在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异...在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异常值检测能力。本研究采用遥感海浪有效波高数据,构建双向长短期记忆网络(bi-directional long short term memory,Bi-LSTM)模型对有效波高进行预测,结合阈值方法进行异常检测,与3σ准则法、孤立森林模型法、 LSTM模型法以及VAE-LSTM模型法进行异常检测精度比较,探究基于Bi-LSTM的质量控制模型在遥感海浪数据异常值检测方面的能力。试验结果表明,Bi-LSTM质量控制模型具有良好的异常值检测效果,其精准率、召回率、 F1分数和运行时间分别为91%、 93%、 92和3.35 s,综合评价效果最佳,可有效对遥感海浪数据进行质量控制。展开更多
Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult t...Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult to compare their research results.Methods:The time for wound closure was evaluated and recorded through gross observation.The regression equation between the healing time and the diameter of skin defect was established,which can be used to predict the healing time for a certain skin defect size in rats.Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages,and the functional skin repair was quantitatively scored.Results:The critical-size defect of rats was determined based on the maximum capacity of structural skin repair,and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages.The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter.The concept of structural repair and the category of functional repair of injured skin are put forward.The regression equation between the structural skin healing time and defect diameters is established.Conclusion:The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter.The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats.展开更多
In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadeq...In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.展开更多
The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling...The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling and structural analysis were performed for the repair reinforcement of a steel pipeline with a composite bandage.A preliminary analysis of possible contact interaction schemes was implemented based on the theory of cylindrical shells,taking into account transverse shear deformations.The finite element method was used for a detailed study of the stress state of the composite bandage and the reinforced section of the pipeline.The limit state of the reinforced section was assessed based on the von Mises criterion for steel and the Tsai-Wu criterion for composites.The effectiveness of the repair was demonstrated on a pipeline whose wall thickness had decreased by 20%as a result of corrosion damage.At a nominal pressure of P=6 MPa,the maximum normal stress in the weakened area reached 381 MPa.The installation of a composite bandage reduced this stress to 312 MPa,making the repaired section virtually as strong as the undamaged pipeline.Due to the linearity of the problem,the results obtained can be easily used to find critical internal pressure values.展开更多
The central nervous system(CNS)does not function in isolation-it engages in continuous molecular dialogue with the vascular and immune systems.Traditionally,the blood-brain barrier(BBB)was portrayed solely as an imper...The central nervous system(CNS)does not function in isolation-it engages in continuous molecular dialogue with the vascular and immune systems.Traditionally,the blood-brain barrier(BBB)was portrayed solely as an impermeable wall,safeguarding the CNS by excluding blood-derived molecules and circulating cells.However,this view has evolved.The BBB is now recognized as a dynamic interface that selectively regulates the exchange of signals,cells.展开更多
Fissured rocks are prevalent in geotechnical engineering and can significantlyimpact the stability of engineering structures.Microbial-induced carbonate precipitation(MICP)technology provides an ecofriendly solution f...Fissured rocks are prevalent in geotechnical engineering and can significantlyimpact the stability of engineering structures.Microbial-induced carbonate precipitation(MICP)technology provides an ecofriendly solution for repairing fissuredrocks.To optimize repair effectiveness,this study firstinvestigated the effects of environmental factors on bacterial growth,urease activity,and calcium carbonate yield.The optimal MICP scheme was determined to be a pH of 9,a temperature of 25℃,and a cementation solution concentration of 0.5 mol/L.Subsequently,the sandstone specimens with various fissureapertures were repaired using MICP with different bacterial concentrations.Dynamic tests were carried out on the repaired specimens using a split Hopkinson pressure bar system.The experimental results indicate that the dynamic strength of the MICP-repaired specimens positively correlates with strain rate,but decreases with increasing bacterial concentration and fissureaperture.These factors have little effect on the progressive failure behavior.Surface cracks were mainly compression-shear cracks in the repair area and tensile-shear cracks at the end of the specimen.Moreover,the crystal morphology observed by scanning electron microscope indicates that MICP primarily produces vaterite crystals,and lower bacterial concentrations favor the formation of more stable calcite crystals,thereby enhancing the cementitious properties.Furthermore,X-ray computed tomography demonstrates an uneven distribution of calcium carbonate within fissures,with higher fillingrates observed at the injection end and at the bottom of the fissures.Lower bacterial concentrations and smaller fissureapertures are conducive to more uniform distribution and increased fillingrate of calcium carbonate,with fissureaperture exerting a more dominant influence.展开更多
Automated Program Repair(APR)techniques have shown significant potential in mitigating the cost and complexity associated with debugging by automatically generating corrective patches for software defects.Despite cons...Automated Program Repair(APR)techniques have shown significant potential in mitigating the cost and complexity associated with debugging by automatically generating corrective patches for software defects.Despite considerable progress in APR methodologies,existing approaches frequently lack contextual awareness of runtime behaviors and structural intricacies inherent in buggy source code.In this paper,we propose a novel APR approach that integrates attention mechanisms within an autoencoder-based framework,explicitly utilizing structural code affinity and execution context correlation derived from stack trace analysis.Our approach begins with an innovative preprocessing pipeline,where code segments and stack traces are transformed into tokenized representations.Subsequently,the BM25 ranking algorithm is employed to quantitatively measure structural code affinity and execution context correlation,identifying syntactically and semantically analogous buggy code snippets and relevant runtime error contexts from extensive repositories.These extracted features are then encoded via an attention-enhanced autoencoder model,specifically designed to capture significant patterns and correlations essential for effective patch generation.To assess the efficacy and generalizability of our proposed method,we conducted rigorous experimental comparisons against DeepFix,a state-of-the-art APR system,using a substantial dataset comprising 53,478 studentdeveloped C programs.Experimental outcomes indicate that our model achieves a notable bug repair success rate of approximately 62.36%,representing a statistically significant performance improvement of over 6%compared to the baseline.Furthermore,a thorough K-fold cross-validation reinforced the consistency,robustness,and reliability of our method across diverse subsets of the dataset.Our findings present the critical advantage of integrating attentionbased learning with code structural and execution context features in APR tasks,leading to improved accuracy and practical applicability.Future work aims to extend the model’s applicability across different programming languages,systematically optimize hyperparameters,and explore alternative feature representation methods to further enhance debugging efficiency and effectiveness.展开更多
In erasure-coded storage systems,updating data requires parity maintenance,which often leads to significant I/O amplification due to“write-after-read”operations.Furthermore,scattered parity placement increases disk ...In erasure-coded storage systems,updating data requires parity maintenance,which often leads to significant I/O amplification due to“write-after-read”operations.Furthermore,scattered parity placement increases disk seek overhead during repair,resulting in degraded system performance.To address these challenges,this paper proposes a Cognitive Update and Repair Method(CURM)that leverages machine learning to classify files into writeonly,read-only,and read-write categories,enabling tailored update and repair strategies.For write-only and read-write files,CURM employs a data-differencemechanism combined with fine-grained I/O scheduling to minimize redundant read operations and mitigate I/O amplification.For read-write files,CURM further reserves adjacent disk space near parity blocks,supporting parallel reads and reducing disk seek overhead during repair.We implement CURM in a prototype system,Cognitive Update and Repair File System(CURFS),and conduct extensive experiments using realworld Network File System(NFS)and Microsoft Research(MSR)workloads on a 25-node cluster.Experimental results demonstrate that CURMimproves data update throughput by up to 82.52%,reduces recovery time by up to 47.47%,and decreases long-term storage overhead by more than 15% compared to state-of-the-art methods including Full Logging(FL),ParityLogging(PL),ParityLoggingwithReservedspace(PLR),andPARIX.These results validate the effectiveness of CURM in enhancing both update and repair performance,providing a scalable and efficient solution for large-scale erasure-coded storage systems.展开更多
Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people...Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people are diagnosed with SCI annually(Singh et al.,2014),and while this number appears quite low,the effect that an SCI has on the patient’s quality of life is drastic,due to the current difficulties to comprehensively treat this illness.The cost of patient care can also be quite costly,amounting to an estimated$1.69 billion in healthcare costs in the USA alone(Mahabaleshwarkar and Khanna,2014).展开更多
The blood-spinal cord barrier is crucial for preserving homeostasis of the central nervous system.After spinal cord injury,autophagic flux within endothelial cells is disrupted,compromising the integrity of the blood-...The blood-spinal cord barrier is crucial for preserving homeostasis of the central nervous system.After spinal cord injury,autophagic flux within endothelial cells is disrupted,compromising the integrity of the blood-spinal cord barrier.This disruption facilitates extensive infiltration of inflammatory cells,resulting in exacerbated neuroinflammatory responses,neuronal death,and impaired neuronal regeneration.Previous research has demonstrated that photobiomodulation promotes the regeneration of damaged nerves following spinal cord injury by inhibiting the recruitment of inflammatory cells to the injured site and restoring neuronal mitochondrial function.However,the precise mechanisms by which photobiomodulation regulates neuroinflammation remain incompletely elucidated.In this study,we established a mouse model of spinal cord injury and assessed the effects of photobiomodulation treatment.Photobiomodulation effectively cleared damaged mitochondria from endothelial cells in mice,promoting recovery of hindlimb motor function.Using microvascular endothelial bEnd.3 cells subjected to oxygen-glucose deprivation,we found that the effects of photobiomodulation were mediated through activation of the PINK1/Parkin pathway.Additionally,photobiomodulation reduced mitochondrial oxidative stress levels and increased the expression of tight junction proteins within the blood-spinal cord barrier.Our findings suggest that photobiomodulation activates mitochondrial autophagy in endothelial cells through the PINK1/Parkin pathway,thereby promoting repair of the blood-spinal cord barrier following spinal cord injury.展开更多
Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after inju...Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.展开更多
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu...Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.展开更多
短期预测在智能电网建设中扮演着重要角色,深刻影响电网发输变配用各个环节的智能化改造。短期预测一般基于系统实测数据,而传感器故障,数据传输错误等原因会导致数据质量下降,严重影响短期预测的精确性。为建立数据质量受损情况下的精...短期预测在智能电网建设中扮演着重要角色,深刻影响电网发输变配用各个环节的智能化改造。短期预测一般基于系统实测数据,而传感器故障,数据传输错误等原因会导致数据质量下降,严重影响短期预测的精确性。为建立数据质量受损情况下的精确短期预测模型,提出了结合数据预处理和双向长短期记忆(bi-directional long short-term memory,Bi-LSTM)的短期预测框架Bi-LSTM-DP(bi-directional long short-term memory data preprocessing)。在Bi-LSTM-DP中,采集的数据首先通过均值填补缺失值,进而基于Savitzky-Golay滤波器对数据降噪,最后采用Bi-LSTM提取时间序列的信息,实现短期预测。为了评估所提方法的性能,文中使用实测的公开数据集分别预测风电发电量和负荷需求,与其他参考方法对比表明了所述方法的有效性和鲁棒性。展开更多
文摘在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异常值检测能力。本研究采用遥感海浪有效波高数据,构建双向长短期记忆网络(bi-directional long short term memory,Bi-LSTM)模型对有效波高进行预测,结合阈值方法进行异常检测,与3σ准则法、孤立森林模型法、 LSTM模型法以及VAE-LSTM模型法进行异常检测精度比较,探究基于Bi-LSTM的质量控制模型在遥感海浪数据异常值检测方面的能力。试验结果表明,Bi-LSTM质量控制模型具有良好的异常值检测效果,其精准率、召回率、 F1分数和运行时间分别为91%、 93%、 92和3.35 s,综合评价效果最佳,可有效对遥感海浪数据进行质量控制。
基金National Key Research and Development Program of China,Grant/Award Number:2023YFC2410403。
文摘Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult to compare their research results.Methods:The time for wound closure was evaluated and recorded through gross observation.The regression equation between the healing time and the diameter of skin defect was established,which can be used to predict the healing time for a certain skin defect size in rats.Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages,and the functional skin repair was quantitatively scored.Results:The critical-size defect of rats was determined based on the maximum capacity of structural skin repair,and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages.The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter.The concept of structural repair and the category of functional repair of injured skin are put forward.The regression equation between the structural skin healing time and defect diameters is established.Conclusion:The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter.The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats.
基金Funded by the National Natural Science Foundation of China(No.52473077)China Three Gorges Corporation(No.202403190)。
文摘In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.
文摘The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling and structural analysis were performed for the repair reinforcement of a steel pipeline with a composite bandage.A preliminary analysis of possible contact interaction schemes was implemented based on the theory of cylindrical shells,taking into account transverse shear deformations.The finite element method was used for a detailed study of the stress state of the composite bandage and the reinforced section of the pipeline.The limit state of the reinforced section was assessed based on the von Mises criterion for steel and the Tsai-Wu criterion for composites.The effectiveness of the repair was demonstrated on a pipeline whose wall thickness had decreased by 20%as a result of corrosion damage.At a nominal pressure of P=6 MPa,the maximum normal stress in the weakened area reached 381 MPa.The installation of a composite bandage reduced this stress to 312 MPa,making the repaired section virtually as strong as the undamaged pipeline.Due to the linearity of the problem,the results obtained can be easily used to find critical internal pressure values.
基金supported by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under Award Number K02NS110973 and R01NS126498(to MAP).
文摘The central nervous system(CNS)does not function in isolation-it engages in continuous molecular dialogue with the vascular and immune systems.Traditionally,the blood-brain barrier(BBB)was portrayed solely as an impermeable wall,safeguarding the CNS by excluding blood-derived molecules and circulating cells.However,this view has evolved.The BBB is now recognized as a dynamic interface that selectively regulates the exchange of signals,cells.
基金support from the National Key R&D Program of China(Grant No.2023YFC3081500)the National Natural Science Foundation of China(Grant Nos.52225904 and 52039007).
文摘Fissured rocks are prevalent in geotechnical engineering and can significantlyimpact the stability of engineering structures.Microbial-induced carbonate precipitation(MICP)technology provides an ecofriendly solution for repairing fissuredrocks.To optimize repair effectiveness,this study firstinvestigated the effects of environmental factors on bacterial growth,urease activity,and calcium carbonate yield.The optimal MICP scheme was determined to be a pH of 9,a temperature of 25℃,and a cementation solution concentration of 0.5 mol/L.Subsequently,the sandstone specimens with various fissureapertures were repaired using MICP with different bacterial concentrations.Dynamic tests were carried out on the repaired specimens using a split Hopkinson pressure bar system.The experimental results indicate that the dynamic strength of the MICP-repaired specimens positively correlates with strain rate,but decreases with increasing bacterial concentration and fissureaperture.These factors have little effect on the progressive failure behavior.Surface cracks were mainly compression-shear cracks in the repair area and tensile-shear cracks at the end of the specimen.Moreover,the crystal morphology observed by scanning electron microscope indicates that MICP primarily produces vaterite crystals,and lower bacterial concentrations favor the formation of more stable calcite crystals,thereby enhancing the cementitious properties.Furthermore,X-ray computed tomography demonstrates an uneven distribution of calcium carbonate within fissures,with higher fillingrates observed at the injection end and at the bottom of the fissures.Lower bacterial concentrations and smaller fissureapertures are conducive to more uniform distribution and increased fillingrate of calcium carbonate,with fissureaperture exerting a more dominant influence.
文摘Automated Program Repair(APR)techniques have shown significant potential in mitigating the cost and complexity associated with debugging by automatically generating corrective patches for software defects.Despite considerable progress in APR methodologies,existing approaches frequently lack contextual awareness of runtime behaviors and structural intricacies inherent in buggy source code.In this paper,we propose a novel APR approach that integrates attention mechanisms within an autoencoder-based framework,explicitly utilizing structural code affinity and execution context correlation derived from stack trace analysis.Our approach begins with an innovative preprocessing pipeline,where code segments and stack traces are transformed into tokenized representations.Subsequently,the BM25 ranking algorithm is employed to quantitatively measure structural code affinity and execution context correlation,identifying syntactically and semantically analogous buggy code snippets and relevant runtime error contexts from extensive repositories.These extracted features are then encoded via an attention-enhanced autoencoder model,specifically designed to capture significant patterns and correlations essential for effective patch generation.To assess the efficacy and generalizability of our proposed method,we conducted rigorous experimental comparisons against DeepFix,a state-of-the-art APR system,using a substantial dataset comprising 53,478 studentdeveloped C programs.Experimental outcomes indicate that our model achieves a notable bug repair success rate of approximately 62.36%,representing a statistically significant performance improvement of over 6%compared to the baseline.Furthermore,a thorough K-fold cross-validation reinforced the consistency,robustness,and reliability of our method across diverse subsets of the dataset.Our findings present the critical advantage of integrating attentionbased learning with code structural and execution context features in APR tasks,leading to improved accuracy and practical applicability.Future work aims to extend the model’s applicability across different programming languages,systematically optimize hyperparameters,and explore alternative feature representation methods to further enhance debugging efficiency and effectiveness.
基金supported by the National Natural Science Foundation of China(Grant No.62362019)the Natural Science Foundation of Hainan Province(Grant No.624RC482)the Hainan Provincial Higher Education Teaching Reform Research Project(Grant Hnjg2024-27).
文摘In erasure-coded storage systems,updating data requires parity maintenance,which often leads to significant I/O amplification due to“write-after-read”operations.Furthermore,scattered parity placement increases disk seek overhead during repair,resulting in degraded system performance.To address these challenges,this paper proposes a Cognitive Update and Repair Method(CURM)that leverages machine learning to classify files into writeonly,read-only,and read-write categories,enabling tailored update and repair strategies.For write-only and read-write files,CURM employs a data-differencemechanism combined with fine-grained I/O scheduling to minimize redundant read operations and mitigate I/O amplification.For read-write files,CURM further reserves adjacent disk space near parity blocks,supporting parallel reads and reducing disk seek overhead during repair.We implement CURM in a prototype system,Cognitive Update and Repair File System(CURFS),and conduct extensive experiments using realworld Network File System(NFS)and Microsoft Research(MSR)workloads on a 25-node cluster.Experimental results demonstrate that CURMimproves data update throughput by up to 82.52%,reduces recovery time by up to 47.47%,and decreases long-term storage overhead by more than 15% compared to state-of-the-art methods including Full Logging(FL),ParityLogging(PL),ParityLoggingwithReservedspace(PLR),andPARIX.These results validate the effectiveness of CURM in enhancing both update and repair performance,providing a scalable and efficient solution for large-scale erasure-coded storage systems.
基金supported by the Irish Research Council under the Government of Ireland Postdoctoral Fellowship Project ID-GOIPD/2023/1431(to AS).
文摘Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people are diagnosed with SCI annually(Singh et al.,2014),and while this number appears quite low,the effect that an SCI has on the patient’s quality of life is drastic,due to the current difficulties to comprehensively treat this illness.The cost of patient care can also be quite costly,amounting to an estimated$1.69 billion in healthcare costs in the USA alone(Mahabaleshwarkar and Khanna,2014).
基金supported by the National Natural Science Foundation of China,No.82471411(to ZW and TD)the Key Research and DevelopmentProgram of Shaanxi Province,No.2023-ZDLSF-12(to TD).
文摘The blood-spinal cord barrier is crucial for preserving homeostasis of the central nervous system.After spinal cord injury,autophagic flux within endothelial cells is disrupted,compromising the integrity of the blood-spinal cord barrier.This disruption facilitates extensive infiltration of inflammatory cells,resulting in exacerbated neuroinflammatory responses,neuronal death,and impaired neuronal regeneration.Previous research has demonstrated that photobiomodulation promotes the regeneration of damaged nerves following spinal cord injury by inhibiting the recruitment of inflammatory cells to the injured site and restoring neuronal mitochondrial function.However,the precise mechanisms by which photobiomodulation regulates neuroinflammation remain incompletely elucidated.In this study,we established a mouse model of spinal cord injury and assessed the effects of photobiomodulation treatment.Photobiomodulation effectively cleared damaged mitochondria from endothelial cells in mice,promoting recovery of hindlimb motor function.Using microvascular endothelial bEnd.3 cells subjected to oxygen-glucose deprivation,we found that the effects of photobiomodulation were mediated through activation of the PINK1/Parkin pathway.Additionally,photobiomodulation reduced mitochondrial oxidative stress levels and increased the expression of tight junction proteins within the blood-spinal cord barrier.Our findings suggest that photobiomodulation activates mitochondrial autophagy in endothelial cells through the PINK1/Parkin pathway,thereby promoting repair of the blood-spinal cord barrier following spinal cord injury.
文摘Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.
基金supported by the National Key R&D Program of China,Nos.2017YFA0104302(to NG and XM)and 2017YFA0104304(to BW and ZZ)
文摘Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.
文摘短期预测在智能电网建设中扮演着重要角色,深刻影响电网发输变配用各个环节的智能化改造。短期预测一般基于系统实测数据,而传感器故障,数据传输错误等原因会导致数据质量下降,严重影响短期预测的精确性。为建立数据质量受损情况下的精确短期预测模型,提出了结合数据预处理和双向长短期记忆(bi-directional long short-term memory,Bi-LSTM)的短期预测框架Bi-LSTM-DP(bi-directional long short-term memory data preprocessing)。在Bi-LSTM-DP中,采集的数据首先通过均值填补缺失值,进而基于Savitzky-Golay滤波器对数据降噪,最后采用Bi-LSTM提取时间序列的信息,实现短期预测。为了评估所提方法的性能,文中使用实测的公开数据集分别预测风电发电量和负荷需求,与其他参考方法对比表明了所述方法的有效性和鲁棒性。
