1. School of Natural Resources, University of Nebraska-Lincoln, Lincoln, Nebraska.
2. Department of Biostatistics, University of Nebraska Medical Center, Omaha, Nebraska.
3. Department of Psychology, Colorado State University, Fort Collins, Colorado.
4. Nebraska Department of Health and Human Services, Lincoln, Nebraska.
5. Division of Hematology/Oncology, University of Nebraska Medical Center, Omaha, Nebraska.
6. Department of Statistics, University of Nebraska-Lincoln, Lincoln, Nebraska.
7. Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska.