Constraints on a scale-dependent bias from galaxy clustering

We forecast the future constraints on scale-dependent parametrizations of galaxy bias and their impact on the estimate of cosmological parameters from the power spectrum of galaxies measured in a spectroscopic redshift survey. For the latter we assume a wide survey at relatively large redshifts, similar to the planned Euclid survey, as baseline for future experiments. To assess the impact of the bias we perform a Fisher matrix analysis and we adopt two different parametrizations of scale-dependent bias. The fiducial models for galaxy bias are calibrated using a mock catalogs of H$\alpha$ emitting galaxies mimicking the expected properties of the objects that will be targeted by the Euclid survey. In our analysis we have obtained two main results. First of all, allowing for a scale-dependent bias does not significantly increase the errors on the other cosmological parameters apart from the rms amplitude of density fluctuations, $\sigma_{8}$, and the growth index $\gamma$, whose uncertainties increase by a factor up to two, depending on the bias model adopted. Second, we find that the accuracy in the linear bias parameter $b_{0}$ can be estimated to within 1-2\% at various redshifts regardless of the fiducial model. The non-linear bias parameters have significantly large errors that depend on the model adopted. Despite of this, in the more realistic scenarios departures from the simple linear bias prescription can be detected with a $\sim2\,\sigma$ significance at each redshift explored. Finally, we use the Fisher Matrix formalism to assess the impact of assuming an incorrect bias model and found that the systematic errors induced on the cosmological parameters are similar or even larger than the statistical ones.Comment: new section added; conclusions unchanged; accepted for publication in PR

Paolo Sylos Labini: Reflections of a Classical Economist

The article provides a review of Sylos Labini’s memories, collected here on occasion of the tenth anniversary of his passing away. The author reports on the proceedings of two conferences in memory of Sylos Labini held in Rome, on 18 November 2015 at the Lincean Academy and on 4 December 2015 at Sapienza University. Sylos Labini stipulated that the goal of economic development is not just to satisfy human needs, but to cater civil development itself, in accordance with Adam Smith’s fundamental lesson. In his view, economic development and civil development interact in a circular manner in the long run. Considering the developmental issues of Italy’s Mezzogiorno, Sylos Labini highlights that the nature of the problem is not only economic, but rather many issues arise from unreasonable links between politics, economy, and society. Accordingly, he provided policy suggestions that are not limited to the economic and industrial fields (such as water supply projects, irrigation infrastructures, and investments for the creation of modern industries), but he also identified three priority areas of social policy: measures to contrast the mafias, crime in public procurement, and corruption; a reform of the public administration; and investments in education, universities, and research

Editorial: Paolo Sylos Labini (1920-2005)

The article introduces to the new issue of the Review, which roughly corresponds with the tenth anniversary of the passing away of Paolo Sylos Labini (PSL). As explained by Roncaglia (2008), the very name of the PSL Quarterly Review is dedicated to the Italian economist, due among other things to the long run relation between PSL and the old series of this journal. The paper discusses PSL’s contributions in the Banca Nazionale del Lavoro Quarterly Review, focusing on his forecast of the recent global crisis, published in 2003. This contribution already contained precise reference – often backed by data for the USA and other economies – to trends and ‘explanations’ of the crisis that several mainstream economists (e.g. Robert Lucas) claimed were impossible to see before the crisis itself. These include the accumulation of excessive household debt, excessive complacency on the side of the Fed, speculative bubbles in the US stock exchange and real estate markets, and the deflationary pressures caused by radical technological innovations. PSL’s example shows that the economists can and often do provide useful services to society, provided they build on solid theories

A Meta-Heuristic Optimization Procedure for the Identification of the Nonlinear Model Parameters of Hydraulic Dampers Based on Experimental Dataset of Real Working Conditions

Hydralic dampers are widely implemented in railway vehicle suspension stages, especially in high-speed passenger trains. They are designed to be mounted in different positions to improve comfort, stability, and safety performances. Numerical simulations are often used to assist the design and optimization of these components. Unfortunately, hydraulic dampers are highly nonlinear due to the complex fluid dynamic phenomena taking place inside the chambers and through the by-pass orifices. This requires accurate damper models to be developed to estimate the influence of the nonlinearities of such components during the dynamic performances of the whole vehicle. This work aims at presenting a new parametric damper model based on a nonlinear lumped element approach. Moreover, a new model tuning procedure will be introduced. Differently from the typical sinusoidal characterization cycles, this routine is based on experimental tests of real working conditions. The set of optimal model parameters will be found through a metaheuristic iterative approach able to minimize the differences between numerical and experimental damper forces. The performances of the optimal model will be compared with the ones of the most common Maxwell model generally implemented in railway multibody software programs

Recuperação de pastagens degradadas para sistemas intensivos de produção de bovinos.

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Sulodexide counteracts endothelial dysfunction induced by metabolic or non-metabolic stresses through activation of the autophagic program

OBJECTIVE: Endothelial dysfunction (ED) predisposes to venous thrombosis (VT) and post-thrombotic syndrome (PTS), a long-term VT-related complication. Sulodexide (SDX) is a highly purified glycosaminoglycan with antithrombotic, pro-fibrinolytic and anti-inflammatory activity used in the treatment of chronic venous disease (CVD), including patients with PTS. SDX has recently obtained clinical evidence in the “extension therapy” after initial-standard anticoagulant treatment for the secondary prevention of recurrent deep vein thrombosis (DVT). Herein, we investigated how SDX counteracts ED. MATERIALS AND METHODS: Human umbilical vein endothelial cells (HUVEC) were used. Metabolic and non metabolic-induced ED was induced by treating with methylglyoxal (MGO) or irradiation (IR), respectively. Bafilomycin A1 was used to inhibit autophagy. The production of reactive oxygen species (ROS), tetrazolium bromide (MTT) assay for cell viability, terminal de-oxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay for cell apoptosis, Real-time PCR and Western blot analysis for gene and protein expression were used. RESULTS: SDX protected HUVEC from MGO- or IR-induced apoptosis by counteracting the activation of the intrinsic and extrinsic caspase cascades. The cytoprotective effects of SDX resulted from a reduction in a) ROS production, b) neo-synthesis and release of pro-inflammatory cytokines (TNFα, IL1, IL6, IL8), c) DNA damage induced by MGO or IR. These effects were reduced when autophagy was inhibited. CONCLUSIONS: Data herein collected indicate the ability of SDX to counteract ED induced by metabolic or non-metabolic stresses by involving the intracellular autophagy pathway. Our experience significantly increases the knowledge of the mechanisms of action of SDX against ED and supports the use of SDX in the treatment of CVD, PTS and in the secondary prevention of recurrent DVT