1. Department of Biochemistry and Molecular Biology; University of Texas, Medical School at Houston; Houston TX 77030 USA
2. Department of Applied Computer Science and Modeling; AGH University of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science; Krakow Poland
3. Department of Computer Science; AGH University of Science and Technology; Krakow Poland
4. Department of Minnesota Supercomputing Institute; University of Minnesota; Minneapolis MN 55455-0219 USA