Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(M...Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI methodologies.Methods A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health outcomes.AI methodologies were summarized and categorized to identify synergies,patterns,and trends informing future research.Additionally,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader application.Results The review included 24 studies that met the predetermined eligibility criteria.AI models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention outcomes.Most studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test data.Comparisons of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and task.An increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making tasks.Six key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing injuries.Conclusion The scoping review highlights the potential of AI methodologies for advancing PA interventions.As the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improvements in PA interventions and fostering overall well-being.展开更多
In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique ...In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of slopes.Seawater contains magnesium ions(Mg^(2+))with a higher concentration than calcium ions(Ca^(2+));therefore,Mg^(2+)and Ca^(2+)were used together for bio-cementation in this study at various Mg^(2+)/Ca^(2+)ratios as the microbially induced magnesium and calcium precipitation(MIMCP)treatment.Slope angles,surface strengths,precipitation contents,major phases,and microscopic characteristics of precipitation were used to evaluate the treatment effects.Results showed that the MIMCP treatment markedly enhanced the erosion resistance of slopes.Decreased Mg^(2+)/Ca^(2+)ratios resulted in a smaller change in angles and fewer soil losses,especially the Mg^(2+)concentration below 0.2 M.The decreased Mg^(2+)/Ca^(2+)ratio achieved increased precipitation contents,which contributed to better erosion resistance and higher surface strengths.Additionally,the production of aragonite would benefit from elevated Mg^(2+)concentrations and a higher Ca^(2+)concentration led to more nesquehonite in magnesium precipitation crystals.The slopes with an initial angle of 53°had worse erosion resistance than the slopes with an initial angle of 35°,but the Mg^(2+)/Ca^(2+)ratios of 0.2:0.8,0.1:0.9,and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great extent.The results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering.展开更多
The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and pla...The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and plays a key role in bathymetry modeling over these regions.The Synthetic Aperture Radar(SAR)altimeters in the missions like CryoSat-2 and Sentinel-3A/3B can relieve waveform contamination that existed in conventional altimeters and provide data with improved accuracy and spatial resolution.In this study,we investigate the potential application of SAR altimetric gravity data in enhancing coastal bathymetry,where the effects on local bathymetry modeling introduced from SAR altimetry data are quantified and evaluated.Furthermore,we study the effects on bathymetry modeling by using different scale factor calculation approaches,where a partition-wise scheme is implemented.The numerical experiment over the South Sandwich Islands near Antarctica suggests that using SARbased altimetric gravity data improves local coastal bathymetry modeling,compared with the model calculated without SAR altimetry data by a magnitude of 3:55 m within 10 km of offshore areas.Moreover,by using the partition-wise scheme for scale factor calculation,the quality of the coastal bathymetry model is improved by 7.34 m compared with the result derived from the traditional method.These results indicate the superiority of using SAR altimetry data in coastal bathymetry inversion.展开更多
Background:Mangrove forests are a significant contributor to the global carbon cycle,and the accurate estimation of their gross primary productivity(GPP)is essential for understanding the carbon budget within blue car...Background:Mangrove forests are a significant contributor to the global carbon cycle,and the accurate estimation of their gross primary productivity(GPP)is essential for understanding the carbon budget within blue carbon ecosystems.Little attention has been given to the investigation of spatiotemporal patterns and ecological variations within mangrove ecosystems,as well as the quantitative analysis of the influence of geo-environmental factors on time-series estimations of mangrove GPP.Methods:This study explored the spatiotemporal dynamics of mangrove GPP from 2000 to 2020 in Gaoqiao Mangrove Reserve,China.A leaf area index(LAI)-based light-use efficiency(LUE)model was combined with Landsat data on Google Earth Engine(GEE)to reveal the variations in mangrove GPP using the Mann-Kendall(MK)test and Theil-Sen median trend.Moreover,the spatiotemporal patterns and ecological variations in mangrove ecosystems across regions were explored using four landscape indicators.Furthermore,the effects of six geo-environmental factors(species distribution,offshore distance,elevation,slope,planar curvature and profile curvature)on GPP were investigated using Geodetector and multi-scale geo-weighted regression(MGWR).Results:The results showed that the mangrove forest in the study area experienced an area loss from 766.26 ha in 2000 to 718.29 ha in 2020,mainly due to the conversion to farming,terrestrial forest and aquaculture zones.Landscape patterns indicated high levels of vegetation aggregation near water bodies and aquaculture zones,and low levels of aggregation but high species diversity and distribution density near building zone.The mean value of mangrove GPP continuously increased from 6.35 g C⋅m^(-2)⋅d^(-1) in 2000 to 8.33 g C⋅m^(-2)⋅d^(-1) in 2020,with 23.21%of areas showing a highly and significantly increasing trend(trend value>0.50).The Geodetector and MGWR analyses showed that species distribution,offshore distance and elevation contributed most to the GPP variations.Conclusions:These results provide guidelines for selecting GPP products,and the combination of Geodetector and MGWR based on multiple geo-environmental factors could quantitatively capture the mode,direction,pathway and intensity of the influencing factors on mangrove GPP variation.The findings provide a foundation for understanding the spatiotemporal dynamics of mangrove GPP at the landscape or regional scale.展开更多
Purpose:Media exaggerations of health research may confuse readers’understanding,erode public trust in science and medicine,and cause disease mismanagement.This study built artificial intelligence(AI)models to automa...Purpose:Media exaggerations of health research may confuse readers’understanding,erode public trust in science and medicine,and cause disease mismanagement.This study built artificial intelligence(AI)models to automatically identify and correct news headlines exaggerating obesity-related research findings.Design/methodology/approach:We searched popular digital media outlets to collect 523 headlines exaggerating obesity-related research findings.The reasons for exaggerations include:inferring causality from observational studies,inferring human outcomes from animal research,inferring distant/end outcomes(e.g.,obesity)from immediate/intermediate outcomes(e.g.,calorie intake),and generalizing findings to the population from a subgroup or convenience sample.Each headline was paired with the title and abstract of the peer-reviewed journal publication covered by the news article.We drafted an exaggeration-free counterpart for each original headline and fined-tuned a BERT model to differentiate between them.We further fine-tuned three generative language models-BART,PEGASUS,and T5 to autogenerate exaggeration-free headlines based on a journal publication’s title and abstract.Model performance was evaluated using the ROUGE metrics by comparing model-generated headlines with journal publication titles.Findings:The fine-tuned BERT model achieved 92.5%accuracy in differentiating between exaggeration-free and original headlines.Baseline ROUGE scores averaged 0.311 for ROUGE-1,0.113 for ROUGE-2,0.253 for ROUGE-L,and 0.253 ROUGE-Lsum.PEGASUS,T5,and BART all outperformed the baseline.The best-performing BART model attained 0.447 for ROUGE-1,0.221 for ROUGE-2,0.402 for ROUGE-L,and 0.402 for ROUGE-Lsum.Originality/value:This study demonstrated the feasibility of leveraging AI to automatically identify and correct news headlines exaggerating obesity-related research findings.展开更多
Objective Ureteral lesions caused by impacted ureteral stones are likely to result in postoperative ureteral stricture.On this basis,the study aimed to investigate if dual-energy spectral computed tomography can predi...Objective Ureteral lesions caused by impacted ureteral stones are likely to result in postoperative ureteral stricture.On this basis,the study aimed to investigate if dual-energy spectral computed tomography can predict ureteral hardening caused by impacted stones and to explore the relationship between different types of ureteral lesions and the risk of ureteral stricture.Methods This prospective study collected data of 93 patients with impacted stones from hospital automation system during January 2018 to October 2019.They underwent an abdominal scan on a dual-energy spectral computed tomography.During surgery,the operator used ureteroscopy to identify ureteral lesions,which were classified into four categories:edema,polyps,pallor,and hardening.Seven months later,90 patients were reviewed for the degree of hydronephrosis.Results Endoscopic observations revealed 38(41%)cases of ureteral edema,20(22%)cases of polyps,13(14%)cases of pallor,and 22(24%)cases of hardening.There were significant differences in hydronephrosis,the period of impaction,the calcium concentration of the ureter,and the slope of the spectral Hounsfield unit curve between the four groups.After that,we evaluated the factors associated with ureteral hardening and found that the calcium concentration of the ureter and hydronephrosis remained independent predictors of ureteral hardening.Receiver operating characteristic curve analysis showed that 5.3 mg/cm^(3)calcium concentration of the ureter is an optimal cut-off value to predict ureteral hardening.The result of follow-up showed that 80 patients had complete remission of hydronephrosis,with a complete remission rate of 61.9%(13/21)in the hardening group and 97.1%(67/69)in the non-hardening group(p<0.001).Conclusion Calcium concentration of the ureter is an independent predictor of ureteral hardening.Patients with ureteral hardening have more severe hydronephrosis after ureteroscopic lithotripsy.When the calcium concentration of the ureter is less than 5.3 mg/cm^(3),ureteral lesions should be actively treated.展开更多
The oxygen reduction reaction(ORR)electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles(NPs)on a porous carbon support with large surface area.Howev...The oxygen reduction reaction(ORR)electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles(NPs)on a porous carbon support with large surface area.However,such catalysts are often obtained by constructing porous carbon support followed by depositing Pt and its alloy NPs inside the pores,in which the migration and agglomeration of Pt NPs are inevitable under harsh operating conditions owing to the relatively weak interaction between NPs and carbon support.Here we develop a facile electrospinning strategy to in-situ prepare small-sized PtZn NPs supported on porous nitrogen-doped carbon nanofibers.Electrochemical results demonstrate that the as-prepared PtZn alloy catalyst exhibits excellent initial ORR activity with a half-wave potential(E_(1/2))of 0.911 V versus reversible hydrogen electrode(vs.RHE)and enhanced durability with only decreasing 11 mV after 30,000 potential cycles,compared to a more significant drop of 24 mV in E_(1/2)of Pt/C catalysts(after 10,000 potential cycling).Such a desirable performance is ascribed to the created triple-phase reaction boundary assisted by the evaporation of Zn and strengthened interaction between nanoparticles and the carbon support,inhibiting the migration and aggregation of NPs during the ORR.展开更多
Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensiv...Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensive studies in the past decades. However, how a non-Hermitian system responses to an electric field and what is the connection of the response to the Chern number defined via the non-Hermitian Hamiltonian remains barely explored. In this paper, focusing on a k-dependent decay rate, we address this issue by studying the response of such a non-Hermitian Chern insulator to an external electric field. To this aim, we first derive an effective non-Hermitian Hamiltonian to describe the system and give a specific form of k-dependent decay rate. Then we calculate the response of the non-Hermitian system to a constant electric field.We observe that the environment leads the Hall conductance to be a weighted integration of curvature of the ground band and hence the conductance is no longer quantized in general. And the environment induces a delay in the response of the system to the electric field. A discussion on the validity of the non-Hermitian model compared with the master equation description is also presented.展开更多
5-Methylcytosine(m5C)methylation contributes to the development and progression of various malignant tumors.This study aimed to explore the potential role of m5C methylation regulators(m5CMRs)in head and neck squamous...5-Methylcytosine(m5C)methylation contributes to the development and progression of various malignant tumors.This study aimed to explore the potential role of m5C methylation regulators(m5CMRs)in head and neck squamous cell carcinoma(HNSCC).Methods:The transcription data of HNSCC samples were obtained from The Cancer Genome Atlas(TCGA)and the Gene Expression Omnibus(GEO)databases.Subsequently,the m5C patterns in HNSCC were evaluated based on 14 m5CMRs.Then,the m5Cscore was developed to quantify m5C patterns by using principal component analysis(PCA)algorithms.Two single-cell RNA sequencing datasets and various methods were employed to assess the prognostic value and sensitivity to immunotherapy.Finally,key prognostic m5CMRs were identified using univariate COX regression analysis,and their clinical significance was validated based on the Human Protein Atlas(HPA)database and by using immunohistochemistry.Results:Two distinct m5C clusters were identified.m5C cluster A is characterized by an immune-activated microenvironment and is associated with a favorable prognosis.Notable differences were observed in prognosis,immune infiltration,and immunotherapy response between the high-and low-m5Cscore groups.Patients in the high-m5Cscore group exhibited high TMB,which is correlated with poor prognosis.The m5Cscore of epithelial cells in HNSCC was higher than that in other cells.Key prognostic m5CMRs,including NSUN2,DNMT3B,ALKBH1,and Y-Box Binding Protein 1(YBX1),were associated with poor prognosis.Conclusion:Our research indicates that in head and neck squamous cell carcinoma,the m5C modification profoundly affects the TME’s diversity and complexity,influencing prognosis and the success of immunotherapy.Targeting m5C regulatory elements may be a new method for enhancing the efficacy of immunotherapy in HNSCC.展开更多
Based on data from the Jilin Water Diversion Tunnels from the Songhua River(China),an improved and real-time prediction method optimized by multi-algorithm for tunnel boring machine(TBM)cutter-head torque is presented...Based on data from the Jilin Water Diversion Tunnels from the Songhua River(China),an improved and real-time prediction method optimized by multi-algorithm for tunnel boring machine(TBM)cutter-head torque is presented.Firstly,a function excluding invalid and abnormal data is established to distinguish TBM operating state,and a feature selection method based on the SelectKBest algorithm is proposed.Accordingly,ten features that are most closely related to the cutter-head torque are selected as input variables,which,in descending order of influence,include the sum of motor torque,cutter-head power,sum of motor power,sum of motor current,advance rate,cutter-head pressure,total thrust force,penetration rate,cutter-head rotational velocity,and field penetration index.Secondly,a real-time cutterhead torque prediction model’s structure is developed,based on the bidirectional long short-term memory(BLSTM)network integrating the dropout algorithm to prevent overfitting.Then,an algorithm to optimize hyperparameters of model based on Bayesian and cross-validation is proposed.Early stopping and checkpoint algorithms are integrated to optimize the training process.Finally,a BLSTMbased real-time cutter-head torque prediction model is developed,which fully utilizes the previous time-series tunneling information.The mean absolute percentage error(MAPE)of the model in the verification section is 7.3%,implying that the presented model is suitable for real-time cutter-head torque prediction.Furthermore,an incremental learning method based on the above base model is introduced to improve the adaptability of the model during the TBM tunneling.Comparison of the prediction performance between the base and incremental learning models in the same tunneling section shows that:(1)the MAPE of the predicted results of the BLSTM-based real-time cutter-head torque prediction model remains below 10%,and both the coefficient of determination(R^(2))and correlation coefficient(r)between measured and predicted values exceed 0.95;and(2)the incremental learning method is suitable for realtime cutter-head torque prediction and can effectively improve the prediction accuracy and generalization capacity of the model during the excavation process.展开更多
[Objective] To understand the effect of nitrogen application on dry matter accumulation and allocation dynamics in broomcorn millet. [Method] The accumulation and distribution of dry matter were studied using cultivar...[Objective] To understand the effect of nitrogen application on dry matter accumulation and allocation dynamics in broomcorn millet. [Method] The accumulation and distribution of dry matter were studied using cultivars Jin Shu 7 and Huang Mizi at different levels of nitrogen fertilizer at the jointing stage. [Result] The results showed that increasing N application led to the increase of green leaf area and the delay of leaf senescence, which was beneficial to the accumulation of dry matter.Appropriate nitrogen application(90 kg/hm2) could coordinate the translocation rate of dry matter among different plant parts, thereby enhancing the yield of broomcorn millet; among different organs, the contribution rate of stem to kernel was greater than that of leaf to kernel; there was obvious correlation between dry matter and yield. For Jin Shu 7, leaf area and dry weight of spike showed significant negative correlation with yield. [Conclusion] The formation of grain yield of broomcorn millet involved the accumulation and allocation of dry matter, the appropriate amount of nitrogen application(90 kg/hm2) could improve the rates of translocation and contribution of dry matter, thereby promoting the yield of broomcorn millet.展开更多
As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals de...As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals development is critical to adapt the long-term stable operation.In this paper,the volumetric mass transfer coefficient,gas holdup and bubble size in a gas-liquid up-flow column are studied with two kinds of internals.The gas holdup and volumetric mass transfer coefficient increase by 120% and 42% when the fractal dimension of bubbles increases from 0.56 to 2.56,respectively.The enhanced mass transfer processing may improve the coke suppression ability in the slurry reactor for residual oil treatment.The results can be useful for the exploration of reacting conditions,scale-up strategies,and oil adaptability.This work is valuable for the design of reactor systems and technological processes.展开更多
Dear editor,Deep reinforcement learning(DRL),combining the perception capability of deep learning(DL)and the decision-making capability of reinforcement learning(RL)[1],has been widely investigated for autonomous driv...Dear editor,Deep reinforcement learning(DRL),combining the perception capability of deep learning(DL)and the decision-making capability of reinforcement learning(RL)[1],has been widely investigated for autonomous driving decision-making tasks.In this letter,Fund:supported in part by the National Natural Science Foundation of China(NSFC)(62173325);the Beijing Municipal Natural Science Foundation(L191002).展开更多
Jujube(Ziziphus jujuba Mill.)is an important perennial fruit tree with a range of interesting horticultural traits.It was domesticated from wild jujube(Ziziphus acidojujuba),but the genomic variation dynamics and gene...Jujube(Ziziphus jujuba Mill.)is an important perennial fruit tree with a range of interesting horticultural traits.It was domesticated from wild jujube(Ziziphus acidojujuba),but the genomic variation dynamics and genetic changes underlying its horticultural traits during domestication are poorly understood.Here,we report a comprehensive genome variation map based on the resequencing of 350 accessions,including wild,semi-wild and cultivated jujube plants,at a>15×depth.Using the combination of a genome-wide association study(GWAS)and selective sweep analysis,we identified several candidate genes potentially involved in regulating seven domestication traits in jujube.For fruit shape and kernel shape,we integrated the GWAS approach with transcriptome profiling data,expression analysis and the transgenic validation of a candidate gene to identify a causal gene,ZjFS3,which encodes an ethyleneresponsive transcription factor.Similarly,we identified a candidate gene for bearing-shoot length and the number of leaves per bearing shoot and two candidate genes for the seed-setting rate using GWAS.In the selective sweep analysis,we also discovered several putative genes for the presence of prickles on bearing shoots and the postharvest shelf life of fleshy fruits.This study outlines the genetic basis of jujube domestication and evolution and provides a rich genomic resource for mining other horticulturally important genes in jujube.展开更多
文摘Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI methodologies.Methods A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health outcomes.AI methodologies were summarized and categorized to identify synergies,patterns,and trends informing future research.Additionally,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader application.Results The review included 24 studies that met the predetermined eligibility criteria.AI models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention outcomes.Most studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test data.Comparisons of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and task.An increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making tasks.Six key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing injuries.Conclusion The scoping review highlights the potential of AI methodologies for advancing PA interventions.As the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improvements in PA interventions and fostering overall well-being.
基金funded by the National Natural Science Foundation of China(Grant No.51578147)Fundamental Research Funds for the Central Universities(Grant No.2242020R20025)Ningxia Science and Technology Department(Grant No.2020BFG02014).
文摘In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of slopes.Seawater contains magnesium ions(Mg^(2+))with a higher concentration than calcium ions(Ca^(2+));therefore,Mg^(2+)and Ca^(2+)were used together for bio-cementation in this study at various Mg^(2+)/Ca^(2+)ratios as the microbially induced magnesium and calcium precipitation(MIMCP)treatment.Slope angles,surface strengths,precipitation contents,major phases,and microscopic characteristics of precipitation were used to evaluate the treatment effects.Results showed that the MIMCP treatment markedly enhanced the erosion resistance of slopes.Decreased Mg^(2+)/Ca^(2+)ratios resulted in a smaller change in angles and fewer soil losses,especially the Mg^(2+)concentration below 0.2 M.The decreased Mg^(2+)/Ca^(2+)ratio achieved increased precipitation contents,which contributed to better erosion resistance and higher surface strengths.Additionally,the production of aragonite would benefit from elevated Mg^(2+)concentrations and a higher Ca^(2+)concentration led to more nesquehonite in magnesium precipitation crystals.The slopes with an initial angle of 53°had worse erosion resistance than the slopes with an initial angle of 35°,but the Mg^(2+)/Ca^(2+)ratios of 0.2:0.8,0.1:0.9,and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great extent.The results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering.
基金supported by the National Natural Science Foundation of China(No.42004008)the Natural Science Foundation of Jiangsu Province,China(No.BK20190498)+1 种基金the Fundamental Research Funds for the Central Universities(No.B220202055)the State Scholarship Fund from Chinese Scholarship Council(No.201306270014).
文摘The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and plays a key role in bathymetry modeling over these regions.The Synthetic Aperture Radar(SAR)altimeters in the missions like CryoSat-2 and Sentinel-3A/3B can relieve waveform contamination that existed in conventional altimeters and provide data with improved accuracy and spatial resolution.In this study,we investigate the potential application of SAR altimetric gravity data in enhancing coastal bathymetry,where the effects on local bathymetry modeling introduced from SAR altimetry data are quantified and evaluated.Furthermore,we study the effects on bathymetry modeling by using different scale factor calculation approaches,where a partition-wise scheme is implemented.The numerical experiment over the South Sandwich Islands near Antarctica suggests that using SARbased altimetric gravity data improves local coastal bathymetry modeling,compared with the model calculated without SAR altimetry data by a magnitude of 3:55 m within 10 km of offshore areas.Moreover,by using the partition-wise scheme for scale factor calculation,the quality of the coastal bathymetry model is improved by 7.34 m compared with the result derived from the traditional method.These results indicate the superiority of using SAR altimetry data in coastal bathymetry inversion.
基金This work was supported by Guangdong Basic and Applied Basic Research Foundation(2019A1515010741 and 2021A1515110910)Guangdong Regional Joint Fund-Youth Fund(2020A1515111142)Shenzhen Science and Technology Program(JCYJ20210324093210029).
文摘Background:Mangrove forests are a significant contributor to the global carbon cycle,and the accurate estimation of their gross primary productivity(GPP)is essential for understanding the carbon budget within blue carbon ecosystems.Little attention has been given to the investigation of spatiotemporal patterns and ecological variations within mangrove ecosystems,as well as the quantitative analysis of the influence of geo-environmental factors on time-series estimations of mangrove GPP.Methods:This study explored the spatiotemporal dynamics of mangrove GPP from 2000 to 2020 in Gaoqiao Mangrove Reserve,China.A leaf area index(LAI)-based light-use efficiency(LUE)model was combined with Landsat data on Google Earth Engine(GEE)to reveal the variations in mangrove GPP using the Mann-Kendall(MK)test and Theil-Sen median trend.Moreover,the spatiotemporal patterns and ecological variations in mangrove ecosystems across regions were explored using four landscape indicators.Furthermore,the effects of six geo-environmental factors(species distribution,offshore distance,elevation,slope,planar curvature and profile curvature)on GPP were investigated using Geodetector and multi-scale geo-weighted regression(MGWR).Results:The results showed that the mangrove forest in the study area experienced an area loss from 766.26 ha in 2000 to 718.29 ha in 2020,mainly due to the conversion to farming,terrestrial forest and aquaculture zones.Landscape patterns indicated high levels of vegetation aggregation near water bodies and aquaculture zones,and low levels of aggregation but high species diversity and distribution density near building zone.The mean value of mangrove GPP continuously increased from 6.35 g C⋅m^(-2)⋅d^(-1) in 2000 to 8.33 g C⋅m^(-2)⋅d^(-1) in 2020,with 23.21%of areas showing a highly and significantly increasing trend(trend value>0.50).The Geodetector and MGWR analyses showed that species distribution,offshore distance and elevation contributed most to the GPP variations.Conclusions:These results provide guidelines for selecting GPP products,and the combination of Geodetector and MGWR based on multiple geo-environmental factors could quantitatively capture the mode,direction,pathway and intensity of the influencing factors on mangrove GPP variation.The findings provide a foundation for understanding the spatiotemporal dynamics of mangrove GPP at the landscape or regional scale.
文摘Purpose:Media exaggerations of health research may confuse readers’understanding,erode public trust in science and medicine,and cause disease mismanagement.This study built artificial intelligence(AI)models to automatically identify and correct news headlines exaggerating obesity-related research findings.Design/methodology/approach:We searched popular digital media outlets to collect 523 headlines exaggerating obesity-related research findings.The reasons for exaggerations include:inferring causality from observational studies,inferring human outcomes from animal research,inferring distant/end outcomes(e.g.,obesity)from immediate/intermediate outcomes(e.g.,calorie intake),and generalizing findings to the population from a subgroup or convenience sample.Each headline was paired with the title and abstract of the peer-reviewed journal publication covered by the news article.We drafted an exaggeration-free counterpart for each original headline and fined-tuned a BERT model to differentiate between them.We further fine-tuned three generative language models-BART,PEGASUS,and T5 to autogenerate exaggeration-free headlines based on a journal publication’s title and abstract.Model performance was evaluated using the ROUGE metrics by comparing model-generated headlines with journal publication titles.Findings:The fine-tuned BERT model achieved 92.5%accuracy in differentiating between exaggeration-free and original headlines.Baseline ROUGE scores averaged 0.311 for ROUGE-1,0.113 for ROUGE-2,0.253 for ROUGE-L,and 0.253 ROUGE-Lsum.PEGASUS,T5,and BART all outperformed the baseline.The best-performing BART model attained 0.447 for ROUGE-1,0.221 for ROUGE-2,0.402 for ROUGE-L,and 0.402 for ROUGE-Lsum.Originality/value:This study demonstrated the feasibility of leveraging AI to automatically identify and correct news headlines exaggerating obesity-related research findings.
文摘Objective Ureteral lesions caused by impacted ureteral stones are likely to result in postoperative ureteral stricture.On this basis,the study aimed to investigate if dual-energy spectral computed tomography can predict ureteral hardening caused by impacted stones and to explore the relationship between different types of ureteral lesions and the risk of ureteral stricture.Methods This prospective study collected data of 93 patients with impacted stones from hospital automation system during January 2018 to October 2019.They underwent an abdominal scan on a dual-energy spectral computed tomography.During surgery,the operator used ureteroscopy to identify ureteral lesions,which were classified into four categories:edema,polyps,pallor,and hardening.Seven months later,90 patients were reviewed for the degree of hydronephrosis.Results Endoscopic observations revealed 38(41%)cases of ureteral edema,20(22%)cases of polyps,13(14%)cases of pallor,and 22(24%)cases of hardening.There were significant differences in hydronephrosis,the period of impaction,the calcium concentration of the ureter,and the slope of the spectral Hounsfield unit curve between the four groups.After that,we evaluated the factors associated with ureteral hardening and found that the calcium concentration of the ureter and hydronephrosis remained independent predictors of ureteral hardening.Receiver operating characteristic curve analysis showed that 5.3 mg/cm^(3)calcium concentration of the ureter is an optimal cut-off value to predict ureteral hardening.The result of follow-up showed that 80 patients had complete remission of hydronephrosis,with a complete remission rate of 61.9%(13/21)in the hardening group and 97.1%(67/69)in the non-hardening group(p<0.001).Conclusion Calcium concentration of the ureter is an independent predictor of ureteral hardening.Patients with ureteral hardening have more severe hydronephrosis after ureteroscopic lithotripsy.When the calcium concentration of the ureter is less than 5.3 mg/cm^(3),ureteral lesions should be actively treated.
基金This work was financially supported by National Key Research and Development Program(2018YFB1502503).
文摘The oxygen reduction reaction(ORR)electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles(NPs)on a porous carbon support with large surface area.However,such catalysts are often obtained by constructing porous carbon support followed by depositing Pt and its alloy NPs inside the pores,in which the migration and agglomeration of Pt NPs are inevitable under harsh operating conditions owing to the relatively weak interaction between NPs and carbon support.Here we develop a facile electrospinning strategy to in-situ prepare small-sized PtZn NPs supported on porous nitrogen-doped carbon nanofibers.Electrochemical results demonstrate that the as-prepared PtZn alloy catalyst exhibits excellent initial ORR activity with a half-wave potential(E_(1/2))of 0.911 V versus reversible hydrogen electrode(vs.RHE)and enhanced durability with only decreasing 11 mV after 30,000 potential cycles,compared to a more significant drop of 24 mV in E_(1/2)of Pt/C catalysts(after 10,000 potential cycling).Such a desirable performance is ascribed to the created triple-phase reaction boundary assisted by the evaporation of Zn and strengthened interaction between nanoparticles and the carbon support,inhibiting the migration and aggregation of NPs during the ORR.
基金supported by the National Natural Science Foundation of China (Grant Nos. 12175033 and 12147206)。
文摘Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensive studies in the past decades. However, how a non-Hermitian system responses to an electric field and what is the connection of the response to the Chern number defined via the non-Hermitian Hamiltonian remains barely explored. In this paper, focusing on a k-dependent decay rate, we address this issue by studying the response of such a non-Hermitian Chern insulator to an external electric field. To this aim, we first derive an effective non-Hermitian Hamiltonian to describe the system and give a specific form of k-dependent decay rate. Then we calculate the response of the non-Hermitian system to a constant electric field.We observe that the environment leads the Hall conductance to be a weighted integration of curvature of the ground band and hence the conductance is no longer quantized in general. And the environment induces a delay in the response of the system to the electric field. A discussion on the validity of the non-Hermitian model compared with the master equation description is also presented.
基金supported by grants from the Guangdong Science and Technology Development Fund(Grant No.2019A1515110662).
文摘5-Methylcytosine(m5C)methylation contributes to the development and progression of various malignant tumors.This study aimed to explore the potential role of m5C methylation regulators(m5CMRs)in head and neck squamous cell carcinoma(HNSCC).Methods:The transcription data of HNSCC samples were obtained from The Cancer Genome Atlas(TCGA)and the Gene Expression Omnibus(GEO)databases.Subsequently,the m5C patterns in HNSCC were evaluated based on 14 m5CMRs.Then,the m5Cscore was developed to quantify m5C patterns by using principal component analysis(PCA)algorithms.Two single-cell RNA sequencing datasets and various methods were employed to assess the prognostic value and sensitivity to immunotherapy.Finally,key prognostic m5CMRs were identified using univariate COX regression analysis,and their clinical significance was validated based on the Human Protein Atlas(HPA)database and by using immunohistochemistry.Results:Two distinct m5C clusters were identified.m5C cluster A is characterized by an immune-activated microenvironment and is associated with a favorable prognosis.Notable differences were observed in prognosis,immune infiltration,and immunotherapy response between the high-and low-m5Cscore groups.Patients in the high-m5Cscore group exhibited high TMB,which is correlated with poor prognosis.The m5Cscore of epithelial cells in HNSCC was higher than that in other cells.Key prognostic m5CMRs,including NSUN2,DNMT3B,ALKBH1,and Y-Box Binding Protein 1(YBX1),were associated with poor prognosis.Conclusion:Our research indicates that in head and neck squamous cell carcinoma,the m5C modification profoundly affects the TME’s diversity and complexity,influencing prognosis and the success of immunotherapy.Targeting m5C regulatory elements may be a new method for enhancing the efficacy of immunotherapy in HNSCC.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 52074258, 41941018, and U21A20153)
文摘Based on data from the Jilin Water Diversion Tunnels from the Songhua River(China),an improved and real-time prediction method optimized by multi-algorithm for tunnel boring machine(TBM)cutter-head torque is presented.Firstly,a function excluding invalid and abnormal data is established to distinguish TBM operating state,and a feature selection method based on the SelectKBest algorithm is proposed.Accordingly,ten features that are most closely related to the cutter-head torque are selected as input variables,which,in descending order of influence,include the sum of motor torque,cutter-head power,sum of motor power,sum of motor current,advance rate,cutter-head pressure,total thrust force,penetration rate,cutter-head rotational velocity,and field penetration index.Secondly,a real-time cutterhead torque prediction model’s structure is developed,based on the bidirectional long short-term memory(BLSTM)network integrating the dropout algorithm to prevent overfitting.Then,an algorithm to optimize hyperparameters of model based on Bayesian and cross-validation is proposed.Early stopping and checkpoint algorithms are integrated to optimize the training process.Finally,a BLSTMbased real-time cutter-head torque prediction model is developed,which fully utilizes the previous time-series tunneling information.The mean absolute percentage error(MAPE)of the model in the verification section is 7.3%,implying that the presented model is suitable for real-time cutter-head torque prediction.Furthermore,an incremental learning method based on the above base model is introduced to improve the adaptability of the model during the TBM tunneling.Comparison of the prediction performance between the base and incremental learning models in the same tunneling section shows that:(1)the MAPE of the predicted results of the BLSTM-based real-time cutter-head torque prediction model remains below 10%,and both the coefficient of determination(R^(2))and correlation coefficient(r)between measured and predicted values exceed 0.95;and(2)the incremental learning method is suitable for realtime cutter-head torque prediction and can effectively improve the prediction accuracy and generalization capacity of the model during the excavation process.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-07-12.5-A12)
文摘[Objective] To understand the effect of nitrogen application on dry matter accumulation and allocation dynamics in broomcorn millet. [Method] The accumulation and distribution of dry matter were studied using cultivars Jin Shu 7 and Huang Mizi at different levels of nitrogen fertilizer at the jointing stage. [Result] The results showed that increasing N application led to the increase of green leaf area and the delay of leaf senescence, which was beneficial to the accumulation of dry matter.Appropriate nitrogen application(90 kg/hm2) could coordinate the translocation rate of dry matter among different plant parts, thereby enhancing the yield of broomcorn millet; among different organs, the contribution rate of stem to kernel was greater than that of leaf to kernel; there was obvious correlation between dry matter and yield. For Jin Shu 7, leaf area and dry weight of spike showed significant negative correlation with yield. [Conclusion] The formation of grain yield of broomcorn millet involved the accumulation and allocation of dry matter, the appropriate amount of nitrogen application(90 kg/hm2) could improve the rates of translocation and contribution of dry matter, thereby promoting the yield of broomcorn millet.
基金the National Natural Science Foundation of China(51678238,51722806,51608325,21908057)National Key R&D Program of China(2018YFC1802704,2018YFC1801904)+1 种基金China Postdoctoral Science Foundation funded project(2018M641942)Shanghai Sailing Program(19YF1411800)for financial support.
文摘As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals development is critical to adapt the long-term stable operation.In this paper,the volumetric mass transfer coefficient,gas holdup and bubble size in a gas-liquid up-flow column are studied with two kinds of internals.The gas holdup and volumetric mass transfer coefficient increase by 120% and 42% when the fractal dimension of bubbles increases from 0.56 to 2.56,respectively.The enhanced mass transfer processing may improve the coke suppression ability in the slurry reactor for residual oil treatment.The results can be useful for the exploration of reacting conditions,scale-up strategies,and oil adaptability.This work is valuable for the design of reactor systems and technological processes.
基金supported in part by the National Natural Science Foundation of China(NSFC)(62173325)the Beijing Municipal Natural Science Foundation(L191002).
文摘Dear editor,Deep reinforcement learning(DRL),combining the perception capability of deep learning(DL)and the decision-making capability of reinforcement learning(RL)[1],has been widely investigated for autonomous driving decision-making tasks.In this letter,Fund:supported in part by the National Natural Science Foundation of China(NSFC)(62173325);the Beijing Municipal Natural Science Foundation(L191002).
基金supported by the Key Science and Technology Program of Henan Province(192102110058 and 202102110046)the Key Research Projects of Henan Higher Education Institutions(17A180030).
文摘Jujube(Ziziphus jujuba Mill.)is an important perennial fruit tree with a range of interesting horticultural traits.It was domesticated from wild jujube(Ziziphus acidojujuba),but the genomic variation dynamics and genetic changes underlying its horticultural traits during domestication are poorly understood.Here,we report a comprehensive genome variation map based on the resequencing of 350 accessions,including wild,semi-wild and cultivated jujube plants,at a>15×depth.Using the combination of a genome-wide association study(GWAS)and selective sweep analysis,we identified several candidate genes potentially involved in regulating seven domestication traits in jujube.For fruit shape and kernel shape,we integrated the GWAS approach with transcriptome profiling data,expression analysis and the transgenic validation of a candidate gene to identify a causal gene,ZjFS3,which encodes an ethyleneresponsive transcription factor.Similarly,we identified a candidate gene for bearing-shoot length and the number of leaves per bearing shoot and two candidate genes for the seed-setting rate using GWAS.In the selective sweep analysis,we also discovered several putative genes for the presence of prickles on bearing shoots and the postharvest shelf life of fleshy fruits.This study outlines the genetic basis of jujube domestication and evolution and provides a rich genomic resource for mining other horticulturally important genes in jujube.