for their guidance and support throughout the course of my research. Special thanks also go to Jackie Runyan, my copy editor, for her excellent comments and suggestions. My sincere thanks to my graphic design professors, Paula Curran, Beverly Krumm, Cheri Ure, Carol Faber, Lisa Fontaine, Alan Mickelson, and Anson Call, for their generous advice, inspiring guidance and encouragement. In addition, I would also like to thank my friends, Bo Chen, Chen Zhang, Fei Yang, Karen Doty, and Xi Zhu, for making my time at Iowa State University a wonderful experience. Finally, thanks to my family for their encouragement and support and to my husband for his hours of patience, respect, and love.