An optical fiber cable comprising a polymeric jacket and at least one elongated buffer tube having a substantially circular cross-section and at least one optical fiber disposed within the at least one buffer tube. The refined molten material is provided to the atomizing nozzle of the nucleated casting apparatus through a transfer apparatus adapted to maintain the purity of the molten refined material. The invention further discloses a method and device for generating a user movement track and a device for generating a user mobility model. The porous layer has a three dimensional density ranging from about 20 mg collagencm3 to about 200 mg collagencm3.