PURPOSE The aim of the study was to report the long-term clinical performance of esthetic primary molar crowns and compare them to that of stainless steel crowns (SSC). METHODS Twenty crowns (10 conventional and 10 esthetic) placed in 10 children who had participated in a previously reported study, were assessed again after 4 years. The crowns were evaluated clinically and radiographically ac...

This study investigates the optimal supply chain design for commodity chemicals (BTX, etc.) production via woody biomass fast pyrolysis and hydroprocessing pathway. The locations and capacities of distributed preprocessing hubs and integrated biorefinery facilities are optimized with a mixed integer linear programming model. In this integrated supply chain system, decisions on the biomass chipp...

Here we show how a migratory songbird, the chipping sparrow (Spizella passerina), achieves prompt and precise vocal imitation. Juvenile chipping sparrow males develop five to seven potential precursor songs; the normal development of these songs requires intact hearing but not imitation from external models. The potential precursor songs conform with general species-typical song parameters but ...

OBJECTIVE The aim of this multicenter randomized controlled clinical trial was to test posterior zirconia-ceramic fixed dental prostheses (FDPs) veneered with a computer-aided design/computer- assisted manufacture (CAD/CAM) lithium disilicate veneering ceramic (CAD-on) and manually layered zirconia veneering ceramic with respect to survival of the FDPs, and technical and biologic outcomes. ME...

The study determined the time consumption, fuel consumption and chip size obtained with two different industrial chippers, working with logging residues (tops and branches), thinning material and pulpwood. Specific time consumption per oven dry tons (odt) was 83% higher for the less powerful disc chipper, and chipping forest residues resulted in a 35% increase in specific time consumption compa...

An increased incidence of fracture has been reported in teeth where root canals were treated with calcium hydroxide. Edge chipping is one test used to measure the resistance of brittle materials to fracture. Presently, no studies have reported on edge chipping in teeth. This study evaluated the fracture resistance of human dentin exposed to calcium hydroxide for up to 60 days using the edge chi...

physics.ubs.ca Imagine stepping off the edge of a swimming pool, only to find that your foot deflects the surface of the water without breaking it, as if held by some impenetrable skin. As you walk forward, the water continues to support you; but if you take a running leap and bring your full weight down on the surface, then it snaps open to envelop you without a splash. Rather than plunging to...