1,011 research outputs found

    Testing General Relativity with LISA including Spin Precession and Higher Harmonics in the Waveform

    Full text link
    We compute the accuracy at which a LISA-like space-based gravitational wave detector will be able to observe deviations from General Relativity in the low frequency approximation. To do so, we introduce six correction parameters that account for modified gravity in the second post-Newtonian gravitational wave phase for inspiralling supermassive black hole binaries with spin precession on quasi-circular orbits. Our implementation can be regarded as a subset of the ppE formalism developed by Yunes and Pretorius, being able to investigate also next-to-leading order effects. In order to find error distributions for the alternative theory parameters, we use the Fisher information formalism and carry out Monte Carlo simulations for 17 different binary black hole mass configurations in the range 10^5 Msun < M < 10^8 Msun with 10^3 randomly distributed points in the parameter space each, comparing the full (FWF) and restricted (RWF) version of the gravitational waveform. We find that the binaries can roughly be separated into two groups: one with low (< ~10^7 Msun) and one with high total masses (> ~10^7 Msun). The RWF errors on the alternative theory parameters are two orders of magnitude higher than the FWF errors for high-mass binaries while almost comparable for low-mass binaries. Due to dilution of the available information, the accuracy of the binary parameters is reduced by factors of a few, except for the luminosity distance which is affected more seriously in the high-mass regime. As an application and to compare our research with previous work, we compute an optimal lower bound on the graviton Compton wavelength which is increased by a factor of ~1.6 when using the FWF.Comment: 33 pages, 37 figure

    Effectiveness and Tolerability of 12-Month Brivaracetam in the Real World: EXPERIENCE, an International Pooled Analysis of Individual Patient Records

    Get PDF
    Efectividad; Tolerabilidad; RegistrosEffectiveness; Tolerability; RecordsEficàcia; Tolerabilitat; RegistresBackground and objective: Real-world evidence studies of brivaracetam (BRV) have been restricted in scope, location, and patient numbers. The objective of this pooled analysis was to assess effectiveness and tolerability of brivaracetam (BRV) in routine practice in a large international population. Methods: EXPERIENCE/EPD332 was a pooled analysis of individual patient records from multiple independent non-interventional studies of patients with epilepsy initiating BRV in Australia, Europe, and the United States. Eligible study cohorts were identified via a literature review and engagement with country lead investigators, clinical experts, and local UCB Pharma scientific/medical teams. Included patients initiated BRV no earlier than January 2016 and no later than December 2019, and had ≥ 6 months of follow-up data. The databases for each cohort were reformatted and standardised to ensure information collected was consistent. Outcomes included ≥ 50% reduction from baseline in seizure frequency, seizure freedom (no seizures within 3 months before timepoint), continuous seizure freedom (no seizures from baseline), BRV discontinuation, and treatment-emergent adverse events (TEAEs) at 3, 6, and 12 months. Patients with missing data after BRV discontinuation were considered non-responders/not seizure free. Analyses were performed for all adult patients (≥ 16 years), and for subgroups by seizure type recorded at baseline; by number of prior antiseizure medications (ASMs) at index; by use of BRV as monotherapy versus polytherapy at index; for patients who switched from levetiracetam to BRV versus patients who switched from other ASMs to BRV; and for patients with focal-onset seizures and a BRV dose of ≤ 200 mg/day used as add-on at index. Analysis populations included the full analysis set (FAS; all patients who received at least one BRV dose and had seizure type and age documented at baseline) and the modified FAS (all FAS patients who had at least one seizure recorded during baseline). The FAS was used for all outcomes other than ≥ 50% seizure reduction. All outcomes were summarised using descriptive statistics. Results: Analyses included 1644 adults. At baseline, 72.0% were 16-49 years of age and 92.2% had focal-onset seizures. Patients had a median (Q1, Q3) of 5.0 (2.0, 8.0) prior antiseizure medications at index. At 3, 6, and 12 months, respectively, ≥ 50% seizure reduction was achieved by 32.1% (n = 619), 36.7% (n = 867), and 36.9% (n = 822) of patients; seizure freedom rates were 22.4% (n = 923), 17.9% (n = 1165), and 14.9% (n = 1111); and continuous seizure freedom rates were 22.4% (n = 923), 15.7% (n = 1165), and 11.7% (n = 1111). During the whole study follow-up, 551/1639 (33.6%) patients discontinued BRV. TEAEs since prior visit were reported in 25.6% (n = 1542), 14.2% (n = 1376), and 9.3% (n = 1232) of patients at 3, 6, and 12 months, respectively. Conclusions: This pooled analysis using data from a variety of real-world settings suggests BRV is effective and well tolerated in routine clinical practice in a highly drug-resistant patient population

    Understanding the role of contrasting urban contexts in healthy aging: an international cohort study using wearable sensor devices (the CURHA study protocol).

    Get PDF
    BACKGROUND: Given the challenges of aging populations, calls have been issued for more sustainable urban re-development and implementation of local solutions to address global environmental and healthy aging issues. However, few studies have considered older adults' daily mobility to better understand how local built and social environments may contribute to healthy aging. Meanwhile, wearable sensors and interactive map-based applications offer novel means for gathering information on people's mobility, levels of physical activity, or social network structure. Combining such data with classical questionnaires on well-being, physical activity, perceived environments and qualitative assessment of experience of places opens new opportunities to assess the complex interplay between individuals and environments. In line with current gaps and novel analytical capabilities, this research proposes an international research agenda to collect and analyse detailed data on daily mobility, social networks and health outcomes among older adults using interactive web-based questionnaires and wearable sensors. METHODS/DESIGN: Our study resorts to a battery of innovative data collection methods including use of a novel multisensor device for collection of location and physical activity, interactive map-based questionnaires on regular destinations and social networks, and qualitative assessment of experience of places. This rich data will allow advanced quantitative and qualitative analyses in the aim to disentangle the complex people-environment interactions linking urban local contexts to healthy aging, with a focus on active living, social networks and participation, and well-being. DISCUSSION: This project will generate evidence about what characteristics of urban environments relate to active mobility, social participation, and well-being, three important dimensions of healthy aging. It also sets the basis for an international research agenda on built environment and healthy aging based on a shared and comprehensive data collection protocol

    Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms

    Get PDF
    In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4&lt;10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable

    Altimetry for the future: Building on 25 years of progress

    Get PDF
    In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion
    corecore