746 research outputs found

    The impact of natural disasters on crime

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    This study addresses the following questions in the context of a developing coun- try. Do crimes increase following natural disasters? Does an upcoming election or the presence of a strong local media, which potentially increases the incentive of the gov- ernment to provide disaster relief, mitigate the eect of disasters on crime rates? I nd that crime rates tend to increase following moderate to big disasters. Furthermore, a higher pre-disaster growth of newspapers has a mitigating eect on the crime response to disasters. Elections also in uence the crime response to disasters. Crimes are more likely to rise following disasters in the years that are close to an election year.crime rate; natural disaster; role of media and elections; developing country

    Hydrophobic hydration driven self-assembly of Curcumin in water: Similarities to nucleation and growth under large metastability, and an analysis of water dynamics at heterogeneous surfaces

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    As the beneficial effects of curcumin have often been reported to be limited to its small concentrations, we have undertaken a study to find the aggregation properties of curcumin in water by varying the number of monomers. Our molecular dynamics simulation results show that the equilibrated structure is always an aggregated state with remarkable structural rearrangements as we vary the number of curcumin monomers from 4 to 16 monomers. We find that curcumin monomers form clusters in a very definite pattern where they tend to aggregate both in parallel and anti-parallel orientation of the phenyl rings, often seen in the formation of beta-sheet in proteins. A considerable enhancement in the population of parallel alignments is observed with increasing the system size from 12 to 16 curcumin monomers. Due to the prevalence of such parallel alignment for large system size, a more closely packed cluster is formed with maximum number of hydrophobic contacts. We also follow the pathway of cluster growth, in particular the transition from the initial segregated to the final aggregated state. We find the existence of a metastable structural intermediate involving a number of intermediate-sized clusters dispersed in the solution. The course of aggregation bears similarity to nucleation and growth in highly metastable state. The final aggregated form remains stable with total exclusion of water from its sequestered hydrophobic core. We also investigate water structure near the cluster surface along with their orientation. We find that water molecules form a distorted tetrahedral geometry in the 1st solvation layer of the cluster, interacting strongly with hydrophilic groups at the surface of curcumin. The dynamics of such quasi-bound water molecules near the surface of curcumin cluster is considerably slower than the bulk signifying a restricted motion as often found in protein hydration layer.Comment: 31 pages, 9 figure

    Sensitivity of Water Dynamics to Biologically Significant Surfaces of Monomeric Insulin: Role of Topology and Electrostatic Interactions

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    In addition to the biologically active monomer of the protein Insulin circulating in human blood, the molecule also exists in dimeric and hexameric forms that are used as storage. The Insulin monomer contains two distinct surfaces, namely the dimer forming surface (DFS) and the hexamer forming surface (HFS) that are specifically designed to facilitate the formation of the dimer and the hexamer, respectively. In order to characterize the structural and dynamical behaviour of interfacial water molecules near these two surfaces (DFS and HFS), we performed atomistic molecular dynamics simulations of Insulin with explicit water. Dynamical characterization reveals that the structural relaxation of the hydrogen bonds formed between the residues of DFS and the interfacial water molecules is faster than those formed between water and that of the HFS. Furthermore, the residence times of water molecules in the protein hydration layer for both the DFS and HFS are found to be significantly higher than those for some of the other proteins studied so far, such as HP-36 and lysozyme. The surface topography and the arrangement of amino acid residues work together to organize the water molecules in the hydration layer in order to provide them with a preferred orientation. HFS having a large polar solvent accessible surface area and a convex extensive nonpolar region, drives the surrounding water molecules to acquire predominantly a clathrate-like structure. In contrast, near the DFS, the surrounding water molecules acquire an inverted orientation owing to the flat curvature of hydrophobic surface and interrupted hydrophilic residual alignment. We have followed escape trajectory of several such quasi-bound water molecules from both the surfaces and constructed free energy surfaces of these water molecules.These free energy surfaces reveal the differences between the two hydration layers.Comment: 34 pages, 10 figure

    Environmental regulation and development : a cross-country empirical analysis

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    The authors develop comparative indices of environmental policy and performance for 31 countries using a quantified analysis of reports prepared for the United Nations Conference on Environmental and Development. In cross-country regressions, they find a very strong, continuous association between their indicators and national income per capita, particularly when adjusted for purchasing power parity. Their results suggest a characteristic progression in development. Poor agrarian economies focus first on natural resource protection. With increased urbanization and industrialization, countries move from initial regulation of water pollution to air pollution control. The authors highlight the importance of institutional development. Environmental regulation is more advanced in developing countries with relatively secure property rights, effective legal and judicial systems, and efficient public administration.Public Health Promotion,Environmental Economics&Policies,Health Economics&Finance,Agricultural Research,Economic Theory&Research,Environmental Economics&Policies,Health Economics&Finance,Agricultural Research,Economic Theory&Research,Environmental Governance

    Productivity Puzzling: A Study on Recent Behaviour of UK and Bangladesh

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    Productivity is a multi-faceted concept; no single definition can holistically describe it. However, in the simplest form, productivity signifies the ratio between the input and output. In achieving sustained economic growth of a country, increased productivity remains as the key component. Productivity signifies a continual striving towards the economically most efficient mode of production of goods, commodities, and services needed by a society. Prior to the mid-1980s, labour productivity growth was a useful barometer of the world economy: it was low when the economy was depressed and high when it was booming. In many larger advanced economies like UK labour productivity growth slowed sharply and remained subdued for years after the credit crisis of 2007/08. After the early 1980s productivity issues were considered as a priority area for action in Bangladesh: a small economic country, but Productivity has slowed down again significantly during the last decade (2001-2012) because of some reasons. In this paper, we tried to find out the reasons behind for productivity puzzling in UK as well as in Bangladesh. For  UK productivity puzzle, this study considered that workforce composition, lower business investment, flexibility of labour market, Impaired resource allocation, and public sector productivity were the major factors that might have caused productivity to fall and in Bangladesh, insignificant role of allocative efficiency of resources within industry, poor performing public sector, inadequate public sector investment, labor union, firm size and productivity are inversely related were the major factors that might had caused low productivity. In light of these findings, it is found that there is a similarity between productivity puzzling factor of UK and Bangladesh. Performance and investment in public sector and improper resource allocation are common productivity puzzling factor for both the countries. Keywords: Productivity Puzzling, UK, Banglades
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