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Rapid urbanisation causes a rise in the need for infrastructure, which in turn fuels the creation of additional concrete and further increases cement supplies. Activation of illite-based clay mineral and usage in concrete production is one of the sustainable ways to address the cement industry anthropogenic issues. This study evaluates the durability properties of water transport (water absorption, and capillary water absorption), and resistance to aggressive environments (5% solutions of hydrochloric acid, HCl; sodium sulphate, Na 2 SO 4 ; and calcium chloride, CaCl 2 ) of meta-illite calcined clay (MCC)-based high-performance concrete (HPC). For this purpose, concrete was produced with 5, 10, 15, 20, 25 and 30% MCC content in partial substitution of CEM II. Results from the water absorption tests indicate an average percentage value of 3.57%, 3.35% and 2.52% for all the observed mixes at 28, 56 and 90 days, respectively, with MCCC-10 HPC having an average best value of 2.23% across the curing ages. On all observed days, the 5 to 15% cement replacements had very close average water sorptivity value of 0.125 ± 0.001 mm/min 0.5 with the control mix (0.113 ± 0.011 mm/min 0.5 ). The aggressive environments exposure findings of the hardened MCC-based HPC specimens of 10 to 20% recorded an approximately 15% compressive strength loss in HCl, Na 2 SO 4 and CaCl 2 solutions over the 90 days of curing. In all, the HPC mixes of 5 to 15% MCC content obtained an average durability performance factor of 89%. As a result, these findings imply that MCC can replace cement in up to 15% of HPC production.

In the construction industry, cement is the most widely used material. So, to achieve greater sustainability in this industry, it is imperative to improve the sustainability of this material. One way to reduce the ecological footprint of cement is to replace it, even if partially, with other more sustainable materials that can act as binders. This paper analyses the mechanical properties of more sustainable mortars containing recycled cement (RC), fly ash (FA), and magnesium oxide (MgO). Different types of binary, ternary, and quaternary mortars were used: containing recycled cement (5% and 10%), fly ash (10% and 20%), and MgO (7.5% and 15%). An experimental campaign was carried out analysing air content, density, compressive and flexural strengths, modulus of elasticity, and ultrasonic pulse velocity. The ternary mortars showed decreases between 0.4% (M-5RC10FA) and 35.3% (M-10RC15Mg) in terms of compressive strength at 365 days (compared to RM), when the theoretically expected decrease (the sum of the decreases obtained with the individual incorporation of these materials) would be between 16.6% and 41.5%, respectively. The results obtained allow for concluding that the joint use of these materials in ternary mortars improves the mechanical capacity, relative to the individual incorporation of each material in binary mortars.

Objectives: The optimal timing for delivery in non-severe late-preterm (34 + 0-36 + 6 weeks) preeclampsia (PE) is uncertain. It is attempted to reach term pregnancy safely but current clinical and analytical parameters fail to determine which cases will develop severe features that require preterm delivery. We aim to establish if angiogenic biomarkers may identify cases that would benefit from earlier delivery., Study Design: Prospective case-control study of 96 women (n = 48 controls and n = 48 cases with PE) with maternal determinations of the sFlt-1/PlGF ratio between 34 + 0 and 36 + 6 weeks. The PE group was classified in two groups based on the need (n = 26) or not (n = 22) for preterm delivery due to criteria of severity. Diagnostic accuracy of these biomarkers for predicting preterm delivery for severe PE was evaluated., Main Outcome Measures: Women with PE showed higher median sFlt-1/PlGF ratio than controls (122 vs 5, p < 0.01) and lower PlGF MoM (0.7 vs 1.0, p < 0.01). However, these differences did not remain when both PE subgroups were compared. Diagnostic performance of the sFlt-1/PlGF ratio and PlGF at different cut-offs was poor for detecting PE requiring delivery before term., Conclusions: Angiogenic biomarkers are not useful to predict which late-preterm PE cases will develop severe features that require preterm delivery., (Copyright © 2019 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.)