A palladium doped 1T-phase molybdenum disulfide-black phosphorene two-dimensional van der Waals heterostructure for visible-light enhanced electrocatalytic hydrogen evolution.

The electrocatalytic hydrogen evolution reaction (HER) is a green chemistry route for sustainable energy production. Compared to 2H-phase molybdenum disulfide (MoS2), the 1T-phase MoS2 (1T-MoS2) has higher theoretical activity and faster charge transfer kinetics, but the HER performance of 1T-MoS2 is commonly hindered by limited active edge/defect as well as poor structural stability. Herein, we synthesize a well-defined 2D vdW heterostructure composed of Pd doped 1T-MoS2 and black phosphorus (BP) nanosheets via electrostatic self-assembly. The spontaneous Pd doping under mild reaction conditions could introduce catalytically active sulfur vacancies in MoS2 without triggering a wide range of 1T to 2H phase transformation. The hetero-interfacial charge transfer from BP to Pd-1T-MoS2 can effectively improve the intrinsic activity of Pd-1T-MoS2 with a relatively low S vacancy concentration and simultaneously stabilize the 1T-phase structure. Due to the wide-range light absorption of BP nanosheets and the high carrier mobilities of 2D materials, the HER activity of the obtained Pd-1T-MoS2/BP could be further enhanced under ≥420 nm visible light illumination.

Semiologic subgroups of insulo-opercular seizures based on connectional architecture atlas.

OBJECTIVE: Insulo-opercular seizures are characterized by diverse semiology, related to the insula's multiple functional roles and extensive connectivity. We aimed to identify semiologic subgroups and correlate these with insulo-opercular subregions based on connectional architecture. METHODS: We retrospectively collected a large series of 37 patients with insulo-opercular seizures explored by stereoelectroencephalography (SEEG) from three epilepsy centers. A new human brain atlas (Brainnetome Atlas, BNA) based on both anatomic and functional connections was employed to segment insulo-opercular cortex. Semiology and SEEG changes were carefully reviewed and quantified. Principal component analysis and cluster analysis were used to correlate semiologic characteristics with insulo-opercular subregions. RESULTS: Four main semiologic subgroups were identified, organized along an anteroventral to posterodorsal axis based on BNA. Group 1 was characterized by epigastric sensation and/or integrated gestural motor behaviors with or without feelings of fear or rage, involving the anteroventral insular regions and mesial temporal lobes. Group 2 was characterized by auditory sensations and symmetric proximal/axial tonic signs involving the posteroventral temporal operculum. The characteristics of group 3 were orofacial and laryngeal signs, involving the intermediate insulo-opercular regions. The features of group 4 were somatosensory signs followed by nonintegrated gestural motor behaviors and/or asymmetric tonic signs involving the posterodorsal insulo-opercular regions with propagation to the mesial frontal lobes. Thus anteroventral seizure organizations predominantly showed limbic system semiology, whereas more posterodorsal regions were associated with semiology involving mainly the sensorimotor system. Subjective symptoms proved to be particularly discriminating factors. SIGNIFICANCE: Insulo-opercular seizures can be categorized in terms of clinical semiology and correlate with connectional architecture subregions along an anteroventral-posterodorsal axis in line with the cytoarchitectonic gradient rather than the gyral anatomy of the insula cortex. This provides new insights into facilitating differential diagnosis and presurgical localization but also highlights the importance of considering connectional architecture in determining neural correlates of complex semiologic patterns.

Distinctive epileptogenic networks for parietal operculum seizures.

OBJECTIVE: The present study investigated the electroclinical features and epileptogenic networks of parietal operculum seizures (POS) by using stereoelectroencephalography (SEEG) intracerebral recordings. METHODS: Comprehensive presurgical evaluation data of seven patients with drug-resistant epilepsy with POS were analyzed retrospectively. Stereoelectroencephalography-recorded seizures were processed visually and quantitatively by using epileptogenicity mapping (EM), which has been proposed to ergonomically quantify the epileptogenicity of brain structures with a neuroimaging approach. RESULTS: Six patients reported initial somatosensory or viscerosensitive symptoms. Ictal clinical signs comprised frequently nocturnal hypermotor seizures and contralateral focal motor seizures, including tonic, tonic-clonic, or dystonic seizures of the face and limbs. Interictal and ictal scalp EEG provided information regarding lateralization in the majority of patients, but the discharges were widely distributed over perisylvian or "rolandic-like" regions and the vertex. Furthermore, two subgroups of epileptogenic network organization were identified within POS by SEEG, visually and quantitatively, using an EM approach: group 1 (mesial frontal/cingulate networks) was observed in three patients who mainly exhibited hypermotor seizures; group 2 (perisylvian networks) was observed in four patients who mainly exhibited contralateral focal motor seizures. CONCLUSION: This study indicated that POS could be characterized by initial specific somatosensory sensations, followed by either frequently nocturnal hypermotor seizures or contralateral focal motor seizures. The distinctive seizure semiology depended on the organization of two primary epileptogenic networks. This article is part of the Special Issue "Individualized Epilepsy Management: Medicines, Surgery and Beyond.