[1] This work presents new water surface elevation data including evidence of the spatial correlation of water surface waves generated in shallow water flows over a gravel bed without appreciable bed forms. Careful laboratory experiments have shown that these water surface waves are not well-known gravity or capillary waves but are caused by a different physical phenomenon. In the flow conditions studied, the shear present in shallow flows generates flow structures, which rise and impact on the water-air interface. It is shown that the spatial correlation function observed for these water surface waves can be approximated by the following analytical expression W( ) = e -2 / 2 2 w cos(2 L -1 0 ). The proposed approximation depends on the spatial correlation radius, w , characteristic spatial period, L 0 , and spatial lag, . This approximation holds for all the hydraulic conditions examined in this study. It is shown that L 0 relates to the depth-averaged flow velocity and carries information on the shape of the vertical velocity profile and bed roughness. It is also shown that w is related to the hydraulic roughness and the flow Reynolds number.

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Understanding the dynamic free surface of geophysical flows has the potential to enable direct inference of the flow properties based on measurements of the free surface. An important step is to understand the inherent response of free surfaces in depth-limited flows. Here a model is presented to demonstrate that free surface oscillatory spatial correlation patterns result from individual surface features oscillating vertically as they advect over space and time. Comparison with laboratory observations shows that these oscillating surface features can be unambiguously explained by simple harmonic motion, whereby the oscillation frequency is controlled by the root-mean-square water surface fluctuation, and to a lesser extent the surface tension. This demonstrates that the observed "complex" wave pattern can be simply described as an ensemble of spatially and temporally distributed oscillons. Similarities between the oscillon frequency and estimated frequency of near-bed bursting events suggest that oscillon behaviour is linked with the creation of coherent flow structures.

Background: Evidence of climate change and its impact continues to be accumulated, and it is argued that the consequences of climate change are likely to result in an increased demand on health services. It has been claimed that climate change presents new challenges for health services and that strategies should be adopted to address these challenges. Aim:The aim of this systematic review was to map published literature on health, climate change and sustainability by categorising papers according to their focus on effects, strategy and actions, and to provide a thematic analysis of their content.Methods: Systematic searches were conducted via a range of healthcare related databases i.e. Pubmed, Medline, CINAHL, AMED, ASSIA, IBSS and ISI Web of Knowledge. Searches focussed upon papers published in English between 1998 and 2008. Retrieved papers were studied by the authors in order to inform the thematic analysis of their content.Results: A total of 114 publications were retrieved, of which 36 met the inclusion criteria for the systematic review. These 36 publications were categorised and are discussed according to their focus on: effects/impacts, strategy/policy, action/examples. Conclusions:A number of papers report the potential health effects of climate change while others report policies and strategies to tackle these effects. However there is an urgent need to identify and report on the implementation of strategies to mitigate and adapt to these challenges and to publish real examples of actions. Actions that are taken need to be evidence/policy based, and implementations monitored, evaluated and published.

In this paper, the smoothed particle hydrodynamics method is used to simulate experimental shallow free surface turbulent flows over a rough bed made of regularly packed uniform spheres. The numerical program is based on the open source code SPHysics and significant improvement is made in the turbulence modelling and rough bed treatment within the code. A modified sub-particle-scale eddy viscosity model is proposed to simulate the effect of turbulence transfer mechanisms in the highly-sheared free surface flow, and a drag force term is introduced into the momentum equation as a source term to account for the existence of the bed roughness. To validate the numerical model, a laboratory experiment is carried out to study shallow, turbulent flow behaviour under different flow conditions. The SPH simulations are then compared with the flow velocity, shear stress and turbulent intensity profiles measured via acoustic doppler velocimeters. Several issues with regard to the rough bed hydraulics are investigated, including the study of water surface behaviour and its interaction with the bulk flow.

Avalanche fatalities have increased. This is most likely related to an overall rise in backcountry utilization. Fatalities have increased among snowmobilers and snowboarders. Despite a rise in backcountry utilization, avalanche fatalities in Colorado are decreasing. A strategy of focused training and education aimed toward at-risk groups could result in lower avalanche fatalities.

Objectives: This study explores the financial consequences of decreased acute care utilization and expanded community-based care for patients at the end of life in England. Method: A Markov model based on cost and utilization data was used to estimate the costs of care for cancer and organ failure in the last year of life and to simulate reduced acute care utilization. Results: We estimated at £1.8 billion the cost to the taxpayer of care for the 127,000 patients dying from cancer in 2006. The equivalent cost for the 30,000 people dying from organ failure was £553 million. Resources of £16 to £171 million could be released for cancer. Conclusion: People generally prefer to die outside hospital. Our results suggest that reducing reliance on acute care could release resources and better meet peoples’ preferences. Better data on the cost-effectiveness of interventions are required. Similar models would be useful to decision-makers evaluating changes in service provision.

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