Nantes Université
  • Nantes, France
Recent publications
The current study investigates the effect of three foreign language learner emotions on the amount of gain in oral proficiency over one school year of 159 eleven-year-old pupils starting English foreign language classes in France. Previous cross-sectional studies have shown positive relationships between foreign language enjoyment (FLE) and various performance and achievement measures, aswell as negative relationships between foreign language classroom anxiety (FLCA), foreign language classroom boredom (FLCB), and FL performance and achievement measures. A common finding is that negative emotions explain more variance in Foreign Language (FL) performance and achievement measures at a single point in time than positive emotions. Correlation analyses revealed that the amount of gain was positively linked to FLE and negatively linked FLCA and FLCB. A first multiple regression analysis showed that, surprisingly, FLE was the only (positive) predictor of gain in oral proficiency. A second multiple regression analysis revealed that the FLE teacher dimension was the only predictor of gain in oral proficiency. This suggests that positive emotions, and especially the ability of teachers tomeet the psychological needs of their students, have a stronger long-term effect while negative emotions are more likely to disrupt performance in the moment. Pedagogical implications are presented.
Objectives Pulmonary arterial hypertension (PAH) is a rare disease that may be associated with connective tissue diseases (CTD). Anti-fibroblast (AFA) and anti-endothelial cell autoantibodies (AECA) have been identified in idiopathic and systemic sclerosis (SSc)-associated PAH. The aim was to identify autoantibodies discriminating for PAH associated with systemic lupus erythematosus (SLE), mixed connective tissue disease (MCTD) and primary Sjögren's syndrome (SS), and their target antigens. Methods Sera were collected in the French multicentre Auto-HTAP study from 86 patients with CTD excluding SSc, including 32 with PAH (PAH+) and 54 without (PAH–). AFA and AECA were identified using one (1D) and two dimensions (2D) immunoblots and proteomics. ELISA tests using human recombinant proteins were used to confirm PAH-associated IgG reactivities. Results PAH+ patients had similar IgG AFA and AECA reactivities in 56.2% and 40.6% of the cases in 1D immunoblots, respectively. In 2D immunoblots, serum IgG pools from SLE patients (n = 14), MCTD (n = 10), SS (n = 9) and 14 healthy controls (n = 1) recognized respectively 273 ± 79, 205 ± 77, 109 ± 11 and 109 protein spots in fibroblasts and 189 ± 48, 146 ± 30, 88 ± 33 and 190 protein spots in endothelial cell extracts. Serum IgG from PAH+ patients recognized 39 fibroblast and 34 endothelial cell protein spots that were not recognized by IgG from PAH– patients, including Annexin A5 (ANXA5). Anti-ANXA5 IgG reactivity was significantly higher in PAH+ compared with PAH– patients with MCTD (73% vs 0%, p< 0.001) and SLE (33% vs 0%, p= 0.009). Conclusion Anti-ANXA5 IgG autoantibody reactivity might represent a predictive biomarker for PAH associated with MCTD and SLE.
Importance Rituximab is approved for the treatment of moderate to severe pemphigus. However, 20% of patients in the RITUX 3 trial relapsed within the first year of treatment. Objective To assess the outcome of an additional rituximab infusion at month 6 in patients with pemphigus who were in complete remission (CR) after rituximab regimen but had 1 or more predictors of relapse at month 3. Design, Settings, and Participants This multicenter cohort study was conducted in France from September 2018 to June 2023 to assess patients with newly diagnosed pemphigus who were in CR after treatment with the RITUX 3 regimen but had predictors of relapse at month 3. Relapse factors were a Pemphigus Disease Area Index (PDAI) score of 45 or higher, desmoglein 1 (DSG1) antibodies greater than 20 IU/mL, and/or DSG3 antibodies greater than 130 IU/mL. Exposure Patients in CR at month 6 with at least 1 predictor of relapse were treated with an additional rituximab infusion at month 6. Main Outcomes and Measures Primary end point was the rate of CR without corticosteroid therapy for 2 months at month 12. Secondary end points were the rate of relapse, number of patients needing to be re-treated (NNT) with rituximab to avoid a relapse, and safety. Results The study population comprised 87 patients (44 females [50.6%] and 43 [49.4%] males), with a mean (SD [range]) age of 55.3 (15.2 [24-92]) years at pemphigus diagnosis. Of these, 64 patients (73.6%) had pemphigus vulgaris and 23 (26.4%) had pemphigus foliaceus. At month 6, CR had been achieved by 77 patients (88.5%), and 10 (11.5%) had persistent disease activity. Of the 77 patients in CR, 30 (39.0%) had at least 1 predictor of relapse and received an additional infusion of rituximab; 47 patients (61.0%) without a predictor did not. Two patients without a predictor and no patients with a predictor experienced relapse—an overall relapse rate of 2.6% and an NNT of 3.6 (95% CI, 1.6-46.5). The 10 patients (11.5%) with persistent disease activity at month 6 were re-treated with rituximab, 1000 mg. At month 12, the rate of CR without corticosteroid therapy for a minimum of 2 months was 72 of 77 (93.5%) among patients who had achieved CR at month 6, and 72 of 87 (82.7%) for the whole study population. Eight serious adverse effects were reported among 5 patients; there were no deaths. Conclusion and Relevance This multicenter cohort study indicates that using predictors such as baseline PDAI score, anti-DSG1 antibodies, and/or anti-DSG3 antibodies to initiate preemptive treatment with additional rituximab may reduce the rate of short-term relapse.
Purpose Therapeutic administration of ⁹⁰Y-loaded microspheres is routinely used for primary and secondary liver tumours. For activity-based therapeutic prescription the activity must be within 10% of the intended activity. Previous studies reported significant discrepancies between manufacturer-declared vial activities and both experimental and Monte-Carlo assessments, greater than 10%, for resin/glass ⁹⁰Y-microspheres. The objective of this work was to investigate whether these discrepancies were also seen in patients. Methods We analysed patient ⁹⁰Y-PET reconstructions (99 glass and 15 resin microspheres) from 4 different institutions and 4 different systems. We considered tail-fitting background scaling (TFBS) and absolute scaling (ABS), for scatter correction. Residuals after therapeutic injection were measured. Eighty-one patients were imaged with PET/CT and 33 with PET/MR. The PET measured activity (APET) was assessed in the whole liver. The ratio APET/Acalibrator was calculated for each patient, where Acalibrator was the injected activity measured by the dose calibrator corrected for residual and lung shunt. Results Quantification ratio between calibrators and PET was significantly different from 1, regardless of the scatter correction used. In glass microspheres, the mean APET/CT/Acalibrator was 0.84 ± 0.06 for TFBS and 0.90 ± 0.06 for ABS (0.66 ± 0.09 and 0.76 ± 0.07 for (APET/MR/Acalibrator)). The mean APET/CT/Acalibrator ratio for resin microspheres was 1.16 ± 0.09 for TFBS and 1.30 ± 0.12 for ABS. Conclusions We observed in patients similar activity discrepancies as reported for vials, with a relative difference of 44 ± 16% between glass and resin ⁹⁰Y-loaded microspheres. In ⁹⁰Y hepatic radioembolization, the 10% accuracy prerequisite on knowing the administered therapeutic activity is then unlikely to be met.
This article develops a model of public good provision with social norms determined by network relationships. Individuals' wealth allocation preferences are guided by the benefit they obtain from a private good and a public good, and the social value they receive when following their neighbors in their contribution to the public good. We find conditions under which (i) redistributions of wealth will increase total giving if the transfer goes to the less norm‐conformist agent, (ii) an increase in tastes for conformity of the weak contributors will increase total giving, and (iii) the deletion of a link between two contributors will increase total giving. Subsequently, examples in very small networks allow us to discuss how these results can help policymakers encourage the voluntary provision of public good.
Polycythemia vera (PV) and essential thrombocythemia (ET) are rare myeloproliferative neoplasms (MPN) in children, adolescents and young adults. No recommendations are available concerning these patients’ management. Transposing to children the knowledge established in adult patients is not acceptable. For a better understanding of difficulties encountered by pediatricians and adult hematologists, we conducted a national practice analysis concerning follow-up of patients under 18 diagnosed with ET or PV, in France. Then, we present data from a multicentric, descriptive, retrospective study, including 17 patients with ET or PV, diagnosed under 18, coming from 7 hematopediatric departments in France. Interviewed physicians reported a lack of expertise and theoretical training in the hematological field to diagnose and follow children with MPNs. Data from 17 patients (15 ET, 2 PV) confirmed a high proportion of asymptomatic patients at the time of diagnosis (41%). Proportion of “triple-negative” patients (59%) was higher than in adult cohorts. 60% of patients underwent a bone marrow biopsy and 31% of cases were discussed during a multi-disciplinary staff meeting. 76.5% patients were treated, with a high frequency of antithrombotic and cytoreductive drugs. No complications were observed during the 45 months of median follow-up. Conclusion: Physicians insisted on the need for training. Only the accumulation of descriptions of MPNs in children will lead to a better management of these diseases. Considering the small proportion of pediatric patients with complications after diagnosis, rapid therapeutic de-escalation seems essential to consider during the follow-up in a close collaboration with adult hematologists. What is Known: • Myeloproliferativ neoplams are rare and chronic deseases, most of the time affecting adults but also found in few pediatric patients. • There are no recommendations for the diagnosis, therapeutic management or follow-up of children with polycythemia vera or essential thrombocythemia. What is New: • Find out how adult haematologists and paediatricians feel about the management and follow-up of paediatric patients with myeloproliferative syndrome through a national practice analysis. • Description of the “real life” follow-up of children with polycythemia vera or essential thrombocythemia in France.
Empathic accuracy (EA) is the ability to precisely understand someone else's current thoughts and feelings during an interaction. EA has mostly been studied in adult populations; variations in EA in children/adolescents could be explained by age, developmental changes during childhood, and environmental factors. A systematic review was conducted to synthesize the existing literature on EA in childhood, adolescence, and during parent–child interactions. Following PRISMA guidelines, five electronic databases were searched, yielding 24 references. Most studies were conducted in samples of adolescents. Additionally, the operationalization of EA varied across studies. Although studies showed minor variations of EA with age, there is no clear association of age with EA during childhood. Children and adolescents also achieve similar scores as adults. Additionally, children's and parents' EAs are linked to parents' and children's behaviors during interactions. EA is also associated with gender beliefs: parents and children hold beliefs that girls and mothers should have higher empathy than boys and fathers. It is not possible to determine age variation in EA during childhood. This systematic review highlights a lack of transparent methodologies and specific assessments of EA in children and adolescents in the current literature.
Wind turbine systems are highly nonlinear and time-variable. Under external interference, the normal and stable operation of the system is seriously affected. In addition, the inertia of the wind turbine causes a serious lag in speed tracking. These effects are even more severe for floating offshore wind turbines (FOWT). To solve these problems, this paper proposes a new optimal torque control form and further improves and optimizes it. Firstly, the feedback linearization is used to eliminate the nonlinear part of the system and the time-varying parameters, and a new torque control form is obtained. Then, the adaptive sliding mode is used to further optimize the torque controller to enhance the robustness of the system. Finally, adaptive sliding mode-based feedback linearized optimal torque control (ASMFLOTC) was obtained. ASMFLOTC was applied to the FOWT system to verify the effectiveness of its maximum power point tracking (MPPT) control. The results show that ASMFLOTC can better track the reference speed, effectively reduce the relative error, and improve the utilization rate of wind energy. And from the results, the platform motion of the proposed controller is not significantly different from that of other controllers. The proposed controller does not exacerbate the platform motion while increasing the output power. This shows its feasibility.
Now that fast action is needed to mitigate the effects of climate change, developing new technologies to reduce worldwide carbon footprint is critical. Sodium ion capacitors can be a key enabler for widespread transport electrification or massive adoption of renewable technologies. However, a years‐long journey needs to be made from the first proof‐of‐concept report to a degree of maturity for technology transfer to the market. To shorten this path, this work gathers all the stakeholders involved in the technical development of the sodium ion capacitor technology, covering the whole value chain from academics (TRL 1‐3) and research centers (TRL3‐5) to companies and end‐users (TRL 6‐9). A 360‐degree perspective is given on how to focus the research and technology development of sodium ion capacitors, or related electrochemical energy storage technologies, from understanding underlying operation mechanisms to setting up end‐user specifications and industrial requirements for materials and processes. This is done not only in terms of performance metrics, but mainly considering relevant practical parameters, i.e., processability, scalability, and cost, leading up to the final sustainability evaluation of the whole of the technology by Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) analysis, which is of utmost importance for society and policymakers.
Oysters inhabit a variety of coastal and deep‐sea settings over a wide latitudinal range and have a role as ecosystem engineers. They also represent an important food source for humans since hunter‐gatherer times, which motivates interest in using oyster shells as environmental and life history archives. Still, oysters have often been disregarded in sclerochronology studies, although several methods based on both microtextural and geochemical approaches have successfully been investigated. We review how these methods have been used to improve interpretations of shell records, and we identify knowledge gaps in a variety of disciplines. Those include ecology to study larval dispersal and growth rates; archaeology to determine shell midden constructions and site occupations; and palaeoenvironmental and palaeoclimate reconstructions from tidal to annual timescales. We also suggest standardizing sclerochronology procedures to improve palaeoenvironmental reconstructions and biophysical models on oyster larval dispersal.
The Surface Dust Analyser (SUDA) is a mass spectrometer onboard the Europa Clipper mission for investigating the surface composition of the Galilean moon Europa. Atmosphereless planetary moons such as the Galilean satellites are wrapped into a ballistic dust exosphere populated by tiny samples from the moon’s surface produced by impacts of fast micrometeoroids. SUDA will measure the composition of such surface ejecta during close flybys of Europa to obtain key chemical signatures for revealing the satellite’s composition such as organic molecules and salts, history, and geological evolution. Because of their ballistic orbits, detected ejecta can be traced back to the surface with a spatial resolution roughly equal to the instantaneous altitude of the spacecraft. SUDA is a Time-Of-Flight (TOF), reflectron-type impact mass spectrometer, optimized for a high mass resolution which only weakly depends on the impact location. The instrument will measure the mass, speed, charge, elemental, molecular, and isotopic composition of impacting grains. The instrument’s small size of 268 mm×250 mm×171268 ~\mathrm {mm} \times 250 ~\mathrm {mm} \times 171 mm~\mathrm {mm}, radiation-hard design, and rather large sensitive area of 220 cm² matches well the challenging demands of the Clipper mission.
Ultraviolet (UV) photodetector based on doped ZnO are widely reported in literature. However, their sensitivity is limited due to structural defects and morphology. Herein, we present the fabrication and performance of UV photodetectors based silver (Ag)-doped ZnO nanorods. To improve the performance of UV photodetectors based on ZnO nanorods, in terms of sensitivity and current gain, we explored the impact of low Ag doping on the morphology and optical properties of these nanorods. The ZnO nanorods were grown on glass substrates using a hydrothermal process with varying Ag concentration. The I–V characteristics of the ZnO nanorod photodetectors were analyzed under a bias of 5 V. Notably, the addition of Ag significantly improved the photodetector performance, achieving a 9840% increase in photodetection sensitivity at 375 nm under 0.19 mW/cm2 UV illumination, compared to non-doped ZnO nanorods. Furthermore, the results highlight how Ag doping alters the wavelength of peak photoresponse and reduces the rise and decay time constants of the photocurrent, thus improving device response. These findings demonstrate the potential of Ag doping to address critical limitations in ZnO-based UV photodetectors and pave the way for their integration into advanced optoelectronic applications.
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Laurent Lescaudron
  • INSERM U791-LIOAD
Jean-Claude Amiard
  • UFR des Sciences Pharmaceutiques et Biologiques
Thomas Vallée
  • Institut d'Economie et de Management de Nantes (IAE)
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Nantes, France