http://physicsweb.org/articles/news/11/1/12/1
There has been an ongoing effort to find out if gravity follows Newtonian physics on very small scales, any deviation would point to
"interferance" from other dimensions. The previous measurement was done on a scale of one tenth of a millimeter (100 microns) with no deviation from Newton. Now that has extended by a factor of 2, 55 microns and with a confidence of 95% showing no extra dimensions at that scale. Work continues on smaller scales.