539 research outputs found
Process redesign of a surgical pathway improves access to cataract surgery for Aboriginal and Torres Strait Islander people in South East Queensland
The Institute for Urban Indigenous Health (IUIH) aimed to improve access to cataract surgery in urban South East Queensland (SEQ) for Indigenous Australians, without compromising clinical visual outcomes. The Penchansky and Levesque concept of access as the ‘fit’ between the patient’s needs and the ability of the system to meet those needs was used to inform the redesign of the mainstream cataract surgical pathway. The IUIH staff and community stakeholders mapped the traditional external cataract surgical pathway and then innovatively redesigned it to reduce the number of patients being removed by the system at key transition points. The integration of eye health within the primary health care (PHC) clinic has improved the continuity and coordination of care along the surgical pathway, and ensured the sustainability of collaborative partnerships with key external organisations. Audit data demonstrated a significant increase in utilisation of cataract surgical services after the process redesign. Previous studies have found that PHC models involving integration, coordination and continuity of care enhance patient health outcomes; however, the IUIH surgical model extends this to tertiary care. There is scope to apply this model to other surgical pathways and communities who experience access inequity
The effects of charge transfer inefficiency (CTI) on galaxy shape measurements
(Abridged) We examine the effects of charge transfer inefficiency (CTI)
during CCD readout on galaxy shape measurements required by studies of weak
gravitational lensing. We simulate a CCD readout with CTI such as that caused
by charged particle radiation damage. We verify our simulations on data from
laboratory-irradiated CCDs. Only charge traps with time constants of the same
order as the time between row transfers during readout affect galaxy shape
measurements. We characterize the effects of CTI on various galaxy populations.
We baseline our study around p-channel CCDs that have been shown to have charge
transfer efficiency up to an order of magnitude better than several models of
n-channel CCDs designed for space applications. We predict that for galaxies
furthest from the readout registers, bias in the measurement of galaxy shapes,
Delta(e), will increase at a rate of 2.65 +/- 0.02 x 10^(-4) per year at L2 for
accumulated radiation exposure averaged over the solar cycle. If uncorrected,
this will consume the entire shape measurement error budget of a dark energy
mission within about 4 years. Software mitigation techniques demonstrated
elsewhere can reduce this by a factor of ~10, bringing the effect well below
mission requirements. CCDs with higher CTI than the ones we studeied may not
meet the requirements of future dark energy missions. We discuss ways in which
hardware could be designed to further minimize the impact of CTI.Comment: 11 pages, 6 figures, and 2 tables. Accepted for publication in PAS
Radiation Tolerance of Fully-Depleted P-Channel CCDs Designed for the SNAP Satellite
Thick, fully depleted p-channel charge-coupled devices (CCDs) have been
developed at the Lawrence Berkeley National Laboratory (LBNL). These CCDs have
several advantages over conventional thin, n-channel CCDs, including enhanced
quantum efficiency and reduced fringing at near-infrared wavelengths and
improved radiation tolerance. Here we report results from the irradiation of
CCDs with 12.5 and 55 MeV protons at the LBNL 88-Inch Cyclotron and with 0.1-1
MeV electrons at the LBNL Co60 source. These studies indicate that the LBNL
CCDs perform well after irradiation, even in the parameters in which
significant degradation is observed in other CCDs: charge transfer efficiency,
dark current, and isolated hot pixels. Modeling the radiation exposure over a
six-year mission lifetime with no annealing, we expect an increase in dark
current of 20 e/pixel/hr, and a degradation of charge transfer efficiency in
the parallel direction of 3e-6 and 1e-6 in the serial direction. The dark
current is observed to improve with an annealing cycle, while the parallel CTE
is relatively unaffected and the serial CTE is somewhat degraded. As expected,
the radiation tolerance of the p-channel LBNL CCDs is significantly improved
over the conventional n-channel CCDs that are currently employed in space-based
telescopes such as the Hubble Space Telescope.Comment: 11 pages, 10 figures, submitted to IEEE Transaction
The DESI Experiment, a whitepaper for Snowmass 2013
The Dark Energy Spectroscopic Instrument (DESI) is a massively multiplexed
fiber-fed spectrograph that will make the next major advance in dark energy in
the timeframe 2018-2022. On the Mayall telescope, DESI will obtain spectra and
redshifts for at least 18 million emission-line galaxies, 4 million luminous
red galaxies and 3 million quasi-stellar objects, in order to: probe the
effects of dark energy on the expansion history using baryon acoustic
oscillations (BAO), measure the gravitational growth history through
redshift-space distortions, measure the sum of neutrino masses, and investigate
the signatures of primordial inflation. The resulting 3-D galaxy maps at z<2
and Lyman-alpha forest at z>2 will make 1%-level measurements of the distance
scale in 35 redshift bins, thus providing unprecedented constraints on
cosmological models.Comment: 14 pages, 4 figures, a White Paper for Snowmass 201
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Deciphering the complex interplay between microbiota, HPV, inflammation and cancer through cervicovaginal metabolic profiling
Background: Dysbiotic vaginal microbiota have been implicated as contributors to persistent HPV-mediated cervical carcinogenesis and genital inflammation with mechanisms unknown. Given that cancer is a metabolic disease, metabolic profiling of the cervicovaginal microenvironment has the potential to reveal the functional interplay between the host and microbes in HPV persistence and progression to cancer. Methods: Our study design included HPV-negative/positive controls, women with low-grade and high-grade cervical dysplasia, or cervical cancer (n = 78). Metabolic fingerprints were profiled using liquid chromatography-mass spectrometry. Vaginal microbiota and genital inflammation were analysed using 16S rRNA gene sequencing and immunoassays, respectively. We used an integrative bioinformatic pipeline to reveal host and microbe contributions to the metabolome and to comprehensively assess the link between HPV, microbiota, inflammation and cervical disease. Findings: Metabolic analysis yielded 475 metabolites with known identities. Unique metabolic fingerprints discriminated patient groups from healthy controls. Three-hydroxybutyrate, eicosenoate, and oleate/vaccenate discriminated (with excellent capacity) between cancer patients versus the healthy participants. Sphingolipids, plasmalogens, and linoleate positively correlated with genital inflammation. Non-Lactobacillus dominant communities, particularly in high-grade dysplasia, perturbed amino acid and nucleotide metabolisms. Adenosine and cytosine correlated positively with Lactobacillus abundance and negatively with genital inflammation. Glycochenodeoxycholate and carnitine metabolisms connected non-Lactobacillus dominance to genital inflammation. Interpretation: Cervicovaginal metabolic profiles were driven by cancer followed by genital inflammation, HPV infection, and vaginal microbiota. This study provides evidence for metabolite-driven complex host-microbe interactions as hallmarks of cervical cancer with future translational potential. (C) 2019 The Authors. Published by Elsevier B.V.Flinn Foundation [1974]; Banner Foundation in Obstetrics and Gynecology Research; National Institutes of Health NCI [P30 CA023074]Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Constraint on neutrino masses from SDSS-III/BOSS Ly-alpha forest and other cosmological probes
International audienceWe present constraints on the parameters of the CDM cosmologicalmodel in the presence of massive neutrinos, using the one-dimensionalLy forest power spectrum obtained with the Baryon OscillationSpectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS) byPalanque-Delabrouille et al. (2013), complemented by additional cosmologicalprobes. The interpretation of the measured Ly spectrum is done using asecond-order Taylor expansion of the simulated power spectrum. BOSS Ly data alone provide better bounds than previous Ly results,but are still poorly constraining, especially for the sum of neutrino masses, for which we obtain an upper bound of 1.1~eV (95\% CL), includingsystematics for both data and simulations. Ly constraints onCDM parameters and neutrino masses are compatible with CMB bounds fromthe Planck collaboration. Interestingly, the combination of Ly with CMBdata reduces the uncertainties significantly, due to very different directionsof degeneracy in parameter space, leading to the strongest cosmological boundto date on the total neutrino mass, ~eV at 95\% CL (with abest-fit in zero). Adding recent BAO results further tightens this constraintto ~eV at 95\% CL. This bound is nearly independent of thestatistical approach used, and of the different combinations of CMB and BAOdata sets considered in this paper in addition to Ly. Given themeasured values of the two squared mass differences , this resulttends to favor the normal hierarchy scenario against the inverted hierarchyscenario for the masses of the active neutrino species
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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