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The aim of this study is to accurately evaluate the quality characteristics of whole tillage cropland and deepen the knowledge of sub-tillage soil quality evaluation in Jilin Province, China. In this study, top-tillage and sub-tillage soil samples were collected from 185 maize continuous cropping areas in Jilin Province, and 12 physicochemical indexes (pH, cation exchange capacity (CEC), soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), sand, silt, and clay) were used to evaluate the whole tillage layer soil quality index (SQI). The results showed that the whole tillage soil physicochemical indexes in Jilin Province were generally above the moderate level, and nutrient contents increased from West to East among the regions. The minimum data set SQI (SQI-MDS) of the top-tillage and sub-tillage layers were 0.22–0.98 (0.46) and 0.23–0.93 (0.55), respectively. The suitable ranges of MDS parameters for reasonable tillage layers were as follows: top-tillage layer SOM ≥ 34.5 g kg−1, 31.5% ≤ sand ≤ 53.5%, AP ≥ 32.1 mg kg−1, and TK ≥ 15.18 g kg−1; sub-tillage layer 31.3% ≤ sand ≤ 51.2%, TN ≥ 1.48 g kg−1, 6.4 ≤ pH ≤ 7.1, and AK ≥ 157.6 mg kg−1. In summary, the SQI and evaluation indexes of the top-tillage and sub-tillage layers in different ecological zones are varied. It is necessary to adjust the evaluation index thresholds in combination with the actual conditions to establish a more accurate evaluation index system of the whole tillage soil quality. [ABSTRACT FROM AUTHOR]

Returning crop residues to the field after harvesting is a proven effective strategy for improving soil fertility, carbon sequestration, and crop productivity. However, the relationships between crop residue return modes, SOC and nutrient contents, and crop yields are still unclear. In this study, a field trial was conducted to investigate the effects of different maize straw return modes, i.e., straw mulching (SMU), straw deep ploughing (SDP), and control without straw return (CK), on soil organic carbon (SOC) and nutrient contents in soil layers of 0–40 cm in a Mollisol. The relationships between straw return modes, SOC and nutrient contents, and maize yield were evaluated. Compared with CK, SMU and SDP significantly increased SOC, total nitrogen (N), available N, total phosphorus (P), and available P contents in all soil layers. Relative to SMU, SOC, total N, available N, total P, and available P contents were significantly lower in soil layers of 0–10 cm, but they were significantly higher in soil layers of 20–40 cm in SDP. Redundancy analysis indicated that total N, available N, and SOC were major factors controlling maize yield. Structural equation modeling further showed that straw return modes indirectly affected maize yield by directly and preferentially affecting total N and available N contents. The results indicated that SMU and SDP were beneficial for increasing SOC and nutrient contents at the surface and subsurface soils, respectively. Optimizing a nitrogen management strategy is important to achieve high maize yield with straw return. [ABSTRACT FROM AUTHOR]

Maize ( Zea mays L.) root morphology exhibits a high degree of phenotypic plasticity to nitrogen (N) deficiency, but the underlying genetic architecture remains to be investigated. Using an advanced BC4F3 population, we investigated the root growth plasticity under two contrasted N levels and identified the quantitative trait loci (QTLs) with QTL-environment (Q × E) interaction effects. Principal components analysis (PCA) on changes of root traits to N deficiency (ΔLN-HN) showed that root length and biomass contributed for 45.8% in the same magnitude and direction on the first PC, while root traits scattered highly on PC2 and PC3. Hierarchical cluster analysis on traits for ΔLN-HN further assigned the BC4F3 lines into six groups, in which the special phenotypic responses to N deficiency was presented. These results revealed the complicated root plasticity of maize in response to N deficiency that can be caused by genotype-environment (G × E) interactions. Furthermore, QTL mapping using a multi-environment analysis identified 35 QTLs for root traits. Nine of these QTLs exhibited significant Q × E interaction effects. Taken together, our findings contribute to understanding the phenotypic and genotypic pattern of root plasticity to N deficiency, which will be useful for developing maize tolerance cultivars to N deficiency. [ABSTRACT FROM AUTHOR]

Facing the combined pollution of antibiotics and heavy metals caused by livestock excrement and industrial effluents, how to use microbial technology to remove these pollutants simultaneously is an important research topic in environmental remediation. In addition, quick separation of the bacteria-water after remediation is also an urgent problem. In this study, we gradually developed a dual-bacteria microbial treatment technology capable of removing Pb(Ⅱ), Cd(Ⅱ) and common antibiotics, as well as self-settling after treatment. The key technology in this study mainly includes modifying the bacterial membrane proteins using Pb-binding protein PbrR, Cd-binding protein CadR and bacterial laccase CotA via surface-display technology to maximize the removal of Pb(Ⅱ), Cd(Ⅱ) and antibiotics, separately. Besides, the introduction of nanobody-antigen adhesion facilitated the self-settling in dual-bacterial system. Then, we studied its effectiveness in removing single pollutants, analyzed the influence of different heavy metal ions, and conducted detailed studies on the kinetics. Further characterization of heavy metal biosorption behavior was conducted using SEM, SEM-EDS, FTIR, and XPS techniques. Via protein fusion and dual vector expression, we constructed a dual-bacteria treatment system that could achieve rapid, selective removal of combined pollutants at a wide pH range temperature range, ultimately precipitating at bottom. Finally, molecular dynamics simulation was employed to elucidate the molecular mechanism underlying the selective biosorption by metal-binding proteins. The findings in this study hold significant implications for achieving selective pollutant removal using engineering bacteria in complex water environments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

To address the contamination caused by DBP residues prevalent in black soils, this study developed a multifunctional bioremediation material (BHF@DK-P3) using humic acid and iron-modified corn stover biochar in combination with microbiota. The microbiota contained DBP-degrading bacteria (Enterobacterium sp. DNB-S2), phosphorus-solubilizing bacteria (Enterobacter sp. P1) and potassium-solubilizing bacteria (Paenibacillus sp. KT), and formed a good mutualistic symbiosis. In the biochar microenvironment, the microflora had lower DBP biotoxicity responses and more cell membrane formation. The addition of BHF@DK-P3 brought the structure of the DBP-contaminated black soil closer to the optimal three-phase ratio. The microbiota was able to perform their biological functions stably under both DBP stress and acid-base stress conditions. The stability of soil aggregates and the efficiency of N, P, K nutrients were improved, with available phosphorus increasing by 21.45%, available potassium by 12.54% and alkali-hydrolysable nitrogen by 14.74%. The relative abundance of copiotrophic bacterial taxa in the soil increased and the relative abundance of oligotrophic bacterial taxa decreased, providing a good mechanism for the conversion and utilization of soil nutrients. Biochar and microbiota jointly influenced soil carbon and nitrogen metabolism in response to DBP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: To study the relationship between fibrotic focus (FF) and carbonic anhydrase (CA) IX in invasive ductal carcinomas (IDC) of the breast., Methods: In 167 cases of IDC, the FF was assessed morphologically, and expression of ER, PR and CA IX was evaluated using MaxVision immunohistochemistry., Results: The expression of CA IX in IDC with and without FF was 56.3% (45/80) and 28.7% (25/87) respectively, with significant difference (P=0.001). In IDC with FF, the CA IX expression of tumor cells in tumors with CA IX-positive fibroblasts (35/40, 87.5%) was significantly (P<0.001) higher than that in tumors with CA IX-negative fibroblasts (10/40, 25.0%). In IDC with FF, the CA IX expression of fibroblasts of FF in grade 3 IDC (23/33, 69.7%) was significantly (P=0.006) higher than that in grade 1+2 tumors (17/47, 36.2%). The ER and PR expression of tumor cells in tumors containing CA IX-negative fibroblasts was 72.5% (29/40) and 65.0% (26/40) respectively, whereas the ER and PR expression of tumor cells in tumors containing CA IX-positive fibroblasts was 50.0% (20/40) and 42.5% (17/40) respectively; the difference was statistically significant (for both ER and PR, P=0.04). The age of patients with tumors containing CA IX-negative fibroblasts was significantly (P=0.002) older than those containing CA IX-positive fibroblasts. The FF diameter/tumor diameter in tumors containing CA IX-positive fibroblasts was significantly larger than those containing CA IX-negative fibroblasts. (3) For the groups of tumor size≤2 cm and tumor size between 2 cm to 5 cm, the diameter of the fibrotic focus was significantly (P<0.01) smaller than the fibrotic focus size of tumors>5 cm in size., Conclusions: CA IX expression is correlated with FF, and that in fibroblasts of FF correlated with patients' age, tumor grade, hormone receptors and FF diameter/tumor diameter. CA IX expression in FF might be a marker for poor prognosis in patients with breast cancer.