Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of f...Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.展开更多
Phytoplankton play a pivotal role in the Southern Ocean ecosystem.This study examines the phytoplankton community structure and the environmental factors driving it in the Cosmonaut Sea,based on samples collected usin...Phytoplankton play a pivotal role in the Southern Ocean ecosystem.This study examines the phytoplankton community structure and the environmental factors driving it in the Cosmonaut Sea,based on samples collected using a net during the summer of 2020/2021.We identified 99 phytoplankton species,predominantly comprising diatoms and dinoflagellates.Among these,diatoms-notably Pseudo-nitzschia,Chaetoceros,and Fragilariopsis,dominated the community in terms of species richness,abundance,and biomass.Endemic species of the Southern Ocean,such as Corethron pennatum,Proboscia alata,and Cylindrotheca closterium,also made significant contributions.Phytoplankton abundance and biomass showed similar spatial distribution patterns,with hotspots in the northern section of the survey area that gradually diminished towards the coastal regions.The oceanic area exhibited low phytoplankton diversity but pronounced regional variations in community distribution,with the northern region emerging as a key zone for abundance,biomass,and diversity.Nutrient distribution was identified as the primary environmental driver shaping the phytoplankton community,with silicate levels having a significant negative impact on overall phytoplankton abundance and the dominant species.展开更多
This study analyzed data from zooplankton surveys conducted in the coastal waters of Rizhao during the summers of2020–2023 to deterine trends in the number of taxa,dominant taxa,biomass,abundance,and biodiversity ove...This study analyzed data from zooplankton surveys conducted in the coastal waters of Rizhao during the summers of2020–2023 to deterine trends in the number of taxa,dominant taxa,biomass,abundance,and biodiversity over the 4 years.The results indicated the presence of 41 zooplankton species belonging to Hydromedusa,Ctenophora,Copepoda,Cladocera,Amphipoda,Decapoda,Tunicata,Chaetognatha,Chordata,along with 19 types of planktonic larvae.The total number of taxa showed little change over the 4 years.A total of 10 dominant species and 8 dominant larval types were identified in the surveyed waters,and the dominant species vary from year to year.In terms of community structure,planktonic larvae,hydromedusae,and copepods were the dominant taxa.The proportion of planktonic larvae showed an upward trend,while that of hydromedusae exhibited a downward trend.The zooplankton collected by the shallow water type I(SWI)net and shallow water type II(SWII)net in the survey area could each be divided into 2 communities.Correlation analysis revealed that the abundance of zooplankton collected by the(SWI)net was significantly negatively correlated with water temperature(P<0.05),while the Shannon-Wiener index(H')was significantly positively correlated with water temperature(P<0.05).However,the total number of taxa,abundance,and biomass were significantly higher in the(SWII)net compared to(SWI)net.The average abundance of zooplankton collected in the SWI net gradually decreased over the years(P<0.05).There was no obvious difference in the community diversity indices of zooplankton collected by the two types of nets,and the community structure of zooplankton communities was consistent.展开更多
Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle H...Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.展开更多
Ecological stoichiometry plays an important role in revealing the mechanisms underlying biogeochemical cycles and ecosystem functions.Abiotic factors have strong effects on N-P stoichiometry,yet the impact of plant co...Ecological stoichiometry plays an important role in revealing the mechanisms underlying biogeochemical cycles and ecosystem functions.Abiotic factors have strong effects on N-P stoichiometry,yet the impact of plant community structure,especially in forests,has not been fully elucidated.We investigated 68 plots in larch forests in northern China to explore how plant community structure and environmental factors affect the N-P stoichiometry of soil and leaves.The results showed significant differences in soil and leaf N-P stoichiometry among the three larch forests,P concentration and N:P ratio of leaves were significantly related to those of soil.Except for larch forest type,N-P stoichiometry was also regulated by elevation,climatic factors,and community structure.With increasing age(from 25 to 236 years),soil N and N:P ratio significantly increased,especially in the topsoil.With increasing mean DBH,leaf N concentration and N:P ratio also increased,indicating a shift in nutrient limitations with stand growth.These findings provide evidence that plant community structure and environmental factors regulate soil and leaf N-P stoichiometry,which is critically important for understanding biogeochemical cycles and forest management undergoing natural succession.展开更多
Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated...Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.展开更多
Dynamic publishing of social network graphs offers insights into user behavior but brings privacy risks, notably re-identification attacks on evolving data snapshots. Existing methods based on -anonymity can mitigate ...Dynamic publishing of social network graphs offers insights into user behavior but brings privacy risks, notably re-identification attacks on evolving data snapshots. Existing methods based on -anonymity can mitigate these attacks but are cumbersome, neglect dynamic protection of community structure, and lack precise utility measures. To address these challenges, we present a dynamic social network graph anonymity scheme with community structure protection (DSNGA-CSP), which achieves the dynamic anonymization process by incorporating community detection. First, DSNGA-CSP categorizes communities of the original graph into three types at each timestamp, and only partitions community subgraphs for a specific category at each updated timestamp. Then, DSNGA-CSP achieves intra-community and inter-community anonymization separately to retain more of the community structure of the original graph at each timestamp. It anonymizes community subgraphs by the proposed novel -composition method and anonymizes inter-community edges by edge isomorphism. Finally, a novel information loss metric is introduced in DSNGA-CSP to precisely capture the utility of the anonymized graph through original information preservation and anonymous information changes. Extensive experiments conducted on five real-world datasets demonstrate that DSNGA-CSP consistently outperforms existing methods, providing a more effective balance between privacy and utility. Specifically, DSNGA-CSP shows an average utility improvement of approximately 30% compared to TAKG and CTKGA for three dynamic graph datasets, according to the proposed information loss metric IL.展开更多
Macrobenthos can serve as an indicator of hypoxia in the estuarine ecosystem.This comparative study surveyed macrobenthos from hypoxic and non-hypoxic areas of the Zhujiang(Pearl)River Estuary(PRE),and explores the ef...Macrobenthos can serve as an indicator of hypoxia in the estuarine ecosystem.This comparative study surveyed macrobenthos from hypoxic and non-hypoxic areas of the Zhujiang(Pearl)River Estuary(PRE),and explores the effects of environmental factor on the macrobenthos community structure.In July 2020,49 macrobenthos species were collected from the hypoxic area,contrasting with 91 species found in the non-hypoxic area.July 2021 recorded 51 species in the hypoxic area and 76 in the non-hypoxic area.Analysis of similarities(ANOSIM)and non-metric multidimentional scaling(NMDS)showed no significant difference in the macrobenthos community structure between the two areas.However,Polychaeta displays higher species richness,abundance,and biomass in the hypoxic zone,negatively correlating to dissolved oxygen(DO).Canonical correspondence analysis(CCA)also showed that the abundance of Polychaeta was negatively correlated with that of Crustacea.Interestingly,despite the differences in Polychaeta,macrobenthos community structure remains stable between hypoxic and non-hypoxic samples.This study suggests Polychaeta’s potential adaptation to hypoxic conditions in the PRE’s hypoxic area.Finally,Spearman correlation analysis showed that DO have a significant negative correlation with total phosphorus(TP),total nitrogen(TN)and total organic carbon(TOC)in the PRE,indicating that water eutrophication would exacerbate the occurrence of hypoxia.展开更多
Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River—which is the longest river in China.As phytoplankton are sensitive indicators of trophic changes inwater bodies,characterizing...Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River—which is the longest river in China.As phytoplankton are sensitive indicators of trophic changes inwater bodies,characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution control.Here,we used direct microscopic count and environmental DNA(eDNA)metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin(Chengdu,Sichuan Province,China).The association between phytoplankton community structure and water environmental factors was evaluated by Mantel analysis.Additional environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation modeling.At the phylum level,the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta,Chlorophyta,and Cyanophyta,in contrast with Chlorophyta,Dinophyceae,and Bacillariophyta identified by eDNA metabarcoding.Inα-diversity analysis,eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic method.Phytoplankton growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios>16:1 in all water samples.Redundancy analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton growth.The results could be useful for implementing comprehensive management of the river basin environment.It is recommended to control the discharge of point-and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients(e.g.,Jianyang-Ziyang).Algae monitoring techniques and removal strategies should be improved in 201 Hospital,Hongrihe Bridge and Colmar Town areas.展开更多
Habitat loss driven by land-use change is a major factor shaping the dynamics of urban bird community structures.However,the potential mechanisms by which the spatial configuration and composition of blue-green infras...Habitat loss driven by land-use change is a major factor shaping the dynamics of urban bird community structures.However,the potential mechanisms by which the spatial configuration and composition of blue-green infrastructure,recognized as biodiversity hotspots in urban landscapes,influence urban bird beta diversity remain insufficiently understood.This study was conducted in the built-up area of Yinchuan,an internationally recognized wetland city in Northwest China.From December 2023 to June 2024,we systematically surveyed bird communities during both the breeding and wintering periods across 29 blue-green space mosaics.We quantified taxonomic,functional,and phylogenetic beta diversity,along with their turnover component and nestedness-resultant component,based on both pairwise beta diversity and multiple-site beta diversity.We further assessed the relative importance of landscape variables and spatial geographic distance in shaping beta diversity patterns and used hierarchical modeling of species communities(HMSC)to explore the responses of bird occurrence and functional traits to landscape variables.Our results revealed that species turnover was the dominant driver of taxonomic,functional,and phylogenetic beta diversity.Seasonal differences were observed in the effects of spatial geographic distance and landscape structure on beta diversity and its components,with landscape variables showing higher explanatory power than geographic isolation.In the breeding period,landscape diversity and waterbody area had positive effects on bird occurrence,whereas in the wintering period,most landscape features—except for landscape diversity—exerted neutral or negative influences.Regarding functional traits,we found that reproductive traits,flight ability,and foraging characteristics responded significantly to landscape structure,and that some small-bodied species active in aerial and canopy layers were more adaptable to habitat fragmentation.This study provides novel insights into the assembly processes and driving mechanisms of urban bird communities and offers scientific support for the notion that designing and maintaining blue-green infrastructure can contribute to urban biodiversity conservation.展开更多
Understanding microbial responses to polycyclic aromatic hydrocarbon(PAH)pollution is crucial for assessing the current status of PAH contamination in polar regions.In this study,intertidal and marine sediments were e...Understanding microbial responses to polycyclic aromatic hydrocarbon(PAH)pollution is crucial for assessing the current status of PAH contamination in polar regions.In this study,intertidal and marine sediments were enriched with a mixture of PAHs(naphthalene,phenanthrene,fluorene,pyrene,and fluoranthene).Isolation of culturable bacteria,high-throughput sequencing,and functional prediction were combined to systematically analyze bacterial structural and predicted functional responses to PAH exposure.High-throughput sequencing results showed that the relative abundance of Proteobacteria was significantly increased after enrichment,and Pseudomonas and Acinetobacter were identified as dominant genera under PAH exposure.These findings were consistent with the 19 potential PAH-degrading strains(mainly Pseudomonas)that were successfully isolated from enrichment cultures.Distinct bacterial taxa between enriched marine and intertidal sediments indicated the existence of distinct PAH-degrading groups.PICRUSt2-based functional predictions suggested higher predicted abundances of PAH-degradation pathways in polar sediments,likely through the preferential degradation of parent PAH compounds in response to elevated concentrations.This study provides valuable data on microbial responses to PAH pollution in polar regions and offers new insights for evaluating ecological hazards induced by PAHs.展开更多
The increasing incidence of global warming and frequent heavy precipitation events presents a significant challenge for urban areas in managing extreme precipitation.Strengthening the resilience of communities to clim...The increasing incidence of global warming and frequent heavy precipitation events presents a significant challenge for urban areas in managing extreme precipitation.Strengthening the resilience of communities to climate change is a crucial strategy for fostering sustainable urban development.Green infrastructure offers an ecologically system for rainwater management and ecological restoration,and plays a significant role in adapting to climate risks.This study focuses on climate resilience by examining the implementation of green rainwater infrastructure within the context of climate-adapted green infrastructure in the High Point community of Seattle,USA,and proposes renewal planning strategies,methods,and implementation concepts at the community level.The research indicates that the High Point community has effectively mitigated the issue of waterlogging and enhanced the local microclimate through the implementation of green infrastructure systems,including permeable pavement,rain gardens,bioretention pools,and vegetative buffer zones.It is proposed that the collaborative design of green infrastructure should adhere to principles of systematization,alignment with natural processes,adaptation to the local environment,and engagement of multiple stakeholders,while considering various functions,diverse communities,and differing social contexts.Furthermore,it should be developed in consideration of the unique spatial characteristics,landscape structures,and social needs of each community.展开更多
The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and or...The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.Here,land-use types in the agro-pastoral ecotone,including shrubland(BF),artificial grassland(ArG),abandoned grassland(AbG),and maize farmland(MA),were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter(DOM)composition.The results showed that compared to MA,the macroaggregates in BF,AbG,and ArG were increased by 123.0,92.79,and 63.71%,respectively,while MA soil had the greatest abundance of<100μm particles.The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level(12.61 g kg^(-1)),while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon,so it is prone to loss from the active carbon pools.The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria,Actinobacteriota,Chloroflexi,and Ascomycota.More taxonomic groups from phylum to family were enriched in BF soil.The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities,jointly explaining 61.66% of the variance,while aggregates are important variables driving the composition of fungal communities,with an explanation rate of 20.49%.Our results suggest that DOM components and aggregates impact the soil microbial structure;and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability,carbon sequestration potential,and microbial diversity.展开更多
Diversity of soil microorganisms in different habitats of arid and semi-arid areas plays an important role in the soil texture and nutrient,promoting the growth of vegetation in those areas.To clarify the response of ...Diversity of soil microorganisms in different habitats of arid and semi-arid areas plays an important role in the soil texture and nutrient,promoting the growth of vegetation in those areas.To clarify the response of soil bacterial community diversity to the changes of environmental factors in different habitats,this study collected soil samples under the canopies of Tamarix ramosissima Ledeb.in oasis,transition zone,and desert habitats in the upper reaches of the Tarim River,Northwest China.High-throughput sequencing technology and PICRUSt2 software were used to explore the composition and function of soil bacterial communities in different habitats of T.ramosissima.The results showed that:(1)soil environmental factors under the canopy of T.ramosissima in the three habitats differed significantly,with soil moisture and nutrient conditions being better in the oasis;(2)Proteobacteria,Bacteroidetes,Firmicutes,Actinobacteria,and Gemmatimonadetes were the major bacterial communities in the three habitats;(3)soil bacterial community composition under the canopy of T.ramosissima varied greatly,and the richness was significantly different among the three habitats;(4)redundancy analysis indicated that soil water content and available phosphorous were the most important environmental factors influencing the composition of soil bacterial community;and(5)6 primary functions and 21 secondary functions were obtained by PICRUSt2 function prediction,with metabolism being the most dominant function.This study revealed the response of soil bacterial community composition to habitat changes and their driving factors in the upper reaches of the Tarim River,which could improve the understanding of ecological sensitivity of soil microorganisms in arid and semi-arid areas,and provide a theoretical foundation for improving soil quality and ecological protection.展开更多
Manure slurry application to farmland reduces chemical fertilizer use,mitigates pollution,and improves soil fertility.However,researches on the role of anaerobically treated cow slurry applied to soil microorganisms i...Manure slurry application to farmland reduces chemical fertilizer use,mitigates pollution,and improves soil fertility.However,researches on the role of anaerobically treated cow slurry applied to soil microorganisms in Northeast China remain underexplored.Here,in laboratory incubation experiments,different treatments including various combinations of sterilized and non-sterilized soil and slurry,and different application rates were employed to examine the effects of indigenous microorganisms on soil microbial communities.Field-collected soil samples were employed to examine the responses and spatial variations of soil microbes under production conditions.The results indicated that indigenous soil microorganisms exerted a dominant influence in the microbial community variations,while the impact of cow slurry microbiota on community diversity was relatively minor.At the phylum level,Proteobacteria(P=0.031,R=0.969)showed a significant positive correlation with the slurry application,whereas Acidobacteriota(P=0.012,R=–0.988)and Basidiomycota(P=0.01,R=–0.99)showed significant negative correlations.In the field environment,the autumn slurry application effects on soil microbes in the following year were not significant.In contrast,under spring slurry application,the cow slurry-soil agglomerations led to significant spatial differences in soil microbial communities,with higher microbial diversity observed in the vicinity of agglomerations.The microbes in agglomerations,such as Actinomycetes,Bacteroides and Proteobacteria,were found to be beneficial for the crop residue decomposition.These microorganisms could decompose organic compounds including lignin,cellulose,hemicellulose,and xylan in crop straw.Overall,slurry application indeed influenced soil microbes and induced spatial variations,providing insights for sustainable agricultural practices.展开更多
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'...Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.展开更多
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented...In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.展开更多
Conformal truss-like lattice structures face significant manufacturability challenges in additive manufac-turing due to overhang angle limitations.To address this problem,we propose a novel angle-constrained optimizat...Conformal truss-like lattice structures face significant manufacturability challenges in additive manufac-turing due to overhang angle limitations.To address this problem,we propose a novel angle-constrained optimization method grounded in the global adjustment of nodal coordinates.First,a build direction is selected to minimize the number of violating struts.Then,an angular-constraint matrix is assembled from strut direction vectors,and analytical sensitivities with respect to nodal coordinates are derived to enable efficient constrained optimization under nonlinear angular inequality constraints.Numerical studies on two complex curved-surface lattices demonstrate that all overhang violations are eliminated while only minor changes are induced in global stiffness and strength.In particular,the maximum displacement of an ergonomic insole varies by only 2.87%after optimization.The results confirm the method’s versatility and engineering robustness,providing a practical approach for additive manufacturing-oriented lattice structure design.展开更多
On the occasion of the 65th anniversary of the establishment of diplomatic relations between China and Laos,I wish to express,on behalf of the Embassy of the People's Republic of China in the Lao People's Demo...On the occasion of the 65th anniversary of the establishment of diplomatic relations between China and Laos,I wish to express,on behalf of the Embassy of the People's Republic of China in the Lao People's Democratic Republic,our sincere gratitude and highest respect to all friends and personages from various sectors in both countries who have long cared about and supported the development of our bilateral relations.展开更多
Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structu...Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structural rigidity and flexibility,ensuring material integrity during large deformations,and providing adequate load-bearing capacity and stability once deployed.Most research has focused on optimizing cutout size and shape,while topology optimization offers a broader design space.However,the anisotropic properties of woven composite laminates,complex failure criteria,and multi-performance optimization needs have limited the exploration of topology optimization in this field.This work derives the sensitivities of bending stiffness,critical buckling load,and the failure index of woven composite materials with respect to element density,and formulates both single-objective and multi-objective topology optimization models using a linear weighted aggregation approach.The developed method was integrated with the commercial finite element software ABAQUS via a Python script,allowing efficient application to cutout design in various DCTWS configurations to maximize bending stiffness and critical buckling load under material failure constraints.Optimization of a classical tubular hinge resulted in improvements of 107.7%in bending stiffness and 420.5%in critical buckling load compared to level-set topology optimization results reported in the literature,validating the effectiveness of the approach.To facilitate future research and encourage the broader adoption of topology optimization techniques in DCTWS design,the source code for this work is made publicly available via a Git Hub link:https://github.com/jinhao-ok1/Topo-for-DCTWS.git.展开更多
基金supported by the Zhejiang Provincial Natural Science Foundation,China(Grant No.LQ24C010007)Zhejiang Science and Technology Major Program on Rice New Variety Breeding,China(Grant No.2021C02063)+4 种基金the Agricultural Sciences and Technologies Innovation Program,China(Grant No.CAAS-CSCB-202301)the Key Projects of Zhejiang Provincial Natural Science Foundation,China(Grant No.LZ23C130002)the Youth Innovation Program of Chinese Academy of Agricultural Sciences(Grant No.Y2023QC22)the Joint Open Competitive Project of the Yazhou Bay Seed Laboratory and China National Seed Company Limited(Grant Nos.B23YQ1514 and B23CQ15EP)the External Cooperation Projects of Biotechnology Research Institute,Fujian Academy of Agricultural Sciences,China(Grant No.DWHZ2024-07).
文摘Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.
基金funded by National Science Foundation of China(Grant no.42276238)Impact and Response of Antarctic Seas to Climate Change(Grant nos.IRASCC 01-02-01D,01-01-02A)Taishan Scholars Program.
文摘Phytoplankton play a pivotal role in the Southern Ocean ecosystem.This study examines the phytoplankton community structure and the environmental factors driving it in the Cosmonaut Sea,based on samples collected using a net during the summer of 2020/2021.We identified 99 phytoplankton species,predominantly comprising diatoms and dinoflagellates.Among these,diatoms-notably Pseudo-nitzschia,Chaetoceros,and Fragilariopsis,dominated the community in terms of species richness,abundance,and biomass.Endemic species of the Southern Ocean,such as Corethron pennatum,Proboscia alata,and Cylindrotheca closterium,also made significant contributions.Phytoplankton abundance and biomass showed similar spatial distribution patterns,with hotspots in the northern section of the survey area that gradually diminished towards the coastal regions.The oceanic area exhibited low phytoplankton diversity but pronounced regional variations in community distribution,with the northern region emerging as a key zone for abundance,biomass,and diversity.Nutrient distribution was identified as the primary environmental driver shaping the phytoplankton community,with silicate levels having a significant negative impact on overall phytoplankton abundance and the dominant species.
基金the Open Fund of Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation(No.202309)the Science and Technology Program of the North China Sea Bureau of the Ministry of Natural Resources(No.202302)。
文摘This study analyzed data from zooplankton surveys conducted in the coastal waters of Rizhao during the summers of2020–2023 to deterine trends in the number of taxa,dominant taxa,biomass,abundance,and biodiversity over the 4 years.The results indicated the presence of 41 zooplankton species belonging to Hydromedusa,Ctenophora,Copepoda,Cladocera,Amphipoda,Decapoda,Tunicata,Chaetognatha,Chordata,along with 19 types of planktonic larvae.The total number of taxa showed little change over the 4 years.A total of 10 dominant species and 8 dominant larval types were identified in the surveyed waters,and the dominant species vary from year to year.In terms of community structure,planktonic larvae,hydromedusae,and copepods were the dominant taxa.The proportion of planktonic larvae showed an upward trend,while that of hydromedusae exhibited a downward trend.The zooplankton collected by the shallow water type I(SWI)net and shallow water type II(SWII)net in the survey area could each be divided into 2 communities.Correlation analysis revealed that the abundance of zooplankton collected by the(SWI)net was significantly negatively correlated with water temperature(P<0.05),while the Shannon-Wiener index(H')was significantly positively correlated with water temperature(P<0.05).However,the total number of taxa,abundance,and biomass were significantly higher in the(SWII)net compared to(SWI)net.The average abundance of zooplankton collected in the SWI net gradually decreased over the years(P<0.05).There was no obvious difference in the community diversity indices of zooplankton collected by the two types of nets,and the community structure of zooplankton communities was consistent.
基金The National Natural Science Foundation of China under contract Nos 42206126 and 42076044the Natural Science Foundation of Shandong Province under contract No.ZR2021QD099.
文摘Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.
基金supported by the National Natural Science Foundation of China(No.32201426,No.31988102)the Major Program for Basic Research Project of Yunnan Province(No.202101BC070002)the Key Research and Development Program of Yunnan Provin ce(No.202303AC100009).
文摘Ecological stoichiometry plays an important role in revealing the mechanisms underlying biogeochemical cycles and ecosystem functions.Abiotic factors have strong effects on N-P stoichiometry,yet the impact of plant community structure,especially in forests,has not been fully elucidated.We investigated 68 plots in larch forests in northern China to explore how plant community structure and environmental factors affect the N-P stoichiometry of soil and leaves.The results showed significant differences in soil and leaf N-P stoichiometry among the three larch forests,P concentration and N:P ratio of leaves were significantly related to those of soil.Except for larch forest type,N-P stoichiometry was also regulated by elevation,climatic factors,and community structure.With increasing age(from 25 to 236 years),soil N and N:P ratio significantly increased,especially in the topsoil.With increasing mean DBH,leaf N concentration and N:P ratio also increased,indicating a shift in nutrient limitations with stand growth.These findings provide evidence that plant community structure and environmental factors regulate soil and leaf N-P stoichiometry,which is critically important for understanding biogeochemical cycles and forest management undergoing natural succession.
基金supported by the National Key Research and Development Project of China(No.2021YFB2600200)the National Natural Science Foundation of China(Nos.52470185 and 52170159)the Open Research Fund of National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,the Fund of National Key Laboratory of Water Disaster Prevention and Key Research and Development Program of Jiangsu Province(No.BE2022601).
文摘Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.
基金supported by the Natural Science Foundation of China(No.U22A2099)the Innovation Project of Guangxi Graduate Education(YCBZ2023130).
文摘Dynamic publishing of social network graphs offers insights into user behavior but brings privacy risks, notably re-identification attacks on evolving data snapshots. Existing methods based on -anonymity can mitigate these attacks but are cumbersome, neglect dynamic protection of community structure, and lack precise utility measures. To address these challenges, we present a dynamic social network graph anonymity scheme with community structure protection (DSNGA-CSP), which achieves the dynamic anonymization process by incorporating community detection. First, DSNGA-CSP categorizes communities of the original graph into three types at each timestamp, and only partitions community subgraphs for a specific category at each updated timestamp. Then, DSNGA-CSP achieves intra-community and inter-community anonymization separately to retain more of the community structure of the original graph at each timestamp. It anonymizes community subgraphs by the proposed novel -composition method and anonymizes inter-community edges by edge isomorphism. Finally, a novel information loss metric is introduced in DSNGA-CSP to precisely capture the utility of the anonymized graph through original information preservation and anonymous information changes. Extensive experiments conducted on five real-world datasets demonstrate that DSNGA-CSP consistently outperforms existing methods, providing a more effective balance between privacy and utility. Specifically, DSNGA-CSP shows an average utility improvement of approximately 30% compared to TAKG and CTKGA for three dynamic graph datasets, according to the proposed information loss metric IL.
基金The Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)under contract No.311021004the Biodiversity Assessment of Key Marine Habitat in China under contract Nos PM-zx555-202107-208 and PM-zx555-202106-195.
文摘Macrobenthos can serve as an indicator of hypoxia in the estuarine ecosystem.This comparative study surveyed macrobenthos from hypoxic and non-hypoxic areas of the Zhujiang(Pearl)River Estuary(PRE),and explores the effects of environmental factor on the macrobenthos community structure.In July 2020,49 macrobenthos species were collected from the hypoxic area,contrasting with 91 species found in the non-hypoxic area.July 2021 recorded 51 species in the hypoxic area and 76 in the non-hypoxic area.Analysis of similarities(ANOSIM)and non-metric multidimentional scaling(NMDS)showed no significant difference in the macrobenthos community structure between the two areas.However,Polychaeta displays higher species richness,abundance,and biomass in the hypoxic zone,negatively correlating to dissolved oxygen(DO).Canonical correspondence analysis(CCA)also showed that the abundance of Polychaeta was negatively correlated with that of Crustacea.Interestingly,despite the differences in Polychaeta,macrobenthos community structure remains stable between hypoxic and non-hypoxic samples.This study suggests Polychaeta’s potential adaptation to hypoxic conditions in the PRE’s hypoxic area.Finally,Spearman correlation analysis showed that DO have a significant negative correlation with total phosphorus(TP),total nitrogen(TN)and total organic carbon(TOC)in the PRE,indicating that water eutrophication would exacerbate the occurrence of hypoxia.
基金supported by the National Natural Science Foundation of China (No.72091511)the Science Fund for Distinguished Young Scholars of Hebei Province (No.E2022402064).
文摘Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River—which is the longest river in China.As phytoplankton are sensitive indicators of trophic changes inwater bodies,characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution control.Here,we used direct microscopic count and environmental DNA(eDNA)metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin(Chengdu,Sichuan Province,China).The association between phytoplankton community structure and water environmental factors was evaluated by Mantel analysis.Additional environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation modeling.At the phylum level,the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta,Chlorophyta,and Cyanophyta,in contrast with Chlorophyta,Dinophyceae,and Bacillariophyta identified by eDNA metabarcoding.Inα-diversity analysis,eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic method.Phytoplankton growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios>16:1 in all water samples.Redundancy analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton growth.The results could be useful for implementing comprehensive management of the river basin environment.It is recommended to control the discharge of point-and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients(e.g.,Jianyang-Ziyang).Algae monitoring techniques and removal strategies should be improved in 201 Hospital,Hongrihe Bridge and Colmar Town areas.
基金supported by the National Natural Science Foundation of China(32401409)the Central Government’s Special Fund for National Key Protected Wildlife Conservation Projects in Yinchuan City(HXCG-ZC2023148,XZ-2024-16)。
文摘Habitat loss driven by land-use change is a major factor shaping the dynamics of urban bird community structures.However,the potential mechanisms by which the spatial configuration and composition of blue-green infrastructure,recognized as biodiversity hotspots in urban landscapes,influence urban bird beta diversity remain insufficiently understood.This study was conducted in the built-up area of Yinchuan,an internationally recognized wetland city in Northwest China.From December 2023 to June 2024,we systematically surveyed bird communities during both the breeding and wintering periods across 29 blue-green space mosaics.We quantified taxonomic,functional,and phylogenetic beta diversity,along with their turnover component and nestedness-resultant component,based on both pairwise beta diversity and multiple-site beta diversity.We further assessed the relative importance of landscape variables and spatial geographic distance in shaping beta diversity patterns and used hierarchical modeling of species communities(HMSC)to explore the responses of bird occurrence and functional traits to landscape variables.Our results revealed that species turnover was the dominant driver of taxonomic,functional,and phylogenetic beta diversity.Seasonal differences were observed in the effects of spatial geographic distance and landscape structure on beta diversity and its components,with landscape variables showing higher explanatory power than geographic isolation.In the breeding period,landscape diversity and waterbody area had positive effects on bird occurrence,whereas in the wintering period,most landscape features—except for landscape diversity—exerted neutral or negative influences.Regarding functional traits,we found that reproductive traits,flight ability,and foraging characteristics responded significantly to landscape structure,and that some small-bodied species active in aerial and canopy layers were more adaptable to habitat fragmentation.This study provides novel insights into the assembly processes and driving mechanisms of urban bird communities and offers scientific support for the notion that designing and maintaining blue-green infrastructure can contribute to urban biodiversity conservation.
基金supported by the project from the National Natural Science Foundation of China(Grant no.42230411)the Science&Technology Innovation Project of Laoshan Laboratory(Grant no.LSKJ202203206)。
文摘Understanding microbial responses to polycyclic aromatic hydrocarbon(PAH)pollution is crucial for assessing the current status of PAH contamination in polar regions.In this study,intertidal and marine sediments were enriched with a mixture of PAHs(naphthalene,phenanthrene,fluorene,pyrene,and fluoranthene).Isolation of culturable bacteria,high-throughput sequencing,and functional prediction were combined to systematically analyze bacterial structural and predicted functional responses to PAH exposure.High-throughput sequencing results showed that the relative abundance of Proteobacteria was significantly increased after enrichment,and Pseudomonas and Acinetobacter were identified as dominant genera under PAH exposure.These findings were consistent with the 19 potential PAH-degrading strains(mainly Pseudomonas)that were successfully isolated from enrichment cultures.Distinct bacterial taxa between enriched marine and intertidal sediments indicated the existence of distinct PAH-degrading groups.PICRUSt2-based functional predictions suggested higher predicted abundances of PAH-degradation pathways in polar sediments,likely through the preferential degradation of parent PAH compounds in response to elevated concentrations.This study provides valuable data on microbial responses to PAH pollution in polar regions and offers new insights for evaluating ecological hazards induced by PAHs.
文摘The increasing incidence of global warming and frequent heavy precipitation events presents a significant challenge for urban areas in managing extreme precipitation.Strengthening the resilience of communities to climate change is a crucial strategy for fostering sustainable urban development.Green infrastructure offers an ecologically system for rainwater management and ecological restoration,and plays a significant role in adapting to climate risks.This study focuses on climate resilience by examining the implementation of green rainwater infrastructure within the context of climate-adapted green infrastructure in the High Point community of Seattle,USA,and proposes renewal planning strategies,methods,and implementation concepts at the community level.The research indicates that the High Point community has effectively mitigated the issue of waterlogging and enhanced the local microclimate through the implementation of green infrastructure systems,including permeable pavement,rain gardens,bioretention pools,and vegetative buffer zones.It is proposed that the collaborative design of green infrastructure should adhere to principles of systematization,alignment with natural processes,adaptation to the local environment,and engagement of multiple stakeholders,while considering various functions,diverse communities,and differing social contexts.Furthermore,it should be developed in consideration of the unique spatial characteristics,landscape structures,and social needs of each community.
基金funded by the Inner Mongolia Local Science and Technology Development Fund Projects,China(2021GG0393)。
文摘The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.Here,land-use types in the agro-pastoral ecotone,including shrubland(BF),artificial grassland(ArG),abandoned grassland(AbG),and maize farmland(MA),were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter(DOM)composition.The results showed that compared to MA,the macroaggregates in BF,AbG,and ArG were increased by 123.0,92.79,and 63.71%,respectively,while MA soil had the greatest abundance of<100μm particles.The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level(12.61 g kg^(-1)),while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon,so it is prone to loss from the active carbon pools.The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria,Actinobacteriota,Chloroflexi,and Ascomycota.More taxonomic groups from phylum to family were enriched in BF soil.The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities,jointly explaining 61.66% of the variance,while aggregates are important variables driving the composition of fungal communities,with an explanation rate of 20.49%.Our results suggest that DOM components and aggregates impact the soil microbial structure;and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability,carbon sequestration potential,and microbial diversity.
基金supported by the Sciences Foundation of Xinjiang Uygur Autonomous Region(2024D01C32)the Xinjiang Uygur Autonomous Region Education Department Basic Scientific Project(XJEDU2023P005)+1 种基金the National Natural Science Foundation of China(32001145)the 2024 Xinjiang Uygur Autonomous Region Postdoctoral Funding Project.
文摘Diversity of soil microorganisms in different habitats of arid and semi-arid areas plays an important role in the soil texture and nutrient,promoting the growth of vegetation in those areas.To clarify the response of soil bacterial community diversity to the changes of environmental factors in different habitats,this study collected soil samples under the canopies of Tamarix ramosissima Ledeb.in oasis,transition zone,and desert habitats in the upper reaches of the Tarim River,Northwest China.High-throughput sequencing technology and PICRUSt2 software were used to explore the composition and function of soil bacterial communities in different habitats of T.ramosissima.The results showed that:(1)soil environmental factors under the canopy of T.ramosissima in the three habitats differed significantly,with soil moisture and nutrient conditions being better in the oasis;(2)Proteobacteria,Bacteroidetes,Firmicutes,Actinobacteria,and Gemmatimonadetes were the major bacterial communities in the three habitats;(3)soil bacterial community composition under the canopy of T.ramosissima varied greatly,and the richness was significantly different among the three habitats;(4)redundancy analysis indicated that soil water content and available phosphorous were the most important environmental factors influencing the composition of soil bacterial community;and(5)6 primary functions and 21 secondary functions were obtained by PICRUSt2 function prediction,with metabolism being the most dominant function.This study revealed the response of soil bacterial community composition to habitat changes and their driving factors in the upper reaches of the Tarim River,which could improve the understanding of ecological sensitivity of soil microorganisms in arid and semi-arid areas,and provide a theoretical foundation for improving soil quality and ecological protection.
基金Supported by the China Postdoctoral Science Foundation(2021M700742)Heilongjiang Postdoctoral Fund(LBH–Z21109)。
文摘Manure slurry application to farmland reduces chemical fertilizer use,mitigates pollution,and improves soil fertility.However,researches on the role of anaerobically treated cow slurry applied to soil microorganisms in Northeast China remain underexplored.Here,in laboratory incubation experiments,different treatments including various combinations of sterilized and non-sterilized soil and slurry,and different application rates were employed to examine the effects of indigenous microorganisms on soil microbial communities.Field-collected soil samples were employed to examine the responses and spatial variations of soil microbes under production conditions.The results indicated that indigenous soil microorganisms exerted a dominant influence in the microbial community variations,while the impact of cow slurry microbiota on community diversity was relatively minor.At the phylum level,Proteobacteria(P=0.031,R=0.969)showed a significant positive correlation with the slurry application,whereas Acidobacteriota(P=0.012,R=–0.988)and Basidiomycota(P=0.01,R=–0.99)showed significant negative correlations.In the field environment,the autumn slurry application effects on soil microbes in the following year were not significant.In contrast,under spring slurry application,the cow slurry-soil agglomerations led to significant spatial differences in soil microbial communities,with higher microbial diversity observed in the vicinity of agglomerations.The microbes in agglomerations,such as Actinomycetes,Bacteroides and Proteobacteria,were found to be beneficial for the crop residue decomposition.These microorganisms could decompose organic compounds including lignin,cellulose,hemicellulose,and xylan in crop straw.Overall,slurry application indeed influenced soil microbes and induced spatial variations,providing insights for sustainable agricultural practices.
文摘Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.
基金Supported by the National Key Research and Development Program of Traditional Chinese Medicine Modernization Project,China(No.2023YFC3504000)the Science and Technology Development Project of Jilin Province,China(No.20240404043ZP)the Science and Technology Innovation Cooperation Project of Changchun Science and Technology Bureau and Chinese Academy of Sciences,China(No.23SH14)。
文摘In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.
基金supported by the National Natural Science Foundation of China(Grant Nos.12432005 and 12472116)the Fundamental Research Funds for the Central Universities(DUTZD25240).
文摘Conformal truss-like lattice structures face significant manufacturability challenges in additive manufac-turing due to overhang angle limitations.To address this problem,we propose a novel angle-constrained optimization method grounded in the global adjustment of nodal coordinates.First,a build direction is selected to minimize the number of violating struts.Then,an angular-constraint matrix is assembled from strut direction vectors,and analytical sensitivities with respect to nodal coordinates are derived to enable efficient constrained optimization under nonlinear angular inequality constraints.Numerical studies on two complex curved-surface lattices demonstrate that all overhang violations are eliminated while only minor changes are induced in global stiffness and strength.In particular,the maximum displacement of an ergonomic insole varies by only 2.87%after optimization.The results confirm the method’s versatility and engineering robustness,providing a practical approach for additive manufacturing-oriented lattice structure design.
文摘On the occasion of the 65th anniversary of the establishment of diplomatic relations between China and Laos,I wish to express,on behalf of the Embassy of the People's Republic of China in the Lao People's Democratic Republic,our sincere gratitude and highest respect to all friends and personages from various sectors in both countries who have long cared about and supported the development of our bilateral relations.
基金supported by the National Natural Science Foundation of China(No.12202295)the International(Regional)Cooperation and Exchange Projects of the National Natural Science Foundation of China(No.W2421002)+2 种基金the Sichuan Science and Technology Program(No.2025ZNSFSC0845)Zhejiang Provincial Natural Science Foundation of China(No.ZCLZ24A0201)the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.GK249909299001-004)。
文摘Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structural rigidity and flexibility,ensuring material integrity during large deformations,and providing adequate load-bearing capacity and stability once deployed.Most research has focused on optimizing cutout size and shape,while topology optimization offers a broader design space.However,the anisotropic properties of woven composite laminates,complex failure criteria,and multi-performance optimization needs have limited the exploration of topology optimization in this field.This work derives the sensitivities of bending stiffness,critical buckling load,and the failure index of woven composite materials with respect to element density,and formulates both single-objective and multi-objective topology optimization models using a linear weighted aggregation approach.The developed method was integrated with the commercial finite element software ABAQUS via a Python script,allowing efficient application to cutout design in various DCTWS configurations to maximize bending stiffness and critical buckling load under material failure constraints.Optimization of a classical tubular hinge resulted in improvements of 107.7%in bending stiffness and 420.5%in critical buckling load compared to level-set topology optimization results reported in the literature,validating the effectiveness of the approach.To facilitate future research and encourage the broader adoption of topology optimization techniques in DCTWS design,the source code for this work is made publicly available via a Git Hub link:https://github.com/jinhao-ok1/Topo-for-DCTWS.git.
