Accepted for Publication: March 15, 2011.
Author Contributions: All authors had full access to all the data in the study. Dr Stelzle takes responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Nkenke, Vairaktaris, and Holbach. Acquisition of data: Nkenke, Spitzer, Holbach, Knipfer, and Stelzle. Analysis and interpretation of data: Nkenke, Kramer, Stamminger, and Stelzle. Drafting of the manuscript: Spitzer and Knipfer. Critical revision of the manuscript for important intellectual content: Nkenke, Vairaktaris, Kramer, Stamminger, Holbach, and Stelzle. Statistical analysis: Nkenke, Kramer, Stamminger, Knipfer, and Stelzle. Obtained funding: Nkenke and Stamminger. Administrative, technical, and material support: Spitzer, Knipfer, and Stelzle. Study supervision: Nkenke, Vairaktaris, Kramer, and Holbach.
Financial Disclosure: None reported.
Funding/Support: The study was supported by grant NK 453/2-1 from the Deutsche Forschungsgemeinschaft and by the Erlangen Graduate School in Advanced Optical Technologies.