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Slag is widely used as mineral admixtures in cement-based materials by its potential hydration activity. It has the advantage of saving resources and energy, reducing carbon emission, improving the performance of concrete, and plays an increasingly important role in the building materials industry. But the early strength of slag is low, and the industrialization of useful hydration products also need to be activated, so the utilization rate of slag in high grade cement is restricted. The hydration activity of slag depends not only on the content of vitreous in slag, but also on the structure of vitreous slag. To explore slag glass micro composition and structure of its active role, The slag micro-structure was analyzed from the structure levels, and then the factors affecting the activity of slag was evaluated. The potential advantages and disadvantages of some different methods to active slag were discussed such as physical ways, chemical activation method and compound activation way. The existing problems and development direction of improving the activity of slag were summarized , which could provide a valuable reference for the efficient use of slag.

Changes in brain energy metabolism in diabetes mellitus, including increased insulin resistance and mitochondrial dysfunction, are critically involved in diabetes-related neurodegeneration, and associate with early cognitive impairment as well. The aim of this study is to detect the specific phosphorylated-Thr485- AMP-activated protein kinase (AMPK-α2), regulated by cyclin-dependent kinase 5 (Cdk5) paly the inhibitory functional role of AMPK-α2, Which is maybe the link to the accelerated diabetic brain damage progression. Here, we used GK rats, the type 2 diabetic animal model for in vivo studies and performed In vitro kinase assay, high glucose treatment, -phosphorylated mutation and protein expression in both HEK-293T and HT-22 cell lines. In vitro, the results show that murine wild-type AMPK-α2 was phosphorylated by Cdk5 at a (S/T)PX(K/H/R) phosphorylation consensus sequence, which was associated with decreased AMPK-α2 activity. Surprisingly, mutation of Thr485 to alanine in AMPK-α2 results in the abolished Cdk5 effects, demonstrating that Thr485-phosphorylation is critical to AMPK-α2 inhibition by Cdk5. In addition, these alterations in AMPK-α2-phosphorylation and -activity induced by Cdk5 is specific at Thr485. Furthermore, in GK rats, the increased phosphorylated- Thr 485 of AMPK-α2 results in the decreased AMPK-α2 activity, which is correlated with the apoptosis of neurons in hippocamps. After high glucose treatment, the decreased survival showed in AMPK-α2T485A HT-22 cells compared to AMPK-α2WT. The down-regulated of p-CREB, SNAP25, synaptophysin as well as synapsin-1were shown in both GK rats and HT-22 cell line. Meanwhile, pre-treated with either the specific Cdk5-inhibitor (roscovitine) or the antidiabetic AMPK-α2-inhibitor (metformin) could restore the alterations in neuronal protein expression. Our results suggest that Cdk5-mediated phosphorylated- Thr485 in AMPK-α2 may be involved in the pathogenesis of diabetic brain damage.

C–S–H-PCE nanocomposites (CPNs) serving as nucleation sites are a promising material to accelerate the cement hydration and gain high early strength for cementitious materials. This study aimed to investigate the effects of CPNs on the properties and hydration of cement mortar under different water-to-cement (w/c) ratios. CPNs were prepared via the co-precipitation method in MAPEG-PCE solution and characterized by means of XRD, FT-IR, DLS, TEM , TGA, and TOC . The mechanism and effect of CPNs on the early hydration of cement mortar with w/c ratios of 0.50, 0.40, and 0.35 were assessed in terms of mechanical properties, isothermal calorimetry, setting time XRD, TGA, SEM, and MIP. The results showed that CPNs significantly promoted the early strength development of mortar and a higher enhancement ratio was brought at a lower w/c ratio. Calorimetry and setting results also showed a greater hydration acceleration of samples dosed CPNs with lower w/c ratio. From the analysis of XRD and TGA, the content of CH and C–S–H in the samples dosed CPNs increased with the decrease of w/c ratio in 6 h, while exhibited an opposite trend in 12 h and 3 d. MIP and SEM results showed that CPNs led to a refinement of pore structure and dense morphology, especially at a low w/c ratio. Moreover, the underlying acceleration mechanism of cement hydration versus w/c ratio was that the seeding ability was enhanced for the low distance between cement and CPNs at a low w/c ratio. According to this research, the use of CPNs may be more practical in high-strength concrete.