Self-organized criticality in a model of collective bank bankruptcies

The question we address here is of whether phenomena of collective bankruptcies are related to self-organized criticality. In order to answer it we propose a simple model of banking networks based on the random directed percolation. We study effects of one bank failure on the nucleation of contagion phase in a financial market. We recognize the power law distribution of contagion sizes in 3d- and 4d-networks as an indicator of SOC behavior. The SOC dynamics was not detected in 2d-lattices. The difference between 2d- and 3d- or 4d-systems is explained due to the percolation theory.Comment: For Int. J. Mod. Phys. C 13, No. 3, six pages including four figure

A met\ue0 del traguardo nell'anno della biodiversit\ue0

La biodiversit\ue0, oltre a essere una ricchezza per la natura in quanto tale, \ue8 la risorsa principale di intere popolazioni che dipendono dalle risorse biologiche per il nutrimento, la cura della salute, l\u2019energia, i vestiti e le abitazioni. L\u2019affermazione di nuovi sistemi di propriet\ue0 intellettuale e lo sfruttamento intensivo della biodiversit\ue0 determina una nuova forma di conflitto tra propriet\ue0 privata e propriet\ue0 comunitaria, tra uso locale e uso sfruttamento globale. La biodiversit\ue0 \ue8 cruciale in quanto garantisce all\u2019uomo il supporto per la vit

Identification of a Widespread Palmitoylethanolamide Contamination in Standard Laboratory Glassware.

Introduction: Fatty acid ethanolamides (FAEs) are a family of lipid mediators that participate in a host of biological functions. Procedures for the quantitative analysis of FAEs include organic solvent extraction from biological matrices (e.g., blood), followed by purification and subsequent quantitation by liquid chromatography-mass spectrometry (LC/MS) or gas chromatography-mass spectrometry. During the validation process of a new method for LC/MS analysis of FAEs in biological samples, we observed unusually high levels of the FAE, palmitoylethanolamide (PEA), in blank samples that did not contain any biological material. Materials and Methods: We investigated a possible source of this PEA artifact via liquid chromatography coupled to tandem mass spectrometry, as well as accurate mass analysis. Results: We found that high levels of a contaminant indistinguishable from PEA is present in new 5.75″ glass Pasteur pipettes, which are routinely used by laboratories to carry out lipid extractions. This artifact might account for discrepancies found in the literature regarding PEA levels in human blood serum and other tissues. Conclusions: It is recommended to take into account this pitfall by analyzing potential contamination of the disposable glassware during the validation process of any method used for analysis of FAEs

Optimization of an axial fan for air cooled condensers

We report on the low noise optimization of an axial fan specifically designed for the cooling of CSP power plants. The duty point presents an uncommon combination of a load coefficient of 0.11, a flow coefficient of 0.23 and a static efficiency ηstat > 0.6. Calculated fan Reynolds number is equal to Re = 2.85 x 107. Here we present a process used to optimize and numerically verify the fan performance. The optimization of the blade was carried out with a Python code through a brute-force-search algorithm. Using this approach the chord and pitch distributions of the original blade are varied under geometrical constraints, generating a population of over 24000 different possible individuals. Each individual was then tested using an axisymmetric Python code. The software is based on a blade element axisymmetric principle whereby the rotor blade is divided into a number of streamlines. For each of these streamlines, relationships for velocity and pressure are derived from conservation laws for mass, tangential momentum and energy of incompressible flows. The final geometry was eventually chosen among the individuals with the maximum efficiency. The final design performance was then validated through with a CFD simulation. The simulation was carried out using a RANS approach, with the cubic k -  low Reynolds turbulence closure of Lien et al. The numerical simulation was able to verify the air performance of the fan and was used to derive blade-to-blade distributions of design parameters such as flow deviation, velocity components, specific work and diffusion factor of the optimized blade. All the computations were performed in OpenFoam, an open source C++- based CFD library. This work was carried out under MinWaterCSP project, funded by EU H2020 programme

Il sole: l'unica fonte di energia "nucleare" in grado di combattere i cambiamenti climatici. Il caso di Montalto di Castro, dal nucleare al solare

Negli ultimi decenni si è assistito a un costante aumento del fabbisogno energetico sia a livello nazionale sia internazionale. La grandissima quantità di consumi energetici prodotti da fonti fossili, la deforestazione, l’’agricoltura monoculturale industrializzata e la zootecnia hanno accresciuto le emissioni dei gas serra in atmosfera, in particolare l’anidride carbonica (CO2), il metano (CH4), e altri gas climalteranti, innalzando la soglia del rischio ambientale e l’equilibrio termodinamico del Pianeta. Le proiezioni dei modelli climatici basati su differenti scenari di emissioni future di gas serra indicano che l’aumento della temperatura entro la fine del secolo (Metz et al., 2007) potrebbe causare un significativo impatto sul ciclo idrologico. Con temperature mediamente più alte aumenterà l’evaporazione e l’intensità del ciclo dell’acqua, con un conseguente accrescimento dell’umidità dell’aria. La magnitudine e la frequenza di eventi estremi, come inondazioni e siccità, probabilmente saranno più frequenti e severe anche in Europa. Questi fenomeni, insieme all’incremento della richiesta di acqua, sia in ambito agricolo sia da parte di altri settori, renderanno l’Europa più vulnerabile alla siccità (Facts about climate change, 2009). Per tale ragione i cambiamenti climatici sono diventati un argomento centrale nei programmi di Ricerca e Sviluppo dell’Unione Europea

Laser scanning e photo scanning. Tecniche di rilevamento per la documentazione 3D di beni architettonici ed archeologici

Laser scanner and digital photogrammetric systems (photo scanning) must be considered at present two of the main techniques used for archaeological and architectural surveying. The integration of both 3D scanning systems allowed us to improve the scientific knowledge, the management, the use and the safeguarding of Cultural Heritage. The aim of this article is to identify analogies and differences between the two surveying techniques applied to different archaeological contexts. Starting from a general introduction to the concept of measurement and the management of the data acquired from different techniques of surveying, the article focuses on the laser scanner applications with particular attention on the intrinsic properties of the instrument, the problems of measurement and the methodology used during the survey. The second part is focused on the digital photogrammetry applied on a particular archaeological context. Digital photogrammetry was developed and experimented in order to acquire territorial data quickly. The optimization of the working speed, while maintaining accuracy of data, means cost savings and an optimal use of funds. Our workgroup decided to transfer that methodology to the archaeological excavations of Rome Metro Line C in collaboration with some public institutions and private companies. The final results have produced 2D and 3D graphic documentations of all the archaeological area up to highly-accurate ortho-recti ??ed images. Point clouds allowed us to simultaneously view a general 3D model of all open archaeological areas, providing an opportunity for observation and an analysis not possible by other means. Each area can be studied together with the others in a global view of the excavation. Every stratigraphic unit can be displayed in the same area and switched on in the same way as a layer