Black holes binaries coming from a distribution of primordial black might exhibit large merger rate up to redshifts. Using phenomenological model for the rate, we show that changes in its slope, redshifts $z\sim 4$, are constrained by current limits on amplitude stochastic gravitational wave background LIGO/Virgo O3 run. This shows constrains larger than single event horizon detection ($z\simeq...

In this paper we propose a novel hybrid multispectral MR images segmentation framework which combines Markov Random Field (MRF), stochastic relaxation (SR) scheme and an improved Genetic Algorithm (IGA). MRF models have by now been firmly established as a robust tool for de-noising and segmentation of medical images. Characterizing MRFs by their local properties (Markovianity), they are well su...