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Graded polycrystalline copper materials have been expected in the field of scientific research and engineering in recent years because the core of the material has enough toughness and a sufficient surface strength. However, the plastic deformation mechanism, gradient grain generation mechanism and material strengthening principle of polycrystalline copper are still not well understood. Therefore, it is urgent to further analyze the plastic deformation of polycrystalline copper. In this study, the micron scale plastic deformation behavior of polycrystalline copper is simulated based on the crystal plasticity finite element method. The simulation analysis is carried out from the aspects of grain size, grain shape, crystal orientation type and quantity, loading mode and so on. The effects of the above parameters on the Mises stress nephogram and stress-strain curve of polycrystalline copper were analyzed. At the end of the article, the EBSD orientation distribution information of graded polycrystalline copper grains obtained in the cutting process is analyzed comprehensively and the formation mechanism of graded polycrystalline copper is explained by combining the simulation results.

Background: Colorectal cancer (CRC) is a prevalent malignancy of the digestive tract. A new prognostic scoring model for colon adenocarcinoma (COAD) is developed in this study based on the genes involved in tumor cell-mediated killing of T cells (GSTTKs), accurately stratifying COAD patients, thus improving the current status of personalized treatment. Method: The GEO and TCGA databases served as the sources of the data for the COAD cohort. This study identified GSTTKs-related genes in COAD through single-factor Cox analysis. These genes were used to categorize COAD patients into several subtypes via unsupervised clustering analysis. The biological pathways and tumor microenvironments of different subgroups were compared. We performed intersection analysis between different subtypes to obtain intersection genes. Single-factor Cox regression analysis and Lasso-Cox analysis were conducted to establish clinical prognostic models. Two methods are used to assess the accuracy of model predictions: ROC and Kaplan-Meier analysis. Next, the prediction model was further validated in the validation cohort. Differential immune cell infiltration between various risk categories was identified via single sample gene set enrichment analysis (ssGSEA). The COAD model's gene expression was validated via single-cell data analysis and experiments. Result: We established two distinct GSTTKs-related subtypes. Biological processes and immune cell tumor invasion differed significantly between various subtypes. Clinical prognostic models were created using five GSTTKs-related genes. The model's risk score independently served as a prognostic factor. COAD patients were classified as low- or high-risk depending on their risk scores. Patients in the low-risk category recorded a greater chance of surviving. The outcomes from the validation cohort match those from the training set. Risk scores and several tumor-infiltrating immune cells were strongly correlated, according to ssGSEA. Single-cell data illustrated that the model's genes were linked to several immune cells. The experimental results demonstrated a significant increase in the expression of HOXC6 in colon cancer tissue. Conclusion: Our research findings established a new gene signature for COAD. This gene signature helps to accurately stratify the risk of COAD patients and improve the current status of individualized care.

Abstract Productivity benefits from diversity can arise when compatible pathogen hosts are buffered by unrelated neighbors, diluting pathogen impacts. However, the generality of pathogen dilution has been controversial and rarely tested within biodiversity manipulations. Here, we test whether soil pathogen dilution generates diversity- productivity relationships using a field biodiversity-manipulation experiment, greenhouse assays, and feedback modeling. We find that the accumulation of specialist pathogens in monocultures decreases host plant yields and that pathogen dilution predicts plant productivity gains derived from diversity. Pathogen specialization predicts the strength of the negative feedback between plant species in greenhouse assays. These feedbacks significantly predict the overyielding measured in the field the following year. This relationship strengthens when accounting for the expected dilution of pathogens in mixtures. Using a feedback model, we corroborate that pathogen dilution drives overyielding. Combined empirical and theoretical evidence indicate that specialist pathogen dilution generates overyielding and suggests that the risk of losing productivity benefits from diversity may be highest where environmental change decouples plant-microbe interactions.

Abstract The intensification of estrogen non-point source pollution has drawn global attention due to their contribution to ecological environment problems worldwide, and it is critical to develop effective, economic and eco-friendly methods for reducing estrogens pollution. To address the agglomeration and oxidation of nano zero-valent iron (nZVI), biochar-nanoscale zero-valent iron composite (nZVI-biochar) could be a feasible choice for estrogens removal. This study summarized biochar and nZVI-biochar preparation, characterization, and unusual applications for estrone (E1), 17β-estradiol (E2), and estriol (E3) removal. The properties of biochar and nZVI-biochar in characterization, effects of influencing factors on the removal efficiency, adsorption kinetics, isotherm and thermodynamics were investigated. The experiment results showed that nZVI-biochar exhibited the superior removal performance for estrogens pollutants compared to biochar. Based on the quasi-second-order model, estrogens adsorption kinetics were observed, which supported the mechanism that chemical and physical adsorption existed simultaneously on estrogens removal. The adsorption isotherm of estrogens could be well presented by the Freundlich model and thermodynamics studies explained that nZVI-biochar could spontaneously remove estrogens pollutants and the main mechanisms involved π-π interaction, hydrophobic interaction, hydrogen bonding and degradation through ring rupture. The products analyzed by GC–MS showed that estrogens degradation was primarily attributed to the benzene ring broken, and Fe3+ promoted the production of free radicals, which further proved that nZVI-biochar had the excellent adsorption performances. Generally, nZVI-biochar could be employed as a potential material for removing estrogens from wastewater. Graphical Abstract

There are studies on titanium gypsum (TG) as a cement retarder, cementing material, or the production of lightweight wall materials and roadbed materials, but the application of TG is still limited, the utilization of TG is in the stage of exploration. This work studied the possibility of recycling TG as raw materials for the preparation of cement-based (Sulphate Aluminate Cement and Ordinary Portland Cement) self-leveling mortars. The effects of TG on mechanical strength, fluidity, shrinkage, and wear resistance were carried out. With the help of XRD, TG-DTG, and SEM, the microstructural characteristics were investigated to determine the mechanism of TG. It was concluded that the 1 d compressive and flexural strength reached 9.6 MPa and 3.5 MPa, respectively, and the 28 d compressive and flexural strength reached 4.3 MPa and 17.9 MPa, respectively, when the mass ratio of Sulphate Aluminate Cement (SAC) and Ordinary Portland Cement (OPC) was 7:3, the TG content was 45 %. TG could significantly improve the shrinkage of the mortars to 0.10 %, which was far better than the standard requirements of 0.15 %, but reduce the wear resistance to some extent. The primary component of calcium sulfate dihydrate (CaSO4·2H2O) in TG can further react with the aluminum phase in cement to grow more ettringite, which can make the microstructure denser, thereby improving the strength and the deformation of the cement-based self-leveling mortars.

Abstract Research suggests that microbiomes play a major role in structuring plant communities and influencing ecosystem processes, however, the relative roles and strength of change of microbial components have not been identified. We measured the response of fungal, arbuscular mycorrhizal fungal (AMF), bacteria, and oomycete composition 4 months after planting of field plots that varied in plant composition and diversity. Plots were planted using 18 prairie plant species from three plant families (Poaceae, Fabaceae, and Asteraceae) in monoculture, 2, 3, or 6 species richness mixtures and either species within multiple families or one family. Soil cores were collected and homogenized per plot and DNA were extracted from soil and roots of each plot. We found that all microbial groups responded to the planting design, indicating rapid microbiome response to plant composition. Fungal pathogen communities were strongly affected by plant diversity. We identified OTUs from genera of putatively pathogenic fungi that increased with plant family, indicating likely pathogen specificity. Bacteria were strongly differentiated by plant family in roots but not soil. Fungal pathogen diversity increased with planted species richness, while oomycete diversity, as well as bacterial diversity in roots, decreased. AMF differentiation in roots was detected with individual plant species, but not plant family or richness. Fungal saprotroph composition differentiated between plant family composition in plots, providing evidence for decomposer home-field advantage. The observed patterns are consistent with rapid microbiome differentiation with plant composition, which could generate rapid feedbacks on plant growth in the field, thereby potentially influencing plant community structure, and influence ecosystem processes. These findings highlight the importance of native microbial inoculation in restoration.

Abstract Background Arbuscular mycorrhizal fungi (AMF) are key soil organisms and their extensive hyphae create a unique hyphosphere associated with microbes actively involved in N cycling. However, the underlying mechanisms how AMF and hyphae-associated microbes may cooperate to influence N2O emissions from “hot spot” residue patches remain unclear. Here we explored the key microbes in the hyphosphere involved in N2O production and consumption using amplicon and shotgun metagenomic sequencing. Chemotaxis, growth and N2O emissions of isolated N2O-reducing bacteria in response to hyphal exudates were tested using in vitro cultures and inoculation experiments. Results AMF hyphae reduced denitrification-derived N2O emission (max. 63%) in C- and N-rich residue patches. AMF consistently enhanced the abundance and expression of clade I nosZ gene, and inconsistently increased that of nirS and nirK genes. The reduction of N2O emissions in the hyphosphere was linked to N2O-reducing Pseudomonas specifically enriched by AMF, concurring with the increase in the relative abundance of the key genes involved in bacterial citrate cycle. Phenotypic characterization of the isolated complete denitrifying P. fluorescens strain JL1 (possessing clade I nosZ) indicated that the decline of net N2O emission was a result of upregulated nosZ expression in P. fluorescens following hyphal exudation (e.g. carboxylates). These findings were further validated by re-inoculating sterilized residue patches with P. fluorescens and by an 11-year-long field experiment showing significant positive correlation between hyphal length density with the abundance of clade I nosZ gene. Conclusions The cooperation between AMF and the N2O-reducing Pseudomonas residing on hyphae significantly reduce N2O emissions in the microsites. Carboxylates exuded by hyphae act as attractants in recruiting P. fluorescens and also as stimulants triggering nosZ gene expression. Our discovery indicates that reinforcing synergies between AMF and hyphosphere microbiome may provide unexplored opportunities to stimulate N2O consumption in nutrient-enriched microsites, and consequently reduce N2O emissions from soils. This knowledge opens novel avenues to exploit cross-kingdom microbial interactions for sustainable agriculture and for climate change mitigation. Video Abstract

[Objective] The ecological carrying capacity of water resources in the lower reaches of the Yellow River basin was evaluated in order to provide a theoretical basis for regional water resource management and planning. [Methods] The spatial and temporal distribution characteristics and driving mechanism of the ecological footprint of water resources in the lower reaches of the Yellow River basin from 2007 to 2020 were calculated and analyzed using the theory of ecological footprint of water resources and the logarithmic mean Divisia index method (LMDI), The grey forecasting model GM(1,1) was applied to predict the change trend of the ecological footprint of water resources from 2021 to 2030. [Results] The ecological footprint of water resources in the lower reaches of the Yellow River over the study years was much greater than the ecological carrying capacity, and the ecological deficit of water resources was serious. Both the ecological footprint of water resources and the ecological deficit showed a fluctuating and decreasing trend over years, and the efficiency of water use was gradually improving. Agricultural water consumption was the largest factor accounting for the ecological footprint of water resources. The Yellow River Delta was the area with the greatest ecological pressure on water resources in the lower reaches of the Yellow River basin. Zibo, Jinan, Zhengzhou, and Tai’an City had relatively little ecological pressure. The economic effect had a major positive role in the change of the ecological footprint of water resources in the lower reaches of the Yellow River basin, and the technical effect had a major negative role. The forecast results indicated that the ecological deficit of water resources per capita in the lower reaches of the Yellow River basin would decrease from 0.387 to 0.359 hm2/person from 2021 to 2030. [Conclusion] The water use efficiency in the lower reaches of the Yellow River basin has gradually increased over time, and the ecological pressure on water resources has been relieved to a certain extent under the comprehensive effects of rapid development of productivity and optimization and adjustment of water-using structures. However, the sustainable utilization of water resources in the future is still under very serious pressure due to the large deficit in the ecological base of water resources in this region. It is therefore urgent to further strengthen the overall management of water resources in order to help the lower reaches of the Yellow River basin achieve high-quality sustainable development.

In this paper, an extended three-dimensional (3D) model of the Yellow River Estuary (YRE) is established. It is based on a Delft 3D shallow-water high-resolution hydrodynamic model. The model is calibrated and verified by field observation data, which ensures its stability and accuracy, and provides a better simulation of the river plume in the estuary under different flow inputs. Since 2009, the spring flow pulse of the Yellow River can be divided into four types. The strong flow pulse is more conducive to the extension of the low salinity zone (LSZ). Doubling the peak discharge of pulse flow increases the LSZ area by 60%. The retardation time of salinity change in response to the flow pulse in estuary waters is weakly affected by the flow pulse intensity. The difference in shear front between the spring tide and the neap tide is the main dynamic mechanism contributing to the different retardation times. The average retardation time is 73 h during the spring tide and 55 h during the neap tide. In order to reduce the estuary salinity, it is suggested that the optimal time for the peak value of flow pulse in the river mouth is during the neap tide. HIGHLIGHTS An extended three-dimensional (3D) model of the Yellow River is established based on a Delft 3D shallow-water high-resolution hydrodynamic model.; The study focused on the change process of salinity distribution in the Yellow River Estuary under different discharge conditions.; The retardation time of salinity change in response to the flow pulse in estuary waters is affected by the flow pulse intensity.;

Signals generated by dust impacting spacecraft can be detected by electric field instruments. These signals have been simulated by numerous models. However, few models can accurately characterize the expansion of the plasma cloud generated by dust impact. The COMSOL model presented in this paper provides a way to understand the expansion properties of ions and electrons. The model can also be used to analyze the various expected waveforms of dust impact signals as a function of different parameters, such as the spacecraft voltage and the ambient plasma temperature. The results show that close to 50% of ions and electrons in the impact plasma cloud are collected by spacecraft at weak spacecraft potentials and that a fraction of the ions is still collected rather than all of them streaming away from the impact location at V _SC > 0 V. The model also confirms that in the expanding plasma cloud, ions are in the form of plumes, while electrons diffuse in an isotropic manner.

Nanoscale zero-valent iron-supported biochar pellets (nZVI)-(BP) were synthesized via liquid-phase reduction and applied to estrogen removal, including estrone (E1), 17β-estradiol (E2), and estriol (E3). The performance of nZVI-BP, with respect to its characterization, removal kinetics, and isotherms, was investigated. The results showed that the adsorption equilibrium was reached within 10 min of exposure. The adsorption capacity of estrogen decreased with increasing solute pH and nZVI-BP dosage. The adsorptivity increased with increasing initial estrogen concentration. The estrogen behavior followed a pseudo-second-order kinetic model. The adsorption data of different initial estrogen concentrations fitted to Freundlich adsorption isotherms. In addition, a preliminary discussion of the adsorption mechanism of nZVI-BP for estrogens was provided. HIGHLIGHTS BP-supported nZVI was prepared to apply for removing estrogens.; The proper reaction conditions were recommended for estrogen removal.; The mechanisms of estrogen removal by BP-supported nZVI were probed.;

Glass fibers are widely used in cement-based precast products, given the reinforcing requirements for toughness and strength. However, inferior alkali resistance hinders the effectiveness of glass fibers in reinforcing cement-based materials. In this paper, nanoparticle coatings were applied on the surface of alkali-resistant glass fiber (ARGF) as a protective layer via the in situ chemical reaction of oleic acid (OA) and potassium permanganate (PP). The morphology and constituents of the as-prepared ARGFs were examined using scanning electron microscopy (SEM) and obtaining X-ray photoelectron spectroscopy (XPS) measurements. Mass loss and strength retention were investigated to characterize alkali resistance of modified ARGFs. Results showed that ARGFs could be optimally coated by a layer of MnO2-based nanoparticles consisting of approximately 70% MnO2, 18% MnO, and 12% MnSiO3, when modified with an optimum OA to PP ratio of 10 for 24 h. The dissolution of ARGFs matrix in 4% and 10% NaOH solutions were distinctly delayed to 28 d, as a consequence of the introduction of the MnO2-based nanoparticle layer, compared with nontreated ARGF occurring at 3 d in 4% NaOH solution. For the optimally modified ARGFs, the mass loss was controlled to 1.76% and 2.91% after 90 d of corrosion in 4% and 10% NaOH solutions, and the retention of tensile strength was increased by approximately 25%. With respect to the increment in alkali-resistant performance, the modified ARGFs can be promising candidates for wide applications in alkaline cement-based products.

Beyond interacting with neighboring plants, crop performance is affected by the microbiome that includes pathogens and mutualists. While the importance of plant–plant interactions in explaining overyielding in intercropping is well known, the role of the microbiome, in particular how the presence of microbes from heterospecific crop species inhibit pathogens of the focal plants in affecting yield remains hardly explored. Here we performed both field samplings and pot experiments to investigate the microbial interactions in the maize/faba bean intercropping system, with the focus on the inhibition of Fusarium oxysporum in faba bean plants. Long-term field measurements show that maize/faba bean intercropping increased crop yield, reduced the gene copies of F. oxysporum by 30–84% and increased bacterial richness and Shannon index compared to monocropping. Bacterial networks in intercropping were more stable with more hub nodes than the respective monocultures. Furthermore, the observed changes of whole microbial communities were aligned with differences in the number of siderophore-producing rhizobacteria in maize and pathogen abundances in faba bean. Maize possessed 71% more siderophore-producing rhizobacteria and 33% more synthetases genes abundance of nonribosomal peptides, especially pyochelin, relative to faba bean. This was further evidenced by the increased numbers of siderophore-producing bacteria and decreased gene copies of F. oxysporum in the rhizosphere of intercropped faba bean. Four bacteria (Pseudomonas spp. B004 and B021, Bacillus spp. B005 and B208) from 95 isolates antagonized F. oxysporum f. sp. fabae. In particular, B005, which represented a hub node in the networks, showed particularly high siderophore-producing capabilities. Intercropping increased overall bacterial diversity and network complexity and the abundance of siderophore-producing bacteria, leading to facilitated pathogen suppression and increased resistance of faba bean to F. oxysporum. This study has great agronomic implications as microorganisms might be specifically targeted to optimize intercropping practices in the future.

The need to make more accurate grain demand (GD) forecasting has become a major topic in the current international grain security discussion. Our research aims to improve short-term GD prediction by establishing a multi-factor model that integrates the key factors: shifts in dietary structures, population size and age structure, urbanization, food waste, and the impact of COVID-19. These factors were not considered simultaneously in previous research. To illustrate the model, we projected China’s annual GDP from 2022 to 2025. We calibrated key parameters such as conversion coefficients from animal foods to feed grain, standard person consumption ratios, and population size using the latest surveys and statistical data that were either out of date or missing in previous research. Results indicate that if the change in diets continued at the rate as observed during 2013–2019 (scenario 1), China’s GD is projected to be 629.35 million tons in 2022 and 658.16 million tons in 2025. However, if diets shift to align with the recommendations in the Dietary Guideline for Chinese Residents 2022 (scenario 2), GD would be lower by 5.9–11.1% annually compared to scenario 1. A reduction in feed grain accounts for 68% of this change. Furthermore, for every 1 percentage point increase in the population adopting a balanced diet, GD would fall by 0.44–0.73 million tons annually during that period. Overlooking changes in the population age structure could lead to an overprediction of annual GDP by 3.8% from 2022 to 2025. With an aging population, China’s GD would fall slightly, and adopting a balanced diet would not lead to an increase in GD but would have positive impacts on human health and the environment. Our sensitivity analysis indicated that reducing food waste, particularly cereal, livestock, and poultry waste, would have significant effects on reducing GD, offsetting the higher demand due to rising urbanization and higher incomes. These results underscore the significance of simultaneous consideration of multiple factors, particularly the dietary structure and demographic composition, resulting in a more accurate prediction of GD. Our findings should be useful for policymakers concerning grain security, health, and environmental protection.

Abstract Both mutualistic and pathogenic soil microbes are known to play important roles in shaping the fitness of plants, likely affecting plants at different life cycle stages. In order to investigate the differential effects of native soil mutualists and pathogens on plant fitness, we compared survival and reproduction of two annual tallgrass prairie plant species (Chamaecrista fasciculata and Coreopsis tinctoria) in a field study using 3 soil inocula treatments containing different compositions of microbes. The soil inocula types included fresh native whole soil taken from a remnant prairie containing both native mutualists and pathogens, soil enhanced with arbuscular mycorrhizal (AM) fungi derived from remnant prairies, and uninoculated controls. For both species, plants inoculated with native prairie AM fungi performed much better than those in uninoculated soil for all parts of the life cycle. Plants in the native whole prairie soil were either generally similar to plants in the uninoculated soil or had slightly higher survival or reproduction. Overall, these results suggest that native prairie AM fungi can have important positive effects on the fitness of early successional plants. As inclusion of prairie AM fungi and pathogens decreased plant fitness relative to prairie AM fungi alone, we expect that native pathogens also can have large effects on fitness of these annuals. Our findings support the use of AM fungi to enhance plant establishment in prairie restorations.

Understanding the effects of arbuscular mycorrhizal fungi (AMF) under different environmental contexts on overyielding in intercropping systems can be instructive in optimizing productivity and ecosystem services. A greenhouse study was conducted with maize and faba bean monocultures or intercropping at low phosphorus (P) and high P levels with three different water availabilities, and inoculated with or without AMF species Funneliformis mosseae. At low P level, overyielding was mainly due to the increase of maize biomass promoted by AMF relative to faba bean. Whereas in high P soils, overyielding was observed at all treatments, regardless of AMF. Inoculation of AMF significantly improved maize rather than faba bean P uptake, water use efficiency and photosynthesis rate, in particular at the low P level. This study identified the context dependence of AMF in influencing overyielding in maize/faba bean intercropping and demonstrates the importance of AMF in sustainable agricultural production.

In order to improve the pressure distribution, the aerostatic circular thrust bearing with single supply hole was studied. In the computational fluid dynamics (CFD) simulation, the laminar model, the turbulent model, the mixture model of laminar and turbulent were used simultaneously. The micro-characteristics of the gas flows were analysed based on the simulation results. One test rig was built for measuring the pressure distribution with the single test hole, and the calculated and experimental results were compared. The results showed that when the gas film clearance is small and the gas flow is subsonic completely, the whole gas flow is laminar flow, which should be calculated based on the laminar model and when the gas film thickness is large and there is supersonic flow in some region, which should be calculated according to the mixture model; at the same time, there is no surface of discontinuity for Mach number and pressure distribution, and no shock, and the pressure is recovered due to the boundary layer separation, the change of the flow state and the change of viscosity. The method for testing the pressure distributions with a single test hole is effective.

Vibrio parahaemolyticus is a leading cause of food-borne gastroenteritis worldwide. Although this bacterium has been the subject of much research, the population structure of clinical strains from worldwide collections remains largely undescribed, and the recorded outbreaks of V. parahaemolyticus gastroenteritis highlight the need for the subtyping of this species. We present a broad phylogenetic analysis of 490 clinical V. parahaemolyticus isolates from 17 coastal countries through multilocus sequence analysis (MLST). The 490 tested isolates fell into 161 sequence types (STs). The eBURST algorithm revealed that the 161 clinically relevant STs belonged to 8 clonal complexes, 11 doublets, and 94 singletons, showing a high level of genetic diversity. CC3 was found to be a global epidemic clone of V. parahaemolyticus, and ST-3 was the only ST with an international distribution. recA was observed to be evolving more rapidly, exhibiting the highest degree of nucleotide diversity (0.028) and the largest number of polymorphic nucleotide sites (177). We also found that the high variability of recA was an important cause of differences between the results of the eBURST and ME tree analyses, suggesting that recA has a much greater influence on the apparent evolutionary classification of V. parahaemolyticus based on the current MLST scheme. In conclusion, it is evident that a high degree of genetic diversity within the V. parahaemolyticus population and multiple sequence types are contributing to the burden of disease around the world. MLST, with a fully extractable database, is a powerful system for analysis of the clonal relationships of strains at a global scale. With the addition of more strains, the pubMLST database will provide more detailed and accurate information, which will be conducive to our future research on the population structure of V. parahaemolyticus.

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in China, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 120 Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering capacity. Then the progress in this area in China is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint. [ABSTRACT FROM AUTHOR]