Dielectric constants by multifrequency non-contact atomic force microscopy.

We present a method to obtain capacitive forces and dielectric constants of ultra-thin films on metallic substrates using multifrequency non-contact atomic force microscopy with amplitude feedback in air. Capacitive forces are measured via cantilever oscillations induced at the second bending mode and dielectric constants are calculated by fitting an analytic expression for the capacitance (Casuso et al 2007 Appl. Phys.

Histone H3.3 deposition at E2F-regulated genes is linked to transcription.

The histone variant H3.3 can be incorporated in chromatin independently of DNA synthesis. By imaging using green fluorescent protein-tagged histones, H3.