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Error correction in correlative measurement methods
No full textInternational audienceAn experimental study of bubble motion in a bubbling column using shadow visualization is carried out. Error correction in correlation analysis improves the accuracy of bubble velocity measurement. Data accumulation, even at high noise levels, allows the information peak to be isolated and the average bubble popping velocity to be determined with minimal discrepancies between the different processing methods. Data on the bubble size distribution in the bubble column showed that the average bubble diameter in the experiment was 3.1 mm. Velocity distribution data were obtained for the two velocity components revealed that the bubbles move vertically with little or no displacement across the channel width. The obtained average velocity Vy was 0.22 m/s
Diagnosis of hereditary transthyretin amyloidosis in patients with suspected chronic inflammatory demyelinating polyneuropathy unresponsive to intravenous immunoglobulins: results of a retrospective study
No full textInternational audienceAbstract Background and aims Hereditary transthyretin amyloidosis (ATTRv) should be considered in patients diagnosed with intravenous immunoglobulin (IVIg)-resistant chronic inflammatory demyelinating polyradiculoneuropathy (IVIg-NR CIDP). In this 1-year long, retrospective, multicentric study, an online questionnaire was sent to 1100 French healthcare professionals (HCPs) investigating: (i) how many IVIg-NR CIDP patients they followed; (ii) how many IVIg-NR CIDP patients had undergone TTR gene analysis; and (iii) how many IVIg-NR CIDP patients were eventually diagnosed with ATTRv. The questionnaire was sent every 3 months for 1 year and contained information on ATTRv clinical manifestations and diagnosis. Results One-hundred and ten (10%) HCPs responded. A total of 2131 patients with CIDP were identified, including 315 (22.1%) with IVIg-NR CIDP. TTR gene analysis was performed in 144 patients and was positive in 43 cases (29.9%). Conclusions This study demonstrates that ATTRv should be investigated systematically in patients diagnosed with IVIg-NR CIDP. HCP-directed information campaigns are useful for modifying diagnostic practices
How Micro-distances could Influence Electro-coagulation Efficiency in Low-conductivity Solutions?
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ElectRotate as an innovative design for the mineralization of PFOA by advanced electrolytic treatment
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Impact technique et économique des gastro-entérites néonatales chez le veau en élevage laitier : approche par simulation
No full textLes gastro-entérites néonatales infectieuses représentent la principale cause de morbidité et de mortalité chez le veau durant son premier mois de vie. Leur impact économique est lié à la mortalité directe, aux soins, à la baisse de croissance et aux pertes de production laitière ultérieures. Un modèle épidémiologique a été développé dans le simulateur Dairy Health Manager (DHM) afin de représenter l'apparition, l'évolution et les conséquences techniques et économiques de ces affections à partir de données issues de la littérature scientifique. Les agents étudiés incluaient Escherichia coli entérotoxinogène (ETEC), Cryptosporidium parvum, le rotavirus et le coronavirus bovins. Différents scénarios ont été simulés selon les pratiques de prévention modélisées dans le DHM (gestion du colostrum, maîtrise de l'hygiène et vaccination) dans plusieurs situations d'élevage. Les résultats montrent que la meilleure combinaison de mesures de prévention sur les plans technique et économique consiste à avoir une hygiène irréprochable, à tester la qualité du colostrum avec un réfractomètre optique, à porter une attention sur la qualité du colostrum ingérée et sur le temps passé entre la naissance et l'ingestion du colostrum et à vacciner contre ETEC, le rotavirus et le coronavirus bovin. La vaccination n'apporte un gain économique notable qu'en situation d'incidence élevée. L'impact des mesures de prévention est amplifié à mesure que l'incidence augmente. Ces travaux mettent en évidence l'importance de stratégies combinant plusieurs mesures de prévention, adaptées au contexte sanitaire et économique de chaque élevage laitier
Mini-GRID therapy delivers optimised spatially fractionated radiation therapy using a flattening free filter accelerator
No full textInternational audienceBackground: Radioresistant tumours remain a challenge for conventional radiation therapy (RT), and often, only palliative treatment can be offered. Recently developed techniques, such as spatially fractionated radiation therapy (SFRT) could potentially improve treatment. However, current clinical SFRT implementations do not allow the full potential to be exploited. We further optimize SFRT, developing mini-GRID, which uses a flattening free filter accelerator.Methods: The increase in normal tissue tolerances provided by mini-GRID compared to conventional RT and GRID therapy was validated in a rat model of brain irradiation in a longitudinal imaging study, behavioural tests and by histopathological evaluation.Results: The implementation optimizes mini-GRID therapy, with beam widths around 2 mm2. The peak-to-valley dose ratios and peak dose rates are around 4 and 7 Gy/min, respectively. Mini-GRID RT allows the use of high peak doses: 42 Gy in one fraction, a factor more than twice higher than the peak doses generally employed in conventional GRID therapy (20 Gy peak dose). This enables the use of more aggressive and potentially curative treatments. Infrared microspectroscopy analysis suggests different early biochemical changes in both modalities, with conventional RT leading to stronger modifications in the secondary protein structure, and higher oxidative damage than mini-GRID RT.Conclusions: The possibility to treat both large and small tumours, and to perform safe and potentially curative dose escalations in previously untreatable cases, makes mini-GRID a promising approach to expand the clinical use of SFRT
Structural mechanisms of cellulose-based nanocomposites mimicking the structure of articular cartilage under uniaxial compression probed by in situ SAXS
No full textInternational audienceA new method combining frontal ultrafiltration and ultrasound, followed by UV photocrosslinking enabled the fabrication of orthotropic CNC/PEGDA (poly(ethylene glycol) diacrylate) nanocomposites with the structure of articular cartilage. In situ SAXS compression/relaxation mechanical tests demonstrated this orthotropic organization as well as elastic behavior with a Young's modulus of 0.76 MPa, similar to articular cartilage
Opportunities for Hybrid Modeling Approaches in Energy Systems optimization
No full textInternational audienceThis paper surveys the primary computational hurdles of Energy Systems optimization coming from differ-ent sources: model-induced complexity, optimization algorithm requirements, and uncertainties handling (bothaleatoric and epistemic). Techniques to reduce complexity such as time-series and spatial aggregation, model orderreduction, and specialized optimization strategies are reviewed for their effectiveness in balancing computationalfeasibility and model fidelity. Furthermore, Various uncertainty-management frameworks, including scenario-based approaches, robust optimization, and distributionally robust methods, are reviewed and their limitations inscaling and data requirements are discussed. The potential of hybrid modeling emerges as a key avenue: by fusingmechanistic and machine learning elements, hybrid techniques for modelling and optimization can harness thestrengths of both worlds while mitigating their respective drawbacks. The paper highlights several directions forfurther research to develop advanced methods to tackle the complexity of MES
Performance of ChatGPT-4 on the French Board of Plastic Reconstructive and Aesthetic Surgery written exam: a descriptive study
No full textInternational audiencePurposeThis study aims to evaluate the performance of Chat Generative Pre-Trained Transformer 4 (ChatGPT-4) on the French Board of Plastic, Reconstructive, and Aesthetic Surgery written examination and to assess its role as a supplementary resource in helping medical students prepare for the qualification examination in plastic surgery.MethodsThis descriptive study evaluated ChatGPT-4’s performance on 213 items from the October 2024 French Board of Plastic, Reconstructive, and Aesthetic Surgery written examination. Responses were assessed for accuracy, logical reasoning, internal and external information use, and were categorized for fallacies by independent reviewers. Statistical analyses included chi-square tests and Fisher’s exact test for significance.ResultsChatGPT-4 answered all questions across the 10 modules, achieving an overall accuracy rate of 77.5%. The model applied logical reasoning in 98.1% of the questions, utilized internal information in 94.4%, and incorporated external information in 91.1%.ConclusionChatGPT-4 performs satisfactorily on the French Board of Plastic, Reconstructive, and Aesthetic Surgery written examination. Its accuracy met the minimum passing standards for the exam. While responses generally align with expected knowledge, careful verification remains necessary, particularly for questions involving image interpretation. As artificial intelligence continues to evolve, ChatGPT-4 is expected to become an increasingly reliable tool for medical education. At present, it remains a valuable resource for assisting plastic surgery residents in their training