A new nonparametric approach to galaxy morphological classification

We present two new nonparametric methods for quantifying galaxy morphology: the relative distribution of the galaxy pixel flux values (the Gini coefficient or G) and the second-order moment of the brightest 20% of the galaxy's flux (M 20). We test the robustness of G and M 20 to decreasing signal-to-noise ratio (S/N) and spatial resolution and find that both measures are reliable to within 10% for images with average S/N per pixel greater than 2 and resolutions better than 1000 and 500 pc, re...

Early metal enrichment of the intergalactic medium by pregalactic outflows

We assess supernova-driven pregalactic outflows as a mechanism for distributing the product of stellar nucleosynthesis over large cosmological volumes prior to the reionization epoch. Supernova (SN) ejecta will escape the grasp of halos with virial temperatures Tvir ≥ 104.3 K (corresponding to masses M ≥ 108 h-1 M⊙ at redshift z = 9 when they collapse from 2 σ fluctuations) if rapid cooling can take place, and a significant fraction of their baryonic mass is converted into stars over a dynami...

Analysis of implant precision in guided surgery: comparison of two methods

Background: Implantology represents the therapy of choice for the rehabilitation of a partially or totally edentulous jaw in a healthy patient. Nowadays, it is possible to exploit of modern preoperative planning software, increasingly precise radiographic examinations (CBCT) and CAD/CAM technologies that allow designing devices directly on the computer to be sent to a milling center which produces the desired product, such as stereolithographic templates. Methods: The prospective clinical ...

Cultura visiva digitale e femminismo iconico