School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, USA.|Baidu Research USA, Sunnyvale, CA, USA.|School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, USA.|School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, USA.|School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, USA.|School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, USA.|Department of Biochemistry & Biophysics, University of Rochester Medical Center, Rochester, NY, USA.