Leadership and Cultural Change are important. Create a Hypothesis on how these two are linked and the outcome is significant value growth for a company with a broken culture (complaining, poor workmanship, poor attitudes, lack of effort and energy and high turnover). An excellent resource will be the book "Competing values leadership: creating value in organizations."
Click on books, then my books, and all three should be listed.
Develop a new extended concept on this selected topic so that you provide a different conceptual position on what previous research is offered. Talk about this topics evolution and provide rationale for the extension of your new theory. Define your theory qualitatively and give suggested quantitative support.