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Transition numérique et travail décent dans l 'océan indien: Enjeux, vulnérabilités et leviers pour une transformation juste et inclusive
No full textThe digital transition is now a key factor in economic, social, and professional transformations in the Indian Ocean states. This report provides a consolidated regional analysis covering the Comoros, Madagascar, Mauritius, and the Seychelles, linking digital technology, employment, decent work, skills, and information governance. Designed with the priorities of the International Labor Organization (ILO) and the Indian Ocean Commission (IOC) in mind, it aims to inform public policy and regional cooperation dynamics.The approach used is based on a comparative analysis of national contexts and a cross-cutting reading based on a PESTEL grid enriched with an information dimension (PESTEL+I). This makes it possible to integrate issues relating to infrastructure, usage, employment, skills, and public policy, as well as informational vulnerabilities linked to digital platforms, content circulation, and institutional trust.The results show a shared but uneven digital transition, significant potential in terms of employability and the creation of opportunities for young people, but also risks of precariousness and persistent digital divides. The report highlights the emergence of new forms of digital employment (gig economy) and stresses the need to regulate these dynamics within a framework of decent work. Finally, it emphasizes the challenges of information governance, a dimension that is still largely underestimated but central to social cohesion and institutional dialogue.The document sets out five major regional priorities: developing digital skills, reducing divides, supporting new forms of work, strengthening information governance, and creating a regional center of expertise. It frames the digital transition not as a technical objective, but as a matter of social justice, stability, and sustainable development for the Indian Ocean region.La transition numérique constitue aujourd’hui un facteur structurant des transformations économiques, sociales et professionnelles dans les États de l’océan Indien. Ce rapport propose une analyse régionale consolidée portant sur les Comores, Madagascar, Maurice et les Seychelles, en articulant numérique, emploi, travail décent, compétences et gouvernance informationnelle. Conçu dans la perspective des priorités de l’Organisation internationale du Travail (OIT) et de la Commission de l’Océan Indien (COI), il vise à éclairer l’action publique et les dynamiques de coopération régionale.L’approche mobilisée s’appuie sur une analyse comparative des contextes nationaux et sur une lecture transversale fondée sur une grille PESTEL enrichie d’une dimension informationnelle (PESTEL+I). Elle permet d’intégrer à la fois les enjeux d’infrastructures, d’usages, d’emploi, de compétences, de politiques publiques, ainsi que les vulnérabilités informationnelles liées aux plateformes numériques, à la circulation des contenus et à la confiance institutionnelle.Les résultats montrent une transition numérique partagée mais inégale, un potentiel significatif en matière d’employabilité et de création d’opportunités pour les jeunes, mais également des risques de précarisation et de fractures numériques persistantes. Le rapport met en évidence l’émergence de nouvelles formes d’emploi numérique (gig economy) et souligne la nécessité d’encadrer ces dynamiques dans une logique de travail décent. Il insiste enfin sur les enjeux de gouvernance de l’information, dimension encore largement sous-estimée mais centrale pour la cohésion sociale et le dialogue institutionnel.Le document formule cinq orientations régionales majeures : développement des compétences numériques, réduction des fractures, accompagnement des nouvelles formes de travail, renforcement de la gouvernance informationnelle et création d’un pôle régional d’expertise. Il fait de la transition numérique non pas un objectif technique, mais un enjeu de justice sociale, de stabilité et de développement durable pour la région de l’océan Indie
Trajectories and turning points: Objects of intermediation for generalisation
No full textInternational audienceWe introduce generalisation as an intermediated trajectory to explain how system innovations, like alternative food systems, diffuse. While existing literature on diffusion and scaling focuses on human agency and steady progression, we propose a relational, object-oriented approach that highlights the role of situated intermediation punctuating/disrupting trajectories of generalisation. We identify four key objects of intermediation-knowledge, value(s), infrastructures, and rules-and demonstrate their role in reconfiguring actor networks and redirecting transformative trajectories. Through three empirical cases (natural wine, sustainable apiculture, and participatory research in France), we demonstrate how intermediation around these objects resolves challenges (interdependencies, uncertainties, complexities, controversies) and creates turning points that redirect transformative pathways. Our framework integrates the trajectory-turning point model to identify four conditions for transformative change: stability, resistance, identity transformation, and role commitment. Findings reveal that generalisation is dynamic and intermediated, whereby objects and actors collaboratively reconfigure networks, institutional contexts, and innovation objectives. The original contribution of this meso-level perspective lies in theorising generalisation as an intermediated trajectory, emphasising the material and relational work of objects alongside human agency. This reframing advances transition studies and innovation policy research by shifting focus from diffusion mechanisms to the situated, iterative processes that enable systems transformation
Development and assessment of an adhesively bonded assembly geometry adapted for both ELS test and toward hygro-mechanical aging evaluation
No full textInternational audienceStructural adhesive bonding has gained significant attention in recent years. However, its durability in harsh environments, such as marine ones, remains insufficiently examined due to a lack of comprehensive research. One reliable approach for assessing the strength of bonded assemblies is the fracture mechanics, which involves conducting experimental tests in different loading modes to determine their fracture toughness. These tests can be performed before and after aging conditions to evaluate the mechanical properties evolution of the bonded assembly in response to aging. While mode I may occur, mode II is usually dominant in bonded joints; thus, only mode II is considered in this study. The selected mode II test is the End-Loaded Split (ELS) test. Most studies have focused on either the mechanical test setup or the aging setup, but have lacked a combined approach. This paper introduces a new sample configuration that merges both the ELS test setup and the hygro-mechanical frame. To validate the new sample design, a comparison of the fracture toughness values and of the cohesive zone models (CZMs), obtained after fracture data elaboration, is made between this new configuration and a standard ELS sample geometry. For the fracture toughness measurement, all specimens were instrumented with distributed optical fiber sensor to monitor crack propagation as well as Digital Image Correlation system to calculate the J-integral values from which the CZM can be derived. One major conclusion is that the results are repeatable, confirming that the new sample design is valid for the upcoming aging study
Development and laboratory evaluation of a markerless method to estimate low back intersegmental moments in childcare-related activities
No full textInternational audienceIn early childhood care settings, the frequent adoption of awkward postures and repetitive manual material handling tasks are biomechanical risk factors for the development of musculoskeletal disorders. Estimating low back intersegmental moments under realistic conditions could help identify such risks. Realistic conditions make measurement challenging, particularly in achieving a balance between unobtrusive instrumentation and acceptable accuracy. The aim of this study was to develop and evaluate a markerless method for estimating low back intersegmental moments for childcare-related activities. In standardized laboratory conditions, eight participants performed six manual material handling and sit-to-stand tasks, representative of real work situations, using two different baby dummies weighting 2.7 kg and 10 kg. The proposed method, only based on video recordings, was evaluated by comparison with a reference approach combining marker-based motion capture and force platforms. Mean absolute differences in L5/S1 joint moment estimation between both approaches were approximately 20 Nm, which is comparable to errors reported in the literature for methods without force platforms that can be deployed in situ. By requiring no instrumentation or participant preparation, this method offers a practical solution for quantifying low back intersegmental moments
Mission accomplished? A post-assessment of EU ETS impact on power sector emissions reduction
No full textInternational audienceThe debate on the capacity of the European Union Emissions Trading System (EU ETS) to effectively induce CO emissions reduction is still ongoing. This is particularly noteworthy in the case of the power sector, where numerous decarbonization policies overlap. This paper contributes to this discussion by leveraging a methodological approach that circumvents the challenges of constructing credible counterfactuals for causal inference and allows for disentangling the impact of the EU ETS from other measures on the power sector’s abatement efforts, alongside influencing factors such as weather. Specifically, we employ a Bayesian structural time series (BSTS) model, conceptually related to synthetic control techniques, to assess the effectiveness of the three completed phases of the EU ETS (2005-2020) in reducing CO emissions in the power sector across 24 Member States. We analyze the policy implementation effect over the course of each phase by comparing actual power sector emissions with counterfactual estimates derived from contemporaneous predictors related to such emissions. The results indicate a statistically significant emissions reduction in the second and third phases, with no significant reduction in the first phase. The power sector’s centrality to the EU ETS, and its critical role in our economies emphasize the importance of our findings in evaluating emissions reduction objectives
Coarse-to-fine crack cue for robust crack detection
No full textInternational audienceCrack detection is an important task in computer vision. Despite impressive in-dataset performance, deep learning-based methods still struggle in generalizing to unseen domains. The thin structure property of cracks is usually overlooked by previous methods. In this work, we introduce CrackCue, a novel method for robust crack detection based on coarse-to-fine crack cue generation. The core concept lies on leveraging the thin structure property to generate a robust crack cue, guiding the crack detection. Specifically, we first employ a simple max-pooling and upsampling operation on the crack image. This results in a coarse crack-free background, based on which a fine crack-free background can be obtained via a reconstruction network. The difference between the original image and fine crack-free background provides a fine crack cue. This fine cue embeds robust crack prior information which is unaffected by complex backgrounds, shadow, and varied lighting. As a plug-and-play method, we incorporate the proposed CrackCue into three advanced crack detection networks. Extensive experimental results demonstrate that the proposed CrackCue significantly improves the generalization ability and robustness of the baseline methods. The source code is publicly available at https://github.com/LZL501/CrackCue
Patellofemoral alignment safe zones in robotic‐assisted TKA do not affect outcomes but do influence patellar resurfacing rates
No full textInternational audienceAbstract Purpose Anterior compartment management remains a challenging aspect of total knee arthroplasty (TKA), particularly in personalised alignment strategies. This study aimed to assess whether restoring patellofemoral alignment parameters within predefined safe zones—specifically patellar tilt (PTi), patellar translation (PTr) and patellar offset (PO)—is associated with improved clinical outcomes following robotic‐assisted TKA (rTKA). Methods This retrospective study included 283 patients who underwent primary rTKA between March 2021 and January 2023 using functional alignment (FA) or functional knee positioning (FKP) principles. All surgeries were performed using a CT‐based robotic system (Mako, Stryker). Patients were stratified into groups based on radiographic values of PTi, PTr and ΔPO, using thresholds derived from prior robotic studies to define safe zones. Clinical outcomes at a mean follow‐up of 2.8 ± 0.8 years included Knee Society Score (KSS), Forgotten Joint Score‐12 (FJS‐12) and Kujala Anterior Knee Pain Scale (AKPS). Results There were no statistically significant differences in final KSS, FJS‐12 or AKPS between groups within or outside the safe zones for PTi, PTr or ΔPO. However, patients with PTi < 0°, ΔPO > 0 mm (overstuffing) or PTr within ±2 mm showed significantly higher rates of patellar resurfacing ( p < 0.001). No group demonstrated superior clinical outcomes across the three parameters studied. Conclusion Restoring patellofemoral alignment parameters within predefined safe zones was not associated with improved short‐term clinical outcomes in rTKA. Robotic‐assisted FA provides accurate restoration of the anterior compartment, reducing reliance on patellar resurfacing in eligible patients. Our data suggest that target biomechanical parameters can potentially be achieved without resurfacing in cases where it is not indicated. Our hypothesis that patients within the proposed safe zones would demonstrate improved clinical outcomes was not supported by the current results. Further prospective studies are needed to determine whether femoral safe zones can predict long‐term benefit. Level of Evidence Level II
Differences between image-based and imageless robotics for total knee arthroplasty – an overview
No full textInternational audienceRobot-assisted total knee arthroplasty (TKA) has revolutionized implant positioning by enhancing surgical precision. However, significant differences exist between image-based and imageless robotic systems, influencing their accuracy, workflow, and potentially clinical outcomes. As such, this review aims to provide a structured comparison between image-based and imageless systems for TKA relevant to the surgeon. Image-based systems utilize preoperative imaging modalities such as computed tomography (CT) or magnetic resonance imaging (MRI) to construct three-dimensional (3D) anatomical models for surgical planning and intraoperative guidance. In contrast, imageless systems rely on intraoperative anatomical landmark registration, reducing costs and radiation exposure but yielding a potential higher inaccuracy to define the joint-specific coordinate system. This current concepts review examines key differences between these technologies, focusing on coordinate system accuracy, anatomical landmark identification, resection precision, and clinical implications. Image-based systems may demonstrate superior accuracy in defining coordinate systems, particularly for femoral and tibial rotational axes, yet involve higher costs and logistical complexity. Imageless systems offer real-time adaptability and avoid preoperative imaging but may be more susceptible to anatomical registration errors. Comparative clinical studies suggest similar coronal plane alignment error between the two approaches, though image-based systems may offer advantages in tibial slope precision. Radiation exposure is an important consideration, as it varies significantly based on imaging protocols and may warrant greater attention from surgeons, especially for patients who receive frequent CT follow-up. As well, while both system types allow for assessing patellofemoral tracking, in addition patient-specific 3D models allow to restore the native trochlea orientation. Although both systems improve implant positioning compared to conventional techniques, evidence on mid- and long-term improved clinical outcomes compared to the conventional technique is still lacking
Discrete numerical analysis of cohesive granular flow in a thin rotating drum: Flow regimes and cohesion estimation
No full textInternational audienceIn this study, we investigate the rheological behavior of cohesive granular flows within a rotating drum geometry using discrete element method (DEM) simulations. By systematically varying particle size, cohesion, and stiffness, we identify the emergence of distinct flow regimes-consistent with prior experimental observations. While the transitions between these regimes are primarily governed by cohesion, particle stiffness is also shown to significantly influence flow dynamics.To interpret the numerical results, we employ a dimensional analysis rooted in the physics of adhesive particle collisions. This analysis provides a conceptual framework for the remainder of the paper, which explores how "upscaled" discrete simulations can replicate experimental findings and help infer interparticle contact properties such as the adhesive surface energy. Notably, we use it to examine rotating drum experiments involving a unique class of granular materials, ice powders, which holds particular relevance in planetary science applications, and which flowability was shown to be strongly temperature-dependent
Cemented Fixation in Arthroplasty for Hip Fractures Does Not Increase Cardiopulmonary Complications: A Secondary Analysis of the HIP ATTACK Trial
No full textInternational audienceBackground Cemented fixation in arthroplasty to treat hip fractures is now widely recommended, but it is not universally used. Some surgeons may feel that the risk of bone cement implantation syndrome and its cardiopulmonary sequalae are too high, in part, because the evidence provides little detail on postoperative myocardial injury and other medical complications after cement use. Questions/purposes We aimed to use data from the HIP ATTACK trial (an RCT in which patients with a hip fracture were randomized to accelerated time to surgery versus normal timing of surgery) for a secondary analysis to answer the following questions on arthroplasty for patients with hip fractures: (1) Are patients who undergo cemented hip arthroplasty for hip fractures more likely to experience cardiopulmonary events than patients who undergo uncemented hip arthroplasty? (2) Are patients who undergo cemented hip arthroplasty for hip fractures more likely to experience myocardial injury, identified by elevated troponin levels, than patients who undergo uncemented hip arthroplasty? Methods We performed a post hoc analysis of the HIP ATTACK trial for a subset of patients who were treated with THA or hemiarthroplasty for a femoral neck fracture because the trial collected postoperative troponin levels to allow us to identify myocardial injury. The HIP ATTACK trial consisted of 2970 patients. We limited our source cohort to the 1049 patients who underwent hip arthroplasty and were not lost to follow-up (four patients who had undergone arthroplasty were lost to follow-up). We excluded two patients with unknown fixation and six patients with “other arthroplasty.” We limited our analysis to femoral neck fractures, which excluded 75 more patients. Of the 966 patients who received hip arthroplasty, 61% (593) had cemented fixation. Patients with cemented fixation were older than patients with cementless fixation (median [IQR] 82 (74 to 88) versus 79 (71 to 86); p = 0.003). Race was self-reported by patients and differed between patients with cemented and cementless fixation. A higher proportion of patients who received cementless fixation had undergone THA (compared with hemiarthroplasty) than patients in the cemented fixation group (24% [91] versus 11% [66]; p < 0.001). We used logistic regression to estimate the association between cement use and a composite outcome consisting of all-cause mortality and various cardiopulmonary outcomes. We included cardiopulmonary outcomes possibly associated with bone cement implantation syndrome; there were only a small number of patients who had only nonsevere outcomes. We had 80% power to detect an OR of ≥ 1.6. We adjusted for all baseline differences between both groups except for anesthesia (as it was not associated with the outcome) and duration of surgery (as it is a function of cement use). Results After controlling for age, sex, race, and relevant comorbidity, we found that cement use was not associated with differences in the composite outcome at 90 days (OR 1.0 [95% confidence interval (CI) 0.7 to 1.4]; p = 0.99) or 1 year (OR 1.0 [95% CI 0.7 to 1.4]; p = 0.95) or with postoperative elevated troponin (OR 1.4 [95% CI 1.0 to 1.9]; p = 0.06) on Day 1. Conclusion There was no difference in cardiopulmonary outcomes among patients with arthroplasty to treat their hip fracture by fixation method. These findings further support the recommendations to use cemented femoral fixation in THA and hemiarthroplasty for patients with hip fractures. Surgeons with limited experience with cemented femoral fixation should familiarize themselves with these skills. Future studies should assess what barriers to cemented fixation exist and how they can be mitigated. Level of Evidence Level III, therapeutic study