Using Lidar Elevation Data to Develop a Topobathymetric Digital Elevation Model for Sub-Grid Inundation Modeling at Langley Research Center

Technological progression in light detection and ranging permits the production of highly detailed digital elevation models, which are useful in sub-grid hydrodynamic modeling applications. Sub-grid modeling technology is capable of incorporating these high-resolution lidar-derived elevation measurements into the conventional hydrodynamic modeling framework to resolve detailed topographic features for inclusion in a hydrological transport model for runoff simulations. The horizontal resolution and vertical accuracy of the digital elevation model is augmented via inclusion of these lidar elevation values on a nested 5-m sub-grid within each coarse computational grid cell. This aids in resolving ditches and overland drainage infrastructure at Langley Research Center to calculate runoff induced by the heavy precipitation often accompanied with tropical storm systems, such as Hurricane Irene (2011) and Hurricane Isabel (2003). Temporal comparisons of model results with a NASA tide gauge during Hurricane Irene yielded a good R-2 correlation of 0.97, and root mean squared error statistic of 0.079 m. A rigorous point-to-point comparison between model results and wrack line observations collected at several sites after Hurricane Irene revealed that when soil infiltration was not accounted for in the model, the mean difference between modeled and observed maximum water levels was approximately 10%. This difference was reduced to 2-5% when infiltration was considered in the model formulation, ultimately resulting in the sub-grid model more accurately predicting the horizontal maximum inundation extents within 1.0-8.5 m of flood sites surveyed. Finally, sea-level rise scenarios using Hurricane Isabel as a base case revealed future storm-induced inundation could extend 0.5-2.5 km inland corresponding to increases in mean sea level of 37.5-150 cm

Performance of structural concrete with recycled plastic waste as a partial replacement for sand

Environmental concerns arising from the over-dredging of sand have led to restrictions on its extraction across India, with direct economic impacts on concrete construction. A suitable environmentally friendly alternative to sand must be found to match the huge demand from the concrete construction industry. At the same time, waste plastic is rarely recycled in India, with as much as 40% left in landfill. The dumping of such materials which degrade at extremely low rates meaning they persist in the environment is a long-term environmental concern. To tackle both issues, it is proposed to process waste plastic to create a partial replacement for fine sand in a novel mix for structural concrete. In this paper eleven new concrete mixes are evaluated to study five plastic material compositions, three groups of particle sizes, three different aspect ratios, and two chemical treatments and establish an appropriate choice of material to act as partial replacement for sand. The results show that replacing 10% sand by volume with recycled plastic is a viable proposition that has the potential to save 820 million tonnes of sand every year. Through suitable mix design the structural performance of concrete with plastic waste can be maintained. This preliminary work was supported through funding from the British Council under the UKIERI (United Kingdom India Educational Research Initiative) programme for the project ‘Development of structural concrete with the help of plastic waste as partial replacement for sand’

Multispecies genetic objectives in spatial conservation planning.

The growing threats to biodiversity and global alteration of habitats and species distributions make it increasingly necessary to consider evolutionary patterns in conservation decision-making. Yet there is no clear-cut guidance on how genetic features can be incorporated into conservation planning processes, with multiple molecular markers and several genetic metrics for each marker type to choose from. Genetic patterns also differ between species, but the potential trade-offs amongst genetic objectives for multiple species in conservation planning are currently understudied. This study compares spatial conservation prioritizations derived from two metrics of both genetic diversity (nucleotide and haplotype diversity) and genetic isolation (private haplotypes and local genetic differentiation) for mitochondrial DNA for five marine species. The findings show that conservation plans based solely on habitat representation noticeably differ from those additionally including genetic data, with habitat-based conservation plans selecting fewer conservation priority areas. Furthermore, all four genetic metrics selected approximately similar conservation priority areas, which is likely a result of prioritizing genetic patterns across a genetically diverse array of species. Largely, the results suggest that multi-species genetic conservation objectives are vital to create protected area networks that appropriately preserve community-level evolutionary patterns. This article is protected by copyright. All rights reserved

Emerging applications of metal-organic frameworks and derivatives in solar cells: Recent advances and challenges

This is the final version. Available from Elsevier via the DOI in this record.Data availability: Data will be made available on request.The utilization of naturally existed energy is an indispensable solution to realise carbon neutral society in the future. Solar energy in the Sun is a tremendously abundant renewable and green energy resource which can provide more than enough energy to meet the whole world’s demand. The biggest challenge is to develop costeffective and durable materials to achieve efficient transformation of solar energy to electricity. As the most promising energy harvesting devices that based on the photovoltaic effect, solar cells can effectively transfer sunlight into electricity and the technologies have expanded rapidly over recent decades. Materials with optimal properties are the key to achieving efficient solar energy-driven performance for a variety of solar cells. Metalorganic frameworks (MOFs) and their derivatives, featured a great symbiosis of morphological, physicochemical and semiconducting properties that are difficult to achieve through the conventional materials, were intensively explored for energy storage and conversion applications in the past decade due to their intrinsic porous structures, tremendous inorganic-organic nature and fantastic diversity in functionalities. MOFs and derivatives based photovoltaic devices, especially solar cells, have demonstrated exceptional potential to enhance solar-toelectricity conversion performance with increased stability. In this review, the state-of-the-art progress on the applications of MOFs and their derivatives in a diverse range of solar cell devices including dye-sensitized solar cells, perovskite solar cells and organic solar cells is systematically documented. Important aspects on material compositions and structures, material synthesis strategies, device processing techniques, and photovoltaic performances of MOFs-based and MOF-derived materials used in solar cells are discussed and analyzed. The utilizations of MOFs and their derivatives as electrodes, photoactive materials, charge carriers and additives in different solar cells are highlighted. In addition, current challenges and perspectives on further development of MOF based materials for solar cell applications are also discussed.Royal Society (Charity)Leverhulme Trus

Extinction times in the subcritical stochastic SIS logistic epidemic

Many real epidemics of an infectious disease are not straightforwardly super- or sub-critical, and the understanding of epidemic models that exhibit such complexity has been identified as a priority for theoretical work. We provide insights into the near-critical regime by considering the stochastic SIS logistic epidemic, a well-known birth-and-death chain used to model the spread of an epidemic within a population of a given size $N$. We study the behaviour of the process as the population size $N$ tends to infinity. Our results cover the entire subcritical regime, including the "barely subcritical" regime, where the recovery rate exceeds the infection rate by an amount that tends to 0 as $N \to \infty$ but more slowly than $N^{-1/2}$. We derive precise asymptotics for the distribution of the extinction time and the total number of cases throughout the subcritical regime, give a detailed description of the course of the epidemic, and compare to numerical results for a range of parameter values. We hypothesise that features of the course of the epidemic will be seen in a wide class of other epidemic models, and we use real data to provide some tentative and preliminary support for this theory.Comment: Revised; 34 pages; 6 figure

Community based rehabilitation: a strategy for peace-building

BACKGROUND: Certain features of peace-building distinguish it from peacekeeping, and make it an appropriate strategy in dealing with vertical conflict and low intensity conflict. However, some theorists suggest that attempts, through peace-building, to impose liberal values upon non-democratic cultures are misguided and lack an ethical basis. DISCUSSION: We have been investigating the peace-building properties of community based approaches to disability in a number of countries. This paper describes the practice and impact of peace-building through Community Based Rehabilitation (CBR) strategies in the context of armed conflict. The ethical basis for peace-building through practical community initiatives is explored. A number of benefits and challenges to using CBR strategies for peace-building purposes are identified. SUMMARY: During post-conflict reconstruction, disability is a powerful emotive lever that can be used to mobilize cooperation between factions. We suggest that civil society, in contrast to state-level intervention, has a valuable role in reducing the risks of conflict through community initiatives

An investigation of psychological, social and environmental correlates of obesity and weight gain in young women

Objectives: This study explored the biological, psychological, social and environmental correlates of young women\u27s current weight and retrospective 2-year weight change. Methods: A total of 790 young women (mean age 26.8 years), sampled from the Australian Longitudinal Study on Women\u27s Health, provided self-reported data on their height and weight, sociodemographics and a range of biological, psychological, social and environmental variables. Results: Several variables from all domains (biological, psychological, social support and environmental) were correlated with higher body mass index, and less strongly greater 2-year weight change. Key correlates included the tendency to never put on weight, no matter what; self-efficacy for avoiding weight gain, and for healthy eating; attention paid to weight; family support and friends\u27 support/sabotage of physical activity/healthy eating; and perceived difficulty of taking the stairs rather than the elevator as part of the daily routine. Conclusions: Intervention strategies aimed at reducing weight gain and obesity may need to focus on social and environmental, as well as psychological factors; however, further research is necessary to confirm these findings given that a number of hypothesized associations were not observed.<br /

Electroweak Gauge-Boson Production at Small q_T: Infrared Safety from the Collinear Anomaly

Using methods from effective field theory, we develop a novel, systematic framework for the calculation of the cross sections for electroweak gauge-boson production at small and very small transverse momentum q_T, in which large logarithms of the scale ratio M_V/q_T are resummed to all orders. These cross sections receive logarithmically enhanced corrections from two sources: the running of the hard matching coefficient and the collinear factorization anomaly. The anomaly leads to the dynamical generation of a non-perturbative scale q_* ~ M_V e^{-const/\alpha_s(M_V)}, which protects the processes from receiving large long-distance hadronic contributions. Expanding the cross sections in either \alpha_s or q_T generates strongly divergent series, which must be resummed. As a by-product, we obtain an explicit non-perturbative expression for the intercept of the cross sections at q_T=0, including the normalization and first-order \alpha_s(q_*) correction. We perform a detailed numerical comparison of our predictions with the available data on the transverse-momentum distribution in Z-boson production at the Tevatron and LHC.Comment: 34 pages, 9 figure