Accurately predicting fatigue life under multiaxial fatigue damage conditions is essential for ensuring the safety of critical components in service.However,due to the complexity of fatigue failure mechanisms,achievin...Accurately predicting fatigue life under multiaxial fatigue damage conditions is essential for ensuring the safety of critical components in service.However,due to the complexity of fatigue failure mechanisms,achieving accurate multiaxial fatigue life predictions remains challenging.Traditional multiaxial fatigue prediction models are often limited by specific material properties and loading conditions,making it difficult to maintain reliable life prediction results beyond these constraints.This paper presents a study on the impact of seven key feature quantities on multiaxial fatigue life,using Convolutional Neural Networks(CNN),Long Short-Term Memory Networks(LSTM),and Fully Connected Neural Networks(FCNN)within a deep learning framework.Fatigue test results from eight metal specimens were analyzed to identify these feature quantities,which were then extracted as critical time-series features.Using a CNN-LSTM network,these features were combined to form a feature matrix,which was subsequently input into an FCNN to predict metal fatigue life.A comparison of the fatigue life prediction results from the STFAN model with those from traditional prediction models—namely,the equivalent strain method,the maximum shear strain method,and the critical plane method—shows that the majority of predictions for the five metal materials and various loading conditions based on the STFAN model fall within an error band of 1.5 times.Additionally,all data points are within an error band of 2 times.These findings indicate that the STFAN model provides superior prediction accuracy compared to the traditional models,highlighting its broad applicability and high precision.展开更多
With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely o...With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.展开更多
Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily...Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily involving abnormal development and damage of the dopaminergic system,pose significant public health challenges.Microglia,as the primary immune cells in the brain,are crucial in regulating neuronal circuit development and survival.From the embryonic stage to adulthood,microglia exhibit stage-specific gene expression profiles,transcriptome characteristics,and functional phenotypes,enhancing the susceptibility to early life stress.However,the role of microglia in mediating dopaminergic system disorders under early life stress conditions remains poorly understood.This review presents an up-to-date overview of preclinical studies elucidating the impact of early life stress on microglia,leading to dopaminergic system disorders,along with the underlying mechanisms and therapeutic potential for neurodegenerative and neurodevelopmental conditions.Impaired microglial activity damages dopaminergic neurons by diminishing neurotrophic support(e.g.,insulin-like growth factor-1)and hinders dopaminergic axon growth through defective phagocytosis and synaptic pruning.Furthermore,blunted microglial immunoreactivity suppresses striatal dopaminergic circuit development and reduces neuronal transmission.Furthermore,inflammation and oxidative stress induced by activated microglia can directly damage dopaminergic neurons,inhibiting dopamine synthesis,reuptake,and receptor activity.Enhanced microglial phagocytosis inhibits dopamine axon extension.These long-lasting effects of microglial perturbations may be driven by early life stress–induced epigenetic reprogramming of microglia.Indirectly,early life stress may influence microglial function through various pathways,such as astrocytic activation,the hypothalamic–pituitary–adrenal axis,the gut–brain axis,and maternal immune signaling.Finally,various therapeutic strategies and molecular mechanisms for targeting microglia to restore the dopaminergic system were summarized and discussed.These strategies include classical antidepressants and antipsychotics,antibiotics and anti-inflammatory agents,and herbal-derived medicine.Further investigations combining pharmacological interventions and genetic strategies are essential to elucidate the causal role of microglial phenotypic and functional perturbations in the dopaminergic system disrupted by early life stress.展开更多
基金supported by Key Program of National Natural Science Foundation of China(U2368215)the Science and Technology Research and Development Program Project of China Railway Group Co.,Ltd.(N2023J056).
文摘Accurately predicting fatigue life under multiaxial fatigue damage conditions is essential for ensuring the safety of critical components in service.However,due to the complexity of fatigue failure mechanisms,achieving accurate multiaxial fatigue life predictions remains challenging.Traditional multiaxial fatigue prediction models are often limited by specific material properties and loading conditions,making it difficult to maintain reliable life prediction results beyond these constraints.This paper presents a study on the impact of seven key feature quantities on multiaxial fatigue life,using Convolutional Neural Networks(CNN),Long Short-Term Memory Networks(LSTM),and Fully Connected Neural Networks(FCNN)within a deep learning framework.Fatigue test results from eight metal specimens were analyzed to identify these feature quantities,which were then extracted as critical time-series features.Using a CNN-LSTM network,these features were combined to form a feature matrix,which was subsequently input into an FCNN to predict metal fatigue life.A comparison of the fatigue life prediction results from the STFAN model with those from traditional prediction models—namely,the equivalent strain method,the maximum shear strain method,and the critical plane method—shows that the majority of predictions for the five metal materials and various loading conditions based on the STFAN model fall within an error band of 1.5 times.Additionally,all data points are within an error band of 2 times.These findings indicate that the STFAN model provides superior prediction accuracy compared to the traditional models,highlighting its broad applicability and high precision.
文摘With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.
基金supported by the National Natural Science Foundation of China,Nos.82304990(to NY),81973748(to JC),82174278(to JC)the National Key R&D Program of China,No.2023YFE0209500(to JC)+4 种基金China Postdoctoral Science Foundation,No.2023M732380(to NY)Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine,No.202102010014(to JC)Huang Zhendong Research Fund for Traditional Chinese Medicine of Jinan University,No.201911(to JC)National Innovation and Entrepreneurship Training Program for Undergraduates in China,No.202310559128(to NY and QM)Innovation and Entrepreneurship Training Program for Undergraduates at Jinan University,Nos.CX24380,CX24381(both to NY and QM)。
文摘Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily involving abnormal development and damage of the dopaminergic system,pose significant public health challenges.Microglia,as the primary immune cells in the brain,are crucial in regulating neuronal circuit development and survival.From the embryonic stage to adulthood,microglia exhibit stage-specific gene expression profiles,transcriptome characteristics,and functional phenotypes,enhancing the susceptibility to early life stress.However,the role of microglia in mediating dopaminergic system disorders under early life stress conditions remains poorly understood.This review presents an up-to-date overview of preclinical studies elucidating the impact of early life stress on microglia,leading to dopaminergic system disorders,along with the underlying mechanisms and therapeutic potential for neurodegenerative and neurodevelopmental conditions.Impaired microglial activity damages dopaminergic neurons by diminishing neurotrophic support(e.g.,insulin-like growth factor-1)and hinders dopaminergic axon growth through defective phagocytosis and synaptic pruning.Furthermore,blunted microglial immunoreactivity suppresses striatal dopaminergic circuit development and reduces neuronal transmission.Furthermore,inflammation and oxidative stress induced by activated microglia can directly damage dopaminergic neurons,inhibiting dopamine synthesis,reuptake,and receptor activity.Enhanced microglial phagocytosis inhibits dopamine axon extension.These long-lasting effects of microglial perturbations may be driven by early life stress–induced epigenetic reprogramming of microglia.Indirectly,early life stress may influence microglial function through various pathways,such as astrocytic activation,the hypothalamic–pituitary–adrenal axis,the gut–brain axis,and maternal immune signaling.Finally,various therapeutic strategies and molecular mechanisms for targeting microglia to restore the dopaminergic system were summarized and discussed.These strategies include classical antidepressants and antipsychotics,antibiotics and anti-inflammatory agents,and herbal-derived medicine.Further investigations combining pharmacological interventions and genetic strategies are essential to elucidate the causal role of microglial phenotypic and functional perturbations in the dopaminergic system disrupted by early life stress.
