Abstract
Aims
Coronary computed tomography angiography (CTA) has emerged as a non-invasive diagnostic method for patients with suspected coronary artery disease, but its usefulness in patients with ...complex coronary artery disease remains to be investigated. The present study sought to determine the agreement between separate heart teams on treatment decision-making based on either coronary CTA or conventional angiography.
Methods and results
Separate heart teams composed of an interventional cardiologist, a cardiac surgeon, and a radiologist were randomized to assess the coronary artery disease with either coronary CTA or conventional angiography in patients with de novo left main or three-vessel coronary artery disease. Each heart team, blinded for the other imaging modality, quantified the anatomical complexity using the SYNTAX score and integrated clinical information using the SYNTAX Score II to provide a treatment recommendations based on mortality prediction at 4 years: coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or equipoise between CABG and PCI. The primary endpoint was the agreement between heart teams on the revascularization strategy. The secondary endpoint was the impact of fractional flow reserve derived from coronary CTA (FFRCT) on treatment decision and procedural planning. Overall, 223 patients were included. A treatment recommendation of CABG was made in 28% of the cases with coronary CTA and in 26% with conventional angiography. The agreement concerning treatment decision between coronary CTA and conventional angiography was high (Cohen’s kappa 0.82, 95% confidence interval 0.74–0.91). The heart teams agreed on the coronary segments to be revascularized in 80% of the cases. FFRCT was available for 869/1108 lesions (196/223 patients). Fractional flow reserve derived from coronary CTA changed the treatment decision in 7% of the patients.
Conclusion
In patients with left main or three-vessel coronary artery disease, a heart team treatment decision-making based on coronary CTA showed high agreement with the decision derived from conventional coronary angiography suggesting the potential feasibility of a treatment decision-making and planning based solely on this non-invasive imaging modality and clinical information.
Trial registration number
NCT02813473.
The respective roles of oral anticoagulation or antiplatelet therapy following transcatheter aortic valve implantation (TAVI) remain debated. ATLANTIS is an international, randomized, open-label, ...superiority trial comparing apixaban to the standard of care.
After successful TAVI, 1500 patients were randomized (1:1) to receive apixaban 5 mg (2.5 mg if impaired renal function or concomitant antiplatelet therapy) (n = 749) twice daily, or standard of care (n = 751). Randomization was stratified by the need for chronic anticoagulation therapy. Standard-of-care patients received a vitamin K antagonist (VKA) (Stratum 1) or antiplatelet therapy (Stratum 2) if there was an indication for anticoagulation or not, respectively. The primary endpoint was the composite of death, myocardial infarction, stroke or transient ischaemic attack, systemic embolism, intracardiac or bioprosthesis thrombosis, deep vein thrombosis or pulmonary embolism, and life-threatening, disabling, or major bleeding over 1-year follow-up. The primary safety endpoint was major, disabling, or life-threatening bleeding. The primary outcome occurred in 138 (18.4%) and 151 (20.1%) patients receiving apixaban or standard of care, respectively hazard ratio (HR) 0.92; 95% confidence interval (CI) 0.73-1.16 and there was no evidence of interaction between treatment and stratum (Pinteraction = 0.57). The primary safety endpoint was similar in both groups (HR 1.02; 95% CI 0.72-1.44). In Stratum 1 (n = 451), an exploratory analysis showed no difference for all endpoints between apixaban and VKA. In Stratum 2 (n = 1049), the primary outcome and primary safety endpoint did not differ, but obstructive valve thrombosis was reduced with apixaban vs. antiplatelet therapy (HR 0.19; 95% CI 0.08-0.46), while a signal of higher non-cardiovascular mortality was observed with apixaban.
After TAVI, apixaban was not superior to the standard of care, irrespective of an indication for oral anticoagulation.
Cette thèse propose une nouvelle méthode pour fournir une connexion réseau à des véhicules au cours de trajets prédéterminés (trains, métros, autobus urbains, etc.). La communication entre le ...véhicule et l'infrastructure réseau est basée uniquement sur la technologie WiFi. Les contributions de ce travail sont d'une part la conception d'une méthode pour réaliser le handover horizontal (entre bornes WiFi), et d'autre part la modélisation et l'analyse de topologies pour le réseau d'infrastructure (réseau backbone plus réseau d'accès WiFi) déployé sur la trajectoire du véhicule. Dans une première partie, nous proposons une méthode, appelée Spiderman Handover, pour réaliser le handover horizontal d'un réseau en mouvement (embarqué dans le véhicule) et une procédure de mise à jour des informations de routage (couche 2 OSI) lors du handover. Nous évaluons notre proposition par simulation et validons nos résultats par des mesures expérimentales. Dans une deuxième partie, nous étudions théoriquement les paramètres de plusieurs familles de topologies du type Chordal pour le réseau backbone construit sur un réseau d'accès linéaire. A partir de la comparaison de ces paramètres, nous proposons une topologie backbone issue de la combinaison de deux topologies Chordal. Cette topologie fournit un bon compromis entre coût du déploiement, nombre de sauts nécessaires pour atteindre la passerelle du réseau et résilience raisonnable. Enfin, nous évaluons l'intégration de la topologie proposée pour le réseau d'infrastructure avec le système handover par des simulations. Les résultats présentés suggèrent que l'algorithme de handover proposé fonctionne correctement sur le réseau d'infrastructure proposé. Cela permet la garantie d'une connexion continue aux passagers à bord des trains, métros ou autobus urbains.
The High Cadence Transient Survey (HiTS) aims to discover and study transient objects with characteristic timescales between hours and days, such as pulsating, eclipsing and exploding stars. This ...survey represents a unique laboratory to explore large etendue observations from cadences of about 0.1 days and to test new computational tools for the analysis of large data. This work follows a fully \textit{Data Science} approach: from the raw data to the analysis and classification of variable sources. We compile a catalog of \({\sim}15\) million object detections and a catalog of \({\sim}2.5\) million light-curves classified by variability. The typical depth of the survey is \(24.2\), \(24.3\), \(24.1\) and \(23.8\) in \(u\), \(g\), \(r\) and \(i\) bands, respectively. We classified all point-like non-moving sources by first extracting features from their light-curves and then applying a Random Forest classifier. For the classification, we used a training set constructed using a combination of cross-matched catalogs, visual inspection, transfer/active learning and data augmentation. The classification model consists of several Random Forest classifiers organized in a hierarchical scheme. The classifier accuracy estimated on a test set is approximately \(97\%\). In the unlabeled data, \(3\,485\) sources were classified as variables, of which \(1\,321\) were classified as periodic. Among the periodic classes we discovered with high confidence, 1 \(\delta\)-scutti, 39 eclipsing binaries, 48 rotational variables and 90 RR-Lyrae and for the non-periodic classes we discovered 1 cataclysmic variables, 630 QSO, and 1 supernova candidates. The first data release can be accessed in the project archive of HiTS.
We report the discovery of distant RR Lyrae stars, including the most distant known in the Milky Way, using data taken in the \(g-\)band with the Dark Energy Camera as part of the High cadence ...Transient Survey (HiTS; 2014 campaign). We detect a total of 173 RR Lyrae stars over a ~120 deg^2 area, including both known RR Lyrae and new detections. The heliocentric distances d_H of the full sample range from 9 to >200 kpc, with 18 of them beyond 90 kpc. We identify three sub-groups of RR Lyrae as members of known systems: the Sextans dwarf spheroidal galaxy, for which we report 46 new discoveries, and the ultra-faint dwarf galaxies Leo IV and Leo V. Following an MCMC methodology, we fit spherical and ellipsoidal profiles of the form rho(R) ~ R^n to the radial density distribution of RR Lyrae in the Galactic halo. The best fit corresponds to the spherical case, for which we obtain a simple power-law index of n=-4.17^{+0.18}_{-0.20}, consistent with recent studies made with samples covering shorter distances. The pulsational properties of the outermost RR Lyrae in the sample (d_H>90 kpc) differ from the ones in the halo population at closer distances. The distribution of the stars in a Period-Amplitude diagram suggest they belong to Oosterhoff-intermediate or Oosterhoff II groups, similar to what is found in the ultra-faint dwarf satellites around the Milky Way. The new distant stars discovered represent an important addition to the few existing tracers of the Milky Way potential in the outer halo.
During the analysis of RR Lyrae stars discovered in the High cadence Transient Survey (HiTS) taken with the Dark Energy Camera at the 4-m telescope at Cerro Tololo Inter-American Observatory, we ...found a group of three very distant, fundamental mode pulsator RR Lyrae (type ab). The location of these stars agrees with them belonging to the Leo V ultra-faint satellite galaxy, for which no variable stars have been reported to date. The heliocentric distance derived for Leo V based on these stars is 173 +/- 5 kpc. The pulsational properties (amplitudes and periods) of these stars locate them within the locus of the Oosterhoff II group, similar to most other ultra-faint galaxies with known RR Lyrae stars. This serendipitous discovery shows that distant RR Lyrae stars may be used to search for unknown faint stellar systems in the outskirts of the Milky Way.
In this paper, we propose a new mechanism, called the Spiderman Handover, for enabling Wi-Fi technology to support high speed mobility. It introduces two new 802.11 operational modes: the Spiderman ...mode and the Wireless Switch Access Point mode. We describe its operation, highlighting the Spiderman Handover and the Gratuitous ARP Loop routing update procedure as key elements for providing seamless horizontal handover for high-speed vehicles such as trains. We discuss and evaluate its operation theoretically and by means of simulation, concluding that the proposed mechanism is able to provide track-side connectivity with virtually no packet loss while keeping the observed latency invariant to the handover frequency.
Introducción: En Chile el primer caso de COVID-19 fue diagnosticado el tres de marzo del 2020 y el día dieciocho del mismo mes el presidente decreto estado de catástrofe, por lo que las clases a ...nivel escolar y universitario pasaron de la presencialidad a la virtualidad. El presente estudio tiene como objetivo conocer el nivel de satisfacción de las clases virtuales de los estudiantes de Educación Física. Metodología: Cuantitativa, no experimental, transversal. La muestra estuvo constituida por 542 alumnos de Educación Física de diferentes casas de estudio de Chile. Se adaptó y validó la escala Satisfacción clases online. Resultados: existen diferencias significativas comparando las asignaturas teóricas y prácticas, siendo mejor valoradas las cátedras teóricas. También se encontraron diferencias por sexo, donde los varones poseen una percepción más negativa sobre las clases virtuales y al comparar por curso, los alumnos de primer año poseen una percepción más positiva sobre las clases virtuales en relación con los cursos superiores. Conclusiones: existe una resistencia por parte de los alumnos a las clases virtuales en la Educación Física, pues, si bien se encontraron diferencias significativas entre las asignaturas teóricas y prácticas, los valores siempre estuvieron alrededor de 3 en una escala de 1 a 5. Se hacen necesarias futuras investigaciones con otras variables como actividad física, niveles de estrés y estrategias para la enseñanza de la Educación Física virtual.
Abstract. Introduction: In Chile the first case of COVID-19 was diagnosed on March 3, 2020 and on the eighteenth of the same month the president decreed state of catastrophe, so that classes at school and university level went from the presence to the virtuality. The present study aims to know the level of satisfaction of the virtual classes of the students of Physical Education. Methodology: Quantitative, non experimental, transversal. The sample consisted of 542 students of Physical Education from different study houses in Chile. The Satisfaction scale online classes was adapted and validated. Results: there are significant differences comparing theoretical and practical subjects, with theoretical chairs being better valued. Differences were also found by sex, where males have a more negative perception about virtual classes and when comparing by course, freshmen have a more positive perception about virtual classes in relation to higher courses. Conclusions: there is a resistance on the part of students to virtual classes in Physical Education, because, although significant differences were found between the theoretical and practical subjects, values were always around 3 on a scale of 1 to 5. Future research with other variables such as physical activity, stress levels and strategies for the teaching of Virtual Physical Education are necessary.
PDF
