There are various heterogeneous networks for terminals to deliver a better quality of service. Signal system recognition and classification contribute a lot to the process. However, in low signal to noise ratio(SNR)...There are various heterogeneous networks for terminals to deliver a better quality of service. Signal system recognition and classification contribute a lot to the process. However, in low signal to noise ratio(SNR) circumstances or under time-varying multipath channels, the majority of the existing algorithms for signal recognition are already facing limitations. In this series, we present a robust signal recognition method based upon the original and latest updated version of the extreme learning machine(ELM) to help users to switch between networks. The ELM utilizes signal characteristics to distinguish systems. The superiority of this algorithm lies in the random choices of hidden nodes and in the fact that it determines the output weights analytically, which result in lower complexity. Theoretically, the algorithm tends to offer a good generalization performance at an extremely fast speed of learning. Moreover, we implement the GSM/WCDMA/LTE models in the Matlab environment by using the Simulink tools. The simulations reveal that the signals can be recognized successfully to achieve a 95% accuracy in a low SNR(0 dB) environment in the time-varying multipath Rayleigh fading channel.展开更多
As populations age, prevalence of Alzheimer's disease(AD) is rising. Over 100 years of research has provided valuable insights into the pathophysiology of the disease, for which age is the principal risk factor. Ho...As populations age, prevalence of Alzheimer's disease(AD) is rising. Over 100 years of research has provided valuable insights into the pathophysiology of the disease, for which age is the principal risk factor. However, in recent years, a multitude of clinical trial failures has led to pharmaceutical corporations becoming more and more unwilling to support drug development in AD. It is possible that dependence on the amyloid cascade hypothesis as a guide for preclinical research and drug discovery is part of the problem. Accumulating evidence suggests that amyloid plaques and tau tangles are evident in non-demented individuals and that reducing or clearing these lesions does not always result in clinical improvement. Normal aging is associated with pathologies and cognitive decline that are similar to those observed in AD, making differentiation of AD-related cognitive decline and neuropathology challenging. In this mini-review, we discuss the difficulties with discerning normal, age-related cognitive decline with that related to AD. We also discuss some neuropathological features of AD and aging, including amyloid and tau pathology, synapse loss, inflammation and insulin signaling in the brain, with a view to highlighting cognitive or neuropathological markers that distinguish AD from normal aging. It is hoped that this review will help to bolster future preclinical research and support the development of clinical tools and therapeutics for AD.展开更多
Objective:To determine the effects of 5-hydroxymethyl furfural(5-HMF),an extract of Rehmannia glutinosa Libosch,on several down-regulated signaling molecules involved in learning and memory in hippocampal neurons.M...Objective:To determine the effects of 5-hydroxymethyl furfural(5-HMF),an extract of Rehmannia glutinosa Libosch,on several down-regulated signaling molecules involved in learning and memory in hippocampal neurons.Methods:After cultured for 7 days,primary hippocampal neurons were divided into 5 groups:normal,corticosterone model,RU38486,5-HMF,and donepezil group.Neuron survival rates were calculated 24 h later using SYT013-P1 double-fluorescence staining and an 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.β-galactosidase activity was also assayed.Protein expressed by the glucocorticoid receptor(GCR),brainderived neurotrophic factor(BDNF),and N-methyl-D-aspartate receptor 2B(NR2B),as well as phosphorylationcyclic adenosine monophosphate(cAMP)response element binding protein(p-CREB),phosphorylation-extracellular signal-regulated kinase(p-ERK),and phosphorylation-synapsin(p-synapsin)were quantified with Western blot.Results:Hippocampal neuron survival rates and the above-mentioned proteins were dramatically decreased(P〈0.05),β-galactosidase activity was significantly increased in the model group,but the effect was reversed by5-HMF,RU38486,and to a lesser extent by donepezil(P〈0.05).Conclusion:5-HMF extracts from the Chinese herb Rehmannia glutinosa Libosch could protect hippocampal neurons from glucocorticoid injury and from down-regulated signaling molecules in the GCR-BDNF-NR2B-p-ERK-p-CREB-p-synapsin signal transduction pathway.展开更多
Animals can sense many environment stimuli simultaneously and integrate these signals within the nervous system. However, the neural system and molecular
Epilepsy is the most common neurological disorder of the brain that affects people worldwide at any age from newborn to adult. It is characterized by recurrent seizures, which are brief episodes of signs or symptoms d...Epilepsy is the most common neurological disorder of the brain that affects people worldwide at any age from newborn to adult. It is characterized by recurrent seizures, which are brief episodes of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. The electroencephalogram, or EEG, is a physiological method to measure and record the electrical展开更多
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(2014 ZX03001027)
文摘There are various heterogeneous networks for terminals to deliver a better quality of service. Signal system recognition and classification contribute a lot to the process. However, in low signal to noise ratio(SNR) circumstances or under time-varying multipath channels, the majority of the existing algorithms for signal recognition are already facing limitations. In this series, we present a robust signal recognition method based upon the original and latest updated version of the extreme learning machine(ELM) to help users to switch between networks. The ELM utilizes signal characteristics to distinguish systems. The superiority of this algorithm lies in the random choices of hidden nodes and in the fact that it determines the output weights analytically, which result in lower complexity. Theoretically, the algorithm tends to offer a good generalization performance at an extremely fast speed of learning. Moreover, we implement the GSM/WCDMA/LTE models in the Matlab environment by using the Simulink tools. The simulations reveal that the signals can be recognized successfully to achieve a 95% accuracy in a low SNR(0 dB) environment in the time-varying multipath Rayleigh fading channel.
基金supported by the Department of Education and Learning,Northern Ireland,UK
文摘As populations age, prevalence of Alzheimer's disease(AD) is rising. Over 100 years of research has provided valuable insights into the pathophysiology of the disease, for which age is the principal risk factor. However, in recent years, a multitude of clinical trial failures has led to pharmaceutical corporations becoming more and more unwilling to support drug development in AD. It is possible that dependence on the amyloid cascade hypothesis as a guide for preclinical research and drug discovery is part of the problem. Accumulating evidence suggests that amyloid plaques and tau tangles are evident in non-demented individuals and that reducing or clearing these lesions does not always result in clinical improvement. Normal aging is associated with pathologies and cognitive decline that are similar to those observed in AD, making differentiation of AD-related cognitive decline and neuropathology challenging. In this mini-review, we discuss the difficulties with discerning normal, age-related cognitive decline with that related to AD. We also discuss some neuropathological features of AD and aging, including amyloid and tau pathology, synapse loss, inflammation and insulin signaling in the brain, with a view to highlighting cognitive or neuropathological markers that distinguish AD from normal aging. It is hoped that this review will help to bolster future preclinical research and support the development of clinical tools and therapeutics for AD.
基金Support by the National Natural Science Foundation of China(No.30873317),Leading Academic Discipline Project of Shanghai Municipal Education Commission(No.J50301),Shanghai Health Bureau of Scientific Research Projects(No.20124Y025)
文摘Objective:To determine the effects of 5-hydroxymethyl furfural(5-HMF),an extract of Rehmannia glutinosa Libosch,on several down-regulated signaling molecules involved in learning and memory in hippocampal neurons.Methods:After cultured for 7 days,primary hippocampal neurons were divided into 5 groups:normal,corticosterone model,RU38486,5-HMF,and donepezil group.Neuron survival rates were calculated 24 h later using SYT013-P1 double-fluorescence staining and an 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.β-galactosidase activity was also assayed.Protein expressed by the glucocorticoid receptor(GCR),brainderived neurotrophic factor(BDNF),and N-methyl-D-aspartate receptor 2B(NR2B),as well as phosphorylationcyclic adenosine monophosphate(cAMP)response element binding protein(p-CREB),phosphorylation-extracellular signal-regulated kinase(p-ERK),and phosphorylation-synapsin(p-synapsin)were quantified with Western blot.Results:Hippocampal neuron survival rates and the above-mentioned proteins were dramatically decreased(P〈0.05),β-galactosidase activity was significantly increased in the model group,but the effect was reversed by5-HMF,RU38486,and to a lesser extent by donepezil(P〈0.05).Conclusion:5-HMF extracts from the Chinese herb Rehmannia glutinosa Libosch could protect hippocampal neurons from glucocorticoid injury and from down-regulated signaling molecules in the GCR-BDNF-NR2B-p-ERK-p-CREB-p-synapsin signal transduction pathway.
文摘Animals can sense many environment stimuli simultaneously and integrate these signals within the nervous system. However, the neural system and molecular
文摘Epilepsy is the most common neurological disorder of the brain that affects people worldwide at any age from newborn to adult. It is characterized by recurrent seizures, which are brief episodes of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. The electroencephalogram, or EEG, is a physiological method to measure and record the electrical