We present a method for solving partial differential equations using artificial neural networks and an adaptive collocation strategy.In this procedure,a coarse grid of training points is used at the initial training s...We present a method for solving partial differential equations using artificial neural networks and an adaptive collocation strategy.In this procedure,a coarse grid of training points is used at the initial training stages,while more points are added at later stages based on the value of the residual at a larger set of evaluation points.This method increases the robustness of the neural network approximation and can result in significant computational savings,particularly when the solution is non-smooth.Numerical results are presented for benchmark problems for scalar-valued PDEs,namely Poisson and Helmholtz equations,as well as for an inverse acoustics problem.展开更多
3-N-butylphthalide is an ettectwe drug for acute iscemlc stroke. However, its effects on cnromc cerebral ischemia-induced neuronal injury remain poorly understood. Therefore, this study li- gated bilateral carotid art...3-N-butylphthalide is an ettectwe drug for acute iscemlc stroke. However, its effects on cnromc cerebral ischemia-induced neuronal injury remain poorly understood. Therefore, this study li- gated bilateral carotid arteries in 15-month-old rats to simulate chronic cerebral ischemia in aged humans. Aged rats were then intragastrically administered 3-n-butylphthalide. 3-N-butylphtha- lide administration improved the neuronal morphology in the cerebral cortex and hippocampus of rats with chronic cerebral ischemia, increased choline acetyltransferase activity, and decreased malondialdehyde and amyloid beta levels, and greatly improved cognitive function. These findings suggest that 3-n-butylphthalide alleviates oxidative stress caused by chronic cerebral ischemia, improves cholinergic function, and inhibits amyloid beta accumulation, thereby im- proving cerebral neuronal injury and cognitive deficits.展开更多
As an essential plant macronutrient, the low availability of phosphorus （P） in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition...As an essential plant macronutrient, the low availability of phosphorus （P） in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition, remobilization and recycling of phosphate （Pi） to maintain P homeostasis. Spatio-temporal molecular, physiological, and biochemical Pi deficiency responses developed by plants are the consequence of local and systemic sensing and signaling pathways. Pi deficiency is sensed locally by the root system where hormones serve as important signaling components in terms of developmental reprogramming, leading to changes in root system architecture. Root-to-shoot and shoot-to-root signals, delivered through the xylem and phloem, respectively, involving Pi itself, hormones, miRNAs, mRNAs, and sucrose, serve to coordinate Pi deficiency responses at the whole-plant level. A combination of chromatin remodeling, transcriptional and posttranslational events contribute to globally regulating a wide range of Pi deficiency responses. In this review, recent advances are evaluated in terms of progress toward developing a comprehen- sive understanding of the molecular events underlying control over P homeostasis. Application of this knowledge, in terms of developing crop plants having enhanced attributes for P use efficiency, is discussed from the perspective of agricultural sustainability in the face of diminishing global P supplies.展开更多
Fault diagnosis is vital in manufacturing system.However,the first step of the traditional fault diagnosis method is to process the signal,extract the features and then put the features into a selected classifier for ...Fault diagnosis is vital in manufacturing system.However,the first step of the traditional fault diagnosis method is to process the signal,extract the features and then put the features into a selected classifier for classification.The process of feature extraction depends on the experimenters’experience,and the classification rate of the shallow diagnostic model does not achieve satisfactory results.In view of these problems,this paper proposes a method of converting raw signals into twodimensional images.This method can extract the features of the converted two-dimensional images and eliminate the impact of expert’s experience on the feature extraction process.And it follows by proposing an intelligent diagnosis algorithm based on Convolution Neural Network(CNN),which can automatically accomplish the process of the feature extraction and fault diagnosis.The effect of this method is verified by bearing data.The influence of different sample sizes and different load conditions on the diagnostic capability of this method is analyzed.The results show that the proposed method is effective and can meet the timeliness requirements of fault diagnosis.展开更多
文摘We present a method for solving partial differential equations using artificial neural networks and an adaptive collocation strategy.In this procedure,a coarse grid of training points is used at the initial training stages,while more points are added at later stages based on the value of the residual at a larger set of evaluation points.This method increases the robustness of the neural network approximation and can result in significant computational savings,particularly when the solution is non-smooth.Numerical results are presented for benchmark problems for scalar-valued PDEs,namely Poisson and Helmholtz equations,as well as for an inverse acoustics problem.
基金supported by Innovation Team Project of Hubei Province 2011 Plans,No.2011JH-2013CXTT06Momentous Scientific Research Funds of Hubei Provincial Education Ministry,No.D20102101Cultivating Funds of Country’s Projects of Hubei University of Medicine,No.2013GPY03
文摘3-N-butylphthalide is an ettectwe drug for acute iscemlc stroke. However, its effects on cnromc cerebral ischemia-induced neuronal injury remain poorly understood. Therefore, this study li- gated bilateral carotid arteries in 15-month-old rats to simulate chronic cerebral ischemia in aged humans. Aged rats were then intragastrically administered 3-n-butylphthalide. 3-N-butylphtha- lide administration improved the neuronal morphology in the cerebral cortex and hippocampus of rats with chronic cerebral ischemia, increased choline acetyltransferase activity, and decreased malondialdehyde and amyloid beta levels, and greatly improved cognitive function. These findings suggest that 3-n-butylphthalide alleviates oxidative stress caused by chronic cerebral ischemia, improves cholinergic function, and inhibits amyloid beta accumulation, thereby im- proving cerebral neuronal injury and cognitive deficits.
基金supported by grants from the United States Department of AgricultureNational Institute of Food and Agriculture (NIFA 201015479+2 种基金 W.J.L.)the National Natural Science Foundation of China (31025022 H.L.)
文摘As an essential plant macronutrient, the low availability of phosphorus （P） in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition, remobilization and recycling of phosphate （Pi） to maintain P homeostasis. Spatio-temporal molecular, physiological, and biochemical Pi deficiency responses developed by plants are the consequence of local and systemic sensing and signaling pathways. Pi deficiency is sensed locally by the root system where hormones serve as important signaling components in terms of developmental reprogramming, leading to changes in root system architecture. Root-to-shoot and shoot-to-root signals, delivered through the xylem and phloem, respectively, involving Pi itself, hormones, miRNAs, mRNAs, and sucrose, serve to coordinate Pi deficiency responses at the whole-plant level. A combination of chromatin remodeling, transcriptional and posttranslational events contribute to globally regulating a wide range of Pi deficiency responses. In this review, recent advances are evaluated in terms of progress toward developing a comprehen- sive understanding of the molecular events underlying control over P homeostasis. Application of this knowledge, in terms of developing crop plants having enhanced attributes for P use efficiency, is discussed from the perspective of agricultural sustainability in the face of diminishing global P supplies.
基金co-supported by the National Natural Science Foundation of China(No.51775452)Fundamental Research Funds for the Central Universities,China(Nos.2682019CX35 and 2018GF02)Planning Project of Science&Technology Department of Sichuan Province,China(No.2019YFG0353).
文摘Fault diagnosis is vital in manufacturing system.However,the first step of the traditional fault diagnosis method is to process the signal,extract the features and then put the features into a selected classifier for classification.The process of feature extraction depends on the experimenters’experience,and the classification rate of the shallow diagnostic model does not achieve satisfactory results.In view of these problems,this paper proposes a method of converting raw signals into twodimensional images.This method can extract the features of the converted two-dimensional images and eliminate the impact of expert’s experience on the feature extraction process.And it follows by proposing an intelligent diagnosis algorithm based on Convolution Neural Network(CNN),which can automatically accomplish the process of the feature extraction and fault diagnosis.The effect of this method is verified by bearing data.The influence of different sample sizes and different load conditions on the diagnostic capability of this method is analyzed.The results show that the proposed method is effective and can meet the timeliness requirements of fault diagnosis.
