Quantifying the Workability of Calcium Sulfoaluminate Cement Paste Using Time-Dependent Rheology.

Poor workability is a common feature of calcium sulfoaluminate (CSA) cement paste. Multiple chemical admixtures, such as set retarders and dispersants, are frequently employed to improve the workability and delay the setting of CSA cement paste. A quantitative assessment of the compatibility, efficiency, and the effects of the admixtures on cement paste workability is critical for the design of an appropriate paste formulation and admixture proportioning.

Setting Times of Early-Age Mortars Determined from Evolution Curves of Poisson's Ratio.

Setting times, as the early-age properties of cement-based materials, are important properties to ensure the quality and long-term performance of engineering structures. To determine the initial and final setting times of cementitious materials, the compressive wave velocity and shear wave velocity of six early-age mortar samples were monitored. Their time evolution curves of Young's modulus, shear modulus, bulk modulus, and Poisson's ratio were then calculated and analyzed.

Prevalence and severity of traumatic dental injuries among young amateur soccer players: A screening investigation.

Background/aims: Traumatic dental injuries (TDI) are prevalent among soccer players. In Kuwait, no studies of TDI among soccer players have been carried out. The aim of this study was to investigate the prevalence, type and causes of soccer-related traumatic dental injuries among 7-18-year-old amateur soccer players.

[When to ask for a skin biopsy in a patient with leg ulcer? Retrospective study of 143 consecutive biopsies].

Objective: A vascular cause is found in around 85% of leg ulcer patients, but non-vascular causes are also observed. Their diagnosis is based on a set of clinical arguments and skin biopsy with histological analysis. The aim of this study was to analyze the results of these biopsies and to find common criteria for ulcers whose skin biopsies had led to the diagnosis of a non-vascular ulcer.

Factorial Design Approach in Proportioning Prestressed Self-Compacting Concrete.

In order to model the effect of mixture parameters and material properties on the hardened properties of, prestressed self-compacting concrete (SCC), and also to investigate the extensions of the statistical models, a factorial design was employed to identify the relative significance of these primary parameters and their interactions in terms of the mechanical and visco-elastic properties of SCC. In addition to the 16 fractional factorial mixtures evaluated in the modeled region of -1 to +1, eight axial mixtures were prepared at extreme values of -2 and +2 with the other variables maintained at the central points. Four replicate central mixtures were also evaluated.