Levosimendan in Sepsis.

Commentum to "Levosimendan for the Prevention of Acute Organ Dysfunction in Sepsis

Long time behavior of quasi-stationary states of the Hamiltonian Mean-Field model

The Hamiltonian Mean-Field model has been investigated, since its introduction about a decade ago, to study the equilibrium and dynamical properties of long-range interacting systems. Here we study the long-time behavior of long-lived, out-of-equilibrium, quasi-stationary dynamical states, whose lifetime diverges in the thermodynamic limit. The nature of these states has been the object of a lively debate, in the recent past. We introduce a new numerical tool, based on the fluctuations of the phase of the instantaneous magnetization of the system. Using this tool, we study the quasi-stationary states that arise when the system is started from different classes of initial conditions, showing that the new observable can be exploited to compute the lifetime of these states. We also show that quasi-stationary states are present not only below, but also above the critical temperature of the second order magnetic phase transition of the model. We find that at supercritical temperatures the lifetime is much larger than at subcritical temperatures.Comment: Submitted to Phys. Rev.

Low Complexity WMMSE Power Allocation In NOMA-FD Systems

In this paper we study the problem of power and channel allocation with the objective of maximizing the system sum-rate for multicarrier non-orthogonal multiple access (NOMA) full duplex (FD) systems. Such an allocation problem is non-convex and, thus, with the goal of designing a low complexity solution, we propose a scheme based on the minimization of the weighted mean square error, which achieves performance reasonably close to the optimum and allows to clearly outperforms a conventional orthogonal multiple access approach. Numerical results assess the effectiveness of our algorithm.Comment: 5 pages conference paper, 3 figures. Submitted on ICASSP 202

Additive Manufacturing of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/poly(ε-caprolactone) Blend Scaffolds for Tissue Engineering

Additive manufacturing of scaffolds made of a polyhydroxyalkanoate blended with another biocompatible polymer represents a cost-effective strategy for combining the advantages of the two blend components in order to develop tailored tissue engineering approaches. The aim of this study was the development of novel poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/ poly("-caprolactone) (PHBHHx/PCL) blend scaffolds for tissue engineering by means of computer-aided wet-spinning, a hybrid additive manufacturing technique suitable for processing polyhydroxyalkanoates dissolved in organic solvents. The experimental conditions for processing tetrahydrofuran solutions containing the two polymers at different concentrations (PHBHHx/PCL weight ratio of 3:1, 2:1 or 1:1) were optimized in order to manufacture scaffolds with predefined geometry and internal porous architecture. PHBHHx/PCL scaffolds with a 3D interconnected network of macropores and a local microporosity of the polymeric matrix, as a consequence of the phase inversion process governing material solidification, were successfully fabricated. As shown by scanning electron microscopy, thermogravimetric, differential scanning calorimetric and uniaxial compressive analyses, blend composition significantly influenced the scaffold morphological, thermal and mechanical properties. In vitro biological characterization showed that the developed scaffolds were able to sustain the adhesion and proliferation of MC3T3-E1 murine preosteoblast cells. The additive manufacturing approach developed in this study, based on a polymeric solution processing method avoiding possible material degradation related to thermal treatments, could represent a powerful tool for the development of customized PHBHHx-based blend scaffolds for tissue engineering

SEISMIC RETROFIT OF AN INDUSTRIAL STRUCTURE THROUGH AN INNOVATIVE SELF-CENTERING HYSTERETIC DAMPER: MODELLING, ANALYSIS AND OPTIMIZATION.

Recent earthquakes, as the one that hit Fukushima in Japan in 2011 or the one that produced extensive damage in Turkish petrochemical facilities during the Kocaeli earthquake of 1999 or, more recently, the seismic events in May 2012 in Emilia (Italy), highlighted the increasing need of providing adequate protection to industrial installations. Industrial facilities often store a large amount of hazardous material and, in case of seismic event, there is a high probability that accidental scenarios as fire, explosion, toxic or radioactive dispersion may occur. In these cases, the ensuing disaster certainly harms the people working in the installation and it may endanger the population living in the neighborhood or in the urban area where the industrial installation is located. The consequences of such accidental scenarios can be disastrous in terms of casualties, economic losses and environmental damage. Within this work, the seismic behavior of an industrial structure is studied through several Incremental Dynamic Analyses, IDA, and particular attention is given to the selection of suitable performance criteria and the modelling of non linear phenomena (II order effects, buckling, mechanical non-linearity, etc.). The seismic behavior is then enhanced applying to the structure an innovative typology of self-centering hysteretic damper, whose mechanical characteristics are optimized through the execution of IDAs on the retrofitted structures. A final comparison between the seismic behavior of the original structure and of the retrofitted one highlights the advantages of the innovative self-centering hysteretic dampers

Effects of the representation of the crustal structure on seismic wave propagation modeling on the continental scal

The representation of crustal structure in 3D numerical models often poses particular problems that are difficult to overcome. Practical implementations of an improved crustal model into efficient tools for seismic wave propagation modeling often fail to honor the strongly varying depth of the Moho discontinuity. The widely used Spectral Element Method (SEM) using hexahedral elements follows the compromise to approximate this undulating discontinuity with polynomials inside the elements. This solution is satisfactory when modeling seismic wave propagation on the global scale and limitedly to rather low frequencies, but may induce inaccuracies or artifacts when working at the continental scale, where propagation distances are in the order of a few hundred or thousand kilometers and frequencies of interest are up to 0.1 Hz. An alternative modeling tool for seismic wave propagation simulations is the Discontinuous Galerkin Finite Element Method (ADER-DG) that achieves high-order accuracy in space and time using fully unstructured tetrahedral meshes. With this approach strong and undulating discontinuities can be considered more easily by the mesh and modifications of the geometrical properties can be carried out rapidly due to an external mesh generation process. Therefore, we implement more realistic models for the European crust -- based on a new, comprehensive compilation of currently available information from diverse sources, ranging from seismic prospection to receiver functions studies -- in both, the SEM and ADER-DG codes, to study the effects of the numerical representation of crustal structures on seismic wave propagation modeling. We compare the results of the different methods and implementation strategies with respect to accuracy and performance. Clearly, an improved knowledge and detailed representation of the structure of the Earth's crust is a key requisite for better imaging of the mantle structure

Affidabilità di laser sintonizzabili di tipo innovativo per applicazioni in sistemi di telecomunicazione

The demand for broadband services is expected to increase worldwide at an accelerated pace in the next future . To allow the mass introduction of the broadband access services, however, a number of technological barriers still need to be overcome, in particular, research is presently very active in the field of photonics, aimed at the development of a new generation of photonic devices based on nanotechnology. This should allow to solve in a cost-effective way the so called ‘metro bottleneck’, that is the congestion in the metropolitan access infrastructure, expected to arise for the increased traffic flowing from the access network. To the telecommunications ‘backbone’, and viceversa, due to increase of capacity demand from the customers, in order to be successful, innovative photonic products must of course satisfy a number of performance requirement, either economical and technical , and in particular they must be designed and manufactured in such away as to guarantee that the will operate reliably for as long a period as possible. The study reported in this thesis consists in the full reliability assessment of a new product designed and manufactured by Pirelli, that is a tunable laser of new conception, based on photonic nanotechnologies