46 research outputs found

    Measurement and subtraction of Schumann resonances at gravitational-wave interferometers

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    Correlated magnetic noise from Schumann resonances threatens to contaminate the observation of a stochastic gravitational-wave background in interferometric detectors. In previous work, we reported on the first effort to eliminate global correlated noise from the Schumann resonances using Wiener filtering, demonstrating as much as a factor of two reduction in the coherence between magnetometers on different continents. In this work, we present results from dedicated magnetometer measurements at the Virgo and KAGRA sites, which are the first results for subtraction using data from gravitational-wave detector sites. We compare these measurements to a growing network of permanent magnetometer stations, including at the LIGO sites. We show the effect of mutual magnetometer attraction, arguing that magnetometers should be placed at least one meter from one another. In addition, for the first time, we show how dedicated measurements by magnetometers near to the interferometers can reduce coherence to a level consistent with uncorrelated noise, making a potential detection of a stochastic gravitational-wave background possible

    Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

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    Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

    Control of paratuberculosis: who, why and how. A review of 48 countries

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    Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis

    Search for intermediate mass black hole binaries in the first observing run of Advanced LIGO

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    During their first observational run, the two Advanced LIGO detectors attained an unprecedented sensitivity, resulting in the first direct detections of gravitational-wave signals produced by stellar-mass binary black hole systems. This paper reports on an all-sky search for gravitational waves (GWs) from merging intermediate mass black hole binaries (IMBHBs). The combined results from two independent search techniques were used in this study: the first employs a matched-filter algorithm that uses a bank of filters covering the GW signal parameter space, while the second is a generic search for GW transients (bursts). No GWs from IMBHBs were detected; therefore, we constrain the rate of several classes of IMBHB mergers. The most stringent limit is obtained for black holes of individual mass 100 M ⊙, with spins aligned with the binary orbital angular momentum. For such systems, the merger rate is constrained to be less than 0.93 Gpc−3yr−1 in comoving units at the 90% confidence level, an improvement of nearly 2 orders of magnitude over previous upper limits

    First low-frequency Einstein@Home all-sky search for continuous gravitational waves in Advanced LIGO data

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    We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100 Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7 [1/root Hz]. At the frequency of best strain sensitivity, near 100 Hz, we set 90% confidence upper limits of 1.8 x 10(-25). At the low end of our frequency range, 20 Hz, we achieve upper limits of 3.9 x 10(-24). At 55 Hz we can exclude sources with ellipticities greater than 10(-5) within 100 pc of Earth with fiducial value of the principal moment of inertia of 10(38) kg m(2)

    Computer evaluation of the on-and-off design performance of an axial air turbine

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    An existing code for calculating axial turbine performance using multiple stream surfaces was modified and made to run on the equivalent of an HP- 1000 computer system. Calculations were made for the geometry of a 485 horsepower dual-discharge air-drive turbine for both on and off -design conditions. The results were compared with available data obtained at off -design speeds. Agreement of the flow rate and horsepower to within 51 was obtained.http://archive.org/details/computerevaluati00ciroLieutenant, United States NavyApproved for public release; distribution is unlimited

    Recent release from prison — A novel risk factor for intimate partner homicide

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    The United States has the highest per-capita incarceration rate and the largest prison population in the world. More than two thirds of recently incarcerated individuals will be arrested again within 3 years of release and may commit crimes as serious as homicide soon after discharge. The pattern of homicidal violence currently remains unknown for recently incarcerated homicide suspects (RIHS) and their victims. A retrospective analysis of the 36 states included in the 2003 to 2017 National Violent Death Reporting System was performed with a focus on RIHS and their victims. Pearson χ2 and Wilcoxon rank sum tests were used for comparison. There were 249 RIHS in the database of the 14,561 homicides where suspect recent incarceration status was documented. Compared with not-recently incarcerated suspects, RIHS were more likely to be White (41% vs. 29%, p < 0.001) and male (97% vs. 91%, p < 0.001). Recently incarcerated homicide suspects more often had a known relationship with the victim (75% vs. 51%, p < 0.001), and these homicides more often occurred in the victim's own home (43% vs. 34%, p = 0.006). Intimate partner violence was a factor in 31% of the RIHS cases (vs. 17%, p < 0.001). The homicide weapon was most likely to be a firearm (57.8%, p < 0.001). Only 6.4% of homicides were due to mental health illness. Gang violence, while more common in the RIHS group, was still only a precipitating factor in 12.0% of the homicides (vs. 7.4%, p = 0.006). Recently incarcerated homicide suspects are more likely to kill a known person in their own home with a firearm, and these homicides are frequently categorized as intimate partner homicides. Gang violence and mental health are not frequent precipitating factors in these deaths. Additional future interventions are urgently needed to eliminate these preventable deaths by alerting previous or current intimate partners of those being discharged from the prison system

    A pilot randomized controlled trial of 7 versus 14 days of antibiotic treatment for bloodstream infection on non-intensive care versus intensive care wards

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    Abstract Background The optimal treatment duration for patients with bloodstream infection is understudied. The Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness (BALANCE) pilot randomized clinical trial (RCT) determined that it was feasible to enroll and randomize intensive care unit (ICU) patients with bloodstream infection to 7 versus 14 days of treatment, and served as the vanguard for the ongoing BALANCE main RCT. We performed this BALANCE-Ward pilot RCT to examine the feasibility and impact of potentially extending the BALANCE main RCT to include patients hospitalized on non-ICU wards. Methods We conducted an open pilot RCT among a subset of six sites participating in the ongoing BALANCE RCT, randomizing patients with positive non-Staphylococcus aureus blood cultures on non-ICU wards to 7 versus 14 days of antibiotic treatment. The co-primary feasibility outcomes were recruitment rate and adherence to treatment duration protocol. We compared feasibility outcomes, patient/pathogen characteristics, and overall outcomes among those enrolled in this BALANCE-Ward and prior BALANCE-ICU pilot RCTs. We estimated the sample size and non-inferiority margin impacts of expanding the BALANCE main RCT to include non-ICU patients. Results A total of 134 patients were recruited over 47 site-months (mean 2.9 patients/site-month, median 1.0, range 0.1–4.4 patients/site-month). The overall recruitment rate exceeded the BALANCE-ICU pilot RCT (mean 1.10 patients/site-month, p < 0.0001). Overall protocol adherence also exceeded the adherence in the BALANCE-ICU pilot RCT (125/134, 93% vs 89/115, 77%, p = 0.0003). BALANCE-Ward patients were older, with lower Sequential Organ Failure Assessment scores, and higher proportions of infections caused by Escherichia coli and genito-urinary sources of bloodstream infection. The BALANCE-Ward pilot RCT patients had an overall 90-day mortality rate of 17/133 (12.8%), which was comparable to the 90-day mortality rate in the ICU pilot RCT (17/115, 14.8%) (p = 0.65). Simulation models indicated there would be minimal sample size and non-inferiority margin implications of expanding enrolment to increasing proportions of non-ICU versus ICU patients. Conclusion It is feasible to enroll non-ICU patients in a trial of 7 versus 14 days of antibiotics for bloodstream infection, and expanding the BALANCE RCT hospital-wide has the potential to improve the timeliness and generalizability of trial results. Trial registration Clinicaltrials.gov, NCT02917551. Registered on September 28, 2016
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