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The magnitude and type structure of local government debt are first analyzed in this work. Then, using the “4E” evaluation theory, a local government debt performance assessment index system is built. Second, an entropy-TOPSIS technique is used to calculate the risk index of local government debt performance, and a spatial econometric model is used to examine the geographical spillover impact of local government debt performance across different areas. Finally, the heterogeneity of local government debt management was evaluated using the Malmquist index. The findings demonstrate that the hypothesized national effect is often superior to the sub-regional effects, with a debt ratio regression result of -0.065. Despite the overall local government debt coefficient being -0.032, the direct impact coefficient for the eastern area is -0.025.

Mechanochromic materials have received broad research interests recently, owing to its ability to monitor the in situ stress/strain in polymer materials in a straightforward way. However, one major setback that hinders the practical application of these materials is their low sensitivity toward tensile strain. Here a new strategy for pre‐stretching of the mechanochromic agent in a polymer film on the molecular scale, which can effectively enhance the mechanochromic sensitivity of a polymer film toward tensile strain, is shown. In situ fluorescent measurement during tensile test shows an early activation of the mechanochromic agent at tensile strain as low as 50%. The pre‐stretching effect is realized by first inducing ring‐opening of the mechanochromic agent by molecular functionalization, and then compelling the ring‐closure process in the cured film by elevated temperature. This post‐curing ring‐closure process will result in pre‐stretched mechanochromic agent in a crosslinked network. The mechanism for mechanochromic activation of polymer films with different composition is elaborated by visco‐elastic measurements, and the effect of pre‐stretching is further confirmed by films with other compositions. Combined with the simplicity of the method developed, this work could offer an alternative strategy to enhance the sensitivity of different mechanochromic agents toward tensile strain. [ABSTRACT FROM AUTHOR]

Despite the recent developments in hydrochromic materials, visual detection of water level in plastic materials without sacrificing mechanical properties remains a meaningful yet challenging topic. Currently, to optimize the sensitivity, hydrochromic agents are usually incorporated into hygroscopic matrixes to form bulk solids, which have restricted compatibility for the direct application inside other polymer materials. In this study, this challenge is tackled by nanoscale incorporation of hydrochromic agent into a hygroscopic polymer by miniemulsion polymerization. The obtained hydrochromic nanocapsule has an average diameter ≈110 nm, shows reversible hydrochromic property after 10 cycles, and can offer the first directly eye‐readable signal about the real time in situ water level in plastic materials with a water level below 4 wt.%, while achieving a 214% enhancement of the toughness at the same time. Comprehensive researches by investigating the composition and viscoelastic transition of the nanocapsules has shed light on the mechanisms concerning hydrochromic sensitivity and toughening effect. This simple methodology not only offers a new route for the nanoscale incorporation and application of different hydrochromic materials, but also inspires the development of smart nanoparticles with other stimuli‐responsive functionalities. All these aspects should render this work interesting for both scientific researches and engineering practices. [ABSTRACT FROM AUTHOR]

Objective To investigate the mechanism of miR-451 regulating the resistance of gastric cancer to 5-Fu by down-regulating the expression of MRP. Methods Real-time quantitative PCR was used to detect the relative expression of miR-451 in 20 pairs of human gastric cancer tissues and adjacent tissues and gastric cancer cell lines. The expression of miR-451 in the resistance group and non-resistant group were detected. We constructed gastric cancer cell line with stable plent-miR-451 overexpression, and the overexpression efficiency of miR-451 in gastric cancer cell line was detected by real-time quantitative PCR. The proliferation activity of the cells was detected by CCK8. The miR-451 target gene was analyzed by bioinformatics method and verified by luciferase assay. The effect of miR-451 on the mRNA and protein of targeted gene MRP were detected by real-time quantitative PCR and Western blot. Results The expression of miR-451 in normal tissues was higher than that in cancer tissues, and miR-451 expression in the non-resistant gastric cancer tissues was higher than that in the drug-resistant gastric cancer tissues. The overexpression of miR-451 reduced the resistance of gastric cancer cells to 5-Fu treatment (P=0.0006). Bioinformatics analysis showed that MRP was the target gene of miR-451. Luciferase assay also confirmed that MRP was a potential target gene of miR-451. miR-451 overexpression decreased the mRNA and protein of the drug resistance gene MRP (P=0.00069). Conclusion Overexpression of miR451 could down-regulate MRP expression, which reduces the resistance of tumor cells to 5-Fu.