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Convergence of the error in Hanafi-Wold's procedure on the PLS-PM task
No full textInternational audiencePartial least squares path modeling is a statistical method that facilitates examining intricate dependence relationships among various blocks of observed variables, each characterized by a latent variable. The computation of latent variable scores is a pivotal step in this method and it is accomplished through an iterative procedure. Within this paper, we investigate and tackle convergence challenges related to Hanafi-Wold's procedure in computing components for the PLS-PM algorithm. Hanafi-Wold's procedure, as well as alternative procedure, demonstrate the property of monotone convergence when mode B is considered for all blocks combined with centroid or factorial schemes. However, the absence of proof regarding the convergence of the error towards zero in Hanafi-Wold's procedure is a limitation compared to alternative procedure, which possesses this convergence property. Therefore, this paper aims to establish the convergence of the error towards zero in Hanafi-Wold’s procedure
Impact of Hands‐On Training Sessions in Dental Traumatology on the Confidence Levels of Students and Dentists
No full textInternational audienceABSTRACT Background Because of their diversity and complexity, dental traumas require a multidisciplinary approach to ensure optimal management and a favorable dental prognosis. During dental studies in France, students receive theoretical instruction in the diagnosis and treatment of various types of dental trauma. However, only a few students gain exposure to clinical cases, which vary in complexity, while dentists are often faced with traumatic dental situations from the very beginning of their practice. We evaluated the impact of hands‐on training in dental traumatology for students in initial training and for dentists in continuing education. Material and Methods Our prospective, monocentric controlled study aimed to compare the confidence levels of 32 dental students and 15 dentists in handling various traumatic injuries, including direct pulp capping, partial pulpotomy, and temporary reconstruction following a fracture, reimplantation of an avulsed tooth, and splinting before and after a hands‐on training session. Participants in both groups were questioned by survey before and after the hands‐on training session. Results The study showed that the participants' confidence levels improved following practical sessions, especially for students ( p < 0.05). This improvement differed depending on the simulated procedures and the groups surveyed, but the majority of the participants (> 80%) were satisfied with this realist simulation. Conclusion Our results confirm the necessity of having a theoretical and practical training during initial and continuous formation in the field of dental traumatology. We can assume that developing realistic workshops for the participants helped them feel more involved and confident in dental traumatology therapies
Quelles actions pour promouvoir la durabilité auprès des consommateurs ? Une approche segmentée par le profil « responsable » des individus
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Intra-vector infection dynamics challenge how to model the extrinsic incubation period for major arboviruses: dengue, Zika, and chikungunya
No full textInternational audienceArboviruses represent a significant threat to the health of humans, animals, and plants worldwide. Mechanistic modeling has proven useful for elucidating the transmission, anticipating the spread, and predicting the response of arboviruses to control measures. However, most models approximate the intra-vector infection dynamic (IVD), which occurs during the extrinsic incubation period (EIP), by a single stage with an average duration. At the end of this stage, all exposed vectors are expected to become infectious. Strong assumption is hidden behind this: that the EIP is exponentially distributed in the vector population. To assess the validity of this assumption, we developed a stochastic compartmental model that represents successive IVD stages, associated with the crossing or not of the three within-mosquito barriers (infection, dissemination, and transmission). We calibrated the model using an ABC-SMC (Approximate Bayesian Computation - Sequential Monte Carlo) method, which includes model selection. We searched for literature data on experimental infections of Aedes mosquitoes infected by dengue, chikungunya, or Zika viruses. We demonstrated the large discrepancy between the exponential hypothesis and observed EIP distributions for dengue and Zika viruses, and identified more relevant EIP distributions. This work provides a generic modeling framework that can be applied to other arboviruses for which similar data are available. Our model also can be linked to population-scale models to aid future arbovirus control efforts
Etude de l’alimentation totale française 3 (EAT3) - Rapport méthode
No full textCitation suggérée : Anses. (2025). Etude de l’alimentation totale française 3 (EAT3) - Rapport méthode. (saisine2019-SA-0010). Maisons-Alfort : Anses, 90 p
Implementation of sample pooling to strengthen the self-monitoring in the food industry: Case study of mycotoxins in cereals
No full textInternational audienceImplementation of sample pooling strategy in the food chemical surveillance could lead to a strengthening of the food safety by increasing the number of analyzable samples. The analysis of a pool of samples and no longer individual samples was applied to the issue of self-monitoring mycotoxins in cereal-based foods, thanks to a data set provided by the surveillance based on ELISA-kits of two mycotoxins – zearalenone (1121 samples) and ochratoxin A (1601 samples) – in four different types of cereal products. After fitting the distribution of mycotoxin concentrations determined in this product category by a Pareto distribution and considering the measurement error in the decision threshold, numerical simulations of pooling were implemented using the Dorfman-2-step strategy. Simulations showed promising results for three out of the four case-studies of zearalenone and ochratoxin A. While being as sensitive and specific as the current one-by-one system, the pooling approach led to a reduction of the number of analyzes performed by 75 – 87 % in three out of the four case studies. Nevertheless, in unfavorable analytical conditions, the pooling approach can lead to an increase of the total number of analyze
Association between fungal detection, airways inflammation and diagnosis of moderate to severe asthma in horses
No full textInternational audienceAbstract Background Fungi are ubiquitous in horses' environment. Their contribution to the pathophysiology of severe asthma (SA) is acknowledged, while controversies remain for mild–moderate asthma (MA). Objectives We hypothesised that fungi are a risk factor for asthma. Our objective was to compare different combinations of analytical methods (cytology, culture) and sampling sites (tracheal wash (TW), bronchoalveolar lavage fluid (BALF)) in relation to clinical status (control, MA, SA). Study design Prospective cross‐sectional study. Methods The study population included asymptomatic racing horses in the field and horses referred to the hospital for respiratory investigations. Fungi were detected by cytology and identified by mycology on TW and pooled BALF. Chi‐square tests and multivariable logistic regressions were used for prevalence comparison between groups and association with clinical investigations. Results In total 155 horses (85 MA, 35 SA and 35 controls) were included in the study. The overall proportions of fungal detection in TW ranged from 45.7% to 89.4% among groups. The prevalence of fungal detection in BALF was significantly lower by cytology for SA (5.7%) than MA horses (23.6%) and significantly higher by culture for MA horses (31.8%) than controls (8.6%). Fungal detection by culture in BALF was significantly associated with high tracheal mucus score, high neutrophil proportions in BALF and diagnosis of MA. Main limitations Mycology was only performed in pooled BALF, and environment was not sampled. Conclusions Fungi were significantly more prevalent in the airways of MA horses than SA and/or controls. Fungal detection on TW, either by cytology or culture, was uninformative in a clinical context. Fungal detection by culture, but not cytology in BALF was associated with MA
DNA methylation landscapes before and after Pacific Oyster Mortality Syndrome are different within and between resistant and susceptible Magallana gigas
No full textInternational audiencePacific oysters face recurring outbreaks of Pacific Oyster Mortality Syndrome (POMS), a polymicrobial multifactorial disease. Although this interaction is increasingly understood, the role of epigenetics (e.g., DNA methylation) appears to be of fundamental importance because of its ability to shape oyster resistance/susceptibility and respond to environmental triggers, including infections. In this context, we comprehensively characterized basal (no infection) and POMS-induced changes in the methylome of resistant and susceptible oysters, focusing on the gills and mantle. Our analysis identified differentially methylated regions (DMRs) that revealed distinct methylation patterns uniquely associated with the susceptible or resistant phenotypes in each tissue. Enrichment analysis of genes bearing DMRs highlighted that these epigenetic changes were specifically linked to immunity, signaling, metabolism, and transport. Notably, 31 genes with well-known immune functions were differentially methylated after POMS, with contrasting methylation patterns between the phenotypes. Based on the methylome differences between phenotypes, we identified a set of candidate epibiomarkers that could characterize whether an oyster is resistant or susceptible (1998 candidates) and whether a site has been exposed to POMS (164 candidates). Overall, the findings provide a deeper understanding of the molecular in teractions between oysters and POMS infection, opening new questions about the broader implications of epigenetic mechanisms in host-pathogen dynamics and offering promising strategies for mitigating the impacts of this devastating disease. Beyond its biological aspects, this study provides insights into potential epigenetic biomarkers for POMS disease management and targets for enhancing oyster health and productivity