1,905 research outputs found

    A small transitive family of continuous functions on the Cantor set

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    In this paper we show that, when we iteratively add Sacks reals to a model of ZFC we have for every two reals in the extension a continuous function defined in the ground model that maps one of the reals onto the other.Comment: 11 page

    Inventory of ammonia emissions from UK agriculture 2009

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    The National Ammonia Reduction Strategy Evaluation System (NARSES) model (spreadsheet version) was used to estimate ammonia (NH3) emissions from UK agriculture for the year 2009. Year-specific livestock numbers and fertiliser N use were added for 2009 and revised for previous years. The estimate for 2009 was 231.8 kt NH3, representing a 2.3 kt increase from the previously submitted estimate for 2008. Backward and forward projections using the 2009 model structure gave estimates of 317, 245 and 244 kt NH3 for the years 1990, 2010 and 2020, respectively. This inventory reports emission from livestock agriculture and from nitrogen fertilisers applied to agricultural land. There are a number of other minor sources reported as ‘agriculture’ in the total UK emission inventory, including horses not kept on agricultural holdings, emissions from composting and domestic fertiliser use

    Geology of Exeter and its environs

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    A 225 kmÂČ area around Exeter, described in this report, extends from the villages of Brampford Speke and Whimple in the north to Aylesbeare, Exminster and Woodbury in the south. It is underlain by Carboniferous, Permian, and Triassic solid formations and by a variety of Quaternary superficial deposits. The Namurian Crackington Formation comprises mainly tightly folded shales with subordinate sandstone interbeds. The Permian rocks consist of a lower, predominantly: breccia, sequence (Whipton Formation, Teignmouth Breccia, Monkerton Member) that thins and disappears northwards against a possibly fault-controlled ridge of Crackington Formation; the breccias are overlain by sandstones and mudstones (Dawlish Sandstone and Aylesbeare Mudstone). Volcanic rocks occur at the base of the Permian sequence and possibly within the Dawlish Sandstone. The latter splits into five alternating sandstone and mudstone members when traced northwards from Exeter into the Crediton Trough (an area of thick Permian sediments). The Aylesbeare Mudstone is divisible south of Aylesbeare into two members, the lower containing impersistent sandstones. It is overlain by the basal Triassic gravels (Budleigh Salterton Pebble Beds) which are in turn succeeded by the Otter Sandstone

    Mass customization of teaching and learning in organizations

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    In search of methods that improve the efficiency of teaching and training in organizations, several authors point out that mass customization (MC) is a principle that covers individual needs of knowledge and skills and, at the same time, limits the development costs of customized training to those of mass training. MC is proven and established in the economic sector, and shows high potential for continuing education, too. The paper explores this potential and proposes a multidisciplinary, pragmatic approach to teaching and training in organizations. The first section of the paper formulates four design principles of MC deduced from an examination of economics literature. The second section presents amitℱ, a frame for mass customized training, designed according to the principles presented in the first section. The evaluation results encourage the further development and use of mass customized training in continuing education, and offer suggestions for future research

    Impact of vertical mixing on sea surface pCO2 in temperate seasonally stratified shelf seas

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    A key parameter in determining the exchange of CO2 across the ocean-atmosphere interface is the sea surface partial pressure of carbon dioxide (pCO2). Temperate seasonally stratified shelf seas represent a significant sink for atmospheric CO2. Here an analytical model is used to quantify the impact of vertical mixing across the seasonal thermocline on pCO2. The model includes the impacts of the resultant dissolved inorganic carbon, heat, salt, and alkalinity fluxes on the solubility of CO2 and the effect of the inorganic carbon sink created by the primary production fuelled by the flux of limiting nutrient. The results indicate that diapycnal mixing drives a modest but continuous change in pCO2 of order 1–10 ”atm d−1. In quantifying the individual impacts of the fluxes of the different parameters, we find that the impact of the fluxes of DIC and nitrate fluxes dominate. In consequence, both the direction and magnitude of the change in pCO2 are strongly dependent on the C:N uptake ratio in primary production. While the smaller impacts of the heat and salt fluxes tend to compensate for each other at midshelf locations, the heat flux dominates close to the shelf break. The analysis highlights the importance of the accurate parameterization of the C:N uptake ratio, the surface-mixed layer depth, and the TKE dissipation rate within the seasonal thermocline in models to be used to predict the air-sea exchange of carbon dioxide in these regimes. The results implicate storms as key periods of pCO2 perturbation

    Nano-scale composition of commercial white powders for development of latent fingerprints on adhesives

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    This is the post-print version of the article - Copyright @ 2010 Elsevier.Titanium dioxide based powders are regularly used in the development of latent fingerprints on dark surfaces. For analysis of prints on adhesive tapes, the titanium dioxide can be suspended in a surfactant and used in the form of a powder suspension. Commercially available products, whilst having nominally similar composition, show varying levels of effectiveness of print development, with some powders adhering to the background as well as the print. X-ray fluorescence (XRF), analytical transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and laser particle sizing of the fingerprint powders show TiO2 particles with a surrounding coating, tens of nanometres thick, consisting of Al and Si rich material, with traces of sodium and sulphur. Such aluminosilicates are commonly used as anti-caking agents and to aid adhesion or functionality of some fingerprint powders; however, the morphology, thickness, coverage and composition of the aluminosilicates are the primary differences between the white powder formulations and could be related to variation in the efficacy of print development.This work is part funded by the Home Office Scientific Development Branch, UK

    Schlieren photography of current filaments in surface-related breakdown of silicon

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    Point mutations confer loss of ATP-induced human P2X7 receptor function

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    AbstractResidues considered essential for ATP binding to the human P2X7 receptor (hP2X7R) were investigated. HEK293 cells or Xenopus oocytes were transfected with wild-type or site-directed mutants of hP2X7R constructs and channel/pore activity measured in the presence of ATP or 2â€Č,3â€Č-O-(4-benzoylbenzoyl)-ATP (BzATP). Barium uptake and ethidium influx into HEK293 cells were abolished in cells expressing K193A and K311A mutants, and were partially reduced in cells expressing mutant P210A. K193A and K311A mutations also completely abolished responses to ATP and BzATP in Xenopus oocytes as measured by electrophysiology. These results indicate that K193 and K311 are essential residues in ATP binding in the hP2X7R

    Space Telescope and Optical Reverberation Mapping Project. XII. Broad-line Region Modeling of NGC 5548

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    We present geometric and dynamical modeling of the broad line region (BLR) for the multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The data set includes photometric and spectroscopic monitoring in the optical and ultraviolet, covering the HÎČ, C iv, and Lyα broad emission lines. We find an extended disk-like HÎČ BLR with a mixture of near-circular and outflowing gas trajectories, while the C iv and Lyα BLRs are much less extended and resemble shell-like structures. There is clear radial structure in the BLR, with C iv and Lyα emission arising at smaller radii than the HÎČ emission. Using the three lines, we make three independent black hole mass measurements, all of which are consistent. Combining these results gives a joint inference of . We examine the effect of using the V band instead of the UV continuum light curve on the results and find a size difference that is consistent with the measured UV–optical time lag, but the other structural and kinematic parameters remain unchanged, suggesting that the V band is a suitable proxy for the ionizing continuum when exploring the BLR structure and kinematics. Finally, we compare the HÎČ results to similar models of data obtained in 2008 when the active galactic nucleus was at a lower luminosity state. We find that the size of the emitting region increased during this time period, but the geometry and black hole mass remained unchanged, which confirms that the BLR kinematics suitably gauge the gravitational field of the central black hole

    Geology of Sheet SZ 19 (Hurn-Christchurch): part of 1:50 000 sheet 329 (Bournemouth)

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    The original geological survey of the area comprising sheet SZ 19 was made by H W Bristow and J Trimmer at the one-inch to one-mile scale (1:63 360) as parts of Old Sheets 15 and 16 published in 1856 and 1855 Series Geological respectively. The drift deposits were not represented on these maps. Clement Reid resurveyed the area on the six-inch to one-mile scale (1:10,560) in 1893, and his results were incorporated in New Series One-Inch Geological Sheet 329 (Bournemouth), published in 1895 in both Solid and Drift editions, and in the accompanying memoir (Reid, 1898). A second edition of this memoir was produced by H J 0 White, and was published in 1917. White re-examined much of the ground, but the published maps remained unaltered. In 1983 the Institute of Geological Sciences (now British Geological Survey) was commissioned by the Department of the Environment (contract PECD7/1/0103-149/82) to provide new 1:10,000 geological maps of the Poole-Bournemouth area. This contract comprises the survey of ten 1:10,000 sheets, and parts of four others, (Figure 1) over three years, to form a basis for the planning of urban and industrial development, and the safeguarding of mineral and water resources. During 1983, in the first phase of the contract, the four constituent quadrants of Sheet SZ 19 were mapped as follows, under the direction of R W Gallois, District Geologist: SZ 19 NW B J Williams; SZ 19 NE E C Freshney; SZ 19 SW E C Freshney; SZ 19 SE C R Bristow
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