This study investigated the effects of planting duration(1,5,10 and 15 years)on soil properties,bacterial community diversity,and function in the rhizosphere of Zanthoxylum bungeanum.We employed Illumina highthroughpu...This study investigated the effects of planting duration(1,5,10 and 15 years)on soil properties,bacterial community diversity,and function in the rhizosphere of Zanthoxylum bungeanum.We employed Illumina highthroughput sequencing and PICRUSt2 functional prediction to analyze the structure and functional potential of rhizosphere soil bacterial communities.The Mantel test and redundancy analysis were used to identify physicochemical factors influencing bacterial community structure and function.The results indicated significant differences in rhizosphere soil physicochemical properties across planting years:the content of organic matter,alkaline hydrolyzable nitrogen in the soil,as well as the activity of invertase,urease,and alkaline phosphatase initially increased and then decreased,while available potassium,Olsen-phosphorus content,and peroxidase activity continued to increase.However,bacterial alpha diversity(Chao1 and Shannon indices)and the number of amplicon sequence variants increased continuously with planting duration.Principal coordinate analysis and Adonis tests revealed that the planting year significantly influenced the bacterial community structure(p<0.05).The phyla Proteobacteria,Actinobacteria,Acidobacteriota and Chloroflexi collectively constituted 56.7%to 71.2%of the relative abundance,representing the dominant taxa.PICRUSt2 predictions indicated key functional categories(cellular processes,metabolism,genetic information processing,and environmental information processing)each exceeding 10%relative abundance.BugBase analysis revealed a progressive increase in aerobic and oxidative stress-tolerant bacteria and a decrease in anaerobic and potentially pathogenic bacteria.Differential indicator species analysis identified Firmicutes,Planctomycetes,Methylomirabilota and Actinobacteriota as key discriminators for the 1-,5-,10-and 15-year stages,respectively.Organic matter,alkaline phosphatase,soil pH,and available phosphorus were the primary physicochemical drivers of bacterial communities.Notably,soil organic matter significantly influenced both the community structure(p<0.05)and predictedmetabolic functions(p<0.05).In conclusion,prolonged planting duration significantly enhanced rhizosphere microbial diversity and functional gene abundance in Z.bungeanumwhile driving the structural succession of bacterial communities dominated by Proteobacteria,Actinobacteria,Acidobacteriota,and Chloroflexi.This ecological shift,characterized by increased aerobic/oxidative-stress taxa and decreased anaerobic/pathogenic bacteria,was primarily regulated by soil organic matter,a key driver shaping both community structure and metabolic functions,ultimately improving soil microecological health.展开更多
The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is...The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is proposed,which generalizes the standard PFC algorithm to networked control systems with random delays.The algorithm uses the time-stamp method to estimate the control delay,predicts the future outputs based on a discrete time delay state space model,and drives the control law that applies to an NCS from the idea of a PFC algorithm.A networked control system was constructed based on TrueTime simulator,with which the time-stamped PFC algorithm was compared with the standard PFC algorithm.The response curves show that the proposed algorithm has better control performance.展开更多
The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squa...The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squarrosum(L.)Moq.is a pioneer plant used in sand fixation due to its strong resistance to drought and wind erosion.However,the bacterial community characteristics and ecological function in the rhizosphere of A.squarrosum are poorly understood.In this study,soil samples were collected from different developmental stages(seedling stage,vegetative stage,reproductive stage,and withering stage)of A.squarrosum.Illumina Miseq sequencing was used to detect differences in soil bacterial abundance.The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)program was used to predict bacterial functions,and the relationships among bacteria,functional populations,and soil nutrients were examined using a heatmap analysis.The results showed that the Shannon and Sobs indices of rhizosphere bacteria were significantly higher during the reproductive stage than during the other stages.Pantoea sp.(7.03%)was the dominant genus during the seedling stage;Arthrobacter sp.was the dominant genus during the vegetative(13.94%),reproductive(7.57%),and withering(12.30%)stages.The relative abundances of Chloroflexi,Acidobacteria,and Gemmatimonadetes were significantly high during the reproductive stage.According to the PICRUSt analysis,membrane transport,signal transduction,and environmental adaptation of the bacterial functional population occurred during the seedling stage.Carbohydrate metabolism increased during the vegetative stage,while energy metabolism,lipid metabolism,and biosynthesis of other secondary metabolites of the bacterial functional population significantly increased during the reproductive stage.The abundances of bacterial communities,functional genes,and soil nutrients were synergistically altered during various developmental stages.Our findings suggest that the developmental stages of A.squarrosum play a significant role in defining the composition and structure of bacterial communities in the rhizosphere.The results will provide a basis for better prediction and understanding of soil bacterial metabolic potential and functions of A.squarrosum rhizosphere in sandy areas.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
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
The Qinghai-Xizang Plateau presents an extreme environment characterized by high altitude,low oxygen availability,and harsh living conditions.High-altitude-residing amphibians,such as Rana kukunoris,have evolved speci...The Qinghai-Xizang Plateau presents an extreme environment characterized by high altitude,low oxygen availability,and harsh living conditions.High-altitude-residing amphibians,such as Rana kukunoris,have evolved specific physiological adaptations to survive in these habitats.However,the composition and functional significance of their gut microbiota with regard to these adaptations remain poorly explored.This study utilized 16S rR NA gene sequencing to characterize and compare the gut microbiota of Rana kukunoris with that of two low-altitude frogs,Rana amurensis and Rana dybowskii,to investigate potential microbial contributions to high-altitude adaptation.Results revealed significant differences in gut microbiota diversity and composition between high-and lowaltitude frogs.Notably,Akkermansia muciniphila and Desulfovibrio species were significantly enriched in Rana kukunoris.Functional predictions indicated significant enrichment of arginine biosynthesis pathways and associated metabolic processes in the high-altitude frog,which may enhance oxygen utilization and vascular homeostasis under hypoxic conditions.These findings provide insights into the gut microbiota of Rana kukunoris and suggest a potential crucial role in facilitating physiological adaptations to extreme environments through enhanced metabolic flexibility and stress resistance.展开更多
Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of...Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.展开更多
In order to obtain accurate prediction model and compensate for the influence of model mismatch on the control performance of the system and avoid solving nonlinear programming problem,an adaptive fuzzy predictive fun...In order to obtain accurate prediction model and compensate for the influence of model mismatch on the control performance of the system and avoid solving nonlinear programming problem,an adaptive fuzzy predictive functional control(AFPFC) scheme for multivariable nonlinear systems was proposed.Firstly,multivariable nonlinear systems were described based on Takagi-Sugeno(T-S) fuzzy models;assuming that the antecedent parameters of T-S models were kept,the consequent parameters were identified on-line by using the weighted recursive least square(WRLS) method.Secondly,the identified T-S models were linearized to be time-varying state space model at each sampling instant.Finally,by using linear predictive control technique the analysis solution of the optimal control law of AFPFC was established.The application results for pH neutralization process show that the absolute error between the identified T-S model output and the process output is smaller than 0.015;the tracking ability of the proposed AFPFC is superior to that of non-AFPFC(NAFPFC) for pH process without disturbances,the overshoot of the effluent pH value of AFPFC with disturbances is decreased by 50% compared with that of NAFPFC;when the process parameters of AFPFC vary with time the integrated absolute error(IAE) performance index still retains to be less than 200 compared with that of NAFPFC.展开更多
In heating, ventilating and air-conditioning （HVAC） systems, there exist severe nonlinearity, time-varying nature, disturbances and uncertainties. A new predictive functional control based on Takagi-Sugeno （T-S） f...In heating, ventilating and air-conditioning （HVAC） systems, there exist severe nonlinearity, time-varying nature, disturbances and uncertainties. A new predictive functional control based on Takagi-Sugeno （T-S） fuzzy model was proposed to control HVAC systems. The T-S fuzzy model of stabilized controlled process was obtained using the least squares method, then on the basis of global linear predictive model from T-S fuzzy model, the process was controlled by the predictive functional controller. Especially the feedback regulation part was developed to compensate uncertainties of fuzzy predictive model. Finally simulation test results in HVAC systems control applications showed that the proposed fuzzy model predictive functional control improves tracking effect and robustness. Compared with the conventional PID controller, this control strategy has the advantages of less overshoot and shorter setting time, etc.展开更多
The control of gas fractionation unit(GFU) in petroleum industry is very difficult due to multivariable characteristics and a large time delay.PID controllers are still applied in most industry processes.However,the t...The control of gas fractionation unit(GFU) in petroleum industry is very difficult due to multivariable characteristics and a large time delay.PID controllers are still applied in most industry processes.However,the traditional PID control has been proven not sufficient and capable for this particular petro-chemical process.In this work,an incremental multivariable predictive functional control(IMPFC) algorithm was proposed with less online computation,great precision and fast response.An incremental transfer function matrix model was set up through the step-response data,and predictive outputs were deduced with the theory of single-value optimization.The results show that the method can optimize the incremental control variable and reject the constraint of the incremental control variable with the positional predictive functional control algorithm,and thereby making the control variable smoother.The predictive output error and future set-point were approximated by a polynomial,which can overcome the problem under the model mismatch and make the predictive outputs track the reference trajectory.Then,the design of incremental multivariable predictive functional control was studied.Simulation and application results show that the proposed control strategy is effective and feasible to improve control performance and robustness of process.展开更多
The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of ...The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significandy reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process.展开更多
Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitab...Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.展开更多
By extending the system's state variables,a novel predictive functional controller has been developed.The structure of this controller is similar to that of classical proportional integral(PI)optimal controller an...By extending the system's state variables,a novel predictive functional controller has been developed.The structure of this controller is similar to that of classical proportional integral(PI)optimal controller and in-cludes a control block that can perform a feed-forward control of future P-step set points.It considers both the state variables and the output errors in its cost function,which results in enhanced control performance compared with traditional state space predictive functional control(TSSPFC)methods that consider only the predictive output er-rors.The predictive functional controller(PFC)has been compared with TSSPFC in terms of tracking ability,dis-turbance rejection,and also based on its application to heavy oil coking equipment.The results obtained show the effectiveness of the controller.展开更多
The main principle and the characteristic of Predictive Functional Control (PFC) strategy are presented in this paper and the corresponding control system aid design software APC-PFC is also introduced. For a chlorina...The main principle and the characteristic of Predictive Functional Control (PFC) strategy are presented in this paper and the corresponding control system aid design software APC-PFC is also introduced. For a chlorinated polyethylene (CPE) process, a design scheme of cascade predictive functional control system is described and the control performance is improved obviously.展开更多
Two systems of additive equations were developed to predict aboveground stand level biomass in log products and harvest residue from routinely measured or predicted stand variables for Pinus radiata plantations in New...Two systems of additive equations were developed to predict aboveground stand level biomass in log products and harvest residue from routinely measured or predicted stand variables for Pinus radiata plantations in New South Wales,Australia.These plantations were managed under three thinning regimes or stand types before clear-felling at rotation age by cut-to-length harvesters to produce sawlogs and pulpwood.The residue material following a clear-fell operation mainly consisted of stumps,branches and treetops,short off-cut and waste sections due to stem deformity,defects,damage and breakage.One system of equations did not include dummy variables for stand types in the model specification and was intended for more general use in plantations where stand density management regimes were not the same as the stand types in our study.The other system that incorporated dummy variables was for stand type-specific applications.Both systems of equations were estimated using 61 plot-based estimates of biomass in commercial logs and residue components that were derived from systems of equations developed in situ for predicting the product and residue biomass of individual trees.To cater for all practical applications,two sets of parameters were estimated for each system of equations for predicting component and total aboveground stand biomass in fresh and dry weight respectively.The two sets of parameters for the system of equations without dummy variables were jointly estimated to improve statistical efficiency in parameter estimation.The predictive performances of the two systems of equations were benchmarked through a leave-one-plot-out cross validation procedure.They were generally superior to the performance of an alternative two-stage approach that combined an additive system for major components with an allocative system for sub-components.As using forest harvest residue biomass for bioenergy has increasingly become an integrated part of forestry,reliable estimates of product and residue biomass will assist harvest and management planning for clear-fell operations that integrate cut-to-length log production with residue harvesting.展开更多
By establishing the concepts of fuzzy approaching set and fuzzy approaching functional mapping and making research on them, a new method for time series prediction is introduced.
Based on the octadecahedron of eleven-vertex closo-borane, the eleven-vertex closo-heteroborane was suggested with nonmetallic atoms instead of the different nonequivalent boron, and the stabilities were predicted at ...Based on the octadecahedron of eleven-vertex closo-borane, the eleven-vertex closo-heteroborane was suggested with nonmetallic atoms instead of the different nonequivalent boron, and the stabilities were predicted at G96PW91/6-31＋G（3d,2p） level. The small heteroatoms, C, N, O, preferentially occupy vertex 2 with the absolutely lowest relative energy to form the high stabilization closo-heteroboranes. They cap four-membered rings to satisfy the geometrical demand of short B--Z bonds. The electron attractions from the vicinal boron atoms make the frameworks shrink. Differently, Si and Ge preferentially substitute for boron at vertex 1 with six tight B--Z bonds and form stabilized molecules. P, As, S, and Se tend to occupy vertex 4 and the optimized structures belong to the nido configura- tions. In contrast to high electronegative heteroatoms, S and Se transfer less negative charges to framework and the electropositive heteroatoms, Si and Ge transfer more negative charges to framework to form the delocalization structures. The HOMO-LUMO gaps show that most of predicted clusters possess chemical stabilities. The substitutions of heteroatoms for boron atoms in eleven-vertex closo-heteroboranes are consistent with the topological charge stabilization rule proposed by Gimarc.展开更多
Among cases of spinal cord injury are injuries involving the dorsal column in the cervical spinal cord that interrupt the major cutaneous afferents from the hand to the cuneate nucleus（Cu）in the brainstem.Deprivatio...Among cases of spinal cord injury are injuries involving the dorsal column in the cervical spinal cord that interrupt the major cutaneous afferents from the hand to the cuneate nucleus（Cu）in the brainstem.Deprivation of touch and proprioceptive inputs consequently impair skilled hand use.展开更多
BACKGROUND Colorectal polyps that develop via the conventional adenoma-carcinoma sequence[e.g.,tubular adenoma(TA)]often progress to malignancy and are closely associated with changes in the composition of the gut mic...BACKGROUND Colorectal polyps that develop via the conventional adenoma-carcinoma sequence[e.g.,tubular adenoma(TA)]often progress to malignancy and are closely associated with changes in the composition of the gut microbiome.There is limited research concerning the microbial functions and gut microbiomes associated with colorectal polyps that arise through the serrated polyp pathway,such as hyperplastic polyps(HP).Exploration of microbiome alterations asso-ciated with HP and TA would improve the understanding of mechanisms by which specific microbes and their metabolic pathways contribute to colorectal carcinogenesis.AIM To investigate gut microbiome signatures,microbial associations,and microbial functions in HP and TA patients.METHODS Full-length 16S rRNA sequencing was used to characterize the gut microbiome in stool samples from control participants without polyps[control group(CT),n=40],patients with HP(n=52),and patients with TA(n=60).Significant differences in gut microbiome composition and functional mechanisms were identified between the CT group and patients with HP or TA.Analytical techniques in this study included differential abundance analysis,co-occurrence network analysis,and differential pathway analysis.RESULTS Colorectal cancer(CRC)-associated bacteria,including Streptococcus gallolyticus(S.gallolyticus),Bacteroides fragilis,and Clostridium symbiosum,were identified as characteristic microbial species in TA patients.Mediterraneibacter gnavus,associated with dysbiosis and gastrointestinal diseases,was significantly differentially abundant in the HP and TA groups.Functional pathway analysis revealed that HP patients exhibited enrichment in the sulfur oxidation pathway exclusively,whereas TA patients showed dominance in pathways related to secondary metabolite biosynthesis(e.g.,mevalonate);S.gallolyticus was a major contributor.Co-occurrence network and dynamic network analyses revealed co-occurrence of dysbiosis-associated bacteria in HP patients,whereas TA patients exhibited co-occurrence of CRC-associated bacteria.Furthermore,the co-occurrence of SCFA-producing bacteria was lower in TA patients than HP patients.CONCLUSION This study revealed distinct gut microbiome signatures associated with pathways of colorectal polyp development,providing insights concerning the roles of microbial species,functional pathways,and microbial interactions in colorectal carcinogenesis.展开更多
[Objective] The study was to analyze the structure and function of HpaGXoo and the relationship between the two.[Method] Some related bioinformatics analysis software on internet such as NPSA,Swiss-Model,SAPS and Inte...[Objective] The study was to analyze the structure and function of HpaGXoo and the relationship between the two.[Method] Some related bioinformatics analysis software on internet such as NPSA,Swiss-Model,SAPS and InterPro Scan were adopted to analyze the structure and predict its function.[Result] HpaGXoo consists of 139 amino acids,and has many alpha-helical and coiled structure,no signal peptide on N-terminal and no transmembrane structure.It locates in bacterial cytoplasm.[Conclusion] The study will lay ...展开更多
基金supported by Forestry and Grassland Science and Technology Innovation Project(LCKJCX2022001)from Forestry and Grassland Bureau of Gansu Province’s.
文摘This study investigated the effects of planting duration(1,5,10 and 15 years)on soil properties,bacterial community diversity,and function in the rhizosphere of Zanthoxylum bungeanum.We employed Illumina highthroughput sequencing and PICRUSt2 functional prediction to analyze the structure and functional potential of rhizosphere soil bacterial communities.The Mantel test and redundancy analysis were used to identify physicochemical factors influencing bacterial community structure and function.The results indicated significant differences in rhizosphere soil physicochemical properties across planting years:the content of organic matter,alkaline hydrolyzable nitrogen in the soil,as well as the activity of invertase,urease,and alkaline phosphatase initially increased and then decreased,while available potassium,Olsen-phosphorus content,and peroxidase activity continued to increase.However,bacterial alpha diversity(Chao1 and Shannon indices)and the number of amplicon sequence variants increased continuously with planting duration.Principal coordinate analysis and Adonis tests revealed that the planting year significantly influenced the bacterial community structure(p<0.05).The phyla Proteobacteria,Actinobacteria,Acidobacteriota and Chloroflexi collectively constituted 56.7%to 71.2%of the relative abundance,representing the dominant taxa.PICRUSt2 predictions indicated key functional categories(cellular processes,metabolism,genetic information processing,and environmental information processing)each exceeding 10%relative abundance.BugBase analysis revealed a progressive increase in aerobic and oxidative stress-tolerant bacteria and a decrease in anaerobic and potentially pathogenic bacteria.Differential indicator species analysis identified Firmicutes,Planctomycetes,Methylomirabilota and Actinobacteriota as key discriminators for the 1-,5-,10-and 15-year stages,respectively.Organic matter,alkaline phosphatase,soil pH,and available phosphorus were the primary physicochemical drivers of bacterial communities.Notably,soil organic matter significantly influenced both the community structure(p<0.05)and predictedmetabolic functions(p<0.05).In conclusion,prolonged planting duration significantly enhanced rhizosphere microbial diversity and functional gene abundance in Z.bungeanumwhile driving the structural succession of bacterial communities dominated by Proteobacteria,Actinobacteria,Acidobacteriota,and Chloroflexi.This ecological shift,characterized by increased aerobic/oxidative-stress taxa and decreased anaerobic/pathogenic bacteria,was primarily regulated by soil organic matter,a key driver shaping both community structure and metabolic functions,ultimately improving soil microecological health.
文摘The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is proposed,which generalizes the standard PFC algorithm to networked control systems with random delays.The algorithm uses the time-stamp method to estimate the control delay,predicts the future outputs based on a discrete time delay state space model,and drives the control law that applies to an NCS from the idea of a PFC algorithm.A networked control system was constructed based on TrueTime simulator,with which the time-stamped PFC algorithm was compared with the standard PFC algorithm.The response curves show that the proposed algorithm has better control performance.
基金supported by the Natural Science Foundation Project of Inner Mongolia Autonomous Region(2024LHMS03017)Research Capacity Enhancement“Unveiling and Leading”Project of Inner Mongolia Forestry Science Research Institute(2024NLTS03).
文摘The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squarrosum(L.)Moq.is a pioneer plant used in sand fixation due to its strong resistance to drought and wind erosion.However,the bacterial community characteristics and ecological function in the rhizosphere of A.squarrosum are poorly understood.In this study,soil samples were collected from different developmental stages(seedling stage,vegetative stage,reproductive stage,and withering stage)of A.squarrosum.Illumina Miseq sequencing was used to detect differences in soil bacterial abundance.The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)program was used to predict bacterial functions,and the relationships among bacteria,functional populations,and soil nutrients were examined using a heatmap analysis.The results showed that the Shannon and Sobs indices of rhizosphere bacteria were significantly higher during the reproductive stage than during the other stages.Pantoea sp.(7.03%)was the dominant genus during the seedling stage;Arthrobacter sp.was the dominant genus during the vegetative(13.94%),reproductive(7.57%),and withering(12.30%)stages.The relative abundances of Chloroflexi,Acidobacteria,and Gemmatimonadetes were significantly high during the reproductive stage.According to the PICRUSt analysis,membrane transport,signal transduction,and environmental adaptation of the bacterial functional population occurred during the seedling stage.Carbohydrate metabolism increased during the vegetative stage,while energy metabolism,lipid metabolism,and biosynthesis of other secondary metabolites of the bacterial functional population significantly increased during the reproductive stage.The abundances of bacterial communities,functional genes,and soil nutrients were synergistically altered during various developmental stages.Our findings suggest that the developmental stages of A.squarrosum play a significant role in defining the composition and structure of bacterial communities in the rhizosphere.The results will provide a basis for better prediction and understanding of soil bacterial metabolic potential and functions of A.squarrosum rhizosphere in sandy areas.
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 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 Open Project Funding of the Key Laboratory of Southwest China Wildlife Resource Conservation (Ministry of Education) (XNYB24-02)。
文摘The Qinghai-Xizang Plateau presents an extreme environment characterized by high altitude,low oxygen availability,and harsh living conditions.High-altitude-residing amphibians,such as Rana kukunoris,have evolved specific physiological adaptations to survive in these habitats.However,the composition and functional significance of their gut microbiota with regard to these adaptations remain poorly explored.This study utilized 16S rR NA gene sequencing to characterize and compare the gut microbiota of Rana kukunoris with that of two low-altitude frogs,Rana amurensis and Rana dybowskii,to investigate potential microbial contributions to high-altitude adaptation.Results revealed significant differences in gut microbiota diversity and composition between high-and lowaltitude frogs.Notably,Akkermansia muciniphila and Desulfovibrio species were significantly enriched in Rana kukunoris.Functional predictions indicated significant enrichment of arginine biosynthesis pathways and associated metabolic processes in the high-altitude frog,which may enhance oxygen utilization and vascular homeostasis under hypoxic conditions.These findings provide insights into the gut microbiota of Rana kukunoris and suggest a potential crucial role in facilitating physiological adaptations to extreme environments through enhanced metabolic flexibility and stress resistance.
基金funded by National Natural Science Foundation of China(project no.31872417)。
文摘Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.
基金Project(2007AA04Z162) supported by the National High-Tech Research and Development Program of ChinaProjects(2006T089, 2009T062) supported by the University Innovation Team in the Educational Department of Liaoning Province, China
文摘In order to obtain accurate prediction model and compensate for the influence of model mismatch on the control performance of the system and avoid solving nonlinear programming problem,an adaptive fuzzy predictive functional control(AFPFC) scheme for multivariable nonlinear systems was proposed.Firstly,multivariable nonlinear systems were described based on Takagi-Sugeno(T-S) fuzzy models;assuming that the antecedent parameters of T-S models were kept,the consequent parameters were identified on-line by using the weighted recursive least square(WRLS) method.Secondly,the identified T-S models were linearized to be time-varying state space model at each sampling instant.Finally,by using linear predictive control technique the analysis solution of the optimal control law of AFPFC was established.The application results for pH neutralization process show that the absolute error between the identified T-S model output and the process output is smaller than 0.015;the tracking ability of the proposed AFPFC is superior to that of non-AFPFC(NAFPFC) for pH process without disturbances,the overshoot of the effluent pH value of AFPFC with disturbances is decreased by 50% compared with that of NAFPFC;when the process parameters of AFPFC vary with time the integrated absolute error(IAE) performance index still retains to be less than 200 compared with that of NAFPFC.
基金This work was supported by Young Scientists Fundamental Research Program of Shandong Province of China (No. 031B5147).
文摘In heating, ventilating and air-conditioning （HVAC） systems, there exist severe nonlinearity, time-varying nature, disturbances and uncertainties. A new predictive functional control based on Takagi-Sugeno （T-S） fuzzy model was proposed to control HVAC systems. The T-S fuzzy model of stabilized controlled process was obtained using the least squares method, then on the basis of global linear predictive model from T-S fuzzy model, the process was controlled by the predictive functional controller. Especially the feedback regulation part was developed to compensate uncertainties of fuzzy predictive model. Finally simulation test results in HVAC systems control applications showed that the proposed fuzzy model predictive functional control improves tracking effect and robustness. Compared with the conventional PID controller, this control strategy has the advantages of less overshoot and shorter setting time, etc.
基金Project(61203021)supported by the National Natural Science Foundation of ChinaProject(2011216011)supported by the Scientific and Technological Program of Liaoning Province,China+2 种基金Project(2013020024)supported by the Natural Science Foundation of Liaoning Province,ChinaProject(2012BAF05B00)supported by the National Science and Technology Support Program,ChinaProject(LJQ2015061)supported by the Program for Liaoning Excellent Talents in Universities,China
文摘The control of gas fractionation unit(GFU) in petroleum industry is very difficult due to multivariable characteristics and a large time delay.PID controllers are still applied in most industry processes.However,the traditional PID control has been proven not sufficient and capable for this particular petro-chemical process.In this work,an incremental multivariable predictive functional control(IMPFC) algorithm was proposed with less online computation,great precision and fast response.An incremental transfer function matrix model was set up through the step-response data,and predictive outputs were deduced with the theory of single-value optimization.The results show that the method can optimize the incremental control variable and reject the constraint of the incremental control variable with the positional predictive functional control algorithm,and thereby making the control variable smoother.The predictive output error and future set-point were approximated by a polynomial,which can overcome the problem under the model mismatch and make the predictive outputs track the reference trajectory.Then,the design of incremental multivariable predictive functional control was studied.Simulation and application results show that the proposed control strategy is effective and feasible to improve control performance and robustness of process.
基金This work was supported by National Science Fundation of China (No.60274032)Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) (No.20030248040)and Alexander von Humboldt Research Fellowship
文摘The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significandy reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process.
文摘Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.
基金Supported by the National Creative Research Groups Science Foundation of China (NCRGSFC 60421002)the National High Technology Research and Development Program of China (863 Program,2006AA04Z182).
文摘By extending the system's state variables,a novel predictive functional controller has been developed.The structure of this controller is similar to that of classical proportional integral(PI)optimal controller and in-cludes a control block that can perform a feed-forward control of future P-step set points.It considers both the state variables and the output errors in its cost function,which results in enhanced control performance compared with traditional state space predictive functional control(TSSPFC)methods that consider only the predictive output er-rors.The predictive functional controller(PFC)has been compared with TSSPFC in terms of tracking ability,dis-turbance rejection,and also based on its application to heavy oil coking equipment.The results obtained show the effectiveness of the controller.
文摘The main principle and the characteristic of Predictive Functional Control (PFC) strategy are presented in this paper and the corresponding control system aid design software APC-PFC is also introduced. For a chlorinated polyethylene (CPE) process, a design scheme of cascade predictive functional control system is described and the control performance is improved obviously.
基金This study was supported by the Australian Government Department of Agriculture,Fisheries and Forestry,the Rural Industries Research and Development Corporation,and Forests NSW.
文摘Two systems of additive equations were developed to predict aboveground stand level biomass in log products and harvest residue from routinely measured or predicted stand variables for Pinus radiata plantations in New South Wales,Australia.These plantations were managed under three thinning regimes or stand types before clear-felling at rotation age by cut-to-length harvesters to produce sawlogs and pulpwood.The residue material following a clear-fell operation mainly consisted of stumps,branches and treetops,short off-cut and waste sections due to stem deformity,defects,damage and breakage.One system of equations did not include dummy variables for stand types in the model specification and was intended for more general use in plantations where stand density management regimes were not the same as the stand types in our study.The other system that incorporated dummy variables was for stand type-specific applications.Both systems of equations were estimated using 61 plot-based estimates of biomass in commercial logs and residue components that were derived from systems of equations developed in situ for predicting the product and residue biomass of individual trees.To cater for all practical applications,two sets of parameters were estimated for each system of equations for predicting component and total aboveground stand biomass in fresh and dry weight respectively.The two sets of parameters for the system of equations without dummy variables were jointly estimated to improve statistical efficiency in parameter estimation.The predictive performances of the two systems of equations were benchmarked through a leave-one-plot-out cross validation procedure.They were generally superior to the performance of an alternative two-stage approach that combined an additive system for major components with an allocative system for sub-components.As using forest harvest residue biomass for bioenergy has increasingly become an integrated part of forestry,reliable estimates of product and residue biomass will assist harvest and management planning for clear-fell operations that integrate cut-to-length log production with residue harvesting.
文摘By establishing the concepts of fuzzy approaching set and fuzzy approaching functional mapping and making research on them, a new method for time series prediction is introduced.
文摘Based on the octadecahedron of eleven-vertex closo-borane, the eleven-vertex closo-heteroborane was suggested with nonmetallic atoms instead of the different nonequivalent boron, and the stabilities were predicted at G96PW91/6-31＋G（3d,2p） level. The small heteroatoms, C, N, O, preferentially occupy vertex 2 with the absolutely lowest relative energy to form the high stabilization closo-heteroboranes. They cap four-membered rings to satisfy the geometrical demand of short B--Z bonds. The electron attractions from the vicinal boron atoms make the frameworks shrink. Differently, Si and Ge preferentially substitute for boron at vertex 1 with six tight B--Z bonds and form stabilized molecules. P, As, S, and Se tend to occupy vertex 4 and the optimized structures belong to the nido configura- tions. In contrast to high electronegative heteroatoms, S and Se transfer less negative charges to framework and the electropositive heteroatoms, Si and Ge transfer more negative charges to framework to form the delocalization structures. The HOMO-LUMO gaps show that most of predicted clusters possess chemical stabilities. The substitutions of heteroatoms for boron atoms in eleven-vertex closo-heteroboranes are consistent with the topological charge stabilization rule proposed by Gimarc.
基金supported by NIH grants NS067017 to HXQNS16446 to JHK
文摘Among cases of spinal cord injury are injuries involving the dorsal column in the cervical spinal cord that interrupt the major cutaneous afferents from the hand to the cuneate nucleus（Cu）in the brainstem.Deprivation of touch and proprioceptive inputs consequently impair skilled hand use.
基金Supported by Chulabhorn Royal Academy(Fundamental Fund:Fiscal year 2022 by National Science Research and Innovation Fund),No.FRB650039/0240 Project Code 165422.
文摘BACKGROUND Colorectal polyps that develop via the conventional adenoma-carcinoma sequence[e.g.,tubular adenoma(TA)]often progress to malignancy and are closely associated with changes in the composition of the gut microbiome.There is limited research concerning the microbial functions and gut microbiomes associated with colorectal polyps that arise through the serrated polyp pathway,such as hyperplastic polyps(HP).Exploration of microbiome alterations asso-ciated with HP and TA would improve the understanding of mechanisms by which specific microbes and their metabolic pathways contribute to colorectal carcinogenesis.AIM To investigate gut microbiome signatures,microbial associations,and microbial functions in HP and TA patients.METHODS Full-length 16S rRNA sequencing was used to characterize the gut microbiome in stool samples from control participants without polyps[control group(CT),n=40],patients with HP(n=52),and patients with TA(n=60).Significant differences in gut microbiome composition and functional mechanisms were identified between the CT group and patients with HP or TA.Analytical techniques in this study included differential abundance analysis,co-occurrence network analysis,and differential pathway analysis.RESULTS Colorectal cancer(CRC)-associated bacteria,including Streptococcus gallolyticus(S.gallolyticus),Bacteroides fragilis,and Clostridium symbiosum,were identified as characteristic microbial species in TA patients.Mediterraneibacter gnavus,associated with dysbiosis and gastrointestinal diseases,was significantly differentially abundant in the HP and TA groups.Functional pathway analysis revealed that HP patients exhibited enrichment in the sulfur oxidation pathway exclusively,whereas TA patients showed dominance in pathways related to secondary metabolite biosynthesis(e.g.,mevalonate);S.gallolyticus was a major contributor.Co-occurrence network and dynamic network analyses revealed co-occurrence of dysbiosis-associated bacteria in HP patients,whereas TA patients exhibited co-occurrence of CRC-associated bacteria.Furthermore,the co-occurrence of SCFA-producing bacteria was lower in TA patients than HP patients.CONCLUSION This study revealed distinct gut microbiome signatures associated with pathways of colorectal polyp development,providing insights concerning the roles of microbial species,functional pathways,and microbial interactions in colorectal carcinogenesis.
基金Supported by Langfang Teachers College Research Grant(LSZB200803)~~
文摘[Objective] The study was to analyze the structure and function of HpaGXoo and the relationship between the two.[Method] Some related bioinformatics analysis software on internet such as NPSA,Swiss-Model,SAPS and InterPro Scan were adopted to analyze the structure and predict its function.[Result] HpaGXoo consists of 139 amino acids,and has many alpha-helical and coiled structure,no signal peptide on N-terminal and no transmembrane structure.It locates in bacterial cytoplasm.[Conclusion] The study will lay ...
