Articles de revues : « EEG coregistration »

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Del Felice, Alessandra, Tiziano Zanoni, Mirko Avesani, Emanuela Formaggio, Silvia Storti, Antonio Fiaschi, Giuseppe Moretto et Paolo Manganotti. « EEG-fMRI coregistration in non-ketotic hyperglycemic occipital seizures ». Epilepsy Research 85, n^o 2-3 (août 2009) : 321–24. http://dx.doi.org/10.1016/j.eplepsyres.2009.03.025.

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Bruña, Ricardo, Delshad Vaghari, Andrea Greve, Elisa Cooper, Marius O. Mada et Richard N. Henson. « Modified MRI Anonymization (De-Facing) for Improved MEG Coregistration ». Bioengineering 9, n^o 10 (21 octobre 2022) : 591. http://dx.doi.org/10.3390/bioengineering9100591.

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Localising the sources of MEG/EEG signals often requires a structural MRI to create a head model, while ensuring reproducible scientific results requires sharing data and code. However, sharing structural MRI data often requires the face go be hidden to help protect the identity of the individuals concerned. While automated de-facing methods exist, they tend to remove the whole face, which can impair methods for coregistering the MRI data with the EEG/MEG data. We show that a new, automated de-facing method that retains the nose maintains good MRI-MEG/EEG coregistration. Importantly, behavioural data show that this “face-trimming” method does not increase levels of identification relative to a standard de-facing approach and has less effect on the automated segmentation and surface extraction sometimes used to create head models for MEG/EEG localisation. We suggest that this trimming approach could be employed for future sharing of structural MRI data, at least for those to be used in forward modelling (source reconstruction) of EEG/MEG data.

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Miles, Kelly, Catherine McMahon, Isabelle Boisvert, Ronny Ibrahim, Peter de Lissa, Petra Graham et Björn Lyxell. « Objective Assessment of Listening Effort : Coregistration of Pupillometry and EEG ». Trends in Hearing 21 (28 juillet 2017) : 233121651770639. http://dx.doi.org/10.1177/2331216517706396.

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Bagattini, Chiara, Tuomas P. Mutanen, Claudia Fracassi, Rosa Manenti, Maria Cotelli, Risto J. Ilmoniemi, Carlo Miniussi et Marta Bortoletto. « Predicting Alzheimer's disease severity by means of TMS–EEG coregistration ». Neurobiology of Aging 80 (août 2019) : 38–45. http://dx.doi.org/10.1016/j.neurobiolaging.2019.04.008.

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Formaggio, Emanuela, Silvia Francesca Storti, Roberto Cerini, Antonio Fiaschi et Paolo Manganotti. « Brain oscillatory activity during motor imagery in EEG-fMRI coregistration ». Magnetic Resonance Imaging 28, n^o 10 (décembre 2010) : 1403–12. http://dx.doi.org/10.1016/j.mri.2010.06.030.

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Gerloff, Christian, Wolfgang Grodd, Eckart Altenmüller, Rupert Kolb, Thomas Naegele, Uwe Klose, Karsten Voigt et Johannes Dichgans. « Coregistration of EEG and fMRI in a simple motor task ». Human Brain Mapping 4, n^o 3 (1996) : 199–209. http://dx.doi.org/10.1002/(sici)1097-0193(1996)4:3<199 ::aid-hbm4>3.0.co;2-z.

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Wallois, F., M. Mahmoudzadeh, K. Kazemi, N. Roche, A. Aarabi, G. Kongolo, S. Goudjil et R. Grebe. « W16.1 Dynamics of the preterm brain through simultaneous EEG-NIRS coregistration ». Clinical Neurophysiology 122 (juin 2011) : S51. http://dx.doi.org/10.1016/s1388-2457(11)60170-3.

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Dimigen, Olaf, Werner Sommer, Annette Hohlfeld, Arthur M. Jacobs et Reinhold Kliegl. « Coregistration of eye movements and EEG in natural reading : Analyses and review. » Journal of Experimental Psychology : General 140, n^o 4 (2011) : 552–72. http://dx.doi.org/10.1037/a0023885.

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Formaggio, E., S. F. Storti, M. Avesani, R. Cerini, F. Milanese, A. Gasparini, M. Acler et al. « EEG and fMRI Coregistration To Investigate The Cortical Oscillatory Activities During Finger Movement ». NeuroImage 47 (juillet 2009) : S148. http://dx.doi.org/10.1016/s1053-8119(09)71514-9.

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Formaggio, Emanuela, Silvia Francesca Storti, Mirko Avesani, Roberto Cerini, Franco Milanese, Anna Gasparini, Michele Acler, Roberto Pozzi Mucelli, Antonio Fiaschi et Paolo Manganotti. « EEG and fMRI Coregistration to Investigate the Cortical Oscillatory Activities During Finger Movement ». Brain Topography 21, n^o 2 (22 juillet 2008) : 100–111. http://dx.doi.org/10.1007/s10548-008-0058-1.

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Ervin, Brian, Leonid Rozhkov, Jason Buroker, James L. Leach, Francesco T. Mangano, Hansel M. Greiner, Katherine D. Holland et Ravindra Arya. « Fast Automated Stereo-EEG Electrode Contact Identification and Labeling Ensemble ». Stereotactic and Functional Neurosurgery 99, n^o 5 (2021) : 393–404. http://dx.doi.org/10.1159/000515090.

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Introduction: Stereotactic electroencephalography (SEEG) has emerged as the preferred modality for intracranial monitoring in drug-resistant epilepsy (DRE) patients being evaluated for neurosurgery. After implantation of SEEG electrodes, it is important to determine the neuroanatomic locations of electrode contacts (ECs), to localize ictal onset and propagation, and integrate functional information to facilitate surgical decisions. Although there are tools for coregistration of preoperative MRI and postoperative CT scans, identification, sorting, and labeling of SEEG ECs is often performed manually, which is resource intensive. We report development and validation of a software named Fast Automated SEEG Electrode Contact Identification and Labeling Ensemble (FASCILE). Methods: FASCILE is written in Python 3.8.3 and employs a novel automated method for identifying ECs, assigning them to respected SEEG electrodes, and labeling. We compared FASCILE with our clinical process of identifying, sorting, and labeling ECs, by computing localization error in anteroposterior, superoinferior, and lateral dimensions. We also measured mean Euclidean distances between ECs identified by FASCILE and the clinical method. We compared time taken for EC identification, sorting, and labeling for the software developer using FASCILE, a first-time clinical user using FASCILE, and the conventional clinical process. Results: Validation in 35 consecutive DRE patients showed a mean overall localization error of 0.73 ± 0.15 mm. FASCILE required 10.7 ± 5.5 min/patient for identifying, sorting, and labeling ECs by a first-time clinical user, compared to 3.3 ± 0.7 h/patient required for the conventional clinical process. Conclusion: Given the accuracy, speed, and ease of use, we expect FASCILE to be used frequently for SEEG-driven epilepsy surgery. It is freely available for noncommercial use. FASCILE is specifically designed to expedite localization of ECs, assigning them to respective SEEG electrodes (sorting), and labeling them and not for coregistration of CT and MRI data as there are commercial software available for this purpose.

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Bortoletto, Marta, Domenica Veniero, Gregor Thut et Carlo Miniussi. « The contribution of TMS–EEG coregistration in the exploration of the human cortical connectome ». Neuroscience & ; Biobehavioral Reviews 49 (février 2015) : 114–24. http://dx.doi.org/10.1016/j.neubiorev.2014.12.014.

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de León, Sira Carrasco-García, Guiomar Niso, Leonidas Canuet, Laura Burriel-Lobo, Fernando Maestú et María Gudín Rodríguez-Magariños. « Praxis-induced seizures in a patient with juvenile myoclonic epilepsy : MEG-EEG coregistration study ». Epilepsy & ; Behavior Case Reports 5 (2016) : 1–5. http://dx.doi.org/10.1016/j.ebcr.2015.10.002.

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Brosnan, Méadhbh B., Mahnaz Arvaneh, Siobhán Harty, Tara Maguire, Redmond O'Connell, Ian H. Robertson et Paul M. Dockree. « Prefrontal Modulation of Visual Processing and Sustained Attention in Aging, a tDCS–EEG Coregistration Approach ». Journal of Cognitive Neuroscience 30, n^o 11 (novembre 2018) : 1630–45. http://dx.doi.org/10.1162/jocn_a_01307.

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The ability to sustain attention is integral to healthy cognition in aging. The right PFC (rPFC) is critical for maintaining high levels of attentional focus. Whether plasticity of this region can be harnessed to support sustained attention in older adults is unknown. We used transcranial direct current stimulation to increase cortical excitability of the rPFC, while monitoring behavioral and electrophysiological markers of sustained attention in older adults with suboptimal sustained attention capacity. During rPFC transcranial direct current stimulation, fewer lapses of attention occurred and electroencephalography signals of frontal engagement and early visual attention were enhanced. To further verify these results, we repeated the experiment in an independent cohort of cognitively typical older adults using a different sustained attention paradigm. Again, prefrontal stimulation was associated with fewer attentional lapses. These experiments suggest the rPFC can be manipulated in later years to increase top–down modulation over early sensory processing and improve sustained attention performance. This holds valuable information for the development of neurorehabilitation protocols to ameliorate age-related deficits in this capacity.

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Beltramello, G. « Coregistration of EEG and fMRI in rolandic epilepsy with evoked spikes by peripheral tapping stimulation ». Electroencephalography and Clinical Neurophysiology 103, n^o 1 (juillet 1997) : 83. http://dx.doi.org/10.1016/s0013-4694(97)88331-2.

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Zanon, Marco, Sara Borgomaneri et Alessio Avenanti. « Action-related dynamic changes in inferior frontal cortex effective connectivity : A TMS/EEG coregistration study ». Cortex 108 (novembre 2018) : 193–209. http://dx.doi.org/10.1016/j.cortex.2018.08.004.

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Storti, Silvia Francesca, Emanuela Formaggio, Alberto Beltramello, Antonio Fiaschi et Paolo Manganotti. « Wavelet Analysis as a Tool for Investigating Movement-Related Cortical Oscillations in EEG-fMRI Coregistration ». Brain Topography 23, n^o 1 (18 novembre 2009) : 46–57. http://dx.doi.org/10.1007/s10548-009-0117-2.

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Blount, Jeffrey P., Jason Cormier, Hyunmi Kim, Pongkiat Kankirawatana, Kristen O. Riley et Robert C. Knowlton. « Advances in intracranial monitoring ». Neurosurgical Focus 25, n^o 3 (septembre 2008) : E18. http://dx.doi.org/10.3171/foc/2008/25/9/e18.

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Intracranial monitoring using electroencephalography (IC-EEG) continues to play a critical role in the assessment of patients with medically intractable localization-related epilepsy. There has been minimal change in grid or electrode design in the last 15–20 years, and the surgical approaches for implantation are unchanged. Intracranial monitoring using EEG allows detailed definition of the region of ictal onset and defines the epileptogenic zone, particularly with regard to adjacent potentially eloquent tissue. Recent developments of IC-EEG include the coregistration of functional imaging data such as magnetoencephalography to the frameless navigation systems. Despite significant inherent limitations that are often overlooked, IC-EEG remains the gold standard for localization of the epileptogenic cortex. Intracranial electrodes take a variety of different forms and may be placed either in the subdural (subdural strips and grids, depth electrodes) or extradural spaces (sphenoidal, peg, and epidural electrodes). Each form has its own advantages and shortcomings but extensive subdural implantation of electrodes is most common and is most comprehensively discussed. The indications for intracranial electrodes are reviewed.

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Pieramico, Giulia, Roberto Guidotti, Aino E. Nieminen, Antea D’Andrea, Alessio Basti, Victor H. Souza, Jaakko O. Nieminen et al. « TMS-Induced Modulation of EEG Functional Connectivity Is Affected by the E-Field Orientation ». Brain Sciences 13, n^o 3 (28 février 2023) : 418. http://dx.doi.org/10.3390/brainsci13030418.

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Coregistration of transcranial magnetic stimulation (TMS) and electroencephalography (EEG) allows non-invasive probing of brain circuits: TMS induces brain activation due to the generation of a properly oriented focused electric field (E-field) using a coil placed on a selected position over the scalp, while EEG captures the effects of the stimulation on brain electrical activity. Moreover, the combination of these techniques allows the investigation of several brain properties, including brain functional connectivity. The choice of E-field parameters, such as intensity, orientation, and position, is crucial for eliciting cortex-specific effects. Here, we evaluated whether and how the spatial pattern, i.e., topography and strength of functional connectivity, is modulated by the stimulus orientation. We systematically altered the E-field orientation when stimulating the left pre-supplementary motor area and showed an increase of functional connectivity in areas associated with the primary motor cortex and an E-field orientation-specific modulation of functional connectivity intensity.

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Esposito, Romina, Marta Bortoletto et Carlo Miniussi. « Integrating TMS, EEG, and MRI as an Approach for Studying Brain Connectivity ». Neuroscientist 26, n^o 5-6 (9 mai 2020) : 471–86. http://dx.doi.org/10.1177/1073858420916452.

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The human brain is a complex network in which hundreds of brain regions are interconnected via thousands of axonal pathways. The capability of such a complex system emerges from specific interactions among smaller entities, a set of events that can be described by the activation of interconnections between brain areas. Studies that focus on brain connectivity have the aim of understanding and modeling brain function, taking into account the spatiotemporal dynamics of neural communication between brain regions. Much of the current knowledge regarding brain connectivity has been obtained from stand-alone neuroimaging methods. Nevertheless, the use of a multimodal approach seems to be a powerful way to investigate effective brain connectivity, overcoming the limitations of unimodal approaches. In this review, we will present the advantages of an integrative approach in which transcranial magnetic stimulation–electroencephalography coregistration is combined with magnetic resonance imaging methods to explore effective neural interactions. Moreover, we will describe possible implementations of the integrative approach in open- and closed-loop frameworks where real-time brain activity becomes a contributor to the study of cognitive brain networks.

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Kretzschmar, Franziska, Matthias Schlesewsky et Adrian Staub. « Dissociating word frequency and predictability effects in reading : Evidence from coregistration of eye movements and EEG. » Journal of Experimental Psychology : Learning, Memory, and Cognition 41, n^o 6 (2015) : 1648–62. http://dx.doi.org/10.1037/xlm0000128.

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Schwartz, Theodore H. « Cortical Dyplasia : Complete Resection Correlates with Outcome…But, Complete Resection of What ? » Epilepsy Currents 9, n^o 4 (juillet 2009) : 100–102. http://dx.doi.org/10.1111/j.1535-7511.2009.01306.x.

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Incomplete Resection of Focal Cortical Dysplasia Is the Main Predictor of Poor Postsurgical Outcome. Krsek P, Maton B, Jayakar P, Dean P, Korman B, Rey G, Dunoyer C, Pacheco-Jacome E, Morrison G, Ragheb J, Vinters HV, Resnick T, Duchowny M. Neurology 2009;72(3):217–223. BACKGROUND: Focal cortical dysplasia (FCD) is recognized as the major cause of focal intractable epilepsy in childhood. Various factors influencing postsurgical seizure outcome in pediatric patients with FCD have been reported. OBJECTIVE: To analyze different variables in relation to seizure outcome in order to identify prognostic factors for selection of pediatric patients with FCD for epilepsy surgery. METHODS: A cohort of 149 patients with histologically confirmed mild malformations of cortical development or FCD with at least 2 years of postoperative follow-up was retrospectively studied; 113 subjects had at least 5 years of postoperative follow-up. Twenty-eight clinical, EEG, MRI, neuropsychological, surgical, and histopathologic parameters were evaluated. RESULTS: The only significant predictor of surgical success was completeness of surgical resection, defined as complete removal of the structural MRI lesion (if present) and the cortical region exhibiting prominent ictal and interictal abnormalities on intracranial EEG. Unfavorable surgical outcomes are mostly caused by overlap of dysplastic and eloquent cortical regions. There were nonsignificant trends toward better outcomes in patients with normal intelligence, after hemispherectomy and with FCD type II. Other factors such as age at seizure onset, duration of epilepsy, seizure frequency, associated pathologies including hippocampal sclerosis, extent of EEG and MRI abnormalities, as well as extent and localization of resections did not influence outcome. Twenty-five percent of patients changed Engel's class of seizure outcome after the second postoperative year. CONCLUSIONS: The ability to define and fully excise the entire region of dysplastic cortex is the most powerful variable influencing outcome in pediatric patients with focal cortical dysplasia. FDG-PET/MRI Coregistration Improves Detection of Cortical Dysplasia in Patients with Epilepsy. Salamon N, Kung J, Shaw SJ, Koo J, Koh S, Wu JY, Lerner JT, Sankar R, Shields WD, Engel J Jr, Fried I, Miyata H, Yong WH, Vinters HV, Mathern GW. Neurology 2008;71(20):1594–1601. OBJECTIVE: Patients with cortical dysplasia (CD) are difficult to treat because the MRI abnormality may be undetectable. This study determined whether fluorodeoxyglucose (FDG)-PET/MRI coregistration enhanced the recognition of CD in epilepsy surgery patients. METHODS: Patients from 2004–2007 in whom FDG-PET/MRI coregistration was a component of the presurgical evaluation were compared with patients from 2000–2003 without this technique. For the 2004–2007 cohort, neuroimaging and clinical variables were compared between patients with mild Palmini type I and severe Palmini type II CD. RESULTS: Compared with the 2000–2003 cohort, from 2004–2007 more CD patients were detected, most had type I CD, and fewer cases required intracranial electrodes. From 2004–2007, 85% of type I CD cases had normal non–University of California, Los Angeles (UCLA) MRI scans. UCLA MRI identified CD in 78% of patients, and 37% of type I CD cases had normal UCLA scans. EEG and neuroimaging findings were concordant in 52% of type I CD patients, compared with 89% of type II CD patients. FDG-PET scans were positive in 71% of CD cases, and type I CD patients had less hypometabolism compared with type II CD patients. Postoperative seizure freedom occurred in 82% of patients, without differences between type I and type II CD cases. CONCLUSIONS: Incorporating fluorodeoxyglucose-PET/MRI coregistration into the multimodality presurgical evaluation enhanced the noninvasive identification and successful surgical treatment of patients with cortical dysplasia (CD), especially for the 33% of patients with nonconcordant findings and those with normal MRI scans from mild type I CD.

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Mirandola, Laura, Gaetano Cantalupo, Anna Elisabetta Vaudano, Pietro Avanzini, Andrea Ruggieri, Francesco Pisani, Giuseppe Cossu et al. « Centrotemporal spikes during NREM sleep : The promoting action of thalamus revealed by simultaneous EEG and fMRI coregistration ». Epilepsy & ; Behavior Case Reports 1 (2013) : 106–9. http://dx.doi.org/10.1016/j.ebcr.2013.06.005.

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Ferdowsi, Saideh, Saeid Sanei et Vahid Abolghasemi. « A Predictive Modeling Approach to Analyze Data in EEG–fMRI Experiments ». International Journal of Neural Systems 25, n^o 01 (6 janvier 2015) : 1440008. http://dx.doi.org/10.1142/s0129065714400085.

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In this paper, a novel technique based on blind source extraction (BSE) using linear prediction is proposed to extract rolandic beta rhythm from electroencephalogram (EEG) recorded in a simultaneous EEG–fMRI experiment. We call this method CLP–BSE standing for constrained-linear-prediction BSE. Extracting event-related oscillations is a crucial task due to nonphase-locked nature and inter-trial variability of this event. The main objective of this work is to extract rolandic beta rhythm to measure event-related synchronization (ERS) with acceptable signal-to-noise ratio (SNR). The extracted rhythm is utilized for constructing a regressor to analyze functional magnetic resonance imaging (fMRI). The proposed method is a semi-blind technique which uses a spatio-temporal constraint for beta rhythm extraction. This constraint is derived from recorded EEG signals based on the prior knowledge about the frequency and location of the source of interest. The main reason of employing linear prediction as an effective algorithm to extract the EEG rhythm is the ability of extracting sources which have specific temporal structure. Performance of the proposed method is evaluated using both synthetic and real EEG data. The obtained results show that the proposed technique is able to extract ERS effectively. The maximum percentage of ERS obtained by filtering is 152% while the obtained ERS by CLP–BSE is 214%. In another experiment, the extracted event-related oscillations in beta band are used to make the necessary regressor for fMRI analysis. The results of EEG–fMRI coregistration confirm that there are correlation between the extracted rolandic beta rhythm and simultaneously recorded fMRI. This conclude that, the results of EEG–fMRI combination support the reliability of CLP–BSE output.

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Manganotti, Paolo, Emanuela Formaggio, Silvia Francesca Storti, Daniele De Massari, Alessandro Zamboni, Alessandra Bertoldo, Antonio Fiaschi et Gianna Maria Toffolo. « Time-frequency analysis of short-lasting modulation of EEG induced by intracortical and transcallosal paired TMS over motor areas ». Journal of Neurophysiology 107, n^o 9 (1 mai 2012) : 2475–84. http://dx.doi.org/10.1152/jn.00543.2011.

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Dynamic changes in spontaneous electroencephalogram (EEG) rhythms can be seen to occur with a high rate of variability. An innovative method to study brain function is by triggering oscillatory brain activity with transcranial magnetic stimulation (TMS). EEG-TMS coregistration was performed on five healthy subjects during a 1-day experimental session that involved four steps: baseline acquisition, unconditioned single-pulse TMS, intracortical inhibition (ICI, 3 ms) paired-pulse TMS, and transcallosal stimulation over left and right primary motor cortex (M1). A time-frequency analysis based on the wavelet method was used to characterize rapid modifications of oscillatory EEG rhythms induced by TMS. Single, paired, and transcallosal TMS applied on the sensorimotor areas induced rapid desynchronization over the frontal and central-parietal electrodes mainly in the alpha and beta bands, followed by a rebound of synchronization, and rapid synchronization of delta and theta activity. Wavelet analysis after a perturbation approach is a novel way to investigate modulation of oscillatory brain activity. The main findings are consistent with the concept that the human motor system may be based on networklike oscillatory cortical activity and might be modulated by single, paired, and transcallosal magnetic pulses applied to M1, suggesting a phenomenon of fast brain activity resetting and triggering of slow activity.

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Ferreri, Florinda, David Ponzo, Taina Hukkanen, Esa Mervaala, Mervi Könönen, Patrizio Pasqualetti, Fabrizio Vecchio, Paolo Maria Rossini et Sara Määttä. « Human brain cortical correlates of short-latency afferent inhibition : a combined EEG–TMS study ». Journal of Neurophysiology 108, n^o 1 (1 juillet 2012) : 314–23. http://dx.doi.org/10.1152/jn.00796.2011.

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When linking in time electrical stimulation of the peripheral nerve with transcranial magnetic stimulation (TMS), the excitability of the motor cortex can be modulated to evoke clear inhibition, as reflected by the amplitude decrement in the motor-evoked potentials (MEPs). This specific property, designated short-latency afferent inhibition (SAI), occurs when the nerve–TMS interstimulus interval (ISI) is approximately 25 ms and is considered to be a corticothalamic phenomenon. The aim of the present study was to use the electroencephalographic (EEG) responses to navigated-TMS coregistration to better characterize the neuronal circuits underlying SAI. The present experimental set included magnetic resonance imaging (MRI)–navigated TMS and 60-channel TMS-compatible EEG devices. TMS-evoked EEG responses and MEPs were analyzed in eight healthy volunteers; ISIs between median nerve and cortical stimulation were determined relative to the latency of the individual N20 component of the somatosensory-evoked potential (SEP) obtained after stimulation of the median nerve. ISIs from the latency of the N20 plus 3 ms and N20 plus 10 ms were investigated. In all experimental conditions, TMS-evoked EEG responses were characterized by a sequence of negative deflections peaking at approximately 7, 44, and 100 ms alternating with positive peaks at approximately 30, 60, and 180 ms post-TMS. Moreover, ISI N20+3 ms modulated both EEG-evoked activity and MEPs. In particular, it inhibited MEP amplitudes, attenuated cortical P60 and N100 responses, and induced motor cortex beta rhythm selective decrement of phase locking. The findings of the present experiment suggest the cortical origin of SAI that could result from the cortico–cortical activation of GABAergic-mediated inhibition onto the corticospinal neurons modulated by cholinergic activation able to reducing intralaminar inhibition and promoting intracolumnar inhibition.

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Monti, F., M. Naccarato, A. Draisci, M. Ukmar, L. Weiss et G. Pizzolato. « P26.1 Importance of thalamic reticular nucleus in the generation of myoclonic movements in Creutzfeldt–Jakob disease patients : A simultaneous coregistration EEG/fMRI study ». Clinical Neurophysiology 117 (septembre 2006) : 113–14. http://dx.doi.org/10.1016/j.clinph.2006.06.454.

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Ferreri, Florinda, Fabrizio Vecchio, Andrea Guerra, Francesca Miraglia, David Ponzo, Luca Vollero, Giulio Iannello et al. « Age related differences in functional synchronization of EEG activity as evaluated by means of TMS-EEG coregistrations ». Neuroscience Letters 647 (avril 2017) : 141–46. http://dx.doi.org/10.1016/j.neulet.2017.03.021.

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Polewski, P., W. Yao et L. Fang. « VERTICAL ORIENTATION CORRECTION OF UAV IMAGE-BASED POINT CLOUDS USING STATISTICAL MODELING OF GABLE ROOF GEOMETRY ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W13 (4 juin 2019) : 519–23. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w13-519-2019.

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Abstract. Coregistration of point clouds obtained from various sensors is an important part of workflows for automatic building reconstruction from remote sensing data. Many approaches assume a common Z axis between the coordinate systems, and perform coregistration in 2D. While this assumption is usually valid for laser scanning (LS) data, for photogrammetric point clouds the Z axis is in general different from the world Z axis, and requires correction e.g. by manually measured ground control points (GCP). In this paper, we propose a fully automatic, GCP-free procedure for finding the world Z axis in rural areas, based on the relationships of planar surfaces in building gable roofs. Instead of performing direct gable line detection, we derive these lines as theoretical intersections between adjacent roof planes from 3D shape fitting. Each gable roof then casts a vote for both the Z axis direction and sign based on roof convexity constraints, and the votes are aggregated through a non-parametric kernel density estimator model. Experiments on two real world UAV image-based point clouds show that the Z axis recovered by our method leads to high-accuracy planimetric coregistration, with a median distance over 89 as well as 149 matched linear feature pairs (respectively for dataset 1 and 2) lying below 1&thinsp;cm. Our results indicate that a high-quality vertical orientation can be achieved without using any GNSS or IMU hardware, which enables the use of low-cost UAV platforms for suburban and rural mapping tasks.

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Almeida, Luís, Rafael Almar, Erwin Bergsma, Etienne Berthier, Paulo Baptista, Erwan Garel, Olusegun Dada et Bruna Alves. « Deriving High Spatial-Resolution Coastal Topography From Sub-meter Satellite Stereo Imagery ». Remote Sensing 11, n^o 5 (12 mars 2019) : 590. http://dx.doi.org/10.3390/rs11050590.

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High spatial resolution coastal Digital Elevation Models (DEMs) are crucial to assess coastal vulnerability and hazards such as beach erosion, sedimentation, or inundation due to storm surges and sea level rise. This paper explores the possibility to use high spatial-resolution Pleiades (pixel size = 0.7 m) stereoscopic satellite imagery to retrieve a DEM on sandy coastline. A 40-km coastal stretch in the Southwest of France was selected as a pilot-site to compare topographic measurements obtained from Pleiades satellite imagery, Real Time Kinematic GPS (RTK-GPS) and airborne Light Detection and Ranging System (LiDAR). The derived 2-m Pleiades DEM shows an overall good agreement with concurrent methods (RTK-GPS and LiDAR; correlation coefficient of 0.9), with a vertical Root Mean Squared Error (RMS error) that ranges from 0.35 to 0.48 m, after absolute coregistration to the LiDAR dataset. The largest errors (RMS error > 0.5 m) occurred in the steep dune faces, particularly at shadowed areas. This work shows that DEMs derived from sub-meter satellite imagery capture local morphological features (e.g., berm or dune shape) on a sandy beach, over a large spatial domain.

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Stegmayer, K., B. Stephan, V. Tim, F. Andrea, W. Roland, M. Rene, S. Werner et W. Sebastian. « Searching for meaning in meaningless gestures, pathologic activity in amygdala, hippocampus and temporal pole during planning of gestures in schizophrenia ». European Psychiatry 33, S1 (mars 2016) : S200—S201. http://dx.doi.org/10.1016/j.eurpsy.2016.01.473.

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IntroductionSchizophrenia is characterized by poor social interaction contributing to poor functional outcome. Particularly nonverbal communication is disturbed. Neural correlates of impaired gesturing are currently unclear. We thus tested functional correlates of gesturing in schizophrenia patients and healthy controls.MethodsWe tested 22 patients and 25 controls with an event-related fMRI (instructed delay) paradigm to dissociate brain activation during planning and execution of meaningful (e.g. use scissors) and meaningless novel gestures. Preprocessing included realignment, coregistration, normalization and spatial smoothing. We used a two stage mixed effects model for statistical analysis. Conditions were contrasted against a linguistic control within and between groups. We correlated psychopathological characteristics with beta estimates of brain areas with between group effects.ResultsDuring planning and execution of both gesture subtypes both groups activated brain areas of the ventral and dorsal stream. However patients’ activity was less prominent and more left lateralized. During planning patients showed additional activity in bilateral temporal poles, amygdala and hippocampus associated with the level of delusions. Furthermore patients had increased dorsomedial prefrontal cortex and precuneus activity when planning meaningless gestures.ConclusionDuring the planning of meaningless gestures we detected aberrant activation of limbic structures in patients typically implicated in delusion formation, which also correlated with current severity of delusions. Moreover, planning of meaningless gestures relied on areas relevant for strategic control and attention. These results argue for a pathologic search for meaning in neutral gestures and increased control effort during planning of meaningless gestures in schizophrenia.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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Cucchiaro, Sara, Daniel J. Fallu, He Zhang, Kevin Walsh, Kristof Van Oost, Antony G. Brown et Paolo Tarolli. « Multiplatform-SfM and TLS Data Fusion for Monitoring Agricultural Terraces in Complex Topographic and Landcover Conditions ». Remote Sensing 12, n^o 12 (17 juin 2020) : 1946. http://dx.doi.org/10.3390/rs12121946.

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Agricultural terraced landscapes, which are important historical heritage sites (e.g., UNESCO or Globally Important Agricultural Heritage Systems (GIAHS) sites) are under threat from increased soil degradation due to climate change and land abandonment. Remote sensing can assist in the assessment and monitoring of such cultural ecosystem services. However, due to the limitations imposed by rugged topography and the occurrence of vegetation, the application of a single high-resolution topography (HRT) technique is challenging in these particular agricultural environments. Therefore, data fusion of HRT techniques (terrestrial laser scanning (TLS) and aerial/terrestrial structure from motion (SfM)) was tested for the first time in this context (terraces), to the best of our knowledge, to overcome specific detection problems such as the complex topographic and landcover conditions of the terrace systems. SfM–TLS data fusion methodology was trialed in order to produce very high-resolution digital terrain models (DTMs) of two agricultural terrace areas, both characterized by the presence of vegetation that covers parts of the subvertical surfaces, complex morphology, and inaccessible areas. In the unreachable areas, it was necessary to find effective solutions to carry out HRT surveys; therefore, we tested the direct georeferencing (DG) method, exploiting onboard multifrequency GNSS receivers for unmanned aerial vehicles (UAVs) and postprocessing kinematic (PPK) data. The results showed that the fusion of data based on different methods and acquisition platforms is required to obtain accurate DTMs that reflect the real surface roughness of terrace systems without gaps in data. Moreover, in inaccessible or hazardous terrains, a combination of direct and indirect georeferencing was a useful solution to reduce the substantial inconvenience and cost of ground control point (GCP) placement. We show that in order to obtain a precise data fusion in these complex conditions, it is essential to utilize a complete and specific workflow. This workflow must incorporate all data merging issues and landcover condition problems, encompassing the survey planning step, the coregistration process, and the error analysis of the outputs. The high-resolution DTMs realized can provide a starting point for land degradation process assessment of these agriculture environments and supplies useful information to stakeholders for better management and protection of such important heritage landscapes.

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Sidiropoulos, Panagiotis, et Jan-Peter Muller. « BATCH CO-REGISTRATION OF MARS HIGH-RESOLUTION IMAGES TO HRSC MC11-E MOSAIC ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (14 juin 2016) : 491–95. http://dx.doi.org/10.5194/isprs-archives-xli-b4-491-2016.

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Four NASA missions over the last forty years with onboard instruments for high-resolution orbital imaging have achieved both global coverage (with 6m CTX, 20m THEMIS-VIS and >8m Viking Orbiter cameras) as well as imaging with very high resolution in specific regions of interest (e.g. 25cm HiRISE and ≈1.5-12m MOC-NA cameras). Overall, this set of cameras have acquired more than 400,000 high-quality images of Mars with resolution between 25cm/pixel and 100m/pixel (Sidiropoulos and Muller, 2015). On the other hand, ESA has sent the only high-resolution stereo photogrammetric camera around Mars, HRSC onboard the Mars Express spacecraft, which has been mapping the Martian surface since 2004 with a resolution of 12.5 m/pixel (Jaumann et al., 2015). Initially the raw images are combined through an elaborate photogrammetric process to get (single-strip) 3D products (i.e. digital terrain models (DTMs) and derived orthorectified images (ORIs)). However, recently the processing chain has changed, and the single-strip product release was temporarily halted to be replaced by the production and release of mosaics of Mars quadrangles. The first product of this kind is the mosaic for the East part of quadrangle MC11 (i.e. the MC11-E mosaic), a product with 12.5 metres per pixel resolution in the panchromatic image and 50 metres per pixel resolution in the corresponding DTM (Gwinner et al., 2015). Such a product provides an excellent basemap to co-register and orthorectify all NASA high-resolution (≤100m/pixel) orbital images. The need for this co-registration to HRSC comes from their poor areo-referencing, which often leads to large deviations (reaching up to several kilometres) between the area they are supposed to image and the area they are actually imaging. After co-registration, all products are projected onto an common 3D coordinate system, which allows an examination of dynamic features of Mars through the changes that happen on its surface. In this work, we present the results of the batch coregistration of all NASA high-resolution orbiter images of MC11-E, i.e. almost 8,000 images in total. This task was conducted with an in-house pipeline which was modified in order to handle the different parameters of the mosaic in comparison to single-strip HRSC products and to process the large input data volumes within a realistic time. An outline of the processing pipeline is given, along with examples of co-registered images and statistics of the co-registration performance. We demonstrate how such a time series representation of the surface will open up new areas for exploration and understanding of the Martian surface.

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Sidiropoulos, Panagiotis, et Jan-Peter Muller. « BATCH CO-REGISTRATION OF MARS HIGH-RESOLUTION IMAGES TO HRSC MC11-E MOSAIC ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (14 juin 2016) : 491–95. http://dx.doi.org/10.5194/isprsarchives-xli-b4-491-2016.

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Four NASA missions over the last forty years with onboard instruments for high-resolution orbital imaging have achieved both global coverage (with 6m CTX, 20m THEMIS-VIS and >8m Viking Orbiter cameras) as well as imaging with very high resolution in specific regions of interest (e.g. 25cm HiRISE and ≈1.5-12m MOC-NA cameras). Overall, this set of cameras have acquired more than 400,000 high-quality images of Mars with resolution between 25cm/pixel and 100m/pixel (Sidiropoulos and Muller, 2015). On the other hand, ESA has sent the only high-resolution stereo photogrammetric camera around Mars, HRSC onboard the Mars Express spacecraft, which has been mapping the Martian surface since 2004 with a resolution of 12.5 m/pixel (Jaumann et al., 2015). Initially the raw images are combined through an elaborate photogrammetric process to get (single-strip) 3D products (i.e. digital terrain models (DTMs) and derived orthorectified images (ORIs)). However, recently the processing chain has changed, and the single-strip product release was temporarily halted to be replaced by the production and release of mosaics of Mars quadrangles. The first product of this kind is the mosaic for the East part of quadrangle MC11 (i.e. the MC11-E mosaic), a product with 12.5 metres per pixel resolution in the panchromatic image and 50 metres per pixel resolution in the corresponding DTM (Gwinner et al., 2015). Such a product provides an excellent basemap to co-register and orthorectify all NASA high-resolution (≤100m/pixel) orbital images. The need for this co-registration to HRSC comes from their poor areo-referencing, which often leads to large deviations (reaching up to several kilometres) between the area they are supposed to image and the area they are actually imaging. After co-registration, all products are projected onto an common 3D coordinate system, which allows an examination of dynamic features of Mars through the changes that happen on its surface. In this work, we present the results of the batch coregistration of all NASA high-resolution orbiter images of MC11-E, i.e. almost 8,000 images in total. This task was conducted with an in-house pipeline which was modified in order to handle the different parameters of the mosaic in comparison to single-strip HRSC products and to process the large input data volumes within a realistic time. An outline of the processing pipeline is given, along with examples of co-registered images and statistics of the co-registration performance. We demonstrate how such a time series representation of the surface will open up new areas for exploration and understanding of the Martian surface.

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Marta, Bortoletto, Veniero Domenica, Thut Gregor et Miniussi Carlo. « The Contribution of TMS-EEG Coregistration in the Exploration of the Human Connectome ». Frontiers in Human Neuroscience 9 (2015). http://dx.doi.org/10.3389/conf.fnhum.2015.217.00002.

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Guo, Zhihao, Chao Zhang, Xiu Wang, Chang Liu, Baotian Zhao, Jiajie Mo, Zhong Zheng et al. « Is intracranial electroencephalography mandatory for MRI-negative neocortical epilepsy surgery ? » Journal of Neurosurgery, 1 octobre 2022, 1–11. http://dx.doi.org/10.3171/2022.8.jns22995.

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OBJECTIVE MRI-negative focal epilepsy is one of the most challenging cases in surgical epilepsy treatment. Many epilepsy centers recommend intracranial electroencephalography (EEG) for MRI-negative cases, especially neocortical epilepsy. This retrospective study aimed to explore whether intracranial monitoring is mandatory in MRI-negative neocortical epilepsy surgery and the factors that significantly influence the decision on whether to perform intracranial recording. METHODS In this study, consecutive surgical patients with focal MRI-negative neocortical epilepsy were recruited. All patients underwent routine preoperative evaluation according to the dedicated protocol of the authors’ epilepsy center to determine the treatment strategy. Patients were divided into two groups according to the surgical strategy, i.e., a direct group and a stereo-EEG (SEEG)–guided group. History of epilepsy, seizure frequency, interictal and ictal EEG data, PET data, PET/MRI coregistration data, neuropathological findings, and surgical outcomes were compared between the two groups. Multivariate analysis was performed to identify factors influencing the decision to perform SEEG monitoring. RESULTS Sixty-four patients were included in this study, 19 and 45 of whom underwent direct and SEEG-guided cortical resection, respectively. At an average follow-up of 3.9 years postoperatively, 56 patients (87.5%) had Engel class I results without permanent neurological deficits. Surgical outcomes were not significantly different between the direct and SEEG-guided groups (94.7% vs 84.4%). PET hypometabolic abnormalities were detected in all patients. There were significant differences between the two groups in the extent of hypometabolism (focal vs nonfocal, p < 0.01) and pathological subtype (focal cortical dysplasia type II vs others, p = 0.03). Multivariate analysis revealed that the extent of hypometabolism (OR 0.01, 95% CI 0.00–0.15; p = 0.001) was the only independent factor affecting the treatment strategy. CONCLUSIONS Careful selection of patients with MRI-negative neocortical epilepsy may yield favorable outcomes after direct cortical resection without intracranial monitoring. PET/MRI coregistration plays an essential role in the preoperative evaluation and subsequent resection of these patients. Intracranial monitoring is not a mandatory requirement for surgery if the focal hypometabolic areas are consistent with the findings of semiology and scalp EEG.

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Milligan, Sara, Martín Antúnez, Horacio A. Barber et Elizabeth R. Schotter. « Are eye movements and EEG on the same page ? : A coregistration study on parafoveal preview and lexical frequency. » Journal of Experimental Psychology : General, 15 septembre 2022. http://dx.doi.org/10.1037/xge0001278.

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van der Cruijsen, Joris, Maria Carla Piastra, Ruud W. Selles et Thom F. Oostendorp. « A Method to Experimentally Estimate the Conductivity of Chronic Stroke Lesions : A Tool to Individualize Transcranial Electric Stimulation ». Frontiers in Human Neuroscience 15 (12 octobre 2021). http://dx.doi.org/10.3389/fnhum.2021.738200.

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The inconsistent response to transcranial electric stimulation in the stroke population is attributed to, among other factors, unknown effects of stroke lesion conductivity on stimulation strength at the targeted brain areas. Volume conduction models are promising tools to determine optimal stimulation settings. However, stroke lesion conductivity is often not considered in these models as a source of inter-subject variability. The goal of this study is to propose a method that combines MRI, EEG, and transcranial stimulation to estimate the conductivity of cortical stroke lesions experimentally. In this simulation study, lesion conductivity was estimated from scalp potentials during transcranial electric stimulation in 12 chronic stroke patients. To do so, first, we determined the stimulation configuration where scalp potentials are maximally affected by the lesion. Then, we calculated scalp potentials in a model with a fixed lesion conductivity and a model with a randomly assigned conductivity. To estimate the lesion conductivity, we minimized the error between the two models by varying the conductivity in the second model. Finally, to reflect realistic experimental conditions, we test the effect rotation of measurement electrode orientation and the effect of the number of electrodes used. We found that the algorithm converged to the correct lesion conductivity value when noise on the electrode positions was absent for all lesions. Conductivity estimation error was below 5% with realistic electrode coregistration errors of 0.1° for lesions larger than 50 ml. Higher lesion conductivities and lesion volumes were associated with smaller estimation errors. In conclusion, this method can experimentally estimate stroke lesion conductivity, improving the accuracy of volume conductor models of stroke patients and potentially leading to more effective transcranial electric stimulation configurations for this population.

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Meister, Gerhard, Joseph J. Knuble, Leland H. Chemerys, Hyeungu Choi, Nicholas R. Collins, Robert E. Eplee, Ulrik Gliese et al. « Test Results From the Prelaunch Characterization Campaign of the Engineering Test Unit of the Ocean Color Instrument of NASA’s Plankton, Aerosol, Cloud and Ocean Ecosystem (PACE) Mission ». Frontiers in Remote Sensing 3 (23 juin 2022). http://dx.doi.org/10.3389/frsen.2022.875863.

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This paper summarizes the results from the system level test campaign of the Engineering Test Unit (ETU) of the ‘Ocean Color Instrument’ (OCI), the primary payload of NASA’s ‘Plankton, Aerosol, Cloud and ocean Ecosystem’ (PACE) mission. The main goals of the test campaign were to optimize characterization procedures and evaluate system level performance relative to model predictions. Critical performance parameters such as radiometric gain, signal-to-noise ratio, polarization, instantaneous field-of-view, temperature sensitivity, relative spectral response and stability were evaluated for wavelengths from 600 to 2,260 nm and are in line with expectations. We expect the OCI flight unit to meet the PACE mission performance requirements. Building and testing the ETU has been extremely important for the development of the OCI flight unit (e.g. improved SNR by increasing the aperture, optimized thermal design), and we strongly recommend the inclusion of an ETU in the development of future spaceborne sensors that rely on novel technological designs. ETU testing led to the discovery of a hysteresis issue with the SWIR bands, and a correction algorithm was developed. Also, the coregistration of the SWIR bands relative to each other is worse than expected, but this was discovered too late in the schedule to remediate.

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