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Establishment of the“4 stages-6 sequences”repair method and quantification analysis on post-earthquake functional recovery of railway station
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作者 Song Jiayu Gao Haiwang +1 位作者 Pan Yi Jiang Junpeng 《Earthquake Engineering and Engineering Vibration》 2025年第3期827-842,共16页
Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the ... Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the establishment of relationships between the station’s function and the damage state,function loss,and failure probability of components and professional equipment in each layer.Also,the“4 stages-6 sequences”post-earthquake repair method is present,taking into account the functional and structural characteristics of railway stations.Additionally,a novel piecewise function for the post-earthquake functional dynamic recovery of railway stations is developed.A case study is conducted on a typical railway station to demonstrate the analysis procedure.Results indicate that under fortification,rare,and extremely rare earthquake scenarios,the interlayer drift ratio(IDR)of the railway station were 1/276,1/143,and 1/52,respectively,and corresponding peak floor acceleration(PFA)were 6.31 m/s^(2),7.82 m/s^(2),and 8.57 m/s^(2),respectively.The post-earthquake function of the railway station was 93.21%,82.33%,and 64.16%of its initial function.The repair times were 6.66 days,18.65 days,and 37.42 days.The displacement-sensitive,non-structural components were identified as the most vulnerable to damage.And the first repair stage(R_(1))which was mainly used to repair structural components and non-structural transport components,accounted for the highest proportion of total repair time. 展开更多
关键词 railway stations seismic response post-earthquake function functional recovery model repair method
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Random testing for system-level functional verification of system-on-chip 被引量:4
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作者 Ma Qinsheng Cao Yang +1 位作者 Yang Jun Wang Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1378-1383,共6页
In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity o... In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity of this method is proven theoretically.Specifically, testcases are generated according to many approaches of randomization.Moreover, the testbench for the system-level verification according to the proposed method is designed by using advanced modeling language.Therefore, under the circumstances that the testbench generates testcases quickly, the hardware/software co-simulation and co-verification can be implemented and the hardware/software partitioning planning can be evaluated easily.The comparison method is put to use in the evaluation approach of the testing validity.The evaluation result indicates that the efficiency of the partition testing is better than that of the random testing only when one or more subdomains are covered over with the area of errors, although the efficiency of the random testing is generally better than that of the partition testing.The experimental result indicates that this method has a good performance in the functional coverage and the cost of testing and can discover the functional errors as soon as possible. 展开更多
关键词 VLSI circuit verification random process function TESTING SYSTEM-ON-CHIP system-level.
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Pigeon Robot for Navigation Guided by Remote Control:System Construction and Functional Verification 被引量:11
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作者 Zhengyue Zhou Denghui Liu +5 位作者 Hong Sun Wenbo Xu Xinmao Tian Xiaoyuan Li Han Cheng Zhenlong Wang 《Journal of Bionic Engineering》 SCIE EI CSCD 2021年第1期184-196,共13页
Animal robots have outstanding advantages over traditional robots in their own energy supplies,orientation,and natural concealment,delivering significant value in the theories and applications of neural science,nation... Animal robots have outstanding advantages over traditional robots in their own energy supplies,orientation,and natural concealment,delivering significant value in the theories and applications of neural science,national security,and other fields.Presently,many animal robots have been fabricated,but researches about the applications of avian robots are still lacking.In this study,we constructed a Pigeon Robot System(PRS),optimized the electric stimulation parameters,assessed the electric stimulus of navigation,and evaluated the navigation efficiency in the field.Biphasic pulse constant current pattern was adapted,and the optimal stimulus parameters of 4 nuclei tested were of amplitude 0.3 mA,5 pulse trains,frequency 25 Hz,5 pulses,and a 25%duty cycle.Effective ratio of left and right steering behavior response to electric stimulus dorsointermedius ventralis anterior nuclei was 67%and 83%,respectively(mean value 75%).Electrical stimulation efficiency was 0.34-0.68 and path efficiency was 0.72-0.85 among pigeon robot individuals in the open field.Neither electrical stimulation efficiency nor path efficiency differed significantly(P>0.05),suggesting that the navigational PRS performance was not biased in either direction.PRS can achieve continuous navigation along simple pathways and provide the necessary application infrastructure and technical reference for the development of animal robot navigation technology. 展开更多
关键词 pigeon robot bionic robot system construction NAVIGATION functional verification
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Verification and validation of a numerical wave tank with momentum source wave generation
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作者 Housheng Zhang Yijing Hu +1 位作者 Biao Huang Xin Zhao 《Acta Mechanica Sinica》 2025年第3期23-38,共16页
systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have bee... systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have been optimized.The H2-5 V&V method involving five mesh sizes with mesh refinement ratio being 1.225 is used to verify the NWT of regular waves,in which the wave height and mass conservation are mainly considered based on a Lv3(H s=0.75 m)and a Lv6(H s=5 m)regular wave.Additionally,eight different sea states are chosen to validate the wave height,mass conservation and wave frequency of regular waves.Regarding the NWT of irregular waves,five different sea states with significant wave heights ranging from 0.09 m to 12.5 m are selected to validate the statistical characteristics of irregular waves,including the profile of the wave spectrum,peak frequency and significant wave height.Results show that the verification errors for Lv3 and Lv6 regular wave on the most refined grid are−0.018 and−0.35 for wave height,respectively,and−0.14 and for−0.17 mass conservation,respectively.The uncertainty estimation analysis shows that the numerical error could be partially balanced out by the modelling error to achieve a smaller validation error by adjusting the mesh size elaborately.And the validation errors of the wave height,mass conservation and dominant frequency of regular waves under different sea states are no more than 7%,8% and 2%,respectively.For a Lv3(H_(s)=0.75 m)and a Lv6(H_(s)=5 m)regular wave,simulations are validated on the wave height in wave development section for safety factors FS≈1 and FS≈0.5-1,respectively.Regarding irregular waves,the validation errors of the significant wave height and peak frequency are both lower than 2%. 展开更多
关键词 verification and validation Wave generation Momentum source function Regular wave Irregular wave Uncertainty estimation
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Feature Mapping and Recuperation by Using Elliptical Basis Function Networks for Robust Speaker Verification
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作者 李昕 郑宇 江芳泽 《Journal of Shanghai University(English Edition)》 CAS 2002年第4期331-336,共6页
The performance of speaker verification systems is often compromised under real world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a... The performance of speaker verification systems is often compromised under real world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a novel method to overcome this problem by using a non linear handset mapper. Under this method, a mapper is constructed by training an elliptical basis function network using distorted speech features as inputs and the corresponding clean features as the desired outputs. During feature recuperation, clean features are recovered by feeding the distorted features to the feature mapper. The recovered features are then presented to a speaker model as if they were derived from clean speech. Experimental evaluations based on 258 speakers of the TIMIT and NTIMIT corpuses suggest that the feature mappers improve the verification performance remarkably. 展开更多
关键词 feature mapping and recurpuration elliptical basis function (EBF) networks speaker verification.
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Transcriptome Analysis and Genes Function Verification of Root Development of Paeonia suffruticosa under Sandy Loam Cultivation
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作者 Yinglong Song Wenqian Shang +7 位作者 Zheng Wang Songlin He Xinya Meng Liyun Shi Yuxiao Shen Dan He Xueyuan Lou Yuke Sun 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第12期2791-2812,共22页
Relatively poor in vitro rooting has limited the large-scale commercial production of tree peony.In this study,on the basis of transcriptome sequencing,differentially expressed genes and the associated metabolic pathw... Relatively poor in vitro rooting has limited the large-scale commercial production of tree peony.In this study,on the basis of transcriptome sequencing,differentially expressed genes and the associated metabolic pathways were identified in tree peony roots at different stages of root formation under sandy loam cultivation.A total of 31.63 Gb raw data were generated and 120,188 unigenes(mean length of 911.98 bp)were annotated according to six databases(NR,NT,GO,KEGG,COG,and Swiss-Prot).Analyses of the ungerminated root primordium period,induced root primordium period,and root formation period detected 8,232,6,907,and 10,687 differentially expressed genes related to 133,132,and 133 metabolic pathways,respectively.Two significantly differentially expressed genes(Unigene13430_All and CL10096.Contig1_All)were associated with the auxin pathway.The full-length Unigene13430_All coding sequence(843 bp)encoded 280 amino acids,whereas the full-length CL10096.Contig1_All coding sequence(1,470 bp)encoded 489 amino acids.Unigene13430_All and CL10096.Contig1_All were identified as IAA gene family members and were respectively named PsIAA27 and PsARF19.The qRT-PCR analysis and functional verification indicated that the expressions of PsARF19 and PsIAA27 in tree peony seedlings,cuttings and grafted seedlings were significant different.PsARF19 promoted root development,it might be a regulatory gene related to the formation of tree peony roots,while PsIAA27 inhibited lateral root development,and it might be involved in controlling auxin sensitivity during root formation.The results of this study may form the basis of future investigations on the mechanism mediating peony root formation.The transcriptome data will be an excellent resource for researchers interested in characterizing the rooting-related tree peony genes. 展开更多
关键词 Tree peony ROOTING RNA-seq CUTTAGE GRAFT functional verification QRT-PCR
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Differing functions of two CYP716 genes for saikosaponin biosynthesis in Bupleurum chinense
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作者 Kaimi Dong Hua Chen +14 位作者 Ma Yu Shiying Wang Xue Yin Chuanxin Mo Meng Zhang Yuchan Li Yong Luo Zeru Yu Zisong Yang Jun Zhao Chao Xin Wenshuai Chen Zhen Ni Zheyong Xue Jianhe Wei 《The Crop Journal》 2026年第1期224-234,共11页
Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the bi... Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the biosynthetic pathway of saikosaponins,we identified two cytochrome P450 monooxygenases,CYP716A41 and CYP716Y4,in Bupleurum chinense.These enzymes catalyze the C-28 oxidation and C-16 hydroxylation of oleanane-type triterpene skeletons,respectively.The catalytic efficiency of CYP716A41 from a southern B.chinense variety was significantly higher than that from a northern variety.Molecular docking and mutagenesis experiments revealed that amino acid residues at sites 9 and 35 may contribute to this difference in catalytic efficiency.Additionally,under cold stress,the expression levels of both CYP450 genes and the saikosaponin contents in the leaves of southern varieties were significantly higher compared to those in northern varieties.The variation in the catalytic efficiency of CYP716A41 and the differential expression of the two CYP450 genes under cold stress during winter are associated with the differences in saikosaponin biosynthesis in the leaves of southern and northern B.chinense varieties.This is consistent with the distinct medicinal usage practices observed between southern and northern China. 展开更多
关键词 Bupleurum chinense Medicinal tissue utilization Saikosaponin biosynthesis pathway CYP716 functional verification
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Assessing building’s post-earthquake functional recovery accounting for utility system disruption
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作者 Negar Mohammadgholibeyki Maria Koliou Abbie B.Liel 《Resilient Cities and Structures》 2023年第3期53-73,共21页
Experience from past earthquakes has demonstrated the need to account for design goals beyond safety,known as functional recovery objectives,in the interest of community resilience.Frameworks have been proposed in the... Experience from past earthquakes has demonstrated the need to account for design goals beyond safety,known as functional recovery objectives,in the interest of community resilience.Frameworks have been proposed in the literature to assess the post-earthquake functional recovery of a building,but without accounting for utility systems’disruption,which may be a key contributor to determining when a building is functional.This paper integrates a previously proposed probabilistic method for estimating the post-earthquake restoration of critical utility services with an individual building’s functional recovery assessment framework.The integration was performed by incorporating utilities into the building system fault trees embedded into a functional recovery framework for various building occupancies(residential and commercial office buildings).Once incorporated,the results are used to interrogate the functional recovery of a reinforced concrete building,and the recovery time results were presented for seven cases investigating contributing factors in the functional recovery results including the number of crews available for lifeline restoration,the effect of low-quality service on meeting tenant requirements for elevators,heating ventilation and air conditioning(HVAC),plumbing and electrical systems,consideration of fire watch,the effect of building seismic retrofit,as well as different cases of fragility functions for the lifeline systems.Results showed that utility systems’disruption does not have a significant impact on the recoccupancy of a building because only one utility-dependent building system(fire suppression)is needed for the building’s safety.Unlike reoccupancy,utility systems are significant for functional recovery,mainly at moderate hazard levels because,at these levels,lifeline networks could be damaged without significant building damage,such that the lifeline systems restoration governs.Buildings with more restrictive tenant requirements are more sensitive to tenant disruptions. 展开更多
关键词 post-earthquake functional recovery Utility service Lifeline recovery Restoration time
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A Survey on an Emerging Safety Challenge for Autonomous Vehicles:Safety of the Intended Functionality 被引量:4
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作者 Hong Wang Wenbo Shao +3 位作者 Chen Sun Kai Yang Dongpu Cao Jun Li 《Engineering》 SCIE EI CAS CSCD 2024年第2期17-34,共18页
As the complexity of autonomous vehicles(AVs)continues to increase and artificial intelligence algorithms are becoming increasingly ubiquitous,a novel safety concern known as the safety of the intended functionality(S... As the complexity of autonomous vehicles(AVs)continues to increase and artificial intelligence algorithms are becoming increasingly ubiquitous,a novel safety concern known as the safety of the intended functionality(SOTIF)has emerged,presenting significant challenges to the widespread deployment of AVs.SOTIF focuses on issues arising from the functional insufficiencies of the AVs’intended functionality or its implementation,apart from conventional safety considerations.From the systems engineering standpoint,this study offers a comprehensive exploration of the SOTIF landscape by reviewing academic research,practical activities,challenges,and perspectives across the development,verification,validation,and operation phases.Academic research encompasses system-level SOTIF studies and algorithm-related SOTIF issues and solutions.Moreover,it encapsulates practical SOTIF activities undertaken by corporations,government entities,and academic institutions spanning international and Chinese contexts,focusing on the overarching methodologies and practices in different phases.Finally,the paper presents future challenges and outlook pertaining to the development,verification,validation,and operation phases,motivating stakeholders to address the remaining obstacles and challenges. 展开更多
关键词 Safety of the intended functionality Autonomous vehicles Artificial intelligence UNCERTAINTY verification Validation
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Development Methodologies for Network Softwarization: A Comparison of DevOps, NetOps, and Verification
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作者 Mehmet Beyaz 《International Journal of Communications, Network and System Sciences》 2023年第5期97-104,共8页
This white paper explores three popular development methodologies for network softwarization: DevOps, NetOps, and Verification. The paper compares and contrasts the strengths and weaknesses of each approach and provid... This white paper explores three popular development methodologies for network softwarization: DevOps, NetOps, and Verification. The paper compares and contrasts the strengths and weaknesses of each approach and provides recommendations for organizations looking to adopt network softwarization. 展开更多
关键词 Development Methodologies Network Softwarization DevOps NetOps verification Software-Defined Networking Network function Virtualization Automation COLLABORATION Testing Validation Network Operations Network Management
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Measuring Fiber Orientation in Nonwoven Fabrics by Laser Scattering Method Part Ⅱ: Algorithm and Verification
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作者 周胜 储才元 严灏景 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期32-36,共5页
The algorithm for evaluation of fiber orientation distribution function (ODF) by laser scattering method based on 2 - dimentional model of fiber arrangement and the method of determining diffuse scattering intensity a... The algorithm for evaluation of fiber orientation distribution function (ODF) by laser scattering method based on 2 - dimentional model of fiber arrangement and the method of determining diffuse scattering intensity are presented. The fiber ODFs of nonwoven samples measured by the computer-program-controlled laser scattering intensity testing system are compared with that of the data obtained by microprojector method. The results show that the algorithm is feasible for assessing the fiber ODFs of nonwoven fabrics manufactured by different processing methods. 展开更多
关键词 fiber orientation distribution Junction laser scattering ALGORITHM verification
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Safety Design and Verification Analysis in the Satellite Development Stage
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作者 REN Xiangwen CHEN Baifeng 《Aerospace China》 2021年第4期21-27,共7页
A safety design applies to every stage in a satellite system development life cycle to identify and analyze hazards in the satellite at a system level, eliminating or controlling various safety risks, while verifying ... A safety design applies to every stage in a satellite system development life cycle to identify and analyze hazards in the satellite at a system level, eliminating or controlling various safety risks, while verifying the functions of the satellite system have safety characteristics, so as to optimize the satellite system for the best performance in terms of time and cost. This article comprehensively leverages such factors as satellite reliability, complexity and life cycle by considering the overall satellite safety work plan, hazard analysis, hazard sources, pyrotechnic devices and other module safety critical designs. Safety design measures were formulated to review and verify the effectiveness of system functions including a safe power supply to a satellite and pyrotechnic explosives to achieve the safety requirements of the satellite from a development stage. Safety design activities for each subsystem will ensure meeting the development requirements of the satellite system as a whole, and ensure the satellite system cannot be the cause of casualties, equipment damage, property loss, or have a health-threatening impact or detrimental impact on the environment. 展开更多
关键词 satellite system development project safety design functional verification
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HashTrie Functional Framework and Its Application in Chinese-English Pattern Matching
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作者 ZUO Zhengkang ZHOU Chao +1 位作者 ZENG Zhicheng WANG Changjing 《Wuhan University Journal of Natural Sciences》 2025年第2期184-194,共11页
Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-... Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-based matching machine demonstrates strong compatibility with both Chinese and English,ensuring high accuracy in text processing and subtree positioning.In this study,a novel functional framework based on the HashTrie structure is proposed and mechanically verified using Isabelle/HOL.This framework is applied to design Functional Multi-Pattern Matching(FMPM),the first functional multi-pattern matching algorithm for Chinese-English mixed texts.FMPM constructs the HashTrie matching machine using character codes and threads the machine according to the associations between pattern strings.The experimental results show that as the stored string information increases,the proposed algorithm demonstrates more significant optimization in retrieval efficiency.FMPM simplifies the implementation of the Threaded Hash Trie(THT)for Chinese-English mixed texts,effectively reducing the uncertainties in the transition from the algorithm description to code implementation.FMPM addresses the problem of space explosion Chinese-English mixed texts and avoids issues such as bound variable iteration errors.The functional framework of the HashTrie structure serves as a reference for the formal verification of future HashTrie-based algorithms. 展开更多
关键词 multi-pattern matching Chinese-English mixed HashTrie functionAL mechanized verification
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桔梗中黄酮类糖基转移酶基因PgUGT72B21的克隆与功能验证
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作者 李涛 郝志鹏 +3 位作者 任星榕 赵钰萤 王彩霞 薛强 《中草药》 北大核心 2026年第1期270-281,共12页
目的以桔梗Platycodon grandiflorus中糖基转移酶为研究对象,进行糖基转移酶PgUGT72B21基因的生物信息学分析、基因克隆与重组质粒构建、蛋白表达与纯化、催化功能验证、酶学性质研究、底物宽泛性考察。方法基于桔梗转录组数据筛选得到... 目的以桔梗Platycodon grandiflorus中糖基转移酶为研究对象,进行糖基转移酶PgUGT72B21基因的生物信息学分析、基因克隆与重组质粒构建、蛋白表达与纯化、催化功能验证、酶学性质研究、底物宽泛性考察。方法基于桔梗转录组数据筛选得到桔梗中关键糖基转移酶PgUGT72B21,进行基因克隆;利用基因重组技术构建了原核表达载体pET-28a-PgUGT72B21,转化至大肠杆菌BL21(DE3)感受态;根据His标签蛋白纯化试剂盒说明进行蛋白纯化,应用SDS-PAGE凝胶电泳检测蛋白的表达情况;通过HPLC和LC-MS系统检测酶促反应产物。结果通过克隆得到的桔梗糖基转移酶基因PgUGT72B21开放阅读框(open reading frame,ORF)长度1407 bp,编码468个氨基酸残基,相对分子质量约为51000,C末端存在高度保守的植物次生产物糖基转移酶(plant secondary product glycosyltransferase,PSPG)基序。系统进化分析表明,该糖基转移酶属于UGT72家族。体外酶促结果显示,PgUGT72B21可催化槲皮素C3位羟基糖基化生成异槲皮苷。通过异源表达与纯化得到重组蛋白后对其酶学性质进行了分析,表明PgUGT72B21催化反应的最适pH为6.0,最适温度为60℃,反应2 h后的底物转化率达到最高。其催化槲皮素的酶动力学参数米氏常数(Km)为390.10μmol/L,转化数(kcat)为11.10/min。进一步的底物宽泛性研究显示PgUGT72B21不仅能够催化槲皮素等黄酮醇类化合物,还能够催化芹菜素等黄酮类化合物。结论发现的新糖基转移酶PgUGT72B21对于丰富糖基化工具酶库具有重要意义,且能为进一步解析桔梗中黄酮糖苷的糖基化过程奠定基础。 展开更多
关键词 桔梗 糖基转移酶 UDP-葡萄糖 槲皮素 功能验证 酶动力学
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RISC-V SBI固件安全启动过程的形式化验证
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作者 杨叶倩 戴鸿君 《计算机研究与发展》 北大核心 2026年第3期768-781,共14页
RISC-V SBI(supervisor binary interface)标准定义了RISC-V架构硬件与操作系统的接口规范。相比x86和ARM固件,SBI固件更合规、可靠;但现有版本仍存在启动正确性未验证、PMP(physical memory protection)物理地址访问等安全漏洞。为此,... RISC-V SBI(supervisor binary interface)标准定义了RISC-V架构硬件与操作系统的接口规范。相比x86和ARM固件,SBI固件更合规、可靠;但现有版本仍存在启动正确性未验证、PMP(physical memory protection)物理地址访问等安全漏洞。为此,提出了定理证明驱动的闭环形式化验证框架,开发经形式验证的SBI固件——SeSBI,并结合Dafny与Isabelle/HOL,以分层策略实现对启动过程的形式验证。为提高验证效率,提出RISC-V硬件模拟策略,统一建模固件与硬件的交互,从而显著降低验证开销。最终成功验证了SeSBI固件启动过程的功能正确性。结果表明,SeSBI以更简洁的代码实现SBI标准启动过程接口,并具备高度可靠性,为RISC-V生态系统提供了经形式验证的可信SBI固件实现。未来工作将扩展验证范围至更多高级属性,并优化验证工具以提升效率。 展开更多
关键词 RISC-V SBI固件 形式化验证 定理证明 功能正确性
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紫丁香So4CL的克隆及功能分析
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作者 倪莹 李雷 +5 位作者 汪进萱 马波 孟昕 冷平生 吴静 胡增辉 《生物技术通报》 北大核心 2026年第1期139-149,共11页
【目的】4-香豆酸∶辅酶A连接酶(4-coumarate:CoA lig-ase,4CL)是苯丙烷代谢途径中的核心酶,克隆并探究4CL基因在紫丁香(Syringa oblata)花青苷合成中的功能。【方法】基于紫丁香基因组及转录组数据筛选并克隆出So4CL基因,对其编码的蛋... 【目的】4-香豆酸∶辅酶A连接酶(4-coumarate:CoA lig-ase,4CL)是苯丙烷代谢途径中的核心酶,克隆并探究4CL基因在紫丁香(Syringa oblata)花青苷合成中的功能。【方法】基于紫丁香基因组及转录组数据筛选并克隆出So4CL基因,对其编码的蛋白进行生物信息学分析和亚细胞定位;利用RT-qPCR研究So4CL在不同花期及不同组织的相对表达量;构建So4CL过表达和沉默载体,利用农杆菌侵染法分别转化紫丁香和烟草(Nicotiana benthamiana),观察其表型变化并测定花青苷含量;通过RTqPCR检测花青苷生物合成途径中So4CL上下游基因的表达水平。【结果】So4CL基因CDS区全长为1659 bp,编码552个氨基酸,具有BOXⅠ和BOXⅡ保守结构域。系统进化分析显示,紫丁香So4CL与水曲柳(Fraxinus mandshurica)的4CL蛋白相似性最高,为97%。RT-qPCR分析结果显示,随着花发育,紫丁香花瓣褪色,So4CL的表达整体呈降低的趋势;So4CL在盛花期中的根、茎、叶、花中均有表达。亚细胞定位分析显示,So4CL主要存在于细胞质上。过表达So4CL的紫丁香花瓣着色明显,花青苷含量显著升高,烟草叶片出现砖红色变化;沉默So4CL后花瓣显著褪色,花青苷含量显著降低;RT-qPCR分析表明,瞬时转化So4CL会影响花青苷生物合成途径中SoPAL、SoCHS、SoDFR和SoUFGT的表达。【结论】So4CL在紫丁香花瓣花青苷合成中发挥着重要作用,是合成关键基因。 展开更多
关键词 紫丁香 4-香豆酸:辅酶A连接酶 花青苷 基因克隆 功能验证 基因表达
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菊花脑芳樟醇合酶(CnTPS2)基因全长克隆及蛋白功能验证
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作者 蒋莉萍 徐宏峰 刘义飞 《世界科学技术-中医药现代化》 北大核心 2026年第1期178-188,共11页
目的获得菊花脑芳樟醇合酶基因,并对其进行分析和功能验证。方法根据菊花脑基因组信息,预测并克隆了菊花脑萜烯类化合物生物合成途径中的关键基因CnTPS2,分别通过原核表达和烟草瞬时表达获取代谢产物并利用GC-MS技术检测其代谢产物。结... 目的获得菊花脑芳樟醇合酶基因,并对其进行分析和功能验证。方法根据菊花脑基因组信息,预测并克隆了菊花脑萜烯类化合物生物合成途径中的关键基因CnTPS2,分别通过原核表达和烟草瞬时表达获取代谢产物并利用GC-MS技术检测其代谢产物。结果挖掘并克隆出片段长为1785 bp的基因CnTPS2;GC-MS数据分析表明CnTPS2基因原核表达产物及烟草瞬时表达产物均含芳樟醇。结论CnTPS2基因可以促进菊花脑芳樟醇的合成积累,该基因为菊花脑芳樟醇合酶基因。 展开更多
关键词 菊花脑 芳樟醇合酶 生物信息学 原核表达 功能验证
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草麻黄SDR基因克隆、表达及功能验证
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作者 陈星星 李佳谕 +4 位作者 张炳琪 郭帅 徐帆 徐江 焦晓林 《核农学报》 北大核心 2026年第2期234-242,共9页
为解析麻黄中苯丙胺类生物碱的生物合成途径,本试验从草麻黄草质茎中克隆了短链脱氢酶/还原酶基因(SDR),构建至pET-32a载体并转化大肠杆菌DH5α,将重组质粒转入大肠杆菌Rosetta(DE3),诱导表达并纯化SDR蛋白,采用气相色谱-质谱联用仪(GC-... 为解析麻黄中苯丙胺类生物碱的生物合成途径,本试验从草麻黄草质茎中克隆了短链脱氢酶/还原酶基因(SDR),构建至pET-32a载体并转化大肠杆菌DH5α,将重组质粒转入大肠杆菌Rosetta(DE3),诱导表达并纯化SDR蛋白,采用气相色谱-质谱联用仪(GC-MS)对SDR蛋白体外酶促转化产物进行了检测,验证其还原功能。结果表明,克隆得到的草麻黄SDR基因长度为756 bp,编码251个氨基酸,相对分子质量为26.65 kDa,属NADB-Rossmann超家族,具有疏水性且无跨膜结构。系统进化分析结果显示草麻黄SDR氨基酸序列与裸子植物柳杉亲缘关系最近。通过原核表达系统,该重组蛋白在大肠杆菌中实现了高效表达。GC-MS检测体外酶促产物表明该重组蛋白可催化底物3,5-双(三氟甲基)苯乙酮还原生成1-(3,5-双(三氟甲基)苯基)乙-1-醇。本试验首次实现了草麻黄SDR基因的克隆与异源表达,并证实其催化氧化还原反应的生物活性。以上研究结果为解析草麻黄苯丙胺类生物碱的合成机制及基因工程改良提供了基础。 展开更多
关键词 草麻黄 短链还原酶 基因克隆 原核表达 功能验证
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改进的基于关联标签的云数据审计方案
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作者 徐晓璇 王绪安 +3 位作者 刘双根 吴立强 张远航 杨晓元 《西安邮电大学学报》 2026年第1期103-111,共9页
为改善典型云存储系统操作日志存在泄露风险的问题,提出一种改进的基于关联标签的云数据审计方案。通过分析基于关联标签的云数据审计方案在标签生成阶段存在的安全性风险,优化构造基于同态哈希函数的关联标签签名,并进行操作日志完整... 为改善典型云存储系统操作日志存在泄露风险的问题,提出一种改进的基于关联标签的云数据审计方案。通过分析基于关联标签的云数据审计方案在标签生成阶段存在的安全性风险,优化构造基于同态哈希函数的关联标签签名,并进行操作日志完整性验证,从而为敏感信息提供隐私保障。安全性分析表明,改进方案在有效处理动态数据的基础上可实现更强的隐私保护。性能分析表明,改进方案计算成本不会随着数据量增大而发生迅速增长,有效提升了计算效率。 展开更多
关键词 标签完整性验证 云存储 云安全 云审计 同态哈希函数
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紫花含笑McERF003调控苯丙烷代谢和高温抗性的功能验证
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作者 丁瑜 余秋岫 +3 位作者 胥芸 陈芷晴 何雯心 刘彩贤 《植物科学学报》 北大核心 2026年第1期74-84,共11页
ERF转录因子家族在植物生长发育、次生代谢以及生物和非生物胁迫响应中发挥重要作用。本研究以紫花含笑(Michelia crassipes Law.)的花被为材料,克隆得到McERF003基因的全长编码序列,对其进行生物信息学分析;利用qRT-PCR分析其在植物不... ERF转录因子家族在植物生长发育、次生代谢以及生物和非生物胁迫响应中发挥重要作用。本研究以紫花含笑(Michelia crassipes Law.)的花被为材料,克隆得到McERF003基因的全长编码序列,对其进行生物信息学分析;利用qRT-PCR分析其在植物不同组织以及非生物胁迫下的表达模式;并构建超表达载体转化烟草(Nicotiana tabacum L.)进行功能验证。结果显示,McERF003编码具有183个氨基酸的蛋白,等电点为9.10,蛋白分子量为20.286 kDa;McERF003基因主要在紫花含笑的根部表达,并响应高温、低温和盐胁迫。与野生型相比,过表达McERF003烟草的花冠和叶片内的类黄酮和木质素含量显著增加;高温胁迫后,转基因植株的萎蔫程度较低,相对电导率和丙二醛(MDA)含量显著低于野生型,可溶性蛋白、脯氨酸、类黄酮和木质素含量均显著高于野生型,抗氧化酶活性也显著增强,表明McERF003过量表达能够显著增加烟草中苯丙烷代谢物类黄酮和木质素的积累,同时增强其高温抗性。 展开更多
关键词 紫花含笑 McERF003 基因克隆 功能验证
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