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Objective: To evaluate the family history of epilepsy in first degree relatives of probands with epilepsy. Methods: A sample of 10787 patients with epilepsy with complete information about first degree relatives (parents, siblings and offspring) was selected from the database of the Episcreen Project, the largest Italian observational study on epilepsy. Family history was assessed by: (1) prevalence estimates of epilepsy among proband's relatives, (2) modified cumulative risks (MCR), adjusted using proband's age as censoring time in life tables, (3) standardised morbidity ratios (SMR), using a sub-group of symptomatic epilepsies as control group. Results: Patients (9.1%) had a family history of epilepsy. The overall prevalence of epilepsy among first degree relatives was 2.6%. Idiopathic generalised epilepsies had the highest prevalence (5.3%). Cryptogenetic epilepsies had a lower prevalence (2.1%) than idiopathic epilepsies, but higher then symptomatic epilepsies (1.5%), both in generalised and focal forms (3.8% vs. 2.0% and 1.8% vs. 1.3%). A similar tendency was detected using MCR and SMR, with the higher values of risks/ratios for idiopathic and generalised epilepsies. Probands with idiopathic generalised epilepsies were highly concordant with respect to their relatives' type of epilepsy. Considering other strata factors, risks were higher in proband's epilepsies with an onset less then 14 years of age, while sex played no definite role in differentiating the family history. Conclusions: The Episcreen model permits a variety of stratification factors to measure family risk, including age at onset, epilepsy localisation and aetiology with a large sample of more than 10000 probands and 1065/40544 relatives affected and classified.

The design process of a device for energy harvesting from sea waves is a complex task, which involves many different stages ranging from the initial mathematical models to an extensive field testing. Scale models are a crucial tool to asses the real world device performance and to validate the mathematical models used in the design process. This paper describes the first laboratory campaign of the scale model of an Inertial Sea Wave Energy Converter (ISWEC). The experiments were carried out in the wave tank of INSEAN (The Italian ship model basin, Rome) between February and April 2012. ISWEC uses a gyroscope to create an internal inertial reaction able to harvest wave power without exposing mechanical parts to the harsh oceanic environment. As for other WECs, the theoretically optimal control of ISWEC should be able to adjust the dynamic parameters of the PTO, such as the spring constant and energy absorbing damping, to maximize the energy absorption. The aim of this manuscript is to explore the effect of PTO control parameters on energy production for a given incoming wave

A 3D Domain-Decomposition (DD) strategy has been developed to deal with violent wave-ship interactions involving water-on-deck and slamming occurrence. It couples a linear potential flow seakeeping solver with a Navier–Stokes method. The latter is applied in an inner domain where slamming, water-on-deck, and free surface fragmentation may occur, involving important flow nonlinearities. The field solver combines an approximated projection method with a level set technique for the free surface evolution. A hybrid strategy, combining the Eulerian level set concept to Lagrangian markers, is used to enforce more accurately the body boundary condition in case of high local curvatures. Main features of the weak and the strong coupling algorithms are described with special focus on the boundary conditions for the inner solver. Two ways of estimating the nonlinear loads by the Navier–Stokes method are investigated, on the basis of an extrapolation technique and an interpolation marching cubes algorithm, respectively. The DD is applied for the case of a freely floating patrol ship in head sea regular waves and compared against water-on-deck experiments in terms of flow evolution, body motions, and pressure on the hull. Improvement of the solver efficiency and accuracy is suggested. This is the pre-peer reviewed version of the following article: [3D domain decomposition for violent wave-ship interactions], which has been published in final form at [http://onlinelibrary.wiley.com/doi/10.1002/nme.4523/abstract]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

The gas-cavity problem with initially high pressure, evolving in a surrounding liquid, and interacting with a near body, is a very interesting research topic because it involves several physical phenomena and is of practical interest in different contexts. For instance, underwater explosions represent an important issue for ships and offshore structures. Therefore it is necessary to predict structural effects and try to improve vessel design. To this purpose, physical tests were performed along the years and theories were developed (Cole 1948). Another important application is in medical field. Implosion of micro-bubbles with ultrasound in biological flows is used within a noninvasive technique to remove calculi in human bodies (Lingeman et al. 2009). Here we first focus on the first application. When an underwater explosion occurs, a chemical reaction and a detonation process cause the formation of a hot gas with high pressure and the release of a shock wave traveling in the surrounding fluid. Then a superheated, spherical, bubble is formed which will first expand while the high pressure reduces in time and propagates in the surrounding liquid. Eventually the bubble starts to oscillate and affect the local pressure. In the first stage (shock wave) both the gas and the surrounding liquid behave as compressible, in the later stages (gas bubble) the acoustic wave will disappear and the water can be considered incompressible. The interaction of this two-phase fluid with a body will then depend on the vicinity of the body from the explosion zone and by the presence or not of other boundaries, e.g. the sea floor, the free surface.

Greco et al. (2011) tried to identify the proper numerical choices for the development of a three-dimensional DomainDecomposition (DD) strategy. It aims to study the violent interaction of FPSO ships with head-sea regular waves. The present work represents a contribution in this direction. The under development DD solver combines a Boundary Element Method (BEM) for the global linear seakeeping analysis in frequency domain with a Navier-Stokes (NS) method for the flow investigation in an inner sea region containing the forward portion of the vessel. In this region, water shipping and slamming events can be caused by the liquid-structure interactions, while it is assumed that the rest of the fluid domain can be suitably described by the linear potential-flow solver. Within the NS solver, a Projection method is adopted with a finite-difference scheme on an Eulerian grid and a Predictor-Corrector scheme for the time evolution. The solver is accurate to the second order. The evolution of the free surface is captured by means of a Level-Set (LS) technique updating in time the normal distance (with-sign) from the water-air interface. Moreover the influence of the air on the water is neglected and the velocity field is smoothly extended from the liquid to the gas domain. The non-slip bodyboundary condition is enforced through a hybrid Eulerian-Lagrangian approach combining the body LS function ?body (positive in the fluid) with point markers moving with the body and initially defined on a uniform grid four times finer than the minimum mesh size in the computational grid and within a band across the body surface six times larger than the maximum mesh size of the computational grid. The body points evolve in time carrying with them their distance from the body surface and this allows a more accurate estimate of ?body on the Eulerian grid by interpolation from the markers. The coupling between the outer and inner solvers is implemented as a weak and a strong strategy. In the former case, the information travels from the outer to the inner solver but not vice versa; in the latter, the information travels back and fourth. The NS solver needs initial and boundary conditions in terms of velocity, pressure and free surface elevation in the fluid and the body-boundary condition along the solid surface. The seakeeping solver feels the nonlinearities and possible viscous effects predicted in the inner domain through local and global loads acting on the ship portion inside this region. The rest of the ship hull is assumed to be subjected to the loads provided by the potential-flow outer solver. For a freely-floating vessel, the inner-domain global loads are introduced in the body-motion equations, so that the ship motion can be affected by the inner-flow features that can alter the flow pattern in the inner domain in return.

The Lattice Boltzmann Method (LBM) has been introduced about 20 years ago (see [1] and [2]), but only the recent development of a multiple-relaxation-time (MRT) collision model [3] has allowed its application to a wide range of Reynolds numbers. The comparison of its results with those obtained with a DNS incompressible-flow spectral element solver has also shown that it can correctly capture the details of the fluid turbulence [4], preserving its basic features of simplicity, flexibility and intrinsic parallelism. For these last features and for its enhanced suitability to deal with viscous flows, the LBM starts to be appealing to deal with high vorticity generated in water and its interaction with the both the solid and deformable boundaries as the air-water interface. For moving vehicles, e.g. submarines and airplanes, vorticity generation and its interaction with the downstream body part can cause boundary layer separation and transition to turbulence with a dramatic effect on the unsteady forces [5]. Here, we present the application of the MRT Lattice Boltzman model to a variety of fluid-body interaction dealing with vorticity generation and dissipation. The vorticity is either generated in 2D or 3D lid driven cavity. The computed flow features are widely compared with data available in literature. In particular, the velocity, vorticity and pressure evolution are analyzed versus the same quantities obtained with Navier-Stokes solutions or in the experiments. The results show convergence and accuracy of the LBM solver. Finally, the 3D problem of a vortex ring impacting on a flat wall is analyzed. The effects of the interaction with the solid boundary are highlighted: dissipation at low Reynolds (Re) numbers, instabilities at high Re.

This research activity represents an additional step toward a three-dimensional Domain-Decomposition strategy for violent wave-ship interaction involving water-on-deck and slamming phenomena. The focus is on FPSO ships and on head-sea waves and vessel without forward speed. The compound solver under development aims to couple a global 3D linear seakeeping solver with an inner 3D single-phase (water) Navier-Stokes (NS) method in a region containing the forward portion of the vessel. The NS solver is characterized by a Projection method with a finite-difference scheme on an Eulerian grid. The Level-Set (LS) technique is applied to step in time the free surface and combined with point markers to enforce adequately the body-boundary condition within a hybrid Eulerian-Lagrangian approach. This requires a much finer discretization than the computational grid around the body to preserve its geometrical details in time. As time goes on, the markers move in a Lagrangian fashion and then the LS function is estimated on the Eulerian grid by interpolation from the markers locations. Previous efforts have been documented for instance in Greco et al. (2009)) and Colicchio et al. (2010). Here some of the challenges and the possible solutions for the development of the inner 3D NS solver are discussed. The stress is on the boundary conditions.

The present analysis is a part of a research activity aimed to develop a numerical method reliable and efficient for seakeeping problems with water-on-deck occurrence. Highlighting the need for efficient solutions, the Domain-Decomposition (DD) algorithm was chosen. A two-dimensional DD strategy has already been developed and assessed by comparison against experimental data and other numerical results for fluid dynamic problems similar to the one of interest. Its details can be found for instance in Colicchio et al. (2006) and Greco et al. (2007) and have been documented also at previous workshops. A preliminary 3D analysis was obtained combining a weakly-nonlinear potential flow solver for the external seakeeping problem with an in-deck shallow-water approximation to handle the water-on-deck events (see i.e. Greco et al. 2009). This has the advantage of being very efficient but has limitation in terms of validity because the nonlinearities involved in the water-ship interactions are accounted for only partially. Just to mention, the water run-up is not properly described when high-speed jets are formed and the plunging-wave phase, which usually characterizes the initial stages of the water shipping, is not captured.

The water-on-deck is a transient nonlinear phenomenon induced by wave-vessel interactions, especially when severe incident waves and large vehicle motions happen. Green water is characterized by compact masses of liquid exceeding locally the freeboard, they enter the vessel and may flow/slosh/impact on the deck. The vessel type, its operational conditions and the incident-wave features are the major parameters of the problem, affecting the occurrence, severity and behavior of the shipped water. Green-water loads may be characterized by high localized peaks, as well as by a more persisting and global behavior. They represent a danger for safety, operations and comfort.

Present investigation concerns the further development of the numerical potential-flow method described in Greco et al. (2008). This couples (A) a 3D weakly nonlinear solver based on the weak-scatterer hypothesis (Pawlowski 1991) with (B) a 2D shallow-water solver on the deck plane, which handle,respectively, the ship seakeeping and the water shipping. The boundary conditions for the shallow-water problem have been improved when a bulwark is present, both in terms of the deck-plane velocity (u, v) and of the water level h: the partial reduction of the water flow through the local deck contour and the partial reflection of the liquid by the obstacle are accounted for. The former is introduced as a correction of the shallow-water velocity solution, the latter is enforced as a liquid layer to be added to the deck-contour water level given as boundary condition by the external field. The latter, i.e. the h boundary condition from the seakeeping problem is different than zero only during a water-on-deck phase. A simplified criterion for the slamming occurrence has been implemented, based on the impact angle and the pressure level associated with the phenomenon. The slamming and water-entry local loads were handled by means of a Wagner-theory approach (Wagner 1932). The solution method has been extended to handle the forward motion of the vessel, under the assumptions of small ship speed Uship and following the work by Salvesen et al. (1970). It means that the forward-motion effects are introduced as an explicit correction of: (a) the zero-speed frequency-dependent hydrodynamic coefficients, (b) the Froude-Krylov load contribution and (c) the wave field around the vessel. This approximation has the advantage of being computationally cheap, but its applicability is limited and must be assessed. Finally, the solver description of the incoming waves has been extended to handle irregular waves as a superposition of linear regular waves. Regular-sea conditions are described instead as second-order Stokes'waves.

The dependence on the Reynolds number of shallow depth sloshing flows inside rectangular tanks subjected to forced harmonic motion is studied in this paper with weakly compressible SPH. We are interested in assessing the in fluenceof viscous effects on the dynamics of shallow depth sloshing flows by using an SPH solver and by comparing with a Navier-Stokes level-set solver results. The goal of trying to model these viscous flows is compromised by the resolution requested due to their Reynolds number, if boundary layer effects are to be modeled. The convenience and feasibility of the implementation of free-slip and no-slip boundary conditions is also discussed

Several water flow problems of practical interest are characterized by fluid regions where the flow evolution is efficiently de- scribed by the potential theory, and other regions where this model is not valid. For instance, confined fluid areas can experience large air-water interface deformations followed by wave breaking and fragmentation phenomena. Limited water portions can be characterized by substantial vorticity generation due to water-water or water-structure interaction. In these cases the surrounding fluid domains can be slightly affected by such events. The ship hydrodynamic field is full of similar circumstances. The water-on-deck problem represents an example. In this case, compact masses of water enter the ship deck and the subsequent motion can result in important loads for the deck superstructures. On a long time scale, water breaking, air entrainement and vorticity generation are expected to occur. The later water-off-deck phase will cause the re-entering of water in the sea surrounding the vessel. As a result, near the vessel the free surface cannot be modeled as a smooth surface. Both the water shipping event and the final water-entry phase can involve substantial induced water loads on the vessel and large movements of the ship. Therefore related phenomena are of great interest for ship hydrodynamics, both from the operability and safety points of view. Due to the large free-surface deformations involved, a nonlinear analysis is needed. Before breaking and/or vortex shedding events, potential flow theory can capture accurately and with computational efficiency the involved flow evolution and predict connected loads and motions. After that, in the water regions where such phenomena occur and develop, this model has to be substituted by more general methods suitable to track the free surface deformations after the breaking, to handle the flow vorticity introduced in the fluid domain and to model the entrapped air. The present research activity is aimed to develop a numerical method able to simulate such ship flows and to adapt itself to the specific analyzed problem for an efficient and suitable solution. This has been done by considering a domain-decomposition strategy (see i.e. Quarteroni and Valli 1999, Campana and Iafrati 2001) .

Theoretical and numerical analysis of the internal waves phenomenon. The feasibility of the setting up of an experimental apparatus for the analysis of the problem is also carried on

Background: Vagus nerve stimulation (VNS) is a palliative treatment for medical intractable epileptic syndromes not eligible for resective surgery. Health technology assessment (HTA) represents a modern approach to the analysis of technologies used for healthcare. The purpose of this study is to assess the clinical, organizational, financial, and economic impact of VNS therapy in drug-resistant epilepsies and to establish the congruity between costs incurred and health service reimbursement. Methods: The present study used an HTA approach. It is based on an extensive detailed bibliographic search on databases (Medline, Pubmed, Embase and Cochrane, sites of scientific societies and institutional sites). The HTA study includes the following issues: (a) social impact and costs of the disease; (b) VNS eligibility and clinical results; (c) quality of life (QoL) after VNS therapy; (d) economic impact and productivity regained after VNS; and (e) costs of VNS. Results: Literature data indicate VNS as an effective treatment with a potential positive impact on social aspects and on quality of life. The diagnosis-related group (DRG) financing, both on national and regional levels, does not cover the cost of the medical device. There was an evident insufficient coverage of the DRG compared to the full cost of implanting the device. Conclusions: VNS is a palliative treatment for reducing seizure frequency and intensity. Despite its economic cost, VNS should improve patients’ quality of life and reduce care needs.

To evaluate whether vagus nerve stimulation (VNS) as adjunct to best medical practice (VNS + BMP) is superior to BMP alone in improving long-term health-related quality of life (HRQoL).PuLsE (Open Prospective Randomized Long-term Effectiveness) was a prospective, randomized, parallel-group, open-label, and long-term effectiveness study (conducted at 28 sites in Europe and Canada). Adults with pharmacoresistant focal seizures (n = 112) received VNS + BMP or BMP (1:1 ratio). Medications and VNS parameters could be adjusted as clinically indicated for optimal seizure control while minimizing adverse effects. Primary endpoint was mean change from baseline HRQoL (using Quality of Life in Epilepsy Inventory-89 total score; QOLIE-89). Secondary endpoints included changes in seizure frequency, responder rate (≥50% decrease in seizure frequency), Centre for Epidemiologic Studies Depression scale (CES-D), Neurological Disorders Depression Inventory-Epilepsy scale (NDDI-E), Clinical Global Impression-Improvement scale (CGI-I), Adverse Event Profile (AEP), and antiepileptic drug (AED) load. The study was prematurely terminated due to recruitment difficulties prior to completing the planned enrollment of n = 362. Results for n = 96 who had baseline and at least one follow-up QOLIE-89 assessment (from months 3-12) were included in this analysis. Mixed model repeated measures (MMRM) analysis of variance was performed on change from baseline for the primary and secondary endpoints.Significant between-group differences in favor of VNS + BMP were observed regarding improvement in HRQoL, seizure frequency, and CGI-I score (respective p-values0.05, 0.03, and 0.01). More patients in the VNS + BMP group (43%) reported adverse events (AEs) versus BMP group (21%) (p = 0.01), a difference reflecting primarily mostly transient AEs related to VNS implantation or stimulation. No significant difference between treatment groups was observed for changes in CES-D, NDDI-E, AEP, and AED load.VNS therapy as a treatment adjunct to BMP in patients with pharmacoresistant focal seizures was associated with a significant improvement in HRQoL compared with BMP alone. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.