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After optimizing the original aptamer sequence by truncation strategy, a magnetic separation-assisted DNAzyme-driven 3D DNA walker fluorescent aptasensor was developed for detecting the food-borne pathogen Cronobacter species. Iron oxide magnetic nanoparticles (MNPs) modified with a hybrid of truncated aptamer probe and DNAzyme strand (AP-E1) denoted as MNPs@AP-E1, were employed as capture probes. Simultaneously, a DNAzyme-driven 3D-DNA walker was utilized as the signal amplification element. The substrate strand (Sub) was conjugated with the gold nanoparticles (AuNPs), resulting in the formation of AuNPs@Sub, which served as a 3D walking track. In the presence of the target bacteria and Mg2+, E1-DNAzyme was activated and moved along AuNPs@Sub, continuously releasing the signal probe. Under optimized conditions, a strong linear correlation was observed for Cronobacter sakazakii (C. sakazakii) in the concentration range 101 to 106 CFU mL−1, with a low detection limit of 2 CFU mL−1. The fluorescence signal responses for different Cronobacter species exhibited insignificant differences, with a relative standard deviation of 3.6%. Moreover, the aptasensor was successfully applied to determine C. sakazakii in real samples with recoveries of 92.86%—108.33%. Therefore, the novel method could be a good candidate for ultra-sensitive and selective detection of Cronobacter species without complex manipulation. [ABSTRACT FROM AUTHOR]

10 1 ¯ 1}− {10 1 ¯ 2} double twinning is a classical twinning mode with diverse variants in magnesium and its alloys. However, its variant selection criterion and its influence on the mechanical behaviors are still in debate. In this study, we proposed a view of micro-texture entropy to elucidate the double twinning behavior during large strain rolling of Mg–1.5Gd (wt%) alloy. Combined with the high spatial resolution scanning electron microscopy-transmission Kikuchi diffraction (SEM-TKD) technique, the detailed microstructure and micro-texture of the double twins in early stage of evolution were detected, and new insight into the variant selection and evolution of double twins was obtained. The observations suggest that the nucleation events of different double twin variants are influenced by their micro-texture entropy, the variants with lower micro-texture entropy are preferred. While the growth stage of double twins is affected both by their micro-texture entropy and the geometric factors between the primary and secondary twin systems; the former will influence their growth potential and the later can affect their growth space. A novel {10 1 ¯ 1}− {10 1 ¯ 3} double twin was also triggered to release the high local stress concentration during large strain rolling process. • The view of micro-texture entropy was proposed to elucidate the {10 1 ¯ 1}− {10 1 ¯ 2} double twinning behavior of Mg–1.5Gd (wt%) alloy. • For variant selection and evolution of {10-11}-{10-12} double twins, variants with lower micro-texture entropy are preferred. • Geometric factor between primary and secondary twins restricts growth space of B and C double twins to one-dimensional space. • A novel {10 1 ¯ 1}− {10 1 ¯ 3} double twin was observed because of the high local stress concentration. [ABSTRACT FROM AUTHOR]