Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

lnterférences de type Young avec une source à un seul électron

International audienceDes interférences dues à la diffusion d'un électron unique sur deux protons, qui jouent le rôle de deux trous de Young, ont été mises en évidence expérimentalement pour la première fois. L'électron provient de l'auto-ionisation de l'hélium excité après capture des deux électrons de la molécule H2 par un projectile He2+. Ces interférences se manifestent par l'apparition d'oscillations d'intensité dans la distribution angulaire des électrons diffusés. La présence de ces oscillations prouve qu'un électron peut interférer avec lui-même. L'expérience présente est analogue à une expérience de pensée imaginée par Feynman en 1963

Physique/Physique subatomique. Interférences de type Young avec une source à un seul électron

RESUME : Des interférences dues à la diffusion d'un électron unique sur deux protons, qui jouent le rôle de deux trous d'Young, ont été mises en évidence expérimentalement pour la première fois. L'électron provient de l'autoionisation de l'hélium excité après capture des deux électrons de la molécule H2 par un projectile He2+. Ces interférences se manifestent par l'apparition d'oscillations dans la distribution angulaire des électrons diffusés. La présence de ces oscillations prouve qu'un électron peut interférer avec lui-même. Cette expérience est analogue à l'expérience de pensée imaginée par Feynman en 1963, dans laquelle il retrace le devenir d'un électron après traversée de deux fentes rapprochées. Pour citer cet article : F. Frémont et al., C. R. Physique 9 (2008). ABSTRACT : Young-type interference with a one electron source. In the present work we provide experimental evidence for Young-type interferences caused by one single electron acting on a given double-center scatterer which is analogous to an atomic-size doubleslit apparatus. The interfering electron is provided by autoionization of a doubly-excited helium atom following the capture of the two H2 target electrons by a He2+ incoming projectile ion. In the backward direction, the auto-ionized electron scatters on the two H+ centers of the fully ionized target molecule. Here, the auto-ionizing projectile plays the role of a single-electron source, independent of the interferometer provided by the residual two-center target. The present experiment resembles the famous “thought experiment” imagined by Feynman in 1963, in which the quantum nature of the electron is illustrated from a Younglike double-slit experiment. Similarly to the case of Young's experiment with light, the interference effect manifests itself in well defined oscillations in the angular distribution of the scattered electrons. To cite this article: F. Frémont et al., C. R. Physique 9 (2008)

Methodology of backside preparation applied on a MRAM to lead a logical investigation with a near-field probe

This paper presents a method for the preparation of a magnetic random access memory (MRAM) whose data are stored in magnetic tunnel junctions (MTJ) as resistance states, in order to read them by near-field probing.The goal is to be able to visualize a difference of resistance between bits at ‘0’ and at ‘1’ thanks to the current passing through several MTJs. To do so, the MRAM needs to be prepared to create an electrical access to both sides of the MTJs. The main issue is the polishing of both sides as the stack of metallization being less than 10 μm thick. A chemical etch would in that case be encouraged by literature but we take a different approach since we choose to open further than the transistors. The preferred method is a backside preparation technique that creates a bevel allowing us to access the bottom side of the MTJs through vias and the top of them thanks to the bitlines. Since the resulting chip no longer has electrical connections, we also create a dedicated electrical path thanks to a focused ion beam (FIB) operation. At the end, it is then possible to collect the current flowing through the MTJs with a near-field probe. To probe the MTJ resistance, two near-field techniques are investigated: conductive atomic force microscopy (C-AFM) and scanning spreading resistance microscopy (SSRM). C-AFM provides a quite high resistivity probably due to its sensitivity to contact resistance. Using SSRM, a resistance of 12–16 kΩ and 17–22 kΩ were determined for “0” and “1” bits, which is in agreement with literature

Mise en place d'une pédagogie d'apprentissage par problèmes au département GEII de l'IUT Bordeaux

International audienc

Linewidth oscillations in a nanometer-size double-slit interference experiment with single electrons

International audienceIn this article we provide experimental evidence of an interference phenomenon that, to the best of our knowledge, has so far not been observed with either matter or light. In a nanometer-sized version of Feynman's famous two-slit “thought” experiment with single electrons, we managed to observe that the width of a quasimonochromatic line oscillates with the detection angle. Furthermore, we find that it occurs in counterphase with the line intensity. We discuss the underlying mechanism that produces this unexpected result