1,334 research outputs found
Minimum intervention children's dentistry - the starting point for a lifetime of oral health
Child-friendly minimum intervention dentistry (MID) dominates modern thinking and practice around delivery of oral care for children. It is an enormous challenge for our profession to move away from the narrow focus of a mechanistic, cavity-orientated surgical approach for managing dental caries to one which embraces new strategies for caries prevention and management, delivered in the context of a partnership with children, families and other adults involved in the child's life environment. It is also time for a shift in the orientation of dentistry towards 'patient self-care' becoming a core goal of dental care, where dentists help their patients assume responsibility for achieving and maintaining their own oral health, and that of their children. Holistic care, which improves oral health and maximises ability to maintain oral health, should be regarded with the same importance and rewarded with a similar level of remuneration as 'traditional operative dentistry'. This paper gives an overview of a model of care involving the principles of this new approach, and the application of MID in clinical practice for primary teeth
Zero Modes of Rotationally Symmetric Generalized Vortices and Vortex Scattering
Zero modes of rotationally symmetric vortices in a hierarchy of generalized
Abelian Higgs models are studied. Under the finite-energy and the smoothness
condition, it is shown, that in all models, self-dual vortices superimposed
at the origin have modes. The relevance of these modes for vortex
scattering is discussed, first in the context of the slow-motion approximation.
Then a corresponding Cauchy problem for an all head-on collision of
vortices is formulated. It is shown that the solution of this Cauchy problem
has a symmetry.Comment: 12 pages. late
Statistical Mechanics of Charged Particles in Einstein-Maxwell-Scalar Theory
We consider an -body system of charged particle coupled to gravitational,
electromagnetic, and scalar fields. The metric on moduli space for the system
can be considered if a relation among the charges and mass is satisfied, which
includes the BPS relation for monopoles and the extreme condition for charged
black holes. Using the metric on moduli space in the long distance
approximation, we study the statistical mechanics of the charged particles at
low velocities. The partition function is evaluated as the leading order of the
large expansion, where is the spatial dimension of the system and will
be substituted finally as .Comment: 11 pages, RevTeX3.
New Integrable Sectors in Skyrme and 4-dimensional CP^n Model
The application of a weak integrability concept to the Skyrme and
models in 4 dimensions is investigated. A new integrable subsystem of the
Skyrme model, allowing also for non-holomorphic solutions, is derived. This
procedure can be applied to the massive Skyrme model, as well. Moreover, an
example of a family of chiral Lagrangians providing exact, finite energy
Skyrme-like solitons with arbitrary value of the topological charge, is given.
In the case of models a tower of integrable subsystems is obtained. In
particular, in (2+1) dimensions a one-to-one correspondence between the
standard integrable submodel and the BPS sector is proved. Additionally, it is
shown that weak integrable submodels allow also for non-BPS solutions.
Geometric as well as algebraic interpretations of the integrability conditions
are also given.Comment: 23 page
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
Electrically Charged Sphalerons
We investigate the possibility that the Higgs sector of the Weinberg-Salam
model admits the existence of electrically charged, sphaleron states. Evidence
is provided through an asymptotic and numerical perturbative analysis about the
uncharged sphaleron. By introducing a toy model in two dimensions we
demonstrate that such electrically charged, unstable states can exist.
Crucially, they can have a comparable mass to their uncharged counterparts and
so may also play a role in electroweak baryogenesis, by opening up new channels
for baryon number violating processes.Comment: 12 pages, 4 Postscript figure
Dynamics of BPS Dyons: Effective Field Theory Approach
Based on a detailed analysis of nonlinear field equations of the SU(2)
Yang-Mills-Higgs system, we obtain the effective field theory describing
low-energy interaction of BPS dyons and massless particles (i.e., photons and
Higgs particles). Our effective theory manifests electromagnetic duality and
spontaneously broken scale symmetry, and reproduces the multimonopole moduli
space dynamics of Manton in a suitable limit. Also given is a generalization of
our approach to the case of BPS dyons in a gauge theory with an arbitrary gauge
group that is maximally broken.Comment: 48 pages, uses revte
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