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A huge amount of research is devoted today to determine good indicators applicable on time series obtained from real systems that may anticipate a change in its behaviour [1] , [2] . A well-established indicator is the so-called "critical slowing down" (CSD). CSD is the asymptotic growth of the of the relaxation time of a kicked dynamical system when it is approaching a bifurcation [3] . In this contribution, we address the question whether CSD is always a good indicator of an incoming bifurcation in a system where a parameter is linearly changing in time. We answer by presenting a laser system with a time swept pump where CSD appears only after the bifurcation has already occurred, hence when it is too late to reverse its behavioural change. Furthermore, we show experimentally that a perturbation in the accessible control parameter is unable to provide any indication, nor on the occurrence of CSD nor on the bifurcation crossing.

We develop a theoretical model for a unidirectional ring laser consisting of an isotropic active medium inside a cavity containing a birefringent Kerr cell. We analyze the dynamical behavior of the system as we modulate the voltage applied to the Kerr cell. We discuss the bifurcation diagram and we study the regions of control parameter space where it becomes possible to observe and predict extreme events.

IntroductionExpanded-criteria donors (ECDs) are used to reduce the shortage of kidneys for transplantation. However, kidneys from ECDs are associated with an increased risk of delayed graft function (DGF), a risk factor for allograft loss and mortality. HYPOREME will be a multicentre randomised controlled trial (RCT) comparing targeted hypothermia to normothermia in ECDs, in a country where the use of machine perfusion for organ storage is the standard of care. We hypothesise that hypothermia will decrease the incidence of DGF.Methods and analysisHYPOREME is a multicentre RCT comparing the effect on kidney function in recipients of targeted hypothermia (34°C–35°C) and normothermia (36.5°C–37.5°C) in the ECDs. The temperature intervention starts from randomisation and is maintained until aortic clamping in the operating room. We aim to enrol 289 ECDs in order to analyse the kidney function of 516 recipients in the 53 participating centres. The primary outcome is the occurrence of DGF in kidney recipients, defined as a requirement for renal replacement therapy within 7 days after transplantation (not counting a single session for hyperkalemia during the first 24 hours). Secondary outcomes include the proportion of patients with individual organs transplanted in each group; the number of organs transplanted from each ECD and the vital status and kidney function of the recipients 7 days, 28 days, 3 months and 1 year after transplantation. An interim analysis is planned after the enrolment of 258 kidney recipients.Ethics and disseminationThe trial was approved by the ethics committee of the French Intensive Care Society (CE-SRLF-16-07) on 26 April 2016 and by the competent French authorities on 20 April 2016 (Comité de Protection des Personnes-TOURS-Région Centre-Ouest 1, registration #2016-S3). Findings will be published in peer-reviewed journals and presented during national and international scientific meetings.Trial registration numberNCT03098706.

We study the dynamical behavior of a model commonly used to describe the infection of mice due to hantavirus (and, therefore, its possibility of propagation into human populations) when a parameter is changed in time. In particular, we study the situation when the ecological conditions (e.g., climate benignity, food availability, and so on) change periodically in time. We show that the density of infected mice increases abruptly as the parameter crosses a critical value. We correlate such a situation with the observed sudden outbreaks of hantavirus. Finally, we discuss the possibility of preventing a hantavirus epidemic. Fil: Torre, Maria Susana. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física Arroyo Seco; Argentina Fil: Acquaviva, Anaïs. Université de la Nouvelle Calédonie; Francia Fil: Boyer, Jean-Marc. Université de la Nouvelle Calédonie; Francia Fil: Tredicce, Jorge Raul. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Data scientist a ete declare le travail le plus « sexy » du xxie siecle par la Harvard Business Review. En quoi l’exploitation des donnees de masse peut-elle revolutionner les services financiers et leurs tarifications ? Quels sont les freins au deploiement du big data et quelles sont les pressions ? En depit de nombreuses limites en France, des opportunites apparaissent, qu’il faut saisir aujourd’hui.Classification JEL : G20, L11, L86, L96.

There is always a special interest in trying to predict transitions, crisis, social revolutions, catastrophic events like the end of the world and, nowadays judging by the number of spam messages coming from clairvoyants, we strongly believe that the interest in predicting events of every type is growing fast. Almost always catastrophic events are produced when a bifurcation occurs in a dynamical system. Examples in optics can be the laser threshold, bistability, optical rogue waves, instabilities in lasers with injected signal, and many other drastic changes in the behavior of a system.

Objective To evaluate the incidence and risk factors for catheter-related central vein thrombosis in ICU patients. Design Observational prospective multicenter study. Setting An 8-bed surgical ICU, a 10-bed surgical cardiovascular ICU, and a 10-bed medical-surgical ICU. Patients During an 18-month period, 265 internal jugular or subclavian catheters were included. Veins were explored by duplex scanning performed just before or Interventions None. Measurements and main results Fifty-seven catheters were excluded from the analysis. Therefore 208 catheters were analyzed. Mean age of patients was 64±15 years, simplified acute physiologic score was 12±5, organ system failure score at insertion was 1±1, and mean duration of catheterization was 9±5 days. A catheter-related internal jugular or subclavian vein thrombosis occurred in 33% of the cases (42% [95% confidence interval (CI), 34 to 49%] and 10% [95% CI, 3 to 18%], respectively). Thrombosis was limited in 8%, large in 22%, and occlusive in 3% of the cases. Internal jugular route (relative risk [RR], 4.13; 95% CI, 1.72 to 9.95), therapeutic heparinization (RR 0.47; 95% CI, 0.23 to 0.99), and age >64 years (RR, 2.44; 95% CI, 2.05 to 3.19) were independently associated with catheter-related thrombosis. Moreover, the risk of catheter-related sepsis was 2.62-fold higher when thrombosis occurred (p=0.011). Conclusions Catheter-related central vein thrombosis is a frequent complication of central venous catheterization in ICU patients and is closely associated with catheter-related sepsis.

International audience; This work concerns synthesized nickel (hydr)oxide nanoparticles of Ni(OH)2 and Ni1-xCox(OH)2. To characterize these nanopowders and their thermal behavior, we mainly used in-situ high temp. X-ray diffraction. So, we highlight their thermal field of stability, their mineral phase transformation point, the thermodn. size effect and the Cobalt contribution on the nickel (hydr)oxide behavior.

Background : ST segment resolution (RST), during fibrinolysis therapy (FT) for acute myocardial infarction (AMI), is a good marker of myocardial reperfusion. The in-hospital mortality increases with time to reperfusion when cardiogenic shock (CS) complicates AMI. Objectives: The aim of this study is to assess the no-RST during prehospital fibrinolysis for ST segment elevation myocardial infarction (STEMI) complicated by CS as an early predictor of mortality for triage. Method : In a cohort of 643 patients, receiving prehospital FT for STEMI (pain to FT, mean time 120mn), 39 patients had STEMI complicated by CS. ECG was performed prior starting the FT, baseline ECG, and on ICU admission, admission ECG (FT to ICU, mean time 55mn).Two classes of RST were defined : no resolution (RST 30%).ICU mortality was investigated for each class of RST within 30 days. Results : Results are shown in the table below. No-RST on admission ECG is significantly (p