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The aim of this study is to evaluate the behavior of glass powder waste as alkaline activator of slag when both are used in blended cement. The slag blended cement was prepared with 70% slag, and then the slag was replaced with 10-20% glass powder by mass. The self-activation concept is here introduced. Ground glass releases alkalis through dissolution in a slow and sustained way over time. This would activate slag. Ground glass improves fluidity of mortars and the compressive strength overcomes dilution and increases with age due to the combined pozzolanic action of slag and glass. The proposed blended cement has better mechanical properties than slag-cement. The proposed blended cement has better mechanical properties than slag-cement and due to less use of slag, it becomes more sustainable and it contributes to waste management., El objetivo del presente trabajo es evaluar el comportamiento de un residuo molido de vidrio como activador interno de la escoria cuando ambos son usados en un cemento mezcla. El cemento de escoria fue preparado con un 70% de escoria y luego la escoria se reemplazó en un 10 y 20% en masa por vidrio molido. Este trabajo introduce el concepto de auto-activación. El vidrio molido libera álcalis por disolución, en forma lenta y sostenida en el tiempo que activarían la escoria. La presencia de vidrio molido mejora la fluidez de los morteros y la resistencia a compresión supera la dilución y crece con la edad por la acción puzolánica combinada de la escoria y el vidrio. El cemento mezcla propuesto tiene mejores propiedades mecánicas que el cemento de escorias pero con menor contenido de escoria por lo que es más sustentable y contribuye al manejo de residuos.

Demolition ceramic wastes (DCWs) were investigated in order to determine their potential use as supplementary cementitious materials in Portland Blended Cements (PBCs). For this purpose, three ceramic wastes were investigated. After characterization of the materials used, the effect of ceramic waste replacement (8, 24 and 40% by mass) was analyzed. Pozzolanic activity, hydration progress, workability and compressive strength were determined at 2, 7 and 28 days. The results showed that the ground wastes behave as filler at an early age, but as hydration progresses, the pozzolanic activity of ceramic waste contributes to the strength requirement., Se estudiaron residuos cerámicos de demolición (DCWs) a fin de determinar su potencial uso como materiales cementicios suplementarios en cementos mezcla (PBC). Para este propósito, se investigaron tres residuos cerámicos. Luego de la caracterización de los materiales a utilizar, se analizó el efecto del reemplazo por residuos cerámico (8, 24 y 40% en peso). Se estudió la actividad puzolánica, el progreso de la hidratación, la trabajabilidad y la resistencia a compresión a 2, 7 y 28 días. Los resultados mostraron que los residuos molidos se comportaron como fillers a edades tempranas, pero con el progreso de la hidratación, la actividad puzolánica de los residuos cerámicos contribuye a los requerimientos de resistencia.

Background & Aims The psychometric hepatic encephalopathy score (PHES), which includes 5 psychometric tests, is a standard for the diagnosis of minimal hepatic encephalopathy (HE). We investigated whether a simplified PHES (SPHES) is as useful as the whole PHES. Methods The PHES was determined for 79 cirrhotic patients (the training group), who were followed up for the development of overt HE. Backward logistic regression was performed by eliminating stepwise variables—removal did not impair regression. A separate series of 65 patients was used as a validation group. Results The PHES was abnormal in 45 patients. The SPHES, determined from the digit symbol, serial dotting, and line tracing tests, did not differ significantly from the full PHES; 24 of the 79 patients developed overt HE. The likelihood of developing overt HE was higher among patients with an abnormal PHES (log-rank P = .003) or SPHES ( P = .004). By using Cox regression and model for end-stage liver disease scores to analyze data from patients with previous HE and transjugular intrahepatic portosystemic shunts, PHES (relative risk, 4.16; P = .003) and SPHES (relative risk, 3.70; P = .004) were the only variables associated with the development of overt HE. The accuracy of the SPHES was confirmed in the validation group. Conclusions A simplified PHES is as good as the PHES in diagnosing minimal HE and in predicting the occurrence of overt HE.