62 research outputs found
The causes of falls: views of older people with sight impairment
Background Sight impairment increases with age and, compared with the general older population, older people with sight impairment are more likely to fall. There is a growing body of evidence on the views and perceptions of older people about falls, but little is published on the views of older people with sight impairment. Objective To explore what older people with sight impairment believe to be the causes of falls. Design A qualitative design was used, incorporating focus groups and interviews in which participants discussed falls and falls prevention. Framework analysis was employed to identify themes arising from participants' discussions of the causes of falls. Setting and participants Fifty-four community dwelling men and women with sight impairment, aged 65 and over, were recruited from across Greater Manchester, UK. Results Five types of factors were identified that were believed to cause falls: (i) health issues and changes in balance caused by ageing; (ii) cognitive and behavioural factors; (iii) the impact of sight impairment on getting around the home; (iv) the impact of sight impairment on negotiating the environment away from home; and (v) unexplained falls. Discussion and conclusions Older people with sight impairment reported many researched risk factors previously identified by older people without sight impairment but also described many perceived risks unique to people with sight impairment. There are few interventions to prevent falls aimed at older people with sight impairment, and the results of this study allow further tailoring of such interventions based on views of older people with sight impairment
Probing dark energy using baryonic oscillations in the galaxy power spectrum as a cosmological ruler
We show that the baryonic oscillations expected in the galaxy power spectrum
may be used as a "standard cosmological ruler'' to facilitate accurate
measurement of the cosmological equation of state. Our approach involves a
straight-forward measurement of the oscillation "wavelength'' in Fourier space,
which is fixed by fundamental linear physics in the early Universe and hence is
highly model-independent. We quantify the ability of future large-scale galaxy
redshift surveys with mean redshifts z~1 and z~3 to delineate the baryonic
peaks in the power spectrum, and derive corresponding constraints on the
parameter w describing the equation of state of the dark energy. For example, a
survey of three times the Sloan volume at z ~ 1 can produce a measurement with
accuracy dw ~ 0.1. We suggest that this method of measuring the dark energy
powerfully complements other probes such as Type Ia supernovae, and suffers
from a different (and arguably less serious) set of systematic uncertainties.Comment: Submitted to Astrophysical Journal, 11 pages, 8 figure
A feasibility study to prevent falls in older people who are sight impaired: the VIP2UK randomised controlled trial.
BACKGROUND: Published evaluations of successful interventions to prevent falls in people with sight impairment (SI) are limited. The aim of this feasibility study is to optimise the design and investigation of home safety (HS) and home exercise (HE) programmes to prevent falls in older people with SI. METHODS: A community-based feasibility study in north-west England comprising a three-arm randomised controlled trial (RCT) allocated participants to (1) a control group receiving usual care and social visits, (2) an experimental group receiving the HS programme and (3) an experimental group receiving the HS + HE programme. Participants were community-dwelling, aged 65 years and older and sight impaired. Primary outcome data on falls were collected continuously over 6 months. Secondary outcomes on physical activity (self-report and instrumented) and adherence were collected at baseline and 3 and 6 months for HE and at 6 months for the HS programme. Costs for the HS and HS + HE groups were calculated from logs of time spent on home visits, telephone calls and travel. The research assistant and statistician were blinded to group allocation. RESULTS: Altogether, 49 people were recruited over a 9-month period (randomised: 16 to control, 16 to HS, 17 to HS + HE). The interventions were implemented over 6 months by an occupational therapist at a cost per person (pounds sterling, 2011) of £249 (HS) and £674 (HS + HE). Eighty-eight percent (43/49) completed the trial and 6-month follow-up. At 6-month follow-up, 100 % reported partially or completely adhering to HS recommendations but evidence for adherence to HE was equivocal. Although self-reported physical activity increased, instrumented monitoring showed a decrease in walking activity. There were no statistically significant differences in falls between the groups; however, the study was not powered to detect a difference. CONCLUSION: It is feasible and acceptable for an occupational therapist to deliver HS and HE falls prevention programmes to people with SI living independently in the community. Future studies could access Local Authority Registers of people with SI to improve recruitment rates. Further research is required to identify how to improve adherence to HE and to measure changes in physical activity before conducting a definitive RCT. TRIAL REGISTRATION: ISRCTN53433311 , registered on 8 May 2014
Advanced cancer patient preferences for receiving molecular profiling results
Objective: This study aimed to discern preferences for receiving somatic molecular profiling (MP) results in cancer patients who have given consent to undergo testing.
Methods: We conducted a mixed‐methods study to explore patients’ views on which MP results they would like to receive and why. Advanced cancer patients (n=1299) completed questionnaires after giving consent to participate in a parent genomics study and undergoing MP. A subset of patients (n=20) participated in qualitative interviews.
Results: Almost all (96%) participants were interested in receiving results which would direct cancer treatment (i.e. were actionable). A smaller majority wanted to access results which were not actionable (64%) or were variants of unknown significance (60%). Most (86%) were interested in finding out about germline findings, though not as a priority. Themes identified in interview data were: 1) Cancer is the focus; 2) Trust in clinicians; and 3) Respect for a right not to know.
Conclusions: The majority of advanced cancer patients undergoing MP prioritised results which would lead to treatment options. They trusted their oncologists to help them navigate the results return process. While there was interest in knowing about other results, this was a lesser priority. Nevertheless, given high levels of interest in receiving all results, ethical aspects of not providing uninformative results requires further research, including a consideration of patient rationales for desiring this information and what health professionals can and should do to support patients in the absence of meaningful information being available.
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A combined measurement of cosmic growth and expansion from clusters of galaxies, the CMB and galaxy clustering
Combining galaxy cluster data from the ROSAT All-Sky Survey and the Chandra
X-ray Observatory, cosmic microwave background data from the Wilkinson
Microwave Anisotropy Probe, and galaxy clustering data from the WiggleZ Dark
Energy Survey, the 6-degree Field Galaxy Survey and the Sloan Digital Sky
Survey III, we test for consistency the cosmic growth of structure predicted by
General Relativity (GR) and the cosmic expansion history predicted by the
cosmological constant plus cold dark matter paradigm (LCDM). The combination of
these three independent, well studied measurements of the evolution of the mean
energy density and its fluctuations is able to break strong degeneracies
between model parameters. We model the key properties of cosmic growth with the
normalization of the matter power spectrum, sigma_8, and the cosmic growth
index, gamma, and those of cosmic expansion with the mean matter density,
Omega_m, the Hubble constant, H_0, and a kinematical parameter equivalent to
that for the dark energy equation of state, w. For a spatially flat geometry,
w=-1, and allowing for systematic uncertainties, we obtain sigma_8=0.785+-0.019
and gamma=0.570+0.064-0.063 (at the 68.3 per cent confidence level). Allowing
both w and gamma to vary we find w=-0.950+0.069-0.070 and gamma=0.533+-0.080.
To further tighten the constraints on the expansion parameters, we also include
supernova, Cepheid variable and baryon acoustic oscillation data. For w=-1, we
have gamma=0.616+-0.061. For our most general model with a free w, we measure
Omega_m=0.278+0.012-0.011, H_0=70.0+-1.3 km s^-1 Mpc^-1 and
w=-0.987+0.054-0.053 for the expansion parameters, and sigma_8=0.789+-0.019 and
gamma=0.604+-0.078 for the growth parameters. These results are in excellent
agreement with GR+LCDM (gamma~0.55; w=-1) and represent the tightest and most
robust simultaneous constraint on cosmic growth and expansion to date.Comment: 14 pages, 5 figures, 1 table. Matches the accepted version for MNRAS.
New sections 3 and 6 added, containing 2 new figures. Table extended. The
results including BAO data have been slightly modified due to an updated BAO
analysis. Conclusions unchange
The WiggleZ Dark Energy Survey: measuring the cosmic expansion history using the Alcock-Paczynski test and distant supernovae
Astronomical observations suggest that today's Universe is dominated by a
dark energy of unknown physical origin. One of the most notable consequences in
many models is that dark energy should cause the expansion of the Universe to
accelerate: but the expansion rate as a function of time has proven very
difficult to measure directly. We present a new determination of the cosmic
expansion history by combining distant supernovae observations with a
geometrical analysis of large-scale galaxy clustering within the WiggleZ Dark
Energy Survey, using the Alcock-Paczynski test to measure the distortion of
standard spheres. Our result constitutes a robust and non-parametric
measurement of the Hubble expansion rate as a function of time, which we
measure with 10-15% precision in four bins within the redshift range 0.1 < z <
0.9. We demonstrate that the cosmic expansion is accelerating, in a manner
independent of the parameterization of the cosmological model (although
assuming cosmic homogeneity in our data analysis). Furthermore, we find that
this expansion history is consistent with a cosmological-constant dark energy.Comment: 13 pages, 7 figures, accepted for publication by MNRA
The WiggleZ Dark Energy Survey: Joint measurements of the expansion and growth history at z < 1
We perform a joint determination of the distance-redshift relation and cosmic
expansion rate at redshifts z = 0.44, 0.6 and 0.73 by combining measurements of
the baryon acoustic peak and Alcock-Paczynski distortion from galaxy clustering
in the WiggleZ Dark Energy Survey, using a large ensemble of mock catalogues to
calculate the covariance between the measurements. We find that D_A(z) = (1205
+/- 114, 1380 +/- 95, 1534 +/- 107) Mpc and H(z) = (82.6 +/- 7.8, 87.9 +/- 6.1,
97.3 +/- 7.0) km/s/Mpc at these three redshifts. Further combining our results
with other baryon acoustic oscillation and distant supernovae datasets, we use
a Monte Carlo Markov Chain technique to determine the evolution of the Hubble
parameter H(z) as a stepwise function in 9 redshift bins of width dz = 0.1,
also marginalizing over the spatial curvature. Our measurements of H(z), which
have precision better than 7% in most redshift bins, are consistent with the
expansion history predicted by a cosmological-constant dark-energy model, in
which the expansion rate accelerates at redshift z < 0.7.Comment: 11 pages, 11 figures, accepted for publication in MNRA
The 6dF Galaxy Survey: z \approx 0 measurement of the growth rate and sigma_8
We present a detailed analysis of redshift-space distortions in the two-point
correlation function of the 6dF Galaxy Survey (6dFGS). The K-band selected
sub-sample which we employ in this study contains 81971 galaxies distributed
over 17000deg^2 with an effective redshift z = 0.067. By modelling the 2D
galaxy correlation function, xi(r_p,pi), we measure the parameter combination
f(z)sigma_8(z) = 0.423 +/- 0.055. Alternatively, by assuming standard gravity
we can break the degeneracy between sigma_8 and the galaxy bias parameter, b.
Combining our data with the Hubble constant prior from Riess et al (2011), we
measure sigma_8 = 0.76 +/- 0.11 and Omega_m = 0.250 +/- 0.022, consistent with
constraints from other galaxy surveys and the Cosmic Microwave Background data
from WMAP7. Combining our measurement of fsigma_8 with WMAP7 allows us to test
the relationship between matter and gravity on cosmic scales by constraining
the growth index of density fluctuations, gamma. Using only 6dFGS and WMAP7
data we find gamma = 0.547 +/- 0.088, consistent with the prediction of General
Relativity. We note that because of the low effective redshift of 6dFGS our
measurement of the growth rate is independent of the fiducial cosmological
model (Alcock-Paczynski effect). We also show that our conclusions are not
sensitive to the model adopted for non-linear redshift-space distortions. Using
a Fisher matrix analysis we report predictions for constraints on fsigma_8 for
the WALLABY survey and the proposed TAIPAN survey. The WALLABY survey will be
able to measure fsigma_8 with a precision of 4-10%, depending on the modelling
of non-linear structure formation. This is comparable to the predicted
precision for the best redshift bins of the Baryon Oscillation Spectroscopic
Survey (BOSS), demonstrating that low-redshift surveys have a significant role
to play in future tests of dark energy and modified gravity.Comment: 17 pages, 13 figures, 1 tabl
Sketching women in court: The visual construction of co-accused women in court drawings
This paper explores the visual construction and representation of co-accused women offenders in court drawings. It utilises three case studies of female co-defendants who appeared in the England and Wales court system between 2003 and 2013. In doing so this paper falls into three parts. The first part considers the emergence of the sub-discipline, visual criminology and examines what is known about the visual representation of female offenders. The second part presents the findings of an empirical investigation, which involved engaging in a critical, reflexive visual analysis of a selection of court drawings of three female co-offenders. The third part discusses the ways in which the court artists' interpretation, the conventions of court sketching, and motifs of female offenders as secondary actors, drew on existing myths and prejudices by representing the women as listening, remorseless ‘others’
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