from a thin foil undergoing relativistic transparency impinging onto a second high-Z converter foil separated by 50–400 m, show MeV X-ray yield more than an order of magnitude lower compared with the single-foil results.
Volume 34 of Arthurian Literature presents essays that revisit the familiar and introduce the unfamiliar, ranging from Chrétien's Erec et Enide, Sir Gawain and the Green Knight and Malory to a hitherto unpublished Middle English poem on Arthur's drawing of the sword from the stone and a little-known Irish Arthurian text, plus a re-evaluation of the cross supposedly found in Arthur's grave at Glastonbury.
Rebecca Newby's examination of the ending of Chrétien's Erec et Enide constitutes a case study in which she explores the extent to which Chrétien's endings conform to medieval theories of poetic composition, with an eye to discovering whether ‘they do in fact contain a nucleus of poetic truth or not’. She studies the structure of Chrétien's poem, paying special attention to endings – both ‘illusory’ and ‘actual’ – and argues that Erec and Enide are also ‘symbolic figures’, or ‘allegorical apotheoses of chivalric matière and beautiful poetic, form respectively’. Neil Cartlidge asks several questions of the opening frame of Sir Gawain and the Green Knight, most notably regarding the identity of the knight who is said by the narrator to have committed an act of treason. Can he be identified? The poem's earliest editors decided on either Aeneas or Antenor, but Cartlidge argues for a new approach to this question, and comes to the striking conclusion that the person who best fits the profile within the context of the Fall of Troy narrative is in fact Paris. Nicole Clifton reads Sir Gawain's deathbed scene in Malory's Morte Darthur, offering an answer to the question of how Gawain knows the exact hour of his death. His prediction, according to Clifton, is neither prophetic nor symbolic, as other critics have argued, but simply a matter of factual observation. Furthermore, she argues that Arthur's subsequent dream of Gawain need not necessarily amount to prophecy on Gawain's part either, as some would have it, but has instead a pragmatic explanation as well. Clifton concludes that such passages point to Malory being ‘a hard-headed knight-prisoner whose real-life experience inflects his reading of assorted French books’, rather than ‘a nostalgic writer in love with “olde romaunce” ’.