876 research outputs found

    A sparse reconstruction framework for Fourier-based plane wave imaging

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    International audienceUltrafast imaging based on plane-wave (PW) insonification is an active area of research due to its capability of reaching high frame rates. Among PW imaging methods, Fourier-based approaches have demonstrated to be competitive compared with traditional delay and sum methods. Motivated by the success of compressed sensing techniques in other Fourier imaging modalities, like magnetic resonance imaging, we propose a new sparse regularization framework to reconstruct high-quality ultrasound (US) images. The framework takes advantage of both the ability to formulate the imaging inverse problem in the Fourier domain and the sparsity of US images in a sparsifying domain. We show, by means of simulations, in vitro and in vivo data, that the proposed framework significantly reduces image artifacts, i.e., measurement noise and sidelobes, compared with classical methods, leading to an increase of the image quality

    Les 100 médicaments essentiels. Une approche de médecine interne = 100 essential drugs. An internal medicine approach

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    Déclaration d'intérêts : B. Grosbois : expert pour Actélion, Celgene, Octapharma, Shire. Recherche subventionnée par LFB, Janssen, Genzyme. L. Guillevin : conseiller scientifique Actélion, expert pour (et conférences rémunérées par) GSK, CSL, Roche. L. Guillevin estime cependant n'avoir pas de conflit d'intérêt concernant le présent travail. C. Le Jeunne : expert pour Roche, Sanofi, Novartis, BSM, UCB. Essais thérapeutiques en cours pour Bayer, Pfizer, BMS. P. Morlat : expert pour Gilead, ViiV Health Care, BMS, Abbott, MSD. Ph. Morlat estime cependant n'avoir pas de conflit d'intérêt concernant le présent travail. P. Arlet, O. Aumaitre, J. Cosserat, A. Kettaneh, C. Massot et M. Thomas : aucun conflit d'intérêt.International audiencePURPOSE: Up to 4600 drugs in about 15,000 pharmaceutical forms are available in France which may be a source of misuse with increased occurrence of side effects and costs. While the World Health Organization is encouraging each developed country to work out its own list of essential drugs. The list provided in 2008 by the French Office for the safety of health products has had so far limited impact on practice, so it became obvious to a group of internists to work out a "wise list" of 100 essential medicines covering 95% of the disorders observed in France. METHODS: In June 2011, 10 internists agreed to each provide a list of 100 essential medicines, according to individual experience. In December 2011, a meeting of the participants provided a list as initial consensus and mandated five among them to make proposals for those areas neglected by too many participants or in which needless dispersion of medicines was stated. After internet-facilitated exchanges, an additional list was validated in mild-January 2012. RESULTS: Fifty-four drugs were included in the list of initial consensus (including nine selected by all 10 participants), and 46 in the additional list. So the final "wise list" included 100 drugs. In June 2012, 56 of these drugs were available as generics. This list was compared to those lists set out by five countries in the European Union. CONCLUSION: Generating such a list is feasible. Undoubtedly still non-comprehensive, this list will benefit from the expertise of 14 general practitioners who are currently working out a similar list across France. The final list will be submitted for validation by the French associations of generalist teachers and Internists

    Camera Calibration and Player Localization in SoccerNet-v2 and Investigation of their Representations for Action Spotting

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    peer reviewedSoccer broadcast video understanding has been drawing a lot of attention in recent years within data scientists and industrial companies. This is mainly due to the lucrative potential unlocked by effective deep learning techniques developed in the field of computer vision. In this work, we focus on the topic of camera calibration and on its current limitations for the scientific community. More precisely, we tackle the absence of a large-scale calibration dataset and of a public calibration network trained on such a dataset. Specifically, we distill a powerful commercial calibration tool in a recent neural network architecture on the large-scale SoccerNet dataset, composed of untrimmed broadcast videos of 500 soccer games. We further release our distilled network, and leverage it to provide 3 ways of representing the calibration results along with player localization. Finally, we exploit those representations within the current best architecture for the action spotting task of SoccerNet-v2, and achieve new state-of-the-art performances.DeepSpor

    A compressed beamforming framework for ultrafast ultrasound imaging

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    Classical beamforming methods, based on Delay- And-Sum (DAS) require an extensive number of samples and delay calculations to obtain high-quality images. Compressed Beamforming (CB) proposes an alternative to DAS, based on compressed sensing, which aims at reducing the data rate. However, proposed CB approaches induce a computationally heavy measurement model that hampers their attractiveness for iterative image reconstruction. In this paper, a CB framework, applicable to either radio-frequency or in-phase quadrature data and for both plane wave and diverging wave compounding, is described. The proposed framework exploits a computationally light measurement model which leads to tractable reconstruction. It solves a convex problem and assumes sparsity in a waveletbased model to achieve high-quality image reconstruction from measurements acquired with only few transducer elements

    A virtual imaging platform for multi-modality medical image simulation.

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    International audienceThis paper presents the Virtual Imaging Platform (VIP), a platform accessible at http://vip.creatis.insa-lyon.fr to facilitate the sharing of object models and medical image simulators, and to provide access to distributed computing and storage resources. A complete overview is presented, describing the ontologies designed to share models in a common repository, the workflow template used to integrate simulators, and the tools and strategies used to exploit computing and storage resources. Simulation results obtained in four image modalities and with different models show that VIP is versatile and robust enough to support large simulations. The platform currently has 200 registered users who consumed 33 years of CPU time in 2011

    Anthropocène : Plan B, création de connaissances pour répondre aux enjeux sociétaux de manière soutenable dans les limites planétaires

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    De nombreuses recherches et en particulier celles sur les limites planétaires ont montré que nous dépassons actuellement plusieurs limites globales, ce qui questionne fortement la soutenabilité de nos sociétés contemporaines à forte empreinte écologique. Cette prise de conscience se généralise et a fait croître à une vitesse importante les attentes sociétales de visions alternatives à un futur basé sur le seul progrès technologique et/ou une croissance économique infinie.Nous souhaitons faire face à ces constats et aux attentes qu’ils génèrent, sans greenwashing et sans nous en remettre à une croissance verte que nous savons impossible depuis longtemps et notamment par les travaux commandités par le Club de Rome. Impossibilité qui a été rappelée récemment à notre mémoire par une note de l’UE. Pour cela nous souhaitons engager l’UGA dans la construction, sur le long terme, d’une communauté scientifique transdisciplinaire. Nous proposons de développer des recherches complémentaires et alternatives à celles basées sur la double hypothèse d’un éternel progrès technologique et d’une croissance économique qui serait nécessairement vertueuse sur le plan social. Ces recherches auront pour objectif principal d’appréhender la dimension systémique et complexe des questions de dépassement écologique.Pour cela nous savons que nous pouvons d’ores et déjà appuyer notre démarche sur plusieurs collectifs de personnels et d’étudiants nés spontanément dans différentes structures de l’UGA. Leur diversité de profils et de disciplines constitue un atout précieux pour construire une approche transdisciplinaire. Nous pensons donc qu’il est utile et pertinent d’essayer de fédérer ces initiatives dans une démarche collective commune de production de connaissances

    French Roadmap for complex Systems 2008-2009

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    This second issue of the French Complex Systems Roadmap is the outcome of the Entretiens de Cargese 2008, an interdisciplinary brainstorming session organized over one week in 2008, jointly by RNSC, ISC-PIF and IXXI. It capitalizes on the first roadmap and gathers contributions of more than 70 scientists from major French institutions. The aim of this roadmap is to foster the coordination of the complex systems community on focused topics and questions, as well as to present contributions and challenges in the complex systems sciences and complexity science to the public, political and industrial spheres

    Overview of the current use of levosimendan in France: a prospective observational cohort study

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    Abstract Background Following the results of randomized controlled trials on levosimendan, French health authorities requested an update of the current use and side-effects of this medication on a national scale. Method The France-LEVO registry was a prospective observational cohort study reflecting the indications, dosing regimens, and side-effects of levosimendan, as well as patient outcomes over a year. Results The patients included ( n = 602) represented 29.6% of the national yearly use of levosimendan in France. They were treated for cardiogenic shock ( n = 250, 41.5%), decompensated heart failure ( n = 127, 21.1%), cardiac surgery-related low cardiac output prophylaxis and/or treatment ( n = 86, 14.3%), and weaning from veno-arterial extracorporeal membrane oxygenation ( n = 82, 13.6%). They received 0.18 ± 0.07 µg/kg/min levosimendan over 26 ± 8 h. An initial bolus was administered in 45 patients (7.5%), 103 (17.1%) received repeated infusions, and 461 (76.6%) received inotropes and or vasoactive agents concomitantly. Hypotension was reported in 218 patients (36.2%), atrial fibrillation in 85 (14.1%), and serious adverse events in 17 (2.8%). 136 patients (22.6%) died in hospital, and 26 (4.3%) during the 90-day follow-up. Conclusions We observed that levosimendan was used in accordance with recent recommendations by French physicians. Hypotension and atrial fibrillation remained the most frequent side-effects, while serious adverse event potentially attributable to levosimendan were infrequent. The results suggest that this medication was safe and potentially associated with some benefit in the population studied

    The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

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    Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
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