198 research outputs found
SARS-CoV-2 Mitigation Strategies, Testing, and Cases at 254 Jails in the US Southeast, October 2020 to May 2021
Objectives. To characterize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mitigation strategies, testing, and cases across county jails in the Southeastern United States, examining variability by jail characteristics. Methods. We administered a 1-time telephone survey to personnel of 254 jails in Alabama, Georgia, North Carolina, and South Carolina between October 2020 and May 2021. Results. Some SARS-CoV-2 mitigation strategies (e.g., screening at intake, isolation and masking for symptomatic persons) were commonly reported (≥ 75% of jails). Other measures, such as masking regardless of symptoms (52%) and screening at release (26%), were less common and varied by jail state or population size. Overall, 41% of jails reported no SARS-CoV-2 testing in the past 30 days. Jails with testing (59%) tested a median of 6 per 100 incarcerated persons; of those jails, one third reported 1 or more cases of positive tests. Although most jails detected no cases, in the 20% of all jails with 1 or more case in the past 30 days, 1 in 5 tests was positive. Conclusions. There was low testing coverage and variable implementation of SARS-CoV-2 mitigation strategies in Southeastern US jails during the first year of the COVID-19 pandemic
Medicaid Enrollment among Prison Inmates in a Non-expansion State: Exploring Predisposing, Enabling, and Need Factors Related to Enrollment Pre-incarceration and Post-Release
Prison inmates suffer from a heavy burden of physical and mental health problems and have considerable need for healthcare and coverage after prison release. The Affordable Care Act may have increased Medicaid access for some of those who need coverage in Medicaid expansion states, but inmates in non-expansion states still have high need for Medicaid coverage and face unique barriers to enrollment. We sought to explore barriers and facilitators to Medicaid enrollment among prison inmates in a non-expansion state. We conducted qualitative interviews with 20 recently hospitalized male prison inmates who had been approached by a prison social worker due to probable Medicaid eligibility, as determined by the inmates’ financial status, health, and past Medicaid enrollment. Interviews were transcribed verbatim and analyzed using a codebook with both thematic and interpretive codes. Coded interview text was then analyzed to identify predisposing, enabling, and need factors related to participants’ Medicaid enrollment prior to prison and intentions to enroll after release. Study participants’ median age, years incarcerated at the time of the interview, and projected remaining sentence length were 50, 4, and 2 years, respectively. Participants were categorized into three sub-groups based on their self-reported experience with Medicaid_ (1) those who never applied for Medicaid before prison (n = 6); (2) those who unsuccessfully attempted to enroll in Medicaid before prison (n = 3); and (3) those who enrolled in Medicaid before prison (n = 11). The six participants who had never applied to Medicaid before their incarceration did not hold strong attitudes about Medicaid and mostly had little need for Medicaid due to being generally healthy or having coverage available from other sources such as the Veteran’s Administration. However, one inmate who had never applied for Medicaid struggled considerably to access mental healthcare due to lapses in employer-based health coverage and attributed his incarceration to this unmet need for treatment. Three inmates with high medical need had their Medicaid applications rejected at least once pre-incarceration, resulting in periods without health coverage that led to worsening health and financial hardship for two of them. Eleven inmates with high medical need enrolled in Medicaid without difficulty prior to their incarceration, largely due to enabling factors in the form of assistance with the application by their local Department of Social Services or Social Security Administration, their mothers, medical providers, or prison personnel during a prior incarceration. Nearly all inmates acknowledged that they would need health coverage after release from prison, and more than half reported that they would need to enroll in Medicaid to gain healthcare coverage following their release. Although more population-based assessments are necessary, our findings suggest that greater assistance with Medicaid enrollment may be a key factor so that people in the criminal justice system who qualify for Medicaid—and other social safety net programs—may gain their rightful access to these benefits. Such access may benefit not only the individuals themselves but also the communities to which they return
Methamphetamine Use, Transmission Risk Behavior and Internet Use Among HIV-Infected Patients in Medical Care, San Francisco, 2008
Methamphetamine use is associated with adverse health outcomes and HIV incidence. Few studies have assessed methamphetamine use, sexual behavior and Internet use among HIV-infected patients. Surveys were administered to a sample of HIV-infected patients seeking medical care in a San Francisco county hospital and university-based clinic. In 2008, 35% of homosexual participants, 26% of heterosexual participants and 11% of female participants reported methamphetamine use in the past year. Of participants, 29% reported using the Internet to find sex partners; Internet-users versus non-Internet-users reported a higher median number of sex partners in 6 months (4 vs. 1), were more likely to report unprotected sex (32 vs. 10%), and higher rates of methamphetamine use in the past 12 months (48 vs. 24%). Given the association among methamphetamine use, increased sex partners and Internet use, the Internet may present a new and effective medium for interventions to reduce methamphetamine-associated sexual risk behavior
Changes in socioeconomic inequality in Indonesian children's cognitive function from 2000 to 2007: a decomposition analysis
Background: Measuring social inequalities in health is common; however, research examining inequalities in child cognitive function is more limited. We investigated household expenditure-related inequality in children’s cognitive function in Indonesia in 2000 and 2007, the contributors to inequality in both time periods, and changes in the contributors to cognitive function inequalities between the periods. Methods: Data from the 2000 and 2007 round of the Indonesian Family Life Survey (IFLS) were used. Study participants were children aged 7–14 years (n = 6179 and n = 6680 in 2000 and 2007, respectively). The relative concentration index (RCI) was used to measure the magnitude of inequality. Contribution of various contributors to inequality was estimated by decomposing the concentration index in 2000 and 2007. Oaxaca-type decomposition was used to estimate changes in contributors to inequality between 2000 and 2007. Results: Expenditure inequality decreased by 45% from an RCI = 0.29 (95% CI 0.22 to 0.36) in 2000 to 0.16 (95% CI 0.13 to 0.20) in 2007 but the burden of poorer cognitive function was higher among the disadvantaged in both years. The largest contributors to inequality in child cognitive function were inequalities in per capita expenditure, use of improved sanitation and maternal high school attendance. Changes in maternal high school participation (27%), use of improved sanitation (25%) and per capita expenditures (18%) were largely responsible for the decreasing inequality in children’s cognitive function between 2000 and 2007. Conclusions: Government policy to increase basic education coverage for women along with economic growth may have influenced gains in children’s cognitive function and reductions in inequalities in Indonesia.Amelia Maika, Murthy N. Mittinty, Sally Brinkman, Sam Harper, Elan Satriawan, John W. Lync
A Roadmap for Astrophysics and Cosmology with High-Redshift 21 cm Intensity Mapping
In this white paper, we lay out a US roadmap for high-redshift 21 cm
cosmology (30 < z < 6) in the 2020s. Beginning with the currently-funded HERA
and MWA Phase II projects and advancing through the decade with a coordinated
program of small-scale instrumentation, software, and analysis projects
targeting technology development, this roadmap incorporates our current best
understanding of the systematics confronting 21 cm cosmology into a plan for
overcoming them, enabling next-generation, mid-scale 21 cm arrays to be
proposed late in the decade. Submitted for consideration by the Astro2020
Decadal Survey Program Panel for Radio, Millimeter, and Submillimeter
Observations from the Ground as a Medium-Sized Project.Comment: 10 pages (plus a cover page and references), 6 figures. Submitted as
a APC White Paper for Astro202
What does an interferometer really measure? Including instrument and data characteristics in the reconstruction of the 21cm power spectrum
Combining the visibilities measured by an interferometer to form a
cosmological power spectrum is a complicated process in which the window
functions play a crucial role. In a delay-based analysis, the mapping between
instrumental space, made of per-baseline delay spectra, and cosmological space
is not a one-to-one relation. Instead, neighbouring modes contribute to the
power measured at one point, with their respective contributions encoded in the
window functions. To better understand the power spectrum measured by an
interferometer, we assess the impact of instrument characteristics and analysis
choices on the estimator by deriving its exact window functions, outside of the
delay approximation. Focusing on HERA as a case study, we find that
observations made with long baselines tend to correspond to enhanced low-k
tails of the window functions, which facilitate foreground leakage outside the
wedge, whilst the choice of bandwidth and frequency taper can help narrow them
down. With the help of simple test cases and more realistic visibility
simulations, we show that, apart from tracing mode mixing, the window functions
can accurately reconstruct the power spectrum estimator of simulated
visibilities. We note that the window functions depend strongly on the
chromaticity of the beam, and less on its spatial structure - a Gaussian
approximation, ignoring side lobes, is sufficient. Finally, we investigate the
potential of asymmetric window functions, down-weighting the contribution of
low-k power to avoid foreground leakage. The window functions presented in this
work correspond to the latest HERA upper limits for the full Phase I data. They
allow an accurate reconstruction of the power spectrum measured by the
instrument and can be used in future analyses to confront theoretical models
and data directly in cylindrical space.Comment: 18 pages, 18 figures, submitted to MNRAS. Comments welcome
Characterization Of Inpaint Residuals In Interferometric Measurements of the Epoch Of Reionization
Radio Frequency Interference (RFI) is one of the systematic challenges
preventing 21cm interferometric instruments from detecting the Epoch of
Reionization. To mitigate the effects of RFI on data analysis pipelines,
numerous inpaint techniques have been developed to restore RFI corrupted data.
We examine the qualitative and quantitative errors introduced into the
visibilities and power spectrum due to inpainting. We perform our analysis on
simulated data as well as real data from the Hydrogen Epoch of Reionization
Array (HERA) Phase 1 upper limits. We also introduce a convolutional neural
network that capable of inpainting RFI corrupted data in interferometric
instruments. We train our network on simulated data and show that our network
is capable at inpainting real data without requiring to be retrained. We find
that techniques that incorporate high wavenumbers in delay space in their
modeling are best suited for inpainting over narrowband RFI. We also show that
with our fiducial parameters Discrete Prolate Spheroidal Sequences (DPSS) and
CLEAN provide the best performance for intermittent ``narrowband'' RFI while
Gaussian Progress Regression (GPR) and Least Squares Spectral Analysis (LSSA)
provide the best performance for larger RFI gaps. However we caution that these
qualitative conclusions are sensitive to the chosen hyperparameters of each
inpainting technique. We find these results to be consistent in both simulated
and real visibilities. We show that all inpainting techniques reliably
reproduce foreground dominated modes in the power spectrum. Since the
inpainting techniques should not be capable of reproducing noise realizations,
we find that the largest errors occur in the noise dominated delay modes. We
show that in the future, as the noise level of the data comes down, CLEAN and
DPSS are most capable of reproducing the fine frequency structure in the
visibilities of HERA data.Comment: 26 pages, 18 figure
Direct Optimal Mapping Image Power Spectrum and its Window Functions
The key to detecting neutral hydrogen during the epoch of reionization (EoR)
is to separate the cosmological signal from the dominating foreground
radiation. We developed direct optimal mapping (Xu et al. 2022) to map
interferometric visibilities; it contains only linear operations, with full
knowledge of point spread functions from visibilities to images. Here we
present an FFT-based image power spectrum and its window functions based on
direct optimal mapping. We use noiseless simulation, based on the Hydrogen
Epoch of Reionization Array (HERA) Phase I configuration, to study the image
power spectrum properties. The window functions show power leakage
from the foreground-dominated region into the EoR window; the 2D and 1D power
spectra also verify the separation between the foregrounds and the EoR.
Furthermore, we simulated visibilities from a -complete array and
calculated its image power spectrum. The result shows that the foreground--EoR
leakage is further suppressed below , dominated by the tapering
function sidelobes; the 2D power spectrum does not show signs of the horizon
wedge. The -complete result provides a reference case for future 21cm
cosmology array designs.Comment: Submitted to Ap
Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array
Motivated by the desire for wide-field images with well-defined statistical
properties for 21cm cosmology, we implement an optimal mapping pipeline that
computes a maximum likelihood estimator for the sky using the interferometric
measurement equation. We demonstrate this direct optimal mapping with data from
the Hydrogen Epoch of Reionization (HERA) Phase I observations. After
validating the pipeline with simulated data, we develop a maximum likelihood
figure-of-merit for comparing four sky models at 166MHz with a bandwidth of
100kHz. The HERA data agree with the GLEAM catalogs to <10%. After subtracting
the GLEAM point sources, the HERA data discriminate between the different
continuum sky models, providing most support for the model of Byrne et al.
2021. We report the computation cost for mapping the HERA Phase I data and
project the computation for the HERA 320-antenna data; both are feasible with a
modern server. The algorithm is broadly applicable to other interferometers and
is valid for wide-field and non-coplanar arrays.Comment: 16 pages, 10 figures, 2 tables, published on Ap
Validation of the HERA Phase i Epoch of Reionization 21 cm Power Spectrum Software Pipeline
We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in the Phase I upper-limit analysis on wholly synthetic data satisfying the assumptions of that analysis, not addressing whether the actual data meet these assumptions. We discuss the organization of this validation approach, the specific modular tests performed, and the construction of the end-to-end simulations. We explicitly discuss the limitations in scope of the current simulation effort. With mock visibility data generated from a known analytic power spectrum and a wide range of realistic instrumental effects and foregrounds, we demonstrate that the current pipeline produces power spectrum estimates that are consistent with known analytic inputs to within thermal noise levels (at the 2σ level) for k > 0.2h Mpc-1 for both bands and fields considered. Our input spectrum is intentionally amplified to enable a strong "detection"at k ∼ 0.2 h Mpc-1 - at the level of ∼25σ - with foregrounds dominating on larger scales and thermal noise dominating at smaller scales. Our pipeline is able to detect this amplified input signal after suppressing foregrounds with a dynamic range (foreground to noise ratio) of ⪆107. Our validation test suite uncovered several sources of scale-independent signal loss throughout the pipeline, whose amplitude is well-characterized and accounted for in the final estimates. We conclude with a discussion of the steps required for the next round of data analysis
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