Gravitational-wave astronomy: delivering on the promises Schutz, B. F.
Philosophical transactions - Royal Society. Mathematical, Physical and engineering sciences/Philosophical transactions - Royal Society. Mathematical, physical and engineering sciences,
05/2018, Letnik:
376, Številka:
2120
Journal Article
Recenzirano
Odprti dostop
Now that LIGO and Virgo have begun to detect gravitational-wave events with regularity, the field of gravitational-wave astronomy is beginning to realize its promise. Binary black holes and, very ...recently, binary neutron stars have been observed, and we are already learning much from them. The future, with improved sensitivity, more detectors and detectors like LISA in different frequency bands, has even more promise to open a completely hidden side of the Universe to our exploration.
This article is part of a discussion meeting issue 'The promises of gravitational-wave astronomy'.
We estimate that the moment of inertia of star A in the recently discovered double pulsar system PSR J0737-3039 may be determined after a few years of observation to 610% accuracy. This would enable ...accurate estimates of the radius of the star and the pressure of matter in the vicinity of 1-2 times the nuclear saturation density, which would in turn provide strong constraints on the equation of state of neutron stars and the physics of their interiors.
Type Ia supernovae (SNe Ia) are among the pre-eminent distance ladders for precision cosmology due to their intrinsic brightness, which allows them to be observable at high redshifts. Their ...usefulness as unbiased estimators of absolute cosmological distances, however, depends on accurate understanding of their intrinsic brightness, or anchoring their distance scale. This knowledge is based on calibrating their distances with Cepheids. Gravitational waves from compact binary coalescences, being standard sirens, can be used to validate distances to SNe Ia when both occur in the same galaxy or galaxy cluster. The current measurement of distance by the advanced LIGO and Virgo detector network suffers from large statistical errors (∼50%). However, we find that, using a third-generation gravitational-wave detector network, standard sirens will allow us to measure distances with an accuracy of ∼0.1%-3% for sources within ≤300 Mpc. These are much smaller than the dominant systematic error of ∼5% due to the radial peculiar velocity of host galaxies. Therefore, gravitational-wave observations could soon add a new cosmic distance ladder for an independent calibration of distances to SNe Ia.
Bevacizumab, a humanized monoclonal antibody targeting the vascular endothelial growth factor, is a therapeutic agent used in a variety of neoplasms. We did a meta-analysis of randomized controlled ...trials to fully characterize the arterial thromboembolic events (ATEs) risk with bevacizumab in certain patients' subgroups.
We carried out a literature search on Medline for randomized trial reported from January 1966 to December 2009. Abstracts presented at the American Society of Clinical Oncology held between 2004 and 2009 were also searched for relevant clinical trials. Summary incidence, relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models based on the heterogeneity of included studies.
A total of 13026 patients from 20 randomized trials were included in the meta-analysis. Overall RR for ATE with bevacizumab-based therapy versus controls was 1.46 (95% CI 1.11–1.93, P=0.007). On subgroup analysis, no significant risk differences were found based on the type of malignancy, type of clinical trial (phase II or III trials), type of publication (full papers versus presentations), high- versus low-dose bevacizumab and early versus advanced disease trials. When stratified by concomitant therapies, we found that gemcitabine-based regimens had a significant lower ATE risk compared with non-gemcitabine regimens (P=0.01).
Bevacizumab treatment is associated with a significant increase in the risk of arterial thrombosis. Our results seem to be generalizable to the vast majority of patients receiving bevacizumab in multiple settings.
Gravitational-wave astronomy Schutz, B. F.
Philosophical transactions of the Royal Society of London. Series A: Mathematical, physical, and engineering sciences,
05/2018, Letnik:
376, Številka:
2120
Journal Article
Recenzirano
Now that LIGO and Virgo have begun to detect gravitational-wave events with regularity, the field of gravitational-wave astronomy is beginning to realize its promise. Binary black holes and, very ...recently, binary neutron stars have been observed, and we are already learning much from them. The future, with improved sensitivity, more detectors and detectors like LISA in different frequency bands, has even more promise to open a completely hidden side of the Universe to our exploration.
This article is part of a discussion meeting issue ‘The promises of gravitational-wave astronomy’.
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