A B S T R A C TGovernments are increasingly emphasizing emergency management in response to public emergencies that cause extensive consequences and involve multiple government agencies. One of the influential measures adopted by governments is the establishment of cross-agency networks. Scholars have validated the importance of cross-agency collaboration and networks, but only a few studies have examined cross-agency information sharing and utilization mechanism of joint emergency actions. Inspired by the theory of network embeddedness, we study the joint effects of informational and task attributes of embeddedness and absorptive capacity of the leading agency on collaborative emergency capacity. Our data consist of 110 local government contingency plans collected from F District in Shanghai, China. We found that a well-structured cross-agency network and a leading department with great information accessibility will significantly affect the efficiency of emergency collaborations. The capacity to absorb information significantly enhances the improvement of emergency collaboration.

Shape memory polymers (SMPs) have gained much attention in biomedical fields due to their good biocompatibility and biodegradability. Researches have validated the feasibility of shape memory polymer stent in treatment of vascular blockage. Nevertheless, the actual application of SMP stents is still in infancy. To improve the mechanical performance of SMP stent, a new geometric model based on metamaterial is proposed in this study. To verify the feasibility and mechanical behavior of this type of stent, buckling analysis, and in vivo expansion performance of SMP stent are simulated. Numerical results exhibit that stent of a smaller radius behaves a higher critical buckling load and smaller buckling displacement. Besides, a smaller contact area with vessel and smaller implanted stress are observed compared with traditional stents. This suggests that this SMP stent attributes to a reduced vascular restenosis. To characterize the radial strength of SMP stent, an analytical solution is derived by the assumption that the deformation of stent is mainly composed of bending and stretch. The radial strength of SMP stent is assessed in form of radial force. Analytical results reveal that radial strength is depended on the radius of stent and periodic numbers of unit cell in circumferential direction.

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Purpose The purpose of this paper is to demonstrate the feasibility of using shape memory polymer (SMP) for developing vascular stent. In particular, the expansion performance is analyzed through extensive modeling and simulation. Design/methodology/approach Firstly, the authors construct the model geometry and propose a constitutive model to describe the deformation of the stent due to the expansion process. The authors then simulate the expansion process under varying conditions, including different heating rates and recovery temperatures. Finally, the authors analyze the radial strength of the SMP stent. Findings A less invasive and stable expansion performance of the SMP stent is confirmed by the simulation method. A fitting function of the expansion process is proposed based on the characteristics of the SMP. Research limitations/implications The effects of dynamic blood flow on the SMP stent is ignored. A fluid-structure interaction analysis may need to be considered to give a more accurate description of the behaviour of the SMP stent. Practical implications The findings will provide guidance for the rational design and application of SMP stents. Social implications The work will provide guidance for the new generation stent design. Originality/value This is the first time that the expansion performance of a SMP stent has been analyzed both qualitatively and quantitatively through modelling and simulation.

The one-dimensional Li+ diffusion channel is the key factor restricting the rate performance and low-temperature performance of LFP/C composites. By artificially creating a certain content of anti-site defects, the Li+ in the LFP material can be diffused two-dimensionally. The LFP/C composites synthesized by the carbothermic reduction method at 700°C have 3.77% Fe-Li anti-site defects, showing higher rate performance, cycle performance, and discharge specific capacity. The CV, EIS, and GITT tests show that the Li+ diffusion coefficient of LFP is the highest when the content of Fe-Li anti-site defects is 3.77%. DFT calculation shows that the single pair of Fe-Li anti-site defects is conducive to the two-dimensional diffusion of Li+, while the continuous two pairs of anti-site defects greatly inhibit the diffusion of Li+ along the original [010] crystal direction.