Verbal and non-verbal recognition memory assessment: validation of a computerized version of the Recognition Memory Test

Background: The use of computerized devices for neuropsychological assessment (CNADs) as an effective alternative to the traditional pencil-and-paper modality has recently increased exponentially, both in clinical practice and research, especially due to the pandemic. However, several authors underline that the computerized modality requires the same psychometric validity as "in-presence" tests. The current study aimed at building and validating a computerized version of the verbal and non-verbal recognition memory test (RMT) for words, unknown faces and buildings. Methods: Seventy-two healthy Italian participants, with medium-high education and ability to proficiently use computerized systems, were enrolled. The sample was subdivided into six groups, one for each age decade. Twelve neurological patients with mixed aetiology, age and educational level were also recruited. Both the computerized and the paper-and-pencil versions of the RMT were administered in two separate sessions. Results: In healthy participants, the computerized and the paper-and-pencil versions of the RMT showed statistical equivalence for words, unknown faces and buildings. In the neurological patients, no statistical difference was found between the performance at the two versions of the RMT. A moderate-to-good inter-rater reliability between the two versions was also found in both samples. Finally, the computerized version of the RMT was perceived as acceptable by both healthy participants and neurological patients at System Usability Scale (SUS). Conclusion: The computerized version of the RMT can be used as a reliable alternative to the traditional version

Cylindrical Model of RWM in RFP Plasmas and Application on RFX-mod

The RWM instabilities have been demonstrated to be successfully controlled by the feedback equipment implemented in the experiments of RFX-mod Apart from some similar behaviour in both RFP and Tokamak configurations, the RWMs in RFP plasmas are current driven instabilities; while in Tokamak the RWMs are normally driven by the plasma pressure. Furthermore, in RFPs the external kink instabilities, having their rational surfaces outside the plasma, exist as so called externally non-resonant modes (ENRM),which have their rational surfaces located at q < q(a) <0 (q(a) is the safety factor at the plasma edge); and internally non-resonant modes (INRM) with rational surfaces corresponding to q > q(0) > 0. This fact leads to a more severe condition on the stabilization by plasma rotation and dissipation. In addition, the current driven RWM instability in a RFP, where the strong poloidal magnetic field leads to a "bad curvature" dominant along the entire poloidal angle, has much weaker ballooning structure than in a tokamak. In the present work, we study RWM instabilities in cylindrical RFP plasmas by MHD theory, in which the effects of the plasma pressure, compressibility, plasma inertia, longitudinal rotation and parallel viscosity (tensor) have been taken into account. The resistive wall is modeled with a finite thickness, which allows to treat a large equilibrium flow in the plasma and ωτ b >>1 (ω is the mode frequency and τ b is the wall penetration time scale length). In the RFP configuration the poloidal asymmetry in the equilibrium magnetic field is much weaker than in a tokamak, the existing studies in toroidal geometry of RFPs have shown a weak influence of the toroidal coupling effects on the growth rate of the RWM modes I. RFP equilibrium and eigenmode equation. Considering a cylindrical plasma with minor radius r=a, surrounded by a resistive wall at r=b with thickness h and conductivity σ, an

A Key to Improved Ion Core Confinement in the JET Tokamak: Ion Stiffness Mitigation due to Combined Plasma Rotation and Low Magnetic Shear

New transport experiments on JET indicate that ion stiffness mitigation in the core of a rotating plasma, as described by Mantica et al. Phys. Rev. Lett. 102 175002 (2009)] results from the combined effect of high rotational shear and low magnetic shear. The observations have important implications for the understanding of improved ion core confinement in advanced tokamak scenarios. Simulations using quasilinear fluid and gyrofluid models show features of stiffness mitigation, while nonlinear gyrokinetic simulations do not. The JET experiments indicate that advanced tokamak scenarios in future devices will require sufficient rotational shear and the capability of q profile manipulation. © 2011 American Physical Societ