MagnetoEncephaloGraphy (MEG) and ElectroEncephaloGraphy (EEG) are the most common non-invasive brain imaging techniques for monitoring the electrical brain activity with millisecond resolution. Due to their high, millisecond, temporal resolution, these techniques are also the most suitable for studying the dynamic interplay of between brain regions during information processing. In clinical settings, MEG and EEG are valuable methods for the pre-surgical evaluation of patients with pharmaco-resistant epilepsy. The localization of epileptogenic zone (EZ) provided by these techniques can avoid or guide invasive intracranial recordings. More recently, there is has been a growing interest in exploiting leveraging these techniques as a crucial tool to advance our understanding of the pathophysiological mechanisms of major neuropsychiatric disorders and neurological diseases.
This symposium offers an overview of very recent studies on the use ofwhich employed MEG and EEG as valid tools to investigate brain disorders. In particularSpecifically, the five talks will provide important insights on new methodological approaches to characterize brain dysfunctions in different pathological conditions. We will focus on : (1) emerging tool to characterize irritative zones in epileptic patients and to detect in a semi automatic way epileptiform abnormalities during EEG sleep recordings ina semi-automatic way; (2) two different methodological approaches to evaluate frequency specific alterations of brain activity and connectivity in schizoprenia and glioma patients; and (3) using machine-learning methods for identificationto identify EEG predictors of dementia in Parkinson.
2021Presentazione / Comunicazione non pubblicata (convegno, evento, webinar...)metadata only access
An in-vivo comparison of source localization methods
Annalisa Pascarella
;
Ezequiel Mikulan
;
Federica Sciacchitano
;
Simone Sarasso
;
Annalisa Rubino
;
Ivana Sartorie
;
Francesco Cardinale
;
Flavia Zauli
;
Pietro Avanzini
;
Lino Nobili
;
Andrea Pigorini
;
Alberto Sorrentino
Electrical source imaging (ESI) aims at reconstructing the electrical brain activity from measurements
of the electric field on the scalp. ESI is a key element in the analysis of EEG data, in both research and
clinical settings.
In the last twenty years several algorithms have been applied for solving the ill- posed EEG inverse
problem. Most of these popular methods can be derived within a Bayesian statistical framework in
which all variables can be modelled as random variables with associated probability density functions
(pdf) and the solution of the inverse problem is the posterior pdf for the unknown primary current
distribution conditioned on the measurements. The different methods mainly differ from each other
by the quality and quantity of a priori information they use in order to solve the EEG inverse problem.
In this study [1] we validate and compare ten different ESI methods (wMNE, dSPM, sLORETA, eLORETA,
LCMV, dipole fitting, RAP-MUSIC, MxNE, gamma map and Sesame) "in vivo", by exploiting a recently
published EEG dataset [2] for which the ground truth is known. We compare the different inverse
methods under multiple choices of input parameters, to assess the accuracy of the best
reconstruction, as well as the impact of the parameters on the localization performance
Single cell multi-omic analysis identifies a Tbx1-dependent multilineage primed population in murine cardiopharyngeal mesoderm.
Nomaru H
;
Liu Y
;
De Bono C
;
Righelli D
;
Cirino A
;
Wang W
;
Song H
;
Racedo SE
;
Dantas AG
;
Zhang L
;
Cai CL
;
Angelini C
;
Christiaen L
;
Kelly RG
;
Baldini A
;
Zheng D
;
Morrow BE
The poles of the heart and branchiomeric muscles of the face and neck are formed from the cardiopharyngeal mesoderm within the pharyngeal apparatus. They are disrupted in patients with 22q11.2 deletion syndrome, due to haploinsufficiency of TBX1, encoding a T-box transcription factor. Here, using single cell RNA-sequencing, we now identify a multilineage primed population within the cardiopharyngeal mesoderm, marked by Tbx1, which has bipotent properties to form cardiac and branchiomeric muscle cells. The multilineage primed cells are localized within the nascent mesoderm of the caudal lateral pharyngeal apparatus and provide a continuous source of cardiopharyngeal mesoderm progenitors. Tbx1 regulates the maturation of multilineage primed progenitor cells to cardiopharyngeal mesoderm derivatives while restricting ectopic non-mesodermal gene expression. We further show that TBX1 confers this balance of gene expression by direct and indirect regulation of enriched genes in multilineage primed progenitors and downstream pathways, partly through altering chromatin accessibility, the perturbation of which can lead to congenital defects in individuals with 22q11.2 deletion syndrome.
A recently proposed mesoscale approach for the simulation of multicomponent flows with near-contact interactions is employed to investigate the early stage formation and clustering statistics of soft flowing crystals in microfluidic channels. Specifically, we first demonstrate the ability of the aforementioned mesoscale model to accurately reproduce main mechanisms leading to the formation of two basic droplet patterns (triangular and hexagonal), in close agreement with experimental evidence. Next, we quantitatively evaluate the device-scale clustering efficiency of the crystal formation process by introducing a new orientational order parameter, based on the Delaunay triangulation and Voronoi diagrams analysis of the droplet patterns. The mesoscale computational approach employed in this work proves to be an efficient tool to shed new light on the complex dynamics of dense emulsions, from short-scale thin-film hydrodynamics, all the way up to global structure formation and statistics of the resulting droplets ensembles.
Purpose A recursive scheme for the ALIENOR method is proposed as a remedy for the difficulties induced by the method. A progressive focusing on the most promising region, in combination with a variation of the density of the alpha-dense curve, is proposed. Design/methodology/approach ALIENOR method is aimed at reducing the space dimensions of an optimization problem by spanning it by using a single alpha-dense curve: the curvilinear abscissa along the curve becomes the only design parameter for any design space. As a counterpart, the transformation of the objective function in the projected space is much more difficult to tackle. Findings A fine tuning of the procedure has been performed in order to identity the correct balance between the different elements of the procedure. The proposed approach has been tested by using a set of algebraic functions with up to 1,024 design variables, demonstrating the ability of the method in solving large scale optimization problem. Also an industrial application is presented. Originality/value In the knowledge of the author there is not a similar paper in the current literature.
ALIENOR optimization
Global optimization
Lipschitzian optimization
Reduced order base
Differential models, numerical methods and computer simulations play a fundamental rolein applied sciences. Since most of the differential models inspired by real world applications have noanalytical solutions, the development of numerical methods and efficient simulation algorithms playa key role in the computation of the solutions to many relevant problems. Moreover, since the modelparameters in mathematical models have interesting scientific interpretations and their values areoften unknown, estimation techniques need to be developed for parameter identification against themeasured data of observed phenomena. In this respect, this Special Issue collects some importantdevelopments in different areas of application.
Questo documento riassume l'attività svolta nei vari WP, le azioni completate e lo stato di del progetto per il
periodo di attività dal 16 giugno 2020 (RA2) al 9 giugno 2021 (RA3).
Given the definition of Software Unit (SU) as a computer program, which takes some input data and processesthem producing output data, this Technical Note (TN) provides some general guidelines to prepare the scientificand technical documentation of the different SUs developed and shared by the partners of the "FORUM Scienza"project.
The COVID-19 pandemic has impacted on every human activity and, because of theurgency of finding the proper responses to such an unprecedented emergency, itgenerated a diffused societal debate. The online version of this discussion was notexempted by the presence of misinformation campaigns, but, differently from whatalready witnessed in other debates, the COVID-19 -intentional or not- flow of falseinformation put at severe risk the public health, possibly reducing the efficacy ofgovernment countermeasures. In this manuscript, we study theeffectiveimpact ofmisinformation in the Italian societal debate on Twitter during the pandemic,focusing on the various discursive communities. In order to extract suchcommunities, we start by focusing on verified users, i.e., accounts whose identity isofficially certified by Twitter. We start by considering each couple of verified users andcount how many unverified ones interacted with both of them via tweets or retweets:if this number is statically significant, i.e. so great that it cannot be explained only bytheir activity on the online social network, we can consider the two verified accountsas similar and put a link connecting them in a monopartite network of verified users.The discursive communities can then be found by running a community detectionalgorithm on this network.We observe that, despite being a mostly scientific subject, the COVID-19 discussionshows a clear division in what results to be different political groups. We filter thenetwork of retweets from random noise and check the presence of messagesdisplaying URLs. By using the well known browser extension NewsGuard, we assessthe trustworthiness of the most recurrent news sites, among those tweeted by thepolitical groups. The impact of low reputable posts reaches the 22.1% in the right andcenter-right wing community and its contribution is even stronger in absolutenumbers, due to the activity of this group: 96% of all non reputable URLs shared bypolitical groups come from this community.
The problem of modeling water flow in the root zone with plant root absorption is of crucial importance in many environmental and agricultural issues, and is still of interest in the applied mathematics community. In this work we propose a formal justification and a theoretical background of a recently introduced numerical approach, based on the shooting method, for integrating the unsaturated flow equation with a sink term accounting for the root water uptake model. Moreover, we provide various numerical simulations for this method, comparing the results with the numerical solutions obtained by MATLAB pdepe.
Quantitative Methods for the Prioritization of Foods Implicated in the Transmission of Hepatititis E to Humans in Italy
Moro, Ornella
;
Suffredini, Elisabetta
;
Isopi, Marco
;
Tosti, Maria Elena
;
Schembri, Pietro
;
Scavia, Gaia
Hepatitis E is considered an emerging foodborne disease in Europe. Several types of foods are implicated in the transmission of the hepatitis E virus (HEV) to humans, in particular, pork and wild boar products. We developed a parametric stochastic model to estimate the risk of foodborne exposure to HEV in the Italian population and to rank the relevance of pork products with and without liver (PL and PNL, respectively), leafy vegetables, shellfish and raw milk in HEV transmission. Original data on HEV prevalence in different foods were obtained from a recent sampling study conducted in Italy at the retail level. Other data were obtained by publicly available sources and published literature. The model output indicated that the consumption of PNL was associated with the highest number of HEV infections in the population. However, the sensitivity analysis showed that slight variations in the consumption of PL led to an increase in the number of HEV infections much higher than PNL, suggesting that PL at an individual level are the top risky food. Uncertainty analysis underlined that further characterization of the pork products preparation and better assessment of consumption data at a regional level is critical information for fine-tuning the most risky implicated food items in Italy.
epidemiology
food safety
hepatitis E virus
mathematical modeling
Convective flows coupled with solidification or melting in water bodies play a major role in shaping geophysical landscapes. Particularly in relation to the global climate warming scenario, it is essential to be able to accurately quantify how water-body environments dynamically interplay with ice formation or melting process. Previous studies have revealed the complex nature of the icing process, but have often ignored one of the most remarkable particularities of water, its density anomaly, and the induced stratification layers interacting and coupling in a complex way in the presence of turbulence. By combining experiments, numerical simulations, and theoretical modeling, we investigate solidification of freshwater, properly considering phase transition, water density anomaly, and real physical properties of ice and water phases, which we show to be essential for correctly predicting the different qualitative and quantitative behaviors. We identify, with increasing thermal driving, four distinct flow-dynamics regimes, where different levels of coupling among ice front and stably and unstably stratified water layers occur. Despite the complex interaction between the ice front and fluid motions, remarkably, the average ice thickness and growth rate can be well captured with the theoretical model. It is revealed that the thermal driving has major effects on the temporal evolution of the global icing process, which can vary from a few days to a few hours in the current parameter regime. Our model can be applied to general situations where the icing dynamics occur under different thermal and geometrical conditions.
Rayleigh–Bénard convection
density anomaly
hydrodynamic turbulence
ice dynamics
solidification
Turbulent emulsions are complex physical systems characterized by a strong and dynamical coupling between small-scale droplets and large-scale rheology. By using a specifically designed Taylor-Couette shear flow system, we are able to characterize the statistical properties of a turbulent emulsion made of oil droplets dispersed in an ethanol-water continuous solution, at an oil volume fraction up to 40Â %. We find that the dependence of the droplet size on the Reynolds number of the flow at a volume fraction of 1Â % can be well described by the Hinze criterion. The distribution of droplet sizes is found to follow a log-normal distribution, hinting at a fragmentation process as the possible mechanism dominating droplet formation. Additionally, the effective viscosity of the turbulent emulsion increases with the volume fraction of the dispersed oil phase, and decreases when the shear strength is increased. We find that the dependence of the effective viscosity on the shear rate can be described by the Herschel-Bulkley model, with a flow index monotonically decreasing with increasing oil volume fraction. This finding indicates that the degree of shear thinning systematically increases with the volume fraction of the dispersed phase. The current findings have important implications for bridging the knowledge on turbulence and low-Reynolds-number emulsion flows to turbulent emulsion flows.
Soft glassy materials such as mayonnaise, wet clays, or dense microgels display a solid-to-liquid transition under external shear. Such a shear-induced transition is often associated with a nonmonotonic stress response in the form of a stress maximum referred to as “stress overshoot.” This ubiquitous phenomenon is characterized by the coordinates of the maximum in terms of stress and strain that both increase as weak power laws of the applied shear rate. Here we rationalize such power-law scalings using a continuum model that predicts two different regimes in the limit of low and high applied shear rates. The corresponding exponents are directly linked to the steady-state rheology and are both associated with the nucleation and growth dynamics of a fluidized region. Our work offers a consistent framework for predicting the transient response of soft glassy materials upon startup of shear from the local flow behavior to the global rheological observables.
Spin-glass dynamics in the presence of a magnetic field: Exploration of microscopic properties
Paga I.
;
Zhai Q.
;
Baity-Jesi M.
;
Calore E.
;
Cruz A.
;
Fernandez L. A.
;
Gil-Narvion J. M.
;
Gonzalez-Adalid Pemartin I.
;
Gordillo-Guerrero A.
;
Iiguez D.
;
Maiorano A.
;
Vincenzo Marinari
;
Martin-Mayor V.
;
Moreno-Gordo J.
;
Muoz-Sudupe A.
;
Navarro D.
;
Orbach R. L.
;
Parisi G.
;
Perez-Gaviro S.
;
Federico Ricci-Tersenghi
;
Ruiz-Lorenzo J. J.
;
Schifano S. F.
;
Schlagel D. L.
;
Seoane B.
;
Tarancon A.
;
Tripiccione R.
;
Yllanes D.
The synergy between experiment, theory, and simulations enables a microscopic analysis of spin-glass dynamics in a magnetic field in the vicinity of and below the spin-glass transition temperature T g. The spin-glass correlation length, ξ(t, t w; T), is analysed both in experiments and in simulations in terms of the waiting time t w after the spin glass has been cooled down to a stabilised measuring temperature T < T g and of the time t after the magnetic field is changed. This correlation length is extracted experimentally for a CuMn 6 at. % single crystal, as well as for simulations on the Janus II special-purpose supercomputer, the latter with time and length scales comparable to experiment. The non-linear magnetic susceptibility is reported from experiment and simulations, using ξ(t, t w; T) as the scaling variable. Previous experiments are reanalysed, and disagreements about the nature of the Zeeman energy are resolved. The growth of the spin-glass magnetisation in zero-field magnetisation experiments, M ZFC(t, t w; T), is measured from simulations, verifying the scaling relationships in the dynamical or non-equilibrium regime. Our preliminary search for the de Almeida-Thouless line in D = 3 is discussed.
Cooling and heating faster a system is a crucial problem in science, technology, and industry. Indeed, choosing the best thermal protocol to reach a desired temperature or energy is not a trivial task. Noticeably, we find that the phase transitions may speed up thermalization in systems where there are no conserved quantities. In particular, we show that the slow growth of magnetic domains shortens the overall time that the system takes to reach a final desired state. To prove that statement, we use intensive numerical simulations of a prototypical many-body system, namely, the two-dimensional Ising model.
Temperature chaos is present in off-equilibrium spin-glass dynamics
Baity-Jesi M.
;
Calore E.
;
Cruz A.
;
Fernandez L. A.
;
Gil-Narvion J. M.
;
Gonzalez-Adalid Pemartin I.
;
Gordillo-Guerrero A.
;
Iniguez D.
;
Maiorano A.
;
Vincenzo Marinari
;
Martin-Mayor V.
;
Moreno-Gordo J.
;
Munoz-Sudupe A.
;
Navarro D.
;
Paga I.
;
Parisi G.
;
Perez-Gaviro S.
;
Federico Ricci-Tersenghi
;
Ruiz-Lorenzo J. J.
;
Schifano S. F.
;
Seoane B.
;
Tarancon A.
;
Tripiccione R.
;
Yllanes D.
Experiments featuring non-equilibrium glassy dynamics under temperature changes still await interpretation. There is a widespread feeling that temperature chaos (an extreme sensitivity of the glass to temperature changes) should play a major role but, up to now, this phenomenon has been investigated solely under equilibrium conditions. In fact, the very existence of a chaotic effect in the non-equilibrium dynamics is yet to be established. In this article, we tackle this problem through a large simulation of the 3D Edwards-Anderson model, carried out on the Janus II supercomputer. We find a dynamic effect that closely parallels equilibrium temperature chaos. This dynamic temperature-chaos effect is spatially heterogeneous to a large degree and turns out to be controlled by the spin-glass coherence length ξ. Indeed, an emerging length-scale ξ* rules the crossover from weak (at ξ ≪ ξ*) to strong chaos (ξ ≫ ξ*). Extrapolations of ξ* to relevant experimental conditions are provided.
Next-generation battery research will heavily rely on physico-chemical models, combined with deep learning methods and high-throughput and quantitative analysis of experimental datasets, encoding spectral information in space and time. These tasks will require highly efficient computational approaches, to yield rapidly accurate approximations of the models. This paper explores the capabilities of a representative range of model reduction techniques to face this problem in the case of a well-assessed electrochemical phase-formation model. We consider the Proper Orthogonal Decomposition (POD) with a Galerkin projection and the Dynamic Mode Decomposition (DMD) techniques to deal first of all with a semi-linear heat equation 2D in space as a test problem. As an application, we show that it is possible to save computational time by applying POD-Galerkin for different choices of the parameters without recalculating the snapshot matrix. Finally, we consider two reaction–diffusion (RD) PDE systems with Turing-type dynamics: the well-known Schnackenberg model and the DIB model for electrochemical phase formation. We show that their reduced models obtained by POD and DMD with suitable low-dimensional projections are able to approximate carefully both the Turing patterns at the steady state and the reactivity dynamics in the transient regime. Finally, for the DIB model we show that POD-Galerkin applied for different choices of parameters, by calculating once the snapshot matrices, is able to find reduced Turing patterns of different morphology.
Battery modelling
Dynamic Mode Decomposition
Model Order Reduction (MOR)
POD-Galerkin
Reaction–diffusion PDE systems
Turing patterns
Cherenkov probes and runaway electrons diagnostics
Kwiatkowski R.
;
Rabinski M.
;
Sadowski M. J.
;
Zebrowski J.
;
Karpinski P.
;
Coda S.
;
Agostini M.
;
Albanese R.
;
Alberti S.
;
Alessi E.
;
Allan S.
;
Allcock J.
;
Ambrosino R.
;
Anand H.
;
Andrebe Y.
;
Arnichand H.
;
Auriemma F.
;
Ayllon-Guerola J. M.
;
Bagnato F.
;
Ball J.
;
Baquero-Ruiz M.
;
Beletskii A. A.
;
Bernert M.
;
Bin W.
;
Blanchard P.
;
Blanken T. C.
;
Boedo J. A.
;
Bogar O.
;
Bolzonella T.
;
Bombarda F.
;
Bonanomi N.
;
Bouquey F.
;
Bowman C.
;
Brida D.
;
Bucalossi J.
;
Buermans J.
;
Bufferand H.
;
Buratti P.
;
Calabro G.
;
Calacci L.
;
Camenen Y.
;
Carnevale D.
;
Carpanese F.
;
Carr M.
;
Carraro L.
;
Casolari A.
;
Causa F.
;
Cerovsky J.
;
Chellai O.
;
Chmielewski P.
;
Choi D.
;
Christen N.
;
Ciraolo G.
;
Cordaro L.
;
Costea S.
;
Cruz N.
;
Czarnecka A.
;
Molin A. D.
;
David P.
;
Decker J.
;
De Oliveira H.
;
Douai D.
;
Dreval M. B.
;
Dudson B.
;
Dunne M.
;
Duval B. P.
;
Eich T.
;
Elmore S.
;
Embreus O.
;
Esposito B.
;
Faitsch M.
;
Farnik M.
;
Fasoli A.
;
Fedorczak N.
;
Felici F.
;
Feng S.
;
Feng X.
;
Ferro G.
;
Fevrier O.
;
Ficker O.
;
Fil A.
;
Fontana M.
;
Frassinetti L.
;
Furno I.
;
Gahle D. S.
;
Galassi D.
;
Galazka K.
;
Gallo A.
;
Galperti C.
;
Garavaglia S.
;
Garcia J.
;
Garcia-Munoz M.
;
Garrido A. J.
;
Garrido I.
;
Gath J.
;
Geiger B.
;
Giruzzi G.
;
Gobbin M.
;
Goodman T. P.
;
Gorini G.
;
Gospodarczyk M.
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Granucci G.
;
Graves J. P.
;
Gruca M.
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Gyergyek T.
;
Hakola A.
;
Happel T.
;
Harrer G. F.
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Harrison J.
;
Havlickova E.
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Hawke J.
;
Henderson S.
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Hennequin P.
;
Hesslow L.
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Hogeweij D.
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Hogge J. -P.
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Hopf C.
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Hoppe M.
;
Horacek J.
;
Huang Z.
;
Hubbard A.
;
Iantchenko A.
;
Igochine V.
;
Innocente P.
;
Schrittwieser C. I.
;
Isliker H.
;
Jacquier R.
;
Jardin A.
;
Kappatou A.
;
Karpushov A.
;
Kazantzidis P. -V.
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Keeling D.
;
Kirneva N.
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Komm M.
;
Kong M.
;
Kovacic J.
;
Krawczyk N.
;
Kudlacek O.
;
Kurki-Suonio T.
;
Kwiatkowski R.
;
Labit B.
;
Lazzaro E.
;
Linehan B.
;
Lipschultz B.
;
Llobet X.
;
Lombroni R.
;
Loschiavo V. P.
;
Lunt T.
;
Macusova E.
;
Madsen J.
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Maljaars E.
;
Mantica P.
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Maraschek M.
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Marchetto C.
;
Marco A.
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Mariani A.
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Marini C.
;
Martin Y.
;
Matos F.
;
Maurizio R.
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Mavkov B.
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Mazon D.
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McCarthy P.
;
McDermott R.
;
Menkovski V.
;
Merle A.
;
Meyer H.
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Micheletti D.
;
Militello F.
;
Mitosinkova K.
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Mlynar J.
;
Moiseenko V.
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Cabrera P. A. M.
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Morales J.
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Moret J. -M.
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Moro A.
;
Mumgaard R. T.
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Naulin V.
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Nem R. D.
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Nespoli F.
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Nielsen A. H.
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Nielsen S. K.
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Nocente M.
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Nowak S.
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Offeddu N.
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Orsitto F. P.
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Paccagnella R.
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Palha A.
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Papp G.
;
Pau A.
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Pavlichenko R. O.
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Perek A.
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Pericoli Ridolfini V.
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Pesamosca F.
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Piergotti V.
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Pigatto L.
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Piovesan P.
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Piron C.
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Plyusnin V.
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Poli E.
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Porte L.
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Pucella G.
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Puiatti M. E.
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Putterich T.
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Rasmussen J. J.
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Ravensbergen T.
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Reich M.
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Reimerdes H.
;
Reimold F.
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Reux C.
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Ricci D.
;
Ricci P.
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Rispoli N.
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Rosato J.
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Saarelma S.
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Salewski M.
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Salmi A.
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Sauter O.
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Scheffer M.
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Schlatter C.
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Schneider B. S.
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Schrittwieser R.
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Sharapov S.
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Sheeba R. R.
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Sheikh U.
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Shousha R.
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Silva M.
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Sinha J.
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Sozzi C.
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Spolaore M.
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Stipani L.
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Strand P.
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Tala T.
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Biwole A. S. T.
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Teplukhina A. A.
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Testa D.
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Theiler C.
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Thornton A.
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Tomaz G.
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Tomes M.
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Tran M. Q.
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Tsironis C.
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Tsui C. K.
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Urban J.
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Valisa M.
;
Vallar M.
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Van Vugt D.
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Vartanian S.
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Vasilovici O.
;
Verhaegh K.
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Vermare L.
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Vianello N.
;
Viezzer E.
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Vijvers W. A. J.
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Villone F.
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Voitsekhovitch I.
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Vu N. M. T.
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Walkden N.
;
Wauters T.
;
Weiland M.
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Weisen H.
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Wensing M.
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Wiesenberger M.
;
Wilkie G.
;
Wischmeier M.
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Wu K.
;
Yoshida M.
;
Zagorski R.
;
Zanca P.
;
Zisis A.
;
Zuin M.
The beams of fast runaway electrons (RE), which are often produced during tokamak discharges, are particularly dangerous and can induce serious damages of the vacuum vessel and internal components of the machine. The proper and fast diagnostics of RE beams is essential for controlling the discharge, e.g., by early mitigation of disruptions and potentially dangerous RE beams. The diagnostics of RE beams is usually based on measurements of the radiation emitted either by these electrons, or as a result of their interactions with plasma and/or vessel walls. Such a radiation is usually recorded by the means of probes placed outside the vacuum vessel. The method developed by our team is based on the probe located inside the vacuum vessel. The probe can be used to detect highly localized RE bunches and to determine their spatial and temporal characteristics. During last few years, the NCBJ team have developed and used the RE diagnostics based on the Cherenkov effect observed in diamond radiators coupled with fast photomultipliers. During the investigated discharges, the probe was inserted into the vacuum vessel, and its head was placed at the plasma edge, where fast RE are expected. A correlation between signals recorded using our probes and other diagnostics, e.g., hard x-ray signals, was also studied. In this paper, we present recent results of the RE measurements by means of Cherenkov probes, which were performed in the COMPASS and TCV tokamaks.
