Given the difficulty in accurately evaluating the fatigue performance of large composite wind turbine blades(referred to as blades),this paper takes the main beam structure of the blade with a rectangular cross-sectio...Given the difficulty in accurately evaluating the fatigue performance of large composite wind turbine blades(referred to as blades),this paper takes the main beam structure of the blade with a rectangular cross-sectionas the simulation object and establishes a composite laminate rectangular beam structure that simultaneouslyincludes the flange,web,and adhesive layer,referred to as the blade main beam sub-structure specimen,throughthe definition of blade sub-structures.This paper examines the progressive damage evolution law of the compositelaminate rectangular beam utilizing an improved 3D Hashin failure criterion,cohesive zone model,B-K failurecriterion,and computer simulation technology.Under static loading,the layup angle of the anti-shear web hasa close relationship with the static load-carrying capacity of the composite laminate rectangular beam;under fatigueloading,the fatigue damage will first occur in the lower flange adhesive area of the whole composite laminaterectangular beam and ultimately result in the fracture failure of the entire structure.These results provide a theoreticalreference and foundation for evaluating and predicting the fatigue performance of the blade main beamstructure and even the full-size blade.展开更多
The millimeter-Wave(mmWave)communication with the advantages of abundant bandwidth and immunity to interference has been deemed a promising technology to greatly improve network capacity.However,due to such characteri...The millimeter-Wave(mmWave)communication with the advantages of abundant bandwidth and immunity to interference has been deemed a promising technology to greatly improve network capacity.However,due to such characteristics of mmWave,as short transmission distance,high sensitivity to the blockage,and large propagation path loss,handover issues(including trigger condition and target beam selection)become much complicated.In this paper,we design a novel handover scheme to optimize the overall system throughput as well as the total system delay while guaranteeing the Quality of Service(QoS)of each User Equipment(UE).Specifically,the proposed handover scheme called O-MAPPO integrates the Reinforcement Learning(RL)algorithm and optimization theory.The RL algorithm known as Multi-Agent Proximal Policy Optimization(MAPPO)plays a role in determining handover trigger conditions.Further,we propose an optimization problem in conjunction with MAPPO to select the target base station.The aim is to evaluate and optimize the system performance of total throughput and delay while guaranteeing the QoS of each UE after the handover decision is made.The numerical results show the overall system throughput and delay with our method are slightly worse than that with the exhaustive search method but much better than that using another typical RL algorithm Deep Deterministic Policy Gradient(DDPG).展开更多
With the continuous integration of new energy into the power grid,various new attacks continue to emerge and the feature distributions are constantly changing during the deployment of intelligent pumped storage power ...With the continuous integration of new energy into the power grid,various new attacks continue to emerge and the feature distributions are constantly changing during the deployment of intelligent pumped storage power stations.The intrusion detection model trained on the old data is hard to effectively identify new attacks,and it is difficult to update the intrusion detection model in time when lacking data.To solve this issue,by using model-based transfer learning methods,in this paper we propose a convolutional neural network(CNN)based transfer online sequential extreme learning machine(TOS-ELM)scheme to enable the online intrusion detection,which is called CNN-TOSELM in this paper.In our proposed scheme,we use pre-trained CNN to extract the characteristics of the target domain data as input,and then build online learning classifier TOS-ELM to transfer the parameter of the ELM classifier of the source domain.Experimental results show the proposed CNNTOSELM scheme can achieve better detection performance and extremely short model update time for intelligent pumped storage power stations.展开更多
We analyze the error of large-eddy simulation(LES)in wall pressure fluctuation of a turbulent channel flow.To separate different sources of the error,we conduct both direct numerical simulations(DNS)and LES,and apply ...We analyze the error of large-eddy simulation(LES)in wall pressure fluctuation of a turbulent channel flow.To separate different sources of the error,we conduct both direct numerical simulations(DNS)and LES,and apply an explicit filter on DNS data to obtain filtered DNS(FDNS)data.The error of LES is consequently decomposed into two parts:The first part is the error of FDNS with respect to DNS,which quantifies the influence of the filter operation.The second part is the difference between LES and FDNS induced by the error of LES in velocity field.By comparing the root-mean-square value and the wavenumber-frequency spectrum of the wall pressure fluctuation,it is found that the inaccuracy of the velocity fluctuations is the dominant source that induces the error of LES in the wall pressure fluctuation.The present study provides a basis on future LES studies of the wall pressure fluctuation.展开更多
Distal gastric cancer(DGC)is a subgroup of gastric cancer(GC),which has different molecular characteristics from proximal gastric cancer(PGC).These differences result in different overall survival(OS)rates;however,dat...Distal gastric cancer(DGC)is a subgroup of gastric cancer(GC),which has different molecular characteristics from proximal gastric cancer(PGC).These differences result in different overall survival(OS)rates;however,data pertaining to the survival rate in PGC or DGC are contradictory.This suggests that the location of GC is not the unique cause of the different survival rates,while the molecular characteristics might be more important factors determining the prognosis of DGC.Therefore,the aim of this study was to discover key prognostic factors in DGC using bioinformatic methods and to explore the potential molecular mechanism.The Cancer Genome Atlas(TCGA)public database was employed to screen data relating to DGC,and we conducted a weighted gene co-expression network analysis(WGCNA)on DGC patient samples to establish co-expression modules.High-weight genes(hub genes)in a dominant color module were identified.In vitro experiments and gene set enrichment analyses(GSEA)were carried out to elucidate the potential molecular mechanism.In this study,139 DGC samples were enrolled to perform a co-expression analysis.According to the correlation between gene modules and clinical characteristics,the royal blue module related to stage M of DGC was screened,and a survival analysis was conducted to show that highcoagulation-factor V(F5)expression was related to the short OS of patients with GC.In vitro experiments confirmed that F5 could promote the migration of GC cells.GSEA suggested that F5 might have affected the prognosis of GC by modulating the activities of the Wnt and/or the TGF-βsignaling pathways.Our results indicated that high F5 expression predicts poor prognosis of patients with DGC,and it functions probably by promoting cell migration through the Wnt and/or the TGF-βsignaling pathways.展开更多
Objective: To assess the effectiveness and safety of manipulation intervention for degenerative lumbar spondylolisthesis(DLS).Methods: This is a systematic review and meta-analysis. A full-scale retrieval method was p...Objective: To assess the effectiveness and safety of manipulation intervention for degenerative lumbar spondylolisthesis(DLS).Methods: This is a systematic review and meta-analysis. A full-scale retrieval method was performed until February 1, 2021, including nine databases. The homogeneity of different studies was summarized using the Review Manager. The quality of studies was determined with the Cochrane risk-of-bias tool.The evidence quality was graded with the Grading of Recommendations, Assessment, Development, and Evaluations approach.Results: A total of 6 studies involving 524 participants were included. The review demonstrated that manipulation has statistically significant improvements for treating DLS according to Japanese Orthopedic Association scores(mean difference, 3.76;95% confidence interval, 2.63 to 4.90;P <.001) and visual analog scale scores(mean difference,-1.50;95% confidence interval,-1.66 to-1.33;P <.001)compared to the control group. One study reported that the difference in the Oswestry Disability Index between the traction group and the combination of manipulation and traction group was statistically significant(P <.05), while another reported that manipulation treatment can significantly improve the lumbar spine rotation angle on X-ray images compared with the baseline data(P <.05). Moreover, the manipulation group(experimental group) had fewer adverse events than the lumbar traction group(control group).Conclusion: Manipulation intervention is more effective and safer for DLS. Nevertheless, large-scale randomized controlled trials are required to confirm the current conclusions.展开更多
The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients wit...The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients with different Lauren subtypes is of great clinical value.We performed a univariate Cox regression to identify those genes with prognostic value of overall survival(OS)and peritoneal-specified disease-free survival(psDFS)from the Gene Expression Omnibus database.The candidate genes were screened by the Subpopulation Treatment Effect Pattern Plot(STEPP)method.Propensity score matching(PSM)analysis was used to reduce the interference of confounders on the results.Based on the optimal cut-off values determined by the STEPP method,we found overexpression of three genes(HAND2-AS1,PRKAA2,and VLDLR)was correlated with shorter 1-year psDFS among patients with diffuse-type than that of patients with intestinal-type GC,and it is highly significant.Gene Set Enrichment Analysis(GSEA)potentially suggested that the three genes promote the early occurrence of peritoneal metastasis in patients with diffuse-type GC through glucose metabolism-related pathways.These three genes may be potential biomarkers.They can be used to assess the risk of peritoneal metastases to guide treatment decisions and follow-up strategies.展开更多
Breast cancer is the most common cancer and the leading cause of cancer death in women worldwide.1 Tumor-infiltrating myeloid cells(TiMs),key components of tumor microenvironment,are considered to be potential therape...Breast cancer is the most common cancer and the leading cause of cancer death in women worldwide.1 Tumor-infiltrating myeloid cells(TiMs),key components of tumor microenvironment,are considered to be potential therapeutic targets for cancer recently,2.3 however,their heterogeneity remains insufficiently characterized in different breast cancer subtypes.A more detailed TIM transcriptional atlas across breast cancer subtypes at the single-cell level is required to better understand the underlying mechanisms influencing the prognosis of breast cancer patients.展开更多
Immunogenic death is a form of programmed cell death that is common in the development and progression of cancer.However,its impact on tumor progression differs depending on the location of the tumor.Meanwhile,it also...Immunogenic death is a form of programmed cell death that is common in the development and progression of cancer.However,its impact on tumor progression differs depending on the location of the tumor.Meanwhile,it also plays an important role in antitumor immunity because the process of immunogenic death can release substances that activate immunity.1 Therefore,in this study,the key mechanism of mediating immunogenic death in hepatocellular carcinoma(HCC)was found from the excavation of the immunogenic death characteristics of pan-cancer and the in-depth investigation of its effects on different tumor types(Fig.1A).展开更多
Cement Stabilized Loess(CSL)sample has a long history as a method of improving building foundations.In this paper,the main physical(specific gravity,consistency limit,optimum moisture content,and maximum dry den-sity)...Cement Stabilized Loess(CSL)sample has a long history as a method of improving building foundations.In this paper,the main physical(specific gravity,consistency limit,optimum moisture content,and maximum dry den-sity)and mechanical properties(Unconfined Compressive Strength(UCS)and shear strength par ameters)of CSL samples with different cement content were inves tigated,and the change reasons were exp lored by mean of SEM test.Meanwhile,quantitative analysis sofware Image Pro Plus(IPP)6.0 was used to characterize the microstruc-tural evolution of pores in compacted loess and CSL sample.As the cement content increased,the specific gravity and optimum water content in the CSL samples increased and the liquid limit and maximum dry density decreased.The plastic limit exhibits an increase followed by a decrease,with the plasticity index changing in the opposite tendency.The UCS and shear strengths of the CSL samples increased with increa sing cement con-tent,and the USC and cement content was better ftted using the Asymptotic model under the same curing time.The growth rate of the UCS and shear strength parameters were significantly reduced at cement contents above 2%.The results of Scanning Hlectron Microscopy(SEM)showed that the structure of the CSL samples was denser and had no obvious inter-aggregate pores.Meanwhile,compared to compacted loess,produced C-S-H gel and ettringite.Quantitative analysis of compacted loess and CSL sample by IPP software.Compared to compacted loess,the average pore diameter and average pore area of the CSL sample decreased from 12.44μm and 229.04 μm^(2) to 8.72 μm and 84.68μm^(2),a reduction of 29.9% and 63.0%,respectively.The pore shape tends to fatten,but there is basically no efet on the pore angle distrbution.Fnally,a systematic description of the phy-sicochemical reactions occurring during the formation of the CSL sample structure was made,and a schematic diagram of the formation of the CSL sample structure was created.展开更多
Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function a...Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function after surgery,with spinal cord ischemia–reperfusion injury(SCII)identified as the primary cause.Spinal cord compression results in local ischemia and blood perfusion following decompression is fundamental to SCII.However,owing to inadequate perioperative blood flow monitoring,direct evidence regarding the occurrence of SCII after decompression is lacking.The objective of this study was to establish a suitable animal model for investigating the underlying mechanism of spinal cord ischemia–reperfusion injury following decom-pression surgery for degenerative cervical myelopathy(DCM)and to elucidate alterations in neurological function and local blood flow within the spinal cord before and after decompression.Methods:Twenty-four Sprague–Dawley rats were allocated to three groups:the DCM group(cervical compression group,with implanted compression material in the spinal canal,n=8),the DCM-D group(cervical decompression group,with removal of compression material from the spinal canal 4 weeks after implantation,n=8),and the SHAM group(sham operation,n=8).Von Frey test,forepaw grip strength,and gait were assessed within 4 weeks post-implantation.Spinal cord compression was evaluated using magnetic resonance imaging.Local blood flow in the spinal cord was monitored during the perioperative decompression.The rats were sacrificed 1 week after decompression to observe morphological changes in the compressed or decompressed segments of the spinal cord.Additionally,NeuN expression and the oxidative damage marker 8-oxoG DNA were analyzed.Results:Following spinal cord compression,abnormal mechanical pain worsened,and a decrease in forepaw grip strength was observed within 1–4 weeks.Upon decompression,the abnormal mechanical pain subsided,and forepaw grip strength was restored;however,neither reached the level of the sham operation group.Decompression leads to an increase in the local blood flow,indicating improved perfusion of the spinal cord.The number of NeuN-positive cells in the spinal cord of rats in the DCM-D group exceeded that in the DCM group but remained lower than that in the SHAM group.Notably,a higher level of 8-oxoG DNA expression was observed,suggesting oxidative stress following spinal cord decompression.Conclusion:This model is deemed suitable for analyzing the underlying mechanism of SCII following decompressive cervical laminectomy,as we posit that the obtained results are comparable to the clinical progression of degenerative cervical myelopathy(DCM)post-decompression and exhibit analogous neurological alterations.Notably,this model revealed ischemic reperfusion in the spinal cord after decompression,concomitant with oxidative damage,which plausibly underlies the neurological deterioration observed after decompression.展开更多
Realistic urban scene generation has been extensively studied for the sake of the development of autonomous vehicles. However, the research has primarily focused on the synthesis of vehicles and pedestrians, while the...Realistic urban scene generation has been extensively studied for the sake of the development of autonomous vehicles. However, the research has primarily focused on the synthesis of vehicles and pedestrians, while the generation of cyclists is rarely presented due to its complexity. This paper proposes a perspective-aware and realistic cyclist generation method via object retrieval. Images, semantic maps, and depth labels of objects are first collected from existing datasets, categorized by class and perspective, and calculated by an algorithm newly designed according to imaging principles. During scene generation, objects with the desired class and perspective are retrieved from the collection and inserted into the background, which is then sent to the modified 2D synthesis model to generate images. This pipeline introduces a perspective computing method, utilizes object retrieval to control the perspective accurately, and modifies a diffusion model to achieve high fidelity. Experiments show that our proposal gets a 2.36 Fréchet Inception Distance, which is lower than the competitive methods, indicating a superior realistic expression ability. When these images are used for augmentation in the semantic segmentation task, the performance of ResNet-50 on the target class can be improved by 4.47%. These results demonstrate that the proposed method can be used to generate cyclists in corner cases to augment model training data, further enhancing the perception capability of autonomous vehicles and improving the safety performance of autonomous driving technology.展开更多
Transmissive metasurfaces have provided an efficient platform to manipulate electromagnetic(EM)waves, but previously adopted multilayer meta-atoms are too thick and/or the design approach fully relies on brute-force s...Transmissive metasurfaces have provided an efficient platform to manipulate electromagnetic(EM)waves, but previously adopted multilayer meta-atoms are too thick and/or the design approach fully relies on brute-force simulations without physical understandings. Here, based on coupled-mode theory(CMT) analyses on multilayer meta-atoms of distinct types, it is found that meta-atoms of a specific type only allows the phase coverage over a particular range, thus suitable for polarization-control applications.However, combinations of meta-atoms with distinct types are necessary for building ultra-thin wavefront-control meta-devices requiring 360° phase coverage. Based on these physical understandings,high-efficiency meta-atoms are designed/fabricated, and used to construct three typical meta-devices,including quarter-and half-wave plates and a beam deflector. Our results elucidate the physics underlying the interplay between thicknesses and performances of transmissive metasurfaces, which can guide the realizations of miniaturized transmissive meta-devices in different frequency domains.展开更多
As a carbon-rich material produced by pyrolysis of biomass,biochar features low cost,large specific surface area,and widely available feedstocks based on the functional diversity and environmental-friendly properties,...As a carbon-rich material produced by pyrolysis of biomass,biochar features low cost,large specific surface area,and widely available feedstocks based on the functional diversity and environmental-friendly properties,it has received increasing attention in the fields of pollutant removal due to three win-win effects of water remediation,carbon sequestration and reutilization of wastes.To design excellent biochar-based catalysts for environmental applications,one must understand recent advances in the catalysts for contaminant removal.This review focuses on the current application of biochar-based catalysts in redox systems,Fenton-like systems,sonocatalytic systems and photocatalytic systems.Besides in-depth discussion in effects of preparation conditions on physicochemical characteristics of biochars,the review supplements new preparation technologies of biochar and biochar-based catalysts.Most importantly,the advantages/shortcomings,catalysis mechanisms,as well as the pollutant removal ability of different types of biochar-based catalysts are discussed.The environmental risks of the catalyst applications are also elaborated on.Future research on biochar-based catalyst production and its environmental applications is discussed.The review provides a good overview of the current advances of biochar-based catalysts in pollutant control and the future research directions.展开更多
基金the Science and Technology Programs of Gansu Province(Grant Nos.21JR1RA248,23YFGA0050)the Young Scholars Science Foundation of Lanzhou Jiaotong University(Grant Nos.2020039,2020017)+2 种基金the Special Funds for Guiding Local Scientific and Technological Development by the Central Government(Grant No.22ZY1QA005)the National Natural Science Foundation of China(Grant No.72361019)the Gansu Provincial Outstanding Graduate Students Innovation Star Program(Grant No.2023CXZX-574).
文摘Given the difficulty in accurately evaluating the fatigue performance of large composite wind turbine blades(referred to as blades),this paper takes the main beam structure of the blade with a rectangular cross-sectionas the simulation object and establishes a composite laminate rectangular beam structure that simultaneouslyincludes the flange,web,and adhesive layer,referred to as the blade main beam sub-structure specimen,throughthe definition of blade sub-structures.This paper examines the progressive damage evolution law of the compositelaminate rectangular beam utilizing an improved 3D Hashin failure criterion,cohesive zone model,B-K failurecriterion,and computer simulation technology.Under static loading,the layup angle of the anti-shear web hasa close relationship with the static load-carrying capacity of the composite laminate rectangular beam;under fatigueloading,the fatigue damage will first occur in the lower flange adhesive area of the whole composite laminaterectangular beam and ultimately result in the fracture failure of the entire structure.These results provide a theoreticalreference and foundation for evaluating and predicting the fatigue performance of the blade main beamstructure and even the full-size blade.
文摘The millimeter-Wave(mmWave)communication with the advantages of abundant bandwidth and immunity to interference has been deemed a promising technology to greatly improve network capacity.However,due to such characteristics of mmWave,as short transmission distance,high sensitivity to the blockage,and large propagation path loss,handover issues(including trigger condition and target beam selection)become much complicated.In this paper,we design a novel handover scheme to optimize the overall system throughput as well as the total system delay while guaranteeing the Quality of Service(QoS)of each User Equipment(UE).Specifically,the proposed handover scheme called O-MAPPO integrates the Reinforcement Learning(RL)algorithm and optimization theory.The RL algorithm known as Multi-Agent Proximal Policy Optimization(MAPPO)plays a role in determining handover trigger conditions.Further,we propose an optimization problem in conjunction with MAPPO to select the target base station.The aim is to evaluate and optimize the system performance of total throughput and delay while guaranteeing the QoS of each UE after the handover decision is made.The numerical results show the overall system throughput and delay with our method are slightly worse than that with the exhaustive search method but much better than that using another typical RL algorithm Deep Deterministic Policy Gradient(DDPG).
文摘With the continuous integration of new energy into the power grid,various new attacks continue to emerge and the feature distributions are constantly changing during the deployment of intelligent pumped storage power stations.The intrusion detection model trained on the old data is hard to effectively identify new attacks,and it is difficult to update the intrusion detection model in time when lacking data.To solve this issue,by using model-based transfer learning methods,in this paper we propose a convolutional neural network(CNN)based transfer online sequential extreme learning machine(TOS-ELM)scheme to enable the online intrusion detection,which is called CNN-TOSELM in this paper.In our proposed scheme,we use pre-trained CNN to extract the characteristics of the target domain data as input,and then build online learning classifier TOS-ELM to transfer the parameter of the ELM classifier of the source domain.Experimental results show the proposed CNNTOSELM scheme can achieve better detection performance and extremely short model update time for intelligent pumped storage power stations.
基金This research is supported by the National Natural Science Foundation of China(NFSC)Basic Science Center Program for“Multiscale Problems in Nonlinear Mechanics”(Grant 11988102)the National Key Project(Grant GJXM92579)Shizhao Wang acknowledges the support from the National Natural Science Foundation of China(Grant 11922214).
文摘We analyze the error of large-eddy simulation(LES)in wall pressure fluctuation of a turbulent channel flow.To separate different sources of the error,we conduct both direct numerical simulations(DNS)and LES,and apply an explicit filter on DNS data to obtain filtered DNS(FDNS)data.The error of LES is consequently decomposed into two parts:The first part is the error of FDNS with respect to DNS,which quantifies the influence of the filter operation.The second part is the difference between LES and FDNS induced by the error of LES in velocity field.By comparing the root-mean-square value and the wavenumber-frequency spectrum of the wall pressure fluctuation,it is found that the inaccuracy of the velocity fluctuations is the dominant source that induces the error of LES in the wall pressure fluctuation.The present study provides a basis on future LES studies of the wall pressure fluctuation.
基金funds,including the National Natural Science Foundation of China(Nos.81972331,81972751,81572374)The National Key Research and Development Program of China(2017YFC1308900)+2 种基金Technological Special Project of Liaoning Province of China(2019020176-JH1/103)Science and Technology Plan Project of Liaoning Province(NO.2013225585)The General Projects of Liaoning Province Colleges and Universities(LFWK201706).
文摘Distal gastric cancer(DGC)is a subgroup of gastric cancer(GC),which has different molecular characteristics from proximal gastric cancer(PGC).These differences result in different overall survival(OS)rates;however,data pertaining to the survival rate in PGC or DGC are contradictory.This suggests that the location of GC is not the unique cause of the different survival rates,while the molecular characteristics might be more important factors determining the prognosis of DGC.Therefore,the aim of this study was to discover key prognostic factors in DGC using bioinformatic methods and to explore the potential molecular mechanism.The Cancer Genome Atlas(TCGA)public database was employed to screen data relating to DGC,and we conducted a weighted gene co-expression network analysis(WGCNA)on DGC patient samples to establish co-expression modules.High-weight genes(hub genes)in a dominant color module were identified.In vitro experiments and gene set enrichment analyses(GSEA)were carried out to elucidate the potential molecular mechanism.In this study,139 DGC samples were enrolled to perform a co-expression analysis.According to the correlation between gene modules and clinical characteristics,the royal blue module related to stage M of DGC was screened,and a survival analysis was conducted to show that highcoagulation-factor V(F5)expression was related to the short OS of patients with GC.In vitro experiments confirmed that F5 could promote the migration of GC cells.GSEA suggested that F5 might have affected the prognosis of GC by modulating the activities of the Wnt and/or the TGF-βsignaling pathways.Our results indicated that high F5 expression predicts poor prognosis of patients with DGC,and it functions probably by promoting cell migration through the Wnt and/or the TGF-βsignaling pathways.
基金supported by grants from the Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine (ZYYCXTD-C-202003)the China Academy of Chinese Medical Sciences Evidence-based Capacity Improvement Project (ZZ13-024-7)
文摘Objective: To assess the effectiveness and safety of manipulation intervention for degenerative lumbar spondylolisthesis(DLS).Methods: This is a systematic review and meta-analysis. A full-scale retrieval method was performed until February 1, 2021, including nine databases. The homogeneity of different studies was summarized using the Review Manager. The quality of studies was determined with the Cochrane risk-of-bias tool.The evidence quality was graded with the Grading of Recommendations, Assessment, Development, and Evaluations approach.Results: A total of 6 studies involving 524 participants were included. The review demonstrated that manipulation has statistically significant improvements for treating DLS according to Japanese Orthopedic Association scores(mean difference, 3.76;95% confidence interval, 2.63 to 4.90;P <.001) and visual analog scale scores(mean difference,-1.50;95% confidence interval,-1.66 to-1.33;P <.001)compared to the control group. One study reported that the difference in the Oswestry Disability Index between the traction group and the combination of manipulation and traction group was statistically significant(P <.05), while another reported that manipulation treatment can significantly improve the lumbar spine rotation angle on X-ray images compared with the baseline data(P <.05). Moreover, the manipulation group(experimental group) had fewer adverse events than the lumbar traction group(control group).Conclusion: Manipulation intervention is more effective and safer for DLS. Nevertheless, large-scale randomized controlled trials are required to confirm the current conclusions.
基金This research was approved by National Natural Science Foundation of China(No.81972331)National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2017ZX09304025).
文摘The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients with different Lauren subtypes is of great clinical value.We performed a univariate Cox regression to identify those genes with prognostic value of overall survival(OS)and peritoneal-specified disease-free survival(psDFS)from the Gene Expression Omnibus database.The candidate genes were screened by the Subpopulation Treatment Effect Pattern Plot(STEPP)method.Propensity score matching(PSM)analysis was used to reduce the interference of confounders on the results.Based on the optimal cut-off values determined by the STEPP method,we found overexpression of three genes(HAND2-AS1,PRKAA2,and VLDLR)was correlated with shorter 1-year psDFS among patients with diffuse-type than that of patients with intestinal-type GC,and it is highly significant.Gene Set Enrichment Analysis(GSEA)potentially suggested that the three genes promote the early occurrence of peritoneal metastasis in patients with diffuse-type GC through glucose metabolism-related pathways.These three genes may be potential biomarkers.They can be used to assess the risk of peritoneal metastases to guide treatment decisions and follow-up strategies.
基金supported by the National Natural Science Foundation of China (No.81974418)Basic Research Project of Liaoning Province (No.JC2019002)+1 种基金Doctoral Start-up Foundation of Liaoning Province (No.2019-BS-284)Youth backbone Support Program of China Medical University (No.QGZ2018081).
文摘Breast cancer is the most common cancer and the leading cause of cancer death in women worldwide.1 Tumor-infiltrating myeloid cells(TiMs),key components of tumor microenvironment,are considered to be potential therapeutic targets for cancer recently,2.3 however,their heterogeneity remains insufficiently characterized in different breast cancer subtypes.A more detailed TIM transcriptional atlas across breast cancer subtypes at the single-cell level is required to better understand the underlying mechanisms influencing the prognosis of breast cancer patients.
文摘Immunogenic death is a form of programmed cell death that is common in the development and progression of cancer.However,its impact on tumor progression differs depending on the location of the tumor.Meanwhile,it also plays an important role in antitumor immunity because the process of immunogenic death can release substances that activate immunity.1 Therefore,in this study,the key mechanism of mediating immunogenic death in hepatocellular carcinoma(HCC)was found from the excavation of the immunogenic death characteristics of pan-cancer and the in-depth investigation of its effects on different tumor types(Fig.1A).
基金This study was supported by the key research and development program of Shaanxi Province in the form of grants awarded to KL(Grant No.2017ZDXM-SF-087)BWY(Grant No.2020SF-436).
文摘Cement Stabilized Loess(CSL)sample has a long history as a method of improving building foundations.In this paper,the main physical(specific gravity,consistency limit,optimum moisture content,and maximum dry den-sity)and mechanical properties(Unconfined Compressive Strength(UCS)and shear strength par ameters)of CSL samples with different cement content were inves tigated,and the change reasons were exp lored by mean of SEM test.Meanwhile,quantitative analysis sofware Image Pro Plus(IPP)6.0 was used to characterize the microstruc-tural evolution of pores in compacted loess and CSL sample.As the cement content increased,the specific gravity and optimum water content in the CSL samples increased and the liquid limit and maximum dry density decreased.The plastic limit exhibits an increase followed by a decrease,with the plasticity index changing in the opposite tendency.The UCS and shear strengths of the CSL samples increased with increa sing cement con-tent,and the USC and cement content was better ftted using the Asymptotic model under the same curing time.The growth rate of the UCS and shear strength parameters were significantly reduced at cement contents above 2%.The results of Scanning Hlectron Microscopy(SEM)showed that the structure of the CSL samples was denser and had no obvious inter-aggregate pores.Meanwhile,compared to compacted loess,produced C-S-H gel and ettringite.Quantitative analysis of compacted loess and CSL sample by IPP software.Compared to compacted loess,the average pore diameter and average pore area of the CSL sample decreased from 12.44μm and 229.04 μm^(2) to 8.72 μm and 84.68μm^(2),a reduction of 29.9% and 63.0%,respectively.The pore shape tends to fatten,but there is basically no efet on the pore angle distrbution.Fnally,a systematic description of the phy-sicochemical reactions occurring during the formation of the CSL sample structure was made,and a schematic diagram of the formation of the CSL sample structure was created.
基金Wangjing Hospital Affiliated to China Academy of Chinese Medical Sciences,Grant/Award Number:WJYY-YJKT-2022-13。
文摘Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function after surgery,with spinal cord ischemia–reperfusion injury(SCII)identified as the primary cause.Spinal cord compression results in local ischemia and blood perfusion following decompression is fundamental to SCII.However,owing to inadequate perioperative blood flow monitoring,direct evidence regarding the occurrence of SCII after decompression is lacking.The objective of this study was to establish a suitable animal model for investigating the underlying mechanism of spinal cord ischemia–reperfusion injury following decom-pression surgery for degenerative cervical myelopathy(DCM)and to elucidate alterations in neurological function and local blood flow within the spinal cord before and after decompression.Methods:Twenty-four Sprague–Dawley rats were allocated to three groups:the DCM group(cervical compression group,with implanted compression material in the spinal canal,n=8),the DCM-D group(cervical decompression group,with removal of compression material from the spinal canal 4 weeks after implantation,n=8),and the SHAM group(sham operation,n=8).Von Frey test,forepaw grip strength,and gait were assessed within 4 weeks post-implantation.Spinal cord compression was evaluated using magnetic resonance imaging.Local blood flow in the spinal cord was monitored during the perioperative decompression.The rats were sacrificed 1 week after decompression to observe morphological changes in the compressed or decompressed segments of the spinal cord.Additionally,NeuN expression and the oxidative damage marker 8-oxoG DNA were analyzed.Results:Following spinal cord compression,abnormal mechanical pain worsened,and a decrease in forepaw grip strength was observed within 1–4 weeks.Upon decompression,the abnormal mechanical pain subsided,and forepaw grip strength was restored;however,neither reached the level of the sham operation group.Decompression leads to an increase in the local blood flow,indicating improved perfusion of the spinal cord.The number of NeuN-positive cells in the spinal cord of rats in the DCM-D group exceeded that in the DCM group but remained lower than that in the SHAM group.Notably,a higher level of 8-oxoG DNA expression was observed,suggesting oxidative stress following spinal cord decompression.Conclusion:This model is deemed suitable for analyzing the underlying mechanism of SCII following decompressive cervical laminectomy,as we posit that the obtained results are comparable to the clinical progression of degenerative cervical myelopathy(DCM)post-decompression and exhibit analogous neurological alterations.Notably,this model revealed ischemic reperfusion in the spinal cord after decompression,concomitant with oxidative damage,which plausibly underlies the neurological deterioration observed after decompression.
基金supported by the Cultivation Program for Major Scientific Research Projects of Harbin Institute of Technology(ZDXMPY20180109).
文摘Realistic urban scene generation has been extensively studied for the sake of the development of autonomous vehicles. However, the research has primarily focused on the synthesis of vehicles and pedestrians, while the generation of cyclists is rarely presented due to its complexity. This paper proposes a perspective-aware and realistic cyclist generation method via object retrieval. Images, semantic maps, and depth labels of objects are first collected from existing datasets, categorized by class and perspective, and calculated by an algorithm newly designed according to imaging principles. During scene generation, objects with the desired class and perspective are retrieved from the collection and inserted into the background, which is then sent to the modified 2D synthesis model to generate images. This pipeline introduces a perspective computing method, utilizes object retrieval to control the perspective accurately, and modifies a diffusion model to achieve high fidelity. Experiments show that our proposal gets a 2.36 Fréchet Inception Distance, which is lower than the competitive methods, indicating a superior realistic expression ability. When these images are used for augmentation in the semantic segmentation task, the performance of ResNet-50 on the target class can be improved by 4.47%. These results demonstrate that the proposed method can be used to generate cyclists in corner cases to augment model training data, further enhancing the perception capability of autonomous vehicles and improving the safety performance of autonomous driving technology.
基金supported by National Key Research and Development Program of China(2017YFA0303500)the National Natural Science Foundation of China(11704240,11734007,and11674068)+3 种基金Natural Science Foundation of Shanghai(17ZR1409500 and 18QA1401800)Shanghai Science and Technology Committee(16JC1403100)Shanghai East Scholar PlanHehai University-CIOMP Joint Fund
文摘Transmissive metasurfaces have provided an efficient platform to manipulate electromagnetic(EM)waves, but previously adopted multilayer meta-atoms are too thick and/or the design approach fully relies on brute-force simulations without physical understandings. Here, based on coupled-mode theory(CMT) analyses on multilayer meta-atoms of distinct types, it is found that meta-atoms of a specific type only allows the phase coverage over a particular range, thus suitable for polarization-control applications.However, combinations of meta-atoms with distinct types are necessary for building ultra-thin wavefront-control meta-devices requiring 360° phase coverage. Based on these physical understandings,high-efficiency meta-atoms are designed/fabricated, and used to construct three typical meta-devices,including quarter-and half-wave plates and a beam deflector. Our results elucidate the physics underlying the interplay between thicknesses and performances of transmissive metasurfaces, which can guide the realizations of miniaturized transmissive meta-devices in different frequency domains.
基金the National Natural Science Foundation of China under Grant 41671331,the Innovative Approaches Special Project of the Ministry of Science and Technology of China under Grant(2020IM020300)the Beijing-Tianjin-Hebei Collaborative Innovation Promotion Project,China(Z201100006720001)the National Key Research and Development Program of China under Grant 2016YFA0600103.
文摘As a carbon-rich material produced by pyrolysis of biomass,biochar features low cost,large specific surface area,and widely available feedstocks based on the functional diversity and environmental-friendly properties,it has received increasing attention in the fields of pollutant removal due to three win-win effects of water remediation,carbon sequestration and reutilization of wastes.To design excellent biochar-based catalysts for environmental applications,one must understand recent advances in the catalysts for contaminant removal.This review focuses on the current application of biochar-based catalysts in redox systems,Fenton-like systems,sonocatalytic systems and photocatalytic systems.Besides in-depth discussion in effects of preparation conditions on physicochemical characteristics of biochars,the review supplements new preparation technologies of biochar and biochar-based catalysts.Most importantly,the advantages/shortcomings,catalysis mechanisms,as well as the pollutant removal ability of different types of biochar-based catalysts are discussed.The environmental risks of the catalyst applications are also elaborated on.Future research on biochar-based catalyst production and its environmental applications is discussed.The review provides a good overview of the current advances of biochar-based catalysts in pollutant control and the future research directions.
