Mathematical Foundations of the Non-Hermitian Skin Effect.

We study the skin effect in a one-dimensional system of finitely many subwavelength resonators with a non-Hermitian imaginary gauge potential. Using Toeplitz matrix theory, we prove the condensation of bulk eigenmodes at one of the edges of the system. By introducing a generalised (complex) Brillouin zone, we can compute spectral bands of the associated infinitely periodic structure and prove that this is the limit of the spectra of the finite structures with arbitrarily large size.

[Angele experiment: innovative care paths for allergy sufferers].

The Angele project (for Allergies complexes: prise en charge globale, diététique et environnementale) is an article 51 experiment in shared care pathways in allergology. These care paths, dedicated to patients with allergies to house dust mites and/or food, involve collaboration between doctors and paramedics. The aim of this initiative is to optimize patient care by structuring their care pathways.

Topological phenomena in honeycomb Floquet metamaterials.

Being driven by the goal of finding edge modes and of explaining the occurrence of edge modes in the case of time-modulated metamaterials in the high-contrast and subwavelength regime, we analyse the topological properties of Floquet normal forms of periodically parameterized time-periodic linear ordinary differential equations . In fact, our main goal being the question whether an analogous principle as the bulk-boundary correspondence of solid-state physics is possible in the case of Floquet metamaterials, i.e.

Anderson Localization in the Subwavelength Regime.

In this paper, we use recent breakthroughs in the study of coupled subwavelength resonator systems to reveal new insight into the mechanisms responsible for the fundamental features of Anderson localization. The occurrence of strong localization in random media has proved difficult to understand, particularly in physically derived multi-dimensional models and systems with long-range interactions. We show here that the scattering of time-harmonic waves by high-contrast resonators with randomly chosen material parameters reproduces the characteristic features of Anderson localization.

Significant decrease of facial cellulitis admissions during COVID-19 lockdown in France: A multicentric comparative study.

During the 2020 coronavirus pandemic, a lockdown was imposed in France during the first wave. An apparent decrease in incidence of cellulitis of odontogenic origin was noticed then. This study aimed to compare the incidence of cellulitis during this extraordinary period with the same period in 2018 and 2019, based on retrospective multicentric data.