Artificial neural network has been used successfully to develope the automatic spike extraction. In order to address some of the problems before the wireless transmission of the implantable chip, the automatic spike s...Artificial neural network has been used successfully to develope the automatic spike extraction. In order to address some of the problems before the wireless transmission of the implantable chip, the automatic spike sorting method with low complexity and high efficiency is proposed based on the hybrid neural network with the principal component analysis network (PCAN) and normal boundary response (NBR) self-organizing mapping (SOM) net- work classifier. An automatic PCAN technique is used to reduce the dimension and eliminate the correlation of the spike signal. The NBR-SOM network performs the spike sorting challenge and improves the classification performance. The experimental results show that based on the hybrid neural network, the spike sorting method achieves the accuracy above 97.91% with signals contain- ing five classes. The proposed NBR-SOM network classifier is to further improve the stability and effectiveness of the classification system.展开更多
The collected spikes from extracellular recordings usually contain noisy data and outliers, which make it difficult to separate them. A method for spike sorting based on robust clustering is proposed to deal with the ...The collected spikes from extracellular recordings usually contain noisy data and outliers, which make it difficult to separate them. A method for spike sorting based on robust clustering is proposed to deal with the problem. The clustering method combines the advantage of fuzzy clustering and robust statistical estimators. The number of dusters is obtained by fuzzy cluster validity. In order to reduce the influence of outliers, the validity index is calculated using the weighting intra-cluster distances. The proposed method is suitable to separate neural spikes in the presence of noisy data and outfiers. The experiment on real data shows its performance.展开更多
Via an insufficient coat protein complex I(COPI)retrieval signal,the majority of SARSCo V-2 spike(S)is resident in host early secretory organelles and a tiny amount is leaked out in cell surface.Only surface-exposed S...Via an insufficient coat protein complex I(COPI)retrieval signal,the majority of SARSCo V-2 spike(S)is resident in host early secretory organelles and a tiny amount is leaked out in cell surface.Only surface-exposed S can be recognized by B cell receptor(BCR)or anti-S therapeutic monoclonal antibodies(m Abs)that is the trigger step for B cell activation after S m RNA vaccination or infected cell clearance by S m Abs.Now,a drug strategy to promote S host surface exposure is absent.Here,we first combined structural and biochemical analysis to characterize S COPI sorting signals.A potent S COPI sorting inhibitor was then invented,evidently capable of promoting S surface exposure and facilitating infected cell clearance by S antibody-dependent cellular cytotoxicity(ADCC).Importantly,with the inhibitor as a probe,we revealed Omicron BA.1 S is less cell surface exposed than prototypes because of a constellation of S folding mutations,possibly corresponding to its ER chaperone association.Our findings not only suggest COPI is a druggable target against COVID-19,but also highlight SARS-Co V-2 evolution mechanism driven by S folding and trafficking mutations.展开更多
基金supported by the National Natural Science Foundation of China(60971084,61272049)the Science Foundation for the Excellent Youth Scholars of Ministry of Education of China (20091102120046)
文摘Artificial neural network has been used successfully to develope the automatic spike extraction. In order to address some of the problems before the wireless transmission of the implantable chip, the automatic spike sorting method with low complexity and high efficiency is proposed based on the hybrid neural network with the principal component analysis network (PCAN) and normal boundary response (NBR) self-organizing mapping (SOM) net- work classifier. An automatic PCAN technique is used to reduce the dimension and eliminate the correlation of the spike signal. The NBR-SOM network performs the spike sorting challenge and improves the classification performance. The experimental results show that based on the hybrid neural network, the spike sorting method achieves the accuracy above 97.91% with signals contain- ing five classes. The proposed NBR-SOM network classifier is to further improve the stability and effectiveness of the classification system.
基金National Natural Science Foundation of China(No.60375039)
文摘The collected spikes from extracellular recordings usually contain noisy data and outliers, which make it difficult to separate them. A method for spike sorting based on robust clustering is proposed to deal with the problem. The clustering method combines the advantage of fuzzy clustering and robust statistical estimators. The number of dusters is obtained by fuzzy cluster validity. In order to reduce the influence of outliers, the validity index is calculated using the weighting intra-cluster distances. The proposed method is suitable to separate neural spikes in the presence of noisy data and outfiers. The experiment on real data shows its performance.
基金supported by Startup fund program at Beijing University of Chinese Medicine(BUCM)(90011451310011,China)to Wenfu Mathe emergency fund against COVID-19 program at BUCM(1000061223476,China)to Wenfu Mathe innovation team and talents cultivation program of national administration of traditional Chinese medicine(ZYYCXTD-C202006,China)to Wenfu Ma。
文摘Via an insufficient coat protein complex I(COPI)retrieval signal,the majority of SARSCo V-2 spike(S)is resident in host early secretory organelles and a tiny amount is leaked out in cell surface.Only surface-exposed S can be recognized by B cell receptor(BCR)or anti-S therapeutic monoclonal antibodies(m Abs)that is the trigger step for B cell activation after S m RNA vaccination or infected cell clearance by S m Abs.Now,a drug strategy to promote S host surface exposure is absent.Here,we first combined structural and biochemical analysis to characterize S COPI sorting signals.A potent S COPI sorting inhibitor was then invented,evidently capable of promoting S surface exposure and facilitating infected cell clearance by S antibody-dependent cellular cytotoxicity(ADCC).Importantly,with the inhibitor as a probe,we revealed Omicron BA.1 S is less cell surface exposed than prototypes because of a constellation of S folding mutations,possibly corresponding to its ER chaperone association.Our findings not only suggest COPI is a druggable target against COVID-19,but also highlight SARS-Co V-2 evolution mechanism driven by S folding and trafficking mutations.