Recent studies showed that Escherichia coli (E. coli) strains isolated from captive giant pandas have serious resistance to antibiotics and carry various antibiotic resistance genes (ARGs). ARGs or virulence-associated genes (VAGs) carried by antibiotic-resistant E. coli are considered as a potential health threat to giant pandas, humans, other animals and the environment. In this study, we screened ARGs and VAGs in 84 antibiotic-resistant E. coli strains isolated from clinically healthy captive giant pandas, identified the association between ARGs and VAGs and analyzed the phylogenetic clustering of E. coli isolates. Our results showed that the most prevalent ARG in E. coli strains isolated from giant pandas is blaTEM (100.00%, 84/84), while the most prevalent VAG is fimC (91.67%, 77/84). There was a significant positive association among 30 pairs of ARGs, of which the strongest was observed for sul1/tetC (OR, 133.33). A significant positive association was demonstrated among 14 pairs of VAGs, and the strongest was observed for fyuA/iroN (OR, 294.40). A positive association was also observed among 45 pairs of ARGs and VAGs, of which the strongest was sul1/eaeA (OR, 23.06). The association of ARGs and mobile gene elements (MGEs) was further analyzed, and the strongest was found for flor and intI1 (OR, 79.86). The result of phylogenetic clustering showed that the most prevalent group was group B2 (67.86%, 57/84), followed by group A (16.67%, 14/84), group D (9.52%, 8/84) and group B1 (5.95%, 5/84). This study implied that antibiotic-resistant E. coli isolated from captive giant pandas is a reservoir of ARGs and VAGs, and significant associations exist among ARGs, VAGs and MGEs. Monitoring ARGs, VAGs and MGEs carried by E. coli from giant pandas is beneficial for controlling the development of antimicrobial resistance.

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Mechanical computation outperforms electrical computation in applications under extreme conditions. Currently, logic gates can be constructed with mechanical metamaterials, but this may require complex architectures and computing rules, and more complex computations based on these gates are considerably more challenging. Mechanical computing systems with multistability cannot return to their initial stable states, which are hardly reused. Moreover, providing digital electrical outputs is useful to communicate with electrical systems. To address these issues, mechanical metamaterials can be integrated in a manner that is similar to a circuit network with a powerful computing capability. Herein, a general method that combines soft convex and concave modules, rigid frames, and conductive materials in one system to realize logic gates, addition, and multiplication is proposed. The soft modules make or break electrical connections with adjacent frames due to the presence or absence of compressive forces, operating as open and closed switches. Connections and disconnections between modules and frames can be demonstrated with conductive materials and LEDs. The proposed mechanism is simple, versatile, and reusable, allowing soft mechanical metamaterial units to carry out complex computations. The approach may improve the capabilities of soft robots, robotic materials, and microelectromechanical systems.

To understand the different roles played by sheet solids and network solids in complex porous biomaterials/native tissues, we designed a new kind of nature-inspired structure comprising these two solids by using triply periodic minimal surfaces and Voronoi diagrams using the CAD method and compared them with the previously reported Poisson-Voronoi (PV) solids that only comprise network solids. Here, we show that the sheet solids contribute greater stiffness and solid/void interface than the network solids, and our TPMS-Voronoi solids can improve/tune both the elastic moduli and specific surfaces even at fixed solid volume fraction and can be stiffer than the Poisson-Voronoi solids. This can directly guide the porous materials design for use in tissue engineering and aerospace.