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1.
Materials (Basel) ; 17(9)2024 Apr 26.
Article En | MEDLINE | ID: mdl-38730831

Considering the different structural strength requirements of different parts of fiberglass yachts, carbon fiber/glass fiber hybrid reinforcement can be applied to the skins of sandwich panels in special areas. This paper designs and prepares 12 foam sandwich panel samples composed of pure carbon fiber, a carbon fiber/glass fiber hybrid, pure glass fiber skin, and PVC and SAN foam sandwich, with reference to the layup structure of the outer panel of a fiberglass yacht. Through a comparative analysis of low-speed impact experiments, edge compression experiments, and short beam three-point bending experiments, we seek the optimal carbon fiber/glass fiber hybrid layup design scheme for local structures to guide production. The results show that a reasonable hybrid carbon fiber layup in fiberglass skin can effectively reduce the low-speed impact damage of the sandwich structure, reduce edge compression damage, and improve the bending and compression resistance of sandwich structure. The impact resistance, compression resistance, and shear resistance of the SAN sandwich structure are stronger than the PVC sandwich structure. The carbon fiber/glass fiber hybrid SAN foam sandwich structure can be used for the local structural reinforcement of special parts such as the bow, side, and main deck of fiberglass yachts.

2.
Environ Int ; 187: 108649, 2024 May.
Article En | MEDLINE | ID: mdl-38642506

Rapid urbanization in the Asia-Pacific region is expected to place two-thirds of its population in concrete-dominated urban landscapes by 2050. While diverse architectural facades define the unique appearance of these urban systems. There remains a significant gap in our understanding of the composition, assembly, and ecological potential of microbial communities on building exteriors. Here, we examined bacterial and protistan communities on building surfaces along an urbanization gradient (urban, suburban and rural regions), investigating their spatial patterns and the driving factors behind their presence. A total of 55 bacterial and protist phyla were identified. The bacterial community was predominantly composed of Proteobacteria (33.7% to 67.5%). The protistan community exhibited a prevalence of Opisthokonta and Archaeplastida (17.5% to 82.1% and 1.8% to 61.2%, respectively). The composition and functionality of bacterial communities exhibited spatial patterns correlated with urbanization. In urban buildings, factors such as facade type, light exposure, and building height had comparatively less impact on bacterial composition compared to suburban and rural areas. The highest bacterial diversity and lowest Weighted Average Community Identity (WACI) were observed on suburban buildings, followed by rural buildings. In contrast, protists did not show spatial distribution characteristics related to facade type, light exposure, building height and urbanization level. The distinct spatial patterns of protists were primarily shaped by community diffusion and the bottom-up regulation exerted by bacterial communities. Together, our findings suggest that building exteriors serve as attachment points for local microbial metacommunities, offering unique habitats where bacteria and protists exhibit independent adaptive strategies closely tied to the overall ecological potential of the community.


Bacteria , Urbanization , Bacteria/classification , Microbiota
3.
Environ Int ; 187: 108688, 2024 May.
Article En | MEDLINE | ID: mdl-38685158

The phyllosphere, particularly the leaf surface of plants, harbors a diverse range of microbiomes that play a vital role in the functioning of terrestrial ecosystems. However, our understanding of microbial successions and their impact on functional genes during plant community development is limited. In this study, considering core and satellite microbial taxa, we characterized the phyllosphere microbiome and functional genes in various microhabitats (i.e., leaf litter, moss and plant leaves) across the succession of a plant community in a low-altitude glacier foreland. Our findings indicate that phyllosphere microbiomes and associated ecosystem stability increase during the succession of the plant community. The abundance of core taxa increased with plant community succession and was primarily governed by deterministic processes. In contrast, satellite taxa abundance decreased during plant community succession and was mainly governed by stochastic processes. The abundance of microbial functional genes (such as C, N, and P hydrolysis and fixation) in plant leaves generally increased during the plant community succession. However, in leaf litter and moss leaves, only a subset of functional genes (e.g., C fixation and degradation, and P mineralization) showed a tendency to increase with plant community succession. Ultimately, the community of both core and satellite taxa collaboratively influenced the characteristics of phyllosphere nutrient-cycling genes, leading to the diverse profiles and fluctuating abundance of various functional genes during plant community succession. These findings offer valuable insights into the phyllosphere microbiome and plant-microbe interactions during plant community development, advancing our understanding of the succession and functional significance of the phyllosphere microbial community.


Microbiota , Plant Leaves , Plant Leaves/microbiology , Ecosystem , Plants/microbiology , Plant Development
4.
J Phys Chem Lett ; 15(15): 4158-4166, 2024 Apr 18.
Article En | MEDLINE | ID: mdl-38597419

All-inorganic CsPbI2Br perovskite is striking as a result of the reasonable band gap and thermal stability. However, the notorious air instability, unsatisfactory conversion efficiencies, and toxic water-soluble Pb2+ ions have greatly limited the further development of CsPbI2Br-based devices. Herein, a facile strategy is developed to prepare efficient and air-stable CsPbI2Br-based perovskite solar cells (PSCs) with in situ lead leakage protection. With the introduction of 2,2'-dihydroxy-4,4'-dimethoxy-5,5'-disulfobenzophenone disodium salt (BP-9) into the CsPbI2Br precursor solution, the crystallization of perovskite can be regulated at a reduced trap density, the uncoordinated Pb2+ ions and electron-rich defects in the structure can be passivated to suppress non-radiative recombination, and the energy level arrangement can be optimized to improve charge carrier transport. Consequently, the optimized PSC achieved a championship efficiency of 17.11%, accompanied by negligible J-V hysteresis and remarkably improved air stability. More importantly, the strong chelation of BP-9 with water-soluble Pb2+ ions minimizes the leakage of toxic lead in the perovskite structure.

5.
iScience ; 27(3): 109128, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38384835

Visual perceptual learning (VPL), experience-induced gains in discriminating visual features, has been studied extensively and intensively for many years, its profile in feature space, however, remains unclear. Here, human subjects were trained to perform either a simple low-level feature (grating orientation) or a complex high-level object (face view) discrimination task over a long-time course. During, immediately after, and one month after training, all results showed that in feature space VPL in grating orientation discrimination was a center-surround profile; VPL in face view discrimination, however, was a monotonic gradient profile. Importantly, these two profiles can be emerged by a deep convolutional neural network with a modified AlexNet consisted of 7 and 12 layers, respectively. Altogether, our study reveals for the first time a feature hierarchy-dependent profile of VPL in feature space, placing a necessary constraint on our understanding of the neural computation of VPL.

6.
Environ Int ; 185: 108511, 2024 Mar.
Article En | MEDLINE | ID: mdl-38382404

Fungal plant pathogens threaten crop production and sustainable agricultural development. However, the environmental factors driving their diversity and nationwide biogeographic model remain elusive, impacting our capacity to predict their changes under future climate scenarios. Here, we analyzed potential fungal plant pathogens from 563 samples collected from 57 agricultural fields across China. Over 28.0% of fungal taxa in the phyllosphere were identified as potential plant pathogens, compared to 22.3% in the rhizosphere. Dominant fungal plant pathogen groups were Cladosporium (in the phyllosphere) and Fusarium (in the rhizosphere), with higher diversity observed in the phyllosphere than in rhizosphere soil. Deterministic processes played an important role in shaping the potential fungal plant pathogen community assembly in both habitats. Mean annual precipitation and temperature were the most important factor influencing phyllosphere fungal plant pathogen richness. Significantly negative relationships were found between fungal pathogen diversity and sorghum yield. Notably, compared to the rhizosphere, the phyllosphere fungal plant pathogen diversity played a more crucial role in sorghum yield. Together, our work provides novel insights into the factors governing the spatial patterns of fungal plant pathogens in the crop microbiome, and highlights the potential significance of aboveground phyllosphere fungal plant pathogens in crop productivity.


Microbiota , Sorghum , Soil Microbiology , Agriculture , Soil , Edible Grain
7.
J Colloid Interface Sci ; 662: 263-275, 2024 May 15.
Article En | MEDLINE | ID: mdl-38354554

Defect-engineered metal-organic frameworks (DEMOFs) are emerging advanced materials. The construction of DEMOFs is of great significance; however, DEMOF-based catalysis remains unexplored. (E)-vinylboronates, an important building block for asymmetric synthesis, can be synthesized via the hydroboration of alkynes. However, the lack of high-performance catalysts considerably hinders their synthesis. Herein, a series of DEHKUST-1 (HKUST = Hong Kong University of Science and Technology) (Da-f) catalysts with missing occupation of linkers at Cu nodes were designed by partially replacing benzene-1,3,5-tricarboxylate (H3BTC) with defective connectors of pyridine-3,5-dicarboxylate (PYDC) to efficiently promote the hydroboration of alkynes. Results showed that the Dd containing 0.8 doping ratio of PYDC exhibited remarkable catalytic activity than the defect-free HKUST-1. This originated from the improved accessibility for reactants towards the Lewis acid active Cu sites of DEHKUST-1 due to the presence of plenty of rooms next to the Cu sites and enhanced coordination ability in such 'defective' HKUST-1. Dd had high selectivity (>99 %) and yield (>96 %) for (E)-vinylboronates and extensive functional group compatibility for terminal alkynes. Density functional theory (DFT) calculations were performed to elucidate the mechanism of hydroboration. Compared with that of defect-free HKUST-1, the low energy barrier of DEHKUST-1 can be attributed to the lower coordination number of Cu sites and enhanced accessibility of Cu active sites towards reagents.

8.
Psychol Res Behav Manag ; 17: 117-128, 2024.
Article En | MEDLINE | ID: mdl-38223309

Introduction: The general deficit in inhibitory control of problematic social media users has received widespread attention. However, the neural correlates of problematic social media use (PSMU) and inhibitory control remain unclear. Additionally, the co-occurrence of the fear of missing out (FoMO) with social media use is common, yet its role in the relationship between PSMU and inhibitory control has not been investigated. Methods: This study aimed to examine the electrophysiological correlates of PSMU and inhibitory control using a modified two-choice oddball task combined with event-related potentials (ERPs), and to explore the role of FoMO in this relationship. A total of 66 participants with varying degrees of PSMU were included in the analysis based on the Problematic Mobile Social Media Usage Questionnaire. Results: The study found that PSMU could impact inhibitory control. Specifically, as the PSMU score increases, the N2 amplitude is greater for social media-related pictures, and the P3 amplitude is smaller, while no significant differences are observed for neutral pictures. This suggests that PSMU affects inhibitory control by consuming more cognitive resources in the early conflict detection stage and leading to insufficient cognitive resources in the later stages of the inhibitory process. Furthermore, FoMO played a mediating role between PSMU and inhibitory control. PSMU could further impact inhibitory control through FoMO. Conclusion: This study provides electrophysiological evidence for deficits in inhibitory control in PSMU and suggests that FoMO may further reduce inhibitory control in PSMU individuals.

9.
J Hazard Mater ; 465: 133149, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-38056267

The microbiome in the air-phyllosphere-soil continuum of urban greenspaces plays a crucial role in re-connecting urban populations with biodiverse environmental microbiomes. However, little is known about whether plant type affects the airborne microbiomes, as well as the extent to which soil and phyllosphere microbiomes contribute to airborne microbiomes. Here we collected soil, phyllosphere and airborne microbes with different plant types (broadleaf tree, conifer tree, and grass) in urban parks. Despite the significant impacts of plant type on soil and phyllosphere microbiomes, plant type had no obvious effects on the diversity of airborne microbes but shaped airborne bacterial composition in urban greenspaces. Soil and phyllosphere microbiomes had a higher contribution to airborne bacteria in broadleaf trees (37.56%) compared to conifer trees (9.51%) and grasses (14.29%). Grass areas in urban greenspaces exhibited a greater proportion of potential pathogens compared to the tree areas. The abundance of bacterial pathogens in phyllosphere was significantly higher in grasses compared to broadleaf and conifer trees. Together, our study provides novel insights into the microbiome patterns in air-phyllosphere-soil continuum, highlighting the potential significance of reducing the proportion of extensively human-intervened grass areas in future urban environment designs to enhance the provision of ecosystem services in urban greenspaces.


Microbiota , Soil , Humans , Parks, Recreational , Plants , Trees/microbiology , Bacteria , Poaceae
10.
Innovation (Camb) ; 5(1): 100543, 2024 Jan 08.
Article En | MEDLINE | ID: mdl-38111463

Plastic offers a new niche for microorganisms, the plastisphere. The ever-increasing emission of plastic waste makes it critical to understand the microbial ecology of the plastisphere and associated effects. Here, we present a global fingerprint of the plastisphere, analyzing samples collected from freshwater, seawater, and terrestrial ecosystems. The plastisphere assembles a distinct microbial community that has a clearly higher heterogeneity and a more deterministically dominated assembly compared to natural habitats. New coexistence patterns-loose and fragile networks with mostly specialist linkages among microorganisms that are rarely found in natural habitats-are seen in the plastisphere. Plastisphere microbiomes generally have a great potential to metabolize organic compounds, which could accelerate carbon turnover. Microorganisms involved in the nitrogen cycle are also altered in the plastisphere, especially in freshwater plastispheres, where a high abundance of denitrifiers may increase the release of nitrite (aquatic toxicant) and nitrous oxide (greenhouse gas). Enrichment of animal, plant, and human pathogens means that the plastisphere could become an increasingly mobile reservoir of harmful microorganisms. Our findings highlight that if the trajectory of plastic emissions is not reversed, the expanding plastisphere could pose critical planetary health challenges.

11.
ISME J ; 17(12): 2182-2189, 2023 Dec.
Article En | MEDLINE | ID: mdl-37794244

Understanding how antibiotic resistance emerges and evolves in natural habitats is critical for predicting and mitigating antibiotic resistance in the context of global change. Bacteria have evolved antibiotic production as a strategy to fight competitors, predators and other stressors, but how predation pressure of their most important consumers (i.e., protists) affects soil antibiotic resistance genes (ARGs) profiles is still poorly understood. To address this gap, we investigated responses of soil resistome to varying levels of protistan predation by inoculating low, medium and high concentrations of indigenous soil protist suspensions in soil microcosms. We found that an increase in protistan predation pressure was strongly associated with higher abundance and diversity of soil ARGs. High protist concentrations significantly enhanced the abundances of ARGs encoding multidrug (oprJ and ttgB genes) and tetracycline (tetV) efflux pump by 608%, 724% and 3052%, respectively. Additionally, we observed an increase in the abundance of numerous bacterial genera under high protistan pressure. Our findings provide empirical evidence that protistan predation significantly promotes antibiotic resistance in soil bacterial communities and advances our understanding of the biological driving forces behind the evolution and development of environmental antibiotic resistance.


Genes, Bacterial , Soil , Animals , Predatory Behavior , Soil Microbiology , Bacteria/genetics , Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial/genetics , Eukaryota/genetics
12.
Water Res ; 245: 120574, 2023 Oct 15.
Article En | MEDLINE | ID: mdl-37690412

Microplastics (MPs) ubiquitous in environments promote the dissemination of antibiotic resistance genes (ARGs), threatening ecosystem safety and human health. However, quantitative assessments of the health risks of ARGs (HRA) in plastisphere and an in-depth exploration of their driving mechanisms are still lacking. Here, the microbiomes, ARGs, and community assembly processes of five types of MPs in an urbanizing watershed were systematically investigated. By fully considering the abundance, clinical availability, human pathogenicity, human accessibility, and mobility of 660 ARGs in plastisphere, the HRA on MPs were quantified and compared. Polyethylene had the highest HRA among the five MP types, and urbanization further increased its risk index. In addition to abiotic factors, more complex biotic factors have been shown to drive HRA in plastisphere. Specifically, dispersal limitation accounted for the increasing diversity and interaction of bacteria that determined HRA in plastisphere. Further analysis of metabolic functions indicated that a higher HRA was accompanied by decreased normal metabolic functions of plastisphere microbiota due to the higher fitness costs of ARGs. This study advances the quantitative surveillance of HRA in plastisphere and understanding of its driving mechanisms. This will be helpful for the management of both MPs and ARGs treatments for human health.


Genes, Bacterial , Microbiota , Humans , Plastics , Anti-Bacterial Agents , Bacteria/genetics , Microplastics , Microbiota/genetics
13.
Respir Res ; 24(1): 212, 2023 Aug 27.
Article En | MEDLINE | ID: mdl-37635231

BACKGROUND: Previous studies have shown that IL-25 levels are increased in patients with asthma with fixed airflow limitation (FAL). However, the mechanism by which IL-25 contributes to airway remodeling and FAL remains unclear. Here, we hypothesized that IL-25 facilitates pro-fibrotic phenotypic changes in bronchial epithelial cells (BECs) and circulating fibrocytes (CFs), orchestrates pathological crosstalk from BECs to CFs, and thereby contributes to airway remodeling and FAL. METHODS: Fibrocytes from asthmatic patients with FAL and chronic asthma murine models were detected using flow cytometry, multiplex staining and multispectral imaging analysis. The effect of IL-25 on BECs and CFs and on the crosstalk between BECs and CFs was determined using cell culture and co-culture systems. RESULTS: We found that asthmatic patients with FAL had higher numbers of IL-25 receptor (i.e., IL-17RB)+-CFs, which were negatively correlated with forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC). The number of airway IL-17RB+-fibrocytes was significantly increased in ovalbumin (OVA)- and IL-25-induced asthmatic mice versus the control subjects. BECs stimulated with IL-25 exhibited an epithelial-mesenchymal transition (EMT)-like phenotypic changes. CFs stimulated with IL-25 produced high levels of extracellular matrix (ECM) proteins and connective tissue growth factors (CTGF). These profibrotic effects of IL-25 were partially blocked by the PI3K-AKT inhibitor LY294002. In the cell co-culture system, OVA-challenged BECs facilitated the migration and expression of ECM proteins and CTGF in CFs, which were markedly blocked using an anti-IL-17RB antibody. CONCLUSION: These results suggest that IL-25 may serve as a potential therapeutic target for asthmatic patients with FAL.


Airway Remodeling , Asthma , Animals , Mice , Phosphatidylinositol 3-Kinases , Epithelial Cells , Angiogenesis Inhibitors , Extracellular Matrix Proteins
14.
Environ Int ; 179: 108168, 2023 09.
Article En | MEDLINE | ID: mdl-37647704

Rice paddy soil is a hotspot of antibiotic resistance genes (ARGs) due to the application of organic fertilizers. However, the temporal dynamics of ARGs in rice paddy soil and its flooded water during the growing season remain underexplored. In this study, a microcosm experiment was conducted to explore the ARG profiles in a long term (130 days) flooded two-phase manure-amended soil-water system. By using high-throughput quantitative PCR array, a total of 23-98 and 34-85 ARGs were detected in the soil and overlying water, respectively. Regression analysis exhibited significant negative correlations between ARG profile similarities and flooding duration, indicating that flooding significantly altered the resistome (P < 0.001). This finding was validated by the increased ARG abundance in the soil and the overlying water, for example, after 130 days flooding, the abundance of ARGs in CK soil was increased from 0.03 to 1.20 copies per 16S rRNA. The PCoA analysis further suggested pig manure application resulted in distinct ARG profiles in the soil-water continuum compared with those of the non-amended control (Adonis, P < 0.05). The Venn diagram showed that all ARGs detected in the pig manure were present in the treated soil. Twelve ARGs (e.g., sul1) were shared among the pig manure, manure-amended soil, and overlying water, indicating that certain manure- or soil-borne ARGs were readily dispersed from the soil to the overlying water. Moreover, the enhanced relationships between the ARGs and mobile genetic elements in pig manure applied soil-water continuum indicate that the application of organic matter could accelerate the emergence and dissemination of ARGs. These findings suggested that flooding represents a crucial pathway for dispersal of ARGs from the soil to the overlying water. Identification of highly mobile ARGs in the soil-water continuum is essential for assessing their potential risk to human health and promoting the development of sustainable agricultural practices to mitigate their spread.


Oryza , Soil , Humans , Animals , Swine , Manure , RNA, Ribosomal, 16S , Anti-Bacterial Agents , Drug Resistance, Microbial/genetics , Water
15.
Environ Sci Technol ; 57(30): 11267-11278, 2023 08 01.
Article En | MEDLINE | ID: mdl-37477285

The widespread occurrence of tire tread particles (TPs) has aroused increasing concerns over their impacts. However, how they affect the soil fauna remains poorly understood. Here, based on systematically assessing the toxicity of TPs on soil model speciesEnchytraeus crypticusat environmentally relevant concentrations through both soil and food exposure routes, we reported that TPs affected gut microbiota, intestinal histopathology, and metabolites of the worms both through particulate- and leachate-induced effects, while TP leachates exerted stronger effects. The dominant role of TP leachates in TP toxicity was further explained by the findings that worms did not ingest TPs with a particle size of over 150 µm and actively avoided consuming TP particles. Moreover, by comparing the effects of different brands of TPs as well as new and aged TPs, we demonstrated that it was mainly TP leachates that resulted in the ubiquity of the disturbance in the worm's gut microbiota among different brands of TPs. Notably, the large variations in leachate compositions among different brands of TPs provided us a unique opportunity to identify the determinants of TP toxicity. These results provide novel insights into the toxicity of TPs to soil fauna and a reference for toxicity reduction of tires.


Gastrointestinal Microbiome , Dust , Particle Size , Soil
16.
Sci Rep ; 13(1): 7843, 2023 May 15.
Article En | MEDLINE | ID: mdl-37188728

This study investigated the influence of stress levels on the mechanical behavior and particle crushing of irregular granular materials. Granular materials with irregular sides were modelled using the discrete element method. A new method of using a shear fracture zone to characterize the deformation of irregular granular materials under high pressure was proposed. The crushing energy is analysed based on the first law of thermodynamics. The shear strength of irregular granular materials shows significantly nonlinear behavior due to particle crushing. The deformation behavior can be characterized with the help of particle rotation under low confining pressure, and can be characterized with the help of particle breakage under high confining pressure. Granular materials easily break into many single fine particles under high confining pressure. The breakage degree can be represented by the value of crushing energy. Irregular granular materials have a large breakage degree under high confining pressures. It weakens the stability of engineered structures constructed from granular materials.

17.
J Int Med Res ; 51(5): 3000605231173272, 2023 May.
Article En | MEDLINE | ID: mdl-37190764

OBJECTIVE: Septic liver injury is a major burden for the clinical management of sepsis. Hepatocyte cell death plays a crucial pathophysiological role in sepsis. A recent study proposed that NLRP3 inflammasome-mediated pyroptosis participates in septic liver injury. Therefore, investigating the mechanism controlling this process may help manage sepsis. METHODS: We investigated the role of homeodomain-interacting protein kinase 2 (HIPK2) in regulating the NLRP3 inflammasome in vivo using mouse models and in vitro in primary hepatocytes. RESULTS: HIPK2 could improve liver injury and survival in a mouse model of sepsis. Overexpression of HIPK2 could suppress NLRP3 and caspase-1-p20 expression, while HIPK2 knockdown led to higher levels of these two molecules. Importantly, HIPK2 could suppress endoplasmic reticulum (ER) stress. Pharmacologically inhibiting ER stress could abolish activation of the NLRP3 inflammasome in hepatocytes with HIPK2 knockdown. CONCLUSION: HIPK2 can regulate ER stress and NLRP3 inflammasome activation in the liver during sepsis, and HIPK2-mediated suppression of ER stress participates in regulating NLRP3 inflammasome activation. The present study highlights the role of HIPK2 in regulating the inflammasome in septic liver injury, which may serve as a target for managing sepsis.


Inflammasomes , Sepsis , Mice , Animals , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Liver/metabolism , Endoplasmic Reticulum Stress/physiology , Sepsis/genetics , Sepsis/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism
18.
Environ Microbiol Rep ; 15(4): 298-307, 2023 08.
Article En | MEDLINE | ID: mdl-36992636

Protists occupy multiple trophic positions in soil food webs and significantly contribute to organic matter decomposition and biogeochemical cycling. Protists can ingest bacteria and fungi as main food sources while being subjected to predation of invertebrates, but our understanding of how bottom-up and top-down regulations structure protists in natural soil habitats is limited. Here, we disentangle the effects of trophic regulations to the diversity and structure of soil protists in natural settings across northern and eastern Australia. Bacterial and invertebrate diversity were identified as important drivers of the diversity of functional groups of protists. Moreover, the compositions of protistan taxonomic and functional groups were better predicted by bacteria and fungi, than by soil invertebrates. There were strong trophic interconnections between protists and bacteria in multiple organismic network analysis. Altogether, the study provided new evidence that, bottom-up control of bacteria played an important role in shaping the soil protist community structure, which can be derived from feeding preferences of protists on microbial prey, and their intimate relationships in soil functioning or environmental adaptation. Our findings advance our knowledge about the impacts of different trophic groups on key soil organismic communities, with implications for ecosystem functions and services.


Ecosystem , Soil , Eukaryota , Bacteria/genetics , Food Chain , Fungi/genetics , Soil Microbiology
19.
Environ Microbiol ; 25(2): 505-514, 2023 02.
Article En | MEDLINE | ID: mdl-36478095

Soil bacteria are diverse and form complicated ecological networks through various microbial interactions, which play important roles in soil multi-functionality. However, the seasonal effects on the bacterial network, especially the relationship between bacterial network topological features and soil resistomes remains underexplored, which impedes our ability to unveil the mechanisms of the temporal-dynamics of antibiotic resistance genes (ARGs). Here, a field investigation was conducted across four seasons at the watershed scale. We observed significant seasonal variation in bacterial networks, with lower complexity and stability in autumn, and a wider bacterial community niche in summer. Similar to bacterial communities, the co-occurrence networks among ARGs also shift with seasonal change, particularly with respect to the topological features of the node degree, which on average was higher in summer than in the other seasons. Furthermore, the nodes with higher betweenness, stress, degree, and closeness centrality in the bacterial network showed strong relationships with the 10 major classes of ARGs. These findings highlighted the changes in the topological properties of bacterial networks that could further alter antibiotic resistance in soil. Together, our results reveal the temporal dynamics of bacterial ecological networks at the watershed scale, and provide new insights into antibiotic resistance management under environmental changes.


Genes, Bacterial , Soil , Soil Microbiology , Bacteria/genetics , Drug Resistance, Microbial/genetics , Anti-Bacterial Agents/pharmacology
20.
Environ Pollut ; 319: 120900, 2023 Feb 15.
Article En | MEDLINE | ID: mdl-36581242

Organic fertilization is a major contributor to the spread of antibiotic resistance genes (ARGs) in the agroecosystem, which substantially increases the risk of ARGs acquisition and their transmission into human food chains. Earthworms are among the most vital soil faunas involved in the link between belowground and aboveground, and silicon is beneficial for soil health and plant stress resistance. This study aims to explore the effect of different amendment strategies (earthworm and/or silicon) and the related influencing factors on the alleviation of ARGs using high-throughput qPCR. The results showed that the application of earthworms and silicon fertilizers reduced the absolute abundance of ARGs in the rhizosphere soils, either singly or in combination. According to the structural equation model and random forest analysis, mobile genetic elements are the major factors enhancing ARGs transfers and the treatment affects ARGs in direct or indirect ways. Our results highlight the role of "rhizosphere effect" in alleviating antibiotic resistance and suggest that silicon fertilizers, together with the earthworms, can be considered as a sustainable and natural solution to mitigate high-risk ARGs spread in the soil-plant systems. Our findings provide guidance in formulating strategies for halting the spread of ARGs in the agroecosystem.


Brassica , Oligochaeta , Animals , Humans , Anti-Bacterial Agents/pharmacology , Genes, Bacterial , Silicon/pharmacology , Soil/chemistry , Fertilizers/analysis , Manure/analysis , Drug Resistance, Microbial/genetics , Soil Microbiology
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