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Commercial technologies for notating music pose usage barriers to blind and visually impaired (BVI) musicians because they use graphic user interfaces and only produce visual, print scores. However, more research to date has studied how to make existing scores available in braille or large print rather than understand the needs and workflows of BVI musicians who notate new music. To address this gap, we conducted a six-week remote study in which six BVI musicians with wide-ranging backgrounds wrote original music culminating in a live performance. To create their scores, participants used SoundCells, a product of ongoing co-design and testing with BVI musicians that uses text to generate audio, print, and braille music. Across three interviews, participants offered diverse and nuanced views of how text input could facilitate creative expression. We uncovered how vision ability, music experience, and assistive technology preference affected how music was accessed and traversed. From this research, we provide design recommendations for improving SoundCells' input and output systems, discuss how visual cues embedded in SoundCells' syntax make learning and remembering harder for people who can't view it, and reflect on how our chosen methods resulted in high engagement. [ABSTRACT FROM AUTHOR]

The purpose of this study is to optimize the selection of prophylactic cardioverter defibrillator implantation candidates. Currently, the main criterion for implantation is a low Left Ventricular Ejection Fraction (LVEF) whose specificity is relatively poor. [ABSTRACT FROM PUBLISHER]

Cardiac mapping is a necessary step for accurate diagnostics in cardiology. It generates an activation map of the pathways followed by the electrical depolarization wavefront during the activity of the heart. In some cases, the standard methods to construct activation maps based on the derivatives of the signals may lead to inaccurate results. In this paper, we evaluated a novel Directional Activation Algorithm (DAA) based on EGM analysis. The DAA calculates the time delays between adjacent EGMs and assigns to each a localized propagation vector. We propose a new visual representation of the depolarization wavefront as a field of arrows to facilitate comprehension of propagation pathways; and in addition, we show resultant global activation map. The accuracy of the proposed methodology is compared with known activities obtained from a monodomain, isotrope, Beeler-Reuter model of the atria. [ABSTRACT FROM PUBLISHER]

The calibration strategy of the GLAST Large Area Telescope (LAT) combines analysis of cosmic ray data with accelerator particle beams measurements. An advanced Monte Carlo simulation of the LAT, based on the Geant4 package, was set up to reproduce the LAT response to such radiation and to benchmark the event reconstruction and the background rejection strategy before launch and during operation. To validate the LAT simulation, a massive campaign of beam tests was performed between July and November 2006, in parallel with the LAT integration and test, on the LAT Calibration Unit. This is a detector built with spare flight modules and flight-like readout electronics, which was exposed to a large variety of beams, representing the whole spectrum of the signal that will be detected by the LAT, using the CERN and the GSI accelerator facilities. Beams of photons (0 – 2.5 GeV), electrons (1 – 300 GeV), hadrons (π and p, a few GeV – 100 GeV) and ions (C; Xe, 1.5 GeV/n) were shot through the CU to measure the physical processes taking place in the detector and eventually fine-tune their description in the LAT Monte Carlo simulation. This paper describes the motivations and goals of the test runs, the many different experimental setups used, the measured detector performance and preliminary results of the LAT Monte Carlo validation. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The results of experimental study of magnetic dipole (M1) transitions in highly charged ions of argon (Ar9+, Ar10+, Ar13+ and Ar14+) and krypton (Kr18+ and Kr22+) are presented. The forbidden transitions of the highly charged ions in the visible and near UV range of the photon emission spectra have been measured with accuracy better than 1 ppm. Our measurements for the “coronal lines” are the most accurate yet reported using an EBIT as a spectroscopic source of highly charged ions. These precise wavelength determinations provide a useful test and challenge for atomic structure calculations of many-electron systems. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Single and multiple ionization yields, as a function of projectile energy loss and for forward scattering angles, have been measured for 750 eV positron and 800 eV electron impact on argon. Energy losses extend between zero and approximately 60% of the initial kinetic energy. For positron impact, the percentage of double ionization is found to increase rapidly for the first 80 eV of energy loss, then more slowly until the L-shell threshold. For still higher energy losses the percentage of double ionization saturates at approximately 15%. This is in excellent agreement with photo double ionization measurements. For electron impact, considerably higher amounts of multiple ionization are observed for conditions where the projectile energy loss is large. [ABSTRACT FROM AUTHOR]

Contributions to the ionization cross sections by electron-electron and electron-nuclear interactions are discussed for fast neutral-neutral and ion-atom collisions. The first Born approximation is used to illustrate the relative importance of e-e and e-n processes and how they scale with projectile net charge and number of projectile electrons. New data He - He and He - Ne ionizing collisions is combined with existing atom impact data to compare with the theoretical expectations. [ABSTRACT FROM AUTHOR]

A new scaling law for ionization is presented. Our new model scales the cross sections by Z4/3 and the impact energies by Z2/3, rather than by Z in both cases as suggested by Olson et al. Using available CDW-EIS calculations and experimental data for ionization of helium by fully stripped ions, it is shown that this "modified Z" scaling yields a universal curve throughout the entire energy regime, not just for the region above the cross section maximum. Similar results are obtained for ionization of molecular hydrogen. [ABSTRACT FROM AUTHOR]

The possible similarities and differences between the transmission of slow highly charged ions and light particles, like positrons and electrons, through a single cylindrical, tapered glass capillary with large aspect ratio are studied. We address the question whether the guiding-effect is observable for low intensity positron beams. [ABSTRACT FROM AUTHOR]

In this paper we study the transition from adiabatic to sudden double ionization of valence electrons of atoms by positron impact. Double ionization by a charged particle is usually represented in terms of the shake-off (SO), twostep 1 (TS-1), and two-step 2 (TS-2) mechanisms. The relative contribution of those mechanisms is determined for double ionization of neon. For argon, the SO mechanism is shown to fit the electron impact data but not the positron data. Different post-collision interactions for positron and electron impact or the transition from the adiabatic (TS-1) to the sudden regime (SO) which could imply different interferences between single-and double-interaction mechanisms are possible interpretations for the observed differences. [ABSTRACT FROM AUTHOR]