1,590 research outputs found

    Tadcaster Magnesian Limestone 3-D borehole interpretation and cross-sections study

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    This report was prepared under contract to the Environment Agency and describes the geology of the area surrounding Tadcaster in North Yorkshire. The work was commissioned to investigate the local geology and construct 3-D cross-sections from borehole and surface information. Approximately 1200 boreholes were utilised for the work and these ranged in depth from a few metres to 350m. Five cross-sections were constructed; three WSW-ENE trending sections and two NNW-SSE trending sections all to a depth of 250m below OD. In addition, a series of thematic maps were generated from the lithological component of the digital borehole data. Total superficial aquifer and superficial aquitard maps show how the lithological nature of the superficial sequence varies across the area. Rockhead elevation and superficial thickness maps indicate where the bedrock aquifers outcrop or are near to the ground surface. The east side of the Vale of York in the vicinity of Tadcaster is underlain by a sequence of Permian and Triassic rocks overlain in part by thick superficial deposits dating mainly from the last Ice-Age. The Permian rocks comprise two magnesian limestone aquifers separated by sequences of gypsum/anhydrite and gypsiferous mudstones. The overlying Triassic rocks comprise the major Sherwood Sandstone aquifer. The western part of the area consists of mainly exposed bedrock (Permian dolostone and dolomitic limestone), but the eastern side where the Sherwood Sandstone Group is present has a thick cover of superficial deposits including moraines, glacial lake deposits and alluvial deposits

    Determination of Li-6 -- He-4 interaction from multi-energy scattering data

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    We present the first successful potential model description of Li-6 -- He-4 scattering. The differential cross-sections for three energies and the vector analyzing powers for two energies were fitted by a single potential with energy dependent imaginary components. An essential ingredient is a set of Majorana terms in each component. The potential was determined using a recently developed direct data-to-potential inversion method which is a generalisation of the IP S-matrix-to-potential inversion algorithm. We discuss the problems related to this phenomenological approach, and discuss the relationship of our results to existing and future theories.Comment: 9 pages plain LaTeX, 6 postscript figue

    Magnetic field dependence of the temperature derivative of resistivity: a probe for distinguishing the effects of pseudogap and superconducting fluctuations in cuprates

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    We have studied the magnetic field dependence of the temperature derivative of the resistivity, dr(H,T)/dT, of a number of Y1-xCaxBa2(Cu1-yZny)3O7-d crystalline thin films over a wide range of sample compositions. From the analysis of the temperature derivative data we have been able to distinguish quite clearly between two characteristic temperature scales, (a) the onset of strong superconducting fluctuation temperature, Tscf and (b) the pseudogap temperature, TPG. Significantly different characteristic features of dr(H,T)/dT at Tscf and at TPG imply that Tscf and TPG have different physical origins.Comment: Submitted to Physica C (M2S-HTSC 2006 Proceedings

    Global Burden of Disease Attributable to Hypertension.

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    Deuteron -- α\alpha interaction by inversion of RGM S-matrix: determination of spin-orbit potential for spin-1 projectile

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    The iterative-perturbative (IP) procedure for S-matrix to potential inversion is applied to spin-one projectiles for the restricted case of vector spin-orbit interaction only. In order to evaluate this extension of IP inversion we have inverted the multi-channel RGM SljS_{lj} of Kanada et al for deuterons scattering from 4^4He with deuteron distortion and then compared the central components with those derived from RGM with spin set to zero. Attention is given to the question of how well the resulting potentials are established. Reliable spin-1 inversion is demonstrated. Results relating to inversion, to deuteron-nucleus interactions and to RGM are presented and suggest the range of nuclear interaction information which the procedure makes possible. Unusual non-locality and parity dependence effects are found; these are of possible relevance to generic properties of nuclear potentials.Comment: 15 pages LaTeX plus 6 postscript figure

    Disciplined Improvisation:Characteristics of inquiry in mindfulness-based teaching

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    Evidence for the effectiveness of mindfulness-based stress reduction (MBSR) and mindfulness-based cognitive therapy (MBCT) is rapidly growing as interest in this field expands. By contrast, there are few empirical analyses of the pedagogy of MBSR and MBCT. Development of the evidence base concerning the teaching of MBCT or MBSR would support the integrity of the approach in the context of rapid expansion. This paper describes an applied conversation analysis (CA) of the characteristics of inquiry in the MBSR and MBCT teaching process. Audio-recordings of three 8-week MBCT and MBSR classes, with 24, 12, and 6 participants, were transcribed and systematically examined. The study focused on the teacher-led interactive inquiry which takes place in each session after a guided meditation practice. The study describes and analyzes three practices within the inquiry process that can be identified in sequences of talk: turn-taking talk involving questions and reformulations; the development of participant skills in a particular way of describing experience; and talk that constructs intersubjective connection and affiliation within the group. CA enables fine-grained analysis of the interactional work of mindfulness-based inquiry. Inquiry is a process of disciplined improvisation which is both highly specific to the conditions of the moment it took place in and uses repeated and recognizable patterns of interaction

    Magneto-Transport Properties of Doped RuSr2_2GdCu2_2O8_8

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    RuSr2_2GdCu2_2O8_8, in which magnetic order and superconductivity coexist with TMagneticT_{Magnetic}\ggTcT_c, is a complex material which poses new and important questions to our understanding of the interplay between magnetic and superconducting (SC) order. Resistivity, Hall effect and thermopower measurements on sintered ceramic RuSr2_2GdCu2_2O8_8 are presented, together with results on a broad range of substituted analogues. The Hall effect and thermopower both show anomalous decreases below TMagneticT_{Magnetic} which may be explained within a simple two-band model by a transition from localized to more itinerant behavior in the RuO2_2 layer at TMagneticT_{Magnetic}.Comment: 10 pages, 7 figures, submitted to Phys. Rev. B., correspondence to [email protected]

    BECOOL: Ballooning eigensolver with COOL finite elements

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    An incompressible variational ideal ballooning mode equation is discretized with the COOL finite element discretization scheme using basis functions composed of variable order Legendre polynomials. This reduces the second order ordinary differential equation to a special block pentadiagonal matrix equation that is solved using an inverse vector iteration method. A benchmark test of BECOOL (Ballooning Eigensolver using COOL finite elements) with second order Legendre polynomials recovers precisely the eigenvalues computed by the VVBAL shooting code. Timing runs reveal the need to determine an optimal lower order case. Eigenvalue convergence runs show that cubic Legendre polynomials construct the optimal ballooning mode equation for intensive computations

    Superficial geology and hydrogeological domains between Durham and Darlington. Phase 2, (Durham North)

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    The North East Region’s Groundwater Modelling Strategy has identified the need for the development of a conceptual model for the Magnesian Limestone aquifer. In line with the Environment Agency R&D Technical Report W214 (Environment Agency Framework for Groundwater Resources Conceptual and Numerical Modelling), a scoping study was produced, that identified areas of uncertainty and work required for the development of the conceptual model. The purpose of this project is to give the Environment Agency (EA) a regional understanding of the geology and hydrogeology of the Magnesian Limestone and overlying superficial deposits in the North East Region, using information held by the British Geological Survey (BGS). This report contributes to the conceptual model and understanding of the Magnesian Limestone aquifer. There is uncertainty in the amount of recharge that the Magnesian Limestone receives from rainfall. The project is designed to gain a greater understanding of the geology of the superficial deposits and their hydrogeological properties. These are the key factors for the calculation of recharge to the Magnesian Limestone aquifer from rainfall. This element of the conceptual model is essential in understanding the potential water resource available within this aquifer

    Uncertainty in mapped geological boundaries held by a national geological survey: eliciting the geologists' tacit error model

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    It is generally accepted that geological line work, such as mapped boundaries, are uncertain for various reasons. It is difficult to quantify this uncertainty directly, because the investigation of error in a boundary at a single location may be costly and time consuming, and many such observations are needed to estimate an uncertainty model with confidence. However, it is recognized across many disciplines that experts generally have a tacit model of the uncertainty of information that they produce (interpretations, diagnoses, etc.) and formal methods exist to extract this model in usable form by elicitation. In this paper we report a trial in which uncertainty models for geological boundaries mapped by geologists of the British Geological Survey (BGS) in six geological scenarios were elicited from a group of five experienced BGS geologists. In five cases a consensus distribution was obtained, which reflected both the initial individually elicited distribution and a structured process of group discussion in which individuals revised their opinions. In a sixth case a consensus was not reached. This concerned a boundary between superficial deposits where the geometry of the contact is hard to visualize. The trial showed that the geologists' tacit model of uncertainty in mapped boundaries reflects factors in addition to the cartographic error usually treated by buffering line work or in written guidance on its application. It suggests that further application of elicitation, to scenarios at an appropriate level of generalization, could be useful to provide working error models for the application and interpretation of line work
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