Mines Saint-Étienne

Fenestrated EndoVascular Aneurysm Repair (fEVAR) has been demonstrated to be an excellent treatment for complex abdominal aortic aneurysms. In addition to the aortic endograft, bridging stent-grafts (SG) are deployed within the renal arteries, resulting in rare but serious renal complications. This study aims to assess renal artery hemodynamic changes post-fEVAR, including the effect of respiration-induced renal deformation. Pre-fEVAR models were segmented from CT scans (patients involved in clinical trial NCT04724863), while post-fEVAR models were created from structural simulations that included respiratory-induced deformation. Computational Fluid Dynamics (CFD) simulations applied inflow velocity waveforms at the supraceliac aorta and Windkessel boundary conditions at the outlets. A dynamic mesh was implemented to reproduce renal deformation during breathing, and inspiration and expiration static configurations were analyzed. Post-fEVAR reduction in renal artery flow was detected, together with recirculation regions near the SG protrusions into the aorta. Higher time-averaged wall shear stress was observed in the unstented section of the renal arteries. The comparison between static and dynamic mesh simulations reveals that renal artery motion has negligible effect on the flow. Finally, velocity fields were compared to metrics used clinically to assess renal stenosis, to build a model for the prediction of renal complications in silico. This study evaluates the impact of renal stenting on flow, accounting for respiratory-induced deformation. It shows a minimal influence on overall hemodynamics, but significant reduction of renal flow post-fEVAR. Future studies should evaluate a patient cohort who experienced renal complications to correlate CFD metrics with post-operative clinical outcomes.

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Noisy environments tend to mask sounds and disrupt animal behaviour. One of the most common responses from many animal species to noise is leaving or avoiding the noisiest parts of their ranges. Individuals may alter their movement patterns, either rapidly moving away or changing routes in response to increased noise levels. Here, we tested whether urban-dwelling pied tamarins (Saguinus bicolor): (1) preferentially used quieter areas within their home range, (2) increase travel speed, and (3) alter routes to avoid noise levels. To achieve this, we followed nine pied tamarin groups in five forest fragments within the city of Manaus, Brazil, recording their locations and levels of associated ambient noise levels. We also estimated fruit availability at random points within the group’s home ranges. We found that pied tamarins use the quieter areas of their ranges more intensively, but only if the fruit availability is high. Furthermore, groups did not increase their travel speed or change turning angles in response to noise alone, but travel speed increase in noisier areas closer to the border of their home ranges. Thus, pied tamarins do seem to use the quieter areas of their home ranges, but do not hurry to reach them unless their location lies closer to their home range borders. This may occur because higher noise levels at home-range borders could diminish intergroup communication effectiveness. In general, we found that pied tamarin’s use of space and movement patterns are soundscape-related but mediated by resource availability and social aspects.

This article presents a systematic review on methods for quantifying three-dimensional, time-resolved (3D+t) deformation and motion of human arteries from Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched Scopus, Web of Science, IEEE Xplore, Google Scholar, and PubMed on 19 December 2025 for in vivo, patient-specific CT or MRI studies reporting motion or deformation of large human arteries. We included studies that quantified arterial deformation or motion tracking and excluded non-vascular tissues, in vitro or purely computational work. Thirty-five studies were included in the qualitative synthesis; most were small, single-centre observational cohorts. Articles were analysed qualitatively, and results were synthesised narratively. Across the 35 studies, the most common segmentation approaches are active contours and threshold, while temporal motion is tracked using either voxel registration or surface methods. These kinematic data are used to compute metrics such as circumferential and longitudinal strain, distensibility, and curvature. Several studies also employ inverse methods to estimate wall stiffness. The findings consistently show that arterial strain decreases with age (on the order of 20% per decade in some cases) and in the presence of disease, that stiffness correlates with geometric remodelling, and that deformation is spatially heterogeneous. However, insufficient data prevents meaningful comparison across methods.

The dislocation rate was similar between single and two-stage revision THA using DMC. Further studies are warranted to highlight the potential benefits of DMC in preventing dislocation in two-stage revision THA.

L’ingénierie des connaissances est une thématique de l’Intelligence Artificielle qui contribue au développement de modèles, méthodes et outils pour l’acquisition, la représentation et l’intégration de connaissances. Sa finalité est la production de méthodes et outils « intelligents », capables d’aider l’humain dans ses activités et ses prises de décisions. La conférence Ingénierie des Connaissances est un lieu d’échanges et de réflexions, de présentation et de confrontation des théories, pratiques, méthodes et outils autour de l’ingénierie des connaissances. Cette communauté prend désormais en compte l’essor des algorithmes d’apprentissage automatique et leurs retombées sur les pratiques individuelles et collectives, tout en conservant l’humain au centre des systèmes de décision exploitant les données et les connaissances. Ce numéro spécial regroupe des versions étendues d’une sélection des meilleurs articles des éditions 2021, 2022, et 2023.

Anterior cruciate ligament (ACL) injury and reconstruction significantly increase the risk of knee osteoarthritis (OA). Biomechanical alterations during walking are frequently suggested contributors to OA development. This systematic review aims to determine the association between walking gait biomechanical changes following ACL injury or reconstruction and the early development of knee OA. Studies were identified from MEDLINE, Web of Science, CINAHL and SPORTDiscus databases searched up to January 2024. Eligible studies included adults (≥15 years) with ACL injury or reconstruction, assessing knee biomechanics during walking compared to healthy controls or the contralateral limb. Outcomes included cartilage changes assessed through imaging techniques or biological markers. Methodological quality was evaluated using the modified Downs and Black checklist. Of the 1221 records identified, four cross-sectional studies (total: 199 participants; mean [SD]: 26.3 [6.4] years old) met the inclusion criteria. Three of the four included studies were conducted on participants who had undergone ACL reconstruction surgery. Two studies were of high methodological quality, one was of moderate quality and one was of low quality. The analysis showed that knee unloading (i.e., reduced knee adduction moment (KAM) and vertical ground reaction forces) was associated with an increase in cartilage MRI T1ρ and T2 relaxation times, suggesting a deterioration in cartilage composition. Reduced gait variability and kinematic alterations (reduced knee excursion, altered knee flexion angles and tibial rotations) correlated with early cartilage biochemical changes detectable through MRI T1ρ, T2 relaxation time. Meta-analysis was not feasible due to heterogeneity in outcomes among studies. The included studies demonstrated significant associations between altered gait biomechanics and cartilage degradation. Biomechanical factors such as reduced KAM or reduced knee flexion angle during gait could serve as early indicators for OA risk and inform targeted rehabilitation interventions. Level III.

Many factors can influence how we touch surfaces, where we adapt our finger exploration strategy to the task, material properties, and texture. We studied the influence of finger movement direction, i.e. anteroposterior or lateral, on friction-induced vibrations during touch and perceptual discrimination differences of spatial periods. Three experiments were carried out: two investigating the vibrations induced in the finger, during different sliding velocities and also in changing the investigated textile surfaces, finger angle, velocity, and normal force, as well as a third experiment investigating the perceptual discrimination of textured surfaces. We found that finger vibrations during moving touch were consistently larger in the anteroposterior dimension, especially for frequencies higher than 100 Hz, regardless of the condition or surface. However, for frequencies below 60 Hz, finger vibrations were smaller, similar or greater in the anteroposterior dimension depending on finger velocity, where the velocity equality threshold for movement direction effect was approximately 40 mm/s. In terms of perception, small differences in spatial periods, i.e. 100 or 200 µm, were better discriminated using lateral movements, while discrimination was significantly better using anteroposterior movements for larger spatial period differences, i.e. 300 µm. These results can be explained by different psychometric curves for the movement direction, representing the response level relative to spatial period differences, where the slopes of the discrimination threshold differ between the anteroposterior and lateral directions. These results are discussed relative to the different vibrational behaviours in anteroposterior and lateral movements due to the influence of fingerprints and arm biomechanical behaviour.