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In this work, a desirable combination of mechanical properties is achieved at 550 °C by tailoring the boundary microstructure between the primary α phase (αp) and the transformed β structure (βtrans) in a dual-phase Ti-6242s titanium alloy. The αp/βtransboundary is displaced by a transition region that consists of β nano-plates or nanoprecipitates gradually penetrating into the αpin a particular semi-equiaxed microstructure (S-ES). The results show that the αp/βtransboundary, where strain concentration easily occurs during deformation in the equiaxed microstructure (ES), induces recrystallization softening in the α phase. However, the transition region in the S-ES alleviates the strain localization and thus effectively inhibits the recrystallization softening that occurred in the α phase with concentrated strain. These β plates/precipitates in this region in turn enable an appropriate accumulation of dislocations. Significant improvement in the high-temperature strength, ∼240 MPa for the yield strength, is obtained for the S-ES relative to the ES. This work provides a new strategy for achieving outstanding strength at high temperature by designing special boundary architecture in dual-phase titanium alloys.

It is well known that as the power grid becomes more and more complex, the traditional manual survey of transmission towers is inefficient and cannot meet the requirements of safe and stable operation. Although the development of the satellite remote sensing technology provides a new prospect for the efficient and stable survey of transmission towers, there are still many problems that need to be solved. Due to the harsh climate and limitations of the imaging equipment, some of the transmission tower objects in the remote sensing images are blurred, which makes it extremely difficult to generate datasets and to achieve high precision transmission tower object detection. To further develop the detection precision of transmission towers, the image enhancement algorithm based on the dark channel priori is firstly applied for remote sensing images, which can boost the image interpretability. Then, considering that there are still some transmission towers in the enhanced images that cannot be manually labeled, a pseudo-label-based semi-supervised learning method is employed to maximize the use of the existing data. Based on this high-quality dataset, a satellite remote sensing object detection model for transmission towers is constructed using mobile inverted bottleneck convolution and deformable convolution. Finally, the ablation and comparative experiments are conducted according to the satellite remote sensing image dataset of a certain area in China. The experimental results indicate that both the image enhancement and the semi-supervised learning methods can improve the detection precision, and compared with the existing mainstream model, the proposed method performs better.

The restoration of bone defects caused by osteoporosis remains a challenge for surgeons. Strontium ranelate has been applied in preventative treatment approaches due to the biological functions of the trace element strontium (Sr). In this study, we aimed to fabricate bioactive scaffolds through Sr incorporation based on our previously developed modified amino-functional mesoporous bioactive glass (MBG) and to systematically investigate the bioactivity of the resulting scaffold in vitro and in vivo in an osteoporotic rat model. The results suggested that Sr-incorporated amino-functional MBG scaffolds possessed favorable biocompatibility. Moreover, with the incorporation of Sr, osteogenic and angiogenic capacities were upregulated in vitro. The in vivo results showed that the Sr-incorporated amino-functional MBG scaffolds achieved better bone regeneration and vessel formation. Furthermore, bioinformatics analysis indicated that the Sr-incorporated amino-functional MBG scaffolds could reduce reactive oxygen species levels in bone marrow mesenchymal stem cells in the osteoporotic model by activating the cAMP/PKA signaling pathway, thus playing an anti-osteoporosis role while promoting osteogenesis. This study demonstrated the feasibility of incorporating trace elements into scaffolds and provided new insights into biomaterial design for facilitating bone regeneration in the treatment of osteoporosis.

Medication-related osteonecrosis of the jaw (MRONJ) is primarily associated with administering antiresorptive or antiangiogenic drugs. Despite significant research on MRONJ, its pathogenesis and effective treatments are still not fully understood. Animal models can be used to simulate the pathophysiological features of MRONJ, serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of MRONJ. Rodent models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ, but classical methods cannot achieve a complete replica of the pathogenesis of MRONJ. Modified rodent models have been reported with improvements for better mimicking of MRONJ onset in clinic. This review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and efficiency. Currently, there is a lack of a unified assessment system for MRONJ models, which hinders a standard definition of MRONJ-like lesions in rodents. Therefore, this review comprehensively summarizes assessment systems based on published peer-review articles, including new approaches in gross observation, histological assessments, radiographic assessments, and serological assessments. This review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.