Bede Pittenger

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Established techniques for global gene expression profiling, such as microarrays, face fundamental sensitivity constraints. Due to greatly increasing interest in examining minute samples from micro-dissected tissues, including single cells, unorthodox approaches, including molecular nanotechnologies, are being explored in this application. Here, we examine(More)
We have indented the surface of ice at temperatures between 21 °C and 217 °C with sharp atomic force microscope tips. For a thick viscous interfacial melt layer, a Newtonian treatment of the flow of quasiliquid between the tip and the ice suggests that indentations at different indentation velocities should have the same force/velocity ratio for a given pit(More)
A cantilever type has been developed for dynamic force microscopy by the addition of a harmonic oscillator in the form of a paddle to atomic force microscopy cantilevers. These cantilevers provide resonant amplification of periodic interactions between the probe and the substrate when the laser is aligned on the paddle. The cantilevers were explored for(More)
We report on quantifiable depth-dependent contact resonance AFM (CR-AFM) measurements over polystyrene-polypropylene (PS-PP) blends to detail surface and sub-surface features in terms of elastic modulus and mechanical dissipation. The depth-dependences of the measured parameters were analyzed to generate cross-sectional images of tomographic(More)
A novel preamplifying cantilever (PCL) design for scanning probe microscopes (SPM) that is capable of mechanically amplifying specimen movements is presented. The sample motions in both out-of-plane and in-plane directions are amplified by the PCL. The spatial resolution of the cantilever is in the nanometer scale and is comparable with existing SPM(More)
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