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Monofocal Nonbacterial Osteitis of the Distal Radius in Children: A Case Report
No full textInternational audienceIntroduction: Chronic bacterial osteitis is a rare inflammatory disease in children that can mimic certain tumor lesions, particularly eosinophilic granuloma. Forms localized to a single site, particularly at the lower end of the radius, are uncommon and make the diagnosis difficult.Observation: A 7-year-old girl was referred for chronic pain in her right forearm. X-rays showed a metaphyseal cystic lesion of the lower end of the radius, associated with significant thinning of the cortex. Magnetic resonance imaging initially suggested an eosinophilic granuloma due to a well-defined lesion, with hypersignal on water-sensitive sequences and hyposignal on T1-weighted sequences, without collection or soft tissue invasion.This suspicion of a tumor led to a bone biopsy. The examination revealed a weakened cortex containing a clear, non-hematic fluid. The pathological study revealed non-specific inflammatory osteitis, and microbiological samples were negative, leading to a diagnosis of chronic non-bacterial osteitis.Treatment with anti-inflammatory drugs led to rapid improvement. Radiology showed gradual filling of the lesion, with complete healing after one year.Conclusion: This observation illustrates a monofocal form of chronic non-bacterial osteitis mimicking an eosinophilic granuloma on imaging. Biopsy remains essential to rule out a tumor or infectious lesion. The prognosis is favorable with anti-inflammatory treatment
Performance Appraisal Methods as Correlate of Lecturers’ Productivity in Universities in Delta State
No full textInternational audienceAims: This study examined performance appraisal methods as correlate of lecturers’ productivity in universities in Delta State. The study was guided by three research questions and three null hypotheses.Study Design: The design of the study was a correlational survey research design.Methodology: The population of the study comprised one thousand nine hundred and nineteen (1919) lecturers in public universities in Delta State. The sample size comprised 236 lecturers in universities in Delta State. The instrument used for data collection was a questionnaire developed by researcher, titled Performance Appraisal Methods and Lecturers Productivity Questionnaire (PAMLPPUQ).). The instrument was subjected to face and content validation and the reliability of the instrument was ascertained through test re-test method and the reliability yielding a coefficient of 0.89. The research questions were answered using the SPSS software, Pearson Product-Moment Correlation Coefficient was employed to answer the research questions. The hypotheses were tested using regression at 0.05 levels of significance.Results: Results of the study, among others, showed that there is a significant relationship between critical incidents, graphic rating scale and essay methods of performance appraisal and lecturers' productivity in public universities in Delta State.Conclusion: Based on the result, it was concluded that the level of lecturers’ productivity was high attesting to the fact that the provision of adequate reward incentives and evaluation based on a fair system of performance standards improves lecturers’ productivity.Recommendations: The study recommended a systematic training and retraining programme for universities management staff and all lecturers should be designed to raise the level of knowledge, when and how to apply the various methods of performance appraisal, such as critical incident, graphic rating scale and essay methods, to enhance lecturers’ productivity
Dieu est-il désenchanté?: Ressources philosophiques et théologico-politiques venant d'Europe
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Investigation of cracking kinetics during cavitation erosion by in-situ X-ray tomography
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On the problem of minimizing the epidemic final size for SIR model by social distancing
No full textInternational audienceWe revisit the problem of minimizing the epidemic final size in the SIR model through social distancing of bounded intensity. In the existing literature, this problem has been considered imposing a priori interval structure on the time period when interventions are enforced. We show that when considering the more general class of controls with an L1 constraint on the confinement effort that reduces the infection rate, the support of the optimal control is still a single time interval. This shows that, for this problem, there is no benefit in splitting interventions on several disjoint time periods. However, if the infection rate is known beforehand to change with time once from one value to another one, then we show that the optimal solution could consist in splitting the interventions in at most two disjoint time periods
Steady-State Cascade Operators and Their Role in Linear Control, Estimation, and Model Reduction Problems
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Breaking objects like Pompeians. The FragEx project and the Porta Nocera necropolis
No full textInternational audienceWithin a given area, multiple activities—whether specialized or mundane—overlap, leaving numerous traces on the ground that can be uncovered through excavation. Given the complexity of this information, it is often assumed that the spatial distribution of these elements is too random to be analyzed as anything other than a single, undifferentiated whole. However, how can we disentangle these traces to identify those corresponding to specific gestures? How can we distinguish objects resulting from deliberate breakage from those that are not? Can particular traces on the objects themselves reveal the gestures of intentional breakage?These questions guided our investigation during the excavation of a sector of the Porta Nocera necropolis in Pompeii. This modest burial site provided an exceptionally well-preserved context, with numerous artefact fragments found on the floor levels. The types of objects recovered resemble those used in commemorative rituals, during which they were either broken or placed in the tomb.To address these questions, we conducted an experiment involving the intentional breakage of archaeological reproductions. This allowed us to observe the traces and dispersion patterns induced by specific gestures. The resulting reference framework can now be applied to identify intentional breakage gestures in archaeological examples
A posteriori-driven adaptive strategy for solving inverse Cauchy problems in diffusion-reaction models
No full textInternational audienceThis work addresses the inverse Cauchy problem for the modified Helmholtz equation using an alternating iterative approach. The central contribution lies in the design of novel local error indicators based on a posteriori analysis, which simultaneously assess the accuracy of the spatial discretization and the convergence behavior of the iterative algorithm. Unlike standard methods, our strategy leverages a comparative assessment of these indicators to drive an adaptive mesh refinement process. This adaptive framework ensures a more balanced distribution of computational resources, significantly reducing the numerical cost while maintaining high solution accuracy. The proposed methodology is validated through a series of synthetic and application-driven numerical experiments, demonstrating both its effectiveness and robustness in reconstructing inaccessible boundary data
GASLEAK: a simulation tool for leak detection of gas pipeline
No full textInternational audienceThe safe and efficient transportation of gases through pipeline networks is a cornerstone of modern infrastructure, supporting industries ranging from energy and chemicals to municipal utilities. However, these systems are inherently susceptible to leaks due to corrosion, mechanical failure, construction defects, or operational errors. Gas leak modeling in pipeline systems is a critical engineering process aimed at predicting, detecting, and mitigating leak scenarios. This involves applying mathematical and physical principles to simulate how a gas, under specific pressure and temperature conditions, escapes from a defect or breach in the pipe wall, and how it subsequently disperses in the surrounding environment. GASLEAK is an in-house software package for modeling gas pipeline systems, including gas flow and leakage in the various components of a transport circuit. It uses a simplified flow model that depends on several hyperparameters, which are adjusted to calibrate the model. Different types of pipe components are represented to capture specific phenomena such as pressure loss or flow loss. Leak types, including internal and external leaks, are also integrated into the component definitions. Before running a simulation, the pipeline model is configured via an input file that describes the gas components and their properties. The output consists of a spatio-temporal simulation of flow and pressure values. The use case presented in the paper focuses on the Jupiter 1000 Power-to-Gas installation in France, which is the leading French industrial demonstrator in this field. A key aspect of the facility involves transporting hydrogen gas. The GASLEAK tool is used to simulate hydrogen flow in the pipeline network, with the main objective of detecting leaks through simulation. In the first stage, the GASLEAK model is calibrated and validated using sensor data collected from the installation. Then, different scenario of the leak in the pipe system is simulated. The simulated results demonstrate the efficiency of the simulation in terms of solution quality as well as time consumption
Assignments and Strategies in Democratic Forking Analysed with
No full textInternational audienceWe consider a recent game theory paper, on democratic forking: suppose you want to go to the opera with a group of 10 friends, with a choice of two operas. Everyone has a preference for one of the operas, but everyone also prefers a large community over a small one. Is there an assignment of each friend to one opera that is stable? The paper answers the question affirmatively giving an algorithm, and also contains results concerning uniqueness of stable assignments and strategyproofness.In previous work, we have formalised the main result of that paper in the proof assistant Isabelle. This provides proofs of the results that are much more reliable, since computer-checked, than paper-and-pencil proofs.Here we continue this formalisation work: we prove that there is a unique stable assignment if voters are sufficiently loyal to some alternative. We show under which conditions an assignment assigning all voters to the same alternative can exist. We refute a theorem stated by previous authors stating that if more than one stable assignment exists, then it is necessarily possible to manipulate the voting process. Finally, we prove that if there is a unique stable assignment, then no manipulation is possible