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Independent reporting sonographers-could other countries follow the UK's lead 2017
The rapid growth in the use of ultrasound as a diagnostic imaging technology over the past 40 years, has led to a demand for a workforce with the appropriate skills to perform and interpret the scans. For many years, the majority of ultrasound examinations in the United Kingdom (UK), both obstetric and non-obstetric, have been performed by radiographers who have undergone postgraduate training. These ‘sonographers’ scan, interpret and report their own examinations. Today, sonographer-led ultrasound services are essential and well established. The second largest professional group performing ultrasound in the UK comprises radiologists. Other groups including midwives, obstetricians, emergency physicians and abdominal aortic aneurysm screening technicians, also contribute to services. This model is successful yet it appears to be unique1. No other country relies so heavily on sonographers. Throughout mainland Europe, physicians and general practitioners perform a significant proportion of ultrasound examinations, having undergone very variable levels of training in ultrasound. Alternatively, sonographers may perform the scans but reporting remains the domain of the overseeing medical staff. For example, in countries such as Australia, Canada and the United States, ultrasound might be performed by sonographers but there is little evidence of independent reporting. However, the escalating need for ultrasound services is now causing some teams, particularly from Australia and some mainland European countries, to start focusing their attention on the UK model as a possible solution to meet demand
Frustration in Finite Density QCD
We present a detailed analysis of the QCD partition function in the Grand
Canonical formalism. Using the fugacity expansion we find evidence for
numerical instabilities in the standard evaluation of its coefficients. We
discuss the origin of this problem and propose an issue to it. The correct
analysis shows no evidence for a discontinuity in the baryonic density in the
strong coupling limit. The moderate optimism that was inspired by the Grand
Canonical Partition Function calculations in the last years has to be
considered ill-founded.Comment: 9 pages, 6 Postscript figures; some comments adde
Charge Symmetry Violation Effects in Pion Scattering off the Deuteron
We discuss the theoretical and experimental situations for charge symmetry
violation (CSV) effects in the elastic scattering of pi+ and pi- on deuterium
(D) and 3He/3H. Accurate comparison of data for both types of targets provides
evidence for the presence of CSV effects. While there are indications of a CSV
effect in deuterium, it is much more pronounced in the case of 3He/3H. We
provide a description of the CSV effect on the deuteron in terms of single- and
double- scattering amplitudes. The Delta-mass splitting is taken into account.
Theoretical predictions are compared with existing experimental data for pi-d
scattering; a future article will speak to the pi-three nucleon case.Comment: 16 pages of RevTeX, 7 postscript figure
Elastic Scattering of Pions From the Three-nucleon System
We examine the scattering of charged pions from the trinucleon system at a
pion energy of 180 MeV. The motivation for this study is the structure seen in
the experimental angular distribution of back-angle scattering for pi+ 3He and
pi- 3H but for neither pi- 3He nor pi+ 3H. We consider the addition of a double
spin flip term to an optical model treatment and find that, though the
contribution of this term is non-negligible at large angles for pi+ 3He and pi-
3H, it does not reproduce the structure seen in the experiment.Comment: 15 pages + 5 figure
Mesoscopic Phase Fluctuations: General Phenomenon in Condensed Matter
General conditions for the occurrence of mesoscopic phase fluctuations in
condensed matter are considered. The description of different thermodynamic
phases, which coexist as a mixture of mesoscopically separated regions, is
based on the {\it theory of heterophase fluctuations}. The spaces of states,
typical of the related phases, are characterized by {\it weighted Hilbert
spaces}. Several models illustrate the main features of heterophase condensed
matter.Comment: 23 pages, Latex, no figure
Three and Two Colours Finite Density QCD at Strong Coupling: A New Look
Simulations in finite density, beta=0 lattice QCD by means of the
Monomer-Dimer-Polymer algorithm show a signal of first order transition at
finite temporal size. This behaviour agrees with predictions of the mean field
approximation, but is difficult to reconcile with infinite mass analytical
solution. The MDP simulations are considered in detail and severe convergence
problems are found for the SU(3) gauge group, in a wide region of chemical
potential. Simulations of SU(2) model show discrepancies with MDP results as
well.Comment: 18 pages, 9 figures, to appear in Nucl. Phys.
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