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Fabrication of versatile hydrogels in a facile and effective manner represents a pivotal challenge in the field of biomaterials. Herein, a novel strategy is presented for preparing on‐demand degradable hydrogels with multilevel responsiveness. By employing selenol‐dichlorotetrazine nucleophilic aromatic substitution (SNAr) to synthesize hydrogels under mild conditions in a buffer solution, the necessity of additives or posttreatments can be obviated. The nucleophilic and redox reactions between selenol and tetrazine culminate in the formation of three degradable chemical bonds—diselenide, aryl selenide, and dearomatized selenide—in a single, expeditious step. The resultant hydrogel manifests exceptional adaptability to intricate environments in conjunction with self‐healing and on‐demand degradation properties. Furthermore, the resulting material demonstrated light‐triggered antibacterial activity. Animal studies further underscore the potential of integrating metformin into Se‐Tz hydrogels under green light irradiation, as it effectively stimulates angiogenesis and collagen deposition, thereby fostering efficient wound healing. In comparison to previously documented hydrogels, Se‐Tz hydrogels exhibit controlled degradation and drug release, outstanding antibacterial activity, mechanical robustness, and bioactivity, all without the need for costly and intricate preparation procedures. These findings underscore Se‐Tz hydrogels as a safe and effective therapeutic option for diabetic wound dressings. [ABSTRACT FROM AUTHOR]

As a unique form of abiotic stress, the environmental conditions of outer space are expected to induce changes in plant genomes, proteomes and metabolic pathways. However, the effect of outer space conditions on the overall physiology of plants at the protein level has yet to be reported. To investigate the effects of outer space conditions on the growth- and development-related physiological processes and metabolic pathways of rice different stages, the seeds of rice variety DN423 were sent into orbit for 12.5 d aboard the SJ-10 Returning Satellite, and then the seedlings of both treated and control rice were compared at the three-leaf stage (TLS) and tillering stage (TS). In addition to comparing plant growth and reactive oxygen species (ROS) levels, seedling proteomes were also compared using isobaric tags for relative and absolute quantitation (iTRAQ). Space flight increased TLS plant height by 20%, reduced and increased ROS levels of the TLS and TS seedlings, respectively, and affected the expression of 36 and 323 proteins in TLS and TS leaves, respectively. Furthermore, the functions of the differentially abundant proteins were mainly associated with metabolism, energy, and protein synthesis and degradation. These results suggested that the exposure of seeds to outer space conditions affects the subsequent abundance of key signaling proteins, gene expression, and the processes of protein synthesis and degradation, thereby affecting metabolic processes and promoting adaptation to the abiotic stress of outer space. As such, the present study sheds light on the effects of space flight on plants and contributes to a more comprehensive understanding of extraterrestrial biology.

Micro-motion is a crucial feature used in ballistic target recognition. To address the problem that single-view observations cannot extract true micro-motion parameters, we propose a novel algorithm based on the narrowband radar network to extract three-dimensional precession features. First, we construct a precession model of the cone-shaped target, and as a precondition, we consider the invisible problem of scattering centers. We then analyze in detail the micro-Doppler modulation trait caused by the precession. Then, we match each scattering center in different perspectives based on the ratio of the top scattering center’s micro-Doppler frequency modulation coefficient and extract the 3D coning vector of the target by establishing associated multi-aspect equation systems. In addition, we estimate feature parameters by utilizing the correlation of the micro-Doppler frequency modulation coefficient of the three scattering centers combined with the frequency compensation method. We then calculate the coordinates of the conical point in each moment and reconstruct the 3D spatial portion. Finally, we provide simulation results to validate the proposed algorithm.