Restoration of the cantilever bowing distortion in Atomic Force Microscopy

Due to the mechanics of the Atomic Force Microscope (AFM), there is a curvature distortion (bowing effect) present in the acquired images. At present, flattening such images requires human intervention to manually segment object data from the background, which is time consuming and highly inaccurate. In this paper, an automated algorithm to flatten lines from AFM images is presented. The proposed method classifies the data into objects and background, and fits convex lines in an iterative fashion. Results on real images from DNA wrapped carbon nanotubes (DNACNTs) and synthetic experiments are presented, demonstrating the effectiveness of the proposed algorithm in increasing the resolution of the surface topography. In addition a link between the flattening problem and MRI inhomogeneity (shading) is given and the proposed method is compared to an entropy based MRI inhomogeniety correction method

Nepotism or Family Tradition?: A Study of NASCAR Drivers

Of the drivers who raced NASCAR cup series in 2005, 23 of 76 had family connections of either being a son, brother or father of current or former drivers. Given the family connections, some have suggested that the N in NASCAR stands for nepotism. The family tradition of career following, however, is not unique to NASCAR. We see this pattern in many careers such as business, law, politics, agriculture, medicine and entertainment. There are many reasons why children enter the same career as their parents. These include physical-capital transfer, human-capital transfer, brand-nameloyalty transfer, and nepotism. Using a panel data of career statistics for drivers from the last 30 years, we test to see which model best explains career following in NASCAR racing. Our results suggest that the N in NASCAR does not stand for nepotism. Sons, do not have longer careers than non family connected drivers, given the same level of performance. We do find, however, that fathers end their careers earlier than performance indicates when a son enters into cup competition. This could be due to a son’s ability to extend a brand name across generations. The extension of a brand name also occurs with second brothers who benefit from the first brother’s name and having longer careers than performance indicates. If nepotism exits, it occurs only with the second brothers.