56 research outputs found
Low significance of evidence for black hole echoes in gravitational wave data
Recent detections of merging black holes allow observational tests of the
nature of these objects. In some proposed models, non-trivial structure at or
near the black hole horizon could lead to echo signals in gravitational wave
data. Recently, Abedi et al. claimed tentative evidence for repeating damped
echo signals following the gravitational-wave signals of the binary black hole
merger events recorded in the first observational period of the Advanced LIGO
interferometers. We reanalyse the same data, addressing some of the
shortcomings of their method using more background data and a modified
procedure. We find a reduced statistical significance for the claims of
evidence for echoes, calculating increased p-values for the null hypothesis of
echo-free noise. The reduced significance is entirely consistent with noise,
and so we conclude that the analysis of Abedi et al. does not provide any
observational evidence for the existence of Planck-scale structure at black
hole horizons.Comment: As accepted by Physical Review
Blip glitches in Advanced LIGO data
Blip glitches are short noise transients present in data from ground-based
gravitational-wave observatories. These glitches resemble the
gravitational-wave signature of massive binary black hole mergers. Hence, the
sensitivity of transient gravitational-wave searches to such high-mass systems
and other potential short duration sources is degraded by the presence of blip
glitches. The origin and rate of occurrence of this type of glitch have been
largely unknown. In this paper we explore the population of blip glitches in
Advanced LIGO during its first and second observing runs. On average, we find
that Advanced LIGO data contains approximately two blip glitches per hour of
data. We identify four subsets of blip glitches correlated with detector
auxiliary or environmental sensor channels, however the physical causes of the
majority of blips remain unclear
Legal Rights and Issues Surrounding Conception, Pregnancy, and Birth
Advances in medicine are reported almost daily in the media. Medical researchers have developed and are continuing to develop new methods of creating, saving, and prolonging life. This Special Project examines the impact that rapidly advancing medical technology has on the law governing conception, pregnancy, and birth.
Although medical techniques have advanced rapidly during the past decades, state and federal legislatures have responded in-adequately to the legal consequences of these new birth technologies. The resulting lag between technology and the law has forced courts to confront new situations that do not fit neatly into the statutory framework created to deal with past fact situations. For example, courts have applied statutes prohibiting child bartering to surrogate parenting cases and statutes prohibiting fetal experimentation to artificial insemination cases although it is clear that the legislators never considered such fact patterns when passing the statutes. A lag is inevitable because the law can only respond to, rather than predict, emerging medical developments. Nonetheless, legislators must respond promptly by confronting the new legal issues that result from new medical technologies.
One impediment to prompt legislative response to the lag between medical technology and the law is the controversial nature of the legal problems posed. Abortion continues to be an extremely controversial issue thirteen years after the Supreme Court legalized it in the landmark decision Roe v. Wade. The Baby Doe issue of whether to force hospitals and parents of severely deformed newborns to provide medical care is another extremely controversial issue. Baby Doe has become highly politicized as the Reagan administration, Congress, right-to-life groups, disability groups, medical professionals, and other groups have taken stances. Surrogate parenting also has produced controversial situations. In one incident, a New York couple contracted with a California surrogate mother. When the surrogate mother breached the agreement, the couple brought suit. The court discovered that the couple consisted of a man and a transsexual, thus raising the issue of whether transsexuals or homosexuals should be allowed to adopt children by contracting with surrogate mothers
The PyCBC search for gravitational waves from compact binary coalescence
We describe the PyCBC search for gravitational waves from compact-object
binary coalescences in advanced gravitational-wave detector data. The search
was used in the first Advanced LIGO observing run and unambiguously identified
two black hole binary mergers, GW150914 and GW151226. At its core, the PyCBC
search performs a matched-filter search for binary merger signals using a bank
of gravitational-wave template waveforms. We provide a complete description of
the search pipeline including the steps used to mitigate the effects of noise
transients in the data, identify candidate events and measure their statistical
significance. The analysis is able to measure false-alarm rates as low as one
per million years, required for confident detection of signals. Using data from
initial LIGO's sixth science run, we show that the new analysis reduces the
background noise in the search, giving a 30% increase in sensitive volume for
binary neutron star systems over previous searches.Comment: 29 pages, 7 figures, accepted by Classical and Quantum Gravit
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Changes in Local School Policies and Practices in Washington State After an Unfunded Physical Activity and Nutrition Mandate
Introduction: Policies and practices in schools may create environments that encourage and reinforce healthy behaviors and are thus a means for stemming the rising rates of childhood obesity. We assessed the effect of a 2005 statewide school physical activity and nutrition mandate on policies and practices in middle and high schools in Washington State.
Methods: We used 2002, 2004, and 2006 statewide School Health Profiles survey data from Washington, with Oregon as a comparison group, to create longitudinal linear regression models to describe changes in relevant school policies after the Washington statewide mandate. Policy area composite measures were generated by principal component factor analysis from survey questions about multiple binary measure policy and practice.
Results: Relative to expected trends without the mandate, we found significant percentage-point increases in various policies, including restricted access to competitive foods in middle and high schools (increased by 18.8-20.0 percentage points); school food practices (increased by 10.4 percentage points in middle schools); and eliminating exemptions from physical education (PE) for sports (16.6 percentage-point increase for middle schools), exemptions from PE for community activities (12.8 and 14.4 percentage-point increases for middle and high schools, respectively) and exemptions from PE for academics (18.1 percentage-point increase for middle schools).
Conclusion: Our results suggest that a statewide mandate had a modest effect on increasing physical activity and nutrition policies and practices in schools. Government policy is potentially an effective tool for addressing the childhood obesity epidemic through improvements in school physical activity and nutrition environments.This is the publisherâs final pdf. The published article is copyrighted by the Centers for Disease Control and Prevention, United States Government and can be found at: http://www.cdc.gov/pcd/current_issue.ht
Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severity
The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the presence of variants in each gene. An ensemble of LASSO logistic regression models was used to identify the most informative Boolean features with respect to the genetic bases of severity. The Boolean features selected by these logistic models were combined into an Integrated PolyGenic Score that offers a synthetic and interpretable index for describing the contribution of host genetics in COVID-19 severity, as demonstrated through testing in several independent cohorts. Selected features belong to ultra-rare, rare, low-frequency, and common variants, including those in linkage disequilibrium with known GWAS loci. Noteworthily, around one quarter of the selected genes are sex-specific. Pathway analysis of the selected genes associated with COVID-19 severity reflected the multi-organ nature of the disease. The proposed model might provide useful information for developing diagnostics and therapeutics, while also being able to guide bedside disease management. © 2021, The Author(s)
COVID-19 Severity and Cardiovascular Outcomes in SARS-CoV-2-Infected Patients With Cancer and Cardiovascular Disease
BACKGROUND: Data regarding outcomes among patients with cancer and co-morbid cardiovascular disease (CVD)/cardiovascular risk factors (CVRF) after SARS-CoV-2 infection are limited.
OBJECTIVES: To compare Coronavirus disease 2019 (COVID-19) related complications among cancer patients with and without co-morbid CVD/CVRF.
METHODS: Retrospective cohort study of patients with cancer and laboratory-confirmed SARS-CoV-2, reported to the COVID-19 and Cancer Consortium (CCC19) registry from 03/17/2020 to 12/31/2021. CVD/CVRF was defined as established CVD
RESULTS: Among 10,876 SARS-CoV-2 infected patients with cancer (median age 65 [IQR 54-74] years, 53% female, 52% White), 6253 patients (57%) had co-morbid CVD/CVRF. Co-morbid CVD/CVRF was associated with higher COVID-19 severity (adjusted OR: 1.25 [95% CI 1.11-1.40]). Adverse CV events were significantly higher in patients with CVD/CVRF (all
CONCLUSIONS: Co-morbid CVD/CVRF is associated with higher COVID-19 severity among patients with cancer, particularly those not receiving active cancer therapy. While infrequent, COVID-19 related CV complications were higher in patients with comorbid CVD/CVRF. (COVID-19 and Cancer Consortium Registry [CCC19]; NCT04354701)
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 nonâcritically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (nâ=â257), ARB (nâ=â248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; nâ=â10), or no RAS inhibitor (control; nâ=â264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ supportâfree days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ supportâfree days among critically ill patients was 10 (â1 to 16) in the ACE inhibitor group (nâ=â231), 8 (â1 to 17) in the ARB group (nâ=â217), and 12 (0 to 17) in the control group (nâ=â231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ supportâfree days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
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