Deciphering the metabolites of multiple components in herbal medicine has far-reaching significance for revealing pharmacodynamic ingredients.However,most chemical components of herbal medicine are secondary metabolit...Deciphering the metabolites of multiple components in herbal medicine has far-reaching significance for revealing pharmacodynamic ingredients.However,most chemical components of herbal medicine are secondary metabolites with low content whose in vivo metabolites are close to trace amounts,making it difficult to achieve comprehensive detection and identification.In this paper,an efficient strategy was proposed:herb-derived metabolites were predicted according to the structural characteristics and metabolic reactions of chemical constituents in Corydalis Rhizoma and chemical structure screening tables for metabolites were conducted.The fragmentation patterns were summarized from representative standards combining with specific cleavage behaviors to deduce structures of metabolites.Ion abundance plays an important role in compound identification,and high ion abundance can improve identification accuracy.The types of metabolites in different biological samples were very similar,but their ion abundance might be different.Therefore,for trace metabolites in biological samples,we used the following two methods to process:metabolites of high dose herbal extract were analyzed to characterize those of clinical dose herbal extracts in the same biological samples;cross-mapping of different biological samples was applied to identify trace metabolites based on the fact that a metabolite has different ion abundance in different biological samples.Compared with not using this strategy,44 more metabolites of clinical dose herbal extract were detected.This study improved the depth,breadth,and accuracy of current methods for herb-derived metabolites characterization.展开更多
Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set...Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set in the network.Due to the characteristics of global perspective,control data separation,and centralized control of SDN,the idea of SDN is introduced to the design of the satellite network model.As a result,satellite nodes are only responsible for data transmission,while the maintenance of the links and the calculation of routes are implemented by the controller.For the massive LEO satellite network based on SDN,a state evaluation decision routing mechanism is proposed.The designed mechanism monitors the status of the entire network effectively and reduces the on-board load on the satellite network.The best routing decision is made under the comprehensive consideration of the current and historical status of each inter-satellite link between Low Earth Orbit(LEO)satellite network nodes.The calculation and storage requirements are controlled within a reasonable range.Based on the curve parameter transmission fuzzy encryption algorithm,a safe and reliable condition assessment decision routing mechanism(CADRM)is designed.It ensures that the personal information of the LEO satellite network can be transmitted safely and effectively.The experimental simulation results show the improvement of network throughput,the reduction of packet loss rate and the enhancing of network reliability.展开更多
文摘Deciphering the metabolites of multiple components in herbal medicine has far-reaching significance for revealing pharmacodynamic ingredients.However,most chemical components of herbal medicine are secondary metabolites with low content whose in vivo metabolites are close to trace amounts,making it difficult to achieve comprehensive detection and identification.In this paper,an efficient strategy was proposed:herb-derived metabolites were predicted according to the structural characteristics and metabolic reactions of chemical constituents in Corydalis Rhizoma and chemical structure screening tables for metabolites were conducted.The fragmentation patterns were summarized from representative standards combining with specific cleavage behaviors to deduce structures of metabolites.Ion abundance plays an important role in compound identification,and high ion abundance can improve identification accuracy.The types of metabolites in different biological samples were very similar,but their ion abundance might be different.Therefore,for trace metabolites in biological samples,we used the following two methods to process:metabolites of high dose herbal extract were analyzed to characterize those of clinical dose herbal extracts in the same biological samples;cross-mapping of different biological samples was applied to identify trace metabolites based on the fact that a metabolite has different ion abundance in different biological samples.Compared with not using this strategy,44 more metabolites of clinical dose herbal extract were detected.This study improved the depth,breadth,and accuracy of current methods for herb-derived metabolites characterization.
基金This work is supported by Fundamental Research Funds for the Central Universities of China(328201911),C.G.(Chao Guo)the Open Project Program of National Engineering Laboratory for Agri-product Quality Traceability,C.G.(Chao Guo),Beijing Technology and Business University(BTBU)No.AQT-2018Y-B4,C.G.(Chao Guo)Higher Education Department of the Ministry of Education Industry-university Cooperative Education Project,C.G.(Chao Guo),and Education and Teaching Reform Project of Beijing Electronic and Technology Institute,C.G.(Chao Guo).
文摘Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set in the network.Due to the characteristics of global perspective,control data separation,and centralized control of SDN,the idea of SDN is introduced to the design of the satellite network model.As a result,satellite nodes are only responsible for data transmission,while the maintenance of the links and the calculation of routes are implemented by the controller.For the massive LEO satellite network based on SDN,a state evaluation decision routing mechanism is proposed.The designed mechanism monitors the status of the entire network effectively and reduces the on-board load on the satellite network.The best routing decision is made under the comprehensive consideration of the current and historical status of each inter-satellite link between Low Earth Orbit(LEO)satellite network nodes.The calculation and storage requirements are controlled within a reasonable range.Based on the curve parameter transmission fuzzy encryption algorithm,a safe and reliable condition assessment decision routing mechanism(CADRM)is designed.It ensures that the personal information of the LEO satellite network can be transmitted safely and effectively.The experimental simulation results show the improvement of network throughput,the reduction of packet loss rate and the enhancing of network reliability.