This study investigates the performance of high-strength cable bolts under impact loading conditions representative of rock bursts in underground environments.Although widely used,the dynamic behaviour of these cable ...This study investigates the performance of high-strength cable bolts under impact loading conditions representative of rock bursts in underground environments.Although widely used,the dynamic behaviour of these cable bolts has received limited experimental attention,and their effectiveness in seismically active zones remains a subject of ongoing debate.To address this gap,a reverse pull-out test machine integrated with a drop hammer rig was employed.Tests were conducted on 70-t SUMO bulbed and non-bulbed cable bolts with encapsulation lengths of 300 and 450 mm,subjected to an impact energy of 14.52 k J.Results indicate that non-bulbed cables,despite showing lower initial peak loads(average 218 vs.328 k N for bulbed cables at 300 mm encapsulation),demonstrated superior energy absorption(average 11.26 vs.8.75 k J)and displacement capacity(average 48.40 vs.36.25 mm).Increasing the encapsulation length for bulbed cables led to a reduction in initial peak load but improved displacement and energy absorption.The dominant failure mechanism was debonding at the cable-grout interface,characterised by frictional sliding and cable rotation.These findings provide new insights into the energy dissipation mechanisms of cables and support the development of more resilient ground support systems for dynamically active conditions.展开更多
Water inrush hazards from the floor strata of longwall workingface are commonly encountered in North China coalfields,which essentially result from the evolution of permeability in the floor rock under complex mining-...Water inrush hazards from the floor strata of longwall workingface are commonly encountered in North China coalfields,which essentially result from the evolution of permeability in the floor rock under complex mining-induced stress conditions.Current research rarely addresses the evolution of rock permeability under such complex stress paths.Describing this evolution using only one stress parameter,such as effective stress,deviatoric stress,axial stress,or confining stress,is highly challenging.In this study,we developed a laboratory loading scheme that simulates mining-induced stress evolution.Hydro-mechanical experiments were conducted to investigate the evolution of rock permeability under mining stress.The mechanism on the change of stress-permeability relationships in mining-disturbed rock is revealed,supporting to the analysis of management strategies for floor water-inrush disasters.The results show that rock permeability evolves through four stages,including rapid decline,gradual fluctuation,sharp increase,and slow attenuation.1–2 permeability surges occurred during mining-stress loading,closely linked to the emergence and reversal of deviatoric stress in magnitude and direction.With the first permeability surge,the deviatoric stress within the mudstone reached approximately 1.7 MPa,whereas that of the sandstone was about 1 MPa.The second permeability surge in the mudstone corresponded to the secondary rotation of the principal stress direction.CT and ultrasonic tests suggested an increase in microcracks in both rocks during the first permeability surge.However,the deviatoric stress-permeability plot before and after mining indicated that the fracture of mudstone sample changed significantly,while that of the sandstone remained unchanged.The permeability surges observed at different stages are interpreted as resulting from shear-induced reopening of pre-existing fractures and the formation of new shear-failure fractures.A stress-permeability model jointly governed by effective mean stress and deviatoric stress was established.Furthermore,two strategies are proposed for the floor water-inrush disasters prevention,(i)timely backfilling to reduce deviatoric stress,(ii)grouting after the first permeability surge.This work provides insights into stress-seepage behavior in rocks under complex stress evolution and offers new perspectives for identifying potential water inrush pathways in the floor strata of coal seam during longwall mining.展开更多
Enzyme-Induced Carbonate Precipitation(EICP)is an innovative technique to improve soil strength and reduce permeability.However,the use of EICP for reinforcing underwater sand beds remains largely unexplored.To advanc...Enzyme-Induced Carbonate Precipitation(EICP)is an innovative technique to improve soil strength and reduce permeability.However,the use of EICP for reinforcing underwater sand beds remains largely unexplored.To advance EICP implementation in various geotechnical applications,this paper develops a model box system to investigate the effectiveness of the EICP technique in reinforcing underwater sand beds.An"injection-extraction"system is designed to facilitate the flow of the EICP solution through underwater sand layers.Key parameters,including conductivity,pH,and Ca^(2+)concentration of the solution,are measured and analyzed.Electrical resistivity tomography(ERT)is utilized to evaluate the reinforcement effect in the underwater sand bed.The permeability of the model is tested to verify the feasibility of EICP technology for strengthening underwater sands.Furthermore,scanning electron microscope(SEM)is performed to investigate the growth mechanisms of calcium carbonate(CaCO_(3))crystals.The results show that the permeability of the model decreases from 1.28×10^(-2)m/s to 9.66×10^(-5)m/s,representing a reduction of approximately three orders of magnitude.This verifies that the EICP technology can greatly reduce the permeability of underwater sand beds.With increasing grouting cycles,the resistivity of the underwater sand initially decreases and then increases.This variation in sand resistivity is significantly influenced by the ion concentration in the solution,resulting in marked differences in resistivity at various depths and positions within the sand.The findings from this study offer a theoretical basis for the application of EICP technology in reinforcing seabed foundations and supporting marine infrastructure such as offshore pipelines,wind turbines,and oil platforms.展开更多
Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper ...Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper equations are one of the main and most efficient methods for estimating stem volume to any merchantable limit of a species.There is currently no taper equation for Eucalyptus species in Nigeria.Therefore,this study developed taper equations for E.camaldulensis in northern Nigeria.Data for this study were obtained from a private plantation in Jalingo Local Government Area,Taraba State,Nigeria.68 trees were felled and sectioned into 1-m bolt across the stem to a merchantable limit of 5 cm,which were used as the fitting dataset.An additional 22 trees were felled and used to validate the taper equations for stem volume estimation.Seven taper equations were initially fitted to the dataset using nonlinear least squares.The best taper equation was then refitted using a nonlinear mixed-effects approach and calibrated using diameters of one to five sections from the butt end.The taper equations were numerically integrated to obtain the stem volume,which was compared with empirical volume equations.The result shows that the Kozak(Can J For Res 27(5):619-629.10.1139/x97-011,1997)equation,which included eight parameters,provided the best fit for predicting section diameters for under and over bark.The mixed-effects taper equation(NLME-TE)explained most stem diameter variations in the fitting dataset(pseudo-R2:0.986-0.987;RMSE:0.547-0.578 cm)without substantial residual trends.The validation showed that the prediction accuracy of the integrated NLME-TE improved as the number of sectional diameter measurements increased,with at least a 35%reduction in volume estimate error.For practical implementation,two calibration sectional diameter measurements taken from the butt end per tree are recommended.This approach would reduce measurement effort and cost while improving model performance.展开更多
Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temp...Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.展开更多
Soft-tissue motion introduces significant challenges in robotic teleoperation,especially in medical scenarios where precise target tracking is critical.Latency across sensing,computation,and actuation chains leads to ...Soft-tissue motion introduces significant challenges in robotic teleoperation,especially in medical scenarios where precise target tracking is critical.Latency across sensing,computation,and actuation chains leads to degraded tracking performance,particularly around high-acceleration segments and trajectory inflection points.This study investigates machine learning-based predictive compensation for latency mitigation in soft-tissue tracking.Three models—autoregressive(AR),long short-term memory(LSTM),and temporal convolutional network(TCN)—were implemented and evaluated on both synthetic and real datasets.By aligning the prediction horizon with the end-to-end system delay,we demonstrate that prediction-based compensation significantly reduces tracking errors.Among the models,TCN achieved superior robustness and accuracy on complex motion patterns,particularly in multi-step prediction tasks,and exhibited better latency–horizon compatibility.The results suggest that TCN is a promising candidate for real-time latency compensation in teleoperated robotic systems involving dynamic soft-tissue interaction.展开更多
The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses ...The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses substantial challenges.Issues such as water scarcity,energy crises,escalating greenhouse gas emissions,and diminishing farm profitability threaten longterm agricultural sustainability.In response,we applied a holistic food–carbon–nitrogen–water–energy–profit (FCNWEP)nexus framework to comprehensively assess the sustainability of distinct crop management strategies across three subsites in Central China.Field experiments were conducted in Hubei and Hunan provinces from 2017 to 2021 using a widely adopted elite super hybrid rice cultivar (Y-liangyou 900).Four crop management treatments were implemented:a control(CK,0 kg N ha^(-1)),conventional crop management (CCM,210–250 kg N ha^(-1),7:3 basal:mid-tiller fertilizer ratio),and two integrated crop management (ICM) treatments (ICM1,180–210 kg N ha^(-1),5:2:3 basal:mid-tiller:panicle initiation fertilizer ratio;ICM2,240–270 kg N ha^(-1),5:2:2:1 basal:mid-tiller:panicle initiation:flowering fertilizer ratio).Variables assessed included grain yield,carbon footprint,nitrogen footprint,water footprint,energy footprint,nitrogen use efficiency,and economic benefits.Our results showed significant yield variations,with ICM2 consistently outperforming CCM and ICM1across all three sites.In Jingzhou,Suizhou,and Changsha,ICM2’s grain yield was 30.2,24.7,and 13.3%higher than CCM,respectively.Net profits under ICM2 exceeded those of CCM and ICM1 by 31.8 and 115.2%in Jingzhou,32.2 and 109.9%in Suizhou,and 15.4 and 34.0%in Changsha,respectively.Integrated crop management,particularly ICM2,demonstrated improved nitrogen and energy use efficiency,leading to reduced carbon,nitrogen,water,and energy footprints.Overall,composite sustainability scores derived from the FCNWEP framework indicated that both ICM2 and ICM1 exhibited higher sustainability levels compared to CCM.This study provides valuable insights into practical management methodologies and offers recommendations for enhancing agricultural sustainability.展开更多
Although machine learning models have achieved high enough accuracy in predicting shield position deviations,their“black box”nature makes the prediction mechanisms and decision-making processes opaque,leading to wea...Although machine learning models have achieved high enough accuracy in predicting shield position deviations,their“black box”nature makes the prediction mechanisms and decision-making processes opaque,leading to weaker explanations and practicability.This study introduces a novel explainable deep learning framework comprising the Informer model with enhanced attention mechanisms(EAMInfor)and deep learning important features(DeepLIFT),aimed at improving the prediction accuracy of shield position deviations and providing interpretability for predictive results.The EAMInfor model attempts to integrate channel attention,spatial attention,and simple attention modules to improve the Informer model's performance.The framework is tested with the four different geological conditions datasets generated from the Xiamen metro line 3,China.Results show that the EAMInfor model outperforms the traditional Informer and comparison models.The analysis with the DeepLIFT method indicates that the push thrust of push cylinder and the earth chamber pressure are the most significant features,while the stroke length of the push cylinder demonstrated lower importance.Furthermore,the variation trends in the significance of data points within input sequences exhibit substantial differences between single and composite strata.This framework not only improves predictive accuracy but also strengthens the credibility and reliability of the results.展开更多
Graph Neural Networks(GNNs),as a deep learning framework specifically designed for graph-structured data,have achieved deep representation learning of graph data through message passing mechanisms and have become a co...Graph Neural Networks(GNNs),as a deep learning framework specifically designed for graph-structured data,have achieved deep representation learning of graph data through message passing mechanisms and have become a core technology in the field of graph analysis.However,current reviews on GNN models are mainly focused on smaller domains,and there is a lack of systematic reviews on the classification and applications of GNN models.This review systematically synthesizes the three canonical branches of GNN,Graph Convolutional Network(GCN),Graph Attention Network(GAT),and Graph Sampling Aggregation Network(GraphSAGE),and analyzes their integration pathways from both structural and feature perspectives.Drawing on representative studies,we identify three major integration patterns:cascaded fusion,where heterogeneous modules such as Convolutional Neural Network(CNN),Long Short-Term Memory(LSTM),and GraphSAGE are sequentially combined for hierarchical feature learning;parallel fusion,where multi-branch architectures jointly encode complementary graph features;and feature-level fusion,which employs concatenation,weighted summation,or attention-based gating to adaptively merge multi-source embeddings.Through these patterns,integrated GNNs achieve enhanced expressiveness,robustness,and scalability across domains including transportation,biomedicine,and cybersecurity.展开更多
The application of conventional manganese dioxide(MnO_(2))materials in sodium-ion supercapacitors(Na-SCs)is considerably limited by their low conductivity and structural instability.Biomimetic morphology engineering c...The application of conventional manganese dioxide(MnO_(2))materials in sodium-ion supercapacitors(Na-SCs)is considerably limited by their low conductivity and structural instability.Biomimetic morphology engineering can optimize the electrochemical performance of MnO_(2).Here,based on the metal-organic frameworks(MOFs)-derived method and electrochemical reconstruction,a coral-like MnO_(2)structure integrated with a functional nitrogen-doped carbon(NC)coating is designed for Na-SC application.The bioinspired coral-like structure captures numerous electrolyte ions and increases the Na+concentration on the electrode surface,which is beneficial for optimizing the Na+transport pathway and accelerating the electrode reaction kinetics.Moreover,the coral-like crosslinked structure effectively enhances the mechanical properties,enabling the maintenance of the structure of MnO_(2)-based electrodes during long-term operation.Furthermore,in/ex-situ characterizations are performed to elucidate the mechanism of lattice transformation during electrochemical phase reconstruction.Additionally,the theoretical calculation and simulation results reveal the ion/electron dynamics in the fabricated electrode.The prepared electrode demonstrates excellent capacitance storage ability(340.7 F g^(−1)at 0.5 A g^(−1))and cycling stability(85.1%capacitance retention after 10,000 cycles).The assembled hybrid device exhibits exceptional life-span(82.0%capacitance retention after 10,000 cycles)and exceptional energy density(36.5 Wh kg^(−1)).This study provides a reliable biomimetic morphology design strategy for MnO_(2)cathodes,paving the way for the fabrication of high-performance Na-SCs.展开更多
The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the...The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the OA meniscus is very important.This study aimed to assess the quasi-static nonlinear mechanical behaviours of the three zones of the OA meniscus by a proposed meso-indentation method,and further to investigate its nonlinear mechanical responses under the stance.Four pairs of menisci were harvested from OA patients during total knee arthroplasty.One pair of the menisci was first used for the histological analysis.Binocular fringe projection technology was then employed to reconstruct the morphology of the other three pairs of the menisci.Subsequently,a meso-indentation method was proposed to characterize the nonlinear behaviors of the meniscus zones,moreover,the hyperelastic model(HEM)together with the Hertz’s elastic model(EM)was used to fit the indentation force-depth curves of the meniscus zones.Furthermore,the fitted HEM and EM materials parameters were used to simulate the mechanical response of the meniscus in the stance by two simplified meniscus models.The results showed that the type III collagen widely existed in the OA menisci,and the red-white zone exhibited the best mechanical performance,and the 3-term Mooney-Rivlin model was the best descriptor for the nonlinear mechanical characterization of the three zones.Moreover,the stress or strain distributions of the simplified meniscus models differed significantly between the HEM and EM under the stance,and the EM underestimated the mechanical behaviours of the meniscus.The current work generally provides a novel testing method to study the nonlinear mechanical behaviour of soft biological materials,and is specifically helpful to understand the nonlinear mechanical behaviour of the OA meniscus for which the HEM should be used in the meniscus-related biomechanical studies.展开更多
Purpose We aimed to investigate the effects of running shoe longitudinal bending stiffness(LBS)and midsole energy return on running economy and ankle mechanics and energetics.Methods PubMed,Scopus,SPORTDiscus,Embase,C...Purpose We aimed to investigate the effects of running shoe longitudinal bending stiffness(LBS)and midsole energy return on running economy and ankle mechanics and energetics.Methods PubMed,Scopus,SPORTDiscus,Embase,CINAHL,and Web of Science were systematically searched for this meta-analysis.Crossover studies comparing the effects of running shoe LBS and/or midsole energy return on at least 1 of the following outcomes:running economy,ankle plantarflexion moment,work,power,or angular velocity were included.Results Of the 2453 studies screened,48 were included(n=878).Results indicated that advanced footwear technologies(AFTs)significantly reduced oxygen consumption(standardized mean difference=–0.44,95%confidence interval:–0.60 to–0.28),p<0.001)as well as peak ankle moments and positive/negative ankle work and power.However,neither LBS nor midsole energy return alone significantly affected oxygen consumption,ankle moments,positive and negative work,or positive power.The effects of AFTs were moderated by the training status and speed of the runner.The quality of evidence for all outcomes were low or very low for all outcomes except the effect of LBS on negative ankle work.Conclusion AFT may improve running economy by minimizing ankle moments,work,and power.The absence of significant independent effects of LBS and midsole energy return suggests that the benefits of AFTs arise from the interaction of these properties.Further research is necessary to understand the mechanisms for improved running performance in AFTs.展开更多
Parkinson's disease(PD) has a complex and multifactorial pathophysiology. Various studies, conducted both in pre-clinical models and PD patients, have reported a link between the disruption of calcium(Ca^(2+)) hom...Parkinson's disease(PD) has a complex and multifactorial pathophysiology. Various studies, conducted both in pre-clinical models and PD patients, have reported a link between the disruption of calcium(Ca^(2+)) homeostasis and the subsequent development of PD. Ca^(2+) regulation is crucial for neuronal survival, differentiation,exocytosis at synapses,gene transcription,and proliferation.展开更多
This review focuses on the diagnostic algorithm for nonobstructive azoospermia(NOA),a significant male factor contributing to infertility.NOA,characterized by the absence of sperm in the ejaculate,requires a systemati...This review focuses on the diagnostic algorithm for nonobstructive azoospermia(NOA),a significant male factor contributing to infertility.NOA,characterized by the absence of sperm in the ejaculate,requires a systematic diagnostic approach to identify reversible conditions,genetic factors,and prognosis for achieving pregnancy.The diagnostic pathway involves semen analysis and a comprehensive evaluation for hormonal deficiencies,anatomical abnormalities,and genetic factors.The importance of medical history,physical examination,endocrine evaluation,imaging,and genetic testing is emphasized.This review highlights the significance of differentiating NOA from obstructive azoospermia(OA)and outlines key considerations for effective management,including surgical sperm retrieval and assisted reproductive techniques.Testicular biopsy is discussed as a definitive method to distinguish obstructive cases from nonobstructive cases,providing valuable prognostic information.Overall,a thorough and systematic diagnostic approach is essential for the effective management of men suspected with NOA,offering insights into potential treatment options and reproductive outcomes.展开更多
文摘This study investigates the performance of high-strength cable bolts under impact loading conditions representative of rock bursts in underground environments.Although widely used,the dynamic behaviour of these cable bolts has received limited experimental attention,and their effectiveness in seismically active zones remains a subject of ongoing debate.To address this gap,a reverse pull-out test machine integrated with a drop hammer rig was employed.Tests were conducted on 70-t SUMO bulbed and non-bulbed cable bolts with encapsulation lengths of 300 and 450 mm,subjected to an impact energy of 14.52 k J.Results indicate that non-bulbed cables,despite showing lower initial peak loads(average 218 vs.328 k N for bulbed cables at 300 mm encapsulation),demonstrated superior energy absorption(average 11.26 vs.8.75 k J)and displacement capacity(average 48.40 vs.36.25 mm).Increasing the encapsulation length for bulbed cables led to a reduction in initial peak load but improved displacement and energy absorption.The dominant failure mechanism was debonding at the cable-grout interface,characterised by frictional sliding and cable rotation.These findings provide new insights into the energy dissipation mechanisms of cables and support the development of more resilient ground support systems for dynamically active conditions.
基金supported by the National Natural Science Foundation of China(Nos.U22A20165 and 52474156)the Key Research and Development Program of Xinjiang Uyghur Autonomous Region(No.2023B01010-1)the China Scholarship Council(No.202406420054).
文摘Water inrush hazards from the floor strata of longwall workingface are commonly encountered in North China coalfields,which essentially result from the evolution of permeability in the floor rock under complex mining-induced stress conditions.Current research rarely addresses the evolution of rock permeability under such complex stress paths.Describing this evolution using only one stress parameter,such as effective stress,deviatoric stress,axial stress,or confining stress,is highly challenging.In this study,we developed a laboratory loading scheme that simulates mining-induced stress evolution.Hydro-mechanical experiments were conducted to investigate the evolution of rock permeability under mining stress.The mechanism on the change of stress-permeability relationships in mining-disturbed rock is revealed,supporting to the analysis of management strategies for floor water-inrush disasters.The results show that rock permeability evolves through four stages,including rapid decline,gradual fluctuation,sharp increase,and slow attenuation.1–2 permeability surges occurred during mining-stress loading,closely linked to the emergence and reversal of deviatoric stress in magnitude and direction.With the first permeability surge,the deviatoric stress within the mudstone reached approximately 1.7 MPa,whereas that of the sandstone was about 1 MPa.The second permeability surge in the mudstone corresponded to the secondary rotation of the principal stress direction.CT and ultrasonic tests suggested an increase in microcracks in both rocks during the first permeability surge.However,the deviatoric stress-permeability plot before and after mining indicated that the fracture of mudstone sample changed significantly,while that of the sandstone remained unchanged.The permeability surges observed at different stages are interpreted as resulting from shear-induced reopening of pre-existing fractures and the formation of new shear-failure fractures.A stress-permeability model jointly governed by effective mean stress and deviatoric stress was established.Furthermore,two strategies are proposed for the floor water-inrush disasters prevention,(i)timely backfilling to reduce deviatoric stress,(ii)grouting after the first permeability surge.This work provides insights into stress-seepage behavior in rocks under complex stress evolution and offers new perspectives for identifying potential water inrush pathways in the floor strata of coal seam during longwall mining.
基金supported by the National Youth Top-notch Talent Support Program of China(Grant No.00389335)the National Natural Science Foundation of China(Grant No.52378392)+1 种基金the“Foal Eagle Program”Youth Top-notch Talent Project of Fujian Province(Grant No.00387088)supports are gratefully acknowledged.
文摘Enzyme-Induced Carbonate Precipitation(EICP)is an innovative technique to improve soil strength and reduce permeability.However,the use of EICP for reinforcing underwater sand beds remains largely unexplored.To advance EICP implementation in various geotechnical applications,this paper develops a model box system to investigate the effectiveness of the EICP technique in reinforcing underwater sand beds.An"injection-extraction"system is designed to facilitate the flow of the EICP solution through underwater sand layers.Key parameters,including conductivity,pH,and Ca^(2+)concentration of the solution,are measured and analyzed.Electrical resistivity tomography(ERT)is utilized to evaluate the reinforcement effect in the underwater sand bed.The permeability of the model is tested to verify the feasibility of EICP technology for strengthening underwater sands.Furthermore,scanning electron microscope(SEM)is performed to investigate the growth mechanisms of calcium carbonate(CaCO_(3))crystals.The results show that the permeability of the model decreases from 1.28×10^(-2)m/s to 9.66×10^(-5)m/s,representing a reduction of approximately three orders of magnitude.This verifies that the EICP technology can greatly reduce the permeability of underwater sand beds.With increasing grouting cycles,the resistivity of the underwater sand initially decreases and then increases.This variation in sand resistivity is significantly influenced by the ion concentration in the solution,resulting in marked differences in resistivity at various depths and positions within the sand.The findings from this study offer a theoretical basis for the application of EICP technology in reinforcing seabed foundations and supporting marine infrastructure such as offshore pipelines,wind turbines,and oil platforms.
文摘Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper equations are one of the main and most efficient methods for estimating stem volume to any merchantable limit of a species.There is currently no taper equation for Eucalyptus species in Nigeria.Therefore,this study developed taper equations for E.camaldulensis in northern Nigeria.Data for this study were obtained from a private plantation in Jalingo Local Government Area,Taraba State,Nigeria.68 trees were felled and sectioned into 1-m bolt across the stem to a merchantable limit of 5 cm,which were used as the fitting dataset.An additional 22 trees were felled and used to validate the taper equations for stem volume estimation.Seven taper equations were initially fitted to the dataset using nonlinear least squares.The best taper equation was then refitted using a nonlinear mixed-effects approach and calibrated using diameters of one to five sections from the butt end.The taper equations were numerically integrated to obtain the stem volume,which was compared with empirical volume equations.The result shows that the Kozak(Can J For Res 27(5):619-629.10.1139/x97-011,1997)equation,which included eight parameters,provided the best fit for predicting section diameters for under and over bark.The mixed-effects taper equation(NLME-TE)explained most stem diameter variations in the fitting dataset(pseudo-R2:0.986-0.987;RMSE:0.547-0.578 cm)without substantial residual trends.The validation showed that the prediction accuracy of the integrated NLME-TE improved as the number of sectional diameter measurements increased,with at least a 35%reduction in volume estimate error.For practical implementation,two calibration sectional diameter measurements taken from the butt end per tree are recommended.This approach would reduce measurement effort and cost while improving model performance.
基金the financial support from the Key Project of Shaanxi Provincial Natural Science Foundation-Key Project of Laboratory(2025SYS-SYSZD-117)the Natural Science Basic Research Program of Shaanxi(2025JCYBQN-125)+8 种基金Young Talent Fund of Xi'an Association for Science and Technology(0959202513002)the Key Industrial Chain Technology Research Program of Xi'an(24ZDCYJSGG0048)the Key Research and Development Program of Xianyang(L2023-ZDYF-SF-077)Postdoctoral Fellowship Program of CPSF(GZC20241442)Shaanxi Postdoctoral Science Foundation(2024BSHSDZZ070)Research Funds for the Interdisciplinary Projects,CHU(300104240913)the Fundamental Research Funds for the Central Universities,CHU(300102385739,300102384201,300102384103)the Scientific Innovation Practice Project of Postgraduate of Chang'an University(300103725063)the financial support from the Australian Research Council。
文摘Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.
基金Support by Sichuan Science and Technology Program[2023YFSY0026,2023YFH0004]Guangzhou Huashang University[2024HSZD01,HS2023JYSZH01].
文摘Soft-tissue motion introduces significant challenges in robotic teleoperation,especially in medical scenarios where precise target tracking is critical.Latency across sensing,computation,and actuation chains leads to degraded tracking performance,particularly around high-acceleration segments and trajectory inflection points.This study investigates machine learning-based predictive compensation for latency mitigation in soft-tissue tracking.Three models—autoregressive(AR),long short-term memory(LSTM),and temporal convolutional network(TCN)—were implemented and evaluated on both synthetic and real datasets.By aligning the prediction horizon with the end-to-end system delay,we demonstrate that prediction-based compensation significantly reduces tracking errors.Among the models,TCN achieved superior robustness and accuracy on complex motion patterns,particularly in multi-step prediction tasks,and exhibited better latency–horizon compatibility.The results suggest that TCN is a promising candidate for real-time latency compensation in teleoperated robotic systems involving dynamic soft-tissue interaction.
基金funded by the National Natural Science Foundation of China (32172108 and 32301940)the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology (2023QNRC001)+2 种基金the China Postdoctoral Science Foundation (2022M710489)the Chinese Scholarship Council (202310930003)the National Key Research and Development Program of China (2022YFD2301004)。
文摘The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses substantial challenges.Issues such as water scarcity,energy crises,escalating greenhouse gas emissions,and diminishing farm profitability threaten longterm agricultural sustainability.In response,we applied a holistic food–carbon–nitrogen–water–energy–profit (FCNWEP)nexus framework to comprehensively assess the sustainability of distinct crop management strategies across three subsites in Central China.Field experiments were conducted in Hubei and Hunan provinces from 2017 to 2021 using a widely adopted elite super hybrid rice cultivar (Y-liangyou 900).Four crop management treatments were implemented:a control(CK,0 kg N ha^(-1)),conventional crop management (CCM,210–250 kg N ha^(-1),7:3 basal:mid-tiller fertilizer ratio),and two integrated crop management (ICM) treatments (ICM1,180–210 kg N ha^(-1),5:2:3 basal:mid-tiller:panicle initiation fertilizer ratio;ICM2,240–270 kg N ha^(-1),5:2:2:1 basal:mid-tiller:panicle initiation:flowering fertilizer ratio).Variables assessed included grain yield,carbon footprint,nitrogen footprint,water footprint,energy footprint,nitrogen use efficiency,and economic benefits.Our results showed significant yield variations,with ICM2 consistently outperforming CCM and ICM1across all three sites.In Jingzhou,Suizhou,and Changsha,ICM2’s grain yield was 30.2,24.7,and 13.3%higher than CCM,respectively.Net profits under ICM2 exceeded those of CCM and ICM1 by 31.8 and 115.2%in Jingzhou,32.2 and 109.9%in Suizhou,and 15.4 and 34.0%in Changsha,respectively.Integrated crop management,particularly ICM2,demonstrated improved nitrogen and energy use efficiency,leading to reduced carbon,nitrogen,water,and energy footprints.Overall,composite sustainability scores derived from the FCNWEP framework indicated that both ICM2 and ICM1 exhibited higher sustainability levels compared to CCM.This study provides valuable insights into practical management methodologies and offers recommendations for enhancing agricultural sustainability.
基金supported by the National Natural Science Foundation of China(Grant Nos.52378392,52408356)the Foal Eagle Program Youth Top-notch Talent Project of Fujian Province,China(Grant No.00387088).
文摘Although machine learning models have achieved high enough accuracy in predicting shield position deviations,their“black box”nature makes the prediction mechanisms and decision-making processes opaque,leading to weaker explanations and practicability.This study introduces a novel explainable deep learning framework comprising the Informer model with enhanced attention mechanisms(EAMInfor)and deep learning important features(DeepLIFT),aimed at improving the prediction accuracy of shield position deviations and providing interpretability for predictive results.The EAMInfor model attempts to integrate channel attention,spatial attention,and simple attention modules to improve the Informer model's performance.The framework is tested with the four different geological conditions datasets generated from the Xiamen metro line 3,China.Results show that the EAMInfor model outperforms the traditional Informer and comparison models.The analysis with the DeepLIFT method indicates that the push thrust of push cylinder and the earth chamber pressure are the most significant features,while the stroke length of the push cylinder demonstrated lower importance.Furthermore,the variation trends in the significance of data points within input sequences exhibit substantial differences between single and composite strata.This framework not only improves predictive accuracy but also strengthens the credibility and reliability of the results.
基金funded by Guangzhou Huashang University(2024HSZD01,HS2023JYSZH01).
文摘Graph Neural Networks(GNNs),as a deep learning framework specifically designed for graph-structured data,have achieved deep representation learning of graph data through message passing mechanisms and have become a core technology in the field of graph analysis.However,current reviews on GNN models are mainly focused on smaller domains,and there is a lack of systematic reviews on the classification and applications of GNN models.This review systematically synthesizes the three canonical branches of GNN,Graph Convolutional Network(GCN),Graph Attention Network(GAT),and Graph Sampling Aggregation Network(GraphSAGE),and analyzes their integration pathways from both structural and feature perspectives.Drawing on representative studies,we identify three major integration patterns:cascaded fusion,where heterogeneous modules such as Convolutional Neural Network(CNN),Long Short-Term Memory(LSTM),and GraphSAGE are sequentially combined for hierarchical feature learning;parallel fusion,where multi-branch architectures jointly encode complementary graph features;and feature-level fusion,which employs concatenation,weighted summation,or attention-based gating to adaptively merge multi-source embeddings.Through these patterns,integrated GNNs achieve enhanced expressiveness,robustness,and scalability across domains including transportation,biomedicine,and cybersecurity.
基金supported by the National Natural Science Foundation of China(22409065)the Guangdong Basic and Applied Basic Research Foundation(2022A1515011906)+2 种基金the China Postdoctoral Science Foundation(2023M731153)the Research Fund Program of Guangdong Provincial Key Laboratory of Fuel Cell Technologythe Postdoctoral Fellowship Program of CPSF(GZC20230868).
文摘The application of conventional manganese dioxide(MnO_(2))materials in sodium-ion supercapacitors(Na-SCs)is considerably limited by their low conductivity and structural instability.Biomimetic morphology engineering can optimize the electrochemical performance of MnO_(2).Here,based on the metal-organic frameworks(MOFs)-derived method and electrochemical reconstruction,a coral-like MnO_(2)structure integrated with a functional nitrogen-doped carbon(NC)coating is designed for Na-SC application.The bioinspired coral-like structure captures numerous electrolyte ions and increases the Na+concentration on the electrode surface,which is beneficial for optimizing the Na+transport pathway and accelerating the electrode reaction kinetics.Moreover,the coral-like crosslinked structure effectively enhances the mechanical properties,enabling the maintenance of the structure of MnO_(2)-based electrodes during long-term operation.Furthermore,in/ex-situ characterizations are performed to elucidate the mechanism of lattice transformation during electrochemical phase reconstruction.Additionally,the theoretical calculation and simulation results reveal the ion/electron dynamics in the fabricated electrode.The prepared electrode demonstrates excellent capacitance storage ability(340.7 F g^(−1)at 0.5 A g^(−1))and cycling stability(85.1%capacitance retention after 10,000 cycles).The assembled hybrid device exhibits exceptional life-span(82.0%capacitance retention after 10,000 cycles)and exceptional energy density(36.5 Wh kg^(−1)).This study provides a reliable biomimetic morphology design strategy for MnO_(2)cathodes,paving the way for the fabrication of high-performance Na-SCs.
基金supported by the National Nature Science Foundation of China(Grant Nos.32171307,12372307,12172089,61821002 and 82102567)the Basic Research Plan Natural Science Foundation of Jiangsu Province(Grant No.BK20232023)+1 种基金the Nature Science Foundation of Jiangsu Province(Grant No.BK20200144)the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.5007032303).
文摘The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the OA meniscus is very important.This study aimed to assess the quasi-static nonlinear mechanical behaviours of the three zones of the OA meniscus by a proposed meso-indentation method,and further to investigate its nonlinear mechanical responses under the stance.Four pairs of menisci were harvested from OA patients during total knee arthroplasty.One pair of the menisci was first used for the histological analysis.Binocular fringe projection technology was then employed to reconstruct the morphology of the other three pairs of the menisci.Subsequently,a meso-indentation method was proposed to characterize the nonlinear behaviors of the meniscus zones,moreover,the hyperelastic model(HEM)together with the Hertz’s elastic model(EM)was used to fit the indentation force-depth curves of the meniscus zones.Furthermore,the fitted HEM and EM materials parameters were used to simulate the mechanical response of the meniscus in the stance by two simplified meniscus models.The results showed that the type III collagen widely existed in the OA menisci,and the red-white zone exhibited the best mechanical performance,and the 3-term Mooney-Rivlin model was the best descriptor for the nonlinear mechanical characterization of the three zones.Moreover,the stress or strain distributions of the simplified meniscus models differed significantly between the HEM and EM under the stance,and the EM underestimated the mechanical behaviours of the meniscus.The current work generally provides a novel testing method to study the nonlinear mechanical behaviour of soft biological materials,and is specifically helpful to understand the nonlinear mechanical behaviour of the OA meniscus for which the HEM should be used in the meniscus-related biomechanical studies.
基金supported by a National Health and Medical Research Council(NHMRC)Investigator Grant Emerging Leadership Level 1(Grant No.2017012).
文摘Purpose We aimed to investigate the effects of running shoe longitudinal bending stiffness(LBS)and midsole energy return on running economy and ankle mechanics and energetics.Methods PubMed,Scopus,SPORTDiscus,Embase,CINAHL,and Web of Science were systematically searched for this meta-analysis.Crossover studies comparing the effects of running shoe LBS and/or midsole energy return on at least 1 of the following outcomes:running economy,ankle plantarflexion moment,work,power,or angular velocity were included.Results Of the 2453 studies screened,48 were included(n=878).Results indicated that advanced footwear technologies(AFTs)significantly reduced oxygen consumption(standardized mean difference=–0.44,95%confidence interval:–0.60 to–0.28),p<0.001)as well as peak ankle moments and positive/negative ankle work and power.However,neither LBS nor midsole energy return alone significantly affected oxygen consumption,ankle moments,positive and negative work,or positive power.The effects of AFTs were moderated by the training status and speed of the runner.The quality of evidence for all outcomes were low or very low for all outcomes except the effect of LBS on negative ankle work.Conclusion AFT may improve running economy by minimizing ankle moments,work,and power.The absence of significant independent effects of LBS and midsole energy return suggests that the benefits of AFTs arise from the interaction of these properties.Further research is necessary to understand the mechanisms for improved running performance in AFTs.
文摘Parkinson's disease(PD) has a complex and multifactorial pathophysiology. Various studies, conducted both in pre-clinical models and PD patients, have reported a link between the disruption of calcium(Ca^(2+)) homeostasis and the subsequent development of PD. Ca^(2+) regulation is crucial for neuronal survival, differentiation,exocytosis at synapses,gene transcription,and proliferation.
文摘This review focuses on the diagnostic algorithm for nonobstructive azoospermia(NOA),a significant male factor contributing to infertility.NOA,characterized by the absence of sperm in the ejaculate,requires a systematic diagnostic approach to identify reversible conditions,genetic factors,and prognosis for achieving pregnancy.The diagnostic pathway involves semen analysis and a comprehensive evaluation for hormonal deficiencies,anatomical abnormalities,and genetic factors.The importance of medical history,physical examination,endocrine evaluation,imaging,and genetic testing is emphasized.This review highlights the significance of differentiating NOA from obstructive azoospermia(OA)and outlines key considerations for effective management,including surgical sperm retrieval and assisted reproductive techniques.Testicular biopsy is discussed as a definitive method to distinguish obstructive cases from nonobstructive cases,providing valuable prognostic information.Overall,a thorough and systematic diagnostic approach is essential for the effective management of men suspected with NOA,offering insights into potential treatment options and reproductive outcomes.
