1. United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, 1100 Robert E. Lee Boulevard, New Orleans, Louisiana 70124, United States
2. Department of Mathematics, University of New Orleans, 2000 Lakeshore Drive, New Orleans, Louisiana 70148, United States
3. Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Tsinghua East Road, Beijing, 100083, China