4,405 research outputs found
Massless monopoles and the moduli space approximation
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)
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
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
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
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
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
We investigate the self-dual Yang-Mills gauge configurations on 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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