Introduction Since the late 1950s and early 60’s, conventional calcium hydrogen phosphate has been widely used as the excipient for direct compression tabletting. However, the fi rst generation of calcium phosphates were hard and rough pillar-like crystals with crystal water, which often caused abrasiveness of punches and dies in tabletting. In addition, the crystal water could possibly be rele...

Dietary hardness and abrasiveness are inferred from human dental microwear at Ohalo II, a late Upper Palaeolithic site (22,500-23,500 cal BP) in the southern Levant. Casts of molar grinding facets from two human skeletons were examined with a scanning electron microscope. The size and frequency of microwear was measured, counted, and compared to four prehistoric human groups from successive chr...

Abstract In any underground excavation project, choosing the best technique and careful preliminary assessments of wear costs production rates are crucial aspects to consider. The rate tools, as well frequency tool replacement, deeply affect duration cost‐effectiveness whole project. Among rock‐specific characteristics affecting wear, Cerchar abrasivity index (CAI) uniaxial compressive strength...

This study analyzed the weight loss and surface roughness caused in Plexiglass specimens by conventional dentifrices (Sorriso, Colgate and Close Up) and specific dentifrices used for cleaning of dentures (Corega and Dentu Creme). Plexiglass specimens were divided into 6 groups (n=6) including: a control (distilled water - DW) and experimental groups. Brushing was performed in a toothbrushing ma...

the production of colony-stimulating factors (csf) is delicately controlled through a complex network of humoral and environmental factors. we have studied some of the mechanisms which regulate the production of csf as compared to general protein synthesis in the lung tissue ill vitro. when lung tissue from mice was cultured for various times in serum free medium, the first detectable level of ...

Objective: This in vitro study was aimed to assess the abrasiveness of 4 different composite finishing and polishing systems, on two nano-hybrid materials.
 Methods: 40 disc samples were prepared mm diameter 2 thickness for each resin (Tetric EvoCeram BulkFill A1 body IPS Empress Direct A1; Ivoclar Vivadent, Schaan, Lichtenstein; n=80 total). Each group divided into system subgroups (Sof-L...

a rahalt-chromium (Co-Cr) alloy using a centrifugal shooting type polishing machine. In tha present work, we examined the effects of the texture of polishing particle and polishing time on the surface roughness of Co-Cr alloy cast specimens. Nine differcnt textures of polishing par'ticle were investigated wiLh respect to core material and paTticle abrasiveness: three (lifferent elastic body cer...