Search

Liver disease, occurring during pediatric or adult age, is often of undetermined cause. Some cases are probably related to undiagnosed inherited metabolic disorders. Hepatic disorders associated with fructose-1,6-bisphosphatase deficiency, a gluconeogenesis defect, are not reported in the literature. These symptoms are mainly described during acute crises, and many reports do not mention them because hypoglycemia and hyperlactatemia are more frequently in the forefront. Herein, the liver manifestations of 18 patients affected with fructose-1,6-bisphosphatase deficiency are described and the corresponding literature is reviewed. Interestingly, all 18 patients had liver abnormalities either during follow-up (hepatomegaly [n = 8/18], elevation of transaminases [n = 6/15], bright liver [n = 7/11]) or during acute crises (hepatomegaly [n = 10/17], elevation of transaminases [n = 13/16], acute liver failure [n = 6/14], bright liver [n = 4/14]). Initial reports described cases of liver steatosis, when liver biopsy was necessary to confirm the diagnosis by an enzymatic study. There is no clear pathophysiological basis for this fatty liver disease but we postulate that endoplasmic reticulum stress and de novo lipogenesis activation could be key factors, as observed in FBP1 knockout mice. Liver steatosis may expose patients to severe long-term liver complications. As hypoglycemia becomes less frequent with age, most adult patients are no longer monitored by hepatologist. Signs of fructose-1,6-bisphosphatase deficiency may be subtle and can be missed in childhood. We suggest that fructose-1,6-bisphosphatase deficiency should be considered as an etiology of hepatic steatosis, and a liver monitoring protocol should be set up for these patients, during lifelong follow-up.

Obtaining a rapid etiological diagnosis for infants with early-onset rare diseases remains a major challenge. These diseases often have a severe presentation and unknown prognosis, and the genetic causes are very heterogeneous. In a French hospital network, we assessed the feasibility of performing accelerated trio-genome sequencing (GS) with limited additional costs by integrating urgent requests into the routine workflow. In addition to evaluating our capacity for such an approach, this prospective multicentre pilot study was designed to identify pitfalls encountered during its implementation. Over 14 months, we included newborns and infants hospitalized in neonatal or paediatric intensive care units with probable genetic disease and in urgent need for etiological diagnosis to guide medical care. The duration of each step and the pitfalls were recorded. We analysed any deviation from the planned schedule and identified obstacles. Trio-GS was performed for 37 individuals, leading to a molecular diagnosis in 18/37 (49%), and 21/37 (57%) after reanalysis. Corrective measures and protocol adaptations resulted in a median duration of 42 days from blood sampling to report. Accelerated trio-GS is undeniably valuable for individuals in an urgent care context. Such a circuit should coexist with a rapid or ultra-rapid circuit, which, although more expensive, can be used in particularly urgent cases. The drop in GS costs should result in its generalized use for diagnostic purposes and lead to a reduction of the costs of rapid GS.

Background The prevention of work-related musculoskeletal disorders (MSDs) is an important issue for the health of operators, especially when the workload is heavy, such as in drilling activities. Research question This study aimed to propose an objective identification and description of the different phases that comprise a drilling task as well as a biomechanical and ergonomic evaluation of the subjects' overall posture during its effective part. Methods Fourteen healthy subjects performed three successive drillings at two different heights, 130 (H130) and 170 cm (H170) from the ground, of a 3 mm thick steel plate. Kinematic and kinetic data were simultaneously acquired using a Qualisys motion capture system and a force platform. The speed profiles of each body segments and the evolution of the force exerted were analysed to identify the different phases. Then, the average joint angles of the whole body were calculated during the drilling phase for the two heights considered and compared. Finally, the measured postures were qualified through the Rapid Upper Limb Assessment (RULA) score in order to assess the risk of developing MSDs for each condition. Results The drilling task could be divided into five phases whatever the condition: transport, aiming, repositioning, drilling, and return. The increase in height has doubled the duration of the drilling phase while reducing the force exerted by about 30 %. Similarly, height variation significantly influenced the subjects' posture, mainly in the head, trunk and upper limbs, and the RULA scores obtained for conditions H130 and H170 were 6 and 7 respectively. Significance The results indicate, on the one hand, the relevance of coupling kinematic and kinetic data in order to analyse the drilling task and, on the other hand, that operators are exposed to considerable risk of developing MSDs, even at intermediate heights, which increase as the height increases.

International audience; Purpose: Abnormality of the corpus callosum (AbnCC) is etiologically a heterogeneous condition and the prognosis in prenatally diagnosed cases is difficult to predict. The purpose of our research was to establish the diagnostic yield using chromosomal microarray (CMA) and exome sequencing (ES) in cases with prenatally diagnosed isolated (iAbnCC) and nonisolated AbnCC (niAbnCC).Methods: CMA and prenatal trio ES (pES) were done on 65 fetuses with iAbnCC and niAbnCC. Only pathogenic gene variants known to be associated with AbnCC and/or intellectual disability were considered.Results: pES results were available within a median of 21.5 days (9-53 days). A pathogenic single-nucleotide variant (SNV) was identified in 12 cases (18%) and a pathogenic CNV was identified in 3 cases (4.5%). Thus, the genetic etiology was determined in 23% of cases. In all diagnosed cases, the results provided sufficient information regarding the neurodevelopmental prognosis and helped the parents to make an informed decision regarding the outcome of the pregnancy.Conclusion: Our results show the significant diagnostic and prognostic contribution of CMA and pES in cases with prenatally diagnosed AbnCC. Further prospective cohort studies with long-term follow-up of the born children will be needed to provide accurate prenatal counseling after a negative pES result.

International audience; Machine learning (ML) can be used in various ways to improve multi-user multiple-input multiple-output (MU-MIMO) receive processing. Typical approaches either augment a single processing step, such as symbol detection, or replace multiple steps jointly by a single neural network (NN). These techniques demonstrate promising results but often assume perfect channel state information (CSI) or fail to satisfy the interpretability and scalability constraints imposed by practical systems. In this paper, we propose a new strategy which preserves the benefits of a conventional receiver, but enhances specific parts with ML components. The key idea is to exploit the orthogonal frequency-division multiplexing (OFDM) signal structure to improve both the demapping and the computation of the channel estimation error statistics. Evaluation results show that the proposed ML-enhanced receiver beats practical baselines on all considered scenarios, with significant gains at high speeds.

International audience; This article presents a new methodological framework for multimodal observation of digital technologies. It is based on the use of mixed methods developed in the interdisciplinary MAN project founded by CNRS. It focuses on the digital accessibility of older people. The originality of the method lies in the implementation of a method combining qualitative and quantitative measurement to determine relevant indicators. These indicators characterize the person's behavior when using a technology and its usability. We show how these indicators are built, based on the cross-referencing of data. We present the different tools (questionnaire, interviews and technological data recording tools) used in the MAN method in a living laboratory environment controlled with four volunteers. Two use scenarios are proposed to illustrate the method in assessing the accessibility of a tactile application for older people without a digital divide and without disabilities. We present the recorded qualitative and quantitative data and illustrate by an example the unrelatedness of these data through a specific annotation tool.

This article describes the development of a mechanistic model for underpinning the dermal Advanced REACH Tool (dART), an extension of the existing ART model and its software platform. It was developed for hand exposure to low volatile liquids (vapour pressure ≤ 10 Pa at 20°C) including solids-in-liquid products. The model is based on an existing conceptual dermal source-receptor model that has been integrated into the ART framework. A structured taxonomy of workplace activities referred to as activity classes are adopted from ART. Three key processes involved in mass transport associated with dermal exposure are applied, i.e. deposition, direct emission and contact, and transfer. For deposition, the model adopts all the relevant modifying factors (MFs) applied in ART. In terms of direct emission and contact (e.g. splashes) and transfer (e.g. hand-surface contacts), the model defines independent principal MFs, i.e. substance-related factors, activity-related factors, localized- and dispersion control and exposed surface area of the hands. To address event-based exposures as much as possible, the model includes crucial events during an activity (e.g. hand immersions) and translates objective information on tools and equipment (manual or automated) to probable events (e.g. splashes) and worker behaviours (e.g. surface contacts). Based on an extensive review of peer-reviewed literature and unpublished field studies, multipliers were assigned to each determinant and provide an approximated (dimensionless) numerical value. In the absence of (sufficient) evidence, multipliers were assigned to determinants based on assumptions made during discussions by experts in the consortium. A worked example is presented to illustrate the calculation of hand exposure for a specific scenario. The dART model is not yet implemented in the ART software platform, and a robust validation of the model is necessary to determine its predictive ability. With advancing knowledge on dermal exposure and its determinants, this model will require periodic updates and refinements, in addition to further expansion of the applicability domain of the model. © The Author(s) 2019. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Reproducing human dexterity and flexibility in unknown environments is one of the major challenges of robotics. Among the issues related to the use of robots with artificial hands of varying complexity, the definition of their kinematical configuration when grasping an object is one of the most difficult problems. Indeed, it necessitates the consideration of a large number of constraints related to the structure of the hand as well as the object, the requirements of the task and the state of the environment. In this frame, sensing capability is crucial to obtain information about the robot state and the quality of sensory signals that may be noisy or of low precision has to be considered to control efficiently a robotic grasping task. In the literature, several paradigms have been proposed to perform grasp planning. Mainly, they can be divided in three categories: knowledge based grasp planning, geometric grasp planning and sensory driven or learning based grasp planning. Knowledge based grasp planning refers to techniques where posture definition is made according to direct or indirect knowledge in human prehension. In fact, in order to better understand the different parameters involved during grasping, several studies have been conducted to classify human prehension. Their main principle is that prototypical hand shapes are used to perform classes of tasks according to particular hand, environment and task related constraints (Napier, 1956; Iberall et al., 1986; Cutkosky, 1987; Tomovic et al., 1987; Bekey et al., 1993; Iberall, 1997; Saito & Nagata, 1999). These classifications have been intensively used to propose solutions in the robotics field, especially in the frame of artificial intelligence and expert systems (Pook & Ballard, 1993; Kang & Ikeuchi, 1997;). The concept of “assembly plan from observation” states that a robot can perform complicated grasps and manipulations by taking advantage of the human dexterity. Thus, optimal solutions can be obtained by the direct observation of human behavior and the extraction of the appropriate movement features (Jeannerod, 1984; Bard et al., 1991; Lee & Xu, 1996; Becker et al., 1999). These methods are very effective but they need sophisticated motion sensing devices such as datagloves. Moreover, the robot can learn only what is demonstrated and it is difficult to generalize from one task to another. Also, an alternative way to define hand posture is to use the concept of preshaping coming from experimental studies on prehension. In fact, it has been demonstrated (Wren & Fischer, 1995) that, prior to grasping, there is an anticipation of hand opening and orientation which is a function of object and task constraints. Therefore, the grasp planning problem is dramatically simplified by the choice of a finite number of hand preshapes. Then, hand closure schemes are defined in order to achieve grasp from the adequate preshape (Miller and al., 2003).

This paper shows an advanced method that is able to achieve accurate recognition of fear facial emotions by providing quantitative evaluation of other negative emotions. The proposed approach is focused on both a calibration computing procedure and an important feature pattern technique, which is applied to extract the most relevant characteristics on different human faces. In fact, a 3D/2D projection method is highlighted in order to deal with angular variation (AD) and orientation effects on the emotion detection. Using the combination of the principal component analysis algorithm and the artificial neural network method (PCAN), a supervised classification system is finally achieved to recognize the considered emotion data split into two categories: fear and others. The obtained results have reached an encouraging accuracy up to 20° of AD. Compared to other state-of-art and classification strategies, we recorded the highest accuracy of identified fear emotion. A statistical analysis is carried out on the whole facial emotions, which confirms the best classification performance (positive predictive values (PPV) = 95.13, negative predictive values (NPV) = 94.65, positive likelihood ratio (PLr) = 33.9, and negative likelihood ratio (NLr) = 0.054. The confidence interval for both of PPV and NPV is 92–98%. The proposed framework can be easily applied for any security domain that needs to effectively distinguish the fear cases recognition.

Inborn Errors of Metabolism (IEM) are rare and heterogenous disorders. For most IEMs, clinical signs are non-specific or belated. Late diagnosis is frequent, leading to death or severe sequelae. Some IEM induce intermediate metabolites circulating in the blood. They may be detected by tandem mass spectrometry. This method allows the simultaneous detection of many IEM in different metabolic pathways. In France, newborn screening (NBS) program for IEM, limited to phenylketonuria for decades, has been recently extended to medium chain acyl-CoA dehydrogenase deficiency. Rationale, methodology and organization of this new NBS program are described. Seven other IEM (maple syrup urine disease, homocystinuria, tyrosinemia type I, glutaric aciduria type I, isovaleric acidemia, long chain hydroxy-acyl-CoA dehydrogenase deficiency, carnitine uptake disorder) should be screened in the next program extension. Efforts are needed to fully understand the predictive value of each abnormal testing at birth, decrease the false positive rate, and develop the adequate management strategies., Les maladies héréditaires du métabolisme (MHM) sont un groupe de maladies rares et cliniquement hétérogènes. Le retard diagnostique est fréquent, conduisant souvent au décès du patient ou à de graves séquelles. Certaines MHM entraînent l’accumulation de métabolites intermédiaires circulant dans le sang, qui sont détectables par une méthode commune utilisant la spectrométrie de masse en tandem. Cette méthode permet la reconnaissance simultanée de plusieurs de ces maladies affectant différentes voies métaboliques. En France, le programme de dépistage néonatal (DNN) des MHM, longtemps limité à la phénylcétonurie, a récemment été étendu au déficit en déshydrogénase des acyl-CoA à chaîne moyenne (MCADD). Le rationnel, la méthode et l’organisation de ce nouveau DNN sont décrits dans cet article. Sept nouvelles MHM (leucinose, homocystinurie, tyrosinémie de type I, acidurie glutarique de type I, acidurie isovalérique, déficit en déshydrogénase des hydroxy-acyl-CoA à chaîne longue, déficit du transporteur de la carnitine) devraient être dépistées, grâce à une prochaine extension du programme de DNN. Des efforts sont nécessaires pour mieux comprendre et prévoir la signification de chaque test anormal à la naissance, diminuer les taux de faux positifs, et développer les stratégies de prise en charge adéquates.

Aims: This paper presents a H2020 project aimed at developing an advanced space weather forecasting tool, combining the MagnetoHydroDynamic (MHD) solar wind and coronal mass ejection (CME) evolution modelling with solar energetic particle (SEP) transport and acceleration model(s). The EUHFORIA 2.0 project will address the geoeffectiveness of impacts and mitigation to avoid (part of the) damage, including that of extreme events, related to solar eruptions, solar wind streams, and SEPs, with particular emphasis on its application to forecast geomagnetically induced currents (GICs) and radiation on geospace.Methods: We will apply innovative methods and state-of-the-art numerical techniques to extend the recent heliospheric solar wind and CME propagation model EUHFORIA with two integrated key facilities that are crucial for improving its predictive power and reliability, namely (1) data-driven flux-rope CME models, and (2) physics-based, self-consistent SEP models for the acceleration and transport of particles along and across the magnetic field lines. This involves the novel coupling of advanced space weather models. In addition, after validating the upgraded EUHFORIA/SEP model, it will be coupled to existing models for GICs and atmospheric radiation transport models. This will result in a reliable prediction tool for radiation hazards from SEP events, affecting astronauts, passengers and crew in high-flying aircraft, and the impact of space weather events on power grid infrastructure, telecommunication, and navigation satellites. Finally, this innovative tool will be integrated into both the Virtual Space Weather Modeling Centre (VSWMC, ESA) and the space weather forecasting procedures at the ESA SSCC in Ukkel (Belgium), so that it will be available to the space weather community and effectively used for improved predictions and forecasts of the evolution of CME magnetic structures and their impact on Earth.Results: The results of the first six months of the EU H2020 project are presented here. These concern alternative coronal models, the application of adaptive mesh refinement techniques in the heliospheric part of EUHFORIA, alternative flux-rope CME models, evaluation of data-assimilation based on Karman filtering for the solar wind modelling, and a feasibility study of the integration of SEP models.

79% of smartphone users carry their phone 22 hours a day. In this context, the main task worldwide, texting, is performed under a wide range of light and position conditions. The aim of this study was to test the effects of environmental illumination and screen brightness settings on upper limb and axial skeleton parameters. Twelve subjects performed three trials of texting under three experimental positions, two screen luminance settings and three environmental light conditions. 3 D axial skeleton and upper limb angles, smartphone orientation and face-to-smartphone distance were used as dependent variables. High environmental illumination and/or low screen brightness resulted in an increase in interaction time and a reduction in the face-to-smartphone distance by approximately 10%. Subjects attempted to compensate for the unfavourable effects of such light conditions by adopting postures rated 5 in the Rapid Upper Limb Assessment, indicating an increased risk of developing musculoskeletal disorders.

Recently, there has been a proliferation of wirelesscommunication technologies in unlicensed bands for the Internetof Things. A key question is whether these networks can coexistgiven that they have different power levels, symbol periods,and access protocols. The main challenge is to characterizethe impact of mutual interference arising from distinct uncoordinatednetworks. It is known that when interferers forma homogeneous Poisson point process and transmit only on asingle subband, the interference is often well-modeled by theheavy-tailed α-stable distribution. In this paper, we focus onthe scenario where interferers transmit on multiple subbands.Under a policy where each interferer independently accesses eachband with probability p, we provide an exact characterization ofthe interference random vector. Exploiting this characterization,we derive optimal linear combining weights and an analyticalapproximation for the bit error rate (BER), accurate for largetransmit power. A key observation is that the expression for theBER admits an interpretation in terms of an array gain and afractional diversity gain.

Objectives To investigate whether cerebrospinal fluid (CSF) and serum ferritin levels differ between patients with narcolepsy type 1 (NT1) comorbid with restless legs syndrome (RLS) or periodic leg movements during sleep (PLMS), and patients with NT1 or controls without comorbid RLS or PLMS. Methods Sixty‐six drug‐free patients with NT1 (44 males, age 38.5 years [14–81]) were enrolled, including 20 with RLS, 18 with PLMS index ≥15/h (six with both RLS and PLMS). Thirty‐eight drug‐free patients (12 males, age 22.5 years [12–61]) referred for sleepiness complaint, but without central hypersomnia, RLS, PLMS were included as controls. Clinical, electrophysiological and biological (CSF/serum ferritin, orexin [ORX]) data were quantified. Results NT1 patients with and without RLS did not differ for age, gender, and body mass index (BMI). No between‐group differences were found for CSF ferritin, ORX, and serum ferritin levels. No CSF ferritin, ORX, and serum ferritin level differences were found between NT1 patients with and without PLMS, or with RLS or PLMS versus not. CSF‐ferritin levels were not different between NT1 and controls in adjusted analyses. CSF‐ferritin levels in the whole population correlated positively with age, serum‐ferritin, BMI, negatively with ORX, but not with PLMS index. In NT1, CSF‐ferritin levels correlated with age and serum‐ferritin but not with PLMS. Conclusion The absence of CSF ferritin deficiency in NT1 with comorbid RLS or PLMS indicates normal brain iron levels in that condition. This result suggests that the frequent association between RLS, PLMS, and NT1 is not based on alterations in brain iron metabolism, a pathophysiological mechanism involved in primary RLS.

International audience; Active user detection is a standard problem that concerns many applications using random access channels in cellular or ad hoc networks. Despite being known for a long time, such a detection problem is complex, and standard algorithms for blind detection have to trade between high computational complexity and detection error probability. Traditional algorithms rely on various theoretical frameworks, including compressive sensing and bayesian detection, and lead to iterative algorithms, e.g. orthogonal matching pursuit (OMP). However, none of these algorithms have been proven to achieve optimal performance. This paper proposes a deep learning based algorithm (NN-MAP) able to improve on the performance of state-of-the-art algorithm while reducing detection time, with a codebook known at training time.

The corneal surface is an essential organ necessary for vision, and its clarity must be maintained. The corneal epithelium is renewed by limbal stem cells, located in the limbus and in palisades of Vogt. Palisades of Vogt maintain the clearness of the corneal epithelium by blocking the growth of conjunctival epithelium and the invasion of blood vessels over the cornea. The limbal region can be damaged by chemical burns, physical damage (e.g., by contact lenses), congenital disease, chronic inflammation, or limbal surgeries. The degree of limbus damage is associated with the degree of limbal stem cells deficiency (partial or total). For a long time, the only treatment to restore vision was grafting part of the healthy cornea from the other eye of the patient or by transplanting a cornea from cadavers. The regenerative medicine and stem cell therapies have been applied to restore normal vision using different methodologies. The source of stem cells varies from embryonic stem cells, mesenchymal stem cells, to induced pluripotent stem cells. This review focuses on the use of oral mucosa epithelial stem cells and their use in engineering cell sheets to treat limbal stem cell deficient patients.

In this paper, we consider an IoT dedicated network corresponding to a non licensed LoRa Low Power Wide Area Network. The LoRa network operates in the unlicensed 868 MHz band within a total bandwidth of 1 MHz divided into 8 orthogonal channels of 125 kHz each. Despite the high level of interference, this network offers long range communications in the order of 2 to 5 km in urban areas and 10 to 30 km in rural areas. To efficiently mitigate this high level of interference, LoRa network essentially relies on a Chirp Spread Spectrum (CSS) modulation and on repetition diversity mechanisms. The LoRa CSS modulation spreads the signal within a band of 125 kHz using 6 possible spreading factors (from 7 to 12) to target data rates (starting from 5 kbps for the closest node to 300 bps for the furthest ones). The repetition diversity mechanisms enable the data recovery when the transmission is subject to bad channel conditions or/and high interference levels. Although the CSS modulation protects edge-cell's devices from the high level of interference induced by nodes in the proximity of the gateway, it fails to protect nodes at the edge of a given SF region and several trials are required to recover the packet. In this paper, we propose an adaptive multi-channels allocation policy that attributes multiple adjacent channels of 125 kHz for nodes situated at the edge of SF zones. We study the impact of this adaptive sub-band allocation on the gateways' intensities, the rate distribution and the power consumption. Our results are based on a statistical characterization of the interference in the network as well as the outage probability in a typical cell.

Developing tools to predict the force capabilities of the human limbs through the Force Feasible Set (FFS) may be of great interest for robotic assisted rehabilitation and digital human modelling for ergonomics. Indeed, it could help to refine rehabilitation programs for active participation during exercise therapy and to prevent musculoskeletal disorders. In this framework, the purpose of this study is to use artificial neural networks (ANN) to predict the FFS of the upper-limb based on joint centre Cartesian positions and anthropometric data. Seventeen right upper-limb musculoskeletal models based on individual anthropometric data are created. For each musculoskeletal model, the FFS is computed for 8428 different postures. For any combination of force direction and joint positions, ANNs can predict the FFS with high values of coefficient of determination (R2 > 0.89) between the true and predicted data.

Objectives We aimed to compare the use of nine different cardiac troponin (cTn) assays (2 cTnT and 7 cTnI) for the diagnosis of NSTEMI in a single multi-centre population. Design and methods One hundred and fifty-eight patients were included (mean age 60 years, SD 17 years), including 23 patients (14%) with NSTEMI. Results The analytical comparison highlighted a large heterogeneity of cTn assays, as reflected by percentages of patients with detectable cTn, correlation coefficients, Passing-Bablok comparisons and concordance coefficients. Correlations within cTnI assays were good and correlation within cTnT assays was excellent. Diagnostic performances demonstrated that each cTn assay has specific threshold values. Furthermore, some assays (HS-cTnI and T, cTnI-Pathfast and cTnI-Centaur) indicated high sensitivity and negative predictive value using the limit of detection (LoD) diagnostic strategy. For the latter assays, a significant increase in specificity was found when using the 99th percentile or the H0-H3 strategies, in comparison to the LoD strategy. When applying the European Society of Cardiology H0-H3 algorithm, comparable diagnostic performances were obtained. Conclusion All 9 cTn assays indicated overall good diagnostic performances for the diagnosis of NSTEMI in emergency departments when the recommended algorithm based on the variation of cTn value between two measurements at admission and 3 h later was used., Highlights • We compare nine troponin assays for the diagnosis of NSTEMI. • Each cTn assay owns specific thresholds for the ESC H0-H3 algorithm. • All assays present high specificity for NSTEMI diagnosis using H0-H3 algorithm. • Assay-specific threshold and delta change values for each cTn assays are mandatory.

Over the past 4 years, our pediatric orthopedic unit has developed a new hybrid protocol combining the advantages of Ponseti's method and the French functional physiotherapy method. Sixty-one patients (92 feet) completed treatment. Clubfoot was unilateral in 30 (49.2%) patients and bilateral in 31 (50.8%) patients. The mean Dimeglio score at the start of treatment was 13.5/20 (range: 6/20-19/20). All patients had clinical and radiographic follow-up for at least 2 years (range: 2-4 years). If orthopedic treatment was ineffective and feet showed no improvement, further surgery was performed. Posterior release was performed in eight (8.7%) feet. Clinical evaluation at the last follow-up found a mean dorsal flexion of 20°±5° (range: 5°-35°). The hybrid method is a combination approach applying the strengths of Ponseti's method, that is, serial casting, and the French physiotherapy method, that is, manipulations and radiographs, to achieve long-term correction with a foot that is fully functional and pain free.

International audience; Background & aims: Pancreatic ductal adenocarcinoma (PDAC) is associated with the highest incidence of venous thromboembolism (VTE) of any cancer type. However, little is known about risk factors for VTE or its outcomes in patients with PDAC.Methods: We collected data from a prospective, observational study performed at multiple centers in France from May 2014 through November 2018 (the Base Clinico-Biologique de l'Adénocarcinome Pancréatique [BACAP] study) linked to a database of patients with a new diagnosis of PDAC of any stage. Data were collected from 731 patients at baseline and during clinical follow-up or in the event of symptoms. The primary endpoint was the onset of VTE during follow-up. The secondary endpoints were progression-free survival (PFS) and overall survival (OS) times.Results: During a median follow-up of 19.3 months, 152 patients (20.79%) developed a VTE. The median time from PDAC diagnosis to the onset of VTE was 4.49 months. Cumulative incidence values of VTE were 8.07% (95% confidence interval [CI], 6.31-10.29) at 3 months and 19.21% (95% CI, 16.27-22.62) at 12 months. In multivariate analysis, PDAC primary tumor location (isthmus vs head: hazard ratio [HR], 2.06; 95% CI, 1.09-3.91; P = .027) and stage (locally advanced vs resectable or borderline: HR, 1.66; 95% CI, 1.10-2.51, P = .016; metastatic vs resectable or borderline: HR, 2.50; 95% CI, 1.64-3.79; P < .001) were independent risk factors for the onset of VTE. Patients who developed VTE during follow-up had shorter times of PFS (HR, 1.74; 95% CI, 1.19-2.54; P = .004) and OS (HR, 2.02; 95% CI, 1.57-2.60; P < .001).Conclusion: In an analysis of data from the BACAP study, we found that frequent and early onsets of VTE after diagnoses of PDAC are associated with significant decreases in times of PFS and OS. Studies are needed to determine whether primary prophylaxis of VTE in patients with PDAC will improve morbidity and mortality related to VTE. (ClinicalTrials.gov, Number: clinicaltrials.gov as number NCT02818829).

International audience; This paper focuses on random uplink transmissions of a subset of nodes disseminated in a cell. Under the constraints of massive Machine Type Communication (mMTC) in cellular Low Power Wide Area Networks (LPWAN) and Ultra Reliable Low Latency Communications (URLLC), improving the capability of a receiver to detect simultaneously several transmissions with a high probability is important. Considering a very limited coordination between the receiver and the distributed transmitters, the usage of coded Non Orthogonal Multiple Access (NOMA) strategies is seducing. In this framework, we target synchronous direct data transmissions and propose an optimal detector of the active users with channel state information at the receiver limited to statistical knowledge. This algorithm is based on a Maximum Likelihood (ML) detector, under statistical channel knowledge only. We give the formulation of the optimal detector and we evaluate its performance, with different codelengths, code types (random Gaussian and Grassmannian codes) and for various number of antennas at the base station.

This paper proposes areas of improvement for Low Power Wide Area (LPWA) solutions. After recalling the rationale of these systems, it summarizes the main challenges of existing solutions and proposes various improvements at PHY and MAC layer that were investigated in context of the EPHYL project. NB-IoT and LoRa were mostly considered in the analysis of existing techniques, while proposals for improvement address both waveform design and resource allocation strategy. We propose as well introduction of new paradigm such as network coding to benefit of the sparse characteristic of some LPWA use cases. Some of the proposals are validated experimentally in the FIT/CorteXlab environment, offering to the research community a framework to experiment and compare their improvements of LPWA systems.

Hardware imperfections in RF transmitters introduce features that can be used to identify a specific transmitter amongst others. Supervised deep learning has shown good performance in this task but using datasets not applicable to real world situations where topologies evolve over time. To remedy this, the work rests on a series of datasets gathered in the Future Internet of Things/Cognitive Radio Testbed [4] to train a convolutional neural network (CNN), where focus has been given to reduce channel bias that has plagued previous works and constrained them to a constant environment or to simulations. The most challenging scenarios provide the trained neural network with resilience and show insight on the best signal type to use for identification, namely packet preamble. The generated datasets are published on the Machine Learning For Communications Emerging Technologies Initiatives web site (Datasets and usage and generation scripts can also be found there: https://wiki.cortexlab.fr/doku.php?id=tx-id.) in the hope that they serve as stepping stones for future progress in the area. The community is also invited to reproduce the studied scenarios and results by generating new datasets in FIT/CorteXlab.

International audience; As the Internet of Things (IoT) is largely supported by wireless communication networks in unlicensed bands, there has been a proliferation of technologies that use a large variety of protocols. An ongoing challenge is how these networks can coexist given that they have different power levels, symbol periods, and access protocols. In this paper, we study the statistics of interference due to IoT networks that transmit small amounts of data. A key observation is that sets of active devices change rapidly, which leads to impulsive noise channels. Moreover, these devices operate on multiple partially overlapping resource blocks. As such, we characterize the joint distribution and propose a tractable model based on copulas. Using our copula model, we derive closed-form achievable rates. This provides a basis for resource allocation and network design for coexisting IoT networks. I. INTRODUCTION With the increasing scale of wireless network deployments for the Internet of Things (IoT), an ongoing challenge is to ensure that these networks can coexist. A key issue is that interference from a large number of devices, even if they operate at low power levels, can degrade the performance of other communication networks. This means that the interference statistics are difficult to characterize and has lead to a number of experimental studies on the interference in various contexts [1]-[4]. One feature observed in IoT networks is the presence of impulsive interference, where high amplitude interference is significantly more likely than in Gaussian models. This behavior has been observed both in experimental studies [4] and also in theoretical analysis [5], [6]. As a consequence, Gaussian models are often not appropriate and the interference statistics lie in a more general class of models. Introducing non-Gaussian interference models implies that the interference statistics are not simply characterized by their mean and variance. This issue is amplified in settings where a number of frequency bands are used for transmissions. In these cases, the covariance matrix is not sufficient in order to characterize the joint interference statistics over multiple frequency bands. This is particularly evident when the frequency bands used by different users only partially overlap [7], such as in non-orthogonal multiple access (NOMA) schemes [8] including sparse code multiple access (SCMA) [9]. Due to the rich dependence structure possible for the joint distribution of non-Gaussian random vectors, a key question is how it should be modeled. For the purposes of analysis

In this paper we present an Internet-of-Things (IoT) network implementation developed as part of the project “Enhanced Physical Layer for Cellular IoT” (EPHYL), using FIT/CorteXlab radio testbed. The aim of our work is to provide a customizable and open source design for IoT networks prototyping in a massive multi-user, synchronized and reproducible environment thanks to the hardware and software capabilities of the testbed. The massive access feature is managed by emulating several sensors per radio nodes. Two categories of network components are used in our design: a base station unit and a multi-sensor emulator unit. The components are separately hosted in dedicated and remotely accessible radio nodes. Their design features can be illustrated through a live demo, which is also reproducible as it is available for any interested reader.

The human face is viewed as the mirror that reflects the inner feelings of the person and allows us to detect the needs of every person and study his behaviour and requirements. We can also identify the tastes of each person and predict his reaction through facial features. Indeed, the detection, classification, characterization of the face are research areas that have received considerable interest in the recent twenty years. However, most published works in this field study the emotions for a person in an upright posture, which means that the person must perfectly face the camera. The innovation in the present work is to improve the detection of emotions in the case of different face orientations (to the right, left, up and down). Eight-teen feature points that perfectly characterize the human face are firstly calculated. An optimization step is proposed by extracting a set of optimal distances between the facial points as a new set of optimized emotion descriptors. For this reason, we have used a statistical characterization criterion based on the ratio of the intra-class variance. An emotion classification experiment is carried out using a multilayer neural network implemented with a digital signal processing microcontroller.

International audience; In a visible light communications system (VLC), light sources are responsible for both illumination, communications and positioning. These light sources inevitably interfere each others at the receiver. To retain the appealing advantage that VLC systems can reuse existing lighting infrastructure, using an extra network to control or synchronize the light sources should be avoided. This paper proposes an uncoordinated multiple access scheme for VLC systems with positioning capability. The proposed scheme does not require a central unit to coordinate the transmission of the transmitters. Transmitters can be asynchronous with one another and with the receiver. Each transmitter is allocated a unique codeword with L chips for a system with up to (L-1)/2 transmitters where L is prime. Due to the linear growth in complexity with respect to number of transmitters, our proposed scheme is feasible for systems with large numbers of transmitters. Our novel decoder can minimize the effect of additive Gaussian noise at the receiver side. Simulation results show that the proposed decoder outperforms zero-forcing decoder.

International audience; One of the major goals of the 5G technology roadmap is to create disruptive innovation for the efficient use of the radio spectrum to enable rapid access to bandwidth-intensive multimedia services over wireless networks. The biggest challenge toward this goal lies in the difficulty in exploiting the multicast nature of the wireless channel in the presence of wireless users that rarely access the same content at the same time. Recently, the combined use of wireless edge caching and coded multicasting has been shown to be a promising approach to simultaneously serve multiple unicast demands via coded multicast transmissions, leading to order-of-magnitude bandwidth efficiency gains. However, a crucial open question is how these theoretically proven throughput gains translate in the context of a practical implementation that accounts for all the required coding and protocol overheads. In this article, we first provide an overview of the emerging caching- aided coded multicast technique, including state-of-the-art schemes and their theoretical performance. We then focus on the most competitive scheme proposed to date and describe a fully working prototype implementation in CorteXlab, one of the few experimental facilities where wireless multiuser communication scenarios can be evaluated in a reproducible environment. We use our prototype implementation to evaluate the experimental performance of state-of-the-art caching-aided coded multicast schemes compared to state-of-the-art uncoded schemes, with special focus on the impact of coding computation and communication overhead on the overall bandwidth efficiency performance. Our experimental results show that coding overhead does not significantly affect the promising performance gains of coded multicasting in small-scale realworld scenarios, practically validating its potential to become a key next generation 5G technology.

This article takes as its starting point the large corpus of costume drawings contained in the Edmond de Rothschild collection in the Louvre. This corpus represents a significant fraction of the works from the 17th and 18th centuries built up by the collector Claude Pioche du Rondray with the intention of publishing an illustrated history of French spectacle. An attempt is made here to set aside the view that choreographic images from the Ancien Regime cannot be used as a source for understanding the technical aspects of dancing from that time. While accepting that no image can be entirely trustworthy, it is nonetheless the case that the true nature of choreographic art from the reign of Louis XIV can be discovered from the way the skirt is held in the minuet, from the coordination of arms and legs in opposition, and from the double bend of the elbows or the high positioning of the arms. Study of these precise examples also helps to date the introduction of certain dance movements and to clarify certain choreographic descriptions. Thus, in order to select and exploit images of the dance as useful sources of information, this article argues that the scholar must bring together a deep knowledge of technique and a familiarity with the workshop practices used by artists to reduce their production time whether through borrowing postures from other images or making etched silhouettes.

International audience; Introduction: Practice guidelines recommend early physical therapy in intensive care units (ICU). Feasibility, safety and efficacy are confirmed by growing evidence-based data. Purpose: To perform a qualitative systematic literature review on early exercise in ICUs, focused on the subject areas of "how to do", "for which patients" and "for what benefits". Methods: Articles were obtained from the PubMed, Google Scholar, Physiotherapy Evidence Database (PEDro), Embase, CINAHL, CENTRAL, Cochrane and ReeDOC databases. The full texts of references selected according to title and abstract were read. Data extraction and PEDro scoring were performed. Consort recommendations were used for the drafting of the systematic review, which was declared on the Prospero website. Results: We confirm the feasibility and safety of early exercise in the ICU. Convergent evidence-based data are in favour of the efficacy of early exercise programs in ICUs. But the potential benefit of earlier program initiation has not been clearly demonstrated. Our analysis reveals tools and practical modalities that could serve to standardize these programs. The scientific literature mainly emphasizes the heterogeneity of targeted populations and lack of precision concerning multiple criteria for early exercise programs. Conclusion: Changes in the professional culture of multidisciplinary-ICU teams are necessary as concerns early exercise. Physical therapists must be involved and their essential role in the ICU is clearly justified. Although technical difficulties and questions remain, the results of the present qualitative review should encourage the early and progressive implementation of exercise programs in the ICU. (C) 2015 Societe francaise d'anesthesie et de reanimation (Sfar).

In this paper are Shownthe results of a study that aims to find the most orthogonal signals that one can employ in an acquisition scheme based on the slmultaneous emission of coded ultrasound waves. The set of studied signals are obtained from pseudo-random binary sequences modulated using different carriers. The performance of these signals is assessed in terms of the provided temporal. Resoluion, side-lobe level and crosstalk. A jointly optimized modulation/compression technique, that allows overcoming the negative effect of the band-limited ultrasound probe, is proposed to improve the performance of the modulated signals.

International audience; Fast varying active transmitter sets are a key feature of wireless communication networks with very short length transmissions arising in communications for the Internet of Things. As a consequence, the interference is dynamic, leading to non-Gaussian statistics. At the same time, the very high density of devices is motivating non-orthogonal multiple access (NOMA) techniques, such as sparse code multiple access (SCMA). In this paper, we study the statistics of the dynamic interference from devices using SCMA. In particular, we show that the interference is α-stable with non-trivial dependence structure for large scale networks modeled via Poisson point processes. Moreover, the interference on each frequency band is shown to be sub-Gaussian α-stable in the special case of disjoint SCMA codebooks. We investigate the impact of the α-stable interference on achievable rates and on the optimal density of devices. Our analysis suggests that ultra dense networks are desirable even with α-stable interference.

International audience; Background: The link between hs-Tn and infarct size has already been proved in several articles. However few is known about the kinetic of the troponin and its link to the infarct characteristics, likewise MVO. Our primary objective was to study which hs-Tn characterizes the best infarction.Methods and results: We identified 29 consecutive STEMI patients to study. The kinetics of hs-TnT (Roche) and two different TnIs (hs-TnI from Abbott, s-TnI from Siemens) were evaluated for all patients. Area under curves (AUC), first peak (FP) and second peak (SP), for hs-TnT, were compared to IS and MVO size using contrast-enhanced cardiac magnetic resonance. For IS, statistically SP of hs-TnT presented the best correlation compared to other peak values [r = 0.9 vs. 0.73 for FP hs-TnT; vs. 0.69 for hs-TnI; vs. 0.57 for s-TnI; respectively P < 0.01, P < 0.01, P < 0.01]. For MVO size, statistically SP of hs-TnT presented the best correlation compared to other peak values [r = 0.84 vs. 0.75 for FP hs-TnT; vs. 0.72 for hs-TnI; vs. 0.62 for s-TnI; respectively P = 0.01, P < 0.01, P < 0.01]. The best AUC were archived by the hs-TnT (AUC = 0.95) but there were no statistical differences when compared to other hs-Tn AUC.Conclusion: The SP of hs-TnT had the greatest level of correlation and therefore seems to be the best biological parameter to evaluate and characterize infarct size.; Introduction: La relation en troponine hypersensible et taille d’infarctus a été prouvée dans de nombreux articles. Cependant, peu de relations ont été établies entre cinétique de troponine et les caractéristiques de l’infarctus, notamment l’obstruction microvasculaire. Notre objectif principal était d’étudier quelle troponine de haute sensibilité caractérisait le mieux l’infarctus du myocarde.Méthodes et résultats: 29 patients ayant subi un infarctus du myocarde aigu ont été inclus consécutivement dans cette étude. Les cinétiques de la troponine T-hs (Roche) et deux troponines I (hs-TnI de chez Abbott, s-TnI de chez Siemens) ont été évaluées pour tous les patients. Les aires sous la courbe, la valeur du premier pic (PP) et du second pic (SP), pour la troponine T-hs, étaient comparées aux valeurs de taille d’infarctus et d’obstruction microvasculaire mesurées par IRM cardiaque. Concernant la taille de la nécrose, le second pic (SP) de troponine T-hs (hs-TnT) avait la meilleure corrélation en comparaison des autres valeurs de pic (r = 0,9 vs 0,73 pour le PP de hs-TnT ; vs 0,69 pour le pic de hs-TnI ; vs 0,57 pour le pic de s-TnI ; respectivement p < 0,01, p < 0,01, p < 0,01). Concernant la taille de l’obstruction microvasculaire, le SP de hs-TnT présentait la meilleure corrélation également en comparaison des autres valeurs de pics (r = 0,84 vs 0,75 pour PP de hs-TnT ; vs 0,72 pour le pic de hs-TnI ; vs 0,62 pour le pic de s-TnI ; respectivement p = 0,01, p < 0,01, p < 0,01). La meilleure aire sous la courbe de troponine était retrouvée avec la hs-TnT (AUC = 0,95), sans différence significative cependant comparativement aux autres troponines.Conclusion: Le second pic de troponine T-hs semblait être le meilleur paramètre biologique d’évaluation des caractéristiques de l’infarctus du myocarde.

Human motion is an important issue in various medical analyses. In this paper, the application of interest is estimating the orientation of the wrist in indoor and outdoor activities using low cost Inertial Measurement Sensor IMU. We present an orientation estimation using Kalman Filter based on Correntropy Criterion (KFCC). The proposed method uses only the acceleration data in the aim to reduce the computing load with accurate orientation estimation. Optical measurement system has been used to benchmark the performance of the proposed method. Moreover, the KFCC is evaluated in indoor and outdoor activities with static and dynamic motion conditions. The proposed method proves its efficiency and reliability against existing methods.

International audience; Ultra-Narrow-Band has been a promising candidate for low-power long-distance transmissions in the context of IoT. Its radio access is random at time and frequency, and can degrade the network performance. We propose to apply signal combining and interference cancellation technologies across multiple base stations in UNB networks, in order to take advantage of their spatial diversity. We evaluate and compare the performance enhancement of each technology, compared to single BS case. These technologies exploiting multi-BS diversity are proved to be significantly beneficial in improving UNB networks' scalability. We can gain until 28 times better performance with one iteration global SIC. We highlight that these results provide us a choice among the technologies according to the improvement needs and the implementation complexity.

Aging is often associated with loss of independency resulting from the deterioration of the gait quality. In Europe, due to the high proportion of the elderly people (age > 65 years) in the populat...

Fast varying active transmitter sets are a key feature of wireless communication networks with very short transmissions arising in machine-to-machine communications. A consequence is that the interference is dynamic, leading to non-Gaussian statistics. In this paper, we study the behavior of large scale communication networks in the presence of isotropic α-stable interference, which forms a model for dynamic interference. We first characterize the achievable rate of each link by considering a non-Gaussian input distribution, which is shown to outperform a Gaussian input. Moreover, we analyze the area spectral efficiency, which is the total rate per square meter. Our analysis suggests that analogously to the common model of slowly varying active transmitter sets, dense networks maximize the area spectral efficiency.

The purpose of this project was to develop and validate a hand wiping protocol to be used by occupational hygienists, scientists, or other competent persons, measuring skin exposure to lead in workplaces. Inadvertent lead ingestion is likely to occur once the hands of employees have become contaminated. Ideally, a hand wiping protocol should maximize the recovery of lead-based residues present on employees' hands in a cost-effective and reproducible manner. This article describes an effective and practical hand wiping procedure. Here, two standardized protocols (A and B) are designed. Protocol A is a self-wiping protocol requiring employees to wipe their own hands using four separate and successive wipes. Protocol B involves a scientist wiping the hands of employees using four wipes, followed by employees self-wiping their hands using two wipes (total of six wipes). Both protocols are defined by four wipe passes over each hand using Ghost wipes. Because this study took place in the workplace rather than in a simulated laboratory environment, only the relative (i.e., not absolute) removal efficiencies of the hand wiping protocols have been assessed. The two protocols were first evaluated at a double glazing panel manufacturing site where between 248 μg and 4544 μg of lead was found on employees' hands. A statistical analysis (t-test) on the mean relative lead levels recovered in the first parts of the protocols indicated that Protocol A was more efficient than Protocol B (73% for Protocol A vs. 65% for Protocol B). The relative recovery of the combined first two passes against the combined first three passes also confirmed the greater efficiency of Protocol A (83.3% for Protocol A vs. 76.5% for Protocol B). However, lead levels recovered on the fourth pass remain significant at more than 10% of the total recovered loadings. Nonetheless, Protocol A was preferred and further evaluated at a lead battery manufacturing site where between 149 μg and 18,784 μg of lead was found on employees' hands.

This paper presents a full-duplex dual-band orthogonal frequency division duplexing (OFDM) radio architecture that enables the radio transceiver to be more flexible and provides a viable radio link capacity gain. A simple but practical I/Q imbalance estimation and compensation method, based on the frequency-flat-fading behavior of the self-interference channel, is proposed. The performance of the proposed I/Q imbalance compensation method is evaluated by link level simulation conducted with Advanced Design System and Matlab. The co-simulation results show that the proposed radio transceiver could potentially increase the physical layer transmission rate by four times compared with the conventional radio link at the cost of tolerable loss of bit error rate performance. The I/Q imbalance compensation method can effectively compensate both high and low I/Q imbalance without the problem of algorithm convergence.

IF=1.21; International audience; This paper presents a method for simulating the kinematics of the vehicle ingress movement of elderly people and/or people with prostheses (represented by a humanoid mannequin with a head, trunk, pelvis and lower limbs) in variably-dimensioned vehicles, starting from real experimental data. To solve this “complex” problem, we propose a three-stage method. The first stage concerns the construction of an “exploitable” movement database, containing movements resulting from the numerical processing of the ingress movements measured in experiments carried out on two vehicles with 2 distinct geometries. The second stage, consisting of 4 phases, analyzes and automatically identifies the ingress movement strategies. By the end of this stage, 2 ingress strategies and 6 sub strategies were identified. The third stage is the simulation. It uses the results from stages 1 and 2 to simulate the ingress movement of a subject in the database, adopting a given sub-strategy for a vehicle with a different geometry. The simulation of the ingress movement of the same subject but for another vehicle is formulated as an inverse kinematics problem, which is solved by constrained nonlinear programming.Simulations involving elderly people and/or people with prostheses made it possible to validate the proposed method for the two ingress strategies. Despite the differences with the measured movements, the simulated movements conform to the sub-strategies adopted by the subjects during the experiments. Furthermore, the simulations made it possible to partially explain the shifts in strategy of some subjects when they changed vehicles during the experiments. Finally, simulations on fictitious vehicles highlighted some of the limitations of our simulation tool. This study opens several perspectives for future research. For example, we could improve the simulation tool by considering the subjects' intra-individual differences.Relevance to industryThis study can aid ergonomists and car manufacturers to simulate the ingress movement in variably-dimensioned vehicles for elderly and/or prosthesis having persons. The results of the simulations can be used in the products' (Vehicles) evaluation and adaptation processes. The developed methodology can be extended to the simulation of other movements as it can be integrated into digital human models (DHMs) software.

International audience; The FIT/CorteXlab platform is a wireless testbed situated in Lyon, France, where all radio nodes are confined to an electromagnetically (EM) shielded environment and have flexible radio-frequency (RF) front-end for experimenting on software defined radio (SDR) and cognitive radio (CR). A unique feature of this testbed is that it offers roughly 40 SDR nodes that can be accessed from anywhere in the world in a reproducible manner: the electromagnetic shield prevents from external interference and channel variability. In this paper we show why it is important to have such a reproducible radio experiment testbed and we highlight the reproducibility by the channel characteristics between the nodes of the platform. We back our claims with a large set of measurements done in the testbed, that also refines our knowledge on the propagation characteristics of the testbed.

International audience; Thanks to its low energy consumption and very long range (upto 50 km in free-space), ultra-narrow-band transmission (UNB) represents apromising alternative to classical technologies used in cellular networks to servelow-throughput wireless sensor networks (WSNs) and the Internet of things(IoT). In UNB, nodes access to the medium by selecting their frequency ina random and continuous way. This randomness leads to new behavior inthe interference which has not been theoretically analyzed, when consideringthe pathloss of nodes randomly deployed around the receiver. In this paper, inorder to quantify the system performance, we derive and exploit two theoreticalexpressions of the outage probability in a UNB based IoT network, accountingfor both interference due to the spectral randomness and path loss due to thepropagation (with and without Rayleigh fading). This enables us to estimatethe network capacity as a function of the path-loss exponent, by determiningthe maximum number of simultaneous supported nodes. We highlight that thebandwidth should be chosen based on the propagation channel properties.

International audience; UNB (Ultra Narrow Band) stands out as one promising PHY solution for low-power, low-throughput and long-range IoT. The dedicated MAC scheme is RFTMA (Random Frequency and Time Multiple Access), where nodes access the channel randomly both in frequency and in time domain, without prior channel sensing. This blind randomness sometimes introduces interference and packet losses. Hence, in this paper, we propose to use the well-known SIC (Successive Interference Cancellation) to cancel the interference in a recursive way. We provide a theoretical analysis of network performance, when considering jointly SIC and the specific spectral randomness of UNB. We analytically and numerically highlight the SIC efficiency in enhancing UNB system performance.

International audience; The envisioned Internet of Things (IoT) will involve a massive deployment of objects connected through wireless cells. While commercial solutions are already available, the fundamental limits of such networks in terms of node density, achievable rates or reliability are not known. To address this question, this paper uses a large scale Multiple Access Channel (MAC) to model IoT nodes randomly distributed over the coverage area of a unique base station. The traffic is represented by an information rate spatial density ρ(x). This model, referred to as the Spatial Continuum Multiple Access Channel, is defined as the asymptotic limit of a sequence of discrete MACs. The access capacity region of this channel is defined as the set of achievable information rate spatial densities achievable with vanishing transmission errors and under a sum-power constraint. Simulation results validate the model and show that this fundamental limit theoretically achievable when all nodes transmit simultaneously over an infinite time, may be reached even with a relatively small number of simultaneous transmitters (typically around 20 nodes) which gives credibility to the model. The results also highlight the potential interest of non-orthogonal transmissions for IoT uplink transmissions when compared to an ideal time sharing strategy.

International audience; Abstract:In this paper, we address the problem of Multi-View Stereo (MVS) reconstruction of highly regular man-made scenes from calibrated, wide-baseline views and a sparse Structure-from-Motion (SfM) point cloud. We introduce a novel patch-based formulation via energy minimization which combines top-down segmentation hypotheses using appearance and vanishing line detections, as well as an arrangement of creased planar structures which are extracted automatically through a robust analysis of available SfM points and image features. The method produces a compact piecewise-planar depth map and a mesh which are aligned with the scene's structure. Experiments show that our approach not only reaches similar levels of accuracy w.r.t state-of-the-art pixel-based methods while using much fewer images, but also produces a much more compact, structure-aware mesh in a considerably shorter runtime by several of orders of magnitude.

International audience; With the emergence of devices equipped with touchscreen, it is necessary to understand the difficulties older aged adults find for executing the gestures of tactile interaction in order to prevent the digital exclusion of this group of users. The association of the analysis of the users' movements to the study of their interaction with touchscreen provide additional information for the interpretation of the results. In the present study, we recorded the movements of older and younger adults during interaction with a tablet, horizontally placed on a desk. We identified differences in the characteristics of the postures of the users' wrists, particularly a greater angular amplitude for older participants which could explain the longer times and the increased number of errors for this group of users. In this paper, we discuss the usability of tactile interaction from an ergonomic perspective.

SUMMARYThe goal of this study is to investigate the use of emotion as a braking system for wheelchair navigation. In the first part emotion is detected based on ElectroEncephalography (EEG) technology and emotion induction experiments. Using different techniques for features extraction (Welch and Wavelets), selection (Principal Component Analysis (PCA) and Genetic Algorithm (GA)) and classification (Support Vector Machine (SVM), Multi Layer Perceptron (MLP) and Linear Discriminate Analysis (LDA)), the best combination was assigned to Wavelets-GA-MLP. In the second part, in order to validate the impact of emotion as velocity modulator, a comparison between emotion-based and non emotion-based wheelchair navigation scenarios in a simulated environment was conducted. The assessment was based on four parameters: obstacles hit, navigation path, execution time and outbound points of gaze (POG). While the first two emotion introductions showed better results, this was not the case for the third. These findings can be utilized in order to prescribe a suitable wheelchair according to the subject pathology.

This paper proposes a new model called \emph{spatial continuum asymmetric channels} to study the channel capacity region of asymmetric scenarios in which either one source transmits to a spatial density of receivers or a density of transmitters transmit to a unique receiver. This approach is built upon the classical broadcast channel (BC) and multiple access channel (MAC). For the sake of consistency, the study is limited to Gaussian channels with power constraints and is restricted to the asymptotic regime (zero-error capacity). The reference scenario comprises one base station (BS) in Tx or Rx mode, a spatial random distribution of nodes (resp. in Rx or Tx mode) characterized by a probability spatial density of users $u(x)$ where each of them requests for a quantity of information with no delay constraint, thus leading to a requested rate spatial density $\rho(x)$. This system is modeled as an $\infty-$user asymmetric channel (BC or MAC). To derive the fundamental limits of this model, a spatial discretization is first proposed to obtain an equivalent BC or MAC. Then, a specific sequence of discretized spaces is defined to refine infinitely the approximation. Achievability and capacity results are obtained in the limit of this sequence while the access capacity region $\mathcal{D}_\Omega(P_m)$ is defined as the set of requested rates spatial densities $\rho(x)$ that are achievable with a transmission power $P_m$. The uniform capacity defined as the maximal symmetric achievable rate is also computed.