Combinations of individual colorant compounds that provide effective toning to combat yellowing within polyester articles are provided. Additionally, a component scheduling method and apparatus in robot software are provided. The ligating devices comprise a ligating element and a control element which controls the opening of the ligating element in a loop or lariat shape. The personal speech recognition parameters for the speaker are selected and used to convert the sound data to text data. Thus, it is not necessary for an operator to perform positioning and fixation guiding operations again, thereby contributing to a shorter imaging time and less complexity and trouble in the overall operation. The composition of the invention are basically comprised of a hydraulic cement, sufficient water to form a slurry and hollow glass microspheres surface treated with a mixture of organosilane coupling agents present in an amount sufficient to produce a cement composition density in the range of from about 6 to about 12 pounds per gallon.