Compounds are provided that act as potent antagonists of the CCR2 or CCR9 receptor. The automatic reel includes a control system having a motor controller capable of sensing a pulling of, or increased tension of, the linear material and capable of causing a motor to rotate to unspool the linear material. In another embodiment, a system includes interfaces for meaning taxonomy, expert rule and search criteria information. Another technique considers node disjointness and provides a solution of two paths that are as node disjoint as possible and minimizes administrative costs.