372 research outputs found

    Diet modifies the association between alcohol consumption and severe alcohol-related liver disease incidence

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    \ua9 The Author(s) 2024.It is elusive why some heavy drinkers progress to severe alcohol-related liver disease (ALD) while others do not. This study aimed to investigate if the association between alcohol consumption and severe ALD is modified by diet. This prospective study included 303,269 UK Biobank participants. Alcohol consumption and diet were self-reported. The diet score was created from 4 items selected using LASSO. Cox proportional hazard model showed that the diet score was monotonically associated with severe ALD risk, adjusted for sociodemographics, lifestyle factors, and alcohol consumption. Relative excess risk due to interaction analysis indicated that having a higher ALD diet score and a higher alcohol consumption simultaneously confers to 2.44 times (95% CI: 1.06-3.83) higher risk than the sum of excess risk of each factor. In this work, we show that people who have a poor diet might be more susceptible to severe ALD due to alcohol consumption

    Is older age associated with COVID-19 mortality in the absence of other risk factors? General population cohort study of 470,034 participants

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    Introduction: Older people have been reported to be at higher risk of COVID-19 mortality. This study explored the factors mediating this association and whether older age was associated with increased mortality risk in the absence of other risk factors. Methods: In UK Biobank, a population cohort study, baseline data were linked to COVID-19 deaths. Poisson regression was used to study the association between current age and COVID-19 mortality. Results: Among eligible participants, 438 (0.09%) died of COVID-19. Current age was associated exponentially with COVID-19 mortality. Overall, participants aged ≥75 years were at 13-fold (95% CI 9.13–17.85) mortality risk compared with those <65 years. Low forced expiratory volume in 1 second, high systolic blood pressure, low handgrip strength, and multiple long-term conditions were significant mediators, and collectively explained 39.3% of their excess risk. The associations between these risk factors and COVID-19 mortality were stronger among older participants. Participants aged ≥75 without additional risk factors were at 4-fold risk (95% CI 1.57–9.96, P = 0.004) compared with all participants aged <65 years. Conclusions: Higher COVID-19 mortality among older adults was partially explained by other risk factors. ‘Healthy’ older adults were at much lower risk. Nonetheless, older age was an independent risk factor for COVID-19 mortality

    All-sky search in early O3 LIGO data for continuous gravitational-wave signals from unknown neutron stars in binary systems

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    Rapidly spinning neutron stars are promising sources of continuous gravitational waves. Detecting such a signal would allow probing of the physical properties of matter under extreme conditions. A significant fraction of the known pulsar population belongs to binary systems. Searching for unknown neutron stars in binary systems requires specialized algorithms to address unknown orbital frequency modulations. We present a search for continuous gravitational waves emitted by neutron stars in binary systems in early data from the third observing run of the Advanced LIGO and Advanced Virgo detectors using the semicoherent, GPU-accelerated, binaryskyhough pipeline. The search analyzes the most sensitive frequency band of the LIGO detectors, 50-300 Hz. Binary orbital parameters are split into four regions, comprising orbital periods of three to 45 days and projected semimajor axes of two to 40 light seconds. No detections are reported. We estimate the sensitivity of the search using simulated continuous wave signals, achieving the most sensitive results to date across the analyzed parameter space

    GWTC-2: Compact Binary Coalescences Observed by LIGO and Virgo during the First Half of the Third Observing Run

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    International audienceWe report on gravitational wave discoveries from compact binary coalescences detected by Advanced LIGO and Advanced Virgo in the first half of the third observing run (O3a) between 1 April 2019 15:00 UTC and 1 October 2019 15:00. By imposing a false-alarm-rate threshold of two per year in each of the four search pipelines that constitute our search, we present 39 candidate gravitational wave events. At this threshold, we expect a contamination fraction of less than 10%. Of these, 26 candidate events were reported previously in near real-time through GCN Notices and Circulars; 13 are reported here for the first time. The catalog contains events whose sources are black hole binary mergers up to a redshift of ~0.8, as well as events whose components could not be unambiguously identified as black holes or neutron stars. For the latter group, we are unable to determine the nature based on estimates of the component masses and spins from gravitational wave data alone. The range of candidate events which are unambiguously identified as binary black holes (both objects 3 M\geq 3~M_\odot) is increased compared to GWTC-1, with total masses from 14 M\sim 14~M_\odot for GW190924_021846 to 150 M\sim 150~M_\odot for GW190521. For the first time, this catalog includes binary systems with significantly asymmetric mass ratios, which had not been observed in data taken before April 2019. We also find that 11 of the 39 events detected since April 2019 have positive effective inspiral spins under our default prior (at 90% credibility), while none exhibit negative effective inspiral spin. Given the increased sensitivity of Advanced LIGO and Advanced Virgo, the detection of 39 candidate events in ~26 weeks of data (~1.5 per week) is consistent with GWTC-1

    Search for lensing signatures in the gravitational-wave observations from the first half of LIGO-Virgo's third observing run

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    We search for signatures of gravitational lensing in the gravitational-wave signals from compact binary coalescences detected by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) and Advanced Virgo during O3a, the first half of their third observing run. We study: (1) the expected rate of lensing at current detector sensitivity and the implications of a non-observation of strong lensing or a stochastic gravitational-wave background on the merger-rate density at high redshift; (2) how the interpretation of individual high-mass events would change if they were found to be lensed; (3) the possibility of multiple images due to strong lensing by galaxies or galaxy clusters; and (4) possible wave-optics effects due to point-mass microlenses. Several pairs of signals in the multiple-image analysis show similar parameters and, in this sense, are nominally consistent with the strong lensing hypothesis. However, taking into account population priors, selection effects, and the prior odds against lensing, these events do not provide sufficient evidence for lensing. Overall, we find no compelling evidence for lensing in the observed gravitational-wave signals from any of these analyses

    Search for gravitational-wave transients associated with magnetar bursts in Advanced LIGO and Advanced Virgo data from the third observing run

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    Gravitational waves are expected to be produced from neutron staroscillations associated with magnetar giant flares and short bursts. We presentthe results of a search for short-duration (milliseconds to seconds) andlong-duration (\sim 100 s) transient gravitational waves from 13 magnetarshort bursts observed during Advanced LIGO, Advanced Virgo and KAGRA's thirdobservation run. These 13 bursts come from two magnetars, SGR 1935++2154 andSwift J1818.0-1607. We also include three other electromagnetic burst eventsdetected by Fermi GBM which were identified as likely coming from one or moremagnetars, but they have no association with a known magnetar. No magnetargiant flares were detected during the analysis period. We find no evidence ofgravitational waves associated with any of these 16 bursts. We place upperbounds on the root-sum-square of the integrated gravitational-wave strain thatreach 2.2×10232.2 \times 10^{-23} /Hz/\sqrt{\text{Hz}} at 100 Hz for theshort-duration search and 8.7×10238.7 \times 10^{-23} /Hz/\sqrt{\text{Hz}} at 450450 Hzfor the long-duration search, given a detection efficiency of 50%. For aringdown signal at 1590 Hz targeted by the short-duration search the limit isset to 1.8×10221.8 \times 10^{-22} /Hz/\sqrt{\text{Hz}}. Using the estimated distanceto each magnetar, we derive upper bounds on the emitted gravitational-waveenergy of 3.2×10433.2 \times 10^{43} erg (7.3×10437.3 \times 10^{43} erg) for SGR1935++2154 and 8.2×10428.2 \times 10^{42} erg (2.8×10432.8 \times 10^{43} erg) for SwiftJ1818.0-1607, for the short-duration (long-duration) search. Assumingisotropic emission of electromagnetic radiation of the burst fluences, weconstrain the ratio of gravitational-wave energy to electromagnetic energy forbursts from SGR 1935++2154 with available fluence information. The lowest ofthese ratios is 3×1033 \times 10^3.<br

    All-sky search for continuous gravitational waves from isolated neutron stars using Advanced LIGO and Advanced Virgo O3 data

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    We present results of an all-sky search for continuous gravitational waves which can be produced by spinning neutron stars with an asymmetry around their rotation axis, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. Four different analysis methods are used to search in a gravitational-wave frequency band from 10 to 2048 Hz and a first frequency derivative from 108-10^{-8} to 10910^{-9} Hz/s. No statistically-significant periodic gravitational-wave signal is observed by any of the four searches. As a result, upper limits on the gravitational-wave strain amplitude h0h_0 are calculated. The best upper limits are obtained in the frequency range of 100 to 200 Hz and they are 1.1×1025{\sim}1.1\times10^{-25} at 95\% confidence-level. The minimum upper limit of 1.10×10251.10\times10^{-25} is achieved at a frequency 111.5 Hz. We also place constraints on the rates and abundances of nearby planetary- and asteroid-mass primordial black holes that could give rise to continuous gravitational-wave signals.Comment: 23 main text pages, 17 figure

    All-sky search in early O3 LIGO data for continuous gravitational-wave signals from unknown neutron stars in binary systems

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    Rapidly spinning neutron stars are promising sources of persistent, continuous gravitational waves. Detecting such a signal would allow probing of the physical properties of matter under extreme conditions. A significant fraction of the known pulsar population belongs to binary systems. Searching for unknown neutron stars in binary systems requires specialized algorithms to address unknown orbital frequency modulations. We present a search for continuous gravitational waves emitted by neutron stars in binary systems in early data from the third observing run of the Advanced LIGO and Advanced Virgo detectors using the semicoherent, GPU-accelerated, BinarySkyHough pipeline. The search analyzes the most sensitive frequency band of the LIGO detectors, 50 - 300 Hz. Binary orbital parameters are split into four regions, comprising orbital periods of 3 - 45 days and projected semimajor axes of 2 - 40 light-seconds. No detections are reported. We estimate the sensitivity of the search using simulated continuous wave signals, achieving the most sensitive results to date across the analyzed parameter space

    GWTC-2.1: Deep Extended Catalog of Compact Binary Coalescences Observed by LIGO and Virgo During the First Half of the Third Observing Run

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    The second gravitational-wave transient catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Advanced Virgo detectors between 1 April 2019 15:00 UTC and 1 October 2019 15:00 UTC. Here, we present GWTC-2.1, which reports on a deeper list of candidate events observed over the same period. We analyze the final version of the strain data over this period, which is now publicly released. We employ three matched-filter search pipelines for candidate identification, and estimate the probability of astrophysical origin for each candidate event. While GWTC-2 used a false alarm rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass a false alarm rate threshold of 2 per day. We calculate the source properties of a subset of 44 high-significance candidates that have a probability of astrophysical origin greater than 0.5, using the default priors. Of these candidates, 36 have been reported in GWTC-2. If the 8 additional high-significance candidates presented here are astrophysical, the mass range of candidate events that are unambiguously identified as binary black holes (both objects 3M\geq 3M_\odot) is increased compared to GWTC-2, with total masses from 14M\sim 14M_\odot for GW190924_021846 to 184M\sim 184M_\odot for GW190426_190642. The primary components of two new candidate events (GW190403_051519 and GW190426_190642) fall in the mass gap predicted by pair-instability supernova theory. We also expand the population of binaries with significantly asymmetric mass ratios reported in GWTC-2 by an additional two events (q<0.61q \lt 0.61 and q<0.62q \lt 0.62 at 90%90\% credibility for GW190403_051519 and GW190917_114630 respectively), and find that 2 of the 8 new events have effective inspiral spins χeff>0\chi_\mathrm{eff} > 0 (at 90%90\% credibility), while no binary is consistent with χeff<0\chi_\mathrm{eff} \lt 0 at the same significance
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