期刊文献+
共找到31,432篇文章
< 1 2 250 >
每页显示 20 50 100
Effect of Brisk Walking on Self-Care Agency or Care Dependency among Colorectal Cancer Patients with Permanent Stoma
1
作者 Zhen Zhang Anabella G.Javier 《Journal of Clinical and Nursing Research》 2024年第5期68-82,共15页
Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study ... Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency. 展开更多
关键词 Permanent stoma Colorectal cancer Brisk walking Self-care agency Care dependency
下载PDF
NGDcrm:a numeric graph dependency-based conflict resolution method for knowledge graph 被引量:1
2
作者 马江涛 Wang Yanjun +1 位作者 Chen Xueting Qiao Yaqiong 《High Technology Letters》 EI CAS 2021年第2期153-162,共10页
Knowledge graph(KG)conflict resolution is to solve knowledge conflicts problem in the construction of KG.Aiming at the problem of KG conflict resolution,a KG conflict resolution algorithm NGDcrm is proposed,which is a... Knowledge graph(KG)conflict resolution is to solve knowledge conflicts problem in the construction of KG.Aiming at the problem of KG conflict resolution,a KG conflict resolution algorithm NGDcrm is proposed,which is a numeric graph dependency-based conflict resolution method.NGDcrm utilizes the dependency graph to perform arithmetic calculation and predicate comparison of numerical entity knowledge in the KG.NGDcrm first uses a parallel segmentation method to segment the KG;then,it extracts the features of the KG according to KG embedding;finally,it uses numerical graph dependencies to detect and correct the wrong facts in the KG based on the extracted features.The experimental results on real data show that NGDcrm is better than the state-of-the-art knowledge conflict resolution method.Among them,the AUC value of NGDcrm on the DBpedia dataset is 15.4%higher than the state-of-the-art method. 展开更多
关键词 dependency graph knowledge conflict resolution knowledge graph(KG) numeric graph dependency(ngd)
下载PDF
Escaping Dependency and Trade War:China and the US
3
作者 Chen Ziye Li Bin 《China Economist》 2023年第1期36-44,共9页
Marxist political economy provides a perspective for grasping the root cause of the China-US trade war.The international relations of production,which stem from the international division of labor,shape the distributi... Marxist political economy provides a perspective for grasping the root cause of the China-US trade war.The international relations of production,which stem from the international division of labor,shape the distribution of international economic interests and the political status of countries.Traditionally,developing countries have been subjected to the“periphery”in the international division of labor.In the new global value chain,developing countries have remained in a subordinate position characterized by“technological-market”dependence.To achieve the goal of building a strong modern nation,China must escape the“technological-market”dependence.Yet China’s efforts and achievements in escaping dependent development are deemed as a threat to US vested interests in the international markets.To preserve the economic foundation of its hegemony,the US has resorted to a trade war to contain China’s development. 展开更多
关键词 dependency theory dependent development global value CHAINS “technological-market” dependence China-US TRADE WAR
下载PDF
Reliability modeling of mutual DCFP considering failure physical dependency
4
作者 CHEN Ying YANG Tianyu WANG Yanfang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1063-1073,共11页
Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has bee... Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has been widely studied.Electronic system may experience mutual effects of degradation and shocks,they are considered to be interdependent.Both the degradation and the shock processes will decrease the limit of system and cause cumulative effect.Finally,the competition of hard and soft failure will cause the system failure.Based on the failure mechanism accumulation theory,this paper constructs the shock-degradation acceleration and the threshold descent model,and a system reliability model established by using these two models.The mutually DCFP effect of electronic system interaction has been decomposed into physical correlation of failure,including acceleration,accumulation and competition.As a case,a reliability of electronic system in aeronautical system has been analyzed with the proposed method.The method proposed is based on failure physical evaluation,and could provide important reference for quantitative evaluation and design improvement of the newly designed system in case of data deficiency. 展开更多
关键词 electronic system dependent competing failure process(DCFP) failure physical dependency threshold descent model competition failure modes
下载PDF
Quality Control at Nomophobia and Dependency to Technological
5
作者 Pearlyne Willie Wong Huay Woon You 《International Journal of Mental Health Promotion》 2023年第8期891-901,共11页
This study aims to investigate the phenomenon of technological gadget usage among pre-university students,which include the time spent using them,as well as their purpose and influence.A descriptive research design was... This study aims to investigate the phenomenon of technological gadget usage among pre-university students,which include the time spent using them,as well as their purpose and influence.A descriptive research design was adopted in this study.131 pre-university students were randomly selected to answer a structured questionnaire.They were informed two weeks earlier to keep track on their time spent on technological devices,before answering the questionnaire.Findings showed that 99.2%of the respondents owned at least two technological gadgets,and all respondents own a smartphone.The main two gadgets that respondents spend at least 4 h a day on are smartphones(65.6%)and computers/laptops(21.4%).This indicates that smartphones are commonly used and owned among the respondents.The majority of the respondents are moderately nomophobia and moderately dependent on smartphones(70.2%and 66.4%,respectively).Correlation analysis demonstrates that the total time spent on gadgets in a day has a significant positive correlation with gadget dependency and total number of gadgets owned.Meanwhile,logistic regression was conducted to estimate the probability of nomophobia and dependency using total time spent and total number of technological gadgets.From thefindings,it was demonstrated that when the total time spent on using technological gadgets increasing,there is greater probability that the respondents develop nomophobia and dependency.This indicates that nomophobia and dependency to technological gadgets can be used to predict lifestyle profiles.The use of technological gadgets can bring both benefit and harm to its user.In light of this,user has to remain rational in order to derive maximum benefit from it. 展开更多
关键词 Nomophobia dependency technological gadgets pre-university students quality control
下载PDF
Read-Write Dependency Aware Register Allocation
6
作者 Sheng Xiao Yong Chen +1 位作者 Jing He Xi Yang 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3527-3540,共14页
Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by th... Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by the read-write dependency,bottlenecks the voltage down-scaling and so the energy efficiency of TS processors.We proposed a method called Read-Write Dependency Aware Register Allocation.It is based on the Read-Write Dependency aware Interference Graph(RWDIG)conception.Registers are reallocated to loosen the read-write dependencies,so resulting in a reduction of timing errors.The traditional no operation(Nop)padding method is also redesigned to increase the distance value to above 2.We analyzed the dependencies of registers and maximized the average distance value of read and write dependencies.Experimental results showed that we can reduce all read-write dependency by Nop padding,as well as the overhead timing errors.An energy saving of approximately 7%was achieved. 展开更多
关键词 Read-write dependency timing speculative energy efficiency
下载PDF
Analyzing Ethereum Smart Contract Vulnerabilities at Scale Based on Inter-Contract Dependency
7
作者 Qiuyun Lyu Chenhao Ma +3 位作者 Yanzhao Shen Shaopeng Jiao Yipeng Sun Liqin Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1625-1647,共23页
Smart contracts running on public blockchains are permissionless and decentralized,attracting both developers and malicious participants.Ethereum,the world’s largest decentralized application platform on which more t... Smart contracts running on public blockchains are permissionless and decentralized,attracting both developers and malicious participants.Ethereum,the world’s largest decentralized application platform on which more than 40 million smart contracts are running,is frequently challenged by smart contract vulnerabilities.What’s worse,since the homogeneity of a wide range of smart contracts and the increase in inter-contract dependencies,a vulnerability in a certain smart contract could affect a large number of other contracts in Ethereum.However,little is known about how vulnerable contracts affect other on-chain contracts and which contracts can be affected.Thus,we first present the contract dependency graph(CDG)to perform a vulnerability analysis for Ethereum smart contracts,where CDG characterizes inter-contract dependencies formed by DELEGATECALL-type internal transaction in Ethereum.Then,three generic definitions of security violations against CDG are given for finding respective potential victim contracts affected by different types of vulnerable contracts.Further,we construct the CDG with 195,247 smart contracts active in the latest blocks of the Ethereum and verify the above security violations against CDG by detecting three representative known vulnerabilities.Compared to previous large-scale vulnerability analysis,our analysis scheme marks potential victim contracts that can be affected by different types of vulnerable contracts,and identify their possible risks based on the type of security violation actually occurring.The analysis results show that the proportion of potential victim contracts reaches 14.7%,far more than that of corresponding vulnerable contracts(less than 0.02%)in CDG. 展开更多
关键词 Smart contract vulnerability smart contract homogeneity contract dependency graph automated analysis
下载PDF
Percolation transitions in edge-coupled interdependent networks with directed dependency links
8
作者 高彦丽 于海波 +2 位作者 周杰 周银座 陈世明 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期586-595,共10页
We propose a model of edge-coupled interdependent networks with directed dependency links(EINDDLs)and develop the theoretical analysis framework of this model based on the self-consistent probabilities method.The phas... We propose a model of edge-coupled interdependent networks with directed dependency links(EINDDLs)and develop the theoretical analysis framework of this model based on the self-consistent probabilities method.The phase transition behaviors and parameter thresholds of this model under random attacks are analyzed theoretically on both random regular(RR)networks and Erd¨os-Renyi(ER)networks,and computer simulations are performed to verify the results.In this EINDDL model,a fractionβof connectivity links within network B depends on network A and a fraction(1-β)of connectivity links within network A depends on network B.It is found that randomly removing a fraction(1-p)of connectivity links in network A at the initial state,network A exhibits different types of phase transitions(first order,second order and hybrid).Network B is rarely affected by cascading failure whenβis small,and network B will gradually converge from the first-order to the second-order phase transition asβincreases.We present the critical values ofβfor the phase change process of networks A and B,and give the critical values of p andβfor network B at the critical point of collapse.Furthermore,a cascading prevention strategy is proposed.The findings are of great significance for understanding the robustness of EINDDLs. 展开更多
关键词 edge-coupled interdependent networks with directed dependency links percolation transitions cascading failures robustness analysis
下载PDF
多重连接探针扩增技术在食品安全检测中的应用研究进展 被引量:2
9
作者 石长波 梁昌谋 +2 位作者 王鹏宇 姜承泽 赵钜阳 《粮食与油脂》 北大核心 2024年第3期4-7,共4页
阐述了多重连接探针扩增(MLPA)技术在食品过敏原检测、食品掺假、食源性致病菌和转基因食品检测中的应用现状,并对该技术在食品安全检测领域的发展趋势和挑战进行展望。
关键词 多重连接探针扩增技术 过敏原 食源性病原菌 食品安全
下载PDF
miR-567通过调控CDK8在NSCLC增殖、迁移和细胞周期中的作用及其临床相关性研究 被引量:1
10
作者 李海洋 赵振山 +4 位作者 李静 戎瑶 郑爱民 郝孟辉 田发明 《国际检验医学杂志》 CAS 2024年第3期335-340,346,共7页
目的探讨微小RNA(miR)-567通过调控周期蛋白依赖性激酶8(CDK8)在非小细胞肺癌(NSCLC)增殖、迁移和细胞周期中的作用及其临床相关性研究。方法收集40例NSCLC患者的肿瘤组织和临近癌旁组织,采用实时荧光定量PCR(qRT-PCR)检测miR-567和CDK... 目的探讨微小RNA(miR)-567通过调控周期蛋白依赖性激酶8(CDK8)在非小细胞肺癌(NSCLC)增殖、迁移和细胞周期中的作用及其临床相关性研究。方法收集40例NSCLC患者的肿瘤组织和临近癌旁组织,采用实时荧光定量PCR(qRT-PCR)检测miR-567和CDK8的表达。将miR-NC mimic、miR-567 mimic、oe-NC和oe-CDK8转染至A549和H1975细胞中,使用qRT-PCR检测miR-567和CDK8的表达,CCK-8法检测细胞增殖水平,Transwell法检测细胞迁移水平,流式细胞术检测细胞周期变化。通过荧光素酶报告基因实验检测miR-567与CDK8的靶向性。结果在NSCLC患者的肿瘤组织中,miR-567表达降低,而CDK8表达升高,二者呈负相关(P<0.05)。在A549和H1975细胞中,miR-567 mimic组相较于miR-NC mimic组,miR-567表达升高,CDK8表达降低,细胞增殖和迁移水平降低,细胞G1期比例升高,S期比例降低;miR-567 mimic组在正常型CDK8中,荧光强度低于miR-NC mimic组;miR-567 mimic+oe-CDK8组相较于miR-567 mimic+oe-NC组,CDK8表达升高,细胞增殖和迁移水平升高,细胞G1期比例降低,S期比例升高。结论miR-567通过靶向抑制CDK8表达,控制肿瘤细胞在S期阻滞,从而抑制NSCLC的增殖和迁移能力。 展开更多
关键词 非小细胞肺癌 细胞周期 细胞周期蛋白依赖性激酶8 微小RNA-567
下载PDF
微服务系统服务依赖发现技术综述
11
作者 张齐勋 吴一凡 +3 位作者 杨勇 贾统 李影 吴中海 《软件学报》 EI CSCD 北大核心 2024年第1期118-135,共18页
微服务架构得到了广泛的部署与应用,提升了软件系统开发的效率,降低了系统更新与维护的成本,提高了系统的可扩展性.但微服务变更频繁、异构融合等特点使得微服务故障频发、其故障传播快且影响大,同时微服务间复杂的调用依赖关系或逻辑... 微服务架构得到了广泛的部署与应用,提升了软件系统开发的效率,降低了系统更新与维护的成本,提高了系统的可扩展性.但微服务变更频繁、异构融合等特点使得微服务故障频发、其故障传播快且影响大,同时微服务间复杂的调用依赖关系或逻辑依赖关系又使得其故障难以被及时、准确地定位与诊断,对微服务架构系统的智能运维提出了挑战.服务依赖发现技术从系统运行时数据中识别并推断服务之间的调用依赖关系或逻辑依赖关系,构建服务依赖关系图,有助于在系统运行时及时、精准地发现与定位故障并诊断根因,也有利于如资源调度、变更管理等智能运维需求.首先就微服务系统中服务依赖发现问题进行分析,其次,从基于监控数据、系统日志数据、追踪数据等3类运行时数据的角度总结分析了服务依赖发现技术的技术现状;然后,以基于服务依赖关系图的故障根因定位、资源调度与变更管理等为例,讨论了服务依赖发现技术应用于智能运维的相关研究.最后,对服务依赖发现技术如何准确地发现调用依赖关系和逻辑依赖关系,如何利用服务依赖关系图进行变更治理进行了探讨并对未来的研究方向进行了展望. 展开更多
关键词 服务依赖 故障诊断 微服务
下载PDF
酒依赖患者的腹侧苍白球改变及其与复饮的关系
12
作者 杨清艳 杨可冰 +5 位作者 赵荣江 牛雅娟 于婷 范丰梅 范宏振 谭云龙 《中国心理卫生杂志》 CSCD 北大核心 2024年第4期301-305,共5页
目的:探讨酒依赖患者腹侧苍白球(VP)的体积变化及其与复饮的关系。方法:采用横断面与队列研究相结合的方法,选取符合美国精神障碍诊断与统计手册第4版(DSM-IV)酒精依赖综合征诊断标准的患者33例,在停酒14~28 d内进行头部磁共振成像检查... 目的:探讨酒依赖患者腹侧苍白球(VP)的体积变化及其与复饮的关系。方法:采用横断面与队列研究相结合的方法,选取符合美国精神障碍诊断与统计手册第4版(DSM-IV)酒精依赖综合征诊断标准的患者33例,在停酒14~28 d内进行头部磁共振成像检查,采用自制调查问卷、临床机构酒精戒断症状评定量表(CIWA)、酒精使用障碍筛查量表(AUDIT)进行评估,采用自制随访问卷评估半年内治疗结局。比较酒依赖组与对照组,复饮组与非复饮组间VP体积。结果:酒依赖组的VP体积小于正常对照组[(1749±492)mm^(3) vs.(2116±189)mm^(3),P<0.05],复饮组的VP体积较非复饮组大[(1956±452)mm^(3) vs.(1555±458)mm^(3),P<0.05]。结论:酒依赖患者的VP可能参与病理性奖赏环路功能,并与复饮有关。 展开更多
关键词 酒依赖 复饮 皮质下 腹侧苍白球 磁共振成像
下载PDF
再生粗骨料混凝土应力-应变关系 被引量:1
13
作者 肖建庄 唐宇翔 +1 位作者 张凯建 杨海峰 《工程力学》 EI CSCD 北大核心 2024年第2期43-55,共13页
再生粗骨料混凝土应力-应变关系是实现其材料到结构力学分析的桥梁纽带,成为再生粗骨料混凝土结构基础理论的基石。介绍了作者团队多年来在再生粗骨料混凝土应力-应变关系方面取得的研究进展:采用模型化再生粗骨料方法,研究了复杂界面... 再生粗骨料混凝土应力-应变关系是实现其材料到结构力学分析的桥梁纽带,成为再生粗骨料混凝土结构基础理论的基石。介绍了作者团队多年来在再生粗骨料混凝土应力-应变关系方面取得的研究进展:采用模型化再生粗骨料方法,研究了复杂界面过渡区对再生粗骨料混凝土破坏行为的影响,揭示了再生粗骨料混凝土细观损伤本质与演化机理;从静力作用到动力作用,系统地开展了不同工况下再生粗骨料混凝土应力-应变行为试验研究,探明了载荷条件对再生粗骨料混凝土应力与变形的影响规律并建立了相适应的力学与数学模型;进一步考虑再生粗骨料性能时空变异性,发现了再生粗骨料混凝土力学响应的概率分布特征,提出了再生粗骨料混凝土随机损伤本构关系;基于获得的本构模型,完成了再生粗骨料混凝土构件时变可靠度分析和结构动力非线性分析,为再生粗骨料混凝土在实际工程中的安全应用提供了理论支撑;提炼了相关研究结论并对未来研究工作进行了展望。 展开更多
关键词 再生粗骨料混凝土 应力-应变关系 多工况受力 随机性 时变可靠度 非线性分析
下载PDF
机械通气脓毒症患者肺部超声重力依赖失充气表型与不良预后的相关性
14
作者 王茜 尹万红 +4 位作者 邹同娟 铁馨 朱俊臣 陈侣林 曾学英 《临床荟萃》 CAS 2024年第4期314-319,共6页
目的分析脓毒症机械通气患者不同肺部超声表型的临床特征,探讨肺部超声重力依赖肺失充气表型对脓毒症机械通气患者不良预后的相关性。方法回顾性分析2019年4月至2020年10月四川大学华西医院重症医学科收治的机械通气脓毒症患者155例,按... 目的分析脓毒症机械通气患者不同肺部超声表型的临床特征,探讨肺部超声重力依赖肺失充气表型对脓毒症机械通气患者不良预后的相关性。方法回顾性分析2019年4月至2020年10月四川大学华西医院重症医学科收治的机械通气脓毒症患者155例,按照28 d预后情况分为生存组(n=124)和死亡组(n=31),通过单因素和多因素Cox回顾分析肺部超声重力依赖失充气表型对患者28 d预后结局的影响。绘制Kaplan-Meier曲线分析重力依赖性和非重力依赖失充气表型与28 d预后生存的关系。结果单因素Cox回归分析发现,白细胞介素-6、SOFA评分、机械通气时间(h)、间质性失充气、实变性失充气、不张性失充气、存在重力依赖性失充气改变与患者28 d预后结局相关(P<0.05),进一步通过多因素Cox分析校正后发现存在间质性失充气肺部超声模式、机械通气时间和存在重力依赖性失充气改变与患者不良预后结局相关(P<0.05),重力依赖肺失充气表型的死亡风险是非重力依赖肺失充气表型的的2.003倍(HR=2.003,P=0.028,95%CI=1.112-6.387)。结论重力依赖肺失充气肺部超声表型可作为脓毒症机械通气患者不良预后的预测指标。 展开更多
关键词 脓毒症 肺部超声表型 重力依赖失充气 预后
下载PDF
深空探测自主运行的一种可信性技术体系
15
作者 党炜 骆军委 +8 位作者 郑作环 敖亮 李博 李鹏 熊盛阳 许鹏程 宋恒旭 胡剑桥 冯业为 《空间科学学报》 CAS CSCD 北大核心 2024年第2期228-240,共13页
未认知与不确定性是深空探测任务的基本特征.本文基于战略导向的体系化基础研究,建立了一种面向科学价值最大化的探测场景和以可靠性为核心技术基础的深空探测自主运行可信性技术体系.分析研究了深空探测场景下的可靠性概念;面向精确感... 未认知与不确定性是深空探测任务的基本特征.本文基于战略导向的体系化基础研究,建立了一种面向科学价值最大化的探测场景和以可靠性为核心技术基础的深空探测自主运行可信性技术体系.分析研究了深空探测场景下的可靠性概念;面向精确感知、最优计算、准确决策、快精准执行的目标要素,提出了深空探测自主运行的可信性体系框架以及“需求-认知-工程”总体技术架构;针对自主运行可信性的关键技术难点,开展了可靠性导向的多物理场、强耦合白盒建模,复杂网络故障传播机制分析,COTS元器件深空探测应用的高可靠保证,以及“模型+数据+知识”一体的融合机制分析等研究.对该技术体系的关键技术验证策略及其最小系统在卫星星座中的应用进行了验证,结果表明,所提出的技术体系具有较高的工程价值. 展开更多
关键词 深空探测 自主运行 可靠性 可信性 多物理场 复杂网络
下载PDF
比较蛋白质组学揭示茉莉酸甲酯诱导的雷公藤甲素生物合成
16
作者 张逸风 赵瑜君 +4 位作者 苏平 吴晓毅 夏梦 高伟 黄璐琦 《中国现代中药》 CAS 2024年第2期316-327,共12页
目的:探索雷公藤甲素生物合成途径,以提高其产量或用于合成生物学异源生产。方法:使用无标记(lable-free)比较蛋白质组学对茉莉酸甲酯(MeJA)诱导的雷公藤悬浮细胞进行测序,通过京都基因与基因组百科全书(KEGG)、基因本体(GO)分析等方法... 目的:探索雷公藤甲素生物合成途径,以提高其产量或用于合成生物学异源生产。方法:使用无标记(lable-free)比较蛋白质组学对茉莉酸甲酯(MeJA)诱导的雷公藤悬浮细胞进行测序,通过京都基因与基因组百科全书(KEGG)、基因本体(GO)分析等方法,结合基因转录表达分析和基因体内功能研究,逐步筛选参与雷公藤甲素生物合成的功能基因。结果:MeJA诱导不同时间的样品组鉴定得到376个差异蛋白质,包括8个细胞色素P450酶(CYP450)、3个转录因子(TF)和2-氧戊二酸依赖的双加氧酶(2ODD)。其中CYP71BE89、CYP82AQ2和Tw2ODD基因在MeJA诱导及植物不同组织部位中,均与已知参与雷公藤甲素母核环化的二萜合酶TwTPS7(v2)和TwTPS27(v2)基因具有相似的表达模式,表明其可能与雷公藤甲素生物合成相关。进一步利用植物细胞体内功能研究,验证了CYP71BE89、CYP82AQ2和Tw2ODD基因干扰使雷公藤甲素积累分别降低了24.1%、41.4%和71.4%,表明了3个基因与雷公藤甲素生物合成直接相关。结论:利用比较蛋白质组学技术揭示了几种与雷公藤甲素生物合成相关的蛋白,进一步表征了雷公藤甲素生物合成与外源激素刺激之间的关系,并为发掘中药活性成分生物合成途径提供了一种有效方法。 展开更多
关键词 雷公藤 比较蛋白质组学 雷公藤甲素 细胞色素P450酶 2-氧戊二酸依赖的双加氧酶
下载PDF
京津多机场系统容量损失影响分析
17
作者 韩红蓉 黄婕 赵嶷飞 《科学技术与工程》 北大核心 2024年第12期5212-5219,共8页
全球范围内多机场系统数量和规模都在不断增长。由于终端区内有限资源的限制,邻近机场的运行存在一定的相关性,这导致多机场系统运行效率低下。为了估计多机场运行产生的限制,以北京终端区为例提出一种统计分析框架对多机场系统的容量... 全球范围内多机场系统数量和规模都在不断增长。由于终端区内有限资源的限制,邻近机场的运行存在一定的相关性,这导致多机场系统运行效率低下。为了估计多机场运行产生的限制,以北京终端区为例提出一种统计分析框架对多机场系统的容量损失进行整体分析。首先,根据理论容量模型分别计算出北京终端区各机场的理论容量,并进一步确定各机场独立运行下的实际容量;其次,以北京终端区的历史运行数据为基础,估计出3个机场及终端区系统的具有鲁棒性的Pareto容量包络曲线;最后,基于独立运行容量与相关运行容量量化出终端区各机场及多机场系统的实际容量损失。为进一步提高多机场终端区的运行效率提供建议与参考。 展开更多
关键词 多机场系统 终端区 相关性 容量损失
下载PDF
深部直墙半圆拱巷道围岩时效损伤劣化特征与动态补强技术
18
作者 赵光明 刘之喜 +1 位作者 孟祥瑞 秦志宏 《采矿与岩层控制工程学报》 EI 北大核心 2024年第1期61-75,共15页
随着煤矿开采向深部逐渐延伸,巷道的大变形和长时间持续流变特性已成为支护中极具挑战的课题之一。为了探究深部巷道围岩损伤劣化的时效特征及动态补强技术,基于实验室试验,并结合理论分析、数值模拟及现场工业试验进行了研究。研究结... 随着煤矿开采向深部逐渐延伸,巷道的大变形和长时间持续流变特性已成为支护中极具挑战的课题之一。为了探究深部巷道围岩损伤劣化的时效特征及动态补强技术,基于实验室试验,并结合理论分析、数值模拟及现场工业试验进行了研究。研究结果表明:(1)基于Laplace逆变换推导出圆形轴对称巷道的变形规律解析解,结合理论分析、非圆形巷道等效变换和现场试验确定塑性区半径为1.5~2.1m,进一步得到直墙半圆拱巷道时效变形解析解;(2)基于弹性与弹塑性巷道模型,采用能量耗散表征了围岩损伤劣化的时效特征与塑性区演化趋势,并提出了一次支护的时机;(3)阐明了围岩在一次支护后的时效性损伤劣化的演化趋势,基于垂直应力峰值比率,提出了二次支护方案与时机,进一步分析围岩剪应力与垂直应力,确定了二次支护锚杆的长度为3.0 m,支护时机为40~70 d。研究结果可为深部煤矿巷道的设计与维护提供理论依据和实践指导。 展开更多
关键词 深部巷道 损伤劣化 时效特征 动态补强
下载PDF
活性依赖性神经保护蛋白在肿瘤中的研究进展
19
作者 胡媛媛 冯同富 《中国医药导报》 CAS 2024年第6期42-45,61,共5页
活性依赖性神经保护蛋白(ADNP)是一种转录因子。近些年来研究发现,ADNP具有染色质重塑、细胞周期与增殖调控、DNA损伤与修复、细胞运动与转移、化疗耐药等肿瘤相关生物学功能,在多种肿瘤中均存在不同程度的突变及异常表达,与肿瘤的发生... 活性依赖性神经保护蛋白(ADNP)是一种转录因子。近些年来研究发现,ADNP具有染色质重塑、细胞周期与增殖调控、DNA损伤与修复、细胞运动与转移、化疗耐药等肿瘤相关生物学功能,在多种肿瘤中均存在不同程度的突变及异常表达,与肿瘤的发生、发展密切相关。本文综述了ADNP的分子结构、功能特点及其在多种肿瘤发生、发展中的研究进展,旨在为肿瘤的诊治研究方向提供新思路。 展开更多
关键词 活性依赖性神经保护蛋白 肿瘤 突变 染色质重塑剂
下载PDF
融合情感语义与句法结构的中文开放域事理图谱构建研究
20
作者 赵又霖 林怡妮 石燕青 《数字图书馆论坛》 2024年第3期12-24,共13页
为解决大规模开放域事理图谱构建过程中缺少标注数据以及事件类型未知导致的限定域事理图谱构建方法难以迁移的问题,利用规则匹配方法高效识别开放域文本中包含的多种事件逻辑关系,融合情感语义与句法结构信息分析提高事件抽取准确性,... 为解决大规模开放域事理图谱构建过程中缺少标注数据以及事件类型未知导致的限定域事理图谱构建方法难以迁移的问题,利用规则匹配方法高效识别开放域文本中包含的多种事件逻辑关系,融合情感语义与句法结构信息分析提高事件抽取准确性,以更好完成事理图谱的构建任务。首先,总结并扩展因果、顺承、条件、转折等多种逻辑关系抽取模板,并基于规则模板、依存句法信息筛选逻辑关系事件句;其次,创新性地引入情感语义分析方法,在句法结构信息的基础上,通过捕获事件及事件间关系的情感语义精准识别事件类型,进而抽取事件论元;再次,计算语义相似度,进行事件融合,构建<前序事件,事件逻辑关系,后序事件>三元组,得到事件事理图谱,并进一步进行事件泛化以构建抽象事理图谱;最后,以事件发展较完整的“2022年猴痘事件”为数据源,通过实证分析证明开放域事理图谱构建方法可以实现不同类型事件的识别、事件间逻辑关系的揭露,其有效性、可行性得到验证。研究不仅弥补了现有事理图谱构建理论的不足,也为决策支持、事件发展预测等提供有力的数据支持。 展开更多
关键词 开放域 事理图谱 依存句法分析 语义依存分析 情感分析
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部