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Abstract Background Transient and stable gene transformation systems play a crucial role in elucidating gene functions and driving genetic improvement in plants. However, their application in medicinal woody plants has been hampered by inefficient procedures for isolating protoplasts and regenerating plants in vitro. Results Embryogenic callus protoplast isolation and transient transformation system were successfully established. The highest yield of protoplasts was approximately 1.88 × 106 cells per gram with a viability of 90% under the combination of 1.5% cellulase and 0.2% macerozyme, with enzymatic digestion for 6 h in darkness followed by centrifugation at 400×g for 5 min. The transient transfection rate of protoplast reached 45.56% at a PEG 4000 concentration of 40%, a transfection time of 40 min, 16 h of dark incubation, a plasmid concentration of 1.5 ng μL−1, and 25 min heat shock at 45 °C. In addition, 15 Agrobacterium tumefaciens-mediated GUS-positive seedlings were obtained through the somatic embryogenetic pathway under the optimized conditions. Conclusion This study successfully established both transient and stable genetic transformation systems, paving the way for future molecular biology research on A. senticosus. Graphical Abstract

A powder metallurgy superalloy prepared by hot pressing (HP) was forged under static and oscillatory pressures. The microstructure, mechanical properties and fracture behavior of the sample before and after forging were characterized in detail. The results showed that the forging processes could effectively break the prior particle boundaries (PPBs) and reduce the PPBs precipitates, thus significantly improved the mechanical properties of the material. In particular, the hot oscillatory forging (HOF) process increased the tensile elongation and stress rapture life of the hot forged sample by 1.3 and 3.5 times, respectively. The present study suggests that HOF could be a promising technique for preparing high-performance superalloys.