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A 25-month-old child presented with unilateral hearing loss; examination found unilateral right middle ear effusion of cerebrospinal fluid. What is your diagnosis?

To evaluate objective vestibular function after endolymphatic sac surgery (ELSS) for Menière's disease (MD), using comparative vestibular function tests: videonystagmography (VNG), vestibular evoked myogenic potentials (VEMP) and video head-impulse test (VHIT) METHODS: Patients with definite MD using the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) of 1995 criteria modified in 2015 and treated with ELSS (sac decompression or sac opening) were included. The primary outcome was the preservation of vestibular function, comparing pre- and postoperative vestibular function tests: VNG, VEMP, VHIT. Secondary outcomes were control of episodes of vertigo, hearing outcome using AAO-HNS criteria, and QoL using the Menière's disease outcome questionnaire.73 patients were included in the study. We found a significant preservation of vestibular function as measured by VNG and VHIT. There was no statistical difference in the presence or absence of cervical and ocular (P13/N23 and N1/P1) waves on VEMP pre- and postoperatively. 67% of patients had good control of episodes of vertigo post-operatively, with significantly better results in the sac opening group (75%). There was no significant change in hearing postoperatively, and QoL scores were significantly improved after surgery (p 0.0001).Endolymphatic sac surgery (ELSS) is a conservative surgical treatment, which does not negatively impact vestibular function. It was associated with improved control of episodes of vertigo, preservation of hearing, and a clear improvement in QoL scores. Despite its pathophysiology not being fully understood, it remains a first-line procedure preserving vestibular function, for MD refractory to medical management.

International audience; Peregrine soliton (PS) is widely regarded as a prototype nonlinear structure capturing properties of rogue waves that emerge in the nonlinear propagation of unidirectional wave trains. As an exact breather solution of the one-dimensional focusing nonlinear Schrödinger equation with nonzero boundary conditions, the PS can be viewed as a soliton on finite background, i.e., nonlinear superposition of a soliton and a monochromatic wave. A recent mathematical work showed that both nonzero boundary conditions and solitonic content are not pre-requisites for the PS occurrence. Instead, it has been demonstrated that PS can emerge locally, as an asymptotic structure arising from the propagation of an arbitrary large decaying pulse, independently of its solitonic content. This mathematical discovery has changed the widely accepted paradigm of the solitonic nature of rogue waves by enabling the PS to emerge from a partially radiative or even completely solitonless initial data. In this work, we realize the mathematically predicted universal mechanism of the local PS emergence in a water tank experiment with a particular aim to control the point of the PS occurrence in space-time by imposing an appropriately chosen initial chirp. By employing the inverse scattering transform for the synthesis of the initial data, we are able to engineer a localized wave packet with a prescribed solitonic and radiative content. This enabled us to control the position of the emergence of the rogue wave by adjusting the inverse scattering spectrum. The proposed method of the nonlinear spectral engineering is found to be robust to higher-order nonlinear effects inevitable in realistic wave propagation conditions.

To understand the advance and retreat of the British and Irish Ice Sheet (BIIS), geomorphic features have been extensively characterised onshore. The extent of these features in the Irish Sea has been poorly constrained, even though the Irish Sea Ice Stream (ISIS) was the largest drainage system of the BIIS and had a strong impact in shaping the present-day seafloor. Previous studies have highlighted the occurrence of till surfaces, glacio-marine and transitional stratigraphic units to marine environments. Constraining the extension of these units and characterising the associated geomorphic features is important to any attempt to reconstruct the history of the BIIS evolution since the Last Glacial Maximum.This study presents new information produced by interrogating large geophysical datasets of sub-bottom profiler, single-channel Sparker, and multibeam echosounder bathymetry in the North-Western Irish Sea, from Dundalk Bay to Lambay Deep. These data spatially map the complex sub-surface stratigraphy, comprising different glacial and post-glacial units and the geomorphic features they form, including grounding-zone wedges, channels, and iceberg scouring. Initial interpretation of these features has been performed with regard to established stratigraphic frameworks and regional glacial and postglacial geodynamic models. This presentation will focus on the results of the geomorphic feature interpretation, with the aim of constraining the ISIS advance and retreat in the North-western Irish Sea, filling a critical gap in our understanding of the demise of the BIIS.

We investigate the statistics of rogue waves occurring in the inverse cascade of surface gravity wave turbulence. In such statistically homogeneous, stationary and isotropic wave fields, low-frequency waves are generated by nonlinear interactions rather than directly forced by a wave maker. This provides a laboratory realization of arguably the simplest nonlinear sea state, in which long-time acquisitions are performed and compared with theoretical models. The analysis of thousands of rogue waves reveals that some of their properties crucially depend on four-wave resonant interactions, large crests being for instance more likely than predicted by second-order models.

International audience; In the absence of natural convection, efficient heat transfers rely on externally forced flows. Generating such flows with acoustic waves rather than mechanical fans would enable remote locations to be cooled using virtually infinite lifetime transducers. This outlook is reinforced by the recent discovery that standing acoustic waves drive streaming flows of much higher velocities if the background medium is inhomogeneous. This regime of streaming is investigated experimentally in a cavity filled with stably-stratified air in which horizontal sound waves are found to significantly enhance heat transfers. The additional heat flux scales as the square of the input acoustic power for low amplitude waves and increases with the air stratification. These two features qualitatively match theoretical predictions, although corrections possibly ascribed to gravity are observed.

A multiscale reduced description of turbulent free shear flows in the presence of strong stabilizing density stratification is derived via asymptotic analysis of the Boussinesq equations in the simultaneous limits of small Froude and large Reynolds numbers. The analysis explicitly recognizes the occurrence of dynamics on disparate spatiotemporal scales, yielding simplified partial differential equations governing the coupled evolution of slow large-scale hydrostatic flows and fast small-scale isotropic instabilities and internal waves. The dynamics captured by the coupled reduced equations is illustrated in the context of two-dimensional strongly stratified Kolmogorov flow. A noteworthy feature of the reduced model is that the fluctuations are constrained to satisfy quasilinear (QL) dynamics about the comparably slowly varying large-scale fields. Crucially, this QL reduction is not invoked as an ad hoc closure approximation, but rather is derived in a physically relevant and mathematically consistent distinguished limit. Further analysis of the resulting slow–fast QL system shows how the amplitude of the fast stratified-shear instabilities is slaved to the slowly evolving mean fields to ensure the marginal stability of the latter. Physically, this marginal stability condition appears to be compatible with recent evidence of self-organized criticality in both observations and simulations of stratified turbulence. Algorithmically, the slaving of the fluctuation fields enables numerical simulations to be time-evolved strictly on the slow time scale of the hydrostatic flow. The reduced equations thus provide a solid mathematical foundation for future studies of three-dimensional strongly stratified turbulence in extreme parameter regimes of geophysical relevance and suggest avenues for new sub-grid-scale parametrizations.

In otolaryngologic surgery, endoscopy is increasingly used to provide a better view of hard-to-reach areas and to promote minimally invasive surgery. However, the need to manipulate the endoscope limits the surgeon's ability to operate with only one instrument at a time. Currently, several robotic systems are being developed, demonstrating the value of robotic assistance in microsurgery. The aim of this literature review is to present and classify current robotic systems that are used for otological and endonasal applications. For these solutions, an analysis of the functionalities in relation to the surgeon's needs will be carried out in order to produce a set of specifications for the creation of new robots., Comment: Journal of Medical Devices, American Society of Mechanical Engineers (ASME), 2021

Pruning seeks to design lightweight architectures by removing redundant weights in overparameterized networks. Most of the existing techniques first remove structured sub-networks (filters, channels,...) and then fine-tune the resulting networks to maintain a high accuracy. However, removing a whole structure is a strong topological prior and recovering the accuracy, with fine-tuning, is highly cumbersome. In this paper, we introduce an "end-to-end" lightweight network design that achieves training and pruning simultaneously without fine-tuning. The design principle of our method relies on reparametrization that learns not only the weights but also the topological structure of the lightweight sub-network. This reparametrization acts as a prior (or regularizer) that defines pruning masks implicitly from the weights of the underlying network, without increasing the number of training parameters. Sparsity is induced with a budget loss that provides an accurate pruning. Extensive experiments conducted on the CIFAR10 and the TinyImageNet datasets, using standard architectures (namely Conv4, VGG19 and ResNet18), show compelling results without fine-tuning., Accepted at International Conference on Image Processing (ICIP 2021)

Anticipating the possibility of olfactory recovery after functional endoscopic surgery (FES) in nasal polyposis (NP) is difficult. The main objective of this study was to assess the predictive factors of recovering the sense of smell after radical bilateral ethmoidectomy. Secondary objectives were to identify other predictors of olfactory recovery. Open prospective study was conducted at the Nantes University Hospital including all patients with NP operated on in the Ear, Nose, and Throat Department between January 2011 and September 2017. These patients underwent functional endoscopic surgery (radical ethmoidectomy) after medical treatment failure. Olfaction was quantified prospectively and systematically during the preoperative consultation using a visual analog scale. Multivariate analysis evaluated the presence of predictive factors of postoperative olfactory recovery. One hundred nineteen patients were included in the study. Overall, olfaction was partially improved after surgery. For patients who presented greater than 50% recovery of olfaction after systemic corticosteroid therapy before surgery, we observed a predictive better rate of olfactory recovery after surgery (p

Fabry disease (FD) is a lysosomal storage disease responsible for cochleovestibular involvement. Exact prevalence and pathophysiological mechanisms behind ENT affections are still poorly known. Treating FD with enzyme replacement therapy (ERT) does not seem to significantly improve the ENT symptoms, while the impact of migalastat has yet to be determined. We carried out a retrospective multi-centre study on 47 patients from the FFABRY cohort who had an ENT consultation in the context of their FD. The information collected were as follows: clinical examination, videonystagmoscopy, pure-tone speech audiometry, videonystagmography or VHIT (Video Head Impulse Test). Severe hearing loss was defined as greater than 70 dB. The median age of our cohort was 52 years with a non-negligible proportion of non-classic variants and female carriers. 72.3% of the patients complained of at least one of the following symptoms: hearing loss, tinnitus or vertigo. Pure-tone audiometry was abnormal in 61.7% of the patients (29/47), while speech audiometry was abnormal for 41.7% of the patients. The age of the patients and hypertrophic cardiomyopathy were significantly associated with the existence of an anomaly in pure-tone audiometry results. Severe hearing loss (> 70 dB) was significantly more common in male patients. Hearing loss is particularly frequent in FD and is not limited to classic phenotypes. Close ENT follow-up is essential for Fabry patients to detect those who might benefit from hearing aid. Further studies are needed to define the impact of migalastat on cochleovestibular symptoms.

International audience; Soliton gases represent large random soliton ensembles in physical systems that display integrable dynamics at the leading order. Despite significant theoretical developments and observational evidence of ubiquity of soliton gases in fluids and optical media their controlled experimental realization has been missing. We report the first controlled synthesis of a dense soliton gas in deep-water surface gravity waves using the tools of nonlinear spectral theory (inverse scattering transform (IST)) for the one-dimensional focusing nonlinear Schrödinger equation. The soliton gas is experimentally generated in a one-dimensional water tank where we demonstrate that we can control and measure the density of states, i. e. the probability density function parametrizing the soliton gas in the IST spectral phase space. Nonlinear spectral analysis of the generated hydrodynamic soliton gas reveals that the density of states slowly changes under the influence of perturbative higher-order effects that break the integrability of the wave dynamics.

European Conference on Mechanism Science (EUCOMES'2022), Sep 2022, Cluj-Napoca, Romania; International audience; This paper deals with the joint space and workspace analysis of a two degree of freedom spherical parallel mechanism designed to be used to handle an endoscope. This mechanism is composed of the three legs (2USP-U) to connect the base to a moving platform. As the manipulator can get up to six solutions to the direct kinematic problem (DKP) in four aspects, non-singular assembly modes changing trajectories may exist. The aim of the paper is to check whether a regular workspace centred on home pose can be defined in such a way that no such trajectory exists in this workspace.

Estuarine benthic habitat quality health is integrated within the framework of the EU Water Directive and Marine Strategy Framework Directive. The long-term monitoring of small and medium-scale estuarine benthic habitat is based on recurrent observation of several factors, mainly bathymetry and seabed nature. Numerous studies have already addressed the performance and limitations of acoustic remote sensing and mapping techniques. However, most of these studies are limited to the marine and coastal domains and do not include the estuarine domain. Estuaries are considered as transitional domains, with various seabed morphologies (from rocky reefs to hydraulic dunes with anthropic modification overlap) and subtle granulometric variations of the seabed nature.The objectives of our study are to explore the mapping performance of several acoustic remote sensing techniques and to determine which physical factors are the most representative of morphological and sedimentological characteristics of subtidal estuarine environment and of its evolution. The exploration of these cartographic variables has been performed for three small and medium-scale French estuaries: the Orne estuary, the Baie de Somme and the Belon estuary. These estuaries have been chosen to cover different morphological and sedimentological estuarine contexts.Firstly, we evaluate the capacity of the main variables derived from bathymetry (slope, curvature, ruggedness) to map seabed morphology. We extend the variable exploration to the “Terrain Variable” GIS category and BTM (Benthic Terrain Modeler Toolbox) as well. Secondly, we explore the capacity of several cartographic variables, extracted from bathymetric, seabed acoustic backscatter and acoustic ground discrimination system (i.e. RoxAnn©), to map seabed sediment characteristics and variations. The seabed nature mapping is validated with ground truthing data, namely grab samples and seabed video profiles. Moreover, quantitative (D90, roughness, sorting) and qualitive information (apparent roughness of the seabed, benthic habitat) are extracted from the grab samples and seabed video profiles, respectively. The capacity of these variables to produce seabed nature maps is also explored.Mapping results on the three areas are compared, in terms of mapping precision and reproducibility, and transposed into recommendations for small and medium-scale estuaries monitoring. The next step of the AUPASED project is he exploration of image analysis and machine learning classifications and their comparison to manual morphological and sedimentological maps produced.The AUPASED project is funded by the AFB (French Agency for Biodiversity) as part of a convention between the AFB and the CNRS (UMR 6143, M2C).

Determinantal point processes (DPPs) generate random configuration of points where the points tend to repel each other. The notion of repulsion is encoded by the sub-determinants of a kernel matrix, in the sense of kernel methods in machine learning. This special algebraic form makes DPPs attractive both in statistical and computational terms. This thesis focuses on sampling from such processes, that is on developing simulation methods for DPPs. Applications include numerical integration, recommender systems or the summarization of a large corpus of data. In the finite setting, we establish the correspondence between sampling from a specific type of DPPs, called projection DPPs, and solving a randomized linear program. In this light, we devise an efficient Markov-chain-based sampling method. In the continuous case, some classical DPPs can be sampled by computing the eigenvalues of carefully randomized tridiagonal matrices. We provide an elementary and unifying treatment of such models, from which we derive an approximate sampling method for more general models. In higher dimension, we consider a special class of DPPs used for numerical integration. We implement a tailored version of a known exact sampler, which allows us to compare the properties of Monte Carlo estimators in new regimes. In the context of reproducible research, we develop an open-source Python toolbox, named DPPy, which implements the state of the art sampling methods for DPPs; Un processus ponctuel déterminantal (DPP) génère des configurations aléatoires de points ayant tendance à se repousser. La notion de répulsion est encodée par les sous-déterminants d’une matrice à noyau, au sens des méthodes à noyau en apprentissage artificiel. Cette forme algébrique particulière confère aux DPP de nombreux avantages statistiques et computationnels. Cette thèse porte sur l'échantillonnage des DPP, c'est à dire sur la conception d'algorithmes de simulation pour ce type de processus. Les motivations pratiques sont l'intégration numérique, les systèmes de recommandation ou encore la génération de résumés de grands corpus de données. Dans le cadre fini, nous établissons la correspondance entre la simulation de DPP spécifiques, dits de projection, et la résolution d'un problème d'optimisation linéaire dont les contraintes sont randomisées. Nous en tirons une méthode efficace d'échantillonnage par chaîne de Markov. Dans le cadre continu, certains DPP classiques peuvent être simulés par le calcul des valeurs propres de matrices tridiagonales aléatoires bien choisies. Nous en fournissons une nouvelle preuve élémentaire et unificatrice, dont nous tirons également un échantillonneur approché pour des modèles plus généraux. En dimension supérieure, nous nous concentrons sur une classe de DPP utilisée en intégration numérique. Nous proposons une implémentation efficace d'un schéma d'échantillonnage exact connu, qui nous permet de comparer les propriétés d'estimateurs Monte Carlo dans de nouveaux régimes. En vue d'une recherche reproductible, nous développons une boîte à outils open-source, nommée DPPy, regroupant les différents outils d'échantillonnage sur les DPP.

International audience; Since the insertion area in the middle ear or in the sinus cavity is very narrow, the mobility of the endoscope is reduced to a rotation around a virtual point and a translation for the insertion of the camera. This article first presents the anatomy of these regions obtained from 3D scanning and then a mechanism based on the architecture of the agile eye coupled to a double parallelogram to create an RCM. This mechanism coupled with a positioning mechanism is used to handle an endoscope. This tool is used in parallel to the surgeon to allow him to have better rendering of the medium ear than the use of Binocular scope. The mechanism offers a wide working space without singularity whose borders are fixed by joint limits. This feature allows ergonomic positioning of the patient's head on the bed as well as for the surgeon and allows other applications such as sinus surgery.