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The planform is a defining feature of mantle convection. It can be gleaned from the stratigraphic record by mapping the continent-scale distribution of hiatus and no hiatus surfaces serving as a proxy for high and low dynamic topography. We carry this out for all continents apart from Antarctica for eight geological series since the Upper Jurassic, showing that: (i) the planform as indicated by our maps contains wavelengths of the order of 1000 km, smaller than the convective scales implied by the geoid. (ii) The planform changes on timescales of geological series (10–20 Myrs), smaller than the mantle transit time. (iii) Flood basalt eruptions are frequently preceded by hiatus surfaces. (iv) Some hiatus surfaces are not linked to any known plume, potentially reflecting the lateral transport of material in the asthenosphere. Our results reveal the importance of mantle viscosity stratification in shaping the convective planform and the resulting dynamic topography. Geodynamic Earth models should aim to reproduce the global characteristics of our maps, as well as specific regional events identified in this work. Finally, we separate the effects of sea-level variation from regional changes in base level induced by dynamic topography by contrasting the stratigraphic evolution of different regions. [ABSTRACT FROM AUTHOR]

Previous geodetic and teleseismic observations of the 2021 Mw ${M}_{\mathrm{w}}$7.4 Maduo earthquake imply surprising but difficult‐to‐constrain complexity, including rupture across multiple fault segments and supershear rupture. Here, we present an integrated analysis of multi‐fault 3D dynamic rupture models, high‐resolution optical correlation analysis, and joint optical‐InSAR slip inversion. Our preferred model, validated by the teleseismic multi‐peak moment rate release, includes unilateral eastward double‐onset supershear speeds and cascading rupture dynamically triggering two adjacent fault branches. We propose that pronounced along‐strike variation in fracture energy, complex fault geometries, and multi‐scale variable prestress drives this event's complex rupture dynamics. We illustrate how supershear transition has signatures in modeled and observed off‐fault deformation. Our study opens new avenues to combine observations and models to better understand complex earthquake dynamics, including local and potentially repeating supershear episodes across immature faults or under heterogeneous stress and strength conditions, which are potentially not unusual. Plain Language Summary: The mechanism of cascading rupture and supershear propagation, when fault moves faster than in situ shear wave speed on multiple fault segments, remains unclear. On 22 May 2021, a magnitude 7.4 strike‐slip earthquake occurred in central‐east Tibet with episodic supershear suggested by geodetic and seismological inversions. Here, we build a physics‐based 3D fully dynamic model, informed by regional tectonics, geomorphology, and high‐resolution geodetic data, to better understand the earthquake's behavior and its implications for seismic hazards. The preferred rupture scenario reproduces key features, such as multi‐peak moment release, asymmetric supershear fronts, and dynamic triggering of secondary fault branches. Our model suggests that regional stress field, geometric complexity, and the along‐strike variation of frictional properties are crucial for earthquake dynamics and coseismic surface damage patterns. Our mechanically viable model offers insights into a comprehensive knowledge of rupture complexity and regional seismic hazard assessment. Key Points: We present new high‐resolution optical correlation displacement analysis, joint geodetic slip, and multi‐segment 3D dynamic rupture modelsA preferred model has multi‐peak moment rate release, unilateral double‐onset supershear rupture, and dynamic triggering of two faultsComplex fault geometry, prestress heterogeneity, and fracture energy variability drive supershear transition and off‐fault damage pattern [ABSTRACT FROM AUTHOR]

A correlation between epilepsy and cellular redox imbalance has been suggested, although the mechanism by which oxidative stress (OS) can be implicated in this disorder is not clear. In the present study several oxidative stress markers and enzymes involved in OS have been determined. In particular, we examined the levels of 4-hydroxy-2-nonenal protein adducts (HNE-PA), a by-product of lipid peroxidation, and the activation of NADPH oxidase 2 (NOX2), as cellular source of superoxide (O(2)(-)), in surgically resected epileptic tissue from drug-resistant patients (N=50). In addition, we investigated whether oxidative-mediated protein damage can affect aquaporin-4 (AQP4), a water channel implicated in brain excitability and epilepsy. Results showed high levels of HNE-PA in epileptic hippocampus, in both neurons and glial cells and cytoplasmic positivity for p47(phox) and p67(phox) suggesting NOX2 activation. Interestingly, in epileptic tissue immunohistochemical localization of AQP4 was identified not only in perivascular astrocytic endfeet, but also in neurons. Nevertheless, negativity for AQP4 was observed in neurons in degeneration. Of note, HNE-mediated post-translational modifications of AQP4 were increased in epileptic tissues and double immunofluorescence clearly demonstrated co-localization of AQP4 and HNE-PA in epileptic hippocampal structures. The idea is that sudden, disorderly, and excessive neuronal discharges activates NOX2 with O(2)(-) production, leading to lipid peroxidation. The resulting generation of HNE targets AQP4, affecting water and ion balance. Therefore, we suggest that seizure induces oxidative damage as well as neuronal loss, thereby promoting neuronal hyperexcitability, also affecting water and ion balance by AQP4 modulation, and thus generating a vicious cycle.