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Thermodynamic databases are essential to understanding alloy properties and guiding materials design. In this work, the mixing enthalpies of the liquid phase in the Gd-Te, Dy-Te and Ho-Te binary systems are calculated using Ab-initio Molecular Dynamics (AIMD) simulations and the thermodynamic parameters are determined using the CALculation of PHAse Diagrams (CALPHAD) method combined with the phase equilibrium data and thermodynamic data. The associated solution model is employed to describe the liquid phase of these systems. The sublattice model (Gd,Te)0.0296(Gd)0.4(Te)0.5714, (Dy,Te)0.0286(Dy)0.4286(Te)0.5714 and (Ho,Te)0.5(Te)0.5 are utilized to describe Gd2Te3, Dy2Te3 and HoTe, respectively. The line compounds, i.e. GdTe, DyTe, and DyTe2, are modeled using the stoichiometric model. The calculated results can describe the experimental and thermodynamic information reported in the literature. In addition, the existence of a liquid-liquid separation in the Dy-rich side in the Dy-Te binary system is proposed in this work. [ABSTRACT FROM AUTHOR]

[Display omitted] • The reducing capacity of HA demonstrated a continuous increase while composting. • The ORC of compost-derived HA is higher than IRC. • Adsorption occurs in HA and FeCit by aliphatic and out-of-plane aromatic C H. • The adsorption releases free hydrogen and increases the iron-binding site. The reducing capacity (RC) of compost-derived humic acid (HA) is related to the type and number of redox-active functional moieties in its structure and has a considerable environmental influence on its geochemical redox cycle. Composting treatment can affect the redox-active fractions of organic substances through microbial transformation and degradation. However, the relationship between the RC of compost-derived HA and its fluorescence component and infrared spectra remains unclear. In this study, we assessed the response of the organic reducing capacity (ORC) and inorganic reducing capacity (IRC) of compost-derived HA to the stabilization of organic solid waste materials by analyzing the redox-active functional groups of HA extracted at different composting times. The results demonstrated that the RC of compost-derived HA continuously increased during composting because of the formation of fulvic- and humic-like fluorescent components, which consist of amide, phenolic hydroxyl, quinone, and aromatic groups. Adsorption occurred between HA and FeCit by aliphatic and out-of-plane aromatic C H, which released free hydrogen and increased the Fe-binding site; consequently, ORC was obviously higher than IRC. The results of this study could provide an understanding of the transformation of the fluorescent substances and functional groups that affect redox properties during composting; therefore, this study has considerable significance for exploring the application of compost products. [ABSTRACT FROM AUTHOR]

A multi-component Freon gas sensing system was developed based on the non-dispersive infrared (NDIR) spectroscopy, which had the advantages of simple structure and low cost. This system mainly consisted of a broadband infrared light source, a tunable Fabry-Perot (FP) detector and a small brass absorption cell. In order to improve the utilization rate of infrared light source, the absorption cell was optimized. H1301, R134a and R410A were simultaneously detected through the measurement of gas absorption spectrum. The spectral range of the FP detector was from 8.0 to 10.5 μm, and the entire spectrum was recorded by wavelength scanning. The area of measured absorbance was directly proportional to the concentration of the target gas, which was used to calibrate the sensing system. The temperature and frequency response characteristics of the system were tested. The experimental results showed that the higher the temperature, the lower the responsiveness. In addition, the system had the best signal-to-noise ratio (SNR) at 10 Hz. The minimum detection limits of H1301, R134a and R410A were achieved to be 2.5 ppm, 5.3 ppm and 4.8 ppm, respectively. The cross-interference among the gases was suppressed by using BP neural network. • Non-dispersive infrared spectroscopy. • Fabry-Perot detector. • Multi-component gas detection. • BP neural networks. [ABSTRACT FROM AUTHOR]

The Co-Cu-Sn ternary system has been modeled based on reported phase equilibrium data in the literature using the CALPHAD (CALculation of PHAse Diagrams) method. The excess Gibbs energies of solution phases, including liquid, Bcc, Fcc and Hcp, are expressed by the Redlich-Kister polynomial. The two-sublattice model (Co,Cu)m(Sn)n is used to describe the solid solution of binary intermetallic compounds, i.e. CoSn3, CoSn2 Cu3Sn and βCu6Sn5 in the Co-Cu-Sn ternary system. Co3Sn2 was described using the four-sublattice model (Co,Cu,Sn)1(Cu,Sn)1(Co,Va)0.5(Co,Va)0.5. The ternary stoichiometric compound Co2Cu8Sn3 is modeled by the stoichiometric model, Co2Cu7.5Sn3. Finally, a set of self-consistent parameters which can describe the thermodynamics of the Co-Cu-Sn ternary system was obtained. Based on the calculated thermodynamic parameters, the liquidus projection and reaction scheme are also derived in the present work. [ABSTRACT FROM AUTHOR]

The 450 and 600 °C isothermal sections of the Ni-V-Zn ternary system have been investigated through Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and x-ray Diffraction (XRD) technique. Eight three-phase regions have been confirmed at the 450 °C section and nine three-phase regions exist at the 600 °C one. Experimental results indicate that it is difficult for Ni to dissolve in VZn3 and V4Zn5. The solid solubilities of V in γ(Ni2Zn11) and β1(NiZn) are 1.4 and 3.7 at.% at 450 °C, respectively, while V in γ and β1 are 2.5 and 4.0 at.% at 600 °C, respectively. The solid solubilities of Zn in Ni2V7, σ(Ni2V3), Ni2V and Ni3V are 0.5, 4.7, 2.3 and 2.6 at.% at 450 °C as well as 0.5, 9.5, 2.2 and 2.8 at.% at 600 °C, respectively. No ternary compound has been found in this work. [ABSTRACT FROM AUTHOR]

Using CALPHAD method, the Al-Zr, Al-Li and Al-Li-Zr systems have been reassessed based on the latest experimental phase relations from literatures and the first-principle calculation of the formation enthalpy for ternary compound T1(AlLi2Zr) in this work. The excess Gibbs energies of solution phases, including liquid, bcc, fcc and hcp, were expressed by the Redlich–Kister polynomial. The stoichiometric compounds, i.e. Al4Zr5, Al3Zr5, AlZr2, AlZr3, Al2Li3, Al4Li9 and T1(AlLi2Zr), were modeled as stoichiometric model and the non-stoichiometric compounds, i.e. Al3Zr, Al2Zr, Al3Zr2, AlZr, Al3Zr4, Al2Zr3, AlLi2 and T2(AlLix+yZr5−x), were described with different sublattice models. Finally, a set of reasonable thermodynamic parameters for Al-Li-Zr ternary system have been obtained, which notes a clear improvement on the self-consistency. The calculated isothermal section at 470 K of Al-Li-Zr system was in reasonable agreement with the experimental one. [ABSTRACT FROM AUTHOR]

The rapid development of micro-electronics has a growing demand on the heat dissipation performance of devices, especially thermal management materials. However, recent researches focus on the improvement of single ability, such as thermal or mechanical properties. Herein, a strategy that simultaneously improves thermal and mechanical performance of thermal manager material was proposed, which was achieved by preparing Cu-SiC w composites via the co-electrodeposition technology. The influence of electroplating parameters, such as temperature, current density and reinforcement contents, on the microstructure evolution, mechanical and thermal conductivity were investigated systematically. The fabricated SiC w composite displayed excellent shear strength up to 420 MPa, which is resulted from the Orowan strengthening and load transferring. Additionally, the thermal conductivity of 340 W/(m·K) was obtained, owing to the uniform distribution of whiskers and good interface between the Cu matrix and whiskers. Therefore, the presented work provided an effective method for fabricating comprehensive thermal-mechanical properties and homogeneous heat dissipation capacity Cu-SiC w composites and paved the way for the practical application in the field of the connector between the power devices and heat sinks. [ABSTRACT FROM AUTHOR]

The doping with Cu in the Sb-Se material system can effectively reduce power consumption and improve data retention ability of the PCRAM (Phase-Change Random-Access Memory) material. However, no thermodynamic study of the Cu-Sb-Se system has been reported. Therefore, in this work the Cu-Sb-Se system was modeled using the CALPHAD (CALculation of PHAse Diagrams) method. The excess Gibbs energies of solution phases, including liquid and FCC were expressed by the Redlich-Kister polynomial. Two-sublattice model (Cu,Se)2Se was used to describe the solid solution of binary intermetallic compounds, i.e. α-Cu2Se and β-Cu2Se in Cu-Sb-Se ternary system. The compounds, e.g. η(Cu2Sb), β(Cu3Sb), Sb2Se3, α-CuSe, β-CuSe, Pe(Cu3SbSe4) and C(CuSb3Se5) were described as stoichiometric compounds. The temperature of the eutectic reaction γ(Cu17Sb3) = (Cu) + δ(Cu4Sb) in the Cu-Sb system and the temperature of the invariant reaction L1 = L2 + (Sb) in the Sb-Se system were adjusted. A set of self-consistent thermodynamic parameters for the Cu-Sb-Se system was obtained, and the 623, 673, 723, 773, 873 and 973 K isothermal sections, and the liquidus projection and invariant reactions for this ternary system have been calculated. [ABSTRACT FROM AUTHOR]

Unusual force constants originating from the local charge distribution in crystalline GeTe and Sb2Te3 are observed by using the first-principles calculations. The calculated stretching force constants of the second nearest-neighbor Sb-Te and Ge-Te bonds are 0.372 and −0.085 eV/Å2, respectively, which are much lower than 1.933 eV/Å2 of the first nearest-neighbor bonds although their lengths are only 0.17 Å and 0.33 Å longer as compared to the corresponding first nearest-neighbor bonds. Moreover, the bending force constants of the first and second nearest-neighbor Ge-Ge and Sb-Sb bonds exhibit large negative values. Our first-principles molecular dynamic simulations also reveal the possible amorphization of Sb2Te3 through local distortions of the bonds with weak and strong force constants, while the crystalline structure remains by the X-ray diffraction simulation. By identifying the low or negative force constants, these weak atomic interactions are found to be responsible for triggering the collapse of the long-range order. This finding can be utilized to guide the design of functional components and devices based on phase change materials with lower energy consumption. [ABSTRACT FROM AUTHOR]

Sustainable intensification of protected vegetable crops entails increasing yield while reducing environmental impact and labor input. To explore a comprehensive strategy for high yielding, highly efficient and high quality production of greenhouse tomato (Solanum lycopersicum L.), an integrated crop-nitrogen management (ICNM) strategy was compared to farmers' traditional management (TM) in a field experiment in a solar greenhouse. A split-plot block design was used. The main factor was the management strategy of ICNM and TM. The secondary factor was four different basal fertilizer treatments, being a control (CK; 0 kg N ha−1), carbon-based urea (BU; 100 kg N ha−1), controlled release urea (CU; 100 kg N ha−1), and conventional compound fertilizer (CF; 100 kg N ha−1). An additional 200 kg N ha−1 through drip irrigation as topdressing was used. Tomato fruit yield, N uptake, and N partial productivity with ICNM were significantly higher than with TM, increasing by 32.1%, 39.7%, and 31.1%, respectively. The proportion of fine roots was increased in ICNM, and the average diameter of roots decreased by 10.7% compared to TM. There was a significant negative correlation between mean root diameter and N uptake. In conclusion, the ICNM strategy was beneficial to form a good root system configuration, promote the development of shoot biological potential, increase tomato yield, maintain fruit quality, increase N uptake, and reduce environmental risks. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) in oceans poses a significant threat to human health through the seafood supply chain. Ammonia-oxidizing archaea (AOA) are important marine microorganisms and play a key role in the biogeochemical nitrogen cycle around the world. However, the AMR of marine AOA to aquicultural antibiotics is poorly explored. Here, Raman-deuterium isotope probing (Raman-DIP), a single-cell tool, was developed to reveal the AMR of a typical marine species of AOA, Nitrosopumilus maritimus (designated SCM1), against six antibiotics, including erythromycin, tetracycline, novobiocin, neomycin, bacitracin, and vancomycin. The D 2 O concentration (30% v/v) and culture period (9 days) were optimized for the precise detection of metabolic activity in SCM1 cells through Raman-DIP. The relative metabolic activity of SCM1 upon exposure to antibiotics was semi-quantitatively calculated based on single-cell Raman spectra. SCM1 exhibited high resistance to erythromycin, tetracycline, novobiocin, neomycin, and vancomycin, with minimum inhibitory concentration (MIC) values between 100 and 400 mg/L, while SCM1 is very sensitive to bacitracin (MIC: 0.8 mg/L). Notably, SCM1 cells were completely inactive under the metabolic activity minimum inhibitory concentration conditions (MA-MIC: 1.6–800 mg/L) for the six antibiotics. Further genomic analysis revealed the antibiotic resistance genes (ARGs) of SCM1, including 14 types categorized into 33 subtypes. This work increases our knowledge of the AMR of marine AOA by linking the resistant phenome to the genome, contributing to the risk assessment of AMR in the underexplored ocean environment. As antibiotic resistance in marine microorganisms is significantly affected by the concentration of antibiotics in coastal environments, we encourage more studies concentrating on both the phenotypic and genotypic antibiotic resistance of marine archaea. This may facilitate a comprehensive evaluation of the capacity of marine microorganisms to spread AMR and the implementation of suitable control measures to protect environmental safety and human health. [Display omitted] • The AMR of AOA was revealed by linking the resistant phenome to the genome. • D 2 O concentration and culture period were optimized via Raman-DIP. • MA-MIC was proposed for non-growing but metabolically active SCM1 cells. • ARGs of SCM1 including 14 types categorized into 33 subtypes were unveiled. [ABSTRACT FROM AUTHOR]

Te-based alloys are widely used for Phase Change Random Access Memory (PCRAM). The investigation of the Te-based phase diagram gives significant benefit to the development of Te-based PCRAM materials. Thermodynamic modelling of the Te-X (X = Cu, Ga, Li, Sr) systems has been carried out using the CALculation of PHAse Diagrams (CALPHAD) method based on the enthalpies of formation calculated by first-principles calculations in the present work and available experimental data in the literature. In the Te-Cu, Te-Ga and Te-Li systems, the liquid phases were separately described by the associated solution model with Cu2Te, Ga2Te3 and Li2Te associate species. A set of self-consistent thermodynamic parameters for the Te-X (X = Cu, Ga, Li, Sr) systems was obtained. Comparison between the calculated results and available experimental data indicates that most experimental information can be satisfactorily accounted for by modelling. [ABSTRACT FROM AUTHOR]

Thermodynamic descriptions of the Bi-Se and Bi-Te systems have been developed using the CALculation of PHAse Diagrams (CALPHAD) method based on the experimental data available in the literature. The liquid phases were described by the associated solution model for the Bi-Se and Bi-Te systems with Bi2Se3 and Bi2Te3 as associates, respectively. The intermetallics Bi2Se3, Bi3Se4, Bi8Se9, BiSe, Bi8Se7, Bi4Se3, Bi3Se2, Bi4Te5, Bi8Te9, BiTe, Bi4Te3, Bi2Te and Bi7Te3 were treated as stoichiometric compounds while Bi2Te3 was modeled by the sublattice model based on its homogeneity range and crystal structure. A set of self-consistent thermodynamic parameters for the Bi-Se and Bi-Te systems was obtained. Comparisons between the calculated results and experimental data available in the literature show that the most reliable experimental information can be satisfactorily accounted for by the present modeling. [ABSTRACT FROM AUTHOR]

Objective: To screen the risk factors affecting the recurrence risk of patients with ampullary carcinoma (AC)after radical resection, and then to construct a model for risk prediction based on Lasso-Cox regression and visualize it. Methods: Clinical data were collected from 162 patients that received pancreaticoduodenectomy treatment in Hebei Provincial Cancer Hospital from January 2011 to January 2022. Lasso regression was used in the training group to screen the risk factors for recurrence. The Lasso-Cox regression and Random Survival Forest (RSF) models were compared using Delong test to determine the optimum model based on the risk factors. Finally, the selected model was validated using clinical data from the validation group. Results: The patients were split into two groups, with a 7:3 ratio for training and validation. The variables screened by Lasso regression, such as CA19-9/GGT, AJCC 8th edition TNM staging, Lymph node invasion, Differentiation, Tumor size, CA19-9, Gender, GPR, PLR, Drinking history, and Complications, were used in modeling with the Lasso-Cox regression model (C-index = 0.845) and RSF model (C-index = 0.719) in the training group. According to the Delong test we chose the Lasso-Cox regression model (P = 0.019) and validated its performance with time-dependent receiver operating characteristics curves(tdROC), calibration curves, and decision curve analysis (DCA). The areas under the tdROC curves for 1, 3, and 5 years were 0.855, 0.888, and 0.924 in the training group and 0.841, 0.871, and 0.901 in the validation group, respectively. The calibration curves performed well, as well as the DCA showed higher net returns and a broader range of threshold probabilities using the predictive model. A nomogram visualization is used to display the results of the selected model. Conclusion: The study established a nomogram based on the Lasso-Cox regression model for predicting recurrence in AC patients. Compared to a nomogram built via other methods, this one is more robust and accurate. [ABSTRACT FROM AUTHOR]

In this letter, a portable trace carbon dioxide (CO2) measurement instrument based on photoacoustic spectroscopy (PAS) was proposed and designed. The nonresonance PA cell (PAC) including a cooper tube with 251.2 μl was designed. Two condenser microphones were used to measure the PA signal simultaneously. The center wavelength of the distributed feedback laser was chosen to 2004 nm. Within 1 s integral time, the detection limit for CO2 reached 12.7 ppm. The normalized noise‐equivalent absorption coefficient was calculated to be 4.8468 × 10−9 cm−1W/Hz1/2. With Allan‐Werle deviation analysis, the measurement detection limit for CO2 improved to 4 ppm with 30 s integration time. As a result, the trace CO2 instrument based on PAS shows a good performance in long‐term detection. [ABSTRACT FROM AUTHOR]

We designed and manufactured a set of high-sensitivity photoacoustic (PA) gas detector based on differential multi-pass cell (DMPC) with a chamber volume of only 162 mL, which realized real-time online monitoring of CH 4 in the atmosphere. The effective absorption optical path of DMPC reached 4.92 m, which enhanced the PA signal from the two dimensions of optical excitation and acoustic resonance. A 3D-printed muffler was integrated into the detector to eliminate the gas flow noise generated by the pump. A 1651 nm distributed feedback (DFB) laser was used to accomplish the measurement of CH 4. The analysis results showed that the minimum detection limit (MDL) of CH 4 reached 0.6 ppb with an averaging time of 500 s. In addition, the normalized noise equivalent absorption (NNEA) coefficient was 1.79 × 10−10 cm−1 W/Hz1/2. Continuous flow monitoring of CH 4 in the atmosphere was carried out to confirm the reliability and feasibility of the PA system based on DMPC. • A high-sensitivity photoacoustic (PA) gas detector based on differential multi-pass cell (DMPC) was presented. • A DMPC with 30 reflections for an effective absorption optical path length of 4.92 m was designed. • The minimum detection limit (MDL) reached 0.6 ppb with an integration time of 500 s. • The normalized noise equivalent absorption (NNEA) coefficient was equal to 1.79 × 10−10 cm−1 W/Hz1/2. • We have carried out continuous flow real-time detection of the concentration of CH 4 in atmosphere for 72 h. [ABSTRACT FROM AUTHOR]

The microbial reduction of Fe(III) minerals (MRF) is an important process in paddy soil because it can affect the biogeochemical cycles of many major and trace elements. Natural organic matter (NOM) that mainly exists in the form of solid phase in soil can mediate MRF through electron shuttling functionality. However, whether a link exists between solid-phase NOM-mediated MRF in soil and the age of paddy field since the reclamation on fallow is unclear. Here, we use microbial reduction method to assess the solid-phase NOM-mediated MRF of paddy soils with different reclamation ages. The results show that solid-phase NOM-mediated MRF exhibits a positive response to land use change sequence from fallow to paddy field, indicating that the long-term natural development of paddy field favors the electron shuttling of NOM between cells and Fe(III) minerals. This increase in the electron shuttling of NOM is not due to the increase in the redox functional groups of NOM, but may be attributed to the formation of NOM-mineral complex through the synergistic increases in NOM content and transformation of soil texture from clay loam to loam. The decrease in the redox potential of Fe(III) minerals in soil caused by decreased pH and the increase in Fe content in the organic matter-complexed form may also partly facilitate electron transfer from NOM to Fe(III) minerals. Our work is useful in predicting the role of soil solid-phase NOM in mediating MRF in the context of long-term reclamation of paddy field and provides guidance for the environmental management of paddy fields. Unlabelled Image • Soil solid-phase organic matter-mediated microbial Fe(III) reduction increased with land use change sequence. • This increase was independent of the changes in redox-active functional groups of natural organic matter (NOM). • This increase was dependent on the changes in NOM content and in soil texture from clay loam to loam. • This increase was partly due to the decreased soil pH and increased NOM-complexed Fe. [ABSTRACT FROM AUTHOR]

[Display omitted] • The removal of UV 254 after adsorption by g-CN were 30 ∼ 70% for all the leachate. • Humic acids were selectively adsorbed with a high selectivity coefficient (>3.06). • The recovery rate and purity of the adsorbed humic-like components reached 100%. • The major mechanisms were π-π interactions and conformation-variation effect. Selective adsorption of humic acids is innovative in landfill leachate treatment, since it can both address the UV quenching substance (UVQS) problems and recover humic acids as liquid fertilizers applied in agriculture and forestry. However, due to lacking available adsorbents, it remains a great challenge. Herein, we evaluated the application of graphitic carbon nitride (g-CN) for selective adsorption of humic acids from landfill leachate. First, 10 types of leachate were considered and characterized, and the leachate contained humic acids of different contents. The common method was used to prepare g-CN with similar properties to the previously reported counterparts. Then, kinetics, isotherms, and removal for adsorption of the leachate by g-CN were studied. It was found that the adsorption was fast and controlled by the surface and intraparticle diffusion. For all the leachate, the removal of UV absorbance at 254 nm (UV 254) was 30 ∼ 70%, much greater than that for total organic carbon. In particular, the UV 254 removal was mainly contributed by the selective adsorption of humic acids with a high selectivity coefficient (>3.06). The recovery rate and purity of the adsorbed humic-like components were 100% in some cases. Finally, the mechanisms for selective adsorption were elucidated. The results revealed that, in addition to the major π-π interactions, the adsorption was affected by electrostatic interactions and hydrogen bondings, along with the newly proven conformation-variation effect. The findings will expand a promising direction for disposal of landfill leachate. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) have been proven to play critical roles in epithelial-mesenchymal transition (EMT) and metastasis of lung cancer. However, the biological functions and related mechanisms of lncRNAs are unclear. In addition, the EMT-based prognosis prediction in lung cancer still lacks investigation. Here, we established the methodology of identifying critical metastasis-related lncRNAs using comprehensive datasets of cancer transcriptome, genome and epigenome, and also provided tools for prognosis prediction in lung cancer. Initially, important mesenchymal marker genes were identified to compose the tumor mesenchymal score, which predicted patient prognosis in lung cancer, especially lung adenocarcinoma (LUAD). The score was also correlated with several crucial biological and physiological processes, such as tumor immune and hypoxia. Based on the score, lung cancer patients was classified into epithelial and mesenchymal subtypes, and lncRNAs which exhibited expressional dysregulation, promotor methylation alteration and copy number variation between the two subtypes in LUAD were identified and underwent further prognostic analyses. Finally, we identified 14 lncRNAs as EMT-related and significant biomarkers in prognosis prediction of LUAD. As validation, lncRNA RBPMS-AS1 was proven to be co-expressed with epithelial biomarkers, suppressive for A549 cell migration, invasion and EMT, and also significantly associated with better outcomes of LUAD patients, suggesting the potential of RBPMS-AS1 to serve as a lncRNA epithelial biomarker in metastasis of LUAD. Based on the identified lncRNAs, an EMT-linked lncRNA prognostic signature was further established. Taken together, our study provides robust predictive tools, potential lncRNA targets and feasible screening strategies for future study of lung cancer metastasis. [ABSTRACT FROM AUTHOR]

Soil fungi are key drivers in regulating the ecosystem function, playing a vital role in protecting the plant from phytopathogens and other biotic and abiotic pressures. However, the potential impact of compost addition and soil aggregate size on the fungal community and functional ecological guild remains uncertain. This study investigated the structure, composition, and function of soil fungal communities across aggregate fractions under food waste compost addition using Miseq sequencing and FUNGuild. Compost addition exerted a negative impact on fungal α-diversity, and shifted the structure and changed the composition of fungal community. Compost addition rates exhibited more contributions to fungal α-diversity variations (R = 0.609, 0.895, and 0.501 for Sobs, Shannon, and Chao indices, respectively, P = 0.001) and the separation of community structure than soil aggregate size (R = 0.952, P = 0.001). Biomarkers, including Chaetomiaceae, Ascobolaceae, and Sordariomycete, displayed significant superiority in compost-added soils, whereas the populations of Nectriaceae and Clavicipitaceae were significantly decreased. The relative abundances of animal and plant pathogens were significantly decreased, whereas that of saprotrophs were increased. The abundances of pathogens correlated positively with pH and negatively with nutrients (soil organic matter, dissolved organic carbon, total nitrigen, NH 4 +, and NO 3 −), whereas those of saprotrophs showed an opposite trend. The dose of compost was the major driver for fungal functional guild variation, whereas carbon and nitrogen source exhibited more contributions to function variation than pH value. These results provide a reference for sustainable ecological agriculture by applying compost rationally under the conditions of soil health and agricultural performance. Unlabelled Image • Compost addition reduced animal and plant pathogens in soil. • Compost addition increased abundance of saprotrophic fungi in soil. • Pathogens were positive correlated with pH and negative with soil nutrients. • Chaetomiaceae , Ascobolaceae and Sordariomycete were biomarkers in amended soil. • Compost ratio drive fungal community more than soil phy-chemical properties. [ABSTRACT FROM AUTHOR]

• Heavy metals showed more contribution to bacterial community and N-transforming genes variation than soil chemical factors. • Treated wastewater exerted positive impact on amo A abundance and negative effect on nif H abundance. • Interactions between heavy metals and soil chemical factors strengthened the capacity of denitrification in topsoil. • Interactions between heavy metals and soil chemical factors enhanced the capacity of ammoxidation in deeper soil. Irrigation with treated wastewater (TWW) influences soil ecological function due to the accumulation of heavy metals (HMs) and nutrients in soils. However, the interaction between HMs and microbial processes in TWW-irrigated soil has not been fully explored. We investigated the effect of HMs on bacterial communities and nitrogen-transforming (N-transforming) genes along vertical soil profiles irrigated with domestic TWW (DTWW) and industrial TWW (ITWW) for more than 30 years. Results indicate that long-term TWW irrigation reshaped bacterial community structure and composition. Irrigation with ITWW led to increased accumulation of Cd, Cr, Cu, Pb, Zn, and Ni in soils than DTWW. Accumulation of inorganic N, soil organic carbon, and HMs in topsoil irrigated with ITWW contributed to the activities of Micrococcaceae. The effect of the activation of nutrient factors on Bacillus , which was the dominant species in DTWW-irrigated soils, was greater than that of HMs. HM pressure driven by ITWW irrigation changed the vertical distribution of N-transforming functional genes, increasing the abundance of amo A gene and decreasing that of nif H through soil depth. ITWW irrigation enhanced the denitrification capacity in topsoil; ammonia-oxidizing capacity in deeper soil was increased after long-term irrigation with DTWW and ITWW, suggesting a potential risk of nitrogen loss. [ABSTRACT FROM AUTHOR]

Highlights Microplastics can alter the physicochemical and biogeochemical processes in soil, but whether these alterations have further the effects on the transformation of soil heavy metal speciation, and if so, whether these effects vary across soil aggregate levels remain unknown. Herein, long-term soil culture experiments and soil fractionation are combined to investigate the effects of microplastics on chemical speciation of Cu, Cr, and Ni with different particle-size soil aggregates. Results show that microplastics in soil decrease the exchangeable, carbonate-bound, and Fe-Mn oxide-bound fractions of metals but increase their organic-bound fractions via direct adsorption and indirect effects on the soil microenvironment conditions. The findings suggest that microplastics can promote the transformation of heavy metal speciation from bioavailable to organic bound. Such promotion exerts notable differences across soil aggregate levels. The transformation of soil heavy metal speciation is greater in larger aggregates than in smaller aggregates in the early incubation period with microplastics but shows the opposite trend in the later incubation period. Therefore, this process is more sensitive to long-term microplastic pollution in smaller aggregates than in larger aggregates, most likely owing to the lag in the influence of microplastics on metal speciation transformation in the smaller aggregates. [ABSTRACT FROM AUTHOR]

• Electrochemical measurements were used to assess the redox property of soil solid-phase HS. • The link between redox property of solid-phase HS and physico-chemical protections in soils. • Soil particulate HS exert the greatest microbially reducible extent. • Soil non-aggregated clay associated HS exert the lowest microbially reducible extent. A significant fraction of humic substances (HS) in natural soils is protected due to the interactions with mineral surfaces or occlusion within aggregates and clay microstructures, which could render the solid-phase HS less spatially accessible to microorganisms and thus affect their extracellular electron transfer. However, more diverse and convincing evidence is needed to further verify the link between extracellular electron transfer of solid-phase HS and their physico-chemical protection mechanisms in soils. In this study, soil physical fractionation and mediated electrochemical measurements were combined for the first time to assess the microbially reducible extents of solid-phase HS in mineral soils. The results show that the solid-phase HS in soil contain several pools with different microbially reducible extents, due to the fact that different pools employ distinct protection mechanisms of soil organic matter against microbial attacks; the particulate HS exert the greatest microbially reducible extent, followed by the microaggregate occluded HS and non-aggregated silt associated HS, and non-aggregated clay associated HS exert the lowest microbially reducible extent. Our work provides a new evidence to validate the view that the extracellular electron transfer process of solid-phase HS in natural soils is largely controlled by their physico-chemical protection mechanisms. [ABSTRACT FROM AUTHOR]

Biochar is widely used in the environmental-protection field. This study presents the first investigation of the mechanism of biochar prepared using iron (Fe)-rich biomass and its impact on the reductive removals of Orange G dye by Shewanella oneidensis MR-1. The results show that biochars significantly accelerated electron transfer from cells to Orange G and thus stimulated reductive removal rate to 72–97%. Both the conductive domains and the charging and discharging of surface functional groups in biochars played crucial roles in the microbial reduction of Orange G to aniline. A high Fe content of the precursor significantly enhanced the conductor performance of the produced biochar and thus enabled the biochar to have a higher reductive removal rate of Orange G (97%) compared to the biochar prepared using low-Fe precursor (75%), but did not promote the charging and discharging capacity of the produced biochar. This study can prompt the search for natural biomass with high Fe content to confer the produced biochar with wide-ranging applications in stimulating the microbial reduction of redox-active pollutants. [ABSTRACT FROM AUTHOR]