Critical appraisal of technologies to assess electrical activity during atrial fibrillation: a position paper from the European Heart Rhythm Association and European Society of Cardiology Working Group on eCardiology in collaboration with the Heart Rhythm Society, Asia Pacific Heart Rhythm Society, Latin American Heart Rhythm Society and Computing in Cardiology

We aim to provide a critical appraisal of basic concepts underlying signal recording and processing technologies applied for (i) atrial fibrillation (AF) mapping to unravel AF mechanisms and/or identifying target sites for AF therapy and (ii) AF detection, to optimize usage of technologies, stimulate research aimed at closing knowledge gaps, and developing ideal AF recording and processing technologies. Recording and processing techniques for assessment of electrical activity during AF essential for diagnosis and guiding ablative therapy including body surface electrocardiograms (ECG) and endo- or epicardial electrograms (EGM) are evaluated. Discussion of (i) differences in uni-, bi-, and multi-polar (omnipolar/Laplacian) recording modes, (ii) impact of recording technologies on EGM morphology, (iii) global or local mapping using various types of EGM involving signal processing techniques including isochronal-, voltage- fractionation-, dipole density-, and rotor mapping, enabling derivation of parameters like atrial rate, entropy, conduction velocity/direction, (iv) value of epicardial and optical mapping, (v) AF detection by cardiac implantable electronic devices containing various detection algorithms applicable to stored EGMs, (vi) contribution of machine learning (ML) to further improvement of signals processing technologies. Recording and processing of EGM (or ECG) are the cornerstones of (body surface) mapping of AF. Currently available AF recording and processing technologies are mainly restricted to specific applications or have technological limitations. Improvements in AF mapping by obtaining highest fidelity source signals (e.g. catheter–electrode combinations) for signal processing (e.g. filtering, digitization, and noise elimination) is of utmost importance. Novel acquisition instruments (multi-polar catheters combined with improved physical modelling and ML techniques) will enable enhanced and automated interpretation of EGM recordings in the near future

Latitude gradient influences the age of onset of rheumatoid arthritis : a worldwide survey

The age of onset of rheumatoid arthritis (RA) is an important outcome predictor. Northern countries report an age of RA onset of around 50 years, but apparently, variability exists across different geographical regions. The objective of the present study is to assess whether the age of onset of RA varies across latitudes worldwide. In a proof-of-concept cross-sectional worldwide survey, rheumatologists from preselected cities interviewed 20 consecutive RA patients regarding the date of RA onset (RAO, when the patient first noted a swollen joint). Other studied variables included location of each city, rheumatologist settings, latitudes (10A degrees increments, south to north), longitudes (three regions), intracountry consistency, and countries' Inequality-adjusted Human Development Index (IHDI). Data from 2481 patients (82% females) were obtained from 126 rheumatologists in 77 cities of 41 countries. Worldwide mean age of RAO was 44 +/- 14 years (95% CI 44-45). In 28% of patients, RA began before age 36 years and before age 46 years in 50% of patients. RAO was 8 years earlier around the Tropic of Cancer when compared with northern latitudes (p <0.001, 95% CI 3.5-13). Multivariate analysis showed that females, western cities, and latitudes around the Tropic of Cancer are associated with younger age of RAO (R (2) 0.045, p <0.001). A positive correlation was found between the age of RAO and IHDI (r = 0.7, p <0.01, R (2) 0.5). RA often begins at an early age and onset varies across latitudes worldwide. We postulate that countries' developmental status and their geographical and geomagnetic location influence the age of RAO.Peer reviewe

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe

Progress in track-mounted heliostat

A novel concept is presented for a track-mounted heliostat for central receiver plants, intended to be manufacturable at low cost and to reach an installed cost of ~ $60 /m2 when implemented in high volume. Cost reduction is achieved by using steel in the structurally most efficient form of spaceframe structures. These spread the load broadly, halving the quantity of steel per square meter of reflecting area compared to a conventional post /fishbone heliostat design . The structure is turned in azimuth on wheels on a large diameter ground track, eliminating the need for an expensive, heavy slewing bearing. A preliminary finite-element design of a 22 m2 heliostat with spaceframe azimuth and elevation structures has a total steel mass of mass of 15 kg/m2 supporting 10 kg/m2 of glass reflectors and survives 145 km/h wind. Here we report of field tests of engineering performance of a first prototype of the lower, azimuth spaceframe mounted on a 7 m diameter concrete track. The moving structure with wheels and drive weighs 11 kg/m2 and has a measured lowest resonant frequency of 7.5 Hz, when loaded with a simulated elevation structure. The prototype incorporates inclinometers which measure alignment of the azimuth and elevation axes to better than 0.2 mrad. Absolute azimuth rotation angle measured via an incremental encoder on the drive motor encoder and metal reference bars in the concrete track was found to be accurate to 0.35 mrad. Combining the tip/tilt, azimuth rotation and servo errors in quadrature gives a total of 0.49 mrad in tracker orientation, providing encouragement that our full heliostat system target of 1 mrad RMS pointing accuracy (double the orientation accuracy) should be achievable. © 2020 American Institute of Physics Inc.. All rights reserved.12 month embargo; published online: 11 December 2020This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

EHRA expert consensus statement and practical guide on optimal implantation technique for conventional pacemakers and implantable cardioverter-defibrillators: endorsed by the Heart Rhythm Society (HRS), the Asia Pacific Heart Rhythm Society (APHRS), and the Latin-American Heart Rhythm Society (LAHRS)

Item does not contain fulltextWith the global increase in device implantations, there is a growing need to train physicians to implant pacemakers and implantable cardioverter-defibrillators. Although there are international recommendations for device indications and programming, there is no consensus to date regarding implantation technique. This document is founded on a systematic literature search and review, and on consensus from an international task force. It aims to fill the gap by setting standards for device implantation