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Fault fracture zones are rock formations commonly encountered in submarine tunnels, and the diffusion mechanism of slurry in fault fracture zones has a crucial impact on submarine tunnel reinforcement. Based on the seepage equation of Bingham fluid, the tortuosity parameter, fractal theory, and variable viscosity equation are introduced to establish a spherical permeation grouting model of Bingham fluid considering the slurry diffusion path and viscosity time variability. The viscosity variation law with time of sulfur aluminate cement slurry under different seawater admixture conditions was tested, and the time-varying equation of viscosity of sulfur aluminate cement slurry was obtained by fitting. A set of fault fracture zone permeation grouting test system was developed, and a fault fracture zone grouting simulation test was carried out. The study shows that the diffusion distance calculated without considering the influence of slurry diffusion path and seawater is 1.63–1.91 times of the test value, which obviously overestimates the diffusion distance; the diffusion distance calculated with considering the influence of diffusion path and seawater is 1.06–1.35 times of the test value, which is in good agreement with the test value. The research results can provide some theoretical support for the design of grouting in seawater environment. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the role of a novel total meniscal implant in promoting meniscal regeneration and protecting articular cartilage in a rabbit model for 3 and 6 months. Methods: Thirty‐six New Zealand rabbits were selected and divided into poly(ɛ‐caprolactone) (PG‐Pg) scaffold group, meniscectomy group and sham group. In this study, it was investigated whether PG‐Pg scaffold can prevent articular cartilage degeneration and promote tissue degeneration, and its mechanical properties at 3 and 6 months after surgery were also explored. Result: The degree of articular cartilage degeneration was significantly lower in the PG‐Pg scaffold group than in the meniscectomy group. The number of chondrocytes increased in the PG‐Pg scaffold at 3 and 6 months, while a gradual increase in the mechanical properties of the PG‐Pg stent was observed from 6 months. Conclusion: The PG‐Pg scaffold slows down the degeneration of articular cartilage, promotes tissue regeneration and improves biomechanical properties after meniscectomy. This novel meniscus scaffold holds promise for enhancing surgical strategies and delivering superior long‐term results for individuals with severe meniscus tears. Level of Evidence: NA. [ABSTRACT FROM AUTHOR]

Extracting discriminative features using vision transformer is a popular research direction for person re-identification. However, feature extraction of existing vision transformer is relatively simple. To solve this problem, we design a vision transformer with multiple granularities for person re-identification. We propose three stages of multi-granularity feature extraction, including stage1 (shuffle), stage2 (split and concat) and stage3 (refine and enhance), which help the model to extract local and global fine features in strips. The highlight block is added in stage3 to enhance features by mathematical variation, which will highlight and strengthen the core features that are beneficial to classification. In addition, the loss function is optimized by introducing Circle Loss on top of ID Loss and Triplet Loss, and using the weighted sum of the three as the final loss function. Finally, we evaluated the performance of our method on three standard benchmark datasets: Market-1501, DukeMTMC-reID and MSMT17, and experimental results show that our method is superior to the state-of-the-art methods. [ABSTRACT FROM AUTHOR]