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Operational and emerging capabilities for surface water flood forecasting
Surface water (or pluvial) flooding is caused by intense rainfall before it enters rivers or drainage systems. As the climate changes and urban populations grow, the number of people around the world at risk of surface water flooding is increasing. Although it may not be possible to prevent such flooding, reliable and timely flood forecasts can help improve preparedness and recovery. Unlike riverine and coastal flooding where forecasting methods are well established, surface water flood forecasting presents a unique challenge due to the high uncertainties around predicting the location, timing and impact of what are typically localised events.
Over the past five years, there has been rapid development of convection-permitting numerical weather prediction models, ensemble forecasting and computational ability. It is now theoretically feasible to develop operational surface water forecasting systems. This paper identifies three approaches to surface water forecasting utilising state of the art meteorological forecasts; empirical based scenarios, hydrological forecasts linked to pre-simulated impact scenarios, and, real-time hydrodynamic simulation. Reviewing operational examples of each approach provides an opportunity to learn from international best practice to develop targeted, impact-based, surface water forecasts to support informed decision-making.
Although the emergence of new meteorological and hydrological forecasting capabilities is promising, there remains a scientific limit to the predictability of convective rainfall. To overcome this challenge, we suggest that a re-thinking of the established role of flood forecasting is needed, alongside the development of interdisciplinary solutions for communicating uncertainty and making the best use of all available data to increase preparedness
Vibronic coupling explains the ultrafast carotenoid-to-bacteriochlorophyll energy transfer in natural and artificial light harvesters
The initial energy transfer in photosynthesis occurs between the
light-harvesting pigments and on ultrafast timescales. We analyze the
carotenoid to bacteriochlorophyll energy transfer in LH2 Marichromatium
purpuratum as well as in an artificial light-harvesting dyad system by using
transient grating and two-dimensional electronic spectroscopy with 10 fs time
resolution. We find that F\"orster-type models reproduce the experimentally
observed 60 fs transfer times, but overestimate coupling constants, which leads
to a disagreement with both linear absorption and electronic 2D-spectra. We
show that a vibronic model, which treats carotenoid vibrations on both
electronic ground and excited state as part of the system's Hamiltonian,
reproduces all measured quantities. Importantly, the vibronic model presented
here can explain the fast energy transfer rates with only moderate coupling
constants, which are in agreement with structure based calculations.
Counterintuitively, the vibrational levels on the carotenoid electronic ground
state play a central role in the excited state population transfer to
bacteriochlorophyll as the resonance between the donor-acceptor energy gap and
vibrational ground state energies is the physical basis of the ultrafast energy
transfer rates in these systems
A qualitative analysis of the enforcement of the regulation of nutrition and health claims made for foods and its implications for health
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. In common with local government organisations across the world, local authorities in the UK have responsibility for promoting health. A key part of this function is the frontline enforcement activities of officers responsible for compliance with health and nutrition claims. This study identifies attitudes, values and practices of enforcers: namely trading standards and environmental health officers, when faced with the problem of non-compliance with the Regulation. Semi-structured interviews with frontline enforcers from local authority regulatory services to investigate challenges with the enforcement of Regulation (EC) 1924/2006. Twenty participants were interviewed; sixteen were based in North West England and two in the North and two in the South of England. The participants were selected for their specialist knowledge and experience of enforcement of nutrition and health claims. Regulation (EC) No. 1924/2006 on nutrition and health claims presents particular challenges for enforcers seeking to apply an optimal strategy to flawed regulatory design. As with other regulations, when faced with non-compliance, enforcers, specifically trading standards and environmental health officers have a wide discretion to determine their response: ranging from the deterrent or accommodative styles of enforcement. The participants reported using advice rather than action and by doing so confronting their bifurcating identity of prosecutor and advisor. Enforcers used advice as a regulatory tool in enforcing the law relating to nutrition and health claims
Crystallization and preliminary X-ray diffraction analysis of the peripheral light-harvesting complex LH2 from Marichromatium purpuratum
LH2 from the purple photosynthetic bacterium Marichromatium (formerly known as Chromatium) purpuratum is an integral membrane pigment-protein complex that is involved in harvesting light energy and transferring it to the LH1-RC `core' complex. The purified LH2 complex was crystallized using the sitting-drop vapour-diffusion method at 294 K. The crystals diffracted to a resolution of 6 Å using synchrotron radiation and belonged to the tetragonal space group I4, with unit-cell parameters a = b = 109.36, c = 80.45 Å. The data appeared to be twinned, producing apparent diffraction symmetry I422. The tetragonal symmetry of the unit cell and diffraction for the crystals of the LH2 complex from this species reveal that this complex is an octamer
Toward the Restoration of Caribou Habitat: Understanding Factors Associated with Human Motorized Use of Legacy Seismic Lines
Populations of boreal and southern mountain caribou in Alberta, Canada, are declining, and the ultimate cause of their decline is believed to be anthropogenic disturbance. Linear features are pervasive across the landscape, and of particular importance, seismic lines established in the 1900s (legacy seismic lines) are slow to regenerate. Off-highway vehicles are widely used on these seismic lines and can hamper vegetative re-growth because of ongoing physical damage, compaction, and active clearing. Restoration of seismic lines within caribou range is therefore a priority for the recovery of threatened populations in Alberta, but a triage-type approach is necessary to prioritize restoration and ensure conservation resources are wisely spent. To target restoration efforts, our objective was to determine factors that best explained levels of off-highway vehicles use on seismic lines intersecting roads. We investigated the relative importance of local topography, vegetation attributes of seismic lines, and broad-scale human factors such as the density of infr