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Coastal mud belts, which lie parallel to the coast just seaward of the shoreface, are one of the most important settings where shallow‐marine muddy deposits accumulate. However, sedimentary processes and facies distributions of coastal mud belts remain largely uninvestigated. This study uses process‐oriented sedimentology, coupled with provenance analysis and organic geochemistry of sedimentary records at the northern entrance to the Taiwan Strait, to investigate one of the largest such systems in the world, the Changjiang coastal mud belt. Carbon‐14 dates indicate that deposition has been intermittent throughout Marine Isotope Stages 1, 2 and 3, with several cryptic gaps in the muddy succession as a result of exposure or transgressive erosion during periods of lower or rising sea level, respectively. The palaeowater depth of each depositional unit was roughly estimated based on a global sea‐level curve and the elevation and age of the depositional units. Integrated provenance and sedimentology studies suggest that an incised valley most likely cut by the Minjiang, a nearby river draining the Chinese mainland, probably during Marine Isotope Stage 6, was filled with shelf mud during Marine Isotope Stage 3. These results demonstrate that deposition of mud on the Changjiang coastal mud belt was influenced by sea‐level changes that controlled water depth and flow patterns through Taiwan Strait. The Changjiang coastal mud belt migrates landward when sea level rises and moves seaward when sea level drops. In addition, changes in oceanic circulation associated with opening and closing of Taiwan Strait due to sea‐level changes causes significant changes in the source of the mud, with an alternation between sediment contributions from the Changjiang in the north, the nearby Minjiang, and the island of Taiwan to the south‐east. This study also reveals that the Changjiang coastal mud belt deposits are composed of both shallower‐water and deeper‐water facies. The shallower‐water facies predominantly comprises abundant fluid‐mud beds generated by waves and tidal currents. The deeper‐water facies contains shell‐rich mud and bioturbated mud, which were likely deposited by the Chinese coastal current and Taiwan Warm current. The bed types and interpretation of sedimentary processes of the Changjiang coastal mud belt are useful for recognition of ancient deposits of coastal mud belts elsewhere. [ABSTRACT FROM AUTHOR]

The typical nonlinear and asymmetric response of synaptic memristors based on 2D layered materials to positive and negative electrical pulses makes the implementation of accurate deep neural networks very challenging. Here, it has been constructed an integrated circuit (IC) process‐compatible array of modulatable neuromorphic devices based on MoS2 three‐terminal memristors and show that the switching characteristics of this memristor become more gradual and symmetric under electrical excitation, yielding up to 98% linearity of conductance updates in optimized simulations of biological synaptic behavior, achieving long‐term plasticity of 150 s. The linear weight update has better predictability and distinguishability. And all‐solid lithium cobaltate is introduced as an independent modulation channel to obtain a modulatable molybdenum disulfide bandgap by controlling the embedding and disembedding of lithium ions, which effectively reduces the contact potential barrier and more flexibly modulates the artificial synaptic properties based on multiple coupling of light, electricity, and ions. This work lays the foundation for the realization of high‐density and energy‐efficient neuromorphic computing chips. [ABSTRACT FROM AUTHOR]

Enhancement of the conductance range of memristors used in synaptic devices is essential for achieving high‐performance neural networks. Herein, a memristor based on the stack structure of TiN/AlOx/AlOy/ITO is designed to enhance the conductance range. The AlOx/AlOy devices exhibit pseudointerface switching characteristics with higher switching ratios and reliability under a compliance current of 1 mA. The high‐resistance state/low‐resistance state ratio of the AlOx/AlOy devices increases from 11.4 to 128.6 compared with the AlOx devices. Accompanied by high‐conductance linearity, the conductance range increases from 36–202 to 25–280 μS simultaneously. Based on the related electrical properties and microstructure analysis, the regulation mechanism of the formation and rupture of conductive filaments by the oxygen concentration gradient is demonstrated. Simulations using the Modified National Institute of Standards and Technology (MNIST) handwritten recognition data set prove that the AlOx/AlOy memristor can operate with a learning accuracy of 91.07%. [ABSTRACT FROM AUTHOR]

Storage‐class memory and advanced neuromorphic‐related applications place an urgent requirement on large‐scale, highly compacted memristor array. However, crosstalk issue constrains the addressing accuracy and effective data scale of current array‐level memristor, which is detrimental to the industrial realization. Herein, scalability and physical processes of Al/AlN/W self‐rectifying memristor are investigated. The devices exhibit improved rectification ratio from 94 to 2600, switching ratio from 286 to 6099, higher uniformity, reliability, and nonvolatility by scaling the size from 10 to 5 µm. The application of aluminum nitride as active layer material not only makes the electrical properties more sensitive to the external electric field, but also dominates the switching process by constructing nitrogen vacancy conducting filaments, as demonstrated by a combination of scalability and mechanistic analysis. The high‐scaled AlN‐based self‐rectifying memristor exhibits a maximum effective array size of N = 14 372, which is 53 times enhancement compared to 10 µm size cells. The Al/AlN/W self‐rectifying memristor is confirmed to have a strong ability to suppress sneak currents and has the potential to serve large‐scale array‐level applications. [ABSTRACT FROM AUTHOR]

Hyperpycnal flows are important agents for transporting detrital sediments from rivers to oceans. Previous studies often assumed that the deposits of flood‐controlled delta fronts would be dominated by graded sand with common hummocky cross‐stratification. This study documents, for the first time, hybrid event beds and plumite deposits inside the succession of a modern delta front. This delta in the Taiwan Strait is fed by the Choshui River, which is considered a highly efficient sediment transport system with individual floods with extremely high suspended sediment concentrations. The deltaic event beds recorded in the core were interpreted as hyperpycnal flow‐generated hybrid event beds and turbidites triggered by hypopycnal flows. Accelerator Mass Spectrometry 14C dating, grain‐size analysis and measurements of stable isotopic composition of organic matter were conducted to delineate the depositional process of the recognized beds. The internal subdivisions of the hybrid event beds were differentiated mainly based on sedimentary textures, including cohesive mud content, sand content and sorting. The disorganized portion (division H3) appears internally chaotic and contains large rafted substrate clasts but also displays an upward increase in dispersed cohesive mud from 35% (division H3a) to 50% (division H3b). In contrast, massive H1 divisions are characterized by much lower cohesive mud of ca 8%. The vertical arrangement between depositional facies allows the discrimination of three hybrid event bed types. The stable carbon isotopic composition of the organic matter reveals that the cohesive mud in each division of the hybrid event beds was sourced from marine substrate, rather than supplied by the original hyperpycnal flows. Therefore, the hybrid event beds are generated by energetic hyperpycnal flows, which can delaminate the muddy sea‐floor and incorporate large quantities of substrate fragments. The bulking of erosional hyperpycnal turbulent flow forces flow transformation and generates a more cohesive flow with a turbulent, dense head and trailing bipartite debris flow. The occurrence of hybrid event beds in modern shallow delta front settings is also an important novelty, implying a high density of hyperpycnal flows at the mouth of sediment‐laden rivers as well as the crucial impact of substrate entrainment on the development of hybrid event beds. [ABSTRACT FROM AUTHOR]

Ultrathin 2D semiconductor materials have attracted tremendous attention due to their potential application in neuromorphic computing, especially for electronic devices with high stability and low energy consumption. Two‐terminal memristors cannot extend the range of functionalities for complex neuromorphic applications due to their inherent single presynaptic input; thus three‐terminal synaptic transistors based on monolayer monocrystalline‐MoS2 films grown by chemical vapor deposition (CVD) are fabricated in this work. Importantly, there are two modes including drain and gate dual tunability available in nonvolatile memory functions. Both drain terminal and gate terminal can be used as presynaptic inputs to successfully simulate excitatory/inhibitory postsynaptic current (EPSC/IPSC), spike‐amplitude‐dependent plasticity (SADP), spike‐timing‐dependent plasticity (STDP), and long‐term plasticity (LTP) of biological synapses, providing multiple degrees of freedom for synaptic weight modulation. The conductance modulation of drain and gate terminals can be attributed to the migration and charges trapping/detrapping process of sulfur vacancies. Using monocrystalline‐MoS2 films, the device not only attains a lower operation voltage and a higher endurance (5000 cycles), but exhibit low energy consumption during the LTP process (≈3.75 pJ) with the gate terminal, indicating more flexibility and great potential of complex neuromorphic application. [ABSTRACT FROM AUTHOR]

Species have evolved unique mechanisms to combat the effects of oxidative stress inside cells. A particularly devastating consequence of an unhindered oxidation of membrane lipids in the presence of iron results in cell death, known as ferroptosis. Hallmarks of ferroptosis, including peroxidation of polyunsaturated fatty acids, are conserved among animals and plants, however, early divergence of an ancestral mammalian GPX4 (mGPX4) has complicated our understanding of mechanistic similarities between species. To this end, we performed a comprehensive phylogenetic analysis and identified that orthologous Arabidopsis GPXs (AtGPXs) are more highly related to mGPX4 than mGPX4 is to other mammalian GPXs. This high degree of conservation suggested that experimental substitution may be possible. We, therefore, ectopically expressed AtGPX1-8 in ferroptosis-sensitive mouse fibroblasts. This substitution experiment revealed highest protection against ferroptosis induction by AtGPX5, as well as moderate protection by AtGPX2, −7, and −8. Further analysis of these cells revealed substantial abatement of lipid peroxidation in response to pharmacological challenge. The results suggest that the presence of ancestral GPX4 resulted in later functional divergence and specialization of GPXs in plants. The results also challenge a strict requirement for selenocysteine activity and suggest thioredoxin as a potent parallel antioxidant system in both plants and mammals. [ABSTRACT FROM AUTHOR]

A Ni3V2O8/C nanocomposite (nano‐NVO/C) is prepared using a facile solvothermal and postcalcination method, in which polyvinylpyrrolidone (PVP) is adopted as the carbon source and simultaneously prevents the aggregation of Ni3V2O8 nanoparticles to enable in situ formation of highly dispersed Ni3V2O8 nanoparticles around amorphous C. Microstructural characterization shows that elastic amorphous C serves as filler to fill the voids within Ni3V2O8 nanoparticles, bridging the Ni3V2O8 nanoparticles, improving electron transport ability, and withstanding the crystal stress coming from Li+ insertion/extraction. As a consequence, the electrochemical performances including discharge capacity, cycling stability, and rate capacity of nano‐NVO/C are greatly enhanced, delivering a superior cycling capacity of 1284 mA h g−1 at a current density of 0.3 A g−1 after 300 cycles. Electrochemical kinetics studies show that the charge storage in nano‐NVO/C is controlled by the pseudocapacitive mechanism. [ABSTRACT FROM AUTHOR]

The East China Sea Shelf has an unusually wide and low gradient shelf, supplied from sediment‐charged rivers and large river delta systems, with bottom currents sweeping the sea floor and located in the path of strong typhoons. Sediment gravity flow deposits, including four hybrid event beds and a high density turbidite, are identified in a core from the mid‐shelf of the East China Sea. The hybrid event beds typically comprise three or two internal divisions from the base to the top: (i) H1, H3 and H5; or (ii) H3 and H5. Radiocarbon ages of the hybrid event beds were in the range of 3821 to 8526 yr bp. Based on correlation with surrounding cores, the hybrid events may have happened at any time between 1930 yr bp and 3890 yr bp. The δ13C values in hybrid event beds together with bathymetry data suggest local erosion on the shelf. The average δ13C value for the H1 division is similar to the H3 division in the hybrid event beds, implying that the organic matter in the H1 and H3 divisions may come from the same source area. Cross‐plots of upper continental crust normalized rare earth elements in the five units reveal that the sediment source of the four hybrid event beds and the turbidite was ultimately primarily from Korean rivers. Partial transformation from a moderate‐strength debris flow with the additional role of erosional bulking can explain occurrences of hybrid event beds on the East China Sea Shelf. The data indicate that hybrid sediment gravity flow deposits were sourced from intra‐shelf failures and subsequently transformed and deposited as hybrid event beds. The study shows that hybrid sediment gravity flows and turbidity currents may not necessarily indicate proximity to a major fluvial or deltaic system and that intra‐shelf sedimentation can be a sediment source. It is unlikely that the debris flows and turbidity currents were triggered by a hyperpycnal flow or tsunami, because both can carry continental and/or coastal signals which have not been recognized in the core. Typhoons are the probable triggering mechanism. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalytic hydrogen evolution from water splitting using solar energy is one of the most potential strategies for settling the energy crisis, but a bottleneck is occurred in developing a highly efficient photocatalyst. Herein, we successfully fabricated a tubular g‐C3N4 with nitrogen defects (including both nitrogen vacancies and cyano groups) and extended π‐conjugated system, wherein the nitrogen defects and extended π‐conjugated system were conveniently introduced during thermal polymerization of the pyridinium alkaline ionic liquid‐modified hydrogen‐bonding melamine‐cyanuric acid supramolecular (PHMCS) pre‐aggregates towards carbon nitride with hexagonal cylinder morphology formed by the pyridinium alkaline ionic liquid‐assisted hydrothermal process of low‐cost melamine, in which the added trace pyridinium alkaline ionic liquid serves as an all‐rounder with three roles including the promoting agent towards the transformation of melamine to cyanuric acid for constructing PHMCS, nitrogen defects making agent, and the electronic‐tuning agent regarding of the as‐formed carbon nitride. The tubular structure enhances the light scattering and improves the accessibility of active sites. Meanwhile, the high charge transfer efficiency, broad optical absorption region, and suitable energy band positions are related to both the introduction of nitrogen defects by alkali of ionic liquid and the extended π‐electron delocalization in the conjunction carbon nitride networks. As a consequence, the resulted carbon nitride using optimized amount of pyridinium alkaline ionic liquid (AIL‐2.0‐CN) photocatalyst exhibited a high hydrogen evolution rate of 1284 μmol h−1 g−1 (λ>420 nm) with an apparent quantum efficiency of 4.2 % at 420 nm, which is 13.6 times higher than that of bulk g‐C3N4 (B−CN), and even 3.5 folds much higher than the one (SHPY−CN) prepared by the similar process to that for AIL‐2.0‐CN except for the replacement of pyridinium alkaline ionic liquid by a mixture containing a corresponding amount of pyridine and sodium hydroxide, suggesting the promoting effect resulting from the unique characteristic of pyridinium alkaline ionic liquid. Based on the unique physicochemical properties and the molecules‐ adjustability, the developed alkaline ionic liquid assisted strategy can open an avenue for designing and preparing excellent g‐C3N4 based photocatalysts with tunable geometric and electronic structures for solar hydrogen production. All‐round talent! Pyridinium alkaline ionic liquid serves as an all‐rounder to fabricate graphitic carbon nitride with nitrogen defects (nitrogen vacancies and cyano groups) and extended π‐conjugated system, generating a highly efficient photocatalyst for solar hydrogen production under visible light irradiation with 1284 μmol h−1 g−1 (λ>420 nm) of hydrogen evolution rate (13.6 times higher than that of bulk g‐C3N4) and 4.2 % of apparent quantum efficiency at 420 nm. [ABSTRACT FROM AUTHOR]

This paper presents the current body of knowledge regarding the evolution of a braided–meandering system in the southern Junggar Basin, north‐west China, based on the preserved architecture evidences. The response to climate change was also discussed. Herein, 10 types of lithofacies are summarized, including information of their primary sedimentary structures, characteristic lithology, and geometry. This study focuses on recognizing the architectural elements within the channels (migrating channel: CHm, switching channel: CHs, transiting channel: CHt, and filling channel: CHf), the bar units (downstream accretion: DA, lateral accretion: LA, unit bar: UB, and compound bar: CB), and fine‐grained clastic deposits (floodplain fines: FF and overbank fines: OF). Three representative sections of outcrops were selected, and detailed observation and analysis of these sections revealed 3 stages can be divided: the braided stage, in which the deposits show an evidence of CHm, DA elements which are the mainly architectural elements, multichannel with aggradational filling; The transformation between braided–meandering stage, during which the fluvial system consists of CHt and CHm elements with lateral accretion; and meandering stage which is characterized by dominance of CHm, LA elements, and the channels become isolated and meandering. Finally, this paper concludes with an interpretation of climate events as manifested by the fluvial archives of the colours of sedimentary rocks, special mineral, palaeontology, geochemistry spanning the Middle–Upper Jurassic (between 166.1 and 152.1 Ma). [ABSTRACT FROM AUTHOR]

Abstract: The Shan 2 Member, Shan 1 Member and He 8 Member of the Mid–Late Permian Shanxi and lower Xiashihezi formations, in the southeastern Ordos Basin, together comprise ∼150 m of deltaic deposits. This sequence records an overall evolution from deep marine environment to shallow lake associated with braided river, braided river delta and meandering river delta. Core description, well log interpretation, and stable isotope analysis, including carbon, oxygen and strontium, were conducted to understand the sedimentary evolution of Shan 2 to He 8 Member. The Shanxi Formation, which consists of the Shan 2 and Shan 1 members, is characterized by a tidal‐influenced meandering river delta environment and a higher δ13C value and 87Sr/86Sr ratio and a lower δ18O value. The He 8 Member, the basal part of the Xiashihezi Formation, is featured by a braided river to braided river delta system and a lower δ13C value, 87Sr/86Sr ratio, and a higher δ18O value. Four third‐order depositional sequences separated by five sequence boundaries are determined. Coarsening upward sequences of the Shan 2 Member–He 8 Member indicate a general regression trend, which can be correlated to global sea‐level fall occurring during the Roadian–Wuchiapingian, as also evidenced by previous published zircon U–Pb results. The coal‐bearing sequence (Shanxi Formation) to non‐coal‐bearing sequence (He 8 Member), as well as a decrease of 87Sr/86Sr, suggest a trend from humid to arid climates. A combined effect of sea‐level drop and a small uplift at the end of Shanxi Formation are proposed. [ABSTRACT FROM AUTHOR]

Halide perovskite materials have come to the forefront of optoelectronics recently owing to their excellent light absorbing and emitting properties. Despite their excellent properties there are still problems that need to be overcome such as short operating lifetimes, and an observed hysteresis behavior in their current-voltage characteristics. It is found that these challenges could be overcome by developing a deterministic nucleation process using gold as a nucleation promoter to control the grain size of the perovskite layer. It is shown that this deterministic nucleation process can be expanded across multiple perovskite systems and can be used to achieve extremely uniform and large grain sizes within the perovskite layer. These large perovskite grains exhibit enhanced stability compared to current state-of-the-art nanocrystalline films, and exhibit no hysteresis in their I- V characteristics which is key if commercialization of perovskites is to be realized. [ABSTRACT FROM AUTHOR]

BACKGROUND Momordica charantia (MC) has been used for treating diabetes mellitus from ancient times in Asia, Africa and South America. There are many MC accessions in local markets. Polypeptide-P as a main hypoglycemic component in MC was first studied in this experiment to illustrate the different contents in MC of different accessions and different harvesting times. RESULTS Nineteen MC accessions collected from different regions were clustered into three groups using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) molecular markers. Content of polypeptide-P in the tested MC accessions was detected by western blot (WB) method. The WB results revealed that polypeptide-P was detected in MC accessions harvested in June and July but not in September and October. Furthermore, Polypeptide-P content corresponded well with the MC accessions. CONCLUSION Our results suggest that the MC accessions and the harvesting times or the weather during harvest play significant roles in high content of polypeptide-P. [[ArtCopyrightmsg]] [ABSTRACT FROM AUTHOR]

Background: Studies comparing the procedural and clinical outcomes of catheter ablation for atrial fibrillation (AF) guided by CartoMerge and that by Carto have achieved mixed results (Carto, Biosense Webster, Diamond Bar, CA, USA). We collected these studies and conducted a meta-analysis to determine whether CartoMerge results in better procedural and clinical outcomes. Methods and Results: Three randomized controlled trials and two controlled observational studies were collected for analysis. The clinical and procedural outcomes of interest were AF recurrence after catheter ablation, major complications, procedure durations, and fluoroscopy time. Meta-analysis was performed using RevMan 5.0.18 software (The Cochrane Collaboration, Copenhagen, Denmark) and pooled estimates of effect were reported as risk ratios with 95% confidence intervals (CI). The overall results of this meta-analysis indicate that catheter ablation for AF guided by CartoMerge is insignificantly associated with a decreased risk of recurrences (RR = 0.76; 95% CI: 0.55-1.04; P = 0.09) and major complications (RR = 0.73; 95% CI: 0.37-1.45; P = 0.37) compared with that by Carto. Conclusion: The image integration using CartoMerge guiding catheter ablation for AF does not improve the main clinical outcomes significantly compared with that by Carto in centers with experienced operators. (PACE 2012; 35:1242-1247) [ABSTRACT FROM AUTHOR]

The article discusses a study which aimed to present an efficient method to prepare the well-defined polystyrene-grafted multiwalled carbon nanotubes (MWNT) via the radical coupling reaction. The two radical systems presented in the study resulted in the grafting of polystyrene (PS) chains onto MWNTS. Transmission electron microscopy (TEM) analysis showed that the MWNT are enveloped by the polymer molecules.

Herein, dual‐functional nonvolatile and volatile memory occurrence in memristor based on oxide heterostructures is shown. The chemical composition of material is investigated and electrical measurements are performed to indicate the resistive switching stability under consecutive voltage sweep. The device shows robust nonvolatile memory switching (greater than 105 sweep cycles) and self‐compliant volatile threshold switching (approximately 105 nonlinearity) functions. Moreover, the underlying mechanism of the phenomenon is investigated to uncover how the two resistive switching modes happen. This work can provide a reference toward the design of dual‐functional memristors based on oxide heterostructures. [ABSTRACT FROM AUTHOR]

A facile and scalable approach is firstly presented to fabricate novel O‐doped nitrogen defective porous g‐C3N4 nanosheets (PNV‐CN) through thermal polymerization of a guanylurea nitrate (GLUN) precursor that forms by a nitric acid assisted heating reaction process of dicyandiamide (DCDA), in which nitrate ions act as the intensified gas template function for producing pores and carbon nitride nanosheet structures and the oxidant for forming nitrogen defects. PNV‐CN demonstrates a high visible light photocatalytic activity of 62.4 μmol h−1 and an apparent quantum efficiency of 4.0% at 420 nm with 17.3 and 5.5 times higher hydrogen evolution rate (HER) than bulk g‐C3N4 (B‐CN) prepared by thermal polymerization of DCDA and the loose g‐C3N4 (LB‐CN), prepared via thermal polymerization of a mixture (DMDN) consisting of dicyandiamide nitrate (DN), GLUN, and their hydrogen‐bonding macromolecular compounds by drying the physical mixture of DCDA and nitric acid, respectively. The outstanding photocatalytic properties of PNV‐CN for visible light‐driven hydrogen evolution originate from the enhanced charge separation and migration, extending visible light absorption tails, promoting recombination of charge carriers, increased active sites, and strengthened mass transfer process that results from the synergistically promoting effect of hierarchical porous morphology, as‐formed nitrogen defects, O‐doping and the unique nanosheet structure. [ABSTRACT FROM AUTHOR]

A porous halide perovskite–polymer nanocomposite is developed using a freeze‐drying process. Such a composite shows strong fluorescence quenching after exposure to explosive nitroaromatics, nitroamines, and nitrate esters with a sensitivity of a few nanograms. In addition, this composite is robust against moisture and solvents, showing negligible change in fluorescence intensities after submersion in water, alcohol, and acid, base, and salt solutions. Transient absorption spectroscopy studies further disclose that the explosive chemical introduces more trap states into the perovskite that contributes to fluorescence quenching of the perovskite. Porous halide perovskite–polymer nanocomposite foam is developed through a freeze‐drying process. This nanocomposite exhibits strong photoluminescence under UV excitation. Fluorescence quenching of the foam is observed with a sensitivity of a few nanograms after contacting to common explosives including nitroaromatics, nitroamines, and nitrate esters. The nanocomposite foam is found not responsive to water, alcohol, and common acid, base, and salt solutions. [ABSTRACT FROM AUTHOR]