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Rome, Italy

The Sapienza University of Rome, officially Sapienza – Università di Roma, also called simply Sapienza formerly known as Università degli studi di Roma "La Sapienza", is a coeducational, autonomous state university in Rome, Italy. It is the largest European university by enrollments and the oldest of Rome's four state universities, founded in 1303. In Italian, sapienza means "wisdom" or "knowledge".Being the biggest Italian University, Sapienza is member of several national and international groups, as: European Spatial Development Planning, Partnership of a European Group of Aeronautics and Space Universities, CINECA, Santander Network, Institutional Network of the Universities from the Capitals of Europe, Mediterranean Universities Union.Sapienza is present in all major international university rankings. It is among the best Italian universities.According to the Academic Ranking of World Universities compiled by the Jiao Tong University of Shanghai, Sapienza is regularly ranked first among Italian universities. Sapienza is positioned within the 101-150 group of universities and among the top 3% of universities in the world.According to webometrics.info La Sapienza is #8th in Europe and #1 in Italy.In 2013, the Center for World University Rankings ranked the Sapienza University of Rome 62nd in the world and the top in Italy in its World University Rankings.According to the American society "U.S News & World Report", La Sapienza is the most prestigious Italian University Wikipedia.

Pirozzoli S.,University of Rome La Sapienza
Annual Review of Fluid Mechanics | Year: 2011

We review numerical methods for direct numerical simulation (DNS) and large-eddy simulation (LES) of turbulent compressible flow in the presence of shock waves. Ideal numerical methods should be accurate and free from numerical dissipation in smooth parts of the flow, and at the same time they must robustly capture shock waves without significant Gibbs ringing, which may lead to nonlinear instability. Adapting to these conflicting goals leads to the design of strongly nonlinear numerical schemes that depend on the geometrical properties of the solution. For low-dissipation methods for smooth flows, numerical stability can be based on physical conservation principles for kinetic energy and/or entropy. Shock-capturing requires the addition of artificial dissipation, in more or less explicit form, as a surrogate for physical viscosity, to obtain nonoscillatory transitions. Methods suitable for both smooth and shocked flows are discussed, and the potential for hybridization is highlighted. Examples of the application of advanced algorithms to DNS/LES of turbulent, compressible flows are presented. © 2011 by Annual Reviews. All rights reserved. Source

Bianco P.,University of Rome La Sapienza
Annual review of cell and developmental biology | Year: 2014

Two opposing descriptions of so-called mesenchymal stem cells (MSCs) exist at this time. One sees MSCs as the postnatal, self-renewing, and multipotent stem cells for the skeleton. This cell coincides with a specific type of bone marrow perivascular cell. In skeletal physiology, this skeletal stem cell is pivotal to the growth and lifelong turnover of bone and to its native regeneration capacity. In hematopoietic physiology, its role as a key player in maintaining hematopoietic stem cells in their niche and in regulating the hematopoietic microenvironment is emerging. In the alternative description, MSCs are ubiquitous in connective tissues and are defined by in vitro characteristics and by their use in therapy, which rests on their ability to modulate the function of host tissues rather than on stem cell properties. Here, I discuss how the two views developed, conceptually and experimentally, and attempt to clarify the confusion arising from their collision. Source

Bianco P.,University of Rome La Sapienza
Blood | Year: 2011

The revived interest in (hematopoietic) stem cell (HSC) niches has highlighted the role of multiple cellular players found in the bone environment. Initially focused on the role of osteoblasts and sinusoid endothelial cells, the quest for HSC niche cells has recently focused on a unique role for osteoprogenitor cells (skeletal stem cells, mesenchymal stem cells). Strongly validated by observations of HSC dysregulation dictated by the dysregulation of osteoprogenitors, the role of osteoprogenitors in the HSC niche integrates data from different studies into a unified view. As preosteoblastic, periendothelial cells residing at the sinusoid wall, skeletal progenitors reconcile the notions of "osteoblastic" and "sinusoidal" niches with one another. In addition, they bring into focus the cross-regulation of skeletal and hematopoietic physiology as rooted into the interplay of two stem cells (hematopoietic and skeletal) sharing a single niche. As direct regulators of hematopoietic space formation, sinusoid development, and hematopoietic function(s), as well as direct progenitors of positive and negative regulators of HSCs such as osteoblasts and adipocytes, skeletal progenitors have emerged as pivotal organizers of a complex, highly plastic niche. This development seems to represents an evolutionary advance over the deterministic stem cell niches found in archetypal invertebrate systems. © 2011 by The American Society of Hematology. Source

Parisi G.,University of Rome La Sapienza | Zamponi F.,Laboratoire Of Physique Theorique
Reviews of Modern Physics | Year: 2010

Hard spheres are ubiquitous in condensed matter: they have been used as models for liquids, crystals, colloidal systems, granular systems, and powders. Packings of hard spheres are of even wider interest as they are related to important problems in information theory, such as digitalization of signals, error correcting codes, and optimization problems. In three dimensions the densest packing of identical hard spheres has been proven to be the fcc lattice, and it is conjectured that the closest packing is ordered (a regular lattice, e.g., a crystal) in low enough dimension. Still, amorphous packings have attracted much interest because for polydisperse colloids and granular materials the crystalline state is not obtained in experiments for kinetic reasons. A theory of amorphous packings, and more generally glassy states, of hard spheres is reviewed here, that is based on the replica method: this theory gives predictions on the structure and thermodynamics of these states. In dimensions between two and six these predictions can be successfully compared with numerical simulations. The limit of large dimension is also discussed where an exact solution is possible. Some of the results presented here were published, but others are original: in particular, an improved discussion of the large dimension limit and new results on the correlation function and the contact force distribution in three dimensions. The main assumptions that are beyond the theory presented are clarified and, in particular, the relation between static computation and the dynamical procedures used to construct amorphous packings. There remain many weak points in the theory that should be better investigated. © 2010 The American Physical Society. Source

Amelino-Camelia G.,University of Rome La Sapienza
Living Reviews in Relativity | Year: 2013

I review the current status of phenomenological programs inspired by quantum-spacetime research. I stress in particular the significance of results establishing that certain data analyses provide sensitivity to effects introduced genuinely at the Planck scale. My main focus is on phenomenological programs that affect the directions taken by studies of quantum-spacetime theories. Source

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