4,347 research outputs found

    Massless monopoles and the moduli space approximation

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    We investigate the applicability of the moduli space approximation in theories with unbroken non-Abelian gauge symmetries. Such theories have massless magnetic monopoles that are manifested at the classical level as clouds of non-Abelian field surrounding one or more massive monopoles. Using an SO(5) example with one massive and one massless monopole, we compare the predictions of the moduli space approximation with the results of a numerical solution of the full field equations. We find that the two diverge when the cloud velocity becomes of order unity. After this time the cloud profile approximates a spherical wavefront moving at the speed of light. In the region well behind this wavefront the moduli space approximation continues to give a good approximation to the fields. We therefore expect it to provide a good description of the motion of the massive monopoles and of the transfer of energy between the massive and massless monopoles.Comment: 18 pages, 5 figure

    A user guide for the GeoSure Extra : Debris Flow Susceptibility Model for Great Britain (Version 6.0)

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    This report is the published product of a study by the British Geological Survey (BGS) to produce a national scale Debris Flow Susceptibility Map for Great Britain. It builds on research BGS has conducted over the past decade investigating debris flows and extends the work conducted by Harrison et al., (2006) as part of the Transport Scotland Scottish Road Network Landslides Study (Winter et al., 2005, Winter et al., 2009). The Debris Flow Susceptibility Model provides information on the potential of the ground, at a given location, to form a debris flow. It is based on a combination of digital geological, hydrogeological and topographic data. The methodology develops an additional dimension to the BGS GeoSure Landslides surface layer (Dashwood et al., 2014) and is designed for users interested specifically in debris flow susceptibility. This document outlines the background to why the dataset was created, its potential uses and gives a brief description of the GIS raster file. Technical information regarding the GIS and how the data were created is described and advice is provided on using the dataset

    Creating a Debris Flow Susceptibility Model for Great Britain: a GIS Based Approach

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    The term debris flow refers to the rapid downslope flow of poorly-sorted debris mixed with water (Ballantyne, 2004). Debris flows are described by (Hungr et al., 2014) as: “very rapid to extremely rapid surging flow of saturated debris in a steep channel. Strong entrainment of material and water from the flow path”. They are a widespread phenomenon in mountainous terrain and are distinct from other types of landslides as they can occur periodically on established paths, usually gullies and first- or second-order drainage channels. Debris flows in Great Britain are most commonly found in upland Scotland but also in parts of Wales and the Lake District

    An Index Theorem for Domain Walls in Supersymmetric Gauge Theories

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    The supersymmetric abelian Higgs model with N scalar fields admits multiple domain wall solutions. We perform a Callias-type index calculation to determine the number of zero modes of this soliton. We confirm that the most general domain wall has 2(N-1) zero modes, which can be interpreted as the positions and phases of (N-1) constituent domain walls. This implies the existence of moduli for a D-string interpolating between N D5-branes in IIB string theory.Comment: 9 pages, REVTeX4; v2: reference adde

    Pregnancy After “a Choice to Drink”: Meanings of Autonomy in England's Policies on Fetal Alcohol Spectrum Disorder

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    There are few areas of social life where the paradox of autonomy is played out more continually than with pregnancy. This chapter considers meanings ascribed to autonomy through discussing an analysis of policy documents about fetal alcohol spectrum disorder (FASD) published by health authorities in England. These documents justify a suite of health interventions presented as necessary to prevent this disorder in those yet to be born and to address the health and care needs of those who may be diagnosed with FASD after birth. The prevention aspect of the policy framework and its concepts of autonomy in pregnancy are focused on. Context is provided through an account of scholarship detailing ways the “choice to drink” became compromised since the “discovery” of Fetal Alcohol syndrome (FAS) in the early 1970s. Conceptualizations of autonomy associated with what the chapter terms a “post-choice policy framework” are then detailed, with attention paid especially to what policies say about providing and collecting information. It is argued that concepts of autonomy are modified, as autonomy for pregnant women both appears and disappears as a consideration. Either way, autonomy is given a meaning that makes its existence contingent on professional influence, diminishing space for maternal judgement

    Nano encapsulation of Drug-loaded Lipid by Temperature induced Phase Transition

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    Pluronic nanoparticles (NPs) were prepared by means of a temperature-induced phase transition in the mixture composed of Pluronic F-68 and liquid Tween 80/soybean oil containing model drugs such as orlistat, caffeine, and ibuprofen sodium salt. Liquid soybean oil/Tween 80 was used as a solubilizer for model drugs, and Pluronic F-68 was the polymer that stabilizes liquid soybean oil/Tween 80 containing model drugs. Field-emission scanning electron microscopy and particle size analyzer were used to observe the morphology and size distribution of the prepared NPs. X-ray diffractometer was used to understand relationship between the crystalline state of the model drug and its solubility in the aqueous media. To observe the feasibility of Pluronic NPs as a drug delivery system, the release pattern of model drugs was observed

    Nano encapsulation of Drug-loaded Lipid by Temperature induced Phase Transition

    Get PDF
    Pluronic nanoparticles (NPs) were prepared by means of a temperature-induced phase transition in the mixture composed of Pluronic F-68 and liquid Tween 80/soybean oil containing model drugs such as orlistat, caffeine, and ibuprofen sodium salt. Liquid soybean oil/Tween 80 was used as a solubilizer for model drugs, and Pluronic F-68 was the polymer that stabilizes liquid soybean oil/Tween 80 containing model drugs. Field-emission scanning electron microscopy and particle size analyzer were used to observe the morphology and size distribution of the prepared NPs. X-ray diffractometer was used to understand relationship between the crystalline state of the model drug and its solubility in the aqueous media. To observe the feasibility of Pluronic NPs as a drug delivery system, the release pattern of model drugs was observed

    SU(2) Calorons and Magnetic Monopoles

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    We investigate the self-dual Yang-Mills gauge configurations on R3Ă—S1R^3\times S^1 when the gauge symmetry SU(2) is broken to U(1) by the Wilson loop. We construct the explicit field configuration for a single instanton by the Nahm method and show that an instanton is composed of two self-dual monopoles of opposite magnetic charge. We normalize the moduli space metric of an instanton and study various limits of the field configuration and its moduli space metric.Comment: 17 pages, RevTex, 1 Figur
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