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Rifted margins often show apparent along-strike variations at the continent-ocean transition (COT) region, typically occurring gradually over hundreds-to-thousands of km between the “magma-rich” and “magma-poor” endmembers. In contrast, comparatively smaller-scale lateral variabilities of rifting structure and faulting style in hyper-thinned continental crust are not yet well described. The South China Sea (SCS) was recently defined as the archetype of a new “intermediate-type” margin with neither excess magmatism nor mantle exhumation. However, along-strike crustal variations along this new type of margin are still little explored. Based on previously unpublished 2D grid of seismic reflection lines and overlapping 3D seismic volumes, we have investigated the crustal structure, faulting style, and the lower crustal reflectivity along ∼400 km of the mid-northern SCS margin. Our new maps of crystalline-crust thickness and top basement show that the SCS extension developed in two segments with contrasting tectonic styles separated by a narrow boundary. The eastern domain, resembling a wide-rift model, displays low-angle detachment faults and high-velocity lower crust mainly associated with syn-rift magmatism indicating weak crustal rheology. The neighboring western domain, resembling a narrow rift model, displays steep crustal-scale faults indicating comparatively strong rheology. The change from wide to narrow rift—or weak to strong rheology—occurs abruptly, which appears at odds with the current conventional wisdom of mostly gradual transitions over a long distance between rift models. We speculate that the inherited heterogeneity in mantle composition and 3D melt focusing effect may drive this abrupt along-strike variability in the mid-northern SCS

Chemokines are cytokines with chemoattractant capacities that exert their physiological functions through the binding of chemokine receptors. Thus, chemokine and receptor complexes exert important roles in regulating development and homeostasis during routine immune surveillance and inflammation. Compared to mammals, the physiology and structure of chemokine receptors in fish have not been systematically studied. Furthermore, the salmonid-specific whole genome duplication has significantly increased the number of functional paralogs of chemokine receptors. In this context, in the current study, trout exhibited 17 cxcr genes, including 12 newly identified and 5 previously identified receptors. Interestingly, gene expression of brain cxcr1 and cxcr4, kidney cxcr3 and cxcr4, and spleen cxcr3, cxcr4, and cxcr5 subtypes were altered by bacterial infection, whereas brain cxcr1, kidney cxcr1 and cxcr7, and liver cxcr2, cxcr3, and cxcr4 subtypes were changed in response to environmental changes. Based on protein structures predicted by ColabFold, the conserved amino acids in binding pockets between trout CXCR4.1 subtypes and human CXCR4 were also analyzed. Our study is valuable from a comparative point of view, providing new insights into the identification and physiology of salmonid chemokine receptors.

The electrochemical reduction of biomass-derived feedstocks provides a sustainable platform for the synthesis of a wide range of chemical commodities and biofuels. Despite their interest, the optimization of reaction conditions, the screening of electrode materials, and the mechanistic understanding of these processes lag well behind other chemical routes. Here, we focus on the electrochemical self-coupling of benzaldehyde (BZH) to hydrobenzoin (HDB) using semiconductor electrocatalysts with nanosheet morphologies. By testing several semiconductor materials, a correlation is observed between their band gap and the electrochemical potential necessary to maximize selectivity towards HDB in alkaline medium, which we associate with the charge accumulation at the semiconductor surface. N-type CuInS2 provides the highest conversion rate at 0.3 mmol cm−2h−1 with a selectivity of 98.5 % at −1.3 V vs. Hg/HgO. Additional density functional theory calculations demonstrate a lower kinetic energy barrier at the CuInS2 surface compared with graphitic carbon, proving its catalytic role in the self-coupling reaction of BZH.

Membrane technology has attracted great industrial interest in carbon capture and separation owing to the merits of energy-efficiency, environmental friendliness and low capital investment. Conventional polymeric membranes for CO2 separation suffer from the trade-off between permeability and selectivity. Introducing porous fillers in polymers is one approach to enhance membrane separation performance. Metal-organic frameworks (MOFs), with ordered porous structure and diverse chemical functionalities, are promising fillers to prepare mixed matrix membranes (MMMs) for CO2 separation. However, the main issue of MOF based MMMs in industry is their stability and processability. This review analyses recent work on stable and scalable MOF based MMMs for CO2 separation. The typical stable MOFs, MOF-based MMMs and the scalable MOF synthesis are summarized. A large number of MOF-based MMM suffer from instability upon exposure to contaminants. For that reason, we also discuss the use of covalent organic frameworks (COFs) as an alternative to prepare MMMs for CO2 separation, considering their excellent stability and good compatibility with polymers. Finally, a brief conclusion and current challenges on obtaining scalable and stable MMMs are outlined. This review may provide some guidance for designing high performance MMMs for industrial CO2 capture and separation to help achieving carbon neutrality.

The main protease (Mpro) of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle. The covalent Mpro inhibitor nirmatrelvir (in combination with ritonavir, a pharmacokinetic enhancer) and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use. Effective antiviral drugs are needed to fight the pandemic, while non-covalent Mpro inhibitors could be promising alternatives due to their high selectivity and favorable druggability. Numerous non-covalent Mpro inhibitors with desirable properties have been developed based on available crystal structures of Mpro. In this article, we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent Mpro inhibitors, followed by a general overview and critical analysis of the available information. Prospective viewpoints and insights into current strategies for the development of non-covalent Mpro inhibitors are also discussed.

Influenza is an acute respiratory infection caused by influenza viruses (IFV), According to the World Health Organization (WHO), seasonal IFV epidemics result in approximately 3-5 million cases of severe illness, leading to about half a million deaths worldwide, along with severe economic losses and social burdens. Unfortunately, frequent mutations in IFV lead to a certain lag in vaccine development as well as resistance to existing antiviral drugs. Therefore, it is of great importance to develop anti-IFV drugs with high efficiency against wild-type and resistant strains, needed in the fight against current and future outbreaks caused by different IFV strains. In this review, we summarize general strategies used for the discovery and development of antiviral agents targeting multiple IFV strains (including those resistant to available drugs). Structure-based drug design, mechanism-based drug design, multivalent interaction-based drug design and drug repurposing are amongst the most relevant strategies that provide a framework for the development of antiviral drugs targeting IFV.

Obtaining high-resolution images at centimeter-or-longer wavelengths is vital for understanding the physics of jets. We reconstructed images from the M87 22 GHz data observed with the East Asian VLBI Network (EAVN) by using the regularized maximum likelihood (RML) method, which is different from the conventional imaging method CLEAN. Consequently, a bright core and jet extending about 30 mas to the northwest were detected with a higher resolution than in the CLEAN image. The width of the jet was 0.5 mas at 0.3 mas from the core, consistent with the width measured in the 86 GHz image in the previous study. In addition, three ridges were able to be detected at around 8 mas from the core, even though the peak-to-peak separation was only 1.0 mas. This indicates that the RML image’s spatial resolution is at least 30% higher than that of the CLEAN image. This study is an important step for future multi-frequency and high-cadence observations of the EAVN to discuss the more detailed structure of the jet and its time variability. © 2023 by the authors. Licensee MDPI, Basel, Switzerland.

The decomposition of litter and the supply of nutrients into and from the soil are two fundamental processes through which the above- and belowground world interact. Microbial biodiversity, and especially that of decomposers, plays a key role in these processes by helping litter decomposition. Yet the relative contribution of litter diversity and soil biodiversity in supporting multiple ecosystem services remains virtually unknown. Here we conducted a mesocosm experiment where leaf litter and soil biodiversity were manipulated to investigate their influence on plant productivity, litter decomposition, soil respiration, and enzymatic activity in the littersphere. We showed that both leaf litter diversity and soil microbial diversity (richness and community composition) independently contributed to explain multiple ecosystem functions. Fungal saprobes community composition was especially important for supporting ecosystem multifunctionality (EMF), plant production, litter decomposition, and activity of soil phosphatase when compared with bacteria or other fungal functional groups and litter species richness. Moreover, leaf litter diversity and soil microbial diversity exerted previously undescribed and significantly interactive effects on EMF and multiple individual ecosystem functions, such as litter decomposition and plant production. Together, our work provides experimental evidence supporting the independent and interactive roles of litter and belowground soil biodiversity to maintain ecosystem functions and multiple services.

Microbial communities in soils are generally considered to be limited by carbon (C), which could be a crucial control for basic soil functions and responses of microbial heterotrophic metabolism to climate change. However, global soil microbial C limitation (MCL) has rarely been estimated and is poorly understood. Here, we predicted MCL, defined as limited availability of substrate C relative to nitrogen and/or phosphorus to meet microbial metabolic requirements, based on the thresholds of extracellular enzyme activity across 847 sites (2476 observations) representing global natural ecosystems. Results showed that only about 22% of global sites in terrestrial surface soils show relative C limitation in microbial community. This finding challenges the conventional hypothesis of ubiquitous C limitation for soil microbial metabolism. The limited geographic extent of C limitation in our study was mainly attributed to plant litter, rather than soil organic matter that has been processed by microbes, serving as the dominant C source for microbial acquisition. We also identified a significant latitudinal pattern of predicted MCL with larger C limitation at mid- to high latitudes, whereas this limitation was generally absent in the tropics. Moreover, MCL significantly constrained the rates of soil heterotrophic respiration, suggesting a potentially larger relative increase in respiration at mid- to high latitudes than low latitudes, if climate change increases primary productivity that alleviates MCL at higher latitudes. Our study provides the first global estimates of MCL, advancing our understanding of terrestrial C cycling and microbial metabolic feedback under global climate change.

Compaction and lack of permeability are common problems in continuously farmed soils and have a negative impact on crop yields. Regulation of the microbial community in the plant rhizosphere has been envisaged as a promising approach to alleviate these physical damages in soil. The effects of Nanobubble oxygen (NBO2) on the soil structure and the bacterial community were investigated using X-ray tomography and 16 S rRNA amplicon sequencing. The results indicated that NBO2 significantly improved the soil structure and permeability. NBO2 increased the total porosity by43.2%, from 18.74% to 26.82%, and the pore connectivity by 355.1%, from 2922 to 13301, respectively. The structural equation model (SEM) demonstrated that NBO2 had direct impacts on soil structure by increasing microbial community diversity and changing interactions among microbial species. In addition, NBO2 directly impacted the soil structure by reducing the formation of soil biofilms and the stability of soil macroaggregates. In addition, the NBO2 treatment indirectly affected the soil structure by altering the community composition and promoting the decomposition of unstable organic carbon, resulting in improved soil porosity and pore connectivity. Our results highlight the efficiency of NBO2 in improving soil structure and provide mechanistic knowledge on the microbial-mediated processes for the improvement of crop yield and quality using oxygenated drip irrigation.

Tropical forests are among the most productive and vulnerable ecosystems in the planet. Several global forestation programs are aiming to plant millions of trees in tropical regions in the future decade. Mycorrhizal associations are known to largely influence forest soil carbon (C) stocks. However, to date, little is known on whether and how different tree mycorrhizal types affect soil respiration (Rs) and C stocks in tropical forests. In this study, we used a three-decade tropical common garden experiment, with three arbuscular mycorrhizal (AM) and three ectomycorrhizal (EM) monocultures, to investigate the impacts of tree mycorrhizal type on Rs and soil C stocks. Associating biotic (e.g. root biomass, litter dynamic, soil microbes) and abiotic factors (e.g. microclimate) were also measured. Our results showed that AM stands supported significantly higher Rs and soil C stock, litter turnover rate and fine root biomass than EM stands. Further statistical analysis displayed that tree mycorrhizal type was the most important factor in regulating Rs and soil C stock compared with other biotic or abiotic factors. Moreover, we found that mycorrhizal type directly and indirectly affected Rs and soil C stocks via fine root biomass and litter dynamic, i.e. litter production, litter standing crop and litter turnover rate. Our findings highlight important effects of tree mycorrhizal type on forest C cycle, suggesting that planting AM tree species could contribute to promotion of soil C stock in tropical ecosystems.

While the contribution of biodiversity to supporting multiple ecosystem functions is well established in natural ecosystems, the relationship of the above- and below-ground diversity with ecosystem multifunctionality remains virtually unknown in urban greenspaces. Here we conducted a standardized survey of urban greenspaces from 56 municipalities across six continents, aiming to investigate the relationships of plant and soil biodiversity (diversity of bacteria, fungi, protists and invertebrates, and metagenomics-based functional diversity) with 18 surrogates of ecosystem functions from nine ecosystem services. We found that soil biodiversity across biomes was significantly and positively correlated with multiple dimensions of ecosystem functions, and contributed to key ecosystem services such as microbially driven carbon pools, organic matter decomposition, plant productivity, nutrient cycling, water regulation, plant–soil mutualism, plant pathogen control and antibiotic resistance regulation. Plant diversity only indirectly influenced multifunctionality in urban greenspaces via changes in soil conditions that were associated with soil biodiversity. These findings were maintained after controlling for climate, spatial context, soil properties, vegetation and management practices. This study provides solid evidence that conserving soil biodiversity in urban greenspaces is key to supporting multiple dimensions of ecosystem functioning, which is critical for the sustainability of urban ecosystems and human wellbeing.

The design of high-temperature ferrimagnetic materials is highly demanded for next-generation functional spintronic devices. Here, we propose that the combination of nonmetallic structural units and magnetic atoms is an effective way to achieve high-temperature magnetism in two-dimensional (2D) materials. The predicted FeP4 monolayer, consisting of quasisquare P4 units, shows intrinsic half-metal ferrimagnetism above room temperature. Each Fe atom is coordinated with four P atoms associated with the surrounding four quasisquare P4 units. First-principles calculations suggest that the FeP4 monolayer presents a Curie temperature of 460 K. More interestingly, the itinerant electrons and the unique quasisquare P4 units act as intermediaries and play an important role in promoting the Ruderman-Kittel-Kasuya-Yosida and superexchange interactions, respectively, which induces a robust ferrimagnetism. Our findings not only shed light on the promising future of 2D magnetic materials, but also are of interest for high-temperature spintronic applications.

Glaciers cover nearly 10% of the Earth's surface and are unique biomes dominated by microbial communities that support key ecosystem processes. The melting of glaciers is among the most conspicuous consequences of global climate change, with impacts on microbial ecology and associated biogeochemistry. However, we are still missing an integrative understanding of microbial biodiversity from divergent habitats associated with glaciers.Here, we compiled global microbiome metadata from 93 representative glaciers over 180 locations and used random forest, microbial ecological networks, and structural equation modeling to evaluate the biodiversity and environmental factors associated with the glacier microbiomes of seven contrasting habitats: water, epilithic biofilm, cryoconite, mat, ice, sediment and permafrost soil.The results showed that microbial diversity largely changed across habitats, with the highest in permafrost soil, followed by sediment, ice, mat, cryoconite, water, and epilithic biofilm. More importantly, we provided critical evidence that the environmental and climatic factors associated with the microbiomes of glaciers varied with glacier habitats. Microbial diversity in water was highly correlated with latitude, cryoconite microbial diversity was significantly (P = 0.01) correlated with pH, and permafrost soil and sediment microbial diversity were mainly explained by temperature (17.05% and 13.37%, respectively).Using ecological association network analysis, we identified some tightly linked common microbial taxa (e.g., Proteobacteria and Bacteroidetes) that were present in all the habitats and were vulnerable to climatic factors, such as temperature and precipitation. This study demonstrated that microbial diversity, drivers and co-occurrence patterns differ among glacier habitats globally, and diverse habitat-dependent glacier microbiomes could serve as early warning sentinels for the study of life on glaciers and its potential future in a warming worl

The multidimensional dynamics of biodiversity and ecosystem function during the rewilding of Mediterranean forests remain poorly understood, limiting our capacity to predict how future restoration efforts may help mitigate climate change. Here, we investigated the changes in multiple dimensions of biodiversity and ecosystem services in a 120-year forest succession after harvest to identify potential trade-offs in multiple dimensions of ecosystem function, and further assess the link between above and below-ground biodiversity and function. We found a positive influence of successional age on not only multiple dimensions of biodiversity and function but also some important trade-offs. Two ecosystem axes of function explained nearly 75.4% of functional variation during ecosystem rewilding. However, while the first axis increased with successional age promoting plant productivity and element stocks, the second axis followed a hump-shaped relationship with age supporting important reductions in nutrient availability and pathogen control in old forests. Our study further revealed a significant positive relationship between plant and soil biodiversity with multiple elements of multifunctionality as forests develop. Moreover, the influence of plant and soil biodiversity were especially important to support a high number of function working at high levels of functioning. Our work provides new insights on the patterns and functional trade-offs in the multidimensional rewilding of forests and further highlights the importance of biodiversity for long-term Mediterranean rewilding.

Although detrimental effects of commuting have been widely researched, little longitudinal evidence can be found regarding whether changes in commuting time and modes cause changes in life satisfaction. This study examines the relationships of life satisfaction with commuting from a longitudinal perspective. The effects of built environment are also examined. Using longitudinal survey data from 4505 respondents in China, the findings show that the increase in commuting time associates with losses in life satisfaction. Switching from non-active modes to active modes associates with increases in life satisfaction. Nonetheless, switching from active modes to non-active modes only reduces life satisfaction for people who experienced changes in some specific built environment attributes (e.g., increasing population density). Most changes in built environment associate with life satisfaction changes. The findings suggest that policy and planning efforts to promote active commuting and reduce commuting time (e.g., providing walkable and cyclist-friendly environment and promoting job–housing balance) should continue.

Gastric cancer (GC) is one of the commonest cancers with high morbidity and mortality in the world. How to realize precise diagnosis and therapy of GC owns great clinical requirement. In recent years, artificial intelligence (AI) has been actively explored to apply to early diagnosis and treatment and prognosis of gastric carcinoma. Herein, we review recent advance of AI in early screening, diagnosis, therapy and prognosis of stomach carcinoma. Especially AI combined with breath screening early GC system improved 97.4 % of early GC diagnosis ratio, AI model on stomach cancer diagnosis system of saliva biomarkers obtained an overall accuracy of 97.18 %, specificity of 97.44 %, and sensitivity of 96.88 %. We also discuss concept, issues, approaches and challenges of AI applied in stomach cancer. This review provides a comprehensive view and roadmap for readers working in this field, with the aim of pushing application of AI in theranostics of stomach cancer to increase the early discovery ratio and curative ratio of GC patients.

Nanozymes with inherent enzyme-mimicking catalytic properties combat malignant tumor progression via catalytic therapy, while the therapeutic efficacy still needs to be improved. In this work, ultrasmall platinum nanozymes (nPt) in a confined domain of a wormlike pore channel in gold nanobipyramidal–mesoporous silica dioxide nanocomposites, producing nanozyme carriers AP-mSi with photoenhanced peroxidase ability, are innovatively synthesized. Afterward, based on the prepared AP-mSi, a lung-cancer nanozymes probe (AP-HAI) is ingeniously produced by removing the SiO2 template, modifying human serum albumin, and loading atovaquone molecules (ATO) as well as IR780. Under NIR light irradiation, inner AuP and IR780 collaborate for photothermal process, thus facilitating the peroxidase-like catalytic process of H2O2. Additionally, loaded ATO, a cell respiration inhibitor, can impair tumor respiration metabolism and cause oxygen retention, hence enhancing IR780's photodynamic therapy (PDT) effectiveness. As a result, IR780's PDT and nPt nanozymes' photoenhanced peroxidase-like ability endow probes a high ROS productivity, eliciting antitumor immune responses to destroy tumor tissue. Systematic studies reveal that the obvious reactive oxygen species (ROS) generation is obtained by the strategy of using nPt nanozymes and reducing oxygen consumption by ATO, which in turn enables lung-cancer synergetic catalytic therapy/immunogenic-cell-death-based immunotherapy. The results of this work would provide theoretical justification for the practical use of photoenhanced nanozyme probes.

In this study, we propose a method for wind speed retrieval using a random forest (RF) algorithm for Cyclone Global Navigation Satellite System (CYGNSS) data. We first compared CYGNSS data with soil moisture active passive (SMAP) data and found a certain deviation in the CYGNSS “young sea, limited fetch” (YSLF) data product for high winds. Then, we used SMAP as the “ground truth” to train an RF model and applied it to the wind speed retrieval of CYGNSS data. The experimental results show that using the RF algorithm for wind speed retrieval can eliminate noise in the CYGNSS YSLF wind speed data and improve retrieval accuracy. In addition, we explored the impact of different input parameter combinations on model performance and found that using an 11-parameter model in CYGNSS wind speed retrieval can achieve optimal performance. This can provide a valuable reference for rapid near-real-time retrieval of tropical cyclones using CYGNSS.

In this study, complete (i.e., including all vibrational quantum numbers in an N2 vibrational ladder) data sets of vibration-to-vibration and vibration-to-translation rate coefficients for N2-N2 collisions are explicitly computed along with transport properties (shear and bulk viscosity, thermal conductivity, and self-diffusion) in the temperature range 100-9000 K. To reach this goal, we improved a mixed quantum-classical (MQC) dynamics approach by lifting the constraint of a Morse treatment of the vibrational wave function and intramolecular potential and permitting the use of more realistic and flexible representations. The new formulation has also allowed us to separately analyze the role of intra- and intermolecular potentials on the calculated rates and properties. Ab initio intramolecular potentials are indispensable for highly excited vibrational states, though the Morse potential still gives reasonable values up to v = 20. An accurate description of the long-range interaction and the van der Waals well is a requisite for the correct reproduction of qualitative and quantitative rate coefficients, particularly at low temperatures, making physically meaningful analytical representations still the best choice compared to currently available ab initio potential energy surfaces. These settings were used to directly compute the MQC rates corresponding to a large number of initial vibrational quantum numbers, and the missing intermediate values were predicted using a machine learning technique (i.e., the Gaussian process regression approach). The obtained values are reliable in the wide temperature range employed and are therefore valuable data for many communities dealing with nonlocal thermal equilibrium conditions in different environments.

Heteroatom doping serves as an important strategy to improve the oxygen evolution reaction (OER) activity of transition-metal compounds, while the investigation of intrinsic active sites and mechanisms remains insufficient. In this work, a facile cation regulation strategy is reported to boost the OER activity of metal sulfides via pyrolysis of the Ni-Co bimetallic metal-organic framework. The obtained Ni-substituted CoS nanoparticles on nitrogen-doped mesoporous carbon (Ni-CoS/NC) catalyst achieves a current density of 10 mA cm−2 at a small overpotential of 270 mV with a Tafel slope of 37 mV dec−1 in 1.0 mol L−1 KOH. Through a combination of spectroscopy study and theoretical computations, the activity origin is revealed at the atomic level. The CoxNi1–xOOH serves as the real active site for the OER generated by the Ni-CoS/NC reconstruction under oxidation potential during OER. The Ni substitution results in a strong electronic interaction between the two metals, thus generating more negatively charged Co atoms and more positively charged Ni atoms in the electrocatalyst. The metal sites with regulated electronic structure exhibit enhanced surface adsorption of OOH* and reduce the OER overpotential. Meanwhile, the conductive porous carbon scaffold facilitates electron transfer, mass diffusion, and the accessibility of active sites. This work not only provides a feasible cation regulation strategy for the design of high-performance electrocatalysts for low-cost energy storage and conversion systems, but also yields fresh insight into the activity enhancement mechanisms and intrinsic active sites.

With the intensification of climate warming, more frequent and hotter droughts are a significant risk to forest ecosystems around the globe, including temperate biomes. To accurately predict the response of forests to drought, it is necessary to provide comprehensive information on the resilience of tree growth, its spatiotemporal changes and drivers. This information is often lacking for broadleaf species in temperate regions. To fulfill this aim, we analyzed 3177 ring-width series from 1981 trees covering 40 sites for four dominant broad-leaf tree species (Fraxinus mandshurica, Phellodendron amurense, Juglans mandshurica, and Quercus mongolica) in temperate forests in northeastern China. We quantified the resilience (resistance and recovery) of tree growth to extreme droughts. Minimum temperatures in most seasons and warm conditions and drought stress in early summer were the main factors limiting growth. Among the four tree species, Q. mongolica had the weakest growth resistance to drought and the fastest growth recovery from drought. Juglans mandshurica had a significantly (p < 0.05) higher drought resilience than F. mandshurica and P. amurense. Tree resilience presented a clear spatial pattern driven by differences in site condition and local climate. The resistance (recovery) to drought decreased (increased) with increasing latitude and longitude, and increased (decreased) with elevation. Q. mongolica exhibited a decrease in resistance and increase in recovery through time, whereas the other three tree species showed the opposite pattern. Fraxinus mandshurica, J. mandshurica, and Q. mongolica had high resistance (recovery) in warmer-wetter (colder-drier) regions. In contrast, P. amurense had reduced recovery in cold sites and low resistance in warm sites. The resistance and recovery indices of these sympatric tree species confirmed that different tree species have distinct strategies to cope with drought that is influenced by tree condition and local environme

Located at crystal voids, interstitial anion electrons (IAEs) have diverse topologies, which may be tuned to achieve different properties. Elucidating the role of IAEs in electron-phonon coupling (EPC), and using it to design electride superconductors, leads to the current prediction of superconducting Li8Au at high pressure. We suggest that the occurence of high-temperature superconductivity in electrides requires high-symmetry structures with hydrogenlike cages, an electron acceptor element to balance charges, and isolated IAEs coupled with medium-frequency vibrations. The uniquely designed Li8Au electride has a NaCl-type (B1) lattice, with atomic Au and cubic Li8 cages as bases. Isolated IAEs are formed at the cage centers, with extra charges taken up by Au. These octahedrally coordinated IAEs have a p-orbital-like attribute and are strongly coupled with atomic vibrations in the Li8 cages. The strong EPC in Li8Au results in a calculated Tc of 73.1 K at 250 GPa, which is the highest Tc reported to date for all the electrides. A slight substitutional Pt doping can enhance the Tc of Li8Au to exceed liquid nitrogen temperature.

Three-dimensional (3D) chromatin organization is highly dynamic during development and seems to play a crucial role in regulating gene expression. Self-interacting domains, commonly called topologically associating domains (TADs) or compartment domains (CDs), have been proposed as the basic structural units of chromatin organization. Surprisingly, although these units have been found in several plant species, they escaped detection in Arabidopsis (Arabidopsis thaliana). Here, we show that the Arabidopsis genome is partitioned into contiguous CDs with different epigenetic features, which are required to maintain appropriate intra-CD and long-range interactions. Consistent with this notion, the histone-modifying Polycomb group machinery is involved in 3D chromatin organization. Yet, while it is clear that Polycomb repressive complex 2 (PRC2)-mediated trimethylation of histone H3 on lysine 27 (H3K27me3) helps establish local and long-range chromatin interactions in plants, the implications of PRC1-mediated histone H2A monoubiquitination on lysine 121 (H2AK121ub) are unclear. We found that PRC1, together with PRC2, maintains intra-CD interactions, but it also hinders the formation of H3K4me3-enriched local chromatin loops when acting independently of PRC2. Moreover, the loss of PRC1 or PRC2 activity differentially affects long-range chromatin interactions, and these 3D changes differentially affect gene expression. Our results suggest that H2AK121ub helps prevent the formation of transposable element/H3K27me1-rich long loops and serves as a docking point for H3K27me3 incorporation.

Spiking neural networks (SNNs) are regarded as a promising candidate to deal with the major challenges of current machine learning techniques, including the high energy consumption induced by deep neural networks. However, there is still a great gap between SNNs and the few-shot learning performance of artificial neural networks. Importantly, existing spike-based few-shot learning models do not target robust learning based on spatiotemporal dynamics and superior machine learning theory. In this paper, we propose a novel spike-based framework with the entropy theory, namely, heterogeneous ensemble-based spike-driven few-shot online learning (HESFOL). The proposed HESFOL model uses the entropy theory to establish the gradient-based few-shot learning scheme in a recurrent SNN architecture. We examine the performance of the HESFOL model based on the few-shot classification tasks using spiking patterns and the Omniglot data set, as well as the few-shot motor control task using an end-effector. Experimental results show that the proposed HESFOL scheme can effectively improve the accuracy and robustness of spike-driven few-shot learning performance. More importantly, the proposed HESFOL model emphasizes the application of modern entropy-based machine learning methods in state-of-the-art spike-driven learning algorithms. Therefore, our study provides new perspectives for further integration of advanced entropy theory in machine learning to improve the learning performance of SNNs, which could be of great merit to applied developments with spike-based neuromorphic systems.

Neuromorphic computing is a promising technology that realizes computation based on event-based spiking neural networks (SNNs). However, fault-tolerant on-chip learning remains a challenge in neuromorphic systems. This study presents the first scalable neuromorphic fault-tolerant context-dependent learning (FCL) hardware framework. We show how this system can learn associations between stimulation and response in two context-dependent learning tasks from experimental neuroscience, despite possible faults in the hardware nodes. Furthermore, we demonstrate how our novel fault-tolerant neuromorphic spike routing scheme can avoid multiple fault nodes successfully and can enhance the maximum throughput of the neuromorphic network by 0.9%–16.1% in comparison with previous studies. By utilizing the real-time computational capabilities and multiple-fault-tolerant property of the proposed system, the neuronal mechanisms underlying the spiking activities of neuromorphic networks can be readily explored. In addition, the proposed system can be applied in real-time learning and decision-making applications, brain–machine integration, and the investigation of brain cognition during learning.

Working memory is a fundamental feature of biological brains for perception, cognition, and learning. In addition, learning with working memory, which has been show in conventional artificial intelligence systems through recurrent neural networks, is instrumental to advanced cognitive intelligence. However, it is hard to endow a simple neuron model with working memory, and to understand the biological mechanisms that have resulted in such a powerful ability at the neuronal level. This article presents a novel self-adaptive multicompartment spiking neuron model, referred to as SAM, for spike-based learning with working memory. SAM integrates four major biological principles including sparse coding, dendritic non-linearity, intrinsic self-adaptive dynamics, and spike-driven learning. We first describe SAM's design and explore the impacts of critical parameters on its biological dynamics. We then use SAM to build spiking networks to accomplish several different tasks including supervised learning of the MNIST dataset using sequential spatiotemporal encoding, noisy spike pattern classification, sparse coding during pattern classification, spatiotemporal feature detection, meta-learning with working memory applied to a navigation task and the MNIST classification task, and working memory for spatiotemporal learning. Our experimental results highlight the energy efficiency and robustness of SAM in these wide range of challenging tasks. The effects of SAM model variations on its working memory are also explored, hoping to offer insight into the biological mechanisms underlying working memory in the brain. The SAM model is the first attempt to integrate the capabilities of spike-driven learning and working memory in a unified single neuron with multiple timescale dynamics. The competitive performance of SAM could potentially contribute to the development of efficient adaptive neuromorphic computing systems for various applications from robotics to edge computing.

The causal agent of bacterial wilt, Ralstonia pseudosolanacearum, can cause significant economic losses during tobacco production. Metabolic analyses are a useful tool for the comprehensive identification of plant defense response metabolites. In this study, a gas chromatography-mass spectrometry (GC-MS) approach was used to identify metabolites differences in tobacco xylem sap in response to R. pseudosolanacearum CQPS-1 in two tobacco cultivars: Yunyan87 (susceptible to R. pseudosolanacearum) and K326 (quantitatively resistant). Metabolite profiling 7 days post inoculation with R. pseudosolanacearum identified 88 known compounds, 42 of them enriched and 6 depleted in the susceptible cultivar Yunyan87, while almost no changes occurred in quantitatively resistant cultivar K326. Putrescine was the most enriched compound (12-fold) in infected susceptible tobacco xylem, followed by methyl-alpha-d-glucopyranoside (9-fold) and arabinitol (6-fold). Other sugars, amino acids, and organic acids were also enriched upon infection. Collectively, these metabolites can promote R. pseudosolanacearum growth, as shown by the increased growth of bacterial cultures supplemented with xylem sap from infected tobacco plants. Comparison with previous metabolic data showed that beta-alanine, phenylalanine, and leucine were enriched during bacterial wilt in both tobacco and tomato xylem.

There exists a considerable density of interaggregate grain boundaries (GBs) and intra-aggregate GBs in polycrystalline perovskites. Mitigation of intra-aggregate GBs is equally notable to that of interaggregate GBs as intra-aggregate GBs can also cause detrimental effects on the photovoltaic performances of perovskite solar cells (PSCs). Here, we demonstrate full-scale GB mitigation ranging from nanoscale intra-aggregate to submicron-scale interaggregate GBs, by modulating the crystallization kinetics using a judiciously designed brominated arylamine trimer. The optimized GB-mitigated perovskite films exhibit reduced nonradiative recombination, and their corresponding mesostructured PSCs show substantially enhanced device efficiency and long-term stability under illumination, humidity, or heat stress. The versatility of our strategy is also verified upon applying it to different categories of PSCs. Our discovery not only specifies a rarely addressed perspective concerning fundamental studies of perovskites at nanoscale but also opens a route to obtain high-quality solution-processed polycrystalline perovskites for high-performance optoelectronic devices.

Bacteria have evolved multiple signal transduction systems that permit an adaptation to changing environmental conditions. Chemoreceptor-based signaling cascades are very abundant in bacteria and are among the most complex signaling systems. Currently, our knowledge on the molecular features that determine signal recognition at chemoreceptors is limited. Chemoreceptor McpA of Bacillus velezensis SQR9 has been shown to mediate chemotaxis to a broad range of different ligands. Here we show that its ligand binding domain binds directly 13 chemoattractants. We provide support that organic acids and amino acids bind to the membrane-distal and membrane-proximal module of the dCache domain, respectively, whereas binding of sugars/sugar alcohols occurred at both modules. Structural biology studies combined with site-directed mutagenesis experiments have permitted to identify 10 amino acid residues that play key roles in the recognition of multiple ligands. Residues in membrane-distal and membrane-proximal regions were central for sensing organic acids and amimo acids, respectively, whereas all residues participated in sugars/sugar alcohol sensing. Most characterized chemoreceptors possess a narrow and well-defined ligand spectrum. We propose here a sensing mechanism involving both dCache modules that allows the integration of very diverse signals by a single chemoreceptor.

Elemental mercury (Hg0) is a highly hazardous pollutant of coal combustion. The low-temperature SCR catalyst of MnOx/TiO2 can efficiently remove Hg0 in coal-burning flue gas. Considering its sulfur sensitivity, the effect of SO3 on the catalytic efficiency of MnOx/TiO2 and Fe modified MnOx/TiO2 for Hg0 removal was investigated comprehensively for the first time. Characterizations of Hg-TPD and XPS were conducted to explore the catalytic mechanisms of Hg0 removal processes under different conditions. Hg0 removal efficiency of MnOx/TiO2 was inhibited irreversibly from 92% to approximately 60% with the addition of 50 ppm SO3 at 150 ℃, which resulted from the transformation of Mn4+ and chemisorbed oxygen to MnSO4. The existence of H2O would intensify the inhibitory effect. The inhibition almost disappeared and even converted to promotion as the temperature increased to 250 ℃ and above. Fe modification on MnOx/TiO2 improved the Hg0 removal performance in the presence of SO3. The addition of SO3 caused only a slight inhibition of 1.9% on Hg0 removal efficiency of Fe modified MnOx/TiO2 in simulated coal-fired flue gas, and the efficiency maintained good stability during a 12 h experimental period. This work would be conducive to the future application of MnOx/TiO2 for synergistic Hg0 removal.

A kinetic approach was adopted to analyze the reaction mechanism of elemental mercury (Hg0) oxidation by HCl over three Mn-based low-temperature SCR catalysts, MnOx/TiO2, Fe-MnOx/TiO2 and CeMnO3. Experimental results validated that Hg0 oxidation efficiencies of the catalysts were promoted by HCl at different temperatures. The kinetic models for the heterogeneous Hg0 oxidation were established and verified based on the experimental data. The verification results demonstrated that Hg0 oxidation over the Mn-based catalysts follows Langmuir-Hinshelwood mechanism. The kinetic parameters of reaction rate constant and HCl adsorption constant were calculated from the model fitting equations. The reaction rate constant was raised with the increase of temperature, while the HCl adsorption constant presented the opposite trend. The Mn-based catalysts with the reaction rate constant of 84.17–335.77 s−1 showed the advantage over some other catalysts such as commercial V2O5-(WO3)/TiO2 and CeO2/TiO2. The kinetic parameters were further improved in the presence of O2. The apparent activation energy for Hg0 oxidation over the catalysts that was derived from the kinetic parameters was 4.13–12.53 kJ/mol, which was much lower than that of the other approaches. The advantageous kinetic parameters and apparent activation energy were favorable for the Mn-based catalysts to act as low-temperature SCR catalyst for synergistic Hg0 removal. The kinetic study results were of fundamental significance for designing the reactor according to the known flue gas conditions, used catalyst and required Hg0 oxidation efficiency.

Data of 239+240Pu activities and 240Pu/239Pu atom ratios in surface and core sediments of the China Sea and adjacent waters were collected. We examine a dataset of 239+240Pu activities and 240Pu/239Pu ratios determined from surface sediments at 516 sites and 84 core sediment mainly across the China Sea and adjacent waters. For the first time the spatial distributions of the 239+240Pu activities, the 240Pu/239Pu ratios and the Pacific Proving Ground (PPG) fraction in the China Sea and adjacent waters are fully presented at the same time. Four types of typical 239+240Pu distribution with depth are commonly summarized: non-peak, pseudo single peak, single peak and multi peaks, which are based on the comprehensive analysis of the vertical distribution of 239+240Pu in 84 sediment cores that had been studied in the China Sea and adjacent waters. Their occurrence probability are ∼15%, ∼4%, ∼67% and ∼11%, respectively. This is the dominant Pu source in seawater which was transported by the North Equatorial Current and Kuroshio Current and its extension into the China Sea and adjacent waters first from east to west, then from south to north. A sea area to the northeast of Taiwan Island and the Okinawa Trough, shows high 239+240Pu activities and 240Pu/239Pu atom ratios spatial distribution trends, which are related to the intrusion of the Kuroshio Current carrying 239+240Pu from the PPG nuclear weapon tests. The used two end-member mixing model suggests that global fallout and PPG close-in fallout are the main sources of Pu in most of the investigate areas. As the 240Pu/239Pu of global fallout is relatively constant, the change of 240Pu/239Pu ratios in surface sediments of the China Sea and adjacent waters are mainly controlled by the PPG close-in fallout input.

Ternary hydrides are ideal candidates for high-temperature superconductivity. However, their electronic properties correlate strongly with the charge transfer between their consistent elements. In this work we propose nine Na-B-H compounds, which combines charge modulation between Na and B/H atoms with pressure, with unusual structural motifs and interesting electronic properties. In the metallic Pmma NaBH3, with both ionic and covalent frameworks, formed by H atoms bonded to Na/B atoms, a low-frequency phonon dominated superconductivity is predicted with a Tc of 86.8 K, distinct from the high-frequency H-derived superconductivity associated with covalent H-based skeletons or H cages/sheets in superhydrides. Furthermore, in nonmetallic NaBHn (n=1,2, and 6) and R−3m NaBH3, the B atom exhibits an sp3-hybridized feature analogous to the C atom, resulting in the formation of several alkanelike B-H motifs, such as a graphanelike layer and an ethane-shaped molecule. Our work presents an important step toward the understanding of metal borohydrides.

The migration of radionuclides is a critical threat to the soil and groundwater environment. This study investigates highly radiological toxic 239+240Pu in 647 surface soils and 66 soil cores in China. First, the spatial distributions of 239+240Pu activities and 240Pu/239Pu ratios are presented in Chinese surface soils. Second, four different types of vertical distribution of 239+240Pu, namely 45.4%, 40.9%, 9.1% and 4.5% of Chinese soil cores proportions are integrated using statistical analysis. Furthermore, different soil types are accompanied by different 239+240Pu vertical distributions, which relate closely to the 239+240Pu migration. Finally, based on the Convection Dispersion Equation (CDE) model, the present work find that the apparent convection velocities of 239+240Pu are ranging from 0.00032 ± 0.00031 cm a−1 to 0.473 ± 0.083 cm a−1. As shown by the four typical vertical activity distribution of 239+240Pu in soil cores, the deepened activity maximum value position of 239+240Pu implies a fast migration rate or apparent convection velocity. This study, for the first time, suggests a significant linear correlation (R2 = 0.847) between the depth of 239+240Pu maximum value (cm) and the apparent convection velocity (v, cm a−1). We hypothesize that v usually does not exceed 0.5 cm a−1 in the CDE model. A significant linear correlation is also identified between apparent dispersion coefficient (D, cm2 a−1) and v2 in Chinese soil cores from the CDE model. It will provide an important reference for harmful heavy metal migration research in the future.

Overstorey biodiversity is known to drive multiple ecosystem functions in mature forests. However, the role of understorey biodiversity in regulating the soil microbiome and ecosystem multiservices of these ecosystems is virtually unknown. Here, we collected vegetation and soil data from mature plantation Mediterranean pine forests (100 years old) with different combinations of tree and understorey plant species to explore the contri-bution of overstorey and understorey biodiversity for explaining soil microbiomes and ecosystem multiservices. We found that while overstorey diversity is important for supporting soil-borne pathogen control, forest understorey biodiversity is critical for explaining soil nutrient availability, tree production, and soil-plant mutualistic relationships. Our results highlight the importance of understorey biodiversity for maintaining ecosystem multiservices in mature forests, which should be considered in forest management programs.

An optimal temperature is crucial for a broad range of applications, from chemical transformations, electronics, and human comfort, to energy production and our whole planet. Photochemical molecular thermal energy storage systems coupled with phase change behavior (MOST-PCMs) offer unique opportunities to capture energy and regulate temperature. Here, we demonstrate how a series of visible-light-responsive azopyrazoles couple MOST and PCMs to provide energy capture and release below 0 °C. The system is charged by blue light at -1 °C, and discharges energy in the form of heat under green light irradiation. High energy density (0.25 MJ kg-1) is realized through co-harvesting visible-light energy and thermal energy from the environment through phase transitions. Coatings on glass with photo-controlled transparency are prepared as a demonstration of thermal regulation. The temperature difference between the coatings and the ice cold surroundings is up to 22.7 °C during the discharging process. This study illustrates molecular design principles that pave the way for MOST-PCMs that can store natural sunlight energy and ambient heat over a wide temperature range.

The soft hybrid organic–inorganic structure of two-dimensional layered perovskites (2DLPs) enables broadband emission at room temperature from a single material, which makes 2DLPs promising sources for solid-state white lighting, yet with low efficiency. The underlying photophysics involves self-trapping of excitons favored by distortions of the inorganic lattice and coupling to phonons, where the mechanism is still under debate. 2DLPs with different organic moieties and emission ranging from self-trapped exciton (STE)-dominated white light to blue band-edge photoluminescence are investigated. Detailed insights into the directional symmetries of phonon modes are gained using angle-resolved polarized Raman spectroscopy and are correlated to the temperature-dependence of the STE emission. It is demonstrated that weak STE bands at low-temperature are linked to in-plane phonons, and efficient room-temperature STE emission to more complex coupling to several phonon modes with out-of-plane components. Thereby, a unique view is provided into the lattice deformations and recombination dynamics that are key to designing more efficient materials.

Coastal zones are active reactors of continental material including that transported by rivers via a series of microbiota-mediated reactions. Nevertheless, current knowledge of the ecology and functioning of the microbiota in coastal areas affected by large riverine inputs remains insufficient on a global scale. Here, an investigation on sediment microbial composition, including taxonomy and metabolic network, as well as their relationship with major benthic reaction substrates, namely carbon, nitrogen, sulphur and phosphorus, was conducted in the continental shelf affected by the spread of the Changjiang River plume. Surface sediment samples (48 samples) were collected during March 2018, obtaining a mean Operational Taxonomic Units (OTUs) number of 3 341. Proteobacteria, Acidobacteria and Actinobacteria were abundant phyla in the studied sediments. Bray-Curtis distance analysis classified the 48 samples into 4 clusters (MG1 to MG4) at the phylum-level. MG1 and MG2 are found near the river mouth, receiving substantial land-derived particles from the Changjiang River runoff. Particle-attached microbes may be settled in these regions and influenced the observed sediment microbial diversity and biomass, e.g., increased Crenarchaeota relative abundance. The relative enrichment of these two groups in heterotrophic microbes further suggests a reliance of benthic microbiota on substrates with terrestrial origin, particularly specialized on processing sulphur-rich substrates. Regions MG3 and MG4 are located in the outer margin of the area affected by the Changjiang River plume, mainly fed by settling pelagic particles from phytoplankton. Compared to MG1 and MG2, a significant increase in the abundance of Thaumarcheota (phylumlevel) and Nitrosopumilus (genus-level) was found in MG3, suggesting nitrogen-related transformations as the key reactions to sustain microbial metabolism in this region. Coupled with the identified variations in the taxonomic composition, significant d

Novel structural building blocks in compounds could induce interesting physical and chemical properties. Although phosphorus tends to form very different motifs, the existence of lone pair electrons has always prevented the formation of graphenelike structures. Here, the application of first-principles swarm structural calculations has allowed us to predict the stability of pressure-induced hexagonal LaP2H2 containing graphenelike phosphorus, which derives from the trigonal bipyramid configuration of P atoms regulated by symmetric hydrogen bonds. LaP2 in LaP2H2 has the same configuration as MgB2, and P and H atoms form a three-dimensional framework as H3S. Interestingly, LaP2H2 shows a superconductivity dominated by the graphenelike phosphorus layer and its coupling with La atoms. On the other hand, LaP2H2 is not only superconducting at a lower pressure than the H-rich LaPH6, but it also shows a superconducting transition temperature three times higher. Our work provides an example which extends the landscape of conventional superconductors at lower pressures.

Soil fungi are fundamental to plant productivity, yet their influence on the temporal stability of global terrestrial ecosystems, and their capacity to buffer plant productivity against extreme drought events, remain uncertain. Here we combined three independent global field surveys of soil fungi with a satellite-derived temporal assessment of plant productivity, and report that phylotype richness within particular fungal functional groups drives the stability of terrestrial ecosystems. The richness of fungal decomposers was consistently and positively associated with ecosystem stability worldwide, while the opposite pattern was found for the richness of fungal plant pathogens, particularly in grasslands. We further demonstrated that the richness of soil decomposers was consistently positively linked with higher resistance of plant productivity in response to extreme drought events, while that of fungal plant pathogens showed a general negative relationship with plant productivity resilience/resistance patterns. Together, our work provides evidence supporting the critical role of soil fungal diversity to secure stable plant production over time in global ecosystems, and to buffer against extreme climate events.

Aim Fresh carbon (C) inputs to the soil can have important consequences for the decomposition rates of soil organic matter (priming effect), thereby impacting the delicate global C balance at the soil-atmosphere interface. Yet, the environmental factors that control soil priming effect intensity remain poorly understood at a global scale. Location Global. Time period 1980-2020. Major taxa studied Soil priming effect intensity. Methods We conducted a global dataset of CO2 effluxes in 711 pairwise soils with C-13 or C-14 simple C sources inputs and without C inputs from incubation experiments in which isotope-labelled C was used to quantify fresh C-induced rather than exudate-induced priming. Results Soil priming effect intensity is predominantly positive. Soil texture and C content were identified as the most important factors associated with priming effects, with sandy soils from tropical and mid-latitudes supporting the highest soil priming effect intensity, and soils with greater C content and fine textures from high latitudes maintaining the lowest soil priming effects. The negative association between C content and soil priming effect intensity was also indirectly driven by changing mean annual temperature, net primary productivity, and fungi : bacteria ratio. Using this information, we generated a global map of soil priming effect intensity, and found that the priming was lower at high latitudes and higher at lower latitudes. Main conclusions Global patterns of soil priming effect intensity can be predicted using environmental data, with soil texture and C content playing a predominant role in explaining in priming effects. These effects were also indirectly driven by climate, vegetation and soil microbial properties. We present the first global atlas of soil priming effect intensity and advance our knowledge on the potential mechanisms underlying soil priming effect intensity, which are integral to improving the climate change and soil C dynamics components of

Although selenium (Se) is an essential microelement for humans and animals, it is a potentially toxic element due to its bioaccumulation potential. In this study, Se fertilizer was supplied in a greenhouse vegetable (cucumber) plantation using an innovative system consisting of nanobubbles (NB_Se) and compared to that under conventional conditions of fertigation (C_Se) with six doses. The results revealed that NB_Se significantly reduced soil Se accumulation (38%−144%) and increased cucumber Se content compared with the C_Se treatments at the same Se dose. NB_Se significantly lowered the soil bacterial diversity, with an initial increase and then decrease with the Se doses. Bacterial associations and potential keystone taxa also differed between the NB_Se and C_Se. The greater abundance of oxidizing bacteria (indicated by the function composition of bacterial community) and the improved soil redox environment created by NBs sustained more available Se for plants, leading to a reduction in soil Se residual and an increase in the plant Se content. Our results highlight the feasibility and efficiency of NB_Se and demonstrate the important implications of Se for the maintenance of soil health and sustainability.

Rhizosphere hypoxia severely inhibited plant growth, reducing the crop yield and water use efficiency (WUE) in greenhouse crops. Irrigation using nanobubbles (NBs) has been an efficient method to increase crop yield and WUE by ameliorating hypoxic conditions and promoting plant growth. However, the potential effects and mechanisms of different oxygen concentrations in water enriched in nanobubbles (NBW) remain unclear. Herein, this study examined the influence of different total oxygen concentrations (TOCs, ranged between 160 and 280 mg L) on tomato agronomic performance, soil fertility, and the bacterial community after a two-season of NBW irrigation. The results indicated that the tomato yield, WUE, soluble sugar, and vitamin C were significantly improved by NBs, showing the trends of rising to decrease with the corresponding oxygen concentration in irrigation water. The total C (TC), organic matter (OM), available N (AN) and K (AK) in soil tended to increase and then decrease with TOC in irrigation water. NB obtained the highest soil OM and AN values, and NB obtained the highest TC and AK values. The soil bacterial community composition gradually differentiated with increasing oxygen concentration. There were significant differences in relative abundances of Proteobacteria and Nitrospirae across the six oxygen levels. The keystones in the co-occurrence network were dependent on oxygen levels. FAPROTAX results revealed that bacterial functions of methanol oxidation, N fixation, aerobic chemoheterotrophy, and cellulolysis were more abundant in NB treated soils, consequently resulting in better crop yield, WUE, and soil fertility. Overall, the increased abundance of taxa participating in soil nutrient turnover contributed to improved soil fertility and crop agronomic performance. Our findings provided a significant opportunity to advance the understanding of oxygen threshold during aerated irrigation, with implications for green and efficient agricultural production

Excessive application of nitrogen fertilizers has inevitably resultedin environmental problems. The symbiotic nitrogen fixation (SNF) that occurs in the root nodules of leguminous plants provides asustainable source of reduced nitrogen in agricultural ecosystems. More than 200 genes have been reported to regulate SNF, including rhizobial infection, nodule organogenesis and senescence (Royet al., 2020). Mature nodules consist mainly of twocell types: infected cells (IC) that contain nitrogen-fixing bac-teroids and uninfected cells (UC) that mediate active metabolismand nutrient transport. Although it is well known that SNFrequires functional specialization, the specific genes responsiblefor transcriptional regulation and carbon/nitrogen metabolismand transport in IC and UC remain largely unexplored.Single-cell transcriptomics has emerged as a powerful tech-nique for investigating spatiotemporal patterns of gene expression.

Achieving a compound with interesting multiple coexisting states, such as electride, metallicity, and superconductivity, is of great interest in basic research and practical application. Pressure has become an effective way to realize high-temperature superconductivity in hydrides, whereas most electrides are semiconducting or insulating at high pressure. Here, we have applied swarm-intelligence structural search to identify a hitherto unknown C2/m Li10Se electride that is superconducting at high pressure. More interestingly, Li10Se is estimated to exhibit the highest Tc value of 16 K at 50 GPa, which is the lowest pressure among Li-based chalcogen electrides. This superconducting transition is dominated by Se-related low frequency vibration modes. The increasing electronic occupation of the Se 4d orbital and the decreasing amount of interstitial anion electrons with pressure heighten their coupling with low-frequency phonons, which is responsible for the enhancement of the Tc value. The finding of Li-based chalcogen superconducting electrides provides a reference for the realization of other superconducting electrides at lower pressures.

Estimating 210Pb sources/sinks is significant for understanding the transport processes and chronology of sediment in coastal seas. Although submarine groundwater discharge (SGD) has been recognized as an important pathway for the transport of terrestrial chemical components, the 210Pb source in coastal seas from SGD is generally ignored. In the present work, we built the 210Pb budget by analyzing the 210Pb activity concentrations in submarine groundwater (i.e., coastal well water and pore water), river water, and seawater in a typical aquaculture bay along the Chinese coast in the Beibu Gulf (Qinzhou Bay). The results showed that the 210Pb activity concentrations (Bq/m3) in well water, porewater, seawater and river water were 6.0 ± 3.6 (n = 13), 3.8 ± 0.4 (n = 2), 1.2 ± 0.3 (n = 4), and 1.9 ± 0.6 (n = 3), respectively. The SGD-derived 210Pb flux was calculated to be (3.3 ± 0.4) × 1010 Bq/yr (approximately 1.4 times the river input flux), which accounted for ∼18% of the total 210Pb sources in Qinzhou Bay. Although most of the 210Pb (>66%) would be buried into the sediment of this coastal bay, SGD-discharged dissolved 210Pb can account for approximately half of the ocean mixing, which is the second most important 210Pb sink in Qinzhou Bay. Therefore, based on these estimates, we have shown that the 210Pb input from SGD can be an important source at the coastal sea scale and needs to be accounted for in coastal sea areas

Global reanalysis products have become essential tools employed towards the understanding of past climates, which are extensively employed by the wind energy industry to assess and develop wind resources. In this study, the terrestrial near-surface wind speed (NSWS) in the 40 year global reanalysis dataset released by China Meteorological Administration (CRA-40) was employed and compared with four state-of-the-art global reanalysis products, namely the European Centre for Medium-Range Weather Forecasts reanalysis version 5 (ERA5), National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis (NCEP1), National Centers for Environmental Prediction-Department of Energy reanalysis (NCEP2), and the Japanese 55 year reanalysis (JRA55). Large discrepancies were revealed among the reanalysis products in NSWSs across China. CRA-40 captures the climatology, seasonal, interannual, and monthly changes, as well as the terrestrial stilling compared with the recent observed increase. In contrast, NCEP1 and NCEP2 fail to reproduce the climatology and monthly changes in the observed NSWSs. Although JRA55 captures the terrestrial stilling in observations, it underestimates the mean value of NSWS. Therefore, CRA-40 provides the best agreement with stronger and more significant correlations against the observations when compared to other reanalysis products, and reproduces the observed multi-decadal variability. Thus, CRA-40 is the optimal choice to investigate NSWS with high spatial and temporal resolution across China, with a wide array of socioeconomic and environmental impacts.

Achieving superconductivity in hydrides at lower pressures is a long-standing scientific challenge. Here, we propose that reducing their effective dimensionality might be a possible route to achieve this goal. First-principles structural search calculations identify several two-dimensional transition metal hydrides (TMHs) with phonon-mediated superconductivity. Among them, the two CuH2 phases with P−3m1 and P−6m2 symmetries are predicted to have the highest Tc values up to 44.4 and 47.8 K, comparable to the well-known MgB2 superconductor. Their superconductivity mainly originates from the coupling of Cu3dxz/dyz and H−1s electrons with in-plane H-vibrational phonons. Interestingly, both CuH2 structures show a unique superconducting energy gap by solving the anisotropic Eliashberg equations. Furthermore, the superconductivity of TMHs is closely related to the polarity of the TM-H bond. Our paper paves the way for finding hydride superconductors in low-dimensional materials.

Iron-based (Fe-based) cermets with silicon carbide particles (SiCP) as abrasive were prepared by vacuum hot pressing sintering. The influence of SiCP content on the microstructure and grinding performance of Fe-based cermets was studied. The microstructure, mechanical properties, and grinding performance of the prepared cermets were tested and analyzed to explore the grinding mechanism of Fe-SiC cermets. It was shown that the grinding mechanism changed due to the reduction of SiCP content. And the grinding behavior was related to the bonding force between SiCP and matrix. Through experiments and finite element analysis, the source/distribution of grinding heat and heat flow were verified, and the mechanism of material removal was revealed. The results showed that with the decrease of SiCP content, the grinding behavior of cermet changed from cutting and plowing to friction.