Use of Distributed Optical Fibre to Monitor the Crack Propagation of an Adhesively Bonded Joint During an ENF Test

International audienceThe floating production, storage and offloading units (FPSO) being generally in a tropical area, makes corrosion a fundamental ageing problem of these steel structures. Therefore, there is a strong need for proposing repair solutions having low impact on their exploitation. The owner of these units are highly interested in the development of "cold repair" in contrast with "hot works" which require to stop the production for security risks, like adhesively bonded FRP (Fibre Reinforced Polymer) patch which requires additional development, in particular in the design step. The design of these reinforcements needs a complete understanding of the mechanical state of the patch which is based on the different materials and interfaces properties. Fracture mechanics seems an interesting option to express the mechanical state of the patch and more particularly the risk to undergo interlaminar fracture or steel interface debonding failure before materials failure. The experimental definition of the required design values for such an approach (critical toughnesses) are generally obtained with common tests such as DCB or ENF tests. The presented study is focused on the determination of the critical toughness in mode II through ENF (End Notched Flexure) test which can be done following some standards, such as ASTM D7905. A distributed optical fibre was used to verify the correct determination of the initial crack length, to determine the crack propagation during the test, and to monitor the fracture process zone length. The currently used methods, such as visual observation or Digital Image Correlation (DIC) of the crack front at the border of the sample, may indeed induce error if the crack is not straight. To compare these methods, the realized test was monitored using a distributed optical fibre placed in the centre of the lap width, in and on the specimen. Firstly, the issues related to the integration of this continuous optical fibre will be raised (insertion, precision resolution, measurement noise). Then, some experimental investigations will be described presenting different monitoring strategies using continuous optical fibre measurement and Digital Image Correlation technique (DIC). The obtained results will be analyzed focusing on the proper determination of the critical toughness of the adhesive. This will then be used to design and optimize the monitoring strategy of a wider experimental campaign

Predictive value of FDG PET-CT in adult with T lymphoblastic lymphoma

International audienc

Place de la chimiothérapie dans la leucémie lymphoïde chronique

Place de la chimiothérapie dans la leucémie lymphoïde chroniqu

Relevance of Damped Harmonic Oscillation for Modeling the Training Effects on Daily Physical Performance Capacity in Team Sport

International audienceContext: Positive and negative effects of training induce apparent oscillations of performance, suggesting that the delayed cumulative effects of training on daily performance capacity (DPC) are best fitted by sine waves damped over time. Purpose: To compare the criterion validity of the impulse-response (IR) model of Banister et al and the damped harmonic oscillation (DHO) model for quantifying the training load (TL) DPC relationship. Methods: Six female professional volleyball players (20.8 +/- 2.4 y) were monitored using the session rating of perceived exertion (sRPE) for 9 mo to quantify TL. Countermovement-jump (CMJ) and 4-step-approach-CMJ (4sCMJ) performances were recorded once a month. Parameters of models were determined by minimizing residual-sum squares between predicted and real performances with a nonlinear regression. Results: DPC was best fitted by the DHO model rather than the IR model (CMJ, R-2 =.80 +/-.08 and.69 +/-.20, respectively; 4sCMJ, R-2 = .86 +/- .09 and .67 +/-.29, respectively). The damping parameter theta and the period T were positively correlated with age (rho = 0.81, P <.05, and rho = 0.86, P <.02, respectively). Conclusions: The DHO model is a useful tool for modeling DPC as the sum of the delayed DPCs from the consecutive training and recovery days. DPC could be considered the expression of the individual process of accumulation and dissipation of fatigue induced by training. DHO-model parameters were correlated with age, which prompts one to postulate that expertise has a major influence on DPC. The DHO model will help coaches develop a greater understanding of training effects and make monitoring of the training process more effective

Adult T-type lymphoblastic lymphoma: treatment advances and prognostic indicators.

T-cell lymphoblastic lymphoma (T-LBL) is a rare, aggressive neoplasm of precursor T cells that occurs mostly in adolescents and young adults. In this review, we describe the treatment of adult T-LBL with a focus on recent advances using pediatric-inspired acute lymphoblastic leukemia regimens, which have greatly improved outcome. We also discuss the development of prognostic indicators for T-LBL, especially oncogenetic factors, that can identify patients at higher risk of relapse and should help further extend T-LBL patient survival. Pediatric-inspired acute lymphoblastic leukemia regimens have the potential to become the treatment of choice for adult T-LBL, and their use might also reduce the need for other long-standing T-LBL interventions, particularly mediastinal irradiation and stem cell transplantation

Fatal Invasive Trichosporonosis Caused by Trichosporon inkin after Allogeneic Stem Cell Transplant for very Severe Idiopathic Aplastic Anemia

International audienceInvasive Trichosporon inkin fungal infections are rare and unusual, occurring nearly exclusively in immunocompromised patients experiencing prolonged neutropenia during treatment of malignant hemopathies or other immunodeficiency conditions. We report a case of a 27-year-old patient with severe aplastic anemia who developed Trichosporon inkin sepsis with skin lesions during aplasia after myeloablative allogeneic stem cell transplant. He was treated with liposomal amphotericin B but died from multiple organ failure. We then discuss the epidemiological, clinical and therapeutic features of these serious fungal infections compared to the published data

Development of Composite patch for Offshore Steel Repair

International audienceThe number of floating production, storage and offloading units (FPSO) around the globe is in continuous increase and a relatively high number of them are now almost 20 years aged. The general geographical layout, being in tropical area makes the corrosion a fundamental ageing problem of the steel structures in structural area, like decks or side shell but also inner structure. Therefore, there is a strong need for proposing repair solutions having low impact on their exploitation. Such repair solutions (“cold repair” in contrast with “hot works”), like adhesively bonded FRP (Fiber Reinforced Polymer) requires additional development, in particular in the preliminary characterization and design step, and regarding the durability issues. Use of composite to build onsite repair seems adequate to solve this issue as they require limited heat (80°C) and can easily be installed on various shape, position and surfaces. However, the lack of application cases and design method lead to limited references on the best way to install composite patch repair. By design, the stress concentration at the border of the patch tends to decrease the overall strength and failure load that adhesives can sustain. Therefore, patch geometry must be addressed with care to obtain high performance patches. The overall capacity of the patch is highly related to the energy that can withstand the bonded interface with the steel adherent, and so, a particular attention to the surface preparation must be taken. Finally, the patch layup controls the overall stiffness and strains in the patch, which must lead to a particulardesign to obtain the required properties.This paper presents the design methodology, the surface preparation protocol study and the manufacturing protocol of a composite patch developed during the Joint Industrial Project Strength Bond Offshore. The results of the static and fatigue test campaign in tension and bending are also presented. The assessment of the overall capacities of the composite patch repair are compared to a simpler bonded steel repair. The use of distributed strain measurement optical fiber as the new patch monitoring technique applied to composite patch are developed and highlighted

A new adhesively bonded composite repair for offshore steel structures: strength assessment and fatigue

International audienceFloating productions, storage and offloading (FPSO) units are subject to corrosion problems. The use of adhesively bonded FRP patches as a repair appears to be a particularly interesting solution. However, design strategies still need to be improved and validated to insure the robustness and, ultimately, confidence in this solution. Since 2018, Bureau Veritas leads a joint industrial project called Strength Bond Offshore which aims at defining such a design strategy. First, the patch designed during this project will be presented. Then, the experimental test campaign is detailed: manufacturing, monotonic tests in traction and bending. Finally, the results of the fatigue tests campaign are developed. Ongoing additional developments are under progress to better assess equivalent interfacial behaviors for an overall design strategy

Evaluation de la résistance sous chargement monotone et vis-à-vis de la fatigue de patchs collés développés pour la réparation de structures métalliques offshore

International audienceThe number of floating productions, storage and offloading (FPSO) units in the world is constantly increasing and the problem of corrosion is an important element for these units. There is a strong need to offer repair solutions with a low impact on their operation, in particular avoiding the hot work commonly encountered in the case of conventional repairmethodologies. For these reasons, the use of adhesively bonded FRP (Fibre Reinforced Polymer) patches appears to be a particularly interesting solution. However, strong problems exist concerning the definition of design methodologies, robustness and the consideration of durability for the design of these repairs. In order to develop such a methodology,Bureau Veritas leads a joint industrial project called SBO (JIP Strength Bond Offshore) aiming at defining such a design strategy. The work presented is part of this project and consisted in applying the principles of fracture mechanics for the characterization of bonded composite-steel assemblies. First, the conclusions of the design are presented. The execution of the experimental test campaign is then detailed (manufacturing of the specimens and monotonic tests in traction andbending). Then, the results of the fatigue tests campaign are developed and compared to standards.Le nombre d’unités flottantes de production, de stockage et de déchargement (FPSO) est en augmentation continue et la problématique de la corrosion est un élément important pour ces unités. Il est nécessaire de proposer des solutions de réparation ayant un faible impact sur leur exploitation, évitant notamment les travaux à chaud. Pour ces raisons, l'utilisation de patchs en PRF (Polymère Renforcé de Fibres) collés apparaît comme une solution particulièrement intéressante. Cependant, de fortes problématiques existent concernant la définition de méthodologies de conception, la robustesse et la prise en compte de la durabilité pour la conception de ces réparations. Afin de développer une telle méthodologie, Bureau Veritas pilote un projet industriel conjoint appelé SBO (JIP Strength Bond Offshore) visant à définir une telle stratégie de conception. Le travail présente une partie des résultats obtenus via une application des principes de la mécanique de la rupture pour la caractérisation de la résistance d’assemblages collés composite-acier. Premièrement, les conclusions du dimensionnement sont présentées. La réalisation de la campagne d’essai expérimentale est ensuite détaillée (fabrication des éprouvettes, et réalisation des essais monotones en traction et flexion). Enfin, les résultats de la campagne d’essais de fatigue sont développés et comparés aux références normatives