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Background: radiation-induced skin injury (RISI) is a common complication of radiotherapy, affecting 85–95% of patients. Current treatments lack sufficient evidence of efficacy. Acellular dermal matrix (ADM) hydrogels have shown promise in treating chronic wounds, burns, and ulcers, but their potential in RISI remains unexplored. Methods: ADM hydrogels were prepared from porcine dermis and characterized using histological staining, scanning electron microscopy (SEM), and rheological assessments. A rat model of RISI was established, and the therapeutic effects of the ADM hydrogel were evaluated by gross observation, histological analysis, and immunofluorescence staining. Oxidative stress, angiogenesis, apoptosis, macrophage infiltration, and inflammatory responses were also assessed. Results: ADM hydrogel treatment significantly reduced wound area, radiation injury scores, and apoptosis while increasing epithelial thickness and hair follicle regeneration compared to the control group. The hydrogel promoted angiogenesis, vascular maturation, and M2 macrophage polarization. It also decreased the expression of pro-inflammatory cytokines (IL-1β and IL-6) and increased the expression of the anti-inflammatory cytokine IL-10. No significant differences in antioxidant effects were observed between the groups. Conclusion: The ADM hydrogel effectively promotes the healing of RISI in a rat model by modulating the inflammatory microenvironment and enhancing angiogenesis. These findings suggest that the ADM hydrogel could serve as a promising novel biomaterial for the management of RISI. [ABSTRACT FROM AUTHOR]

User pairing plays an important role in device‐to‐device (D2D) relay communication, contributing significantly to maintaining low energy consumption, high throughput, and overall energy efficiency in the communication system. To achieve these purposes, an attention‐based long short‐term memory motion prediction model (AT‐LSTM) and propose a joint power control algorithm. Leveraging these techniques, we also propose a D2D user pairing algorithm, distance–power–SINR pairing algorithm (DPSPA), which comprehensively considers factors such as D2D communication distances, transmit power, and signal‐to‐interference‐plus‐noise ratio. Initially, the AT‐LSTM model is utilized to predict the location of users. Subsequently, the distance between the user terminal device and each communication point and the base station, filtering cache points, and non‐cache points within the D2D communication radius are calculated. Then, based on the distance, required transmission power, and signal‐to‐interference‐plus‐noise ratio of each point, the evaluation index (the best matching product) is obtained. Finally, the point with the maximum best matching product is selected for D2D direct communication mode, D2D relay communication mode, or cellular communication mode. Simulation results demonstrate that DPSPA effectively reduces system energy consumption, enhances system throughput, and improves overall energy efficiency. [ABSTRACT FROM AUTHOR]

Performance analysis of linear induction motor on medium and low speed maglev train is difficult because of its asymmetric magnetic circuit, longitudinal edge end effect and lateral side end effect. In this paper, traction force and normal force of linear induction motor of medium-low speed maglev train are calculated by magnetic circuit method, two-dimensional finite element method and three-dimensional finite element method respectively. Based on a full model three-dimensional finite element simulation, a periodic semi model finite element simulation is proposed, and a static test platform of medium and low speed maglev linear motor is built. Test results show that the deviation of traction force between periodic semi-model finite simulation results and test results is 3.9%, which is consistent with the full model finite element simulations results. Using the periodic half model method, the simulation time can be reduced by 40%, which not only gives consideration to derivation accuracy, but also increases calculation speed. Based on this method, the maximum accuracy of calculation can be achieved in design stage, and the design risk caused by the failure of dynamic performance test of linear induction motor can be reduced.

Mortality rate in older adults following extensive burn injury is extremely high, and management of these patients is challenging. One of the main problems is that autologous split-thickness skin grafts are scarce and the wounds cannot be covered quickly and effectively. Intermingled skin grafting is a low-tech and economic method, which not only maximizes the use of precious autologous skin but also prevents the wounds from infection and consumption. Herein we present a case of extensive burn injury in a 68-year-old female successfully treated with intermingled skin grafting. The patient was accidentally burned by gas flame, resulting in a major burn injury covering 80% of her total body surface area. Early burn wound excision was performed and the wound was temporarily covered with irradiated porcine skin in the first week after injury. Autologous stamp-like skin grafts were applied to the wound bed 4 weeks after injury. In this operation, the results were not satisfactory. The take rate of the skin grafts is only about 50%. We covered the wounds with intermingled skin allografts and autografts 8 weeks after injury: autografts (0.5 cm × 0.5 cm) + fresh close relative’s allografts (1 cm × 1 cm) + cryopreserved allografts (2 cm × 2 cm).

The complex structure of Ti/HA (HA: hydroxyapatite) implants prepared by additive manufacturing technology plays an essential role in its application in bone repair. Digital light processing (DLP) is widely used to prepare bioceramics with complex structures. However, it is a challenge to prepare Ti/HA biomaterials by DLP due to the high ultraviolet (UV) absorption of Ti powder. In the present work, TiH2 powder coated with a TiO2 layer is selected to reduce the UV absorption and improve the curing depth for DLP printed green bodies of TiO2@TiH2/HA, because the TiO2@TiH2 powder can be reduced by 12.7% compared to the TiH2 powder without any oxidation. Then, the shell layer of TiO2 undergoes dehydrogenation and reduction reaction with the core phase of TiH2 during the sintering process to transfer TiO2@TiH2/HA into TixOy@Ti/HA. In addition, the effects of HA content on compressive strength and biocompatibility are investigated in the TixOy@Ti/HA biomaterials. The results show that when adding 60 vol%HA, the maximum monolayer curing depth of the slurry reaches 90.1 ± 3.5 µm. 40%TixOy@Ti/60%HA shows the maximum effect in promoting the pre‐osteoblast differentiation and a relatively high compressive strength of 48.7 ± 3.5 MPa. This work provides an experimental basis for the preparation of ceramic–metal composites with high UV absorptivity using DLP. [ABSTRACT FROM AUTHOR]