Parabolic Anderson model with voter catalysts: dichotomy in the behavior of Lyapunov exponents

We consider the parabolic Anderson model $\partial u/\partial t = \kappa\Delta u + \gamma\xi u$ with $u\colon\, \Z^d\times R^+\to \R^+$, where $\kappa\in\R^+$ is the diffusion constant, $\Delta$ is the discrete Laplacian, $\gamma\in\R^+$ is the coupling constant, and $\xi\colon\,\Z^d\times \R^+\to\{0,1\}$ is the voter model starting from Bernoulli product measure $\nu_{\rho}$ with density $\rho\in (0,1)$. The solution of this equation describes the evolution of a "reactant" $u$ under the influence of a "catalyst" $\xi$. In G\"artner, den Hollander and Maillard 2010 the behavior of the \emph{annealed} Lyapunov exponents, i.e., the exponential growth rates of the successive moments of $u$ w.r.t.\ $\xi$, was investigated. It was shown that these exponents exhibit an interesting dependence on the dimension and on the diffusion constant. In the present paper we address some questions left open in G\"artner, den Hollander and Maillard 2010 by considering specifically when the Lyapunov exponents are the a priori maximal value in terms of strong transience of the Markov process underlying the voter model.Comment: In honour of J\"urgen G\"artner on the occasion of his 60th birthday, 33 pages. Updated version following the referee's comment

A comment on free-fermion conditions for lattice models in two and more dimensions

We analyze free-fermion conditions on vertex models. We show --by examining examples of vertex models on square, triangular, and cubic lattices-- how they amount to degeneration conditions for known symmetries of the Boltzmann weights, and propose a general scheme for such a process in two and more dimensions.Comment: 12 pages, plain Late

Les algorithmes de recommandation musicale et l’autonomie de l’auditeur. Analyse des écoutes d'un panel d'utilisateurs de streaming

International audienceStreaming music listening services are halfway between two previously existing devices – radio and record collections –, and two related types of agency – the consumer supported by music programming in the case of radio, and the amateur in the case of collection. They therefore offer a hybrid system of personalized services, adapted to users’ tastes, based on their past listening, through the use of recommendation systems. To what extent is the figure drawn by the interfaces reflected in the listeners’ real behaviour? To answer this question, we draw on the analysis of logs of musical activity from a random sample of 4,000 users of a musical platform, monitored over a period of five months. We first describe the distribution of listening, and show that while the diversity of consumption on the platform is greater than on other devices, listening remains highly concentrated on the most popular musicians. We then examine the use of recommendations, showing that it remains moderate and unevenly distributed, and that for musical discovery, it is still marginal, whether the orientation of the recommendations is towards mid-tail and long-tail music.Les services d’écoute musicale en streaming se situent à mi-chemin entre deux dispositifs antérieurs, la radio et la collection de disques, et deux modes d’agentivité associés : le consommateur pris en charge par la programmation musicale dans le cas de la radio, l’amateur dans le cas de la collection. Ils proposent ainsi un régime hybride de prise en charge personnalisée, adaptée aux goûts des usagers, mesurés par leurs écoutes passées, via l’usage de systèmes de recommandation. Dans quelle mesure la figure dessinée par les interfaces se traduit-elle dans les comportements réels des auditeurs ? Nous nous appuyons sur l’analyse des traces d’activités musicales d’un échantillon aléatoire de 4000 utilisateurs d’une plateforme musicale, suivi pendant une période de cinq mois, pour répondre à cette question. Nous décrivons d’abord la distribution des écoutes, et montrons que si la diversité des consommations sur la plateforme est plus grande que sur d’autres dispositifs, les écoutes demeurent fortement concentrées sur les artistes les plus populaires. Nous examinons ensuite les usages des recommandations par les usagers, en montrant qu’ils restent mesurés, inégalement distribués, et que les usages de découverte musicale, s’ils orientent les usagers vers des musiques de la mid-tail et de la long-tail, demeurent marginaux

Caractérisation des dommages au choc de composites stratifiés aéronautiques : application à la chute d'objets

International audienceCette étude porte sur la caractérisation des dommages de plaques stratifiées carbone/époxy suite à un impact basse vitesse. Les stratifiés étudiés sont constitués de nappes pré-imprégnées unidirectionnelles superposées de M21/T700GC. Les essais ont été réalisés en faisant varier masse de l'impacteur et hauteur de chute en conservant pour chaque essai, un niveau d'énergie identique recommandée par la norme aéronautique. L'instrumentation de l'essai ainsi que l'analyse multi physique réalisée sur les plaques impactées ont permis de mieux comprendre les mécanismes d'endommagements du matériau stratifié testé. En effet, ont été couplés accéléromètre, caméra rapide et jauges de déformations pour les mesures pendant l'essai. Une étude thermographique et une analyse aux ultrasons des plaques impactées ont révélés la localisation des endommagements dans les différents stratifiés testés. A niveau d'énergie initiale constante, les plaques testées avec la masse la plus importante sont très largement endommagées par rapport aux plaques impactées avec une faible masse

Correction: The psychiatric phenotypes of 1q21 distal deletion and duplication.

Copy number variants are amongst the most highly penetrant risk factors for psychopathology and neurodevelopmental deficits, but little information about the detailed clinical phenotype associated with particular variants is available. We present the largest study of the microdeletion and -duplication at the distal 1q21 locus, which has been associated with schizophrenia and intellectual disability, in order to investigate the range of psychiatric phenotypes. Clinical and cognitive data from 68 deletion and 55 duplication carriers were analysed with logistic regression analysis to compare frequencies of mental disorders between carrier groups and controls, and linear mixed models to compare quantitative phenotypes. Both children and adults with copy number variants at 1q21 had high frequencies of psychopathology. In the children, neurodevelopmental disorders were most prominent (56% for deletion, 68% for duplication carriers). Adults had increased prevalence of mood (35% for deletion [OR = 6.6 (95% CI: 1.4–40.1)], 55% for duplication carriers [8.3 (1.4–55.5)]) and anxiety disorders (24% [1.8 (0.4–8.4)] and 55% [10.0 (1.9–71.2)]). The adult group, which included mainly genetically affected parents of probands, had an IQ in the normal range. These results confirm high prevalence of neurodevelopmental disorders associated with CNVs at 1q21 but also reveal high prevalence of mood and anxiety disorders in a high-functioning adult group with these CNVs. Because carriers of neurodevelopmental CNVs who show relevant psychopathology but no major cognitive impairment are not currently routinely receiving clinical genetic services widening of genetic testing in psychiatry may be considered

Psychiatric disorders in children with 16p11.2 deletion and duplication

Deletion and duplication of 16p11.2 (BP4–BP5) have been associated with an increased risk of intellectual disability and psychiatric disorder. This is the first study to compare the frequency of a broad spectrum of psychiatric disorders in children with 16p11.2 deletion and duplication. We aimed to evaluate (1) the nature and prevalence of psychopathology associated with copy number variation (CNV) in children with 16p11.2 by comparing deletion and duplication carriers with family controls; (2) whether deletion and duplication carriers differ in frequency of psychopathology. 217 deletion carriers, 77 deletion family controls, 114 duplication carriers, and 32 duplication family controls participated in the study. Measures included standardized research diagnostic instruments. Deletion carriers had a higher frequency of any psychiatric disorder (OR = 8.9, p < 0.001), attention deficit hyperactivity disorder (ADHD) (OR = 4.0, p = 0.01), and autism spectrum disorder (ASD) (OR = 39.9, p = 0.01) than controls. Duplication carriers had a higher frequency of any psychiatric diagnosis (OR = 5.3, p = 0.01) and ADHD (OR = 7.0, p = 0.02) than controls. The prevalence of ASD in child carriers of deletions and duplications was similar (22% versus 26%). Comparison of the two CNV groups indicated a higher frequency of ADHD in children with the duplication than deletion (OR = 2.7, p = 0.04) as well as a higher frequency of overall psychiatric disorders (OR = 2.8, p = 0.02) and psychotic symptoms (OR = 4.7, p = 0.02). However, no differences between deletion and duplications carriers in the prevalence of ASD were found. Both deletion and duplication are associated with an increased risk of psychiatric disorder, supporting the importance of early recognition, diagnosis, and intervention in these groups

2-Year Outcomes of High Bleeding Risk Patients After Polymer-Free Drug-Coated Stents.

BACKGROUND: A 1-year follow-up, polymer-free metallic stent coated with biolimus-A9 followed by 1-month dual antiplatelet therapy is safer and more effective than a bare-metal stent (BMS) for patients with high risk of bleeding. OBJECTIVES: This study analyzed 2-year outcomes to determine whether these benefits are maintained. METHODS: In a prospective, multicenter, double-blind trial, we randomized 2,466 high bleeding risk patients to receive a drug-coated stent (DCS) or a BMS followed by 1-month dual antiplatelet therapy. The primary safety endpoint was a composite of cardiac death, myocardial infarction, or stent thrombosis. The primary efficacy endpoint was clinically driven target lesion revascularization. RESULTS: At 2 years, the primary safety endpoint had occurred in 147 DCS and 180 BMS patients (15.3%) (hazard ratio: 0.80; 95% confidence interval: 0.64 to 0.99; p = 0.039). Clinically driven target lesion revascularization occurred for 77 DCS and 136 BMS patients (12.0%) (hazard ratio: 0.54; 95% confidence interval: 0.41 to 0.72; p 75 years, anemia, raised plasma creatinine, and planned long-term anticoagulation. Correlates of the primary safety endpoint were age, anemia, congestive heart failure, multivessel disease, number of stents implanted, and use of a BMS rather than a DCS. CONCLUSIONS: Safety and efficacy benefits of DCS over BMS were maintained for 2 years in high bleeding risk patients. Rates of major bleeding and coronary thrombotic events were no different and were associated with a substantial and comparable mortality risk. (A Prospective Randomized Comparison of the BioFreedom Biolimus A9 Drug Coated Stent Versus the Gazelle Bare Metal Stent in Patients With High Risk of Bleeding [LEADERS FREE]; NCT01623180)

Pan-European landscape of research into neurodevelopmental copy number variants: a survey by the MINDDS consortium

Background Several rare copy number variants have been identified to confer risk for neurodevelopmental disorders (NDD-CNVs), and increasingly NDD-CNVs are being identified in patients. There is a clinical need to understand the phenotypes of NDD-CNVs. However due to rarity of NDD-CNVs in the population, within individual countries there is a limited number of NDD-CNV carriers who can participate in research. The pan-european MINDDS (Maximizing Impact of Research in Neurodevelopmental Disorders) consortium was established in part to address this issue. Methodology A survey was developed to scope out the current landscape of NDD-CNV research across member countries of the MINDDS consortium, and to identify clinical cohorts with potential for future research. Results 36 centres from across 16 countries completed the survey. We provide a list of centres who can be contacted for future collaborations. 3844 NDD-CNV carriers were identified across clinical and research centres spanning a range of medical specialties, including psychiatry, paediatrics, medical genetics. A broad range of phenotypic data was available; including medical history, developmental history, family history and anthropometric data. In 12/16 countries, over 75% of NDD-CNV carriers could be recontacted for future studies. Conclusion This survey has highlighted the potential within Europe for large multi-centre studies of NDD-CNV carriers, to improve knowledge of the complex relationship between NDD-CNV and clinical phenotype. The MINNDS consortium is in a position to facilitate collaboration, data-sharing and knowledge exchange on NDD-CNV phenotypes across Europe

The Fire Within: Microbes Inflame Tumors

The immune system and the microbiota mutually interact to maintain homeostasis in the intestine. However, components of the microbiota can alter this balance and promote chronic inflammation, promoting intestinal tumor development. We review recent advances in understanding the complex interactions between the microbiota and the innate and adaptive immune systems and discuss their potential to lead us in new directions for understanding cancer biology and treatment

High-level IGF1R expression is required for leukemia-initiating cell activity in T-ALL and is supported by Notch signaling

Notch-driven expression of IGF1R promotes the growth, viability, and transplantability of T-ALL cells