Sound Source Separation

This is the author's accepted pre-print of the article, first published as G. Evangelista, S. Marchand, M. D. Plumbley and E. Vincent. Sound source separation. In U. Zölzer (ed.), DAFX: Digital Audio Effects, 2nd edition, Chapter 14, pp. 551-588. John Wiley & Sons, March 2011. ISBN 9781119991298. DOI: 10.1002/9781119991298.ch14file: Proof:e\EvangelistaMarchandPlumbleyV11-sound.pdf:PDF owner: markp timestamp: 2011.04.26file: Proof:e\EvangelistaMarchandPlumbleyV11-sound.pdf:PDF owner: markp timestamp: 2011.04.2

Bio-Inspired Hovering Control for an Aerial Robot Equipped with a Decoupled Eye and a Rate Gyro

International audienceThis work provides an hovering control strategy for a sighted robot, the eye of which being decoupled from the body and controlled by means of a tiny rotative piezo motor. The main purpose of this paper is to show the effectiveness and the efficiency of this fundamental bio-inspired mechanical decoupling. Indeed, it exhibits several benefits: * it enables to stabilize the robot's gaze on the basis of three bio-inspired oculomotor reflexes (ORs) : a visual fixation reflex (VFR), a translational and rotational vestibulo- ocular reflexes (tVOR and rVOR), * the eye can better, quickly and accurately compensate for sudden, untoward disturbances caused by the vagaries of the supporting head or body, * it yields a reference visual signal that can be used to unbias the rate gyro used to implement the VORs and to stabilize the hovering robot, * it increases the tracking accuracy with moving targets compared to without OR, This paper shows also that lateral disturbances are rejected 2 times faster with the decoupled eye robot, and roll perturbations induce a retinal error 20 times smaller. The occulomotor reflexes enables to cancel retinal error 6 times faster with 5 times lower retinal error picks. The conclusion of the paper is that decoupled eye must be considered as an efficient autonomous flight solution

Intracerebral Implantation of Ionic Synthetic Hydrogels: Effect of Polar Substrata on Astrocytosis and Axons

In previous studies, hyperporous synthetic hydrogels of poly(glyceryl methacrylate) or p(GMA), containing bioadhesive substrates of collagen, were implanted into rat cerebral tissue in order to provide systems of oriented guidance channels for directing the growth of the scar and axons /28/. In the present study, ionic p(GMA)- collagen hydrogels containing polar chemical groups, either basic amino groups or acidic carboxyl groups, were evaluated for their tolerance and their effects on the brain scarring response and axonal reactivity after long-term implantation in the cerebral cortex. In all animals, the implants were well tolerated. Although both types of gels influenced the astroglial reaction near the bioimplant, hydrogels carrying carboxyl groups had the strongest influence on the elongation, the direction and the organization of astrocytic processes so that a glial matrix could form in regions of the gel. Extracellular material (e.g. reticulin) was also deposited into the gels carrying carboxyl groups. Although cortical nerve fibers .in the surrounding tissue showed a regenerative response, extending onto or into the matrices, this behavior seemed to depend more on the organization of the .astrocytic scar imposed by the gel than on the type of gel. We conclude that matrices carrying negatively charged groups influence favorably the astrocytosis and the deposition of connective tissue, and that this approach represents a new avenue in attempting to modulate the brain scar formation

Time-trends and treatment gaps in the antithrombotic management of patients with atrial fibrillation after percutaneous coronary intervention: Insights from the CHUM AF-STENT Registry.

BACKGROUND: The management of atrial fibrillation and flutter (AF) patients undergoing percutaneous coronary intervention (PCI) has undergone a rapid recent evolution. In 2016, the Canadian Cardiovascular Society (CCS) published expert recommendations to help guide clinicians in balancing bleeding and thrombotic risks in these patients. HYPOTHESIS: Antithrombotic regimen prescriptions for AF patients undergoing PCI evolved after the publication of the 2016 CCS AF guidelines. METHODS: A prospective cohort of AF patients undergoing PCI with placement of a coronary stent from a single tertiary academic center was analyzed for the recommended antithrombotic regimen at discharge. Prescribing behavior was compared between three time periods (Cohort A [2010-2011]; Cohort B [2014-2015]; Cohort C [2017]) using the χ2 test. In addition, antithrombotic management in Cohorts B and C were compared to guideline-recommended therapy. RESULTS: A total of 459 patients with AF undergoing PCI were identified. Clinical and procedural characteristics were similar between cohorts, with the exception of an increase in drug-eluting stent (DES) use over time (P < .01). Overall, the rate of oral anticoagulation (OAC) increased over time (P < .01), associated with an increase in nonvitamin K OAC prescription (P < .01) and a concomitant decrease in vitamin K antagonist prescription (P < .01). Despite this, the overall rate of anticoagulation remains below what would be predicted with perfect guideline compliance (75% vs 94%, P < .01). CONCLUSION: There has been a dramatic shift in clinical practice for AF patients requiring PCI, with increases in prescription of OAC even in the context of an increase in the use of DES. However, room for further practice optimization still exists

Origin of line tension for a Lennard-Jones nanodroplet

The existence and origin of line tension has remained controversial in literature. To address this issue we compute the shape of Lennard-Jones nanodrops using molecular dynamics and compare them to density functional theory in the approximation of the sharp kink interface. We show that the deviation from Young's law is very small and would correspond to a typical line tension length scale (defined as line tension divided by surface tension) similar to the molecular size and decreasing with Young's angle. We propose an alternative interpretation based on the geometry of the interface at the molecular scale

Coarctation of the Aorta in Infants Under One Year of Age

During the 10-year period 1962 - 1971, coarctation of the aorta was diagnosed within the first 5 months of life in 35 hospital cases. Of these, 29 (83%) were symptomatic, and 18 (54%) underwent surgery to correct the coarctation. Thirteen of the 18 patients (72%) survived the procedure. Of the 5 patients who died, 2 had single-ventricle complexes, and 1 had an associated ventricular septal defect and died at a subsequent operation for pulmonary artery banding. One patient who survived had a thoracotomy with no procedure done to the aorta. All survivors were followed up for at least 1 year. Residual gradients were found in 6 of the 12 patients (50%), but classified as severe in only 2 cases. Of the 11 patients who were symptomatic but who did not undergo surgery, 7 died (mortality 63%). There were 6 remaining patients who were asymptomatic. There have been 3 deaths in this series-all unrelated to their cardiac pathology. It is strongly recommended that young babies with coarctation of the aorta, who develop congestive cardiac failure, undergo 36 - 48 hours of medical therapy, after which surgical resection of the coiucted segment is carried out. This approach offers the best prospects for survival.S. Afr. Med. J., 48, 397 (1974

Sharp transition for single polarons in the one-dimensional Su-Schrieffer-Heeger model

We study a single polaron in the Su-Schrieffer-Heeger (SSH) model using four different techniques (three numerical and one analytical). Polarons show a smooth crossover from weak to strong coupling, as a function of the electron-phonon coupling strength $\lambda$, in all models where this coupling depends only on phonon momentum $q$. In the SSH model the coupling also depends on the electron momentum $k$; we find it has a sharp transition, at a critical coupling strength $\lambda_c$, between states with zero and nonzero momentum of the ground state. All other properties of the polaron are also singular at $\lambda = \lambda_c$, except the average number of phonons in the polaronic cloud. This result is representative of all polarons with coupling depending on $k$ and $q$, and will have important experimental consequences (eg., in ARPES and conductivity experiments)

Coarctation of the aorta in infants under one year of age

During the 10-year period 1962 - 1971, coarctation of the aorta was diagnosed within the first 5 months of life in 35 hospital cases. Of these, 29 (83%) were symptomatic, and 18 (54%) underwent surgery to correct the coarctation. Thirteen of the 18 patients (72%) survived the procedure. Of the 5 patients who died, 2 had single-ventricle complexes, and 1 had an associated ventricular septal defect and died at a subsequent operation for pulmonary artery banding. One patient who survived had a thoracotomy with no procedure done to the aorta.All survivors were followed up for at least 1 year. Residual gradients were found in 6 of the 12 patients (50%), but classified as severe in only 2 cases.Of the 11 patients who were symptomatic but who did not undergo surgery, 7 died (mortality 63%). There were 6 remaining patients who were asymptomatic. There have been 3 deaths in this series-all unrelated to their cardiac pathology.It is strongly recommended that young babies with coarctation of the aorta, who develop congestive cardiac failure, undergo 36 - 48 hours of medical therapy, after which surgical resection of the coiucted segment is carried out. This approach offers the best prospects for survival.S. Afr. Med. J, 48, 397 (1974)