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Causal genetic regulation of DNA replication on immune microenvironment in colorectal tumorigenesis: Evidenced by an integrated approach of trans-omics and GWAS
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作者 Sumeng Wang Silu Chen +6 位作者 Huiqin Li Shuai Ben Tingyu Zhao Rui Zheng Meilin Wang Dongying Gu Lingxiang Liu 《The Journal of Biomedical Research》 CAS CSCD 2024年第1期37-50,共14页
The interplay between DNA replication stress and immune microenvironment alterations is known to play a crucial role in colorectal tumorigenesis,but a comprehensive understanding of their association with and relevant... The interplay between DNA replication stress and immune microenvironment alterations is known to play a crucial role in colorectal tumorigenesis,but a comprehensive understanding of their association with and relevant biomarkers involved in colorectal tumorigenesis is lacking.To address this gap,we conducted a study aiming to investigate this association and identify relevant biomarkers.We analyzed transcriptomic and proteomic profiles of 904 colorectal tumor tissues and 342 normal tissues to examine pathway enrichment,biological activity,and the immune microenvironment.Additionally,we evaluated genetic effects of single variants and genes on colorectal cancer susceptibility using data from genome-wide association studies(GWASs)involving both East Asian(7062 cases and 195745 controls)and European(24476 cases and 23073 controls)populations.We employed mediation analysis to infer the causal pathway,and applied multiplex immunofluorescence to visualize colocalized biomarkers in colorectal tumors and immune cells.Our findings revealed that both DNA replication activity and the flap structure-specific endonuclease 1(FEN1)gene were significantly enriched in colorectal tumor tissues,compared with normal tissues.Moreover,a genetic variant rs4246215 G>T in FEN1 was associated with a decreased risk of colorectal cancer(odds ratio=0.94,95%confidence interval:0.90–0.97,P_(meta)=4.70×10^(-9)).Importantly,we identified basophils and eosinophils that both exhibited a significantly decreased infiltration in colorectal tumors,and were regulated by rs4246215 through causal pathways involving both FEN1 and DNA replication.In conclusion,this trans-omics incorporating GWAS data provides insights into a plausible pathway connecting DNA replication and immunity,expanding biological knowledge of colorectal tumorigenesis and therapeutic targets. 展开更多
关键词 trans-omics DNA replication tumor immune microenvironment causal mediation colorectal tumorigenesis
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Statistical Method for Block in Replication Design and Its SAS Program 被引量:1
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作者 Ning Hai-long Wang Jia-jing +8 位作者 Hu Bo Ge Tong Shan Da-rui Dong Sheng Shi Da-liang Xue Hong Yuan Ming Dong Quan-zhong Li Wen-xia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期37-43,共7页
Large-scale genetic population used for genetic breeding researches covers a large area in the field experiment,and the effect of local control would be gradually weakened.The block in replication(BIR)design is suitab... Large-scale genetic population used for genetic breeding researches covers a large area in the field experiment,and the effect of local control would be gradually weakened.The block in replication(BIR)design is suitable for large population,which is applied to the field experiment of genetic population.The statistical methods of analysis of variance(ANOVA)and heritability estimation in single and multiple environments were derived and implemented using the statistical analysis system(SAS)program for the analysis of BIR.As a work example,a comparison of statistical analysis between BIR design and the completely random block(CRB)design were conducted for the protein content from a panel containing 455 soybean germplasms.The results indicated the different estimates of average heritability in multiple environments.The research results provided technical support for the application of BIR design in genetics and breeding studies. 展开更多
关键词 block in replication(BIR) multi-environment joint analysis analysis of variance HERITABILITY SAS program
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Transcriptional regulation of secondary metabolism and autophagy genes in response to DNA replication stress in Setosphaeria turcica
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作者 MENG Ya-nan ZHANG Xin-jie +8 位作者 ZENG Fan-li ZHAI Wei-bo LI Pan HU Jing-jing XIAO Sheng-lin HAO Zhi-min CAO Zhi-yan CHEN Chuan DONG Jin-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1068-1081,共14页
The fungal pathogen Setosphaeria turcica causes northern corn leaf blight(NCLB),which leads to considerable crop losses.Setosphaeria turcica elaborates a specialized infection structures called appressorium for maize ... The fungal pathogen Setosphaeria turcica causes northern corn leaf blight(NCLB),which leads to considerable crop losses.Setosphaeria turcica elaborates a specialized infection structures called appressorium for maize infection.Previously,we demonstrated that the S.turcica triggers an S-phase checkpoint and ATR(Ataxia Telangiectasia and Rad3 related)-dependent self-protective response to DNA genotoxic insults during maize infection.However,how the regulatory mechanism works was still largely unknown.Here,we report a genome wide transcriptional profile analysis during appressorium formation in the present of DNA replication stress.We performed RNA-Seq analysis to identify S.tuicica genes responsive to DNA replication stress.In the current work,we found that appressorium-mediated maize infection by S.turcica is significantly blocked by S-phase checkpoint.A large serial of secondary metabolite and melanin biosynthesis genes were blocked in appressorium formation of S.turcica during the replication stress.The secondary metabolite biosynthesis genes including alcohol dehydrogenase GroES-like domain,multicopper oxidase,ABCtransporter families,cytochrome P450 and FAD-containing monooxygenase were related to plant pathogen infection.In addition,we demonstrated that autophagy in S.turcica is up-regulated by ATR as a defense response to stress.We identified StATG3,StATG4,StATG5,StATG7 and StATG16 genes for autophagy were induced by ATR-mediated S-phase checkpoint.We therefore propose that in response to genotoxic stress,S.turcica utilizes ATR-dependent pathway to turn off transcription of genes governing appressorium-mediated infection,and meanwhile inducing transcription of autophagy genes likely as a mechanism of self-protection,aside from the more conservative responses in eukaryotes. 展开更多
关键词 Setosphaeria turcica APPRESSORIUM secondary metabolite AUTOPHAGY DNA replication stress
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Replication Strategy with Comprehensive Data Center Selection Method in Cloud Environments
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作者 M.A.Fazlina Rohaya Latip +1 位作者 Hamidah Ibrahim Azizol Abdullah 《Computers, Materials & Continua》 SCIE EI 2023年第1期415-433,共19页
As the amount of data continues to grow rapidly,the variety of data produced by applications is becoming more affluent than ever.Cloud computing is the best technology evolving today to provide multi-services for the ... As the amount of data continues to grow rapidly,the variety of data produced by applications is becoming more affluent than ever.Cloud computing is the best technology evolving today to provide multi-services for the mass and variety of data.The cloud computing features are capable of processing,managing,and storing all sorts of data.Although data is stored in many high-end nodes,either in the same data centers or across many data centers in cloud,performance issues are still inevitable.The cloud replication strategy is one of best solutions to address risk of performance degradation in the cloud environment.The real challenge here is developing the right data replication strategy with minimal data movement that guarantees efficient network usage,low fault tolerance,and minimal replication frequency.The key problem discussed in this research is inefficient network usage discovered during selecting a suitable data center to store replica copies induced by inadequate data center selection criteria.Hence,to mitigate the issue,we proposed Replication Strategy with a comprehensive Data Center Selection Method(RS-DCSM),which can determine the appropriate data center to place replicas by considering three key factors:Popularity,space availability,and centrality.The proposed RS-DCSM was simulated using CloudSim and the results proved that data movement between data centers is significantly reduced by 14%reduction in overall replication frequency and 20%decrement in network usage,which outperformed the current replication strategy,known as Dynamic Popularity aware Replication Strategy(DPRS)algorithm. 展开更多
关键词 Cloud computing data replication replica placement data center merits replication algorithm
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Comparison of the replication and neutralization of different SARS-CoV-2 Omicron subvariants in vitro
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作者 Yaqing Zhang Qi Lv +6 位作者 Feifei Qi Fengdi Li Ran Deng Xujian Liang Mingya Liu Yiwei Yan Linlin Bao 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第1期51-56,共6页
Background:New Omicron subvariants are emerging rapidly from BA.1 to BA.4 and BA.5.Their pathogenicity has changed from that of wild-type(WH-09)and Omicron variants have over time become globally dominant.The spike pr... Background:New Omicron subvariants are emerging rapidly from BA.1 to BA.4 and BA.5.Their pathogenicity has changed from that of wild-type(WH-09)and Omicron variants have over time become globally dominant.The spike proteins of BA.4 and BA.5 that serve as the target for vaccine-induced neutralizing antibodies have also changed compared to the previous subvariants,which is likely to cause immune es-cape and the reduction of the protective effect of the vaccine.Our study addresses the above issues and provides a basis for formulating relevant prevention and control strategies.Methods:We collected cellular supernatant and cell lysates and measured the viral titers,viral RNA loads,and E subgenomic RNA(E sgRNA)loads in different Omicron subvariants grown in Vero E6 cells,using WH-09 and Delta variants as a reference.Additionally,we evaluated the in vitro neutralizing activity of different Omicron sub-variants and compared it to the WH-09 and Delta variants using macaque sera with different types of immunity.Results:As the SARS-CoV-2 evolved into Omicron BA.1,the replication ability in vitro began to decrease.Then with the emergence of new subvariants,the replication ability gradually recovered and became stable in the BA.4 and BA.5 subvariants.In WH-09-inactivated vaccine sera,geometric mean titers of neutralization antibodies against different Omicron subvariants declined by 3.7~15.4-fold compared to those against WH-09.In Delta-inactivated vaccine sera,geometric mean titers of neutrali-zation antibodies against Omicron subvariants declined by 3.1~7.4-fold compared to those against Delta.Conclusion:According to the findings of this research,the replication efficiency of all Omicron subvariants declined compared with WH-09 and Delta variants,and was lower in BA.1 than in other Omicron subvariants.After two doses of inactivated(WH-09 or Delta)vaccine,cross-neutralizing activities against various Omicron subvariants were seen despite a decline in neutralizing titers. 展开更多
关键词 cross-neutralize Omicron replication SARS-CoV-2
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Graph-Based Replication and Two Factor Authentication in Cloud Computing
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作者 S.Lavanya N.M.Saravanakumar 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2869-2883,共15页
Many cutting-edge methods are now possible in real-time commercial settings and are growing in popularity on cloud platforms.By incorporating new,cutting-edge technologies to a larger extent without using more infrast... Many cutting-edge methods are now possible in real-time commercial settings and are growing in popularity on cloud platforms.By incorporating new,cutting-edge technologies to a larger extent without using more infrastructures,the information technology platform is anticipating a completely new level of devel-opment.The following concepts are proposed in this research paper:1)A reliable authentication method Data replication that is optimised;graph-based data encryp-tion and packing colouring in Redundant Array of Independent Disks(RAID)sto-rage.At the data centre,data is encrypted using crypto keys called Key Streams.These keys are produced using the packing colouring method in the web graph’s jump graph.In order to achieve space efficiency,the replication is carried out on optimised many servers employing packing colours.It would be thought that more connections would provide better authentication.This study provides an innovative architecture with robust security,enhanced authentication,and low cost. 展开更多
关键词 Graph-based encryption replication ENCRYPTION packing coloring jump graph web graph stream cipher key stream
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A Broker-Based Task-Scheduling Mechanism Using Replication Approach for Cloud Systems
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作者 Abdulelah Alwabel 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2217-2232,共16页
The reliability and availability of cloud systems have become major concerns of service providers,brokers,and end-users.Therefore,studying fault-tolerance mechanisms in cloud computing attracts intense attention in in... The reliability and availability of cloud systems have become major concerns of service providers,brokers,and end-users.Therefore,studying fault-tolerance mechanisms in cloud computing attracts intense attention in industry and academia.The task-scheduling mechanisms can improve the fault-tolerance level of cloud systems.A task-scheduling mechanism distributes tasks to a group of instances to be executed.Much work has been undertaken in this direction to improve the overall outcome of cloud computing,such as improving service qual-ity and reducing power consumption.However,little work on task scheduling has studied the problem of lost tasks from the broker’s perspective.Task loss can hap-pen due to virtual machine failures,server crashes,connection interruption,etc.The broker-based concept means that the backup task can be allocated by the bro-ker on the same cloud service provider(CSP)or a different CSP to reduce costs,for example.This paper proposes a novel fault-tolerant mechanism that employs the primary backup(PB)model of task scheduling to address this issue.The pro-posed mechanism minimizes the impact of failure events by reducing the number of lost tasks.The mechanism is further improved to shorten the makespan time of submitted tasks in cloud systems.The experiments demonstrated that the pro-posed mechanism decreased the number of lost tasks by about 13%–15%com-pared with other mechanisms in the literature. 展开更多
关键词 Cloud computing task scheduling fault tolerance replication broker-based
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Efficient Heuristic Replication Techniques for High Data Availability in Cloud
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作者 H.L.Chandrakala R.Loganathan 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期3151-3164,共14页
Most social networks allow connections amongst many people based on shared interests.Social networks have to offer shared data like videos,photos with minimum latency to the group,which could be challenging as the sto... Most social networks allow connections amongst many people based on shared interests.Social networks have to offer shared data like videos,photos with minimum latency to the group,which could be challenging as the storage cost has to be minimized and hence entire data replication is not a solution.The replication of data across a network of read-intensive can potentially lead to increased savings in cost and energy and reduce the end-user’s response time.Though simple and adaptive replication strategies exist,the solution is non-deter-ministic;the replicas of the data need to be optimized to the data usability,perfor-mance,and stability of the application systems.To resolve the non-deterministic issue of replication,metaheuristics are applied.In this work,Harmony Search and Tabu Search algorithms are used optimizing the replication process.A novel Har-mony-Tabu search is proposed for effective placement and replication of data.Experiments on large datasets show the effectiveness of the proposed technique.It is seen that the bandwidth saving for proposed harmony-Tabu replication per-forms better in the range of 3.57%to 18.18%for varying number of cloud data-centers when compared to simple replication,Tabu replication and Harmony replication algorithm. 展开更多
关键词 Cloud computing data replication bandwidth saving Tabu search Harmony search hybrid Harmony-Tabu search
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人工智能生成内容赋能图书馆知识服务的路径研究 被引量:1
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作者 储节旺 罗怡帆 《情报理论与实践》 CSSCI 北大核心 2024年第8期34-42,共9页
[目的/意义]AIGC拥有强大的内容生成能力,对知识服务领域具有变革作用。研究AIGC赋能图书馆知识服务的路径,对提高图书馆知识服务的效率、提升图书馆在知识服务中的地位具有重要意义。[方法/过程]以模因复制与传播为研究视角,从AIGC拓... [目的/意义]AIGC拥有强大的内容生成能力,对知识服务领域具有变革作用。研究AIGC赋能图书馆知识服务的路径,对提高图书馆知识服务的效率、提升图书馆在知识服务中的地位具有重要意义。[方法/过程]以模因复制与传播为研究视角,从AIGC拓展图书馆知识服务的要素、参与知识服务的过程、提升知识服务的框架三方面,分析AIGC赋能图书馆知识服务的路径,并提出相应建议。[结果/结论]图书馆知识服务的本质是模因的复制与传播;在AIGC的影响下,图书馆知识服务的参与主体由图书馆、AIGC和用户组成;AIGC能有效融入图书馆知识服务的每一个阶段;图书馆应从战略决策、战术筹备和流程设计三部分做出调整。 展开更多
关键词 图书馆知识服务 人工智能生成内容 知识模因 模因复制与传播
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教育定量研究范式:价值、困境与创新路径
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作者 王攀峰 王亚荣 翟静丽 《大学教育科学》 CSSCI 北大核心 2024年第2期50-58,共9页
教育定量研究范式是以实证主义为基础,运用数学工具或统计分析等手段对教育现象或教育过程进行测量,依据数据资料检验理论假设,揭示教育现象中各种因素相关关系的研究范式。它是提升教育研究科学化的关键,是引领教育高质量发展的工具,... 教育定量研究范式是以实证主义为基础,运用数学工具或统计分析等手段对教育现象或教育过程进行测量,依据数据资料检验理论假设,揭示教育现象中各种因素相关关系的研究范式。它是提升教育研究科学化的关键,是引领教育高质量发展的工具,也是适应教育数字化转型需要的必然趋势。但是,当前教育定量研究在推动教育学走向科学化与实证化的过程中面临着多重困境,表现为方法的“内生性”问题、量化的“前提性”问题和研究的“规范性”问题。我国教育研究向实证研究范式的转型、信息技术的迅猛发展、数据共享与公开机制的形成,为定量研究范式创新提供了现实可能。未来,教育定量研究范式应在多种维度上进行变革和创新,推行复制性研究,发展计算教育学,加强教育预测研究。 展开更多
关键词 定量研究范式 复制性研究 计算教育学 教育预测研究
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电液振动台加速度时域波形自适应控制策略
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作者 汤裕 朱真才 +2 位作者 沈刚 刘韩 凌疆语 《振动.测试与诊断》 EI CSCD 北大核心 2024年第3期456-465,616,共11页
针对电液振动台加速度时域波形复现精度低的问题,提出了一种基于内环前馈逆补偿和外环非线性滤波的在线自适应控制策略。首先,构建了电液振动台伺服驱动机构模型,采用三状态控制策略获得了初步加速度控制性能;其次,基于多新息遗忘梯度... 针对电液振动台加速度时域波形复现精度低的问题,提出了一种基于内环前馈逆补偿和外环非线性滤波的在线自适应控制策略。首先,构建了电液振动台伺服驱动机构模型,采用三状态控制策略获得了初步加速度控制性能;其次,基于多新息遗忘梯度算法辨识了三状态控制下系统参数化模型,利用零幅值跟踪技术构建了内环前馈逆补偿策略,拓展了系统频宽,降低了相位滞后误差;然后,引入了外环非线性Volterra自适应滤波算法,抑制了电液振动台模型参数偏差、非线性动态特性和不确定性扰动的影响;最后,在搭建的水平单轴电液振动台上开展了时域波形复现对比实验。结果表明,提出的自适应控制策略与传统策略相比具有更优越的加速度时域波形复现精度。 展开更多
关键词 电液振动台 三状态控制 前馈逆控制 自适应控制 波形复现
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基于演化博弈的车辆换道研究
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作者 黄开启 瞿桃欢 +1 位作者 黄明禹 陈荣华 《公路交通科技》 CAS CSCD 北大核心 2024年第8期31-39,共9页
车辆换道时可能存在与其他车辆发生行驶目的冲突问题,传统的方法没有考虑到车辆之间的动态博弈。为此,根据城市交通的特点以及车辆换道要考虑的各种因素,采用演化博弈的方法进行车辆换道情况分析,为车辆的行驶决策提供方案。首先利用车... 车辆换道时可能存在与其他车辆发生行驶目的冲突问题,传统的方法没有考虑到车辆之间的动态博弈。为此,根据城市交通的特点以及车辆换道要考虑的各种因素,采用演化博弈的方法进行车辆换道情况分析,为车辆的行驶决策提供方案。首先利用车辆在换道时要考虑的时间损失、冲突损失、互让损失、通过收益和换道成本等因素,来构建换道车辆与所要博弈车辆的博弈矩阵,利用博弈矩阵建立车辆冲突的动力学模型,在换道车辆和所要博弈车辆都基于自身利益最大化条件下对存在的各种情况的均衡点的存在和稳定性进行分析,并对演化情况的实际状况进行说明。然后用MATLAB进行仿真验证。在不同情况下,影响车辆进行占道的主导因素也不尽相同,对影响车辆行驶结果的时间损失、冲突损失、互让损失之间的关系进行灵敏度分析。结果表明:车辆在经过博弈后演化的结果可能为采取换道冲突、采取换道不冲突、不采取换道冲突、不采取换道不冲突;发现车辆的互让损失、时间损失会促使车辆进行占道,换道成本和冲突损失会抑制车辆的占道行为。该结果解释了城市交通中存在交通冲突的原因,为车辆驾驶员行驶决策和缓解交通拥堵提供了参考。 展开更多
关键词 智能交通 换道分析 演化博弈 车辆换道 复制者动态方程
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社会主义市场经济的本质特征及其普适性前景
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作者 李松龄 《兰州学刊》 CSSCI 2024年第6期26-37,共12页
社会主义的本质特征是推进全体人民共同富裕,市场经济是发展生产力的工具或手段。因而社会主义市场经济的本质特征是以市场经济发展生产力的方式,推进全体人民共同富裕。市场经济运用资本将新方法新技术应用于生产,促进生产力的发展和... 社会主义的本质特征是推进全体人民共同富裕,市场经济是发展生产力的工具或手段。因而社会主义市场经济的本质特征是以市场经济发展生产力的方式,推进全体人民共同富裕。市场经济运用资本将新方法新技术应用于生产,促进生产力的发展和财富增长,能为全体人民共同富裕提供财富支持,与社会主义的本质特征相统一。资本占有劳动生产的剩余价值,不利于缩小收入差距和推进全体人民共同富裕,与社会主义的本质特征相矛盾。社会主义与市场经济是对立统一的矛盾的两个方面。社会主义市场经济制度变革,选择生产资料资本化为资本所有者股份和劳动力资本化为劳动者股份相结合的新型股份制作为改革目标,有利于化解社会主义和市场经济的矛盾。社会主义市场经济具有普适价值和可复制性。 展开更多
关键词 社会主义市场经济 本质特征 普适价值 可复制性
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具NK细胞的溶瘤病毒疗法的模型分析
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作者 赵艳 邱志鹏 邓齐 《鲁东大学学报(自然科学版)》 2024年第1期66-75,共10页
本文建立了一类包含自然杀伤细胞(NK细胞)免疫反应的肿瘤病毒相互作用模型。首先分析了系统的边界性态,将系统的平衡点进行完整的分类,讨论了边界平衡点的局部稳定性,并从数值上验证了周期解的存在性,最后讨论了NK细胞在病毒治疗中所起... 本文建立了一类包含自然杀伤细胞(NK细胞)免疫反应的肿瘤病毒相互作用模型。首先分析了系统的边界性态,将系统的平衡点进行完整的分类,讨论了边界平衡点的局部稳定性,并从数值上验证了周期解的存在性,最后讨论了NK细胞在病毒治疗中所起到的作用。数值结果表明:a)整体肿瘤大小与病毒感染率成反比,与肿瘤生长速率成正比;b)对于NK细胞相关参数,NK细胞从淋巴结的流入速率越大,最终肿瘤越小;若产生NK细胞增殖,当增殖速率比较小时,相较于无NK增殖时,最终肿瘤变大,即较小的NK细胞增殖对治疗产生负面的影响,但当NK细胞的增殖速率过高时,将会导致肿瘤和病毒的完全清除。 展开更多
关键词 溶瘤病毒 自然杀伤细胞 数学模型 病毒复制
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基于CNN-LSTM和卷复制方法的高可用系统设计方法
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作者 张焱 李新建 +4 位作者 王畅 章建军 陈小虎 邹鑫灏 严智 《南京邮电大学学报(自然科学版)》 北大核心 2024年第4期114-121,共8页
针对单机服务器存在的单点故障问题,以及主备双机中存在的逻辑故障导致数据丢失的问题,设计了一种基于卷积和长短期记忆神经网络(CNN-LSTM)和卷复制方法的HA(High Availability)系统。系统至少包含两个节点,一个主节点以及一个或多个备... 针对单机服务器存在的单点故障问题,以及主备双机中存在的逻辑故障导致数据丢失的问题,设计了一种基于卷积和长短期记忆神经网络(CNN-LSTM)和卷复制方法的HA(High Availability)系统。系统至少包含两个节点,一个主节点以及一个或多个备用节点,主节点和备节点之间支持主备切换。每个服务器节点上包含4个模块,分别是负责接收配置信息与读写请求的代理模块;进行磁盘读写操作和重定向读写的磁盘I/O(输入输出)模块;负责主备节点间备份快照、映射表、数据块复制的卷复制模块以及基于CNN-LSTM进行状态检测的高可用模块。实验表明,该系统不仅可以解决单点故障问题,也可以解决主备双机集群中无法解决的逻辑错误问题;同时基于CNN-LSTM方法,自动针对服务器的运行健康状态进行分析和预测,可以根据预测结果自动通知管理员进行处理或自动进行主备切换。 展开更多
关键词 卷复制 数据丢失 快照 CNN-LSTM 高可用系统
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连续振动载荷在线复现控制技术研究
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作者 严侠 王军评 +1 位作者 毛勇建 邓婷 《振动工程学报》 EI CSCD 北大核心 2024年第10期1679-1687,共9页
提出一种主从分布式振动试验方法,建立了连续振动载荷在线复现控制技术,研制了系统样机。其中,提出一种信号分帧处理与重构技术,解决了长时连续振动载荷的在线波形复现难题;提出一种基于多量级样本库构建与加权平均的传递函数动态估计方... 提出一种主从分布式振动试验方法,建立了连续振动载荷在线复现控制技术,研制了系统样机。其中,提出一种信号分帧处理与重构技术,解决了长时连续振动载荷的在线波形复现难题;提出一种基于多量级样本库构建与加权平均的传递函数动态估计方法,抑制了系统非线性对控制精度的影响;采用谱误差反馈修正方法,改善了系统的频域控制精度。开展了“1主2从”联台试验,结果表明:时域和频域控制精度良好,整体延迟时间在亚秒量级,全程总均方根值误差在1%以内,为主从分布式振动试验提供了关键技术支撑。 展开更多
关键词 主从分布式振动试验 振动控制 在线波形复现 传递函数 分帧与重构 多量级随机信号驱动
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猪急性腹泻综合征冠状病毒诱导细胞自噬并增强病毒复制的研究 被引量:3
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作者 曾苗苗 刘大凯 +8 位作者 张记宇 张燎原 冯廷帅 杨小曼 时洪艳 张鑫 陈建飞 石达 冯力 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第1期61-69,共9页
为研究猪急性腹泻综合征冠状病毒(SADS-CoV)感染细胞是否诱导自噬及自噬对病毒复制的影响,本研究将SADS-CoV(MOI 0.1)接种Vero E6细胞培养36 h后,经透射电子显微镜观察可见,SADS-CoV感染的细胞中出现了包裹胞浆的自噬体样双层膜结构,证... 为研究猪急性腹泻综合征冠状病毒(SADS-CoV)感染细胞是否诱导自噬及自噬对病毒复制的影响,本研究将SADS-CoV(MOI 0.1)接种Vero E6细胞培养36 h后,经透射电子显微镜观察可见,SADS-CoV感染的细胞中出现了包裹胞浆的自噬体样双层膜结构,证实SADS-CoV可以诱导Vero E6细胞发生自噬。构建pEGFP-LC3的真核表达质粒并经双酶切及测序鉴定正确后转染Vero E6细胞,24 h后以SADS-CoV感染,24 h后经激光共聚焦显微镜观察可见,与阴性对照组细胞相比,感染SADS-CoV的细胞出现绿色荧光的点状聚集。进一步将SADS-CoV(MOI 0.1)感染Vero E6细胞不同时间后通过western blot检测自噬相关蛋白LC3-Ⅱ和p62表达水平的变化,结果显示,与阴性对照组相比,SADS-CoV感染组LC3-Ⅱ的表达水平升高,LC3-Ⅱ/GAPDH比值呈上升趋势,而p62蛋白表达水平则显著降低(P<0.05),表明SADS-CoV感染能够诱导Vero E6细胞产生完整的自噬应答。为了探究自噬对病毒复制的影响,本研究分别采用自噬抑制剂3-MA和自噬诱导剂Rapamycin处理Vero E6细胞后以SADS-CoV感染,于感染后不同时间收获细胞,通过western blot和病毒滴度(TCID_(50))测定检测SADS-CoV N蛋白表达水平的变化。结果显示,与仅感染病毒的对照组相比,采用3-MA处理Vero E6细胞后SADS-CoV N蛋白的表达水平及TCID_(50)均显著降低(P<0.05),而采用Rapamycin处理后SADS-CoV N蛋白的表达水平及TCID_(50)则均显著升高(P<0.05)。针对ATG5基因设计3条特异性的ATG5 si RNA(siATG5-1/2/3),将干扰效率较好的siATG5-1转染Vero E6细胞后再以SADS-CoV感染,24 h后检测病毒滴度并利用western blot检测SADS-CoV N蛋白表达水平的变化。结果显示,与未转染siATG5的3组阴性细胞相比,转染细胞中SADS-CoV N蛋白的表达水平及病毒滴度均显著降低(P<0.05)。本研究首次表明SADS-CoV感染可以诱导宿主细胞自噬并促进病毒的复制,该结果为深入研究SADS-CoV感染与其致病机理以及防控该病毒的感染奠定了基础。 展开更多
关键词 猪急性腹泻综合征冠状病毒 自噬 病毒复制 LC3-Ⅱ
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2017—2023年我国历史教材研究热点的回顾与前瞻——基于人大复印报刊资料的分析
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作者 李洁 《天津师范大学学报(基础教育版)》 CSSCI 北大核心 2024年第4期71-75,共5页
通过对2017-2023年《复印报刊资料·中学历史、地理教与学》全文转载的历史教材论文进行整理和分析,发现我国历史教材研究热点主要有重大主题教育在历史教材中的体现、历史教材的结构分析、统编初中历史教材的编写与使用、统编高中... 通过对2017-2023年《复印报刊资料·中学历史、地理教与学》全文转载的历史教材论文进行整理和分析,发现我国历史教材研究热点主要有重大主题教育在历史教材中的体现、历史教材的结构分析、统编初中历史教材的编写与使用、统编高中历史教材的编写与使用、国外历史教材等。基于研究现状,建议未来历史教材的研究加强以下五方面的探讨:重大主题教育进历史教材的深入研究、历史教材的习题研究、历史教材的评价研究、新版统编初中历史教材研究、历史教材使用的实证研究。 展开更多
关键词 人大复印资料 历史教材 研究热点
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中学历史教育研究2023年度报告——基于2023年《复印报刊资料·中学历史、地理教与学》转载历史教育论文的分析
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作者 徐赐成 沈琰琰 《天津师范大学学报(基础教育版)》 CSSCI 北大核心 2024年第2期1-6,共6页
2023年度《复印报刊资料·中学历史、地理教与学》转载发表的中学历史教育类成果,集中反映了年度研究基本概况:历史课程功能研究具体化、历史教学理论研究实践化、历史教学改革研究综合化、历史教科书及其运用研究融通化、历史学科... 2023年度《复印报刊资料·中学历史、地理教与学》转载发表的中学历史教育类成果,集中反映了年度研究基本概况:历史课程功能研究具体化、历史教学理论研究实践化、历史教学改革研究综合化、历史教科书及其运用研究融通化、历史学科试题及命制研究素养化、历史课程核心素养研究过程化、历史教育国际比较研究价值化、历史教师职业素养研究需要强化。面对未来挑战,历史教育理论、课程改革、历史学习、教师教育研究需要深化。 展开更多
关键词 人大复印报刊资料 中学历史教育研究 年度报告 综合研究
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细胞周期蛋白激酶抑制调控蛋白p21在HHV-8病毒裂解复制周期的作用
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作者 张庆 秦苏萍 +3 位作者 李小翠 王晓天 刘晓梅 周峰 《徐州医科大学学报》 CAS 2024年第2期95-99,共5页
目的研究细胞周期蛋白激酶抑制调控蛋白p21对人类疱疹病毒8型(human herpesvirus 8,HHV-8)病毒裂解复制周期的影响。方法组蛋白去乙酰化酶(histone deacetylase,HDAC)抑制剂SAHA预处理后,倒置荧光显微镜观察红色荧光蛋白(RFP)阳性的iSLK... 目的研究细胞周期蛋白激酶抑制调控蛋白p21对人类疱疹病毒8型(human herpesvirus 8,HHV-8)病毒裂解复制周期的影响。方法组蛋白去乙酰化酶(histone deacetylase,HDAC)抑制剂SAHA预处理后,倒置荧光显微镜观察红色荧光蛋白(RFP)阳性的iSLK.219细胞数,实时定量PCR检测TREx-K-Rta BCBL-1细胞中HHV-8病毒相关基因的mRNA水平。脂质体转染p21-siRNA后,免疫印迹法检测iSLK.219和TREx-K-Rta BCBL-1细胞中p21蛋白表达,计算RFP阳性iSLK.219细胞百分率,检测TREx-K-Rta BCBL-1细胞中ORF50和PAN的mRNA水平,CCK-8法和台盼蓝染色观察细胞存活情况。结果SAHA显著增强iSLK.219细胞RFP阳性率、TREx-K-Rta BCBL-1细胞中HHV-8裂解复制周期相关基因ORF50、PAN及K8.1的mRNA水平和p21蛋白表达,差异有统计学意义(P<0.05)。siRNA沉默p21后,iSLK.219细胞RFP阳性率、TREx-K-Rta BCBL-1细胞中HHV-8裂解复制周期相关基因ORF50和PAN mRNA水平显著下降,差异有统计学意义(P<0.05),且保护SAHA介导的TREx-K-Rta BCBL-1细胞死亡。结论抑制HDAC活性通过调控p21促进HHV-8病毒裂解复制。 展开更多
关键词 人类疱疹病毒8型 病毒裂解复制周期 组蛋白去乙酰化酶 细胞周期蛋白激酶抑制调控蛋白p21 细胞死亡
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