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Mechanical and Thermal Contributions to the Damage Suffered by an Aeronautical Structure Subjected to an Intense and Sudden Electrical Discharge
No full textInternational audienceLightweight aeronautical structures and power generation structures such as wind turbines are fitted with protected external layers designed and certified to withstand severe climatic events such as lightning strikes. During these events, high currents flow through the structural protection but are likely to induce effects deeper in the supporting composite material and could even reach or perforate pressurized tanks. In situ measurements are hard to achieve during current delivery due to the severe electromagnetic conditions, and the lightning strike phenomenon on these structures is not yet fully investigated. To gain a better understanding of the physics involved, similarities in direct damage between lightning-struck samples and those subjected to pulsed lasers and an electron gun are analyzed. These analyses show the inability of a pure mechanical contribution to fully reproduce the shape of the delamination distribution of lightning strikes. Conversely, the similarities in effect and damage with the thermomechanical contribution of electron beam deposition are highlighted, particularly the increase in core delamination due to the paint and the apparent similarities in delamination distribution
Les arrêtés-interpellation des maires costarmoricains contre la désertification médicale suspendus pour incompétence
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From single to multi-stage forming process of copper thin sheet
No full textInternational audienceIn the electronics industry sector, different types of parts made out of copper alloys are used, such as metal supports (lead frames), on which the chips are assembled. These parts are produced using progressive dies, with several blanking and bending stages. There is a huge interest to numerically predict these multistage forming processes, to decrease design time and to anticipate production problems such as non-compliance with dimensional tolerances depending on the material used. This paper deals with the progressive forming of copper parts with single and multi-stage process coupled with experimental and numerical approaches for bending operations. The main contribution of this study is the design of a single stage bending tool for rectangular samples representative of multi-stage industrial processes, providing a relevant experimental database for numerical model validation. This device is based on the technology of progressive dies, though it allows the production of one part at a time. Instrumentation provides local load and displacement and an experimental database is built for Cu-ETP R290 copper strip. A multi-stage bending industrial process dedicated to the manufacturing of electrical contacts is also considered in this study. Numerical models of both single and multi-stage processes are developed, with a focus on the technological importance of a cam slider for the industrial process. The results show that the bending force is mainly influenced by the sample width. In addition, numerical models for the rectangular geometries capture some of the trends from the experiment such as the proportionality of the maximum force with the bent width. Overall, the models are able to predict springback within the process tolerance. Finally, comparison of one stage of the bending sequence with the single stage bending model showed that the single model approach gives similar results in terms of load and plastic deformation.</div
Digitally-assisted structure design of a large-size proton exchange membrane fuel cell
No full textInternational audienceA digitally-assisted method is proposed to accelerate the structure design of large-size proton exchange membrane fuel cells, including backward engineering and forward design
Evaluation of serum mid-infrared spectroscopy as new prognostic marker for first-line bevacizumab-based chemotherapy in metastatic colorectal cancer
No full textInternational audienceBackground and aims: Bevacizumab-based chemotherapy is a recommended first-line treatment for metastatic colorectal cancer (mCRC). Robust biomarkers with clinical practice applicability have not been identified for patients with this treatment. We aimed to evaluate the prognostic yield of serum midinfrared spectroscopy (MIRS) on patients receiving first-line bevacizumab-based chemotherapy for mCRC. Methods: We conducted an ancillary analysis from a multicentre prospective study (NCT00489697). All baseline serums were screened by attenuated total reflection method. Principal component analysis and unsupervised k-mean partitioning methods were performed blinded to all patients' data. Endpoints were progression-free survival (PFS) and overall survival (OS). Results: From the 108 included patients, MIRS discriminated two prognostic groups. First group patients had significantly lower body mass index ( p = 0.026) and albumin levels ( p < 0.001), and higher levels of angiogenic markers, lactate dehydrogenase and carcinoembryonic antigen ( p < 0.001). In univariate analysis, their OS and PFS were shorter with respective medians: 17.6 vs 27.9 months ( p = 0.02) and 8.7 vs 11.3 months ( p = 0.03). In multivariate analysis, PFS was significantly shorter (HR = 1.74, p = 0.025) with a similar trend for OS (HR = 1.69, p = 0.061). Conclusion: By metabolomic fingerprinting, MIRS proves to be a promising prognostic tool for patients receiving first-line bevacizumab-based chemotherapy for mCRC.</div
Le tournant humanitaire des engagements d’exilés. Cycle de mobilisation et de démobilisation des Vénézuéliens à Madrid (2014-2022)
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Surpopulation carcérale et personnes détenues de nationalité étrangère : une circulaire polémique
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RILEM TC 275-HDB: results of round-robin testing for the vapor permeability of hemp concrete
No full textInternational audienceAbstract Determining the hygrothermal properties of bio-based construction products on a material scale is a major challenge in order to highlight and guarantee their performances. These data are also essential to feed models at wall and building scales for prediction and optimization of their contribution to energy consumption and user’s comfort. Among these properties, water vapor permeability is commonly measured with the dry cup method. Despite the good repeatability and reproducibility of this test when performed in one lab, one can observe a high level of discrepancy in the literature values. To address the origin of these differences and establish recommendations for the characterization of highly hygroscopic and permeable bio-based materials, an interlaboratory test is therefore necessary. In the context of the activities of the RILEM TC 275-HDB, two interlaboratory campaigns have been launched to measure the water vapor permeability of bio-aggregate based building materials by means of cup test. The analysis of the results from six participating laboratories from different countries highlighted the main sources of discrepancy, in particular the progressive saturation of the desiccant during the experiment and the incompatibility of the “steady state” criterion and the air velocity recommended by the standard ISO 12572 in the case of highly permeable materials. Despite the many sources of uncertainties, recommendations are proposed to improve the accuracy of this measurement for permeable materials such as a continuous measurement of the vapor pressure within the air layer and the measurement of the air velocity above each cup to evaluate the local interface resistance
The Role of the Nurse Regulator in the Mobile Emergency Care Service: A Literature Review
No full textInternational audienceThis study aims to evaluate the scientific literature on the role of nurse regulators in the mobile emergency care service (SAMU). This is a qualitative study of the narrative literature review type, carried out through a search in the BVS, PubMED, and Google Scholar databases, which selected texts published between 2019 and 2024. The results show that nurse regulators perform functions in SAMU such as receiving and evaluating emergency calls, performing triage and risk classification of cases, in order to direct care appropriately; providing pre-hospital guidance to callers; recording and documenting all care information, contributing to the continuity of care and the assessment of the quality of the service provided, in addition to the need for effective communication and decision-making skills. These skills include technical knowledge and resource management. They must have a solid knowledge of SAMU protocols and guidelines, given that they need to quickly analyze the available information and direct the team accurately and efficiently. It is concluded that the nurse regulator is essential in the SAMU triage and regulation system, ensuring that medical care is directed efficiently and effectively. The complexity of their functions reflects the importance of robust and continuous training, aimed at improving technical skills and rapid decision-making. However, they face significant challenges such as work overload, which requires resilience and adequate organizational support to sustain the quality of care amid high demand