Tight multi-messenger constraints on the neutron star equation of state from GW170817 and a forward model for kilonova light curve synthesis

We present a rapid analytic framework for predicting kilonova light curves following neutron star (NS) mergers, where the main input parameters are binary-based properties measurable by gravitational wave detectors (chirp mass and mass ratio, orbital inclination) and properties dependent on the nuclear equation of state (tidal deformability, maximum NS mass). This enables synthesis of a kilonova sample for any NS source population, or determination of the observing depth needed to detect a live kilonova given gravitational wave source parameters in low latency. We validate this code, implemented in the public MOSFiT package, by fitting it to GW170817. A Bayes factor analysis overwhelmingly ($B>10^{10}$) favours the inclusion of an additional luminosity source in addition to lanthanide-poor dynamical ejecta during the first day. This is well fit by a shock-heated cocoon model, though differences in the ejecta structure, opacity or nuclear heating rate cannot be ruled out as alternatives. The emission thereafter is dominated by a lanthanide-rich viscous wind. We find the mass ratio of the binary is $q=0.92\pm0.07$ (90% credible interval). We place tight constraints on the maximum stable NS mass, $M_{\rm TOV}=2.17^{+0.08}_{-0.11}$ M$_\odot$. For a uniform prior in tidal deformability, the radius of a 1.4 M$_\odot$ NS is $R_{1.4}\sim 10.7$ km. Re-weighting with a prior based on equations of state that support our credible range in $M_{\rm TOV}$, we derive a final measurement $R_{1.4}=11.06^{+1.01}_{-0.98}$ km. Applying our code to the second gravitationally-detected neutron star merger, GW190425, we estimate that an associated kilonova would have been fainter (by $\sim0.7$ mag at one day post-merger) and declined faster than GW170817, underlining the importance of tuning follow-up strategies individually for each GW-detected NS merger.Comment: Updated to match accepted version in MNRA

Clinical and functional impairment after nonoperative treatment of distal biceps ruptures

© 2018 Journal of Shoulder and Elbow Surgery Board of Trustees Background: Clinical and functional impairment after nonoperative treatment of distal biceps ruptures is not well understood. The goal of this study was to measure patients’ perceived disability, kinematic adjustment, and forearm supination power after nonoperative treatment of distal biceps ruptures. Methods: Fourteen individuals after nonoperative treatment of distal biceps ruptures were matched to a control group of 18 uninjured volunteers. Both groups prospectively completed the Disabilities of the Arm, Shoulder and Hand (DASH), Single Assessment Numerical Evaluation (SANE), and Biceps Disability Questionnaire. Both performed a new timed isotonic supination test that was designed to simulate activities of daily life. The isotonic torque dynamometer measures the supination arc, center of supination arc, torque, angular velocity, and power. Motion analysis quantifies forearm and shoulder contributions to the arc of supination. Results: The nonoperative treated group\u27s DASH (23.2 ± 10.3) and SANE (59.6 ± 16.2) scores demonstrated a clinical meaningful impairment. The control group showed no significant differences in kinematic values between dominant and nondominant arms (P =.854). The nonoperative biceps ruptured arms, compared with their uninjured arms, changed supination motion by decreasing the supination arc (P ≤.036), shifting the center of supination arc to a more pronated position (P ≤.030), and increasing the shoulder contribution to rotation (P ≤.001); despite this adaptation, their average corrected power of supination decreased by 47% (P =.001). Conclusion: Patients should understand that nonoperative treatment for distal biceps ruptures will result in varying degrees of functional loss as measured by the DASH, SANE, and Biceps Disability Questionnaire, change their supination kinematics during repetitive tasks, and that they will lose 47% of their supination power

Calcification, Dissolution and Test Properties of Modern Planktonic Foraminifera From the Central Atlantic Ocean

The mass of well-preserved calcite in planktonic foraminifera shells provides an indication of the calcification potential of the surface ocean. Here we report the shell weight of 8 different abundant planktonic foraminifera species from a set of core-top sediments along the Mid-Atlantic Ridge. The analyses showed that near the equator, foraminifera shells of equivalent size weigh on average 1/3 less than those from the middle latitudes. The carbonate preservation state of the samples was assessed by high resolution X-ray microcomputed tomographic analyses of Globigerinoides ruber and Globorotalia truncatulinoides specimens. The specimen preservation was deemed good and does not overall explain the observed shell mass variations. However, G. ruber shell weights might be to some extent compromised by residual fine debris internal contamination. Deep dwelling species possess heavier tests than their surface-dwelling counterparts, suggesting that the weight of the foraminifera shells changes as a function of the depth habitat. Ambient seawater carbonate chemistry of declining carbonate ion concentration with depth cannot account for this interspecies difference. The results suggest a depth regulating function for plankton calcification, which is not dictated by water column acidity

Nonvanishing quantum corrections to the mass and central charge of the N=2 vortex and BPS saturation

The one-loop quantum corrections to the mass and central charge of the N=2 vortex in 2+1 dimensions are determined using supersymmetry-preserving dimensional regularization by dimensional reduction of the corresponding N=1 model with Fayet-Iliopoulos term in 3+1 dimensions. Both the mass and the central charge turn out to have nonvanishing one-loop corrections which however are equal and thus saturate the Bogomolnyi bound. We explain BPS saturation by standard multiplet shortening arguments, correcting a previous claim in the literature postulating the presence of a second degenerate short multiplet at the quantum level.Comment: 1+16 pages LATeX, 1 figure. v3: minor addition

The critical window for the classical Ramsey-Tur\'an problem

The first application of Szemer\'edi's powerful regularity method was the following celebrated Ramsey-Tur\'an result proved by Szemer\'edi in 1972: any K_4-free graph on N vertices with independence number o(N) has at most (1/8 + o(1)) N^2 edges. Four years later, Bollob\'as and Erd\H{o}s gave a surprising geometric construction, utilizing the isoperimetric inequality for the high dimensional sphere, of a K_4-free graph on N vertices with independence number o(N) and (1/8 - o(1)) N^2 edges. Starting with Bollob\'as and Erd\H{o}s in 1976, several problems have been asked on estimating the minimum possible independence number in the critical window, when the number of edges is about N^2 / 8. These problems have received considerable attention and remained one of the main open problems in this area. In this paper, we give nearly best-possible bounds, solving the various open problems concerning this critical window.Comment: 34 page

Calcification, dissolution and test properties of modern planktonic foraminifera from the central Atlantic Ocean

This research was supported in part by a Royal Society Newton International postdoctoral Fellowship to SZ from the Royal Society of London. JWBR acknowledges funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (grant agreement 805246). We also acknowledge support from U.K. NERC Grant (PUCCA) NE/V011049/1.The mass of well-preserved calcite in planktonic foraminifera shells provides an indication of the calcification potential of the surface ocean. Here we report the shell weight of 8 different abundant planktonic foraminifera species from a set of core-to sediments along the Mid-Atlantic Ridge. The analyses showed that near the equator, foraminifera shells of equivalent size weigh on average 1/3 less than those from the middle latitudes. The carbonate preservation state of the samples was assessed by high resolution X-ray microcomputed tomographic analyses of Globigerinoides ruber and Globorotalia truncatulinoides specimens. The specimen preservation was deemed good and does not overall explain the observed shell mass variations. However, G. ruber shell weights might be to some extent compromised by residual fine debris internal contamination. Deep dwelling species possess heavier tests than their surface-dwelling counterparts, suggesting that the weight of the foraminifera shells changes as a function of the depth habitat. Ambient seawater carbonate chemistry of declining carbonate ion concentration with depth cannot account for this interspecies difference. The results suggest a depth regulating function for plankton calcification, which is not dictated by water column acidity.Publisher PDFPeer reviewe