16 research outputs found
The Nuts and Bolts of Einstein-Maxwell Solutions
We find new non-supersymmetric solutions of five-dimensional ungauged
supergravity coupled to two vector multiplets. The solutions are regular,
horizonless and have the same asymptotic charges as non-extremal charged black
holes. An essential ingredient in our construction is a four-dimensional
Euclidean base which is a solution to Einstein-Maxwell equations. We construct
stationary solutions based on the Euclidean dyonic Reissner-Nordstrom black
hole as well as a six-parameter family with a dyonic Kerr-Newman-NUT base.
These solutions can be viewed as compactifications of eleven-dimensional
supergravity on a six-torus and we discuss their brane interpretation.Comment: 29 pages, 3 figure
The Confrontation between General Relativity and Experiment
The status of experimental tests of general relativity and of theoretical
frameworks for analysing them is reviewed. Einstein's equivalence principle
(EEP) is well supported by experiments such as the Eotvos experiment, tests of
special relativity, and the gravitational redshift experiment. Future tests of
EEP and of the inverse square law are searching for new interactions arising
from unification or quantum gravity. Tests of general relativity at the
post-Newtonian level have reached high precision, including the light
deflection, the Shapiro time delay, the perihelion advance of Mercury, and the
Nordtvedt effect in lunar motion. Gravitational-wave damping has been detected
in an amount that agrees with general relativity to better than half a percent
using the Hulse-Taylor binary pulsar, and other binary pulsar systems have
yielded other tests, especially of strong-field effects. When direct
observation of gravitational radiation from astrophysical sources begins, new
tests of general relativity will be possible.Comment: 89 pages, 8 figures; an update of the Living Review article
originally published in 2001; final published version incorporating referees'
suggestion
Delivering exceptionally safe transitions of care to older people : a qualitative study of multidisciplinary staff perspectives
Background Transitions of care are often risky, particularly for older people, and shorter hospital stays mean that patients can go home with ongoing care needs. Most previous research has focused on fundamental system flaws, however, care generally goes right far more often than it goes wrong. We explored staff perceptions of how high performing general practice and hospital specialty teams deliver safe transitional care to older people as they transition from hospital to home. Methods We conducted a qualitative study in six general practices and four hospital specialties that demonstrated exceptionally low or reducing readmission rates over time. Data were also collected across four community teams that worked into or with these high-performing teams. In total, 157 multidisciplinary staff participated in semi-structured focus groups or interviews and 9 meetings relating to discharge were observed. A pen portrait approach was used to explore how teams across a variety of different contexts support successful transitions and overcome challenges faced in their daily roles. Results Across healthcare contexts, staff perceived three key themes to facilitate safe transitions of care: knowing the patient, knowing each other, and bridging gaps in the system. Transitions appeared to be safest when all three themes were in place. However, staff faced various challenges in doing these three things particularly when crossing boundaries between settings. Due to pressures and constraints, staff generally felt they were only able to attempt to overcome these challenges when delivering care to patients with particularly complex transitional care needs. Conclusions It is hypothesised that exceptionally safe transitions of care may be delivered to patients who have particularly complex health and/or social care needs. In these situations, staff attempt to know the patient, they exploit existing relationships across care settings, and act to bridge gaps in the system. Systematically reinforcing such enablers may improve the delivery of safe transitional care to a wider range of patients. Trial registration The study was registered on the UK Clinical Research Network Study Portfolio (references 35272 and 36174)