A device for insertion in a high-heeled shoe has a first crescent shaped raised area in a region underlying the forward edge of a wearer’s heel bone and a second raised area underlying the metatarsals of the wearer is described. The acetabular cup is attached to acetabular bone, and the anti-protrusio cage is thereafter mounted to the inner surface of the acetabular cup. Each differential pair has two lines including one or more parallel portions extending substantially parallel to each other. This prevents pressure vibration and avoids the complexity of advective term calculation. More particularly, the particle size distribution of each of the metal acetylacetonates is a function of its melting temperature, and optionally of its melting temperature and solubility. More specifically, wireless network access point data may be used to identify the position of a mobile device in an indoor space, which, in turn, may be used to identify products within the vicinity of the identified position.