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The aim of this study was to evaluate the effect of a time-dependent magnetic field on the biological performance of periodontal ligament stem cells (PDLSCs). A Western blot analysis and Alamar Blue assay were performed to investigate the proliferative capacity of magnetically stimulated PDLSCs (PDLSCs MAG) through the study of the MAPK cascade (p-ERK1/2). The observation of ALP levels allowed the evaluation of the effect of the magnetic field on osteogenic differentiation. Metabolomics data, such as oxygen consumption rate (OCR), extracellular acidification rate (ECAR) and ATP production provided an overview of the PDLSCs MAG metabolic state. Moreover, the mitochondrial state was investigated through confocal laser scanning microscopy. Results showed a good viability for PDLSCs MAG. Magnetic stimulation can activate the ERK phosphorylation more than the FGF factor alone by promoting a better cell proliferation. Osteogenic differentiation was more effectively induced by magnetic stimulation. The metabolic panel indicated significant changes in the mitochondrial cellular respiration of PDLSCs MAG. The results suggested that periodontal ligament stem cells (PDLSCs) can respond to biophysical stimuli such as a time-dependent magnetic field, which is able to induce changes in cell proliferation and differentiation. Moreover, the magnetic stimulation also produced an effect on the cell metabolic profile. Therefore, the current study demonstrated that a time-dependent magnetic stimulation may improve the regenerative properties of PDLSCs.

A simplified Fusion-Fission Hybrid System (FFHS) deterministic calculation model has been developed in order to study the coupling be- tween a fusion machine and a subcritical fission system. Monte-Carlo (MC) codes are very flexible and they have to be considered as refer- ence calculation tools for complex systems like FFHS. On the other hand, deterministic codes can provide, in shorter calculation time respect to MC codes, parametric and sensitivity analysis, also by exploiting General Perturbation Theory (GPT) methodologies, which can usefully support the global FFHS theoretical analysis. This work describes the comparison between the results obtained for a simplified FFHS model by using a MC code (MCNP6.1, MC N-Particle) and a deterministic code (ERANOS). In particular, in this preliminary study, integral pa- rameters like keff, thermal power, neutron fluxes and some key reaction rate profiles, will be compared. If the comparison between the two mentioned codes will give encouraging results further, more refined, studies will be performed in order to consider deterministic codes as a powerful workhorse for the FFHS analysis, including time dependent analysis devoted to transient and reactivity monitoring issues.

Medical applications stimulate the need for materials with broad potential. Chitosan, the partially deacetylated derivative of chitin, offers many interesting characteristics, such as biocompatibility and chemical derivatization possibility. In the present study, porous scaffolds composed of electrospun interwoven nanometric fibers are produced using chitosan or chitosan functionalized with aliphatic chains of twelve, fourteen or sixteen methylene groups. The scaffolds were thoroughly characterized by SEM and XPS. The length of the aliphatic tail influenced the physico-chemical and dynamic mechanical properties of the functionalized chitosan. The electrospun membranes revealed no interaction of Gram+ or Gram− bacteria, resulting in neither antibacterial nor bactericidal, but constitutively sterile. The electrospun scaffolds demonstrated the absence of cytotoxicity, inflammation response, and eryptosis. These results open the door to their application for blood purification devices, hemodialysis membranes, and vascular grafts.

Based on the heuristically generalized perturbation theory (HGPT) adapted to subcritical systems [1], a procedure for online operational monitoring of the subcriticality level of a hybrid fusion-fission system in which an “external” neutron source is generated in a magnetically confined tokamak-type plasma is described. This procedure [2], commonly referred to as power control-based subcriticality monitoring (PCSM), consists of compensating of slow and small movements of a specialized control rod in the nuclear fission zone, previously calibrated using a standard procedure, with equally slow and small alterations of the fusion neutron source. PCSM is verified by solving the multi-group transport equation for the direct flux, as well as for the importance function, associated with normalized fission power [3], and a technique is proposed for modifying the fusion neutron source strength based on plasma compression/expansion. Plasma and confining magnetic field adjustments, needed to implement the PCSM, are estimated with due account of the 0-D-plasma power balance.

Il Trattato di Maastricht ha trapiantato nel patto costitutivo delle società europee il principio della delega del governo della moneta a un’istituzione irresponsabile di fronte agli organismi rappresentativi dei titolari della sovranità, e lo ha legittimato agli occhi dell’opinione pubblica con l’argomento secondo cui la politica monetaria sarebbe incapace di incidere sulla distribuzione della ricchezza tra le diverse categorie di operatori che contribuiscono alla produzione. Nel saggio, l’idea della neutralità del governo della moneta viene discussa criticamente alla luce di una ricognizione della letteratura di matrice eterodossa e di una ricostruzione storica della vicenda della BCE. Si sostiene che i poteri attribuiti all’autorità monetaria europea dal Trattato di Maastricht siano stati sistematicamente utilizzati per mantenere l’economia sotto una soffocante cappa deflazionistica, con l’obiettivo di indebolire il potere negoziale delle organizzazioni rappresentative del lavoro dipendente, in modo da disciplinare severamente la dinamica salariale. Sebbene negli anni della crisi si sia consolidata una narrazione del ruolo della BCE come principale attore di contrasto alla recessione, tale “lettura” non risulta confermata dall’analisi dei suoi comportamenti e del suo complesso intersecarsi con le scelte degli altri attori istituzionali di livello continentale. Al contrario, l’Eurotower avrebbe approfittato di quella drammatica congiuntura per allargare l’area delle proprie prerogative istituzionali e le avrebbe sistematicamente utilizzate per assecondare il progetto impopolare dell’Europa “austeritaria”, contribuendo in maniera decisiva ad orientare gli Stati membri verso l’adozione di strategie di policy ad impatto assai rilevante sugli equilibri distributivi tra categorie sociali e tra aree a differente struttura produttiva.

Uncertainties estimation is essential for a sound assessment and a clear definition of safety margins, which in turn are crucial for licensing approval of new nuclear reactors by safety authorities. Moreover, uncertainties are also matter for target accuracy requirements (TARs), whose achievement could disclose new or enhanced opportunities. The concept of target accuracy requirements has been over the years one of the returning focuses of Massimo Salvatores, who just recently relaunched an update exercise within the OECD/NEA Working Party on International Nuclear Data Evaluation Co-operation (WPEC) aiming at providing new estimates having as reference the advanced systems meant for tomorrow. This work presents an evaluation of the current accuracies on the main core integral parameters of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED), as a starting point to discuss which would be the target values that might introduce beneficial improvements in the design. Despite the use of one of the most recent nuclear data libraries (ENDF/B-VIII.0), and the broad margins set in the design of ALFRED according to its mission as demonstrator, room for improvement is found on the multiplication factor. Then, moving from the target accuracies on the integral parameters, an inverse uncertainty problem is solved to derive the corresponding target accuracies on nuclear data, meeting which would guarantee the achievement for the former ones. The inverse problem is solved introducing three different sets of cost parameters, reflecting possible challenges related to the execution of the differential experiments requested to achieve the aimed reductions of the accuracies. By this, the resulting target accuracies on nuclear data here presented are deemed useful to obtain information for the high-priority lists driving the selection of isotopes and reactions for future refinement experiments.

Depth estimation is crucial in several computer vision applications, and a recent trend aims at inferring such a cue from a single camera through computationally demanding CNNs — precluding their practical deployment in several application contexts characterized by low-power constraints. Purposely, we develop a tiny network tailored to microcontrollers, processing low-resolution images to obtain a coarse depth map of the observed scene. Our solution enables depth perception with minimal power requirements (a few hundreds of mW), accurately enough to pave the way to several high-level applications at-the-edge.

This work deals with the implementation of energy-efficient monocular depth estimation using a low-cost CPU for low-power embedded systems. It first describes the PyD-Net depth estimation network, which consists of a lightweight CNN able to approach state-of-the-art accuracy with ultra-low resource usage. Then it proposes an accuracy-driven complexity reduction strategy based on a hardware-friendly fixed-point quantization. Finally, it introduces the low-level optimization enabling effective use of integer neural kernels. The objective is threefold: (i) prove the efficiency of the new quantization flow on a depth estimation network, that is, the capability to retaining the accuracy reached by floating-point arithmetic using 16- and 8-bit integers, (ii) demonstrate the portability of the quantized model into a general-purpose 32-bit RISC architecture of the ARM Cortex family, (iii) quantify the accuracy-energy tradeoff of unsupervised monocular estimation to establish its use in the embedded domain. The experiments have been run on a Raspberry PI board powered by a Broadcom BCM2837 chipset. A parametric analysis conducted over the KITTI date-set shows marginal accuracy loss with 16-bit (8-bit) integers and energy savings up to 6.55× (9.23×) w.r.t. floating-point. Compared to high-end CPU and GPU the proposed solution improves scalability.

The concept of magnetic guidance has opened a wide range of perspectives in the field of tissue regeneration. Accordingly, the aim of the current research is to design magnetic responsive scaffolds for enhanced bone tissue regeneration. Specifically, magnetic nanocomposite scaffolds are additively manufactured using 3D fibre deposition technique. The mechanical and magnetic properties of the fabricated scaffolds are first assessed. The role of magnetic features on the biological performances is properly analyzed.

The EURATOM FP7 project FREYA was launched in 2011 to support the design and licensing of lead-cooled reactors, by choosing as reference the MYRRHA and ALFRED fast spectrum systems. During the five-year project, a number of critical experiments were conducted in the VENUS-F zero-power reactor with the main aim to validate the neutronic codes adopted for the core design. Five critical core configurations were assembled in VENUS-F: the start-up core, the mock-up dedicated to ALFRED and three layouts simulating the MYRRHA reactor conditions. The ERANOS code system, coupled with the JEFF-3.1 nuclear data library, was one of the tools adopted for the design and characterisation of the experiments. In this paper, the results obtained with the ERANOS deterministic code are compared with the experimental measurements of integral and local parameters, such as: the core reactivity and kinetic parameters, the lead void reactivity worth, the axial and radial distributions of fission rates for the nuclides of major interest, the spectral indexes of important actinides ( e.g. , U 238 , Pu 239 , Np 237 , Am 241 ) respect to U 235 . The comparison between measurements and simulations shows a general good agreement, with some discrepancies for few local parameters that are here discussed.

In the coming future, the electric energy production from nuclear power plants will be provided by both thermal reactors and fast reactors. In order to have a sustainable energy production through fission reactors, fast reactors should provide an increasing contribution to the total electricity production from nuclear power plants. Fast reactors have to achieve economic and technical targets of Generation IV. Among these reactors, Sodium cooled Fast Reactors (SFRs) and Lead cooled Fast Reactors (LFRs) have the greatest possibility to be developed as industrial power plants within few decades. Both SFRs and LFRs require a great R&D effort to overcome some open issues which affect the present designs (e.g. sodium-water reaction for the SFRs, erosion/corrosion for LFRs, etc.). The present paper is mainly focused on LFR fuel assembly (FA) design: issues linked with the high coolant density of lead or lead–bismuth eutectic cooled reactors have been investigated and an innovative solution for the core mechanical design is here proposed and analyzed. The solution, which foresees cylindrical fuel assemblies and exploits the buoyancy force due to the lead high density, allows to simplify the FAs locking system, to reduce their length and could lead to a more uniform neutron flux distribution.

After Fukushima events, the Italian nuclear program has been redefined leaving space only to activities related to Generation IV nuclear systems. Accordingly with this renewed national scenario, TAPIRO fast reactor facility is gaining a relatively major strategic role. A program is in fact being proposed to host in TAPIRO benchmark experimental activities related to the development of Lead fast reactor and Accelerator Driven Systems. A first step of this program would consist on the validation of neutronic codes, cross section data and reactor models to be adopted for its analysis. Along this line in this work the results of a simulation study has been made relevant to the measurements performed in the SCK-CEN/ENEA experimental campaign carried out in the 1980-1986 period. The calculations have been made using the Monte Carlo MCNPX 2.7.0 Code. In this article the main results are presented and discussed, with particular emphasis on the uncertainties, relevant both to nuclear data and the model layout. The results of this simulation study indicate in particular that TAPIRO's MCNPX model is adequate for the optimization of set-ups of perspective neutron irradiation experiments, this allowing cuts in costs and development time. © 2014 Elsevier B.V.