We review the properties and nature of luminous high-redshift radio galaxies (HzRGs, z > 2) and the environments in which they are located. HzRGs have several distinct constituents which interact with each other relativistic plasma, gas in various forms, dust, stars and an active galactic nucleus (AGN). These building blocks provide unique diagnostics about conditions in the early Universe. We ...

The Industrial Ecology (IE) is a new interdisciplinary field focused on sustainable development. IE aims to the shifting of industrial processes from open-loop systems where different resources move through a system to become wastes to a closed-loop system where wastes become inputs for new processes. This paper introduces a Green Virtual Enterprise (GVE) model as an emerging sustainable manufa...

Many of the powerful radio galaxies observed at high redshift are very small, presumably because they are very young. A simple model, which treats the radio source as a bubble expanding into a radially stratified medium, is capable of explaining the main features of their size and luminosity evolution. In particular, the model predicts strong negative luminosity evolution with increasing size, ...

We make use of the first high–resolution hydrodynamic simulations of structure formation which self-consistently follows the build up of supermassive black holes introduced in Di Matteo et al. (2007) to investigate the relation between black holes (BH), host halo and large–scale environment. There are well–defined relations between halo and black hole masses and between the activities of galact...

We use a 3D Monte Carlo radiative transfer code to study the projection of large shadows by circumstellar disks around young stellar objects on surrounding reflection nebulosity. It is shown that for a wide range of parameters a small (10−100 AU) circumstellar disk can project a large (1000−10 000 AU) dark band in the near-infrared that often resembles a massive edge-on disk. The disk shadows a...