RESUMO
We applied the Hurst exponent technique to an experimental study of rough metallic surface profiles and the speckle patterns generated by them. Characterization of important statistical properties of the surface profile and speckle patterns were performed. We observed a clear correlation between the Hurst exponent of a surface profile and the one calculated from the associated speckle patterns. Therefore, in principle, information of the Hurst exponent of the profile can be obtained from the Hurst exponent of speckle patterns. Range and sampling analyses were performed in the Hurst exponent calculations showing the robustness of the method. As an additional application, we performed a basic simulation to show that the Hurst exponent is sensitive to surface waviness.
RESUMO
In the 1990s more than 41,000 patients underwent high-dose chemotherapy plus autologous bone marrow transplant (HDC-ABMT) for breast cancer, despite a paucity of clinical evidence of its efficacy. Most health plans reluctantly agreed to cover the treatment in response to intensive political lobbying and the threat of litigation. The results of five recent major randomized trials showed that HDC-ABMT offers no advantage over standard-dose treatment for breast cancer. Our experience with HDC-ABMT coverage cautions against allowing politics to overwhelm science in the area of evaluating experimental procedures, and against relying on the courts as a means of resolving disagreements about coverage of these interventions.
