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AIM: To investigate the protective effect and mechanism of Danlou tablet on retinal ischemia-reperfusion injury(RIRI)in mice.METHODS: A total of 40 ApoE-/- mice were fed with high fat diet for 6 wk, and the RIRI model was established by anterior chamber infusion of pressurized saline. The mice were divided into control group(normal saline for 8 wk), RIRI model group(normal saline for 8 wk), and low-, medium-, and high-dose Danlou tablets groups [1, 2, and 4 g/(kg·d), respectively, for 8 wk]. The morphological changes of retina were observed by hematoxylin-eosin(HE)staining, retinal cell apoptosis was detected by terminal-deoxynucleoitidyl transferase mediated Nick-End Labeling(TUNEL)staining. The Western-blot assay was used to detect the expression of retinal tissue sample Kelch-like ech-associated protein 1(Keap1), nuclear factor E2 related factor 2(Nrf2), heme oxygenase 1(HO-1), and superoxide dismutase(Sod2)proteins.RESULTS: Compared with the control group, the mouse retina was atrophic with thinning thickness and increasing cell apoptosis, down-regulation of Sod2 protein expression, and up-regulation of Keap1 protein expression in the RIRI model group(all P0.05). The expression of Sod2, Nrf2 and HO-1 proteins up regulated, and the expression of Keap1 protein down regulated in the medium- and high-dose of Danlou tablets groups(all P

The Integration of Professional Education and Innovation and Entrepreneurship Education (IPEIEE) has been recognized as an important direction for the development of higher education in enhancing the innovation and entrepreneurship awareness and ability of college students. However, universities and teachers are facing challenges while promoting IPEIEE, namely, various stakeholders, the unreasonable design of the curriculum system, and the lack of relevant incentive policies. In addition, IPEIEE in many universities has been placed on hold. Few studies have examined the innovation regime in IPEIEE, despite it being a dilemma that the field confronts. Thus, taking into account the roles of universities, teachers, and students in the evolutionary game model, this paper firstly constructs an evolutionary game model for teachers and students, in which the costs and parameters affecting the benefit matrix, as well as the stability strategy, are refined. Secondly, the behavior of universities is introduced to examine the effects of universities on strategic choices of teachers and students. Finally, a mechanism analysis is conducted in combination with the principal–agent model to gain a deeper understanding of the evolutionary stability of stakeholder strategies in the IPEIEE. The findings emphasize potential Evolutionary Stable Strategies (ESS) that universities, as promoters and guides, should take as measures concerning both economic encouragement and management encouragement to promote IPEIEE, so as that the 'ideal state' can be achieved. Furthermore, if specific incentives for different stakeholders are proposed and set at an appropriate intensity, this will encourage active cooperation among these stakeholders. This paper explores the evolution mechanism of innovation strategies in IPEIEE from the perspective of stakeholders, offering a better comprehension of the dynamic evolution of these strategies. The key findings also offer support for policymakers to promote the mutual development of agents in the IPEIEE, thus enhancing the overall sustainable collaborative capability of the IPEIEE. [ABSTRACT FROM AUTHOR]

This study investigated the mechanical properties and stress–strain relationship of polypropylene fiber recycled aggregate concrete (PFRAC) subjected to uniaxial cyclic compression. A total of 78 cylindrical specimens were designed for uniaxial cyclic compression test with coarse aggregate replacement rate, polypropylene fiber volume fraction, and loading rate as variation parameters. The failure process of the specimens under cyclic loading was observed and recorded. The stress–strain curve of PFRAC was summarized. The important mechanical properties of PFRAC were obtained, such as plastic strain, accumulated energy dissipation. The microstructure of PFRAC was analyzed by scanning electron microscopy, and the crack resistance mechanism of PFRAC under cyclic loading was revealed. The results show that the PFRAC under cyclic loading appeared oblique splitting failure. The compressive stress–strain curve envelope of PFRAC subjected to cyclic loading exhibited similarity to the monotonic counterpart. The addition of polypropylene fibers can improve the peak stress, peak strain, residual stress, post‐peak ductility, and accumulated energy dissipation of the recycled concrete. In addition, a constitutive relation formula for the PFRAC stress–strain curve under cyclic loading is proposed, and the fitting result is good. [ABSTRACT FROM AUTHOR]

In order to study the compressive behavior of carbon fiber recycled aggregate concrete (CFRAC) under cyclic loading, 40 cylindrical specimens were designed and fabricated for cyclic loading test with recycled coarse aggregate replacement rate, carbon fiber volume content and loading rate as variation parameters. The test observed the failure mode of the specimen, obtained the stress-strain curve, and analyzed the influences of different variation parameters on the mechanical behaviors such as peak stress, peak strain, plastic strain, stiffness degradation and stress degradation. The results show that the carbon fiber recycled aggregate concrete specimens mainly undergo oblique splitting failure under cyclic loading. The incorporation of carbon fiber improves the cyclic compression performance of recycled aggregate concrete. Compared with unmixed carbon fiber concrete, when the volume content of carbon fiber is 0. 3%, the peak stress and peak strain increase by 11. 33% and 12. 22%, respectively. The degree of stiffness degradation and stress degradation is reduced. When the replacement rate of recycled coarse aggregate is 100%, the peak stress and peak strain increase by 10. 16% and 14. 29%, respectively. Finally, the stress-strain constitutive equation of carbon fiber recycled aggregate concrete under cyclic compression is proposed. [ABSTRACT FROM AUTHOR]