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We examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance CDM cosmology. Strong deviations are allowed by the data at z 1 in the reconstructed Hubble parameter, Om diagnostic, and dark energy equation of state. We explore three interpretations: 1) possibility of the true cosmology being far from CDM, 2) supernovae property evolution, and 3) survey selection effects. The strong (and theoretically problematic) deviations at z 1 vanish and good consistency with CDM is found with a simple Malmquist-like linear correction. The adjusted data is robust against the model independent iterative smoothing reconstruction. However, we caution that while by eye the original deviation from CDM is striking, χ2 tests do not show the extra linear correction parameter is statistically significant, and a model-independent Gaussian Process regression does not find significant evidence for the need for correction at high-redshifts.

Galaxies accrete their mass by means of both smooth accretion from the cosmic web, and the mergers of smaller entities. We wish to quantify the respective role of these two modes of accretion, which could determine the morphological types of galaxies observed today. Multi-zoom cosmological simulations are used to estimate as a function of time the evolution of mass in bound systems, for dark matter as well as baryons. The baryonic contents of dark matter haloes are studied. Merger histories are followed as a function of external density, and the different ways in which mass is assembled in galaxies and the stellar component accumulated are quantified. We find that most galaxies assemble their mass through smooth accretion, and only the most massive galaxies also grow significantly through mergers. The mean fraction of mass assembled by accretion is 77%, and by mergers 23%. We present typical accretion histories of hundreds of galaxies: masses of the most massive galaxies increase monotonically in time, mainly through accretion, many intermediate-mass objects also experience mass-loss events such as tidal stripping and evaporation. However, our simulations suffer from the overcooling of massive galaxies caused by the neglect of active galaxy nuclei (AGN) feedback. The time by which half of the galay mass has assembled, both in dark matter and baryons, is a decreasing function of mass, which is compatible with the observations of a so-called downsizing. At every epoch in the universe, there are low-mass galaxies actively forming stars, while more massive galaxies form their stars over a shorter period of time within half the age of the universe. [ABSTRACT FROM AUTHOR]

Between February 1983 and June 1994 we attempted surgically to salvage twenty-six legs in twenty-five patients with insufficient distal run-off and severely ischemic feet; all of them had resting pain, and 23 had tissue necrosis. A saphenous venous graft was interposed between an artery of the lower extremity (femoral or popliteal) and the veins of the foot with obligatory end-to-side distal anastomosis. The patency of the venous circulation of the ischemic foot was ascertained by retrograde phlebography. Patients were followed from 3 months to 11 years (an average of 3 years and 5 months). In 19 legs (73%), surgery succeeded in preventing extensive gangrene of the foot, and allowed postponing or avoiding major amputation. The purpose of this paper is to analyze this experience, and stimulate further interest and study of the reversed microcirculation in critical ischemia.