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Investigating the influence of affinity on the gaze behavior of individuals with Autism Spectrum Disorder (ASD) based on their unique autistic traits
No full textInternational audienceAutism spectrum is very wide, but autistic people share some traits such as social or language impairments. Another common characteristic is a strong passion, called an affinity, which can be anything from a movie character to a topic like history, or even a specific object. Numerous testimonies attest to the support provided by affinities for autistic individuals, offering a reassuring space in a sometimes frightening world. Clinical psychologists consider affinities as keys that can unlock language and learning for people with ASD. However, objective evidence of this role is still lacking. In this study, we used eye-tracking technology to explore the visual attention patterns of autistic individuals when presented with their affinity compared to neutral stimuli. We recruited 52 autistic participants and showed them 38 images: 10 featuring their affinity and 28 neutral ones, while recording their eye movements. Eye-tracking data provided crucial insights into how visual attention is modulated by affinities. Our results reveal significant variability in visual engagement depending on the specific autistic traits and affinities of the participants. Some showed heightened visual engagement with affinity images, while others withdrew their gaze. Some exhibited a mixed response, with both increased engagement and gaze withdrawal, and a few showed no difference between the two sets of images. These findings highlight the complex relationship between visual attention and affinities in autistic individuals, highlighting the potential of eye-tracking as a tool for understanding and leveraging these affinities in therapeutic and educational settings
Fe-and Mg-functionalized chicken manure biochar immobilized Cd, Cr, and Pb in aged soil and decreased their leaching into groundwater
No full textInternational audienceThe influence of functionalized biochar on the leachability and bioavailability of metal cations in contaminated soils remains insufficiently explored, particularly under aging conditions and multiple leaching cycles. This study investigated the performance of pristine, Mg-, and Fe-functionalized biochar in reducing the leachability of Cd, Cr, and Pb in co-contaminated soil. Preliminary screening revealed that pristine chicken manure biochar (CB), and Mg (MCB)-, and Fe (FCB)-functionalized biochars were more effective in decreasing metals leachability. Consequently, their effects on metals leachability, bioavailability, and fractionation were evaluated through nine leaching cycles and aging experiments (aged soil for 1, 10, 20, 30, 40, and 50 days). Addition of CB to the soil columns significantly decreased the metals concentrations in the leachate. Specifically, Cd concentration (mg L-1) decreased from 5.84 in CK to 0.41 in FCB, 0.53 in MCB, and 0.52 in CB treatments; Pb concentration (mg L-1) decreased from 114.2 in CK to 4.4 in FCB, 5.9 in MCB, and 10.5 in CB treatments; and Cr concentration (mg L-1) decreased from 34.6 in CK to 1.6 in FCB, 1.8 in MCB, and 3.2 in CB treatments. The FCB and MCB redistributed the metals mobile fraction to the residual fraction thereby reducing their mobilization (CaCl2-extrcated form) and availability (DTPA-extracted form) in the treated soil compared to CK soil. The immobilization effect of FCB and MCB remained stable during aging periods, leaching cycles, and under acidic pH, indicating their strong ability for metal capturing. However, long-term investigation of biochar-immobilized metals in aged soils is needed. These findings confirm that functionalizing CB with Fe and/or Mg effectively immobilized Cd, Cr, and Pb in aged soil, reducing the leaching of these toxic metals into groundwater, making this engineered biochar a viable option for soil remediation
Leveraging Cryptographic Simulator Synthesis for Formally Verifying the FOO E-Voting Protocol
No full textInternational audienceCryptographic proofs proceed in large part by reductions to cryptographic assumptions expressed as games. These reductions rely on simulators which are often tedious to write and involve a significant amount of trivial code. Thus, simulators are only sketched in pen-and-paper proofs, which is error-prone. Mechanized cryptographic proofs remove the risk of errors, but requiring users to explicitly write simulators is an unreasonable burden.In this paper, we consider the problem of simulator synthesis in Squirrel, where cryptographic simulation is expressed as bi-deduction. Although the seminal work on bi-deduction provides a proof system and a simple proof-search procedure for it, we show that it suffers from systematic failures when working with games such as IND-CCA2. We provide a significantly improved procedure, that can re-use oracle calls across recursive iterations, and generates precise invariants to justify it. We implement this procedure in Squirrel and validate it in a proof of ballot privacy for the FOO e-voting protocol, which is the first computational mechanized proof for FOO, and the most complex Squirrel proof to date
Vers un modèle précurseur des changements d'état de l’eau pour la petite enfance : aspects quantitatifs et qualitatif
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Modèle précurseur et compréhension du phénomène de formation des ombres en maternelle
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Comment caractériser l'autonomie, la coopération, la créativité et l'équité sociale et de genre dans des séances d’enseignement orientées investigation en sciences ? Retour sur l’élaboration d’une grille pluridimensionnelle
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Assessing psychological distress among medical students: a systematic review and meta-analysis of tools available
No full textInternational audienceIntroduction: Medical students are reported to experience high rates of psychological distress, including depression, anxiety, stress, and suicide. However, there is no consensus on the tools used to detect these symptoms. This systematic review aims to explore the various tools available for assessing distress in medical students.Materials and methods: A systematic literature review was conducted following an established protocol. Articles were included if they addressed anxiety, stress, or psychological distress in medical students and used validated assessment tools translated into English. A meta-analysis was also conducted on the prevalence of stress and anxiety.Results: One hundred twenty-one articles were included, identifying 22 different tools. The Depression, Anxiety and Stress Scale was the most commonly used tool (21.7%), followed by the General Health Questionnaire and the Perceived Stress Scale (14.7%). Only two of the identified tools, the Medical Student Stressor Questionnaire (5.4%) and the Perceived Medical School Stress (3.9%), were specifically designed for medical students. The meta-analysis revealed a stress prevalence of 47.5% and an anxiety prevalence of 44.6%.Conclusion: There are multiple tools available for assessing psychological distress that are already widely used. The use of a specific questionnaire may not be necessary for this population, as tools designed for the general population can also be used for this specific group. However, specific questionnaires may provide a more accurate indication of the causal factors that require action
Nanoarchitectonics of Pro-Degradative Coating to Enhance Iron Corrosion Behavior and Biosafety for Bioresorbable Cardiovascular Stents
No full textInternational audienceControlling both the resorption rate and the formation of reactive oxygen species (ROS) of biodegradable iron (Fe) remains a central challenge for bioresorbable cardiovascular stents. Here, we introduce an innovative, nanoengineered surface coating strategy to simultaneously accelerate Fe corrosion and suppress ROS generation without altering the bulk Fe materials. Aryl-diazonium salt chemistry (4-cyanobenzene diazonium tetrafluoroborate, DCN) was used to creates robust polyaryl interphases that can immobilize gold nanoparticles (Au NPs) on Fe, establishing nanoscale microgalvanic and catalytic sites. Electrochemical analysis reveals that the coating increases the overall Fe corrosion rate while biasing cathodic oxygen reduction reaction towards the four-electron pathway, thereby reducing peroxide/OH• formation. This mechanism is supported by the remarkably reduced OH• content detected by terephthalateprobe assay. Corrosion metrics show a pronounced, controllable rate enhancement relative to bare Fe, and the post-corrosion exposure interfacial spectroscopy/microscopy verify the persistence of Au NPs, attributed to atomic Fe-FeO-Au interactions and anchoring by the DCN-derived polyaryl layer. Endothelial cells culture indicates favorable adhesion and viability, supporting cytocompatibility of the modified surface. This surface-chemistry-driven mechanism establishes a general interfacial principle for rate-and pathway-control of iron biodegradation, offering a concise route to safer, faster-resorbing Fe-based stents
