307 research outputs found
Updates on His bundle pacing: The road more traveled lately
His bundle pacing (HBP) has continued to evolve over the past decade and has started to become a global phenomenon. Evidence is mounting of its clinical benefits as compared to both right ventricular and left ventricular pacing. In this paper, we review recent data in support of His bundle pacing and some of the challenges facing us as we advocate its increasing role in clinical practice
The R-Process Alliance: A Comprehensive Abundance Analysis of HD 222925, a Metal-Poor Star with an Extreme R-Process Enhancement of [Eu/H] = -0.14
We present a detailed abundance analysis of the bright (V = 9.02), metal-poor
([Fe/H] = -1.47 +/- 0.08) field red horizontal-branch star HD 222925, which was
observed as part of an ongoing survey by the R-Process Alliance. We calculate
stellar parameters and derive abundances for 46 elements based on 901 lines
examined in a high-resolution optical spectrum obtained using the Magellan
Inamori Kyocera Echelle spectrograph. We detect 28 elements with 38 <= Z <= 90;
their abundance pattern is a close match to the Solar r-process component. The
distinguishing characteristic of HD 222925 is an extreme enhancement of
r-process elements ([Eu/Fe] = +1.33 +/- 0.08, [Ba/Eu] = -0.78 +/- 0.10) in a
moderately metal-poor star, so the abundance of r-process elements is the
highest ([Eu/H] = -0.14 +/- 0.09) in any known r-process-enhanced star. The
abundance ratios among lighter (Z <= 30) elements are typical for metal-poor
stars, indicating that production of these elements was dominated by normal
Type II supernovae, with no discernible contributions from Type Ia supernovae
or asymptotic giant branch stars. The chemical and kinematic properties of HD
222925 suggest it formed in a low-mass dwarf galaxy, which was enriched by a
high-yield r-process event before being disrupted by interaction with the Milky
Way.Comment: Accepted for publication in the Astrophysical Journal (17 pages, 4
figures, 3 tables
Myasthenie - spondylarthropathies: association fortuite ? A propos d’un cas et revue de la littérature
Propos Nous rapportons le cas d’un patient atteint d’une myasthénie associée à une spondylarthropathie. Cette observation est originale de part sa rareté, six cas seulement on été rapportés dans la littérature et le problème que pose cette association : est ce qu’elle est fortuite ou impliquerait-elle d’autres facteurs génétiques qui restent à prouver ?Observation Monsieur J.H. âgé de 32 ans, aux antécédents de myasthénie depuis 2002, était hospitalisé en avril 2004 pour polyarthrite chronique bilatérale et asymétrique évoluant depuis un an, touchant le poignet gauche, les inter phalangiennes proximales des 3ème et 5ème doigts droits et le genou droit associées à des talalgiesbilatérales et une douleur des articulations sacro-iliaques. La biologie montrait un syndrome inflammatoire modéré, des facteurs rhumatoïdes faiblement positifs et un typage HLA B7 et B17. Le bilan radiologiquemontrait une arthrite des mains, une enthésite calcanéenne et permettait de suspecter une sacro-iliite bilatérale qui était confirmée par un scanner. L’évolution était bonne sous anti- inflammatoires nonstéroïdiens pendant 6 mois. Il consulte en janvier 2006 pour le même tableau associé à une sècheresse buccale et oculaire. Le bilan trouvait une VS à 20, des facteurs rhumatoïdes faiblement positifs mais desAAN positifs à un taux 1/160 homogènes avec des anti SSA. Les radiographies standard montraient une carpite stade II gauche. L’examen ophtalmologique a confirmé le syndrome sec oculaire. La biopsie des glandes salivaires accessoires a montré un syndrome de Gougerot Sjögren grade 2 de Shisholm
The R-Process Alliance: Chemical Abundances for a Trio of R-Process-Enhanced Stars -- One Strong, One Moderate, One Mild
We present detailed chemical abundances of three new bright (V ~ 11),
extremely metal-poor ([Fe/H] ~ -3.0), r-process-enhanced halo red giants based
on high-resolution, high-S/N Magellan/MIKE spectra. We measured abundances for
20-25 neutron-capture elements in each of our stars. J1432-4125 is among the
most r-process rich r-II stars, with [Eu/Fe]= +1.44+-0.11. J2005-3057 is an r-I
star with [Eu/Fe] = +0.94+-0.07. J0858-0809 has [Eu/Fe] = +0.23+-0.05 and
exhibits a carbon abundance corrected for evolutionary status of [C/Fe]_corr =
+0.76, thus adding to the small number of known carbon-enhanced r-process
stars. All three stars show remarkable agreement with the scaled solar
r-process pattern for elements above Ba, consistent with enrichment of the
birth gas cloud by a neutron star merger. The abundances for Sr, Y, and Zr,
however, deviate from the scaled solar pattern. This indicates that more than
one distinct r-process site might be responsible for the observed
neutron-capture element abundance pattern. Thorium was detected in J1432-4125
and J2005-3057. Age estimates for J1432-4125 and J2005-3057 were adopted from
one of two sets of initial production ratios each by assuming the stars are
old. This yielded individual ages of 12+-6 Gyr and 10+-6 Gyr, respectively.Comment: 30 pages, includes a long table, 5 figure
Microwave-Induced Chemotoxicity of Polydopamine-Coated Magnetic Nanocubes
Polydopamine-coated FeCo nanocubes (PDFCs) were successfully synthesized and tested under microwave irradiation of 2.45 GHz frequency and 0.86 W/cm2 power. These particles were found to be non-toxic in the absence of irradiation, but gained significant toxicity upon irradiation. Interestingly, no increase in relative heating rate was observed when the PDFCs were irradiated in solution, eliminating nanoparticle (NP)-induced thermal ablation as the source of toxicity. Based on these studies, we propose that microwave-induced redox processes generate the observed toxicity
Explainable Artificial Intelligence in communication networks: A use case for failure identification in microwave networks
Artificial Intelligence (AI) has demonstrated superhuman capabilities in solving a significant number of tasks, leading to widespread industrial adoption. For in-field network-management application, AI-based solutions, however, have often risen skepticism among practitioners as their internal reasoning is not exposed and their decisions cannot be easily explained, preventing humans from trusting and even understanding them. To address this shortcoming, a new area in AI, called Explainable AI (XAI), is attracting the attention of both academic and industrial researchers. XAI is concerned with explaining and interpreting the internal reasoning and the outcome of AI-based models to achieve more trustable and practical deployment. In this work, we investigate the application of XAI for network management, focusing on the problem of automated failure-cause identification in microwave networks. We first introduce the concept of XAI, highlighting its advantages in the context of network management, and we discuss in detail the concept behind Shapley Additive Explanations (SHAP), the XAI framework considered in our analysis. Then, we propose a framework for a XAI-assisted ML-based automated failure-cause identification in microwave networks, spanning model's development and deployment phases. For the development phase, we show how to exploit SHAP for feature selection and how to leverage SHAP to inspect misclassified instances during model's development process, and how to describe model's global behavior based on SHAP's global explanations. For the deployment phase, we propose a framework based on predictions uncertainty to detect possibly wrong predictions that will be inspected through XAI
Rheological Properties of Clay Suspensions Treated by Hydrocyclone Process
Suspensions of bentonite clays are usually employed at industrial scale in different processes as drilling fluids as well as adsorbents for removing pollutants in muds or natural waters. For these purposes, avoiding the gravitational settling of the particles is a requirement for achieving a high efficiency and a low cost operation. Unfortunately, the clays in natural deposits are usually mixed with particles of other minerals with similar density, making difficult the separation process by usual gravitational methods. Among the most efficient and lowest cost processes, the separation by hydrocyclone is preferred because of a number of advantages at the industrial scale. In this work we verify, by different experimental methods, the efficiency of this wet separation process for removing impurities in a raw bentonite mineral, and at the same time to transform a calcium bentonite in a sodium one by dissolving sodium carbonate in the liquid phase of the hidrocyclone. Afterwards, we checked by using rheological measurements the best protocol for the preparation of the suspension. We studied the rheological behaviour of clay suspensions, with different degree of impurities removal and with different solid concentration, in order to determine the minimal conditions for obtaining bentonite suspensions that do not suffer from gravitational settling during a long period of time. For this purpose, we investigated the deformation and flow of different suspensions, under steady state and oscillatory shear, and determined when they developed a high enough yield stress and an appropriate elastic response to avoid particle settling. We explain the results in view of the energy of interaction between the different surfaces (faces, edges) of the clay platelets, which favours the formation of a soft gel in which the particles are entrapped in loose flocculi that extent along all the volume of the suspensions.This study was supported by
project FIS2013-41821-R (Plan Nacional de Investigación
CientÃfica, Desarrollo e Innovación Tecnológica, Ministerio
de EconomÃa y Competitividad, Spain, co-funded
by ERDF, European Union). Mariem Mekni Abrougui
acknowledges financial support from Tunisian Goverment
(fellowship program) and UE (Erasmus program) for her
stays in the University of Granada
Outcome of the ‘Drip-and-Ship’ Paradigm among Patients with Acute Ischemic Stroke: Results of a Statewide Study
www.karger.com/cee This is an Open Access article licensed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License (www.karger.com/OA-license), applicable to the online version of the article only. Distribution for non-commercial purposes only.
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