University of Palermo

About: University of Palermo is a education organization based out in Palermo, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 15621 authors who have published 40250 publications receiving 964384 citations. The organization is also known as: Università degli Studi di Palermo & Universita degli Studi di Palermo.

Levy Flight Superdiffusion: An Introduction

Abstract: After a short excursion from discovery of Brownian motion to the Richardson "law of four thirds" in turbulent diffusion, the article introduces the L\'{e}vy flight superdiffusion as a self-similar L\'{e}vy process. The condition of self-similarity converts the infinitely divisible characteristic function of the L\'{e}vy process into a stable characteristic function of the L\'{e}vy motion. The L\'{e}vy motion generalizes the Brownian motion on the base of the $\alpha$-stable distributions theory and fractional order derivatives. The further development of the idea lies on the generalization of the Langevin equation with a non-Gaussian white noise source and the use of functional approach. This leads to the Kolmogorov's equation for arbitrary Markovian processes. As particular case we obtain the fractional Fokker-Planck equation for L\'{e}vy flights. Some results concerning stationary probability distributions of L\'{e}vy motion in symmetric smooth monostable potentials, and a general expression to calculate the nonlinear relaxation time in barrier crossing problems are derived. Finally we discuss results on the same characteristics and barrier crossing problems with L\'{e}vy flights, recently obtained with different approaches.

Neoangiogenesis-related genes are hallmarks of fast-growing hepatocellular carcinomas and worst survival. Results from a prospective study

Abstract: Objective The biological heterogeneity of hepatocellular carcinoma (HCC) makes prognosis difficult. We translate the results of a genome-wide high-throughput analysis into a tool that accurately predicts at presentation tumour growth and survival of patients with HCC. Design Ultrasound surveillance identified HCC in 78 (training set) and 54 (validation set) consecutive patients with cirrhosis. Patients underwent two CT scans 6 weeks apart (no treatment in-between) to determine tumour volumes (V 0 and V 1 ) and calculate HCC doubling time. Baseline-paired HCC and surrounding tissue biopsies for microarray study (Agilent Whole Human Genome Oligo Microarrays) were also obtained. Predictors of survival were assessed by multivariate Cox model. Results Calculated tumour doubling times ranged from 30 to 621 days (mean, 107±91 days; median, 83 days) and were divided into quartiles: ≤53 days (n=19), 54–82 days (n=20), 83–110 days (n=20) and ≥111 days (n=19). Median survival according to doubling time was significantly lower for the first quartile versus the others (11 vs 41 months, 42, and 47 months, respectively) (p ANGPT2 ), delta-like ligand 4 ( DLL4 ), neuropilin (NRP)/tolloid (TLL)-like 2 ( NETO2 ), endothelial cell-specific molecule-1 ( ESM1 ), and nuclear receptor subfamily 4, group A, member 1 ( NR4A1 ) was found to accurately identify rapidly growing HCCs of the first quartile (ROC AUC: 0.961; 95% CI 0.919 to 1.000; p Conclusions The hepatic five-gene signature was able to predict HCC growth in individual patient and the consequent risk of death. This implies a role of this molecular tool in the future therapeutic management of patients with HCC. Trial registration number ClinicalTrials.gov Identifier: NCT01657695.

How Decarbonization, Digitalization and Decentralization are changing key power infrastructures

Abstract: This paper addresses the impact over key power infrastructures of the three main drivers for change of these times: Decarbonization, Digitalization and Decentralization. The three phenomena, according to prominent observers, are affecting all fields of our lives but, in the literature, it is difficult to find an analysis of their impact on electrical power systems. The framework proposed in this paper, based on the main power systems evolution models proposed by CIGRE, uses data from open databases and tries to find out general guidelines for power systems development at a worldwide level. Taking as reference the European and COP21 environmental objectives and beyond, the technological evolution of some key enabling technologies is explored. What emerges is that HV bulk transport links, storage technologies and the so-called digital revolution are taking a leading role in different parts of the world for the development of a deep decarbonization of the electricity sector, of new energy business models at distribution level and of new power distribution architectures.