Effect of Rice Husk Ash on the Properties of Alkali-Activated Slag Pastes: Shrinkage, Hydration and Mechanical Property.

In this paper, rice husk ash (RHA) with different average pore diameters and specific surface areas was used to replace 10% slag in the preparation of alkali-activated slag (AAS) pastes. The effect of RHA addition on the shrinkage, hydration, and strength of AAS pastes was studied. The results show that RHA with a porous structure will pre-absorb part of the mixing water during paste preparation, resulting in a decrease in the fluidity of AAS pastes by 5-20 mm. RHA has a significant inhibitory effect on the shrinkage of AAS pastes. The autogenous shrinkage of AAS pastes decreases by 18-55% at 7 days, and the drying shrinkage decreases by 7-18% at 28 days. This shrinkage reduction effect weakens with the decrease in RHA particle size. RHA has no obvious effect on the type of hydration products of AAS pastes, whereas RHA after proper grinding treatment can significantly improve the hydration degree. Therefore, more hydration products are generated and fills the internal pores of the pastes, which significantly improves the mechanical properties of the AAS pastes. The 28 day compressive strength of sample R10M30 (the content of RHA is 10%, RHA milling time is 30 min) is 13 MPa higher than that of blank sample.

Optimization of NAMPT activators to achieve in vivo neuroprotective efficacy.

NAMPT is the rate-limiting enzyme in the NAD salvage pathway, which makes it an attractive target for the treatment of many diseases associated with NAD exhaustion such as neurodegenerative diseases. Herein, we present the systematic optimization of NAT, an initial hit of NAMPT activator discovered by us through high-throughput screening, based on the co-crystal structure of the NAMPT-NAT complex. Over 80 NAT derivatives have been designed and synthesized, among which compound 72 showed notably improved potency as NAMPT activator and effectively protected cultured cells from FK866-mediated toxicity. Moreover, compound 72 exhibited strong neuroprotective efficacy in a mouse model of chemotherapy-induced peripheral neuropathy (CIPN) without any overt toxicity, which renders it a promising candidate for the development of novel neuroprotective agents.