Advances in ultra high molecular weight polyethylene/hydroxyapatite composites for biomedical applications: A brief review.

Ultra high molecular weight polyethylene (UHMWPE) is a semicrystalline polymer that has been applied, as a bearing surface in total human joint replacements and artificial bones. UHMWPE has a superior wear resistance, low-friction surface, biological inertness, high levels of strength, creep resistance and low friction coefficient. However, the wear debris generated during the joint motions could cause problem in human implant, such as osteolysis and loosening.

Aqueous extracts of Mozambican plants as alternative and environmentally safe acid-base indicators.

Indicators are substances that change color as the pH of the medium. Many of these substances are dyes of synthetic origin. The mulala plant (Euclea natalensis), which roots are commonly used by rural communities for their oral hygiene, and roseira (Hibiscus rosa-sinensis), an ornamental plant, are abundant in Mozambique.