1. Department of Nutrition, Dietetics and Food Science, Brigham Young University, S221 ESC, Provo, UT 84602.
2. Corresponding author. Phone: 801-422-6671. Fax: 801-422-0258. E-mail: oscar_pike@byu.edu
3. Center for Statistical Consultation and Collaborative Research, Brigham Young University, 223 TMCB, Provo, UT 84602.
4. Department of Integrative Biology, Brigham Young University, 401 WIDB, Provo, UT 84602.