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Recently, three-terminal synaptic devices have attracted considerable attention owing to their nondestructive weight-update behavior, which is attributed to the completely separated terminals for reading and writing. However, the structural limitations of these devices, such as a low array density and complex line design, are predicted to result in low processing speeds and high energy consumption of the entire system. Here, we propose a vertical three-terminal synapse featuring a remote weight update via ion gel, which is also extendable to a crossbar array structure. This synaptic device exhibits excellent synaptic characteristics, which are achieved via precise control of ion penetration onto the vertical channel through the weight-control terminal. Especially, the applicability of the developed vertical organic synapse array to neuromorphic computing is demonstrated using a simple crossbar synapse array. The proposed synaptic device technology is expected to be an important steppingstone to the development of high-performance and high-density neural networks. Though three-terminal organic synapses are attractive for artificial neural networks due their weight controllable property, their structural limitations hinder performance. Here, the authors report a crossbar synapse array featuring vertical organic synapses with remote weight update capability.

This study uses multiple ground and satellite‐based measurements to investigate the extreme ionospheric response to the Mother's Day storm on May 10–11, 2024. Prompt penetration electric field caused a significant enhancement in the ionospheric vertical drift (∼${\\sim} $95 m/s) and the equatorial electrojet strength (∼${\\sim} $  275 nT) over Jicamarca. These extreme eastward electric field perturbations, along with the large meridional wind, significantly altered the F‐region plasma fountain at different local times. The afternoon equatorial ionization anomaly (EIA) not only sustained for an exceptionally long duration (∼${\\sim} $12 hr) but also expanded spatially over time. The separation between the two peaks of EIA crests exceeded ∼48°${\\sim} 48{}^{\\circ}$and ∼70°${\\sim} 70{}^{\\circ}$in the morning and evening sectors, respectively. This study shows, for the first time, that unusually strong EIA can not only develop at different local times but can also sustain for long duration under favorable conditions, which has implications for space weather applications. Plain Language Summary The Earth's upper atmosphere is significantly influenced by space weather events, particularly geomagnetic storms. In this study, we investigate the impact of an intense geomagnetic storm that occurred on 10–11 May 2024 (popularly known as Mother's Day storm) on the equatorial and low‐latitude ionosphere. Using datasets from various ground and satellites‐based (SWARM, and GOLD satellites, Global GNSS receivers, Incoherent Scatter Radar (ISR), Fabry‐ Perot interferometers (FPI), and magnetometer) measurements, we show the impact of extreme prompt penetration of electric field on the development of plasma fountain during the storm. We observe a significant increase in electron density and TEC during the main phase of the storm. Our findings highlight the role of extreme space weather disturbances on the generation of EIA at different local times and the impact of the plasma distribution on the globe. We also observe different types of electric field perturbations on low latitude ionosphere during this severe geomagnetic storm. Key Points The plasma fountain during the Mother's Day storm was unusually strong across different local time sectors The combined effects of a strong penetration electric field and meridional wind sustained the plasma fountains for an extended period The EIA crest over the Jicamarca sector merged with the expanded auroral region

From microbes to large predators, there is increasing evidence that marine life is shaped by short-lived submesoscales currents that are difficult to observe, model, and explain theoretically. Whether and how these intense three-dimensional currents structure the productivity and diversity of marine ecosystems is a subject of active debate. Our synthesis of observations and models suggests that the shallow penetration of submesoscale vertical currents might limit their impact on productivity, though ecological interactions at the submesoscale may be important in structuring oceanic biodiversity. Short-lived three-dimensional submesoscale currents, responsible for swirling ocean color chlorophyll filaments, have long been thought to affect productivity. Current research suggests they may not be effective in enhancing phytoplankton growth, but may have important contributions to biodiversity.

The ideal root end filling material should form a tight seal in the root canal by adhering to the cavity walls. Several materials have been used for root end filling. The present study aims to find out and compare the bioactivity of Neo MTA Plus, Pro Root MTA White, BIODENTINE & glass ionomer cement as root end filling materials using 1% methylene blue as tracer. Materials and methods: 80 extracted human permanent maxillary anterior teeth were used in the study. They were divided into four groups. Specimens were sectioned transversely in the cervical area to separate the crown from the root. The root canal was obturated with gutta percha and zinc oxide eugenol sealers. Thereafter, each sample was resected apically by removing 3 mm of the apex and filled with different materials. Samples were kept in buffering solution at 37 °C until the recommended evaluation periods. The specimens were then suspended in 1% methylene blue for 24 h, prior to the analysis. The teeth were then sectioned, and dye penetration was examined, photographed, and evaluated under a stereomicroscope. Results: Vertical dye penetration showed significant differences across different groups. The minimum dye penetration was seen in Neo MTA plus followed by BIODENTINE, Pro Root MTA and maximum in GIC. There was no significant difference in dye penetration between Neo MTA plus and BIODENTINE both at fifteen days and one-month intervals. Conclusion: The present study suggests Neo MTA plus and BIODENTINE should be the preferred material for root end filling.

Commonly encountered problems, such as insufficient bearing capacity of the foundation and significant soil deformation, typically necessitate improvements to sandy soil. The excessive use of traditional soil improvement materials, such as cement and lime, causes irreversible damage to the ecological environment. As a sustainable soil reinforcement material, xanthan gum has broad application prospects with respect to its effects on the bearing capacity and deformation of sandy soil foundations. In this study, scanning electron microscope tests and cone penetration model tests based on particle image velocimetry technology were conducted to investigate the microstructure, mechanical behavior, and deformation characteristics around cones in sand treated with different xanthan gum rates. The test results show that the xanthan gum exerts cementation and filling effects between sand particles, enhanced the bearing capacity of sand. The displacement field around the cones in xanthan gum–treated sand during the penetration exhibits good symmetry. With increasing xanthan gum rate, the maximum displacement value and vertical influence range around the cone of xanthan gum-treated sand decrease, while the horizontal influence range increases. On the basis of the cone penetration test result, a predictive model for the vertical bearing capacity incorporating the xanthan gum rate is proposed using the Laboratoire Central des Ponts et Chaussées (LCPC) model. The research results can provide a scientific basis for using xanthan gum when designing and constructing sandy soil foundations.

In the process of directional well drilling, how to accurately model the real-time well trajectory is of great significance to improving the reservoir encounter rate and recovery rate. This paper provides a method to improve the accuracy of well trajectory by cleaning and correcting the continuous measurement data in combination with fixed measurement data, and then using the continuous measurement data for trajectory modeling. The continuous measurement data comes from the CG-STEER rotary steerable system. The well trajectory calculated by the continuous measurement data corrected by the above method greatly reduces the vertical depth calculation error during the drilling process, and effectively reduces the vertical depth error accumulation caused by the large spacing between fixed measurement points. It can effectively improve the drilling target accuracy and horizontal section penetration rate, and reduce invalid drilling.

Using the LS-DYNA explicit dynamic analysis software, a finite element model of projectile damage in helicopter tail transmission shaft was established with the Johnson-Cook intensity model. The dynamic response of the tail transmission shaft during bullet penetration was simulated dynamically, revealing that projectile damage is the primary mode of failure. Three typical angles were selected to simulate the penetration process, and results indicate that compared to vertical and 45°bullet penetrations, tail transmission shaft damage is more severe.

For the new marine Ti6321 titanium alloy, the penetration tests were carried out under vertical and oblique penetration conditions. The ballistic properties of Ti6321 titanium alloy with different structures and the macro and micro damage characteristics of the target were obtained. The influence of the structure on the ballistic performance and failure mechanism of the titanium alloy target plate was analyzed. The results show that Ti6321 titanium alloy exhibits different properties under vertical and oblique penetration conditions. In the vertical penetration test, the absolute penetration depth and the average crater diameter of the equiaxed target plate are smaller than those of the bimodal and Widmanstatten structure, which show a better resistance to vertical penetration. In the oblique penetration, the safety angle of the bimodal structure was smaller and showed better resistance to the oblique penetration.

The Nasep and Huns members of the Urusis Formation (Nama Group), southern Namibia, preserve some of the most diverse trace-fossil assemblages known from the latest Ediacaran worldwide, including potentially the world's oldest “complex” vertical sediment-penetrating burrows. These sediments record relatively diverse communities of bilaterian metazoans existing before the base of the Cambrian and an increase in the intensity of metazoan ecosystem engineering behaviors that could eventually produce profound changes in the character of the Phanerozoic sedimentary record (the “agronomic revolution”). Despite this, relatively little about this trace-fossil assemblage is known. We explore the Nasep–Huns transition at two localities in the Witputs sub-basin and describe the trace- and body-fossil diversity present in these horizons alongside a paleoenvironmental reconstruction. We document eight unique ichnotaxa from these localities, including well-preserved “probes” potentially left by priapulids. We also report the first occurrence of Corumbella from Namibia, helping to establish a biostratigraphic link between Namibia, Brazil, Paraguay, Iran, and the southwestern United States. Last, we find that several ichnotaxa, in particular small treptichnids, appear to be preferentially preserved on the bases of gutter casts, hinting at the potential existence of an unusual late Ediacaran preservational window with possible implications for timing the first appearance of key bilaterian behaviors.

Upper layer thickness (mixing depth) is an essential parameter for estimating the dissolved inorganic carbon and carbon flux at the water surface based on their association with the vertical flux of dissolved inorganic carbon. Previous studies quantified the mixing depth without SAV meadow or penetration depth in the SAV meadow without stratification and wind stress. However, mixing depth related to interaction with submerged aquatic vegetations (SAVs), stratification, and wind stress has yet to be quantified in the previous studies. Our study is the first to quantify the theoretical mixing depth with SAVs according to wind stress, SAV height, and drag coefficient. Theoretical mixing depth was quantified from modeled vertical temperature profile, vertical profile of horizontal velocity, and gradient Richardson number (Rig,veg). We found that mixing depth at a Rig,veg of 100 demonstrated good agreement with numerical results on average, with the mixing depth estimated in this study (hU,this study) showing high applicability to observations at Komuke Lagoon. Moreover, hU,this study increased with the increasing wind stress and decreasing drag coefficient and SAV height. Further, we found that SAV meadows with stratification and wind stress could be divided into four hydrodynamic regimes: non‐vegetated layers, upper vegetated layers, thermoclines, and benthic boundary layers. Our findings help us estimate mixing depth or vertical flux without complicated numerical simulation and understand flow interaction with SAV, wind stress, and stratification. Plain Language Summary Upper layer thickness (mixing depth) and flow fields are important to estimate the carbon flux (e.g., “blue carbon”) and the transportation of dissolved materials (e.g., dissolved oxygen, dissolved inorganic carbon, dissolved inorganic nitrogen, etc) in submerged aquatic vegetation (SAV) meadows. However, it may not be easy to estimate mixing depth without complex numerical simulations. Additionally, we have not understood the interaction of SAV meadows with stratification, currents, or waves. Our study is the first to quantify the mixing depth analytically and to show the hydrodynamic regimes in SAV meadows with stratification. Our finding helps us to estimate carbon flux and the transportation rate of dissolved materials easily without complicated numerical simulation. Key Points Mixing depth with submerged aquatic vegetation (SAV) meadows was estimated using an average gradient Richardson number 100 SAV meadows with stratification and wind stress were divided into four hydrodynamic regimes Wind stress, SAV, and stratification effects were used to accurately estimate the mixing depth