12,513 research outputs found

    International Lattice Data Grid: Turn on, plug in,and download

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    In the beginning there was the internet, then came the world wide web, and now there is the grid. In the future perhaps there will be the cloud. In the age of persistent, pervasive, and pandemic networks I review how the lattice QCD community embraced the open source paradigm for both code and data whilst adopting the emerging grid technologies, and why having your data persistently accessible via standardized protocols and services might be a good idea.Comment: 8 pages, 1 figur

    The employment benefits of organic farming

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    Organic farming in the UK provides a range of economic and social benefi ts. In particular, it provides 32% more jobs per farm than equivalent non-organic farms. These new findings are based on the fi rst national survey of employment on UK organic farms, carried out by the University of Essex for the Soil Association. Organic farming is helping to reverse the decline in the UK’s agricultural workforce, which has fallen by 80% in the last 50 years. In contrast to the ageing overall farming population, organic farmers are, on average, seven years younger than their non-organic counterparts. Organic farmers are also three times more likely to be engaged in business innovations activities, such as direct marketing and on-farm processing. If all UK farmers adopted organic farming, it would produce an additional 93,000 on-farm jobs. These findings have significant implications for developing countries where a skilled agricultural workforce is vital to safeguard livelihoods and ensure global food security

    Phase Diagrams of Quasispecies Theory with Recombination and Horizontal Gene Transfer

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    We consider how transfer of genetic information between individuals influences the phase diagram and mean fitness of both the Eigen and the parallel, or Crow-Kimura, models of evolution. In the absence of genetic transfer, these physical models of evolution consider the replication and point mutation of the genomes of independent individuals in a large population. A phase transition occurs, such that below a critical mutation rate an identifiable quasispecies forms. We generalize these models of quasispecies evolution to include horizontal gene transfer. We show how transfer of genetic information changes the phase diagram and mean fitness and introduces metastability in quasispecies theory, via an analytic field theoretic mapping.Comment: 5 pages, 1 figure, to appear in Physics Review Letter

    Ionospheric and magnetospheric plasmapauses'

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    During August 1972, Explorer 45 orbiting near the equatorial plane with an apogee of about 5.2 R sub e traversed magnetic field lines in close proximity to those simultaneously traversed by the topside ionospheric satellite ISIS 2 near dusk in the L range 2-5.4. The locations of the Explorer 45 plasmapause crossings during this month were compared to the latitudinal decreases of the H(+) density observed on ISIS 2 near the same magnetic field lines. The equatorially determined plasmapause field lines typically passed through or poleward of the minimum of the ionospheric light ion trough, with coincident satellite passes occurring for which the L separation between the plasmapause and trough field lines was between 1 and 2. Vertical flows of the H(+) ions in the light ion trough as detected by the magnetic ion mass spectrometer on ISIS were directed upward with velocities between 1 and 2 kilometers/sec near dusk on these passes. These velocities decreased to lower values on the low latitude side of the H(+) trough but did not show any noticeable change across the field lines corresponding to the magnetospheric plasmapause

    Benefit-Cost Analysis: 1933-1985

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