Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by h...Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by honeybee stingers,this study proposed a novel microspike robot.This robot firmly adhered to the tissue surface,enabling direct drug delivery from a hydrogel on its back into the targeted tissue via microspikes.The drug delivery rate was influenced by temperature and could be controlled by an alternating magnetic field.Microrobots could be delivered rapidly through a clinical Ommaya reservoir into the postoperative cavity or ventricle of the skull.The microrobot could be actuated for adhesion and retrieval,with its motion posture and trajectory highly precisely controlled by external magnetic fields.Biological experiments confirmed the excellent biocompatibility and biosafety of the microspike robot and demonstrated its effectiveness in treating gliomas by loading unconventional therapeutic drugs.The proposed microspike robot has significant potential for long-term drug delivery to target gliomas and other future clinical applications.展开更多
Peganum harmala L.(P.harmala)is a significant economic and medicinal plant.The seeds of P.harmala have been extensively utilized in traditional Chinese medicine,Uighur medicine,and Mongolian medicine,as documented in ...Peganum harmala L.(P.harmala)is a significant economic and medicinal plant.The seeds of P.harmala have been extensively utilized in traditional Chinese medicine,Uighur medicine,and Mongolian medicine,as documented in the Drug Standard of the Ministry of Health of China.Twelve novel tryptamine-derived alkaloids(1−12)and eight known compounds(13−20)were isolated from P.harmala seeds.Compounds 1 and 2 represent the first reported instances of tryptamine-derived heteromers,comprising tryptamine and aniline fragments with previously undocumented C-3−N-1′linkage and C-3−C-4′connection,respectively.Compounds 3−5 were identified as indole-quinazoline heteromers,exhibiting a novel C-3 and NH-1′linkage between indole and quinazoline-derived fragments.Compound 6 demonstrates the dimerization pattern of C-C linked tryptamine-quinazoline dimer.Compound 8 represents a tryptamine-derived heterodimer with a distinctive carbon skeleton,featuring an unusual spiro-tricyclic ring(7)and conventional bicyclic tryptamine.Compounds 9−11 constitute novel 6/5/5/5 spiro-tetracyclic tryptamine-derived alkaloids presenting a unique ring system of tryptamine-spiro-pyrrolizine.Compounds 1−3 and 6−11 were identified as racemates.Compounds 2,7,9,10,and 12 were confirmed via X-ray crystallographic analysis.All isolated compounds(1−20)exhibited varying degrees of antiviral efficacy against respiratory syncytial virus(RSV).Notably,the anti-RSV activity of compound 12(IC505.01±0.14μmol·L^(−1))surpassed that of the positive control(ribavirin,IC506.23±0.95μmol·L^(−1)),as validated through plaque reduction and immunofluorescence assays.The identification of anti-RSV compounds from P.harmala seeds may enhance the development and application of this plant in antiviral therapeutic products.展开更多
近年来大数据及云计算技术、人工智能技术的发展,使得K-Means聚类算法、DBSCAN聚类算法、BIRCH聚类算法、Cluster数据分布算法不断涌现,但不同算法在面对海量化、多样化网络数据样本时的性能存在差异。基于此,从不同数据文本关联性、数...近年来大数据及云计算技术、人工智能技术的发展,使得K-Means聚类算法、DBSCAN聚类算法、BIRCH聚类算法、Cluster数据分布算法不断涌现,但不同算法在面对海量化、多样化网络数据样本时的性能存在差异。基于此,从不同数据文本关联性、数据集资源的海量性角度出发,利用云计算Spark分布式架构、HDFS(Hadoop Distributed FileSystem)分布式文件系统、Spark SQL数据计算引擎、YARN(Yet Another Resource Negotiator)资源管理器等软件,建构起融合K-Means聚类算法、BIRCH(Balanced Iterative Reducing and Clustering using Hierarchies)聚类算法的数据挖掘模型,根据CF树聚类的判别函数确定被测试数据集的类别,由Spark计算模型将完成聚类的数据集分布式缓存至网络节点内存中,以实现对海量化网络数据的挖掘、聚类及存储操作。展开更多
The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which ...The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which brings about large-scale data processing requirements,edge computing architecture has become an emerging network architecture to support IoT applications due to its ability to provide powerful computing capabilities and good service functions.However,the defense mechanism of Edge Computing-enabled IoT Nodes(ECIoTNs)is still weak due to their limited resources,so that they are susceptible to malicious software spread,which can compromise data confidentiality and network service availability.Facing this situation,we put forward an epidemiology-based susceptible-curb-infectious-removed-dead(SCIRD)model.Then,we analyze the dynamics of ECIoTNs with different infection levels under different initial conditions to obtain the dynamic differential equations.Additionally,we establish the presence of equilibrium states in the SCIRD model.Furthermore,we conduct an analysis of the model’s stability and examine the conditions under which malicious software will either spread or disappear within Edge Computing-enabled IoT(ECIoT)networks.Lastly,we validate the efficacy and superiority of the SCIRD model through MATLAB simulations.These research findings offer a theoretical foundation for suppressing the propagation of malicious software in ECIoT networks.The experimental results indicate that the theoretical SCIRD model has instructive significance,deeply revealing the principles of malicious software propagation in ECIoT networks.This study solves a challenging security problem of ECIoT networks by determining the malicious software propagation threshold,which lays the foundation for buildingmore secure and reliable ECIoT networks.展开更多
基金supported by the National Key R&D Program of China(No.2023YFB4705600)the National Natural Science Foundation of China(Nos.U23A20342,62273331,61925307,and 61821005)+1 种基金the CAS Project for Young Scientists in Basic Research(No.YSBR-036)the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by honeybee stingers,this study proposed a novel microspike robot.This robot firmly adhered to the tissue surface,enabling direct drug delivery from a hydrogel on its back into the targeted tissue via microspikes.The drug delivery rate was influenced by temperature and could be controlled by an alternating magnetic field.Microrobots could be delivered rapidly through a clinical Ommaya reservoir into the postoperative cavity or ventricle of the skull.The microrobot could be actuated for adhesion and retrieval,with its motion posture and trajectory highly precisely controlled by external magnetic fields.Biological experiments confirmed the excellent biocompatibility and biosafety of the microspike robot and demonstrated its effectiveness in treating gliomas by loading unconventional therapeutic drugs.The proposed microspike robot has significant potential for long-term drug delivery to target gliomas and other future clinical applications.
基金supported by the National Natural Science Foundation of China(Nos.82104015,82003609,and 81973190)the Guangdong Basic and Applied Basic Research Foundation(Nos.2020A1515110415,2020A1515110453,and 2020B1515020033)+1 种基金the Characteristic Innovation Project of General Universities in Guangdong Province(No.2024KTSCX167)the Science and Technology Planning Project of Guangzhou City(No.202201010485).
文摘Peganum harmala L.(P.harmala)is a significant economic and medicinal plant.The seeds of P.harmala have been extensively utilized in traditional Chinese medicine,Uighur medicine,and Mongolian medicine,as documented in the Drug Standard of the Ministry of Health of China.Twelve novel tryptamine-derived alkaloids(1−12)and eight known compounds(13−20)were isolated from P.harmala seeds.Compounds 1 and 2 represent the first reported instances of tryptamine-derived heteromers,comprising tryptamine and aniline fragments with previously undocumented C-3−N-1′linkage and C-3−C-4′connection,respectively.Compounds 3−5 were identified as indole-quinazoline heteromers,exhibiting a novel C-3 and NH-1′linkage between indole and quinazoline-derived fragments.Compound 6 demonstrates the dimerization pattern of C-C linked tryptamine-quinazoline dimer.Compound 8 represents a tryptamine-derived heterodimer with a distinctive carbon skeleton,featuring an unusual spiro-tricyclic ring(7)and conventional bicyclic tryptamine.Compounds 9−11 constitute novel 6/5/5/5 spiro-tetracyclic tryptamine-derived alkaloids presenting a unique ring system of tryptamine-spiro-pyrrolizine.Compounds 1−3 and 6−11 were identified as racemates.Compounds 2,7,9,10,and 12 were confirmed via X-ray crystallographic analysis.All isolated compounds(1−20)exhibited varying degrees of antiviral efficacy against respiratory syncytial virus(RSV).Notably,the anti-RSV activity of compound 12(IC505.01±0.14μmol·L^(−1))surpassed that of the positive control(ribavirin,IC506.23±0.95μmol·L^(−1)),as validated through plaque reduction and immunofluorescence assays.The identification of anti-RSV compounds from P.harmala seeds may enhance the development and application of this plant in antiviral therapeutic products.
文摘近年来大数据及云计算技术、人工智能技术的发展,使得K-Means聚类算法、DBSCAN聚类算法、BIRCH聚类算法、Cluster数据分布算法不断涌现,但不同算法在面对海量化、多样化网络数据样本时的性能存在差异。基于此,从不同数据文本关联性、数据集资源的海量性角度出发,利用云计算Spark分布式架构、HDFS(Hadoop Distributed FileSystem)分布式文件系统、Spark SQL数据计算引擎、YARN(Yet Another Resource Negotiator)资源管理器等软件,建构起融合K-Means聚类算法、BIRCH(Balanced Iterative Reducing and Clustering using Hierarchies)聚类算法的数据挖掘模型,根据CF树聚类的判别函数确定被测试数据集的类别,由Spark计算模型将完成聚类的数据集分布式缓存至网络节点内存中,以实现对海量化网络数据的挖掘、聚类及存储操作。
基金in part by National Undergraduate Innovation and Entrepreneurship Training Program under Grant No.202310347039Zhejiang Provincial Natural Science Foundation of China under Grant No.LZ22F020002Huzhou Science and Technology Planning Foundation under Grant No.2023GZ04.
文摘The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which brings about large-scale data processing requirements,edge computing architecture has become an emerging network architecture to support IoT applications due to its ability to provide powerful computing capabilities and good service functions.However,the defense mechanism of Edge Computing-enabled IoT Nodes(ECIoTNs)is still weak due to their limited resources,so that they are susceptible to malicious software spread,which can compromise data confidentiality and network service availability.Facing this situation,we put forward an epidemiology-based susceptible-curb-infectious-removed-dead(SCIRD)model.Then,we analyze the dynamics of ECIoTNs with different infection levels under different initial conditions to obtain the dynamic differential equations.Additionally,we establish the presence of equilibrium states in the SCIRD model.Furthermore,we conduct an analysis of the model’s stability and examine the conditions under which malicious software will either spread or disappear within Edge Computing-enabled IoT(ECIoT)networks.Lastly,we validate the efficacy and superiority of the SCIRD model through MATLAB simulations.These research findings offer a theoretical foundation for suppressing the propagation of malicious software in ECIoT networks.The experimental results indicate that the theoretical SCIRD model has instructive significance,deeply revealing the principles of malicious software propagation in ECIoT networks.This study solves a challenging security problem of ECIoT networks by determining the malicious software propagation threshold,which lays the foundation for buildingmore secure and reliable ECIoT networks.
