Nice Sophia Antipolis University
Recent publications
To achieve fault diagnosis and prognosis, obtaining adequate and reliable life-cycle data is essential. However, this poses a challenge in current high-reliable Internet of Things (IoT) systems. Fortunately, accelerated degradation testing can be employed to overcome this hurdle. Nevertheless, a dependable testing and measuring technique is required to construct an accurate model for accelerated degradation testing. This testing method plays a vital role in evaluating fault diagnosis, prognosis, lifetime, and maintenance decisions for reliable products under operational stress. To ensure effective testing, it is crucial to utilize appropriate models that account for the individual heterogeneity of products. However, the commonly used single stochastic models in accelerated degradation testing overlook the impact of this condition in real-world applications, resulting in mis-specification problem. To address this limitation, we propose a novel mixed stochastic process model that integrates multi-Wiener processes and dynamic weights. In addition, we leverage interval analysis to analyze system lifetime, considering the limited data size. The estimation of unknown parameters in our mixed model is achieved using the Metropolis-Hastings algorithm. By analyzing stress relaxation data from electrical connectors, we demonstrate the superior accuracy of our mixed model over conventional single stochastic models in accelerated degradation testing.
This review aims to explore the growing impact of machine learning and deep learning algorithms in the medical field, with a specific focus on the critical issues of explainability and interpretability associated with black-box algorithms. While machine learning algorithms are increasingly employed for medical analysis and diagnosis, their complexity underscores the importance of understanding how these algorithms explain and interpret data to take informed decisions. This review comprehensively analyzes challenges and solutions presented in the literature, offering an overview of the most recent techniques utilized in this field. It also provides precise definitions of interpretability and explainability, aiming to clarify the distinctions between these concepts and their implications for the decision-making process. Our analysis, based on 448 articles and addressing seven research questions, reveals an exponential growth in this field over the last decade. The psychological dimensions of public perception underscore the necessity for effective communication regarding the capabilities and limitations of artificial intelligence. Researchers are actively developing techniques to enhance interpretability, employing visualization methods and reducing model complexity. However, the persistent challenge lies in finding the delicate balance between achieving high performance and maintaining interpretability. Acknowledging the growing significance of artificial intelligence in aiding medical diagnosis and therapy, and the creation of interpretable artificial intelligence models is considered essential. In this dynamic context, an unwavering commitment to transparency, ethical considerations, and interdisciplinary collaboration is imperative to ensure the responsible use of artificial intelligence. This collective commitment is vital for establishing enduring trust between clinicians and patients, addressing emerging challenges, and facilitating the informed adoption of these advanced technologies in medicine.
The early onset epilepsies encompass a heterogeneous group of disorders, some of which result in drug‐resistant seizures, developmental delay, psychiatric comorbidities, and sudden death. Advancement in the widespread use of targeted gene panels as well as genome and exome sequencing has facilitated the identification of different causative genes in a subset of these patients. The ability to recognize the genetic basis of early onset epilepsies continues to improve, with de novo coding variants accounting for most of the genetic etiologies identified. Although current disease‐specific and disease‐modifying therapies remain limited, novel precision medicine approaches, such as small molecules, cell therapy, and other forms of genetic therapies for early onset epilepsies, have created excitement among researchers, clinicians, and caregivers. Here, we summarize the main findings of presentations and discussions on novel therapeutic strategies for targeted treatment of early onset epilepsies that occurred during the Workshop on Neurobiology of Epilepsy (WONOEP XVI, Talloires, France, July 2022). The presentations discussed the use of chloride transporter inhibitors for neonatal seizures, targeting orexinergic signaling for childhood absence epilepsy, targeting energy metabolism in Dravet syndrome, and the role of cannabinoid receptor type 2, reversible acetylcholinesterase inhibitors, cell therapies, and RNA‐based therapies in early life epilepsies.
SACHA‐France (NCT04477681) is a prospective real‐world study that collects clinical safety and efficacy data of novel anticancer therapies prescribed off‐label or on compassionate use to patients <25 years. From March 2020 until February 2024, 640 patients with solid tumors or lymphomas were included, with 176 (28%) reported objective tumor responses. Centralized medical monitoring of local radiological/functional imaging reports by the SACHA coordinating investigator led to response modification in 45 out of 176 cases (26%), highlighting the relevance of the medical review of study data. We suggest this pragmatic approach for improving clinical trial data when centralized radiological review is not performed.
The mixture theory framework is a powerful way to describe multi-phasic systems at an intermediary scale between microscopic and macroscopic scales. In particular, mixture theory reveals a powerful approach to represent microbial biofilms where a consortium of cells is embedded in a polymeric structure. To simulate a model of microalgal biofilm, we propose an upgraded numerical scheme, consolidating the one proposed by Berthelin et al. (2016) to enforce the volume-filling constraint in mixture models including mass exchanges. The strategy consists in deducing the discrete version of the incompressibility constraint from the discretized mass balance equations. Numerical simulations show that this method constrains the total volume filling constraint, even at the discrete level. Moreover, we add viscous terms in the biofilm model to properly represent biofilms interactions with its fluidic environment. It turns out that a well-balanced numerical scheme becomes of outmost importance to capture the biofilm dynamic when including the viscosity. This modelling upgrade also involves recalibrating model parameters. In particular, the elastic tensors to recover realistic front features. With the new parameters, the numerical set-up becomes more demanding to reach convergence.
This article is a report of the CEMRACS 2022 project, called HIVLASHEA, standing for ”High order methods for Vlasov-Poisson models for sheaths”. A two-species Vlasov-Poisson model is described together with some numerical simulations, permitting to exhibit the formation of a plasma sheath. The numerical simulations are performed with two different methods: a first order classical finite difference (FD) scheme and a high order semi-Lagrangian (SL) scheme with Strang splitting; for the latter one, the implementation of (non-periodic) boundary conditions is discussed and different solvers for the electric field are compared. The codes are first evaluated on a one-species case, where an analytical solution is known. For the two-species case, cross-comparisons are performed and the numerical convergence of the SL method is investigated. The use of high order method is emphasized in this context. The (parallel) SL code turns out to be a robust tool to provide reliable numerical approximations of sheath stationary solution with realistic physical parameters.
Equimolar oxygen-nitrous oxide mixture (EMONO) is considered as a reference for dental care in children. Completion of dental treatment has usually been used as a criterion to assess EMONO treatment. However, other patient-reported outcomes are needed. We sought to assess the prevalence of complete therapeutic effects (analgesia and anxiolysis) experienced by children during dental care under EMONO and identifying associated factors. A national prospective observational multicentric study was conducted between September 2018 and June 2020 in 13 French university hospitals. Participants were children between 3 and 15 years of age requiring dental care under EMONO. 677 children were analyzed. Anxiolysis and analgesia were experienced by a large majority of patients (86.5% and 79.0%, respectively, and 73% experienced both effects). Several factors were associated with both analgesia and anxiolysis effects: the presence of expected effects (no loss of judgment and slight decrease in level of consciousness), the absence of agitation and distress, a positive perception of EMONO and ethnicity. Most patients benefit from the therapeutic effects (anxiolysis and analgesia) expected by EMONO during dental treatment. It is reassuring to observe that most sociodemographic characteristics and medical history do not seem to influence the effectiveness of care. The study was registered at www.clinicaltrials.gov under the reference number NCT03453411.
This paper proposes an innovative hybrid package integration strategy compatible with silicon-based technologies. It is evaluated beyond 200 GHz by the integration of a WR3 back-to-back waveguide-to-suspended stripline transition designed in BiCMOS technology, relying on metallic split-block package and organic laminate substrate. Simulated insertion loss below 3 dB is observed in the 220–320 GHz frequency band, competing with reported traditional solutions using III–V substrates. The achieved performances lead to promising perspectives for low-cost silicon packaging solutions beyond 200 GHz.
Objectives: Exercise-induced premature ventricular contractions (EIPVC) have been associated with higher mortality, but the association with coronary artery disease (CAD) has not been precisely established. Our objective was to assess in a group of subjects with EIPVC and cardiovascular risk factors the association with underlying significant coronary artery disease (CAD), in comparison with a control group of patients with cardiovascular risk factors and exercise test (ET) showing ischaemia. Methods: All the patients (above 35 years old) referred for ET at our institution were prospectively included. Patients with at least one cardiovascular risk factor and without known CAD were divided into 2 groups: group A if EIPVC were present (either during exercise or during recovery), at least more than 10% over 30 s of recording; group B if ET was showing ischaemia. The presence of CAD was then confirmed in both groups by coronary arteriography, and/or thallium scintigraphy, and/or cardiac MRI and/or coronary CT angiography performed within 2 months after ET realization. Results: From November 2020 to December 2022, 4098 ETs were performed. After exclusion (normal ETs = 2194; known CAD = 1109; age < 35 years old = 487; congenital heart disease = 59; mitral valve prolapse = 4), 46 patients with EIPVC were finally identified (male 65%, mean age 61.5 ± 11 years), and 71 in group B. CAD was confirmed using additional tests in 5/46 (11%) patients in group A versus 38/71 (54%) in group B (p < 0.0001). Conclusions: Amongst patients without known CAD, the presence of EIPVC was less frequently associated with an underlying CAD, compared to the presence of exercise-induced “electrical” ischaemia.
Acute right colic diverticulitis (ARD) is less frequent in Western countries than acute sigmoid diverticulitis (ASD). We aimed to compare the management of ARD and ASD operated on in emergency. All consecutive patients who had emergency surgery for ASD and ARD (2010–2021) were included in a retrospective, multicenter, cohort study. Patients were identified from databases in French centers that were members of the French Surgical Association. Emergency surgery was performed during the same hospitalization for peritonitis or after failure of conservative treatment. Early and late postoperative outcomes were studied. A total of 2297 patients were included with 2256 (98.2%) ASD and 41 (1.8%) ARD patients. Baseline characteristics were similar. Overall, patients were rated Hinchey 3–4 (63.9%, n = 1468, p = 0.287). ARD was more often treated with resection and anastomosis, protected or not (53.7%, n = 22), whereas ASD was mainly treated with resection and terminal ostomy (62.5% (n = 1409), p < 0.001). Median operative time was shorter for ARD (120 vs 146 min, p = 0.04). The group of ARD patients showed a higher prevalence of Clavien III/IV complications compared to the group of ASD patients, although no statistically significant difference was observed (41.5%, n = 17 vs. 27.6%, n = 620, p = 0.054). However 90-day mortality only happened in ASD patients (9.8%, n = 223 vs 0, p = 0.03). ARD patients had more diverticulitis recurrence (46.3%, n = 19 vs 13.4%, n = 303, p < 0.001). Multivariate analysis identified female sex as a protective factor for recurrence [odds ratio (OR) 0.55, p < 0.001] and ARD as a risk factor (OR 8.85, p < 0.001). Operated on in emergency, ARDs have more resection anastomosis, with a similar rate of complications, less mortality, and more recurrence of diverticulitis than ASD.
Metabolic dysfunction-associated steatotic liver disease (MASLD) is common in individuals with obesity. Sexual dimorphism is present in MASLD. A noninvasive test to diagnose the severity of the disease, in particular the presence of Metabolic dysfunction-associated steatohepatitis (MASH), is lacking. This European multicenter prospective study uses a blood test based on mid-infrared (MIR) metabolic fingerprinting of individuals with severe or morbid obesity to diagnose MASH. Three hundred eighty-two individuals with severe or morbid obesity undergoing bariatric surgery were enrolled prospectively. Liver biopsies were obtained during surgery and assessed centrally. An algorithm was defined to calculate a score from the recorded MIR spectrum and to establish a diagnostic threshold to classify patients with MASH. Among the women (n = 217), MASH was diagnosed in 14.3% of cases. For women, the performance in terms of AUC were 0.83 and 0.82 in the calibration and validation groups, respectively. For a threshold of 0.1817, sensitivities were 86% and 70%, specificities were 81% and 75%, PPV were 43% and 32%, NPV were 97% and 94% and ACC were 82% and 74% for the calibration and validation groups, respectively. For men (n = 78; MASH: 33.3%), the performance of the spectral model was poor. The metabolic fingerprint obtained by MIR spectroscopy can rule out MASH in women with severe or morbid obesity. Its value in men needs new studies. Trial registration: ClinicalTrials.gov identifier: ClinicalTrials.gov identifier: NCT03978247 (04/06/2019)
An approach to tackle the classical problem of homography decomposition is presented. The key novelty lies in the design of two deterministic Riccati observers tailored specifically the homography decomposition problem, departing from the conventional frame-by-frame solving approach employed in traditional algebraic methods. By leveraging the temporal correlation within image sequences and harnessing the inherent low-pass response of the observers, the resulting estimates are robust and less susceptible to measurement noise. Furthermore, a comprehensive analysis pointing out sufficient conditions of uniform observability ensuring local exponential stability is conducted. Simulation results demonstrate a broad convergence domain and showcase the effective performance of the proposed observers. Additionally, experimental evidence is provided to illustrate the improved performance compared to classical algebraic solutions.
Lipschütz ulcer (LU) is a condition known for painful vulvar ulcers, typically affecting young women and often linked to infectious agents. Recent reports have indicated a potential connection between LU and COVID‐19 vaccination, particularly after the second or booster doses. This study presents a case of LU following the first dose of tozinameran in a young woman who had a previous SARS‐CoV‐2 infection and investigates similar cases globally. An 18‐year‐old woman experienced vulvar pain and ulcers 2‐days after her initial COVID‐19 vaccine dose. After ruling out infections through serological tests, a diagnosis of LU was made, and her symptoms resolved after 10 days. A literature search and VigiBase® analysis revealed 11 cases of LU following COVID‐19 vaccination, and 519 vulvovaginal ulcer cases associated with these vaccines were identified in Vigibase®, with a median onset of 2 days. Most LU cases occurred after the second dose or booster shots. The primary hypothesis for this association is a type 3 hypersensitivity reaction mediated by immune complexes, possibly triggered by prior exposure, as many cases occurred after the second dose. Interestingly, the presented case suggests that prior COVID‐19 infection could serve as sensitization. In conclusion, this study highlights the potential occurrence of LU after the initial COVID‐19 vaccine dose in young patients with prior COVID‐19 infection. While the risk of recurrence after subsequent vaccinations or infections remains uncertain, the benefits of vaccination outweigh the risks. Clinicians and patients should be aware of this potential issue to make informed decisions regarding vaccination.
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4,011 members
Philippe R Franken
  • Faculty of Medicine
Bernard Moussian
  • Institut Sophia Agrobiotech (UMR ISA 1355 INRA / UNS / 7254 CNRS)
Pascal Staccini
  • Risk Engineering and Medical Informatics
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Nice, France
Head of institution
Pr. Frédérique Vidal