2,407 research outputs found
A Mixed-Methods, Randomized, Controlled Feasibility Trial to Inform the Design of a Phase III Trial to Test the Effect of the Handheld Fan on Physical Activity and Carer Anxiety in Patients with Refractory Breathlessness
© 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved. Context The handheld fan is an inexpensive and safe way to provide facial airflow, which may reduce the sensation of chronic refractory breathlessness, a frequently encountered symptom. Objectives To test the feasibility of developing an adequately powered, multicenter, multinational randomized controlled trial comparing the efficacy of a handheld fan and exercise advice with advice alone in increasing activity in people with chronic refractory breathlessness from a variety of medical conditions, measuring recruitment rates; data quality; and potential primary outcome measures. Methods This was a Phase II, multisite, international, parallel, nonblinded, mixed-methods randomized controlled trial. Participants were centrally randomized to fan or control. All received breathlessness self-management/exercise advice and were followed up weekly for four weeks. Participants/carers were invited to participate in a semistructured interview at the study's conclusion. Results Ninety-seven people were screened, 49 randomized (mean age 68 years; 49% men), and 43 completed the study. Site recruitment varied from 0.25 to 3.3/month and screening:randomization from 1.1:1 to 8.5:1. There were few missing data except for the Chronic Obstructive Pulmonary Disease Self-Efficacy Scale (two-thirds of data missing). No harms were observed. Three interview themes included 1) a fan is a helpful self-management strategy, 2) a fan aids recovery, and 3) a symptom control trial was welcome. Conclusion A definitive, multisite trial to study the use of the handheld fan as part of self-management of chronic refractory breathlessness is feasible. Participants found the fan useful. However, the value of information for changing practice or policy is unlikely to justify the expense of such a trial, given perceived benefits, the minimal costs, and an absence of harms demonstrated in this study
Topographic and hydrodynamic controls on barrier retreat and preservation: An example from Dogger Bank, North Sea
Barrier retreat can occur due to in-place drowning, overstepping or rollover, depending on the interplay of controls such as sea-level rise, sediment supply, coastal hydrodynamic regime and topography. Offshore sedimentary archives of barriers active during rapid Holocene sea-level rise provide important records of marine transgression, which are vital analogues to support appropriate mitigation strategies for future coastal realignment under projected relative sea-level rise scenarios. This study analyses the sedimentary archive at Dogger Bank, which is a formerly-glaciated area in the North Sea. Dogger Bank experienced marine transgression due to Early Holocene rapid relative sea-level rise. An integrated dataset of vibrocores and high-resolution seismic reflection data permits a stratigraphic framework to be established, which reveals the buried coastal geomorphology of the southern Dogger Bank for the first time. A transgressive stratigraphy was identified, comprising a topographically complicated basal glacial and terrestrial succession, overlain by two phases of barrier and tidal mudflat deposition, prior to shallow marine sedimentation. Barrier phase A was a recurved barrier drowned in place, and discontinuously overstepped to barrier phase B, which experienced continuous overstepping. By linking barrier elevations to relative sea-level curves, the timing of each barrier phase was established. Both barrier phases retreated during periods of rapid sea-level rise with abundant sediment supply. Coastal hydrodynamics (increasing wave energy) and antecedent topography with spatially variable accommodation are suggested to be the main reason for differing retreat mechanisms, rather than the rate of sea-level rise. Antecedent coastal geomorphology plays a critical role in erosional and depositional patterns during transgression, and therefore on the timing, rate and location of marine inundation, which needs to be included in models that aim to forecast hazards in coastal areas
The future of midlatitude cyclones
This is the final version. Available from the publisher via the DOI in this record.Purpose of Review This review brings together recent research on the structure, characteristics, dynamics, and impacts of
extratropical cyclones in the future. It draws on research using idealized models and complex climate simulations, to evaluate
what is known and unknown about these future changes.
Recent Findings There are interacting processes that contribute to the uncertainties in future extratropical cyclone changes, e.g.,
changes in the horizontal and vertical structure of the atmosphere and increasing moisture content due to rising temperatures.
Summary While precipitation intensity will most likely increase, along with associated increased latent heating, it is unclear to
what extent and for which particular climate conditions this will feedback to increase the intensity of the cyclones. Future research
could focus on bridging the gap between idealized models and complex climate models, as well as better understanding of the
regional impacts of future changes in extratropical cyclones.Natural Environment Research Council (NERC
How effective is stretching in maintaining range of movement for children with cerebral palsy?
YesBackground: Cerebral Palsy (CP) is the most common childhood disorder affecting four percent of children born in the UK. It is common for children with CP to have reduced range of movement (ROM) due to spasticity and contractures. Stretching is commonly used in physiotherapy programmes to manage this.
Aim: This critical review aims to evaluate the evidence base behind the use of stretching for children with CP.
Methods: A systematic literature search of AMED, CINAHL, MEDLINE and Cochrane Library Trials was conducted. Returned searches were assessed against strict criteria according to a predefined PICOS (Population, Intervention, Comparison, Outcome, Study). These studies were then critically appraised to assess the validity, reliability and clinical relevance.
Findings: There is evidence supporting the use of stretching in children with CP. However there is also some evidence to suggest very little or no positive change. All of the included studies have methodological limitations, which questions the validity of the results.
Conclusions/Recommendations: The research suggests some positive outcomes for the use of stretching in CP, studies that did not find positive outcomes found no adverse effects; however further research in the area is required to validate the effectiveness of stretching to maintain ROM in children with CP
‘Small Project, Big Difference’: capacity building through a national volunteering fund : An Evaluation of The Department of Health’s Health and Social Care Volunteering Fund
This article reports the findings of a mixed methods evaluation study on the impact of a national fund to support volunteering as a mechanism to achieve health and social goals, within the Department of Health’s Volunteering Fund Programme (HSCVF). This paper adds understanding of the mechanisms through which government organisations can build VSCE organisational capacity to support volunteers. Firstly, the programme increased capacity via resource mobilisation to enhance volunteer recruitment, secondly it strengthened voluntary, community and social enterprise (VCSE) organisations through linkages and finally the programme supported development and learning. The HSCVF impacted upon both volunteering projects and host organisations to produce a range of positive outcomes that were particularly marked in smaller organisations: ‘small project, big difference’. Successful community capacity building can result from programmes such as HSCVF, with this paper contributing to the evidence base by detailing the processes through which this occurred
Perturbing the superconducting planes in CeCoIn5 by Sn substitution
In contrast to substitution on the Co or Ce site, Sn substitution has a remarkably strong effect on superconductivity in CeCoIn5-xSnx, with T-c -> 0 beyond only similar to 3.6% Sn. Instead of being randomly distributed on in-plane and out-of-plane In sites, extended x-ray absorption fine structure measurements show the Sn atoms preferentially substitute within the Ce-In plane. This result highlights the importance of the In(1) site to impurity scattering and clearly demonstrates the two-dimensional nature of superconductivity in CeCoIn5.95
Are autistic traits measured equivalently in individuals with and without an Autism Spectrum Disorder?:An invariance analysis of the Autism Spectrum Quotient Short Form
It is common to administer measures of autistic traits to those without autism spectrum disorders (ASDs) with, for example, the aim of understanding autistic personality characteristics in non-autistic individuals. Little research has examined the extent to which measures of autistic traits actually measure the same traits in the same way across those with and without an ASD. We addressed this question using a multi-group confirmatory factor invariance analysis of the Autism Quotient Short Form (AQ-S: Hoekstra et al. in J Autism Dev Disord 41(5):589-596, 2011) across those with (n = 148) and without (n = 168) ASD. Metric variance (equality of factor loadings), but not scalar invariance (equality of thresholds), held suggesting that the AQ-S measures the same latent traits in both groups, but with a bias in the manner in which trait levels are estimated. We, therefore, argue that the AQ-S can be used to investigate possible causes and consequences of autistic traits in both groups separately, but caution is due when combining or comparing levels of autistic traits across the two group
A de Sitter Hoedown
Rotating black holes in de Sitter space are known to have interesting limits
where the temperatures of the black hole and cosmological horizon are equal. We
give a complete description of the thermal phase structure of all allowed
rotating black hole configurations. Only one configuration, the rotating Nariai
limit, has the black hole and cosmological horizons both in thermal and
rotational equilibrium, in that both the temperatures and angular velocities of
the two horizons coincide. The thermal evolution of the spacetime is shown to
lead to the pure de Sitter spacetime, which is the most entropic configuration.
We then provide a comprehensive study of the wave equation for a massless
scalar in the rotating Nariai geometry. The absorption cross section at the
black hole horizon is computed and a condition is found for when the scattering
becomes superradiant. The boundary-to-boundary correlators at finite
temperature are computed at future infinity. The quasinormal modes are obtained
in explicit form. Finally, we obtain an expression for the expectation value of
the number of particles produced at future infinity starting from a vacuum
state with no incoming particles at past infinity. Some of our results are used
to provide further evidence for a recent holographic proposal between the
rotating Nariai geometry and a two-dimensional conformal field theory.Comment: 35 + 1 pages, 9 figures; v3: typos correcte
Mass and Angular Momentum in General Relativity
We present an introduction to mass and angular momentum in General
Relativity. After briefly reviewing energy-momentum for matter fields, first in
the flat Minkowski case (Special Relativity) and then in curved spacetimes with
or without symmetries, we focus on the discussion of energy-momentum for the
gravitational field. We illustrate the difficulties rooted in the Equivalence
Principle for defining a local energy-momentum density for the gravitational
field. This leads to the understanding of gravitational energy-momentum and
angular momentum as non-local observables that make sense, at best, for
extended domains of spacetime. After introducing Komar quantities associated
with spacetime symmetries, it is shown how total energy-momentum can be
unambiguously defined for isolated systems, providing fundamental tests for the
internal consistency of General Relativity as well as setting the conceptual
basis for the understanding of energy loss by gravitational radiation. Finally,
several attempts to formulate quasi-local notions of mass and angular momentum
associated with extended but finite spacetime domains are presented, together
with some illustrations of the relations between total and quasi-local
quantities in the particular context of black hole spacetimes. This article is
not intended to be a rigorous and exhaustive review of the subject, but rather
an invitation to the topic for non-experts. In this sense we follow essentially
the expositions in Szabados 2004, Gourgoulhon 2007, Poisson 2004 and Wald 84,
and refer the reader interested in further developments to the existing
literature, in particular to the excellent and comprehensive review by Szabados
(2004).Comment: 41 pages. Notes based on the lecture given at the C.N.R.S. "School on
Mass" (June 2008) in Orleans, France. To appear as proceedings in the book
"Mass and Motion in General Relativity", eds. L. Blanchet, A. Spallicci and
B. Whiting. Some comments and references added
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