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During the DEMO Pre-Conceptual Design Phase, a strong effort has been made within the EUROFusion Consortium to define a methodology for the implementation of consistent electromagnetic (EM) analyses on the Breeding Blanket (BB) system, being EM loads during normal and off-normal operations an important input for its structural assessment. Due to the complexity of the considered system, EM loads are evaluated using EM codes (e.g. ANSYS Emag, MAXWELL, CARIDDI) that rely on various numerical modeling approaches. However, independent from the used code, the evaluation of the EM loads in tokamak reactors is not straightforward and must to cope with different problems: the implementation of all sources of magnetic field (in particular the plasma during its evolution); the identification of conductive structures that contribute to the behavior of the eddy currents inside the region of interest; a reasonable simplification of the implemented model to reduce the computation time. This work aims to give an overview of the EM methodology applied to the BB structure analyzing the impact of the used assumptions and simplifications. Particular attention is given to the EM loads generated during plasma instabilities that give rise to severe electromagnetic transients characterized by a fast variation of toroidal and poloidal flux. The contribution of ferromagnetic materials, as well as induced (eddy and halo) currents and electrical contacts with VV, are reviewed identifying, when possible, the qualitative behavior and main parameters that determine the magnitude of the generated EM loads.

The present work focuses on the design assessment of the DEMO Upper Port. The size of the upper port is defined by the available space in between the toroidal field coils and the required space to integrate a thermal shield between the vacuum vessel (VV) port and the coils. Since the large breeding blanket (BB) segments will require periodic replacement via the upper vertical ports the space inside the upper port needs to be maximized. For this reason the optimization and verification of the upper port design is a critical aspect in the development of DEMO project. The work here presented investigates the possibility to have an upper port with single walled sidewalls to increase the space available inside the port for the integration of pipe work and to allow the handling of the BB segments. The work carried out evaluates the feasibility of the design solution from the structural and thermal point of view verifying the upper port structure against nuclear heating, in-vessel pressure, and electromagnetic loads due to a toroidal field coil fast discharge and plasma disruptions according to nuclear codes. © 2018 Elsevier B.V.

The research carried out over the past years within the Breeding Blanket (BB) project has demonstrated the importance of considering electromagnetic (EM) loads for the structural assessment of BB segments and the design of some interface components (e.g. attachment system with VV). These loads act on the structure during normal and off-normal operation and their distribution and magnitude strongly depend on the tokamak magnetic configuration, BB segment design and its electrical connections with the other conductive structures, as well as on the considered plasma scenario. The following work focuses on the Helium Cooled Pebble Bed (HCPB) BB. It reports an update of the electromagnetic loads for the DEMO2017 baseline during the plasma flat top and a VDE-up with a current quench time of 74 ms. Ferromagnetic and Lorentz loads (comprehensive of halo current contribution) have been calculated using an ANSYS FEM model. The obtained results are compared with the previous one (DEMO2015 baseline), showing the impact due to the change in the HCPB design and electrical contacts with the VV.

This work presents the development of a DEMO EM model based on the WCLL design able to evaluate EM loads during normal and off-normal operations. The model has the capability to use periodic boundary conditions (in order to analyze EM transients in presence of both toroidal and poloidal field) and elements supporting non-linear magnetic properties. Eddy currents and related EM loads are calculated considering a VDE-up provided by CarMa0NL code with a 74 ms current quench time. Both the poloidal and toroidal field variations due to the plasma movement and to the current quench are implemented. The obtained results represent an important input for the structural assessment of the BB segments as well as for the definition of the attachment system with the VV.

Considerable effort is made within the EUROfusion consortium to analyse the electromagnetic (EM) loads that act on the in-vessel components of DEMO during normal and off-normal operations. These loads are important, often design driving, inputs for the structural assessment of such components. With regard to the Breeding Blanket (BB) project, a global DEMO EM model, suitable to account for different blankets designs, has been developed in previous years with the capability to analyse EM transients in presence of both toroidal and poloidal magnetic field and considering materials with non-linear magnetic properties. Using the FEM model based on the Water-Cooled Lithium Lead (WCLL) design, a VDE-up with a 74 ms current quench time was analysed. With respect to previous analyses, only focused on eddy currents (and thus, respective Lorentz forces), the present work completes the EM analysis of the BB segments evaluating the interaction of the BB magnetised material with the magnetic field (ferromagnetic forces) and the contribution of halo currents. Moreover, in order to follow the ongoing development of BB concepts, a comparison between the Single Module Segmentation (SMS) and Multi Module Segmentation (MMS) is also made, giving thus a complete view of the EM loads behaviour during the considered off-normal event.

Fusion advanced study torus (FAST) has been designed with the aim to tackle the power exhaust problem with ITER and DEMO relevant bulk plasma. Considerable analysis effort has been spent in EM (electromagnetic) designing of FAST divertor components capable of withstanding the electromagnetic loads expected from the foreseen FAST operative conditions. Plasma disruption EM loads are one of the most critical load conditions for the divertor. Consequently a first dimensioning of the divertor for EM loads is mandatory. The foreseen FAST divertor structure is compact and the configuration is aimed to give to the structure the required mechanical and thermal capability as well as being remote handling compatible. The conceptual EM design of the divertor has been designed for FAST operative conditions and for DEMO relevant "Snow Flake" (SF) magnetic topology. Recently a "Snow Flake" (SF) magnetic topology has been suggested for the divertor region, capable to spread the plasma power flow on a much wider areas, with the possibility of reducing by a factor 4 the power flowing to the divertor tiles [1]. The conceptual design of the divertor has been obtained during activities based on the estimation of EM loads due to a typical Plasma Fast Down disruption event in FAST for the normal configuration and for SF magnetic topology. © 2013 Elsevier B.V.

In ITER two heating (HNBI) and one diagnostic neutral beam injectors (DNBI) are foreseen. Inside these components there are very stringent limits on the magnetic field (the flux density must be below some G along the ion path and below 20 G in the neutralizing regions). To achieve these performances in an environment with high stray field due to the plasma and the poloidal field coils (PFC), both passive and active shielding systems have been foreseen. The present design of the magnetic field reduction systems (MFRS) is made of seven active coils and of a box surrounding the NBI region, consisting of ferromagnetic plates. The electromagnetic analyses of the effectiveness of these shields have been performed by a 3D FEM model using ANSYS code for the HNBI. The ANSYS models of the ferromagnetic box and of the active coils are fully parametric, thus any size change of the ferromagnetic box and coils (linear dimension or thickness) preserving the overall box shape could be easily reproduced by simply changing some parameter in the model.

In ITER machine, the In-Wall Shielding (IWS) blocks are arranged between vacuum vessel double walls in order to screen the neutrons. Some of these blocks are made of ferromagnetic material plates (ferromagnetic insert) in order to reduce toroidal magnetic field ripple and then they undergo Maxwell forces during ITER operations. The In-Wall Shielding blocks have to be dimensioned not only for neutron shielding but also for eddy current and magnetization forces. In the frame of the ITER Organization (IO) design review activity, the feasibility of In-Wall Shielding blocks with ferromagnetic inserts requires a detailed analysis using Finite Element (FE) detailed approach. The Maxwell forces acting on the IWS blocks were evaluated using PVW (Principle of Virtual Works) and MST (Maxwell Stress Tensor). This paper outlines the engineering aspects from the EM point of view of the ITER IWS blocks and focuses on the EM feasibility of the present design.

The distribution of forces, acting on components of the electromagnetic (EM) system considered herein has been analyzed with the use of simplified models and equivalent dynamic simulators for a variety of plasma event scenarios. The work was aimed at the formulation of the problem of the global force balance and the approach to its resolution, identification of the main factors of the force interaction between components, development of the numerical models for qualitative and quantitative assessment of the problem and relevant parameters and the computations and assessment of the results. The use of equivalent simulators with elimination of redundant details and degrees of freedom (DOFs) principally reduces computational complexity of the problem. The selection (identification) of the equivalent system on the basis of the evaluation of the significance of impacts on the parameter of interest provides the effective and natural filtering of secondary or irrelevant information. The finding of equivalent minimum dynamic systems (EMDS) opens, at a certain rate of computations, a way to develop real-time simulators. The paper describes simplified models, the principles of definition (synthesis) and use of EMDS, the structure of the database (magnitude and time evolution of distributed and integral basic parameters) required for the evaluation of the EM loads and examples of the data.

During asymmetric vertical displacement events (AVDEs) associated with the kink mode of the plasma two asymmetry phenomena were observed in existing tokamaks, in particular in JET [1]. The related halo currents flowing in the passive structure were identified as the cause of asymmetric EM loads on tokamak components. The first phenomenon is a toroidal peak of the poloidal halo current that flows in the passive structure. The second phenomenon is that the toroidal plasma current is not uniform toroidally, so a toroidally non-uniform current flows in the vessel [2]. The specification of the expected characteristics of both phenomena as well as of the consequent asymmetric loads in ITER are summarized here. The related loads are specified for likely, unlikely and extremely unlikely AVDEs.

ITER diagnostic components are installed within the vacuum vessel, and in vacuum vessel ports at the upper, equatorial and divertor levels. The installation and integration issues are different in each of these 4 locations. In the divertor, diagnostic components are concentrated in the cassettes which are remote handleable through divertor ports. Of the 54 divertor cassettes, 16 are dedicated to various diagnostics. These include both optical diagnostics where light is relayed through the divertor ports, and electrical sensors. Diagnostic equipment in the divertor cassette itself is integrated in a protected housing, called a “mirror box” cooled with the cooling water of the divertor cassette. In the divertor ports, diagnostic equipment is installed in a diagnostic support structure called the diagnostic rack. Permanent cabling for instrumented and diagnostic cassettes is routed along the port.

A new facility for fusion, the Fusion Advanced Studies Torus ( FAST ), has been proposed to prepare ITER scenarios and to investigate non linear dynamics of energetic particles, relevant for the understanding of burning plasmas behavior, using fast ions accelerated by heating and current drive systems. This new facility is considered an important tool also for the successful development of the demonstration/prototype reactor (DEMO), because the DEMO scenarios can take valuable advantage by a preparatory activity on devices smaller than ITER with sufficient flexibility and capable plasma conditions, before to testing them on ITER itself. In the regimes proposed for FAST the magnetic Toroidal Field (TF) ripple could lead to significant losses of high-energy particles, as also demonstrated in JET and JT60U experiments 1&2 , so a careful analysis is necessary to achieve a low value of the TF ripple as far as compatible with the general load assembly design issues. Two different approaches to reduce TF ripple had been considered: Ferromagnetic Insets and Active Coils. For both solutions, different geometric parameters were investigated and the relative benefits and drawbacks evaluated. The analysis was carried out by 2D and 3D electromagnetic F.E.M codes, dealing with different design solutions, chosen between those compatible with the relevant geometric dimensions of the plasma (i.e. the vacuum vessel), the access to the plasma and the divertor needs (i.e. the vacuum vessel ports dimensions) and other design constrains. A magnet consisting of 18 coils, each made of 14 copper plates suitably worked out in order to realize 3 turns in radial direction has been proposed. To limit within acceptable value the TF magnet ripple, the ferromagnetic insets solution has been chosen for FAST. The ripple on the plasma separatrix (near the equatorial port), has been so reduced from 3% to 0.3%. Due to the good results obtained also with Active Coils a study for applying the Active Coils concept also in ITER design was made, confirming even in this case the possibility to reduce considerably the TF ripple.

The present work evaluates, using 3D finite element (FE) electromagnetic (EM) analyses, the poloidal field coil (PFC) stray field reduction inside and outside the main ITER building due to the presence of ferromagnetic content in the concrete and other iron components outside the vessel (mainly the huge iron boxes of the NBI – neutral beam injector – and the iron doors at the end of the port corridors). To perform these analyses a 360° 3D EM model of the ITER building has been developed, named electromagnetic model of the building complex (EMMOBC), which includes the poloidal field coils, the plasma, a coarse model of the two heating & current drive (H&CD) NBIs, the coils of the NBI active magnetic field reduction system, and all the main building components that could include ferromagnetic materials. The plasma scenarios at the start of flat-top (SOF) and at the end of burning (EOB) have been considered. The effect on the stray field on the NBI due to the presence of the active (AMFRS) and passive (PMFRS) magnetic field reduction system of the near NBI and of the others iron component in the building has been evaluated, using EMMOBC that include the coarse model of the two NBIs. The coil currents of the AMFRS in the H&CD NBI have been optimized for the stray field coming from the SOF and EOB plasma scenarios at plasma current of 15 MA. The stray field at SOF and EOB, including the effects of the ferromagnetic iron content (outside the vessel), has been evaluated inside and outside the main ITER building using the EMMOBC. Finally the field perturbation produced on the plasma q = 2 surface has been evaluated.

Two different approaches to control the Toroidal Field Ripple (TFR) amplitude in ITER and FAST devices are presented in this paper. The approach currently adopted to reduce the TFR in ITER is based on the installation of ferromagnetic inserts between the vacuum vessel shells. The same approach has been analyzed in the design of the Fusion Advanced Studies Torus (FAST) proposal. Details of the system's layout are given. A new approach based on the insertion of active coils between the outer legs of the Toroidal Field Coils (TFCs) and the plasma, has been extensively investigated for these two machines. This active system would allow reducing the TFR to values even smaller than with the ferromagnetic inserts. The case of a localized disturb like that introduced by a Test Blanket Module (TBM) for ITER is presented where only well localized active coils can produce a significant ripple reduction.

An accurate evaluation of the toroidal field ripple in ITER has been carried out by finite element models including the presence of the 18 TF coils and a set of ferromagnetic inserts that aim to lower the field ripple well below 1%. As shown, a set of ad hoc distributed plates made of AISI 430 stainless steel (Bsat = μ0Msat ∼1.5 T) and located at the outboard plasma region side in between the vessel shells can reduce the peak ripple at the plasma boundary to ∼0.4% at full toroidal field (i.e., BTF ∼5.3 T at R = 6.2 m). Better compensation can be achieved by adopting higher magnetic saturation materials (e.g., EUROFER). The Test Blanket Modules pair modeled here and made of EUROFER (Bsat ∼1.8 T at 300 K) introduces a large perturbation to the field ripple up to ∼1.1% at full field.

Static and transient analyses have been carried out to evaluate Electro Magnetic loads on the European Helium Cooled Pebble Bed Test Blanket Module (HCPB-TBM) during a type II linear disruption (Lorentz forces) and (because of the presence of ferromagnetic structural material) during normal ITER operating scenario (Maxwell forces (MFs)). At last the influence of the toroidal field ripple on the MFs has been investigated.

A detailed evaluation of the EM loads in the ITER divertor during plasma disruptions is mandatory for the correct dimensioning of the divertor component. The EM loads during plasma disruptions are mainly produced by: (1) toroidal flux variation (TFV) during the thermal quench (TQ) and current quench (CQ); (2) halo currents (HC); and (3) poloidal flux variation (PFV) during TQ and CQ phase. The new ITER reference disruption and the last changes in the divertor design have been considered in the EM models created to calculate all the EM loads due to TFV, HC and PFV. All the analyses have been performed for the three different main design options of the divertor plasma facing units (PFU). The effects of PFV have been analyzed using an EM-zooming procedure that has allowed a good detail of the component model, while new numerical approaches have been developed for the evaluation of the effects due to TFV and HC maintaining the same detail for the divertor model. Separate models have been developed to evaluate the equivalent electrical resistivities of the various PFU options; this allows in the full 3D model a strong simplification of a geometry which would otherwise be very complex. The effect of an electrical surface bridging of the PFU castellation has also been taken into account.

The European fusion programme is ‘reactor oriented’ and it is aimed at the successive demonstration of the scientific, the technological and the economic feasibility of fusion power. The European Power Plant Conceptual Study (PPCS) has been a study of conceptual designs of five commercial fusion power plants and the main emphasis was on system integration. It focused on five power plant models which are illustrative of a wider spectrum of possibilities. They are all based on the tokamak concept and they have approximately the same net electrical power output, 1500 MWe. These span a range from relatively near-term, based on limited technology and plasma physics extrapolations, to an advanced conception. The PPCS allows one to clarify the concept of DEMO, the device that will bridge the gap between ITER and the first-of-a-kind fusion power plant. An assessment of the PPCS models with limited extrapolations highlighted a number of issues that must be addressed to establish the DEMO physics and technological basis.

Kabuki syndrome (KS) (Kabuki make-up syndrome, Niikawa-Kuroki syndrome) is a rare genetic disorder first diagnosed in 1981. Kabuki make-up syndrome (KMS) is a multiple malformation/intellectual disability syndrome that was first described in Japan but is now reported in many other ethnic groups. KMS is characterized by multiple congenital abnormalities: craniofacial, skeletal, and dermatoglyphic abnormalities; intellectual disability; and short stature. Other findings may include: congenital heart defects, genitourinary anomalies, cleft lip and/or palate, gastrointestinal anomalies including anal atresia, ptosis and strabismus, and widely spaced teeth and hypodontia. The KS is associated with mutations in the MLL2 gene in some cases were also observed deletions of KDM6A. This study describes three children with autism spectrum disorders (ASDs) and KS and rehabilitative intervention that must be implemented.

The fusion advanced study torus (FAST), with its compact design, high toroidal field and plasma current, faces many of the problems met by ITER, and at the same time anticipates much of the DEMO relevant physics and technology. The conceptual design of the first wall (FW) and the vacuum vessel (VV) has been defined on the basis of FAST operative conditions and of "Snow Flakes" (SF) magnetic topology, which is also relevant for DEMO. The EM loads are one of the most critical load components for the FW and the VV during plasma disruptions and a first dimensioning of these components for such loads is mandatory. During this first phase of R&D activities the conceptual design of the FW and VV have been assessed estimating, by means of FE simulations, the EM loads due to a typical vertical disruption event (VDE) in FAST. EM loads were then transferred on a FE mechanical model of the FAST structures and the mechanical response of the FW and VV design for the analyzed VDE event was assessed. The results indicate that design criteria are not fully satisfied by the current drawing of the VV and FW components. The most critical regions have been individuated and the effect of some geometrical and material changes has been checked in order to improve the structure. © 2015 Elsevier B.V. All rights reserved.

The possibility of using liquid lithium as plasma facing component for the divertor target plates will be investigated on FTU by employing an innovative solution that exploits the surface tension forces in capillary channels to compensate j × B forces induced in lithium. For this structure, a high stability and resistance is foreseen as well as an intrinsic capability to self-regenerate the plasma facing surface. FTU represents the first very good opportunity to test this configuration, called capillary porous system (CPS), in an ITER relevant experiment at high plasma density (up to 3.2 × 10 20 m −3 ), high current (up to 1.6 MA) and high magnetic field (up to 8 T). As first step of its application on FTU, foreseen for the second half of 2005, CPS system will be employed for a “litization” experiment aimed to reduce plasma contamination and recycling.

During a plasma disruption in Ignitor [B. Coppi, IGNITOR Project Group, Engineering Design Description, Ignitor Programme, RLE Report no. PTP 96/03, December 1996], the electromagnetic (EM) loads are so large to require a dynamic elastic–plastic structural analysis of the plasma chamber (PC). A 30° sector of PC has been modeled. Static, dynamic and low cycle fatigue analyses under eddy and halo currents have been performed. It is shown that a PC wall thickness optimization limits the displacements within the clearance with toroidal coil. The fatigue lifetime is longer than the number of disruption events at the maximum performance.

The main design features and guidelines for the construction of the 8-T cryogenically cooled Frascati Tokamak Upgrade (FTU) are presented. The main features include the very compact toroidal magnets based on the concept of the 'Bitter' type of coil with wedge-shaped turns, utilized for the first time for the Alcator A and C magnets, and the original configuration of the vacuum vessel (VV) structure, which is fully welded in order to achieve the required high strength and electric resistivity. The present toroidal limiter has been installed following several years of operation, and this installation has required the development of specific remote-handling tools. The toroidal limiter consists of 12 independent sectors made of stainless steel carriers and molybdenum alloy (TZM) tiles. The main fabrication processes developed for the toroidal and poloidal coils as well as for the VV are described. It is to be noted that the assembly procedure has required very accurate machining of all the structures requiring several trials and steps. The machine has shown no problem in operating routinely at its maximum design values (8 T, 1.6 MA)

A comprehensive design of the ITER divertor has been developed within the EU R&D for ITER. It consists of plasma facing components (PFCs) and cassettes body (CB). The PFCs are actively cooled thermal shields while the CB are massive supports for the PFCs providing also a neutronic shield. The present paper gives a detailed design of the PFCs and the CBs. It includes the cooling path, the manifolds, the attachments between the PFCs and the CBs and those between the CBs and the vacuum vessel (VV). The design has been carried out with a series of analyses. The neutronics analysis assures the shielding efficiency of the PFCs/CBs towards the rear components, and calculates the radiation loads in the key points. The electromagnetic (EM) analysis evaluates the loads due to eddy and halo currents. The thermo–hydraulic analysis verifies the effectiveness of the cooling circuit regarding the minimum margin critical heat flux (CHF) and the maximum acceptable pressure drop. The thermo-mechanical analysis verifies the integrity of the components under coolant pressure, neutron/plasma thermal loads and EM loads. The work, done with the collaboration of professionals from different organisations, shows that the proposed design of the components fulfils all the requirements of the ITER FEAT machine.

A new concept of radial passive and active press, to replace the previous axial design is presented in this paper. This solution reduces the stresses in the components concerned and at the same time it improves the assembly, operation and maintenance of the machine.

A new cassette concept based on a welded box structure made of stainless steel plates has been proposed for ITER FEAT. In this paper a summary of the analysis of the design is provided. Due to lack of space all the interesting multidiscipline items cannot be mentioned, but only the main results are presented. A complete report on the activity is in (Final report on Design of Welded Box Divertor Cassette ENEA Report FUS TN DI-NE-R-001, February 2001). The work, which has involved professionals coming from different institutes, shows that all the design requirements are fulfilled in normal operational conditions. The halo currents induce deformations close to the allowable limits. Therefore, some reinforcement of the cassette or some modifications of the attachment system to the Vacuum Vessel (VV) will be studied in the future design activities to reduce the displacement.

The ITER reference breeding blanket design is water-cooled and is characterised by the use of the neutronic multiplier and breeder materials in the form of pebbles. Besides the achievement, with margin, of the tritium breeding ratio (TBR) minimum requirement, it exhibits an internal layout allowing it to withstand properly electromagnetic loads during plasma disruption and vertical displacement events, and pressure loads in case of rupture of an internal cooling channel (i.e. in-box LOCA). During the first part of 1998, the design has been optimised improving the performance in terms of TBR, enlarging the design margins with respect to the dimensioning loads and investigating in detail the global behaviour of the system during normal and off-normal conditions.

We have previously shown an imbalance of the antioxidant system in some cultures of normal melanocytes from patients with melanoma. In order to evaluate if the alteration of the antioxidants could be the basis of an increased sensitivity to exposure to peroxidative agents, in cultured melanocytes from normal individuals (n = 11) and from patients with melanoma (n = 11), superoxide dismutase and catalase activities were evaluated by spectrophotometer, and the levels of vitamin E and of the polyunsaturated fatty acid of cell membranes were determined by gas chromatography mass spectrometry. In 5 out of the 11 cultures of melanocytes from melanoma patients, with respect to those from normal individuals, a significant decrease of catalase activity (Cat) associated with an increase of vitamin E (Vit E) concentration was found, whereas no significant modification of superoxide dismutase activity (SOD) was observed. A wide range of variability was detected in the percentage of the polyunsaturated fatty acids of the cell membranes and a correlation was found between the ratio SOD/Cat and the percentage of linoleic acid, indicating that the imbalance of the enzymatic antioxidants leads to a lipoperoxidative process. The electron microscopic examination of these cultures revealed many microvilli in the plasma membranes and nuclear infoldings and in the cytoplasm light vacuoles. Moreover some cells contained several dense bodies with a round shape and numerous spherical lamellae possibly representing immature melanosomes. Treatment with cumene hydroperoxide between 0.66 and 20 microM did not produce a significant modification of cell viability in melanocytes from normal individuals. On the contrary in melanocytes from melanoma patients correlated with the ratio Vit E/Cat, considered as a parameter of the antioxidant imbalance, a stimulatory effect was observed at 0.66 microM CUH and a cytotoxic effect at 20 microM. In conclusion our results suggest that a constitutional alteration of the scavenger system could be present in normal melanocytes from melanoma patients and that this could be the basis for an increased sensitivity to pro-oxidant agents.

This paper presents the results of the electromagnetic analyses of the ITER vacuum vessel and blanket modules. A wide collection of electromagnetic transients has been simulated: VDEs and MDs belonging to cat III, II and I, and a magnet fast discharge. Eddy and halo currents and corresponding Lorentz forces have been computed using 3D solid FE models implemented in ANSYS and CARIDDI. The plasma equilibrium configurations (displacement and quench of the plasma current, toroidal flux variation due to the β drop and halo currents wetting the first wall) used as an input for the EM analyses have been supplied by the 2D axisymmetric code DINA. The paper describes in detail the methodology used for the analyses and the main results obtained.

The neutral beam heating and current drive system in ITER consists of 3 beam lines (2 present plus one future upgrade) with each beam line designed to deliver 40 A of accelerated deuterium beams at 1 MeV with a 25% duty cycle. The beam line is coupled to the vacuum vessel port of the tokamak through a series of front end components and a connecting duct. The edge of the beam line and the walls of the vacuum vessel up to the blanket aperture are lined with duct liners to protect them from heat loads from the direct and re-ionised beam interception during the transport of the neutral beam. The direct interception of the beam is due to the inherent divergence of the beam or its halo component. The re-ionised beam consists of ions born due to the interaction of the accelerated neutral beam with the back ground gas all along the beam line, after the neutraliser exit. The motion of these ions is also affected by the electric field of the residual ion dump (RID) and the magnetic field from the tokamak during its various phases of operation. A systematic study to assess the heat loads during the neutral beam transport on the different front end components, the various regions of the duct and the blanket modules is necessary to ascertain the proper thermo-mechanical design of these components. The beam transmission code "BTR" has been used for that purpose. Simulations have been carried out of the gas profile along the neutral beam line considering gas flux from the ion source, the neutraliser, the RID (due to the dumped ion beams) and the flow of the gas from the tokamak to the duct. The re-ionisation losses have been estimated to be 13.8 % for the region between the exit of the neutraliser and the blanket module edge. The magnetic fields for the various operating scenarios of the tokamak like the start of the burn (SOB), end of burn (EOB), X point formation (XPF), XPF + 20 s, EOB + disruption have been simulated for the 15 MA DT scenario. The beamlet divergence has been considered to range between 3 - 7 mrad for the main beam component and 30 mrad for the halo fraction which has been taken as 15% of the main beam. The simulations have been performed for the neutral beam axis vertical inclination of 49 mrad with an additional 10 mrad vertical tilt, which is required for off-axis current drive and avoidance of beam excited toroidal Alven eigenmodes in the ITER plasma. The results of these simulations will be presented and discussed.

In order to evaluate the free radical defense systems of melanocytes and their possible correlation with melanoma, we have studied in cultured normal human melanocytes (20), normal melanocytes from melanoma patients (15), and melanoma cells (40) the fatty acid pattern of membrane phospholipids as a target of peroxidative damage and the superoxide dismutase and catalase activities, vitamin E, and ubiquinone levels as intracellular antioxidants. Cells were cultured in the same medium and analyzed at III or IV passage. Compared to the values obtained in normal human melanocytes, melanoma cells showed on average: a) higher levels of polyunsaturated fatty acids, b) increased superoxide dismutase and decreased catalase activities, higher vitamin E, and lower ubiquinone levels. Among the normal melanocytes from melanoma patients studied, two groups were differentiated: a) cultures (7) with enzymatic and non-enzymatic antioxidants level similar to those of normal human melanocytes; b) cultures (8) with antioxidant patterns similar to those observed in melanoma cells. Polyunsaturated fatty acids were also increased hi the latter group. The results indicate that in melanoma cells and in a percentage of normal melanocytes from melanoma patients, an imbalance in the antioxidant system can be detected that can lead to endogenous generation of reactive oxygen species and to cellular incapability of coping with exogenous peroxidative attacks. These alterations could be correlated with the malignant transformation of cells and with the progression of the disease.

Hypomelanosis of Ito (HOI) is a multisystem neurocutaneous disorder. In the described cases, cutaneous manifestations (unilateral or bilateral streaks and swirls of hypomelanosis with regular and confluent borders) and extracutaneous abnormalities are often associated. Extracutaneous abnormalities involve the musculoskeletal system (scoliosis, vertebral anomalies, cranial-facial malformations) and other organs, as well as the central nervous system (CNS). The most significant anomalies of the CNS are psychomotor retardation and cognitive deficit. Autism, epilepsy, language disorders, cerebral malformations (neural migration disorders, cerebral hypoplasia, cortical atrophy, agenesis of the corpus callosum) are sometimes present. Numerous abnormal chromosomal patterns have been observed. HOI is usually a sporadic disorder; though autosomal dominant transmission has been suggested, recessive and X-linked inheritance patterns have also been reported. This study describes five children with HOI presenting with various features of the clinical spectrum of the syndrome. Some of these cases were referred for psychomotor therapy as part of an integrated neuropsychologic and psychomotor treatment support program. In this view, psychomotor treatment aims to promote the emotional-relational component, to overcome rigid divisions, and to integrate learning-related cognitive aspects with psychodynamic concepts. Finally, the goals of psychological and social support are to help the parents accept their child's handicap, understand the child's behavior, plan future pregnancies, and foster an environment for their child's integration.

Creativity represents the silent character of human behaviour. In children with epilepsy, cognitive performance of has mainly been investigated under the assumption that the disorder represents a risk factor for the development of intellectual function. In subjects with different forms of epilepsy, neuropsychologic disorders have been detected even when cognitive-global functioning is unimpaired. The cognitive functions of subjects with epilepsy have been widely studied, but their creativity has been never evaluated to date. The aim of this study was to describe the development of creative thinking in a group of children with absence epilepsy.The test battery included: the Torrance Test of Creative Thinking (TTCT), the Wechsler Intelligence Scale for Children-revised (WISC-R) and the Goodenough Human Figure Drawing Test.Statistical analysis (Mann-Whitney test) showed a statistically significant difference (P0.05) in test scores between two groups of subjects (children with epilesy vs control group), with higher scores for figure originality, figure fluidity and figure elaboration in the control group. There was a significant correlation (Spearman's rho) between verbal IQ and verbal fluidity and verbal flexibility subscale scores and between performance IQ and figure elaboration, between total IQ and verbal fluidity and verbal flexibility subscales (P0.05; r0.30).Low scores on the figure originality subscales seem to confirm the hypothesis that adverse psychodynamic and relational factors impoverish autonomy, flexibility and manipulator interests. The communication channels between subjects with epilepsy and their family members were affected by the disorder, as were the type of emotional dynamics and affective flux.

The ITER [1] fusion device is expected to demonstrate the feasibility of magnetically confined deuterium–tritium plasma as an energy source which might one day lead to practical power plants. Injection of energetic beams of neutral atoms (up to 1 MeV D0 or up to 870 keV H0) will be one of the primary methods used for heating the plasma, and for driving toroidal electrical current within it, the latter being essential in producing the required magnetic confinement field configuration. The design calls for each beamline to inject up to 16.5 MW of power through the duct into the tokamak, with an initial complement of two beamlines injecting parallel to the direction of the current arising from the tokamak transformer effect, and with the possibility of eventually adding a third beamline, also in the co-current direction. The general design of the beamlines has taken shape over the past 17 years [2] , and is now predicated upon an RF-driven negative ion source based upon the line of sources developed by the Institute for Plasma Physics (IPP) at Garching during recent decades [3] , [4] , [5] , and a multiple-aperture multiple-grid electrostatic accelerator derived from negative ion accelerators developed by the Japan Atomic Energy Agency (JAEA) across a similar span of time [6] , [7] , [8] . During the past years, the basic concept of the beam system has been further refined and developed, and assessment of suitable fabrication techniques has begun. While many design details which will be important to the installation and implementation of the ITER beams have been worked out during this time, this paper focuses upon those changes to the overall design concept which might be of general interest within the technical community.

Fusion for energy (F4E), the European Domestic Agency for ITER, is involved in a relevant number of activities in the area of electromagnetic analysis in support of ITER general design, and of specific requirement of the EU in-kind procurement. In this context, its main activity is linked with the electromagnetic analysis of several ITER components (blanket shield modules and first wall panels, blanket cooling manifolds. TBM port plug, etc.) subjected to electro-dynamical loads. Another important activity is related to the ITER superconducting magnets, namely the quench detection of the ITER TF coils and the joule losses in the magnets cold structures. Last, but not least, a further activity is on going on the error field analysis due to tolerances in both construction and assembly of ITER magnets. (C) 2011 Elsevier B.V. All rights reserved.

Profile consistency based on the parallel component of Ohm's law has been used to obtain electron temperature profiles. A resistive neoclassical term and a term that accounts for the bootstrap current contributions have been considered in Ohm's law. A numerical code has been developed to find solutions according to the MHD equilibrium equations. For stationary plasmas, the temperature profiles, obtained by a procedure in which a pseudo-parabolic shape of (J/R) is assumed and the peak temperature known from experiments is used, are close to the experimental data for several very different machines (JET, TFTR, ASDEX, ALCATOR-C and FT). The main feature of the model is its capability to provide an easy parametrization of Ohm's law also in nonstationary cases, without going through the complication of a detailed solution of the magnetic field diffusion equation. A rule for estimating a maximum value of the current diffusion time inside the plasma volume in such situations is given. This rule accounts for both the temperature profiles and the stabilization times in some nonstationary pulses observed in JET

Quality of life is increasingly the focus of attention by health, psychological and social services. Pervasive developmental disorders (PDD) are a group of psychiatric conditions in which the patient's clinical case history is characterized by disturbances in social interaction, deterioration of verbal and non-verbal communication, and presence of bizarre, limited and stereotyped activity. These disturbances affect multiple developmental areas and show up in very early stages of development, resulting in a permanent disorder. Many studies have sought to recognize causes and interventions for persons with PDD, however, they often take insufficient account of the effects these disorder can have on the lifestyle of patients and their families. These clinical case histories are so pervasive that they cause a disorder which upsets the equilibrium of the person's entire life. The aim of this study was to assess the effect of living with PDD on the person's quality of life and to highlight the factors that impact on the person and his/her family.Both parents of 54 subjects (46 males and 8 females; age range 4-28 years) with diagnosed PDD (43 with autistic disorder, 2 with childhood disintegrative disorder, 3 with Asperger Syndrome, 6 with pervasive development disorder NAS) were enrolled in the study. The subjects affected with PDD were recruited at the AGSAS Onlus and IsMeC. Diagnosis was based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders. Quality of life was assessed using the Italian version of the Impact of Childhood Illness Scale (Hoare and Russell, 1995). This scale consists of 30 questions that investigate the effect of illness on children, parents and families. For each question, the parent was asked to rate two variables: frequency and importance. Another questionnaire was administered to obtain medical history, diagnostic and therapeutic data of the persons with PDD.Analysis of frequencies and percentages of questionnaire answers showed that the most important problems related to illness; specifically, according to the Frequency and Importance Parameters, the problems centered around self-care skills, difficulty in explaining the child's illness to others and looking after the child. The most important problems about the other children in the family concerned providing them with necessary attention and the restrictions their brother/sister's illness placed on their own activities. No significant correlations emerged between diagnosis type and answers on individual subscale items (Pearson's r).Our data show that PDD has a considerable impact on both the child's development and the entire family. Parents' answers demonstrated that their child's illness had consequences for the child and how the family coped with it. For this reason, attention should be directed at psychological and social aspects, as well as attitudes, manners, reactions and effects such disturbances can have on the entire family.

To contribute to a better understanding of the role of chromosomal rearrangements in the tumorigenesis of uveal melanoma, we present a case in which a structural aberration of chromosome 3 could indicate the specific region in which an uveal melanoma tumor suppressor gene could be located. We obtained a primary cell culture, characterized by cytogenetic study, through GTG- and CBG-banding techniques by using a mechanical dissection of a tumor sample obtained from an uveal melanoma. Cytogenetic analysis performed in the primary cell culture highlighted the presence of a structural rearrangement involving chromosomes 3 and 22. A t(3;22)(p13;p11) was observed as the only present clonal aberration. The 3p13 breakpoint involved in the aberration observed in our case could be essential in restricting the candidate region for the locus of an uveal melanoma tumor suppressor gene located on chromosome 3.

Since the 1950s, the problem of how to evaluate creativity has been addressed in studies on the definition of measurement criteria and on the relationship between intelligence and creative thinking. Many revealed cognitive and relational disorders in preterm infants, particularly in preterm very low birth weight infants (birth weight1500 g) and in infants with serious complications. This study describes the development of creative thinking in a group of children born preterm.The study sample was 43 children (21 males, 22 females; age range 6-11 years), regularly attending school, born with low birth weight (1050-2450 g) at 29-32 weeks gestational age, and compared with a control group with birth weight2500 g. The test battery included: Torrance Test of Creative Thinking (TCTT); WISC-R intelligence test; Goodenough Human Figure Drawing Test.Statistical analysis (Mann-Whitney U test) showed a statistically significant difference (P0.05) between the 2 groups; scores for figure originality, figure fluidity and figure elaboration were consistently higher in the control group. Within the low birth weight group, there was a significant correlation (Spearman r) between verbal IQ and verbal fluidity and verbal flexibility subscale scores and between IQ performance and figure elaboration. Scores on the figure drawing tests showed higher creative ability in the control group.In children born preterm with low birth weight, emotive dynamics and flow of affection may influence the channels of communication between child and family. The low figure originality subscale scores support the hypothesis that psychodynamic and relational factors (worry about the preterm condition, overprotective behaviour by parents and others) could lead to diminished autonomy, flexibility and manipulatory interest in the child.

Maternal hyperphenylalanemia during pregnancy may induce a severe embryopathy characterized by microcephaly, mental retardation, facial dysmorphy and congenital heart defects. Four subjects, two pairs of sibs, with maternal hyperphenylalaninemia syndrome were included in this study and their neuropsychological performances were assessed. Maternal levels of hyperphenylalaninemia were similar in both mothers, one of them had not been diagnosed with the condition until her two children were examined at the ages of 10 and 6 years. A severe cognitive deficit was detected in all 4 subjects, with a typical profile of impaired perceptive abilities, behavioural disturbances, motor difficulties and poor familiar integration.

The aim of this study was to explore some fundamental dimensions of adolescent discomfort relating to food, the body, sexuality, relationships in general and health care.We recruited 206 students (66 males, 140 females; average age=19.4+/-2) and we administered 4 questionnaires: the first two to examine their relationship with food, the third to explore adolescents' attitudes to their social context, sexuality and first sexual experiences; the fourth to measure their ability to look after their health.The results show the different role that sexual styles have in the expression of juvenile discomfort. Girls tend to live the discomfort by mentalizing it in relationships and sexuality and contextualizing it in their bodies; boys direct their discomfort towards occasional drug taking or drug addiction, or alcohol abuse, the excitement of speed, or dangerous driving.In clinical work with adolescents it seems appropriate to refer to the relational gradient of risk behaviours, that is their linking function within their peer group. Behaviours with a high relational gradient, which develop within the group or are related to the group, in most cases are normal modalities for facing the important challenges of adolescence. These behaviours are symptoms of the normal process of adolescent development. We should pay particular attention to behaviours with a low relational gradient because they indicate a possible interruption in their development.

The ITER divertor design, as originally conceived, required further optimisation to overcome the critical issue still remaining after the first assessment and to reduce the redundancies of some feature. In particular, the analyses carried out on the cassette body (CB) and the divertor plasma facing component (PFC) showed substantially high stress due both to thermal and fast-vertical displacement event (VDE) loads to be reduced by modifying the attachment system and making provisions for reducing the electromagnetic loads (EM). On the other hand, it has been demonstrated that a large margin exist in the shielding capability of the proposed design as well as in the required stiffness of the CB. The reduction of the CB thickness allow for a reduction of the thermal stresses. The design revision required many scope analyses to find the best configuration from the EM standpoint, neutronic analysis to assess the minimum shield thickness and a thermal-mechanical analysis on the modified attachment system. The results of the new set of analyses show the soundness of the modified divertor system.

Risk behaviours--as they are defined by specialist literature for the damage these behaviours cause to young people's health and/or life--are getting more and more frequent among young people. They range from self-injuring behaviours to the consequences of a precocious, high-risk and/or promiscuous sexual activity, from abnormal eating behaviours to the deaths from fun.The inquiry concerned a group of university students (100 males and 100 females), selected at random from the Faculties of Medicine and Surgery, Psychology, Economy and Jurisprudence of the University of Palermo, who were asked to answer a questionnaire composed of 91 questions and structured in 4 sections. The first section regards associate-identifying information; the second one inquires on experiences and requirements concerning sexuality; the third section explores the state of health and the use of drugs and alcohol; the fourth section looks into relations with others.The analysis of our data revealed that young people have different high-risk behaviours (use of drugs and alcohol, non protected sexual intercourse, carelessness for one's and one's partner's serological state); this is associated to poor information, as complained by the people interviewed, on the prevention of sexually transmissible diseases, use of drugs and alcohol.The conclusion is drawn that the new modalities of the assumption of risk by young people would correspond to the climate of vagueness, lack of limits, meanings and values which characterize the present society.

Aim. We considered the spreading and the increasing of aggressive and violent behaviours. The most of them have two common roots: lack of actual motivation and brutality. Our research intends to detect specific indicators and predictive signs of violent and aggressive behaviours. In order to this, scientific literature shows that the most reliable indicators and predictive signs are linked to structural personality features (e.g. defensive strategies, impulse control). Methods. This cross sectional study compares a group of 26 male adolescents with Conduct Disorder (F91.8), a group of 29 male patients with Borderline Personality Disorder (F60.31) and a group of 33 male prisoners with Antisocial Personality Disorder (F60.2). The protocol includes: the Structured Clinical Interview for DSM-IV Axis II Disorders (for the recruitment of adult groups); the Indicators of Aggressive Conduct and the Profile of Mood States (for the recruitment of the adolescent group); the Defense Mechanisms Inventory. Results. The performances of the groups about their predominant defensive strategies and starting emotional background are significantly different. Conclusions. We selected a profile where low emotional response supports aggressiveness and a profile where aggressiveness and violence are associated with “clinically significant” impulsivity. Therefore, on one hand this study allows us to detect some indicators and clinical predictors of aggressiveness and violence, on the other hand we identified the most risky profiles according to used instruments.