Background: Kawasaki disease (KD) is an acute and systemic vasculitis. Its complications in coronary artery aneurysms (CAA) make KD one of the leading causes of acquired cardiovascular diseases in childhood. Low density lipoprotein receptor-related protein 1B (LRP1B) is abundantly expressed in the medial layer of coronary arteries and involved in endothelium inflammations. Purpose: We aimed to identify the role of LRP1B in CAA formation during KD progression. Methods: we investigated genetic variations in LRP1B in a Taiwanese cohort of 258 KD patients (83 with CAA and 175 without CAA complications). We used univariate and multivariate regression analyses to identify the associations between LRP1B genetic variations and KD patients. Results: CAA formation in KD was significantly associated with the LRP1B (rs6707826) genetic variant (p = 0.007). By using multivariate regression analysis, significant correlations were observed between KD with CAA complications and the presence of the TT+TG genotypes for the LRP1B rs6707826 single-nucleotide polymorphism (full model: odds ratio = 2.82; 95% CI = 1.33–5.78). Conclusion: Our results suggest that genetic polymorphism of LRP1B gene may be used as a genetic marker for the diagnosis and prognosis of the CAA formation in KD and contribute to genetic profiling studies for personalized medicine.
The influence of hygrothermal aging on high-velocity impact damage of carbon fiber-reinforced polymer (CFRP) laminates is investigated. Composite laminate specimens were preconditioned in water at 70 °C. The laminates were subsequently impacted by flat-, sphere-, and cone- ended projectiles with velocities of 45, 68, and 86 m/s. The incident and residual velocities were collected during the impact test. The impact-induced damages were measured by ultrasonic C-scan, a digital microscope system, and a scanning electron microscope. The results show that the hygrothermally conditioned laminates offer a higher energy absorption during high-velocity impact. Due to the weakening of the interlaminar properties, the hygrothermally conditioned laminates are more susceptible to delamination failure, and shear-induced debonding dominates. The projected delamination area increases with the increment of impact velocity. The damaged region becomes close to a circular shape after hydrothermal conditioning, and close to a rhomboidal shape for the dry specimens.
25 February 2024 in Journal of Sound and Vibration
The mechanical properties of quasi-brittle materials, which are widely used in engineering applications, are often affected by the thermal condition of their service environment. Moreover, the materials appear brittle when subjected to tensile loading and show plastic characteristics under high pressure. These two phenomena manifest under different circumstances as completely different mechanical behaviors in the material. To accurately describe the mechanical response, the material behavior, and the failure mechanism of quasi-brittle materials with the thermo-mechanical coupling effect, the influence of the thermal condition is considered in calculating bond forces in the stretching and compression stages, based on a new bond-based Peridynamic (BB-PD) model. In this study, a novel bond-based Peridynamic, fully coupled, thermo-mechanical model is proposed for quasi-brittle materials, with a heat conduction component to account for the effect of the thermo-mechanical coupling. Numerical simulations are carried out to demonstrate the validity and capability of the proposed model. The results reveal that agreement could be found between our model and the experimental data, which show good reliability and promise in the proposed approach.