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This paper highlights the role of 6-DOF hybrid testing as a validation tool for assessing the effectiveness of Fiber Reinforced Polymer (FRP) composite repair and retrofitting techniques in structures undergoing seismic events. By combining physical testing and numerical simulations, the advanced hybrid testing technique accurately replicates complex loading conditions, including axial, lateral, longitudinal, pitch, roll, and yaw forces. This comprehensive evaluation helps optimize the design and implementation of FRP solutions, enhancing the seismic resilience of reinforced-concrete structures. The paper presents some examples emphasizing the importance of hybrid testing in promoting the adoption of FRP composites and advancing seismic retrofitting practices in civil engineering., KEYNOTE: 2023 IIFC Medal Recipient - Professor Riadh Al-Mahaidi

We report the synthesis of a new non-enzymatic H2O2 electrochemical sensor based on the Bi2S3/g-C3N4 core-shell nanocomposite. The Bi2S3/g-C3N4 nanocomposite was synthesized via the solvothermal process. It was characterized by XRD and TEM to identify its phase and to determine its morphology. The response of Bi2S3/g-C3N4 nanocomposite to hydrogen peroxide was investigated using the cyclic voltammetry and amperometry techniques. The obtained results show that the association of g-C3N4 nanosheets with Bi2S3 nanorods enhances the electrochemical behavior and the overall performance of the sensor. Indeed, we noted an enhanced electrochemical signal of the Bi2S3/g-C3N4 core-shell nanocomposite shown by the appearance of a H2O2 oxidation peak at around 0.26 V. Moreover, the modified Bi2S3/g-C3N4 electrode sensor demonstrated a wide linear range for H2O2 from 0.5 to 950 μM with a sensitivity of 1011 μA mM-1cm-2 and a detection limit of 78 nM. These performances are much better than those for Bi2S3 and g-C3N4 taken separately. The improved electrocatalytic activity of the sensor towards hydrogen peroxide oxidation is mainly attributed to the morphology of the core-shell nanostructure leading to the enrichment of electroactive sites for the catalytic reaction of H2O2. Additionally, the proposed sensor was successfully tested in skimmed milk and human urine samples. The novelty of this work is the simple way to synthesis Bi2S3/g-C3N4 core-shell nanostructure and its use as a H2O2 sensor, which paves the way for the synthesis of new nanomaterial heterostructures used as electrochemical sensors for detecting other molecules.

International audience; The choice of the functional monomer is addressed in the present study. It is not only dictated by its ability to interact with the template molecule. Its reactivity towards the cross-linker in the radical polymerization reaction is also to be considered in order to yield a suitable distribution of the monomer bearing binding groups within the material and also to adjust the cross-linking degree which provides rigidity to MIP network. MIPs prepared using two functional monomers of very different reactivity in radical polymerization allowed to investigate the criteria for the optimum choice of the functional monomer. MIPs were made of cross-linked poly(methacrylic acid) or poly(maleic acid) bound as thin films to a silica solid support. Ethylene glycol dimethacrylate was the cross-linker. Calculations of the composition drift of the copolymer material from monomers reactivity ratios give new insights into the control of MIP properties by the choice of the functional monomer. As a consequence of the lower reactivity of maleic acid than methacrylic acid for copolymerization with methacrylic esters, the incorporation of maleic acid is low, the cross-linking density is very high, the polymer coating is very thin, and the specific area is high. The final structure of the MIP network with a predominance of isolated functional units closely surrounded by cross-links yields a rigid material capable of preserving the memory of the model molecule of patulin in molecular imprints. Low reactivity of the functional monomer has beneficial effects regarding the binding selectivity for the target molecule compared to materials prepared from the more reactive methacrylic acid which lead to the formation of flexible polymer formed of short poly(methacrylic acid) sequences.

Extracranial carotid artery aneurysms in children are extremely rare, nevertheless associated with a great potential of thromboembolic episodes and rupture especially those with mycotic origin. The surgical treatment is very challenging, and there is still a controversy concerning revascularisation after the resection of the aneurysm. In this manuscript, we report the observation of an 8-year-old boy with the medical history of Leukemia who is admitted urgently for a mycotic right common carotid artery aneurysm, occurring after a chemoport infection who was operated on in our cardiovascular surgery department with surgical resection and ligation. It is the second report in the pediatric literature of a mycotic pseudoaneurysm situated in the common carotid artery, but the first documented by medical imagery. Through this case, we highlight that ligation of the infected carotid artery can be a safe and efficient alternative especially in Children.

This paper evaluates the behaviour of reinforced concrete (RC) slabs strengthened in shear with prefabricated L-shaped carbon fibre–reinforced polymer (CFRP) laminates. Four large scale slabs were tested; one slab was kept without strengthening and the other three slabs were strengthened with L-CFRP laminates using different configurations. The behaviour of the slabs strengthened with L-CFRP laminates was compared with that of a similar slab without shear reinforcement. The details of the strengthening methods implemented in the study, experimental setup and parameters of all the material used are provided. The experimental results are presented including deflection, strain readings and rotation as well as the crack pattern of each specimen. The test results reveal that using post installed L-CFRP laminates can significantly improve the punching shear capacity and deformation capacity of RC slabs. Further, the strengthening technique can also be used to prevent sudden collapse of buildings after punching shear failure by increasing the post punching deformation of slabs. The experimental results were compared with the theoretical results predicted by ACI 318 (2011), Eurocode 2 (2004) and Fib Model Code (2010).

While sustainability addresses the economic, social and environmental impacts distributed over the life cycle of a structure; commonly, ordinary events such as construction, normal operation and ageing are considered and the resilience of the structure to extreme events (natural disasters and man-made hazards) is often ignored. This study aims to introduce a framework to systematically integrate seismic-resilience into sustainability assessment of structures/infrastructures. A case study of a multi-story limited-ductility reinforced-concrete (RC) building with soft-story collapse mechanism is presented. This mode of failure is often expected in regions of low to moderate seismicity, where the detailing is poor. A numerical model is constructed based on the results of a number of multi-axis hybrid simulations allowing to realistically capture the three-dimensional response and the damage states of the RC building first-story columns from linear-elastic range to collapse. In addition, the application of carbon-fiber reinforced polymers (CFRP) as a cost-effective and rapid repair strategy in restoring the building columns is studied. The CFRP repair is proposed as an alternative to the demolition of the full building when subjected to large deformations; thereby, significantly enhancing post-disaster reparability and resilience of the structure. The developed numerical models are then used to quantify the sustainability metrics including repair cost, repair downtime and repair environmental impacts. These metrics are quantified by consecutive hazard, structural response, damage state, and recovery loss analyses in accordance to the PEER PBEE methodology. The results are then used to quantify the resilience parameters, including loss of performance and recovery, using the probabilistic resilience-based earthquake engineering (RBEE) approach.

The effectiveness of using FRP materials to strengthen existing concrete structures is hampered by the weak bond properties between the FRP and the concrete. Further, very few studies are available on the fatigue performance of FRP-strengthened reinforced concrete beams in bridges. Investigation of the fatigue performance of FRP bonded to concrete is important due to the fact that bridges are subjected to very high levels of cyclic loading throughout their lifetime. This paper focuses on a numerical and experimental investigation of the fatigue life of FRP laminates bonded to concrete. FRP-to-concrete joints were subjected to cyclic loading at various stress ratios and the number of cycles prior to failure was used to generate S-N curves which relate the stress ratio to the number of cycles. Further, numerical simulations using the finite element method were performed using a concrete material model capable of sustaining fatigue damage. The finite element results were found to be in good agreement with the experimental data and were used to provide further insights into the mechanisms of fatigue damage. Both the experimental and numerical results showed that no fatigue degradation occurred when the maximum stress ratio was less than 75% of the ultimate static capacity.

Mycotic aneurysm, which complicates 2.5%–10% of cases of infectious endocarditis, is an important cause of morbidity and mortality despite antibiotic therapy. Elective surgery remains the cornerstone of the treatment of mycotic aneurysms because of the major risk of rupture. For femoral arteries, the surgical treatment is based on the resection of the aneurysm, with revascularization of the territory downstream. The recommended materials for revascularizations are in the first place biological grafts such as veins grafts (great saphenous vein) and homograft. In our observation, faced with the small diameter of the internal saphenous vein and the lack of homograft availability, and considering the high risk of infection recurrence at the operating site, we opted for the confection of biological graft using bovine pericardium and we think that it will be more resistant to infection than prostheses. According to our knowledge, this technique has not been reported before in the literature, and the validation of this technique on a series of cases and in the long term is necessary.

Funding Acknowledgements Type of funding sources: None. Background : Despite the progress in therapy and patient management in cardiac surgery, postoperative mediastinitis remains serious complication. Our study aims to study the incidence of mediastinitis after cardiac surgery and to identify the risk factors. Methods We conducted a retrospective, descriptive study including patients who had undergone cardiac surgery by sternotomy during a period of 5 years ( 2015 – 2019)and who meet the definition of mediastinitis proposed by the "Centers of disease control and disease". We collected the demographic characteristics of the patients and operative operative data of the first intervention as well as those relating to mediastinitis. Results 25 patients ( 2.93%) among 1042 patients operated for cardiac surgery during the cited period presented mediastinitis. The main clinical signs were : surgical wound infection (80%), fever (40%) and sternal instability (30%). Biological tests showed : hyperleukocytosis and high C-Reactive Protein in 22.7 % and 58.1 % of cases respectively. Gram-positive cocci are largely predominant and one case of Candida mediastinitis was found. type 1 diabetes and coronary artery bypass grafting were significantly associated with the occurrence of mediastinitis with P 92 % of patients operated on for mediastinitis are cured, 4 % had a recurrence of infection and 4 % died. CONCLUSION Mediastinitis after heart surgery is rare but serious. The main risk factors are insulin-dependent diabetes and coronary bypass surgery. The curative treatment is heavy and it is based on a rigorous and long medico-surgical care.