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The International Thermonuclear Experimental Reactor (ITER) is the next step toward the realization of electricity-producing fusion power plants, and it is planned to be in operation in 2016. ITER has been designed so as to reach the plasma burning condition and to operate with high-elongated unstable plasmas. However, due to the constraints that affect the machine realization, these open-loop unstable high-performance plasmas can hardly be stabilized using the poloidal field coils placed outside the tokamak vessel. For this reason, during the ITER design review phase, it has been proposed to investigate the possibility of using in-vessel coils in order to improve the best achievable performance of the vertical stabilization (VS) system. This paper proposes a new approach for the plasma current, position, and shape control design in the presence of in-vessel coils. Two control loops are designed: a first loop that guarantees the VS driving the voltage applied to in-vessel coils, and a second loop that controls the plasma current and up to 32 geometrical shape descriptors as close as possible to the reference values. The performance of the proposed control system is shown by means of simulations of some cases of interest. Index Terms--Plasma shape control, plasma vertical stabilization (VS), tokamaks control.

The high-energy ionized particles collected by the divertor structures in a tokamak reactor cause a localized thermal load around the strike-points, which are the intersections of the separatrix with the divertor tiles. To spread on a larger region this thermal load, it is convenient to resort to a sweeping, i.e., a periodical movement of the strike-points. This paper introduces the new model-based sweeping algorithm recently implemented on the Joint European Torus tokamak, within the eXtreme Shape Controller architecture. Index Terms--Plasma-shape control, plasma strike-point sweeping, tokamaks control.

This paper describes a set of graphic tools for the design and validation of the new plasma shape controller [eXtreme Shape Controller (XSC)], which has been recently implemented at the Joint European Torus tokamak. The XSC enables operation with high elongation and high triangularity plasmas. The software suite, which is called XSC Tools, has been developed to automate the design procedure of the XSC. These tools make use of graphic user interfaces to allow the nonspecialist users to prepare for new operative scenarios, without the help from modeling and control specialists. Once a new controller is generated, all its parameters are saved into a text file, which is used to perform the validation of the scenario via simulations. The same file is then loaded by the real-time code running on the plant, without any further processing. This feature guarantees that the controller, which is running on the plant, is exactly the same one validated through simulations. An additional effort has been made in order to make the XSC Tools machine independent, i.e., to enable their use on the different tokamaks. Index Terms--Control-system validation, software tools, tokamak control.

We focus on the estimation of the minimum poloidal field coil voltages for the plasma shape control in a tokamak. For given coil locations and for a class of disturbances we propose a procedure for the evaluation of the minimum voltages needed to guarantee that the plasma boundary displacement remains within specified limits. The impact of this problem on the minimization of the power supply cost is discussed for the case of the International Thermonuclear Experimental Reactor (ITER). Index terms - Optimization, plasma control, power supplies, tokamaks, electromagnetic fields, finite element methods.

The treatment of segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons. Open tibia and ankle fractures occur with an incidence of 3.4 per 100,000 and 1.6 per 100,000, respectively [[1]] and have a high propensity to lead to the development of fracture-related infection with associated chronic osteomyelitis. However, compared to the more commonly used technique of bone transport with external fixation, no complications (including non-union, stress, or refracture at the bone regeneration site or pin tract infections) have been observed. [Extracted from the article]

The plasma control system (PCS) in a tokamak device is in charge of controlling the evolution of plasma parameters according to prescribed models against uncertainties and disturbances. The PCS accomplishes its mission by receiving data from the diagnostics and by computing in real-time the commands to the actuators that affect the plasma behavior. The design of the ITER PCS includes many different aspects, which are not limited to the design of control algorithms, including the definition of the verification and validation tests for various components and commissioning procedures. Moreover, contributions come from different parties that adopt heterogeneous sources. To homogenize these contributions and to keep track of the PCS life-cycle throughout various design stages, a specific system-engineering approach has been adopted on top of the standard ITER life-cycle and the requirement management process. Such an approach relies on a database (DB) implemented using Enterprise Architect that allows modeling various aspects of the PCS design using SysML. This article gives an overview of the adopted approach and describes the structure and the current content of the PCS DB. [ABSTRACT FROM AUTHOR]

This paper proposes an approach aimed at avoiding or mitigating the consequences of a plasma disruption in a tokamak. The control strategy is based on a Disruption Predictive Control (DPC) where the use of a set of disruption predictors could allow actively modification of some plasma parameters when a disruption warning is issued. The DPC approach requires the continuous monitoring of various plasma performance indicators, which play the role of disruption precursors. The active control is based on the availability of magnetic and nonmagnetic plasma parameter response models as well as multivariable control algorithms and architectures. [ABSTRACT FROM AUTHOR]

A criticism of the book "Giustizia e garanzie giurisdizionali: Appunti di storia degli ordinamenti giudiziari," by Paolo Alvazzi del Frate is presented. An analysis of the relationship between history and law in France and in Italy as well as how they parallel one another during the Napoleonic period is examined.

Tokamaks are the most promising approach for nuclear fusion on earth. They are toroidal machines where the plasma is heated in a ring-shaped vessel and kept away from the vessel by applied magnetic fields. To achieve high performance in tokamaks, plasmas with elongated poloidal cross-section are needed. Such elongated plasmas are vertically unstable, hence position control on a fast time scale is clearly an essential feature for all tokamak devices. In this context the Plasma Control Upgrade project was aimed at increasing the capabilities of the Vertical Stabilization (VS) of the JET tokamak. This paper introduces the new JET VS system and focuses on how the flexibility of this real-time system has been exploited to enlarge its operational limits in terms of maximum controllable disturbance. Eventually, some experimental results achieved during the last experimental campaigns are presented. [ABSTRACT FROM PUBLISHER]

The achievement of the required performances during the operation of large fusion experimental reactors, is strictly related to the flexibility and reliability of the real-time infrastructures. It turns out that, in tokamak reactors, the real-time infrastructure has to be designed so as to meet a number of common requirements. An overview of the real-time infrastructure currently adopted at the JET tokamak is given in this paper, focusing the attention on the solutions that have been developed for addressing these common requirements. Furthermore, three real-time systems recently deployed at JET are described as example. [ABSTRACT FROM PUBLISHER]

The ITER tokamak (Latin for "the way") is the next step toward the realization of electricity-producing fusion power plants, since it has been designed to reach the plasma burning condition. The Central Safety System for Nuclear Risk (CSS) is the control system in charge to assure nuclear safety for the ITER plant, the personnel, and the environment. Since the CSS is a critical safety system, its validation and commissioning play an important role, and the required level of reliability must be demonstrated. In such a scenario, it is strongly recommended to use modeling and simulation tools since the early design phase. Indeed, mathematical models will help in the definition of the control system requirements. These models can be used for the rapid prototyping of the safety system, and hardware-in-the-loop (HIL) simulations can be performed to assess the performance of the control hardware against a plant simulator. This paper introduces the methodology and the software/hardware architecture used to develop both a CSS prototype and a ITER plant model suitable for the test and validation of this prototype. [ABSTRACT FROM AUTHOR]

Abstract-This paper describes the design and the experimental validation of a multivariable current and shape controller for the Joint European Torus (JET) tokamak. Using this new controller, physicists have been able to carry out experiments where accurate control of the plasma boundary is needed. From a control point of view, the problem has been formulated as an output regulation problem for a linear time-invariant (LTI) plant whose controllable outputs are more than the control inputs. For the case of constant references, we propose a control scheme that minimizes a quadratic cost function. This cost function weights the tracking error at steady state. Our methodology is based on the singular value decomposition of the static gain matrix of the plant. In the controller design, we can also take into account the steady-state control effort. The proposed controller has been implemented and tested on the plant; some experimental results are included in this paper. The activity that has been carried out and that is described in this paper is relevant in the perspective of the new experimental reactor ITER. [ABSTRACT FROM AUTHOR]

Describes the design and experimental validation of a multivariable digital controller for a Tokamak. Linearized model of the plasma confined in a Tokamak; Scope of the controller; Nested loops composing the proposed controller; Improvement of the performance with respect to those obtained with a proportional integral derivative.

Presents an approach for the design of a plasma current and shape feedback control system in a Tokamak. Enlargement of the operating envelope in which the Tokamak can operate without current saturation; Properties of the two feedback loops that comprise the proposed controller structure.

Radon, a radioactive inert gas that comes from the decay of naturally occurring radioactive species, poses a substantial health risk due to its involvement in lung cancer carcinogenesis. This work proposes a metrological approach for determining radon exhalation rates from diverse building materials. This methodology employs an electrostatic collection chamber for alpha spectrometry of radon isotopic decay products. Experimental evaluations were conducted particularly focusing on volcanic gray tuff from Sant'Agata de' Goti (Campania region, Italy), a material commonly utilized in construction, to assess radon exhalation rates. The study aligns with Legislative Decree 101/2020, a transposition of European Directive 59/2013/Euratom, highlighting the need to identify materials with a high risk of radon exhalation. Moreover, this work supports the goals of the Italian National Radon Action Plan related to the aforementioned decree, aiming to develop methodologies for estimating radon exhalation rates from building materials and improving radioprotection practices. [ABSTRACT FROM AUTHOR]

Background: Several evidence demonstrated that glucagon-like peptide 1 receptor agonists (GLP1-RAs) reduce the risk of dementia in type 2 diabetes patients by improving memory, learning, and overcoming cognitive impairment. In this study, we elucidated the molecular processes underlying the protective effect of Tirzepatide (TIR), a dual glucose-dependent insulinotropic polypeptide receptor agonist (GIP-RA)/ GLP-1RA, against learning and memory disorders. Methods: We investigated the effects of TIR on markers of neuronal growth (CREB and BDNF), apoptosis (BAX/Bcl2 ratio) differentiation (pAkt, MAP2, GAP43, and AGBL4), and insulin resistance (GLUT1, GLUT4, GLUT3 and SORBS1) in a neuroblastoma cell line (SHSY5Y) exposed to normal and high glucose concentration. The potential role on DNA methylation of genes involved in neuroprotection and epigenetic modulators of neuronal growth (miRNA 34a), apoptosis (miRNA 212), and differentiation (miRNA 29c) was also investigated. The cell proliferation was detected by measuring Ki-67 through flow cytometry. The data were analysed by SPSS IBM Version 23 or GraphPad Prism 7.0 software and expressed as the means ± SEM. Differences between the mean values were considered significant at a p-value of < 0.05. GraphPad Prism software was used for drawing figures. Results: For the first time, it was highlighted: (a) the role of TIR in the activation of the pAkt/CREB/BDNF pathway and the downstream signaling cascade; (b) TIR efficacy in neuroprotection; (c) TIR counteracting of hyperglycemia and insulin resistance-related effects at the neuronal level. Conclusions: We demonstrated that TIR can ameliorate high glucose-induced neurodegeneration and overcome neuronal insulin resistance. Thus, this study provides new insight into the potential role of TIR in improving diabetes-related neuropathy. [ABSTRACT FROM AUTHOR]

For the first time, a map of the 222Rn gas has been produced in the Campania region, the southern part of Italy, based on the activity concentration measured in indoor environments. This work is part of the radon mitigation policy and complies with the recent Italian Legislative Decree 101/2020, which implements the European Basic Safety Standards, Euratom Directive 59/2013, where Member States must declare areas with elevated levels of indoor radon concentration. The obtained map, divided by Campania municipalities, identifies priority areas with activity concentration values exceeding the reference level of 300 Bq m–3. In addition, an effective statistical analysis of the dataset has been carried out. [ABSTRACT FROM AUTHOR]

STING is a transmembrane ER resident protein that was initially described as a regulator of innate immune response triggered by viral DNA and later found to be involved in a broader range of immune processes. Here, we assessed its role in the antigen presentation by generating a STING KO macrophage cell line. In the absence of STING, we observed an impaired OVA-derived SIINFEKL peptide presentation together with a decreased level of MHC-I complex on the plasma membrane, likely due to a decreased mRNA expression of β2 m light chain as no relevant alterations of the peptide-loading complex (TAPs) were found. Moreover, JAK-STAT signaling resulted in impaired STING KO cells following OVA and LPS treatments, suggesting a dampened activation of immune response. Our data revealed a new molecular role of STING in immune mechanisms that could elucidate its role in the pathogenesis of autoimmune disorders and cancer. [ABSTRACT FROM AUTHOR]

The JET Shape Controller (SC) uses nine distinct circuits, powering the JET poloidal field coils, to control in real time the coil currents, and the plasma shape, current and position. The control scheme presently used [1] is based on a Multiple Input Multiple Output (MIMO) controller, which is designed to decouple the inductive coupling of the different coils. Achieving such a decoupling, the SC allows the user to tune independently the time response of each circuit. As a matter of fact the intended decoupling algorithm has been incorrectly coded in the JET SC system. This paper describes the modelling and experimental activities performed to correct the code error, and to improve the performance on a subset of the controlled parameters. [ABSTRACT FROM AUTHOR]

The table of contents for the December 1, 2009 issue of "Genome" is presented.

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