219 research outputs found
The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
We create a sample of spectroscopically identified galaxies with
from the Sloan Digital Sky Survey (SDSS) Data Release 7, covering 6813 deg.
Galaxies are chosen to sample the highest mass haloes, with an effective bias
of 1.5, allowing us to construct 1000 mock galaxy catalogs (described in Paper
II), which we use to estimate statistical errors and test our methods. We use
an estimate of the gravitational potential to "reconstruct" the linear density
fluctuations, enhancing the Baryon Acoustic Oscillation (BAO) signal in the
measured correlation function and power spectrum. Fitting to these
measurements, we determine Mpc; this is a better than 4 per cent distance measurement. This "fills
the gap" in BAO distance ladder between previously measured local and higher
redshift measurements, and affords significant improvement in constraining the
properties of dark energy. Combining our measurement with other BAO
measurements from BOSS and 6dFGS galaxy samples provides a 15 per cent
improvement in the determination of the equation of state of dark energy and
the value of the Hubble parameter at (). Our measurement is fully
consistent with the Planck results and the CDM concordance cosmology,
but increases the tension between PlanckBAO determinations and direct
measurements.Comment: Accepted by MNRAS, distance likelihood is available in source file
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: mock galaxy catalogues for the low-redshift sample
We present one thousand mock galaxy catalogues for the analysis of the Low
Redshift Sample (LOWZ, effective redshift z ~ 10.32) of the Baryon Oscillation
Spectroscopic Survey Data Releases 10 and 11. These mocks have been created
following the PTHalos method of Manera13 et al. (2013) revised to include new
developments. The main improvement is the introduction of a redshift dependence
in the Halo Occupation Distribution in order to account for the change of the
galaxy number density with redshift. These mock catalogues are used in the
analyses of the LOWZ galaxy clustering by the BOSS collaboration.Comment: 10 pages, 8 figure
The clustering of Galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey : including covariance matrix errors
JP acknowledges support from the UK Science & Technology Facilities Council (STFC) through the consolidated grant ST/K0090X/1 and from the European Research Council through the ‘Starting Independent Research’ grant 202686, MDEPUGS. AGS acknowledges support from the Trans-regional Collaborative Research Centre TR33 ‘The Dark Universe’ of the German Research Foundation (DFG).We present improved methodology for including covariance matrices in the error budget of Baryon Oscillation Spectroscopic Survey (BOSS) galaxy clustering measurements, revisiting Data Release 9 (DR9) analyses, and describing a method that is used in DR10/11 analyses presented in companion papers. The precise analysis method adopted is becoming increasingly important, due to the precision that BOSS can now reach: even using as many as 600 mock catalogues to estimate covariance of two-point clustering measurements can still lead to an increase in the errors of ∼20 per cent, depending on how the cosmological parameters of interest are measured. In this paper, we extend previous work on this contribution to the error budget, deriving formulae for errors measured by integrating over the likelihood, and to the distribution of recovered best-fitting parameters fitting the simulations also used to estimate the covariance matrix. Both are situations that previous analyses of BOSS have considered. We apply the formulae derived to baryon acoustic oscillation (BAO) and redshift-space distortion (RSD) measurements from BOSS in our companion papers. To further aid these analyses, we consider the optimum number of bins to use for two-point measurements using the monopole power spectrum or correlation function for BAO, and the monopole and quadrupole moments of the correlation function for anisotropic-BAO and RSD measurements.Publisher PDFPeer reviewe
Inpatient opioid prescribing patterns and their effect on rehospitalisations: a nested case-control study using data from a Swiss public acute hospital.
AIMS OF THE STUDY
Opioid prescriptions have increased in Switzerland, even though current guidelines warn of their harms. If opioids for postoperative analgesia are not tapered before hospital discharge, patients are at risk of adverse events such as constipation, drowsiness, dependence, tolerance and withdrawal. The aim of this study was to investigate and quantify the potential association between opioids prescribed at discharge from hospital and rehospitalisation.
METHODS
We conducted a nested case-control study using routinely collected electronic health records from a Swiss public acute hospital. Cases were patients aged 65 years or older admitted between November 2014 and December 2018, with documented opioid administration on the day of discharge and rehospitalisation within 18 or 30 days after discharge. Each case was matched to five controls for age, sex, year of hospitalisation and Charlson Comorbidity Index. We calculated odds ratios for 18-day and 30-day rehospitalisation based on exposure to opioids using a conditional logistic regression adjusted for potential confounders. Secondary analyses included stratifications into morphine-equivalent doses of <50 mg, 50-89 mg and ≥90 mg, and co-prescriptions of gabapentinoids and benzodiazepines.
RESULTS
Of 22,471 included patients, 3144 rehospitalisations were identified, of which 1698 were 18-day rehospitalisations and 1446 were 30-day rehospitalisations. Documented opioid administration on the day of discharge was associated with 30-day rehospitalisation after adjustment for confounders (adjusted odds ratio 1.48; 95% CI 1.25-1.75, p 50 mg were rare.
CONCLUSIONS
Patients receiving opioids on the day of discharge were 48% more likely to be readmitted to hospital within 30 days. Clinicians should aim to discontinue opioids started in hospital before discharge if possible. Patients receiving an opioid prescription should be educated and monitored as part of opioid stewardship programmes
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey : baryon acoustic oscillations in the Data Releases 10 and 11 Galaxy samples
We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations (BAO) in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey, which is part of the Sloan Digital Sky Survey III. Our results come from the Data Release 11 (DR11) sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range 0.2 < z < 0.7. We also compare these results with those from the publicly released DR9 and DR10 samples. Assuming a concordance Λ cold dark matter (ΛCDM) cosmological model, the DR11 sample covers a volume of 13 Gpc3 and is the largest region of the Universe ever surveyed at this density. We measure the correlation function and power spectrum, including density-field reconstruction of the BAO feature. The acoustic features are detected at a significance of over 7σ in both the correlation function and power spectrum. Fitting for the position of the acoustic features measures the distance relative to the sound horizon at the drag epoch, rd, which has a value of rd,fid = 149.28 Mpc in our fiducial cosmology. We find DV = (1264 ± 25 Mpc)(rd/rd,fid) at z = 0.32 and DV = (2056 ± 20 Mpc)(rd/rd,fid) at z = 0.57. At 1.0 per cent, this latter measure is the most precise distance constraint ever obtained from a galaxy survey. Separating the clustering along and transverse to the line of sight yields measurements at z = 0.57 of DA = (1421 ± 20 Mpc)(rd/rd,fid) and H = (96.8 ± 3.4 km s−1 Mpc−1)(rd,fid/rd). Our measurements of the distance scale are in good agreement with previous BAO measurements and with the predictions from cosmic microwave background data for a spatially flat CDM model with a cosmological constant.Publisher PDFPeer reviewe
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The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 9 Spectroscopic Galaxy Sample
We present measurements of galaxy clustering from the Baryon Oscillation
Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III
(SDSS-III). These use the Data Release 9 (DR9) CMASS sample, which contains
264,283 massive galaxies covering 3275 square degrees with an effective
redshift z=0.57 and redshift range 0.43 < z < 0.7. Assuming a concordance
Lambda-CDM cosmological model, this sample covers an effective volume of 2.2
Gpc^3, and represents the largest sample of the Universe ever surveyed at this
density, n = 3 x 10^-4 h^-3 Mpc^3. We measure the angle-averaged galaxy
correlation function and power spectrum, including density-field reconstruction
of the baryon acoustic oscillation (BAO) feature. The acoustic features are
detected at a significance of 5\sigma in both the correlation function and
power spectrum. Combining with the SDSS-II Luminous Red Galaxy Sample, the
detection significance increases to 6.7\sigma. Fitting for the position of the
acoustic features measures the distance to z=0.57 relative to the sound horizon
DV /rs = 13.67 +/- 0.22 at z=0.57. Assuming a fiducial sound horizon of 153.19
Mpc, which matches cosmic microwave background constraints, this corresponds to
a distance DV(z=0.57) = 2094 +/- 34 Mpc. At 1.7 per cent, this is the most
precise distance constraint ever obtained from a galaxy survey. We place this
result alongside previous BAO measurements in a cosmological distance ladder
and find excellent agreement with the current supernova measurements. We use
these distance measurements to constrain various cosmological models, finding
continuing support for a flat Universe with a cosmological constant.Comment: 33 page
Profiles of an Ideal Society:The Utopian Visions of Ordinary People
Throughout history, people have expressed the desire for an ideal society—a utopia. These imagined societies have motivated action for social change. Recent research has demonstrated this motivational effect among ordinary people in English-speaking countries, but we know little about the specific content of ordinary people’s utopian visions in different cultures. Here we report that a majority of samples from four countries—Australia, China, the United Kingdom, and the United States—converge on a small number of utopian visions: a Modern Green utopia, a Primitivist utopia, a Futurist utopia, and a Religious utopia. Although the prevalence of these utopia profiles differed across countries, there was a cross-cultural convergence in utopian visions. These shared visions may provide common ground for conversations about how to achieve a better future across cultural borders.</p
Health sector spending and spending on HIV/AIDS, tuberculosis, and malaria, and development assistance for health : progress towards Sustainable Development Goal 3
Background Sustainable Development Goal (SDG) 3 aims to "ensure healthy lives and promote well-being for all at all ages". While a substantial effort has been made to quantify progress towards SDG3, less research has focused on tracking spending towards this goal. We used spending estimates to measure progress in financing the priority areas of SDG3, examine the association between outcomes and financing, and identify where resource gains are most needed to achieve the SDG3 indicators for which data are available. Methods We estimated domestic health spending, disaggregated by source (government, out-of-pocket, and prepaid private) from 1995 to 2017 for 195 countries and territories. For disease-specific health spending, we estimated spending for HIV/AIDS and tuberculosis for 135 low-income and middle-income countries, and malaria in 106 malaria-endemic countries, from 2000 to 2017. We also estimated development assistance for health (DAH) from 1990 to 2019, by source, disbursing development agency, recipient, and health focus area, including DAH for pandemic preparedness. Finally, we estimated future health spending for 195 countries and territories from 2018 until 2030. We report all spending estimates in inflation-adjusted 2019 US7.9 trillion (95% uncertainty interval 7.8-8.0) in 2017 and is expected to increase to 20.2 billion (17.0-25.0) and on tuberculosis it was 5.1 billion (4.9-5.4). Development assistance for health was 374 million of DAH was provided for pandemic preparedness, less than 1% of DAH. Although spending has increased across HIV/AIDS, tuberculosis, and malaria since 2015, spending has not increased in all countries, and outcomes in terms of prevalence, incidence, and per-capita spending have been mixed. The proportion of health spending from pooled sources is expected to increase from 81.6% (81.6-81.7) in 2015 to 83.1% (82.8-83.3) in 2030. Interpretation Health spending on SDG3 priority areas has increased, but not in all countries, and progress towards meeting the SDG3 targets has been mixed and has varied by country and by target. The evidence on the scale-up of spending and improvements in health outcomes suggest a nuanced relationship, such that increases in spending do not always results in improvements in outcomes. Although countries will probably need more resources to achieve SDG3, other constraints in the broader health system such as inefficient allocation of resources across interventions and populations, weak governance systems, human resource shortages, and drug shortages, will also need to be addressed. Copyright (C) 2020 The Author(s). Published by Elsevier Ltd.Peer reviewe
Unbiased clustering estimates with the DESI fibre assignment
The Emission Line Galaxy survey made by the Dark Energy Spectroscopic
Instrument (DESI) survey will be created from five passes of the instrument on
the sky. On each pass, the constrained mobility of the ends of the fibres in
the DESI focal plane means that the angular-distribution of targets that can be
observed is limited. Thus, the clustering of samples constructed using a
limited number of passes will be strongly affected by missing targets. In two
recent papers, we showed how the effect of missing galaxies can be corrected
when calculating the correlation function using a weighting scheme for pairs.
Using mock galaxy catalogues we now show that this method provides an unbiased
estimator of the true correlation function for the DESI survey after any number
of passes. We use multiple mocks to determine the expected errors given one to
four passes, compared to an idealised survey observing an equivalent number of
randomly selected targets. On BAO scales, we find that the error is a factor 2
worse after one pass, but that after three or more passes, the errors are very
similar. Thus we find that the fibre assignment strategy enforced by the design
of DESI will not affect the cosmological measurements to be made by the survey,
and can be removed as a potential risk for this experiment.Comment: 11 pages, 8 figure
COVID-19 vaccination and birth outcomes of 186,990 women vaccinated before pregnancy: an England-wide cohort study
Background: COVID-19 vaccination in pregnancy is recommended by the World Health Organisation as effective and
safe. However, there remains a lack of robust evidence to inform vaccination choices for women of childbearing
potential in relation to their future pregnancies. Here we investigated the association between starting a course of
COVID-19 vaccination before pregnancy and birth outcomes.
Methods: We analysed England-wide linked electronic health records for all pregnancies reaching at least 24 weeks
gestation between 25th May 2021 and 28th October 2022. We estimated incidence rates and hazard ratios for
birth and pregnancy outcomes by pre-pregnancy COVID-19 vaccination status.
Findings: Based on 186,990 women, compared to starting a pregnancy unvaccinated, receiving COVID-19 vaccination
within 12 months before pregnancy was associated with lower risks of very and extremely preterm birth and smallfor-gestational age in term babies for any vaccine type (adjusted hazard ratio and 95% confidence interval: 0.74 [0.63,
0.88] and 0.94 [0.88, 1.00], respectively), and lower stillbirth risk in those receiving an mRNA vaccine (0.72 [0.52,
1.00]). Incidence of venous thromboembolism during pregnancy was higher amongst women receiving a viralvector, but not an mRNA vaccine (1.54 [1.10, 2.16] and 1.02 [0.70, 1.50], respectively). Results were generally
consistent for different dose regimens and across sensitivity analyses.
Interpretation: We found evidence that pregnancies starting within 12 months from a first COVID-19 vaccination,
compared to those in unvaccinated women, experienced fewer adverse birth outcomes, overall or in selected
subgroups of the general population, accounting for potential confounders. An mRNA vaccine should be
preferred to a viral-vector vaccine, to minimise safety issues, but where the latter is the only choice, it is still to be
preferred to starting a pregnancy unvaccinated. The venous thromboembolism risk of the viral-vector vaccine was
substantially lower compared to that attributable to SARS-CoV-2 infection in pregnancy or to commonly used
medications such as hormone replacement therapy and oral contraceptives in the non-pregnant population.
Funding: UK National Institute for Health and Care Research (NIHR), UKRI Medical Research Council, UK Research
and Innovation, The Alan Turing Institute, Health Data Research UK, the Department of Health and Social Care
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