Regional wall stiffness during acute myocardial ischaemia in the canine left ventricle

In eight anaesthetized closed-chest dogs, acute myocardial ischaemia was produced for 30 to 90 s by inflating a small balloon-catheter, which had been advanced transaortically into the periphery of the left anterior descending coronary artery. Left ventricular high-fidelity pressure measurements and simultaneous angiocardiography were carried out at control and during ischaemia. Left ventricular systolic function was assessed by the left ventricular ejection fraction (EF) as well as by regional shortening in a basal (SH M1), middle (SH M2 and apical (SH M3) segment. Diastolic function was evaluated by the stress-strain relationship using a viscoelastic model. Regional wall stiffness (Kn) was determined in the same three segments (basal, middle and apical), which were used for the evaluation of regional systolic function. For the interindividual comparison of the diastolic stiffness parameters normalization of the strain data was performed by calculating a reference wall circumference (I0) at a common wall stress of 1000 dynes/cm2. During localized myocardial ischaemia left ventricular end-diastolic pressure remained essentially unchanged (7.2 v. 8.3 mm Hg: NS). Left ventricular EF (47 v. 31% P < 0.001), SH M2 (27 v. 14 % P < 0.005) and SH M3 (22 v. 2% P < 0.02) decreased during ischaemia. Kn in the middle (10.0 v. 14.2; P < 0.02) and the apical (9.8 v. 12.7, P < 0.005) segment increased during ischaemia whereas Kn in the non-ischaemic basal segment remained unchanged (9.6 v. 11.8; NS). During ischaemia I0 increased in the middle segment (15.7 v. 17.3 cm; P < 0.005). Our data indicate that during acute ischaemia regional myocardial wall stiffness is increased in the ischaemic segment, but is normal in the non-ischaemic segment. Reference midwall circumference at a common wall stress of 1000 dynes/cm2 is enhanced during acute ischaemia (creep) and corresponds with the increased sarcomere length reported in ischaemic myocardium. Thus, it is suggested that the changes in regional myocardial wall stiffness are related to changes in reference midwall circumference with cree

Moment of Inertia and Quadrupole Response Function of a Trapped Superfluid

We derive an explicit relationship between the moment of inertia and the quadrupole response function of an interacting gas confined in a harmonic trap. The relationship holds for both Bose and Fermi systems and is well suited to reveal the effects of irrotationality of the superfluid motion. Recent experimental results on the scissors mode are used to extract the value of the moment of inertia of a trapped Bose gas and to point out the deviations from the rigid value due to superfluidity.Comment: 6 page

Telemedicine quality and outcomes in stroke: A scientific statement for healthcare professionals from the American Heart Association/American Stroke Association

Purpose - Telestroke is one of the most frequently used and rapidly expanding applications of telemedicine, delivering much-needed stroke expertise to hospitals and patients. This document reviews the current status of telestroke and suggests measures for ongoing quality and outcome monitoring to improve performance and to enhance delivery of care. Methods - A literature search was undertaken to examine the current status of telestroke and relevant quality indicators. The members of the writing committee contributed to the review of specific quality and outcome measures with specific suggestions for metrics in telestroke networks. The drafts were circulated and revised by all committee members, and suggestions were discussed for consensus. Results - Models of telestroke and the role of telestroke in stroke systems of care are reviewed. A brief description of the science of quality monitoring and prior experience in quality measures for stroke is provided. Process measures, outcomes, tissue-type plasminogen activator use, patient and provider satisfaction, and telestroke technology are reviewed, and suggestions are provided for quality metrics. Additional topics include licensing, credentialing, training, and documentation

A search for radio emission from double-neutron star merger GW190425 using Apertif

ContextDetection of the electromagnetic emission from coalescing binary neutron stars (BNS) is important for understanding the merger and afterglow. Aims. We present a search for a radio counterpart to the gravitational-wave (GW) source GW190425, a BNS merger, using Apertif on the Westerbork Synthesis Radio Telescope (WSRT). MethodsWe observed a field of high probability in the associated localisation region for three epochs at ΔT\ue2€., =\ue2€., 68, 90, 109 d post merger. We identified all sources that exhibit flux variations consistent with the expected afterglow emission of GW190425. We also looked for possible transients. These are sources that are only present in one epoch. In addition, we quantified our ability to search for radio afterglows in the fourth and future observing runs of the GW detector network using Monte Carlo simulations. ResultsWe found 25 afterglow candidates based on their variability. None of these could be associated with a possible host galaxy at the luminosity distance of GW190425. We also found 55 transient afterglow candidates that were only detected in one epoch. All of these candidates turned out to be image artefacts. In the fourth observing run, we predict that up to three afterglows will be detectable by Apertif. ConclusionsWhile we did not find a source related to the afterglow emission of GW190425, the search validates our methods for future searches of radio afterglows

A bright, high rotation-measure FRB that skewers the M33 halo

We report the detection of a bright fast radio burst, FRB\,191108, with Apertif on the Westerbork Synthesis Radio Telescope (WSRT). The interferometer allows us to localise the FRB to a narrow 5\arcsec\times7\arcmin ellipse by employing both multibeam information within the Apertif phased-array feed (PAF) beam pattern, and across different tied-array beams. The resulting sight line passes close to Local Group galaxy M33, with an impact parameter of only 18\,kpc with respect to the core. It also traverses the much larger circumgalactic medium of M31, the Andromeda Galaxy. We find that the shared plasma of the Local Group galaxies could contribute $\sim$10\% of its dispersion measure of 588\,pc\,cm$^{-3}$. FRB\,191108 has a Faraday rotation measure of +474\,$\pm\,3$\,rad\,m$^{-2}$, which is too large to be explained by either the Milky Way or the intergalactic medium. Based on the more moderate RMs of other extragalactic sources that traverse the halo of M33, we conclude that the dense magnetised plasma resides in the host galaxy. The FRB exhibits frequency structure on two scales, one that is consistent with quenched Galactic scintillation and broader spectral structure with $\Delta\nu\approx40$\,MHz. If the latter is due to scattering in the shared M33/M31 CGM, our results constrain the Local Group plasma environment. We found no accompanying persistent radio sources in the Apertif imaging survey data

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter