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Roadmap for animate matter
No full textInternational audienceAbstract Humanity has long sought inspiration from nature to innovate materials and devices. As science advances, nature-inspired materials are becoming part of our lives. Animate materials, characterized by their activity, adaptability, and autonomy, emulate properties of living systems. While only biological materials fully embody these principles, artificial versions are advancing rapidly, promising transformative impacts in the circular economy, health and climate resilience within a generation. This roadmap presents authoritative perspectives on animate materials across different disciplines and scales, highlighting their interdisciplinary nature and potential applications in diverse fields including nanotechnology, robotics and the built environment. It underscores the need for concerted efforts to address shared challenges such as complexity management, scalability, evolvability, interdisciplinary collaboration, and ethical and environmental considerations. The framework defined by classifying materials based on their level of animacy can guide this emerging field to encourage cooperation and responsible development. By unravelling the mysteries of living matter and leveraging its principles, we can design materials and systems that will transform our world in a more sustainable manner
Strategies to overcome the main challenges of Spark Plasma Sintering process and to design advanced ceramics with tailored properties
No full textInternational audienc
-analogs of rational numbers: from Ostrowski numeration systems to perfect matchings
No full text48 pages, 21 figures, 1 tabl
Amyloid signaling in antiphage defense
No full textInternational audienceImmune regulated cell death (RCD) is a defense strategy common to different domains of life involving purposeful sacrifice of infected cells. In animals and fungi, functional amyloids play a role in the control of RCD as molecular switches activating key cell death effectors, rather than causing direct toxicity as seen with pathological amyloids. Here, we describe a novel amyloid‐based signal transduction mechanism in an antiphage defense system in Escherichia coli. This antiphage abortive infection (Abi) system is mediated by two proteins, Bab and Agp which share a common amyloid motif and are encoded by adjacent genes. Upon phage infection, Agp activates Bab through amyloid signaling, leading to cell death. We determined the structure of the Bab cell death execution domain, which is distantly related to pore‐forming domains present in fungi, animals and plants. We show that Bab and the fungal HET‐S amyloid‐controlled cell death execution protein are functionally interchangeable in their respective roles in antiphage defense and allorecognition. These findings add antiphage defense to the functional repertoire of amyloids
Segmentation de nématodes dans des images de microscopie
No full textInternational audienceCe mémoire parle de la conception d’une application d’intelligence artificielle destinée à détecter et compter automatiquement les nématodes du pin à partir d’images de microscopie. J’y présente comment j’ai généré des données synthétiques, conçu un outil d’annotation pour les biologistes, puis entraîné et amélioré progressivement des modèles YOLO adaptés à cette tâche. L’application que j’ai développée permet de corriger facilement les prédictions, d’enregistrer les annotations et d’alimenter une boucle d’amélioration continue. Ce travail aboutit à un outil fonctionnel qui accélère le comptage en laboratoire et améliore la fiabilité des analyses
Basì (Serra-di-Ferro, Corse-du-Sud) : nouvelles données sur le Néolithique ancien corse
No full textInternational audienc
Further analysis and refinements of the perceived stressors in intensive care units (PS-ICU) scale: a French nation-wide cross-sectional multicentre study
No full textInternational audienceAbstract Background Assessing sources of job stress in intensive care units is a critical issue for preventing many occupational health and care-related issues, such as burnout, voluntary turnover and decrease in quality and safety of care. Accordingly, this French nation-wide multicentre study aims to provide supplementary evidence regarding the validity of a recent tool: the Perceived Stressors in Intensive Care Units (PS-ICU) scale. More precisely, this study has three main objectives: to 1) confirm the metrological properties of the PS-ICU scale on a large sample of professionals; 2) test its measurement invariance between nurses, physicians and residents (initial population targeted by the scale); 3) examine whether the scale would also be suited for use with nursing auxiliaries. In addition, depending on the results (which may suggest the removal of several items), this study offers the possibility to shorten the scale to facilitate its use. Method and results 2241 ICU professionals (1135 nurses, 308 physicians, 179 residents, and 619 nursing auxiliaries; overall participation rate of 58.10%) from 42 ICUs in France, voluntarily completed an online questionnaire collecting socio-demographic data and perceived job stressors (PS-ICU). Exploratory structural equation modelling (ESEM), unidimensional reliability (McDonald’s Omega) and item response theory (IRT) analyses overall confirmed the metrological properties of the scale, while several items were removed and the sixth factor (“lack of support and resources from the organisation”) measured by the scale was revised. Results regarding measurement invariance show that the PS-ICU scale can be used to compare occupational groups, including nursing auxiliaries. Finally, all analyses resulted in a reduction of the scale to a 26-item version. Conclusions The PS-ICU scale, which measures generic and ICU-specific job stress factors, is a valid and reliable scale that can be used to collect data from nurses, physicians and residents, as well as from nursing auxiliaries. With 26 items, it can be used by researchers and managers in ICUs to assess the extent and type of stress factors perceived by healthcare professionals
Éducation à la mixité : et les garçons ?: et si cette éducation auprès des garçons était prioritaire ?
No full textInternational audienceÉducation à la mixité ? Cela concerne les deux moitiés de l'humanité.Donc les filles ... mais aussi (surtout ?) les garçons (et ... c’est rarement envisagé).Copains, frères ou pères, référents éducatifs ont, avons, une influence forte sur ces déséquilibres.Les ``mecs ́ ́ sommes souvent animés de bonnes intentions et mal à l'aise à ce sujet : changeons cel
Polymerization‐Charge Controlled Threshold Voltage Tunability in Organic Electrochemical Transistors
No full textInternational audienceThreshold voltage (V th ) is an important parameter in organic electrochemical transistors (OECTs), which are widely used in bio‐sensing and neuromorphic applications. In bio‐sensors, low V th , consequently near zero gate voltage at transconductance maximum, is appreciated in device/cell interfaces, while in neuromorphic devices, the threshold voltage determines the switching behaviour and energy efficiency of artificial synapses and neurons. In this work, electropolymerization is used to fine‐tune the V th of azidomethyl‐PEDOT based OECTs, a clickable analogue of PEDOT. The tuning is achieved through the control of the deposited charge density in a chronoamperometry mode. Azidomethyl‐PEDOT based OECTs yield similarly high transconductance as PEDOT based ones, while reaching maximum transconductance near zero gate voltage. Comprehensive comparisons with PEDOT based OECTs in terms of morphologies, ion transport and capacitance show that Azidomethyl‐PEDOT forms a thinner and flatter morphology under the same electropolymerization conditions, a contributing factor for its low ion mobility, and in turn the strong dependence of switching speed on the film thickness, revealing the underlying mechanisms for V th tuneability. This approach provides a simple and effective strategy for V th modulation in OECTs in certain organic mixed ionic electronic conductors of particular interest
Characterizing Sustained Arrhythmias in Patients With Arrhythmic Mitral Valve Prolapse
No full textInternational audienceBackgroundArrhythmic mitral valve prolapse (AMVP) is a cause of sustained ventricular tachyarrhythmias (VAs) and sudden cardiac death (SCD), but the arrhythmias remain only partially understood.ObjectivesIn this worldwide collaboration, this study aimed to characterize the VAs occurring in AMVP patients, explore factors associated with various types of sustained VA, and describe common triggering mechanisms.MethodsIn this multicenter retrospective cohort study, we collected patients with AMVP and documented VA. Clinical and imaging data, and detailed data of the arrhythmic events were collected. In addition, electrocardiograms or intracardiac tracings capturing the arrhythmic events were analyzed by a core laboratory.ResultsWe included 225 patients from 35 centers (age 44 ± 17 years, 57% female). Late gadolinium enhancement (LGE) was found in 61%. We collected 278 arrhythmic events, of which ventricular fibrillation (VF) was the most frequent (65%), followed by sustained monomorphic ventricular tachycardia (SMVT; 26%). Triggers were most commonly exercise or stress (37%), but 31% had no discernable trigger. SMVT was associated with increasing age (P = 0.03), family history of SCD (P = 0.03), history of syncope (P = 0.05), and myocardial LGE (P = 0.003). Of the 278 events, 140 (50%) had available tracings, where 25% of events were triggered by a short-coupled premature ventricular contraction. Pause-dependent initiation was most frequent (49%), and more likely to lead to VF than to SMVT (P = 0.01).ConclusionsThe dominant VA in AMVP was VF, although SMVT was also common and associated with older age, family history of SCD, syncope, and myocardial LGE. The most common initiation was pause dependent leading to VF