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Simultaneous identification of multiple animal-derived components in meat and meat products by using MNP marker based on high-throughput sequencing 被引量:1
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作者 Yan Yi Zhanyue Jiang +9 位作者 Lixia Ma Xiaoni Hou Lun Li Deping Ye Juanlan Du Hai Peng Guoquan Han Huaiping Li Jiangwen Tang Lihua Zhou 《Food Science and Human Wellness》 2025年第4期1566-1575,共10页
In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology bas... In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients. 展开更多
关键词 Meat and meat products Multiple nucleotide polymorphism marker method High-throughput sequencing Animal-derived component identification
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Pse-in-One 2.0: An Improved Package of Web Servers for Generating Various Modes of Pseudo Components of DNA, RNA, and Protein Sequences 被引量:12
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作者 Bin Liu Hao Wu Kuo-Chen Chou 《Natural Science》 2017年第4期67-91,共25页
Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and compr... Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and comprehensive as suggested by many users, the updated package has incorporated 23 new pseudo component modes as well as a series of new feature analysis approaches. It is available at http://bioinformatics.hitsz.edu.cn/Pse-in-One2.0/. Moreover, to maximize the convenience of users, provided is also the stand-alone version called “Pse-in-One-Analysis”, by which users can significantly speed up the analysis of massive sequences. 展开更多
关键词 PSEUDO componentS DNA sequenceS RNA sequenceS Protein sequenceS
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Feature-driven topology optimization method preserving component sequences considering turning angle constraint
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作者 Dongsheng Jia Lei Liu +2 位作者 Jihong Zhu Yu Zhang Vassili Toropov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2024年第10期41-56,共16页
Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing ... Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing of continuous fibre-reinforcedpolymer structures, customized stents, and soft robotics parts. This study presents a feature-driven method that preservescomponent sequences accounting for engineering requirements. The chain-of-bars design variables setting scheme is developedto realize the sequential component’s layout, which sets the current bar’s end point as the next bar’s start point. The total lengthof the printing path is constrained to reduce the consumption of material accurately. Also, the angle between adjacent bars isconstrained to avoid sharp angles at the turning point of the 3D printing path. Next, the sensitivity analysis considering theinter-dependence of substructures is performed. Several numerical examples are given to demonstrate the validity and merits ofthe proposed method in designing structures preserving component sequences. 展开更多
关键词 Topology optimization component sequence preservation Chain-like structures Feature-driven method Additive manufacturing
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Disassembly sequence planning using component-joint graph and ant colony optimization
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作者 Zheng Menglei Tian Ling Liu Beibei 《Computer Aided Drafting,Design and Manufacturing》 2016年第1期54-57,共4页
Disassembly sequence planning is an important step of mechanical maintenance. This article presents an integrated study about the generation and optimizing algorithm of the disassembly sequence. Mechanical products ar... Disassembly sequence planning is an important step of mechanical maintenance. This article presents an integrated study about the generation and optimizing algorithm of the disassembly sequence. Mechanical products are divided into two categories of components and connectors. The article uses component-joint graph to represent assembly constraints, including the incidence constraints are represented by incidence matrix and the interference constraints are represented by interference constraints. The inspiring factor and pheromone matrix are calculated according to assembly constraints. Then the ant generates its own disassembly sequences one by one and updates the inspiring factor and pheromone matrix. After all iterations, the best disassembly sequence planning of components and connectors are given. Finally, an application instance of the disassembly sequence of the jack is presented to illustrate the validity of this method. 展开更多
关键词 disassembly sequence planning component-joint graph ant colony algorithms
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Examining gut microbiota and metabolites to clarify mechanisms of Dimocarpus longan Lour leaf components against type 2 diabetes
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作者 Piao-Xue Zheng Chun-Lian Lu +8 位作者 Yan-Li Liang Yu-Ming Ma Jia-Wen Peng Jing-Jing Xie Jia-Li Wei Si-SiChen Zhi-Dong Ma Hua Zhu Jie Liang 《World Journal of Diabetes》 2025年第7期308-327,共20页
AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of ... AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of DLC on the intestinal microbiota in T2DM rats was analyzed via 16S rDNA sequencing.Targeted metabolomics was conducted to evaluate the impact of DLC on the levels of nine short-chain fatty acids(SCFAs).Untargeted metabolomics examined DLC-induced alterations in fecal metabolites and associated metabolic pathways.Additionally,Spearman’s correlation analysis assessed gut microbiota and fecal metabolite relationships.RESULTS DLC significantly attenuated pathological weight loss,reduced fasting blood glucose levels,restored blood sugar homeostasis,and ameliorated dyslipidemia in T2DM rats.The 16S rDNA sequencing revealed that DLC enhanced microbial diversity and reversed intestinal dysbiosis.Targeted metabolomics indicated decreased acetic acid and propionic acid levels and increased butyric acid,isobutyric acid,and 2-methylbutyric acid levels after DLC treatment.Untargeted metabolomics revealed 57 metabolites with altered expression associated with amino acid,carbohydrate,purine,and biotin pathways.The Spearman analysis demonstrated significant links between specific gut microbiota taxa and fecal metabolites.CONCLUSION DLC may exert hypoglycemic effects by modulating intestinal flora genera,SCFA levels,and fecal metabolites. 展开更多
关键词 Dimocarpus longan Lour leaf components Type 2 diabetes 16S rDNA sequencing Short-chain fatty acids Metabolomics
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Unexpected metastasis of intraductal papillary neoplasm of the bile duct without an invasive component to the brain and lungs:A case report 被引量:6
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作者 Nguyen Hai Nam Kojiro Taura +7 位作者 Masashi Kanai Keita Fukuyama Norimitsu Uza Hirona Maeda Yojiro Yutaka Toyofumi F Chen-Yoshikawa Manabu Muto Shinji Uemoto 《World Journal of Gastroenterology》 SCIE CAS 2020年第3期366-374,共9页
BACKGROUND Despite an expanding number of studies on intraductal papillary neoplasm of the bile duct(IPNB),distant metastasis remains unexplained especially in cases of carcinoma in situ.In the present study,we report... BACKGROUND Despite an expanding number of studies on intraductal papillary neoplasm of the bile duct(IPNB),distant metastasis remains unexplained especially in cases of carcinoma in situ.In the present study,we report a rare and interesting case of IPNB without invasive components that later metastasized to lungs and brain.CASE SUMMARY A 69-year-old male was referred to our hospital due to suspected cholangiocarcinoma.Laboratory tests on admission reported a mild elevation of alkaline phosphatase,γ-glutamyl transpeptidase,and total bilirubin in serum.Endoscopic retrograde cholangiography revealed a filling defect in the common bile duct(CBD)extending to the left hepatic duct.Peroral cholangioscopy delineated a tumor in the CBD that had a papillary pattern.Multidetector computed tomography and magnetic resonance cholangiopancreatography detected partial blockage ot interlude in the CBD leading to cholestasis without evidence of metastasis.Therefore,a diagnosis of IPNB cT1N0M0 was established.Left hepatectomy with bile duct reconstruction was performed.Pathological examination confirmed an intraepithelial neoplasia pattern without an invasive component and an R0 resection achievement.The patient was monitored carefully by regular examinations.However,at 32 mo after the operation,a 26 mm tumor in the lungs and a 12 mm lesion in the brain were detected following a suspicious elevated CA 19-9 level.Video-assisted thoracoscopic surgery of left upper lobectomy and stereotactic radiotherapy are indicated.In addition to histopathological results,a genomic profiling analysis using whole exome sequencing subsequently confirmed lung metastasis originating from bile duct cancer.CONCLUSION This case highlights the important role of genomic profiling analysis using whole exome sequencing in identifying the origin of metastasis in patients with IPNB. 展开更多
关键词 Intraductal papillary neoplasm of the bile duct Distant metastasis Invasive component Whole exome sequencing CA 19-9 Case report
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Performance improvement of software component with partial evaluation
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作者 毛宏燕 黄林鹏 李明禄 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第1期95-99,共5页
To avoid the complexity and inefficiency for specific applications of the current software architecture, a novel approach using partial evaluation is proposed to improve the running performance of components. The gene... To avoid the complexity and inefficiency for specific applications of the current software architecture, a novel approach using partial evaluation is proposed to improve the running performance of components. The generic program was specialized into domain-specific realization for the known knowledge and environments. The syntax and semantic(adj.) were analyzed based on byte code instruction sequences, and partial evaluation rules depicted how to perform the specialization. The partial evaluation for object-oriented programs was implemented. The experimental results show that partial evaluation is effective to speed up the running efficiency. The more generality and scalability can be obtained by the integration of partial evaluation with the favorable design mechanisms and compiler optimization technology. 展开更多
关键词 partial evaluation running efficiency component byte code instruction sequence
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An Efficient and Cost-Saving Component Scheduling Algorithm Using High Speed Turret Type Machines for a Board Containing Multiple PCBs
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作者 Wei-Shung Chang Chiuh-Cheng Chyu 《Intelligent Control and Automation》 2011年第2期86-94,共9页
This paper considers a material constrained component scheduling problem during the high speed surface mount manufacturing stage in printed circuit board (PCB) assembly, where each piece of board contains an even numb... This paper considers a material constrained component scheduling problem during the high speed surface mount manufacturing stage in printed circuit board (PCB) assembly, where each piece of board contains an even number of identical PCBs. To accomplish the production, material requirements must be predetermined and incorporated as restraints into the scheduling problem, which has the objective of minimizing production completion time (makespan). A solution procedure is developed based on the following strategies: 1) Each machine is responsible for the same PCBs of each piece, 2) Components of the same types may use one or more feeder locations, 3) Component types are clustered based on their suitable placement speeds, 4) A heuristic using a bottom-up approach is applied to determine the component placement sequence and the feeder location assignment for all machines. Velocity estimate functions of the turret, XY table, and feeder carriage were derived based on empirical data. An experiment using Fuji CP732E machines was conducted on two real life instances. Experimental results indicate that our method performs 32.96% and 10.60% better than the Fuji-CP software for the two instances, in terms of the makespan per piece of board. 展开更多
关键词 Printed Circuit Boards Assembly Surface Mount Technology Heuristics component Placement sequence FEEDER Location Assignment
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Bayesian network structure learning by dynamic programming algorithm based on node block sequence constraints
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作者 Chuchao He Ruohai Di +1 位作者 Bo Li Evgeny Neretin 《CAAI Transactions on Intelligence Technology》 2024年第6期1605-1622,共18页
The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study propose... The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study proposes a DP algorithm based on node block sequence constraints.The proposed algorithm constrains the traversal process of the parent graph by using the M-sequence matrix to considerably reduce the time consumption and space complexity by pruning the traversal process of the order graph using the node block sequence.Experimental results show that compared with existing DP algorithms,the proposed algorithm can obtain learning results more efficiently with less than 1%loss of accuracy,and can be used for learning larger-scale networks. 展开更多
关键词 Bayesian network(BN) dynamic programming(DP) node block sequence strongly connected component(SCC) structure learning
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考虑电感不对称的LFSPM电动机无位置传感器控制与分析
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作者 杜怿 孙可 《江苏大学学报(自然科学版)》 北大核心 2026年第1期64-70,共7页
针对特有的纵向端部效应导致直线电动机三相电感不对称、使得无位置传感器控制位置和速度估计误差中出现交流分量的问题,以一台直线磁通切换永磁(linear flux switched permanent magnet,LFSPM)电动机为对象,提出一种基于二阶陷波器的... 针对特有的纵向端部效应导致直线电动机三相电感不对称、使得无位置传感器控制位置和速度估计误差中出现交流分量的问题,以一台直线磁通切换永磁(linear flux switched permanent magnet,LFSPM)电动机为对象,提出一种基于二阶陷波器的改进型锁相环(phase-locked loop,PLL).首先,建立考虑电感不对称的LFSPM电动机数学模型,基于静止坐标系设计滑模观测器,分析得出电感不对称会使扩展反电动势含正负序分量,导致PLL位置误差出现交流分量且无法被常规PI控制器抑制,并从理论上解释改进PLL抑制位置误差交流分量的原理;其次,基于MATLAB/Simulink搭建了LFSPM电动机无位置传感器控制系统仿真模型,对采用常规和改进型PLL无位置传感器控制效果进行讨论;最后,搭建试验平台并对提出的控制策略进行测试.结果表明:相比于常规无位置控制方法,所提出的基于二阶陷波器的改进型PLL方案可有效提升LFSPM电动机无位置传感器控制精度,将速度误差减小了35.71%,位置误差减小了44.46%,推力脉动减小了12%. 展开更多
关键词 直线磁通切换永磁电动机 无传感器控制 电感不对称 二阶陷波器 滑模观测器 纵向端部效应 锁相环 正负序分量
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酱香白酒酿造大曲微生物群落与白酒挥发性成分关联分析
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作者 孙博林 毛文定 陈茂彬 《酿酒》 2026年第1期40-48,共9页
研究通过高通量测序技术分析不同地区四种酱香型大曲微生物群落组成,并采用GC-MS分析酱香白酒香气成分。结果表明酱香型大曲细菌物种厚壁菌门(Firmicutes)占比最大,其次是放线菌门(Actinobacteriota),最后变形菌门(Proteobacteria)占比... 研究通过高通量测序技术分析不同地区四种酱香型大曲微生物群落组成,并采用GC-MS分析酱香白酒香气成分。结果表明酱香型大曲细菌物种厚壁菌门(Firmicutes)占比最大,其次是放线菌门(Actinobacteriota),最后变形菌门(Proteobacteria)占比最低,主要的真菌微生物属为子囊菌门(Ascomycota)和担子菌门(Basidiomycota)。挥发性成分关联分析表明,泛菌属(Pantoea)、假诺卡氏菌属(Pseudonocardiaceae)、糖多孢菌属(Saccharopolyspora)、魏斯菌属(Weissella)、嗜热子囊菌属(Thermoascus)、链球菌乳球菌属(Lactococcus)、片球菌属(Pediococcus)、芽孢杆菌属(Bacillaceae)、海洋芽孢杆菌属(Oceanobacillus)、曲霉属(Aspergillus)、淡紫拟青霉(Paecilomyces lilacinus)、Rasamsonia属、嗜热真菌属(Thermomyces)、复膜孢酵母属(Saccharomycopsis)对香气成分的产生有一定的相关性。借助探究不同产地酱香型大曲微生物群落组成结构与香气成分的关联性,可为酱香型大曲规范性生产提供理论指导。 展开更多
关键词 高通量测序 酱香型大曲 微生物群落 香气成分
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基于虚拟无功功率方向的有源配电网保护方案
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作者 郭少飞 杨鹏 +3 位作者 徐潜 李铁成 李澳 王彤 《现代电力》 北大核心 2026年第1期81-91,I0002,共12页
新能源多以分布式电源的形式接入配电网,对配电网的故障特征造成了影响,利用本地信息的传统三段式电流保护可靠性难以保证。同时,基于通信系统的纵联保护动作性能受不可测分支影响严重。因此,提出基于虚拟无功功率方向的有源配电网保护... 新能源多以分布式电源的形式接入配电网,对配电网的故障特征造成了影响,利用本地信息的传统三段式电流保护可靠性难以保证。同时,基于通信系统的纵联保护动作性能受不可测分支影响严重。因此,提出基于虚拟无功功率方向的有源配电网保护方案。首先,定义虚拟无功功率的概念,研究故障发生时IIDG的虚拟无功功率输出特征;其次,分析含不可测分支的有源配电网各支路的故障特性;然后,利用5G通信技术和多代理技术构建配电网保护架构,在此架构上提出基于虚拟无功功率方向的保护综合判据;最后,在PSCAD/EMTDC平台进行仿真验证,证实了所提保护方案的有效性。 展开更多
关键词 有源配电网 分布式电源 正序故障分量 不可测分支 5G
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基于DFT重构的改进i_(p)-i_(q)基波正序有功和无功电流检测算法
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作者 李锦彬 朱罗翔 《电气应用》 2026年第1期133-140,共8页
针对传统硬件锁相环i_(p)-i_(q)算法无法实现基波正序有功与无功电流分离的问题,提出了一种基于DFT重构的改进i_(p)-i_(q)检测算法。该算法通过DFT实现αβ轴系下基波电压及其正交量的重构,结合瞬时对称分量变换,完成基波正序、负序电... 针对传统硬件锁相环i_(p)-i_(q)算法无法实现基波正序有功与无功电流分离的问题,提出了一种基于DFT重构的改进i_(p)-i_(q)检测算法。该算法通过DFT实现αβ轴系下基波电压及其正交量的重构,结合瞬时对称分量变换,完成基波正序、负序电压的解耦,为i_(p)-i_(q)算法提供准确的电压相位信息,从而实现基波正序有功、无功电流的检测。与传统的i_(p)-i_(q)法相比,所提改进算法采用数字锁相环,有效解决了电网复杂工况下的电压相位跟踪问题,可准确、快速地提取基波正序有功和无功电流。最后通过仿真和实验验证了该算法的正确性。 展开更多
关键词 锁相环 i_(p)-i_(q)算法 DFT重构 瞬时对称分量法 基波正序有功电流
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Detection Scheme of Positive Sequence Components Based on Operation Period Delay Filter 被引量:2
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作者 Liwei Du Liansong Xiong +3 位作者 Mingxian Li Zhen Tang Liancheng Xiu Xun Ma 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第1期235-243,共9页
Fast and accurate acquisition of positive sequence components of unbalanced grid voltage is an essential requirement to ensure the safety operation of the grid-connected inverter.To improve the extraction speed of pos... Fast and accurate acquisition of positive sequence components of unbalanced grid voltage is an essential requirement to ensure the safety operation of the grid-connected inverter.To improve the extraction speed of positive sequence components of unbalanced voltage,this study proposes a sampling period delay filter(SPDF)to quickly separate positive and negative sequence components by delaying two sampling periods of grid voltage in dq frame.With the SPDF method,only one coordinate transformation is required and the computational burden can be reduced apparently.Then,the noise immunity performance of the proposed SPDF algorithm is investigated;and the corresponding solution,operation period delay filter(OPDF),can guarantee the desired fast response performance under the premise of limiting the amplified noise within the acceptable range.Finally,the feasibility and priority of the above two algorithms have been verified by the simulation and experimental results. 展开更多
关键词 Noise immunity positive sequence components second harmonic components SPDF/OPDF algorithm unbalanced grid voltage
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Cost-effective low-coverage whole-genome sequencing assay for the risk stratification of gastric cancer 被引量:2
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作者 Li-Ping Ye Xin-Li Mao +11 位作者 Xian-Bin Zhou Yi Wang Shi-Wen Xu Sai-Qin He Zi-Liang Qian Xiao-Gang Zhang Li-Juan Zhai Jin-Bang Peng Bin-Bin Gu Xiu-Xiu Jin Ya-Qi Song Shao-Wei Li 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第3期690-702,共13页
BACKGROUND Gastric cancer(GC), a multifactorial disease, is caused by pathogens, such as Helicobacter pylori(H. pylori) and Epstein-Barr virus(EBV), and genetic components.AIM To investigate microbiomes and host genom... BACKGROUND Gastric cancer(GC), a multifactorial disease, is caused by pathogens, such as Helicobacter pylori(H. pylori) and Epstein-Barr virus(EBV), and genetic components.AIM To investigate microbiomes and host genome instability by cost-effective,low-coverage wholegenome sequencing,as biomarkers for GC subtyping.METHODS Samples from 40 GC patients were collected from Taizhou Hospital,Zhejiang Province,affiliated with Wenzhou Medical University.DNA from the samples was subjected to low-coverage wholegenome sequencing with a median genome coverage of 1.86×(range:1.03×to 3.17×) by Illumina×10,followed by copy number analyses using a customized bioinformatics workflow ultrasensitive chromosomal aneuploidy detector.RESULTS Of the 40 GC samples,20 (50%) were found to be enriched with microbiomes.EBV DNA was detected in 5 GC patients (12.5%).H.pylori DNA was found in 15 (37.5%) patients.The other 20(50%) patients were found to have relatively higher genomic instability.Copy number amplifications of the oncogenes,ERBB2 and KRAS,were found in 9 (22.5%) and 7 (17.5%) of the GC samples,respectively.EBV enrichment was found to be associated with tumors in the gastric cardia and fundus.H.pylori enrichment was found to be associated with tumors in the pylorus and antrum.Tumors with elevated genomic instability showed no localization and could be observed in any location.Additionally,H.pylori-enriched GC was found to be associated with the Borrmann type Ⅱ/Ⅲ and gastritis history.EBV-enriched GC was not associated with gastritis.No statistically significant correlation was observed between genomic instability and gastritis.Furthermore,these three different molecular subtypes showed distinct survival outcomes (P=0.019).EBV-positive tumors had the best prognosis,whereas patients with high genomic instability (CIN+) showed the worst survival.Patients with H.pylori infection showed intermediate prognosis compared with the other two subtypes.CONCLUSION Thus,using low-coverage whole-genome sequencing,GC can be classified into three categories based on disease etiology;this classification may prove useful for GC diagnosis and precision medicine. 展开更多
关键词 Gastric cancer Whole-genome sequencing Helicobacter pylori infections Epstein-Barr virus infections Genetic components Precision medicine
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Adaptive Three-phase Estimation of Sequence Components and Frequency Using H∞ Filter Based on Sparse Model 被引量:1
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作者 Umamani Subudhi Harish Kumar Sahoo Sanjeev Kumar Mishra 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2020年第5期981-990,共10页
The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and relay.This paper proposes a new H∞filter based on sparse model to tr... The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and relay.This paper proposes a new H∞filter based on sparse model to track the sequence components and the frequency of three-phase unbalanced power systems.The inclusion of sparsity improves the error convergence behavior of estimation model and hence short-duration non-stationary PQ events can easily be tracked in the time domain.The proposed model is developed using l1 norm penalty in the cost function of H∞filter,which is quite suitable for estimation across all the three phases of an unbalanced system.This model uses real state space modeling across three phases to estimate amplitude and phase parameters of sequence components.However,frequency estimation uses complex state space modeling and Clarke transformation generates a complex measurement signal from the unbalanced three-phase voltages.The state vector used for frequency estimation consists of two state variables.The proposed sparse model is tested using distorted three-phase signals from IEEE-1159-PQE database and the data generated from experimental laboratory setup.The analysis of absolute and mean square error is presented to validate the performance of the proposed model. 展开更多
关键词 sequence component Clarke transformation H∞filter state space model
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Fully Decoupled Branch Energy Balancing Control Method for Modular Multilevel Matrix Converter Based on Sequence Circulating Components 被引量:1
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作者 Zexin Zhao Weijiang Chen +5 位作者 Zhichang Yang Guoliang Zhao Bin Han Yunfei Xu Nianwen Xiang Shulai Wang 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第1期235-247,共13页
The modular multilevel matrix converter(M3C)is a potential frequency converter for low-frequency AC transmission.However,capacitor voltage control of high-voltage and largecapacity M3C is more difficult,especially for... The modular multilevel matrix converter(M3C)is a potential frequency converter for low-frequency AC transmission.However,capacitor voltage control of high-voltage and largecapacity M3C is more difficult,especially for voltage balancing between branches.To solve this problem,this paper defines sequence circulating components and theoretically analyzes the influence mechanism of different sequence circulating components on branch capacitor voltage.A fully decoupled branch energy balancing control method based on four groups of sequence circulating components is proposed.This method can control capacitor voltages of nine branches in horizontal,vertical and diagonal directions.Considering influences of both circulating current and voltage,a cross decoupled control is designed to improve control precision.Simulation results are taken from a low-frequency transmission system based on PSCAD/EMTDC,and effectiveness and precision of the proposed branch energy balancing control method are verified in the case of nonuniform parameters and an unbalanced power system. 展开更多
关键词 Branch energy balancing control decoupled control low-frequency AC transmission modular multilevel matrix converter(M3C) sequence circulating components
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Application of Six-Sequence Fault Components in Fault Location for Joint Parallel Transmission Line 被引量:3
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作者 范春菊 蔡华嵘 郁惟镛 《Tsinghua Science and Technology》 SCIE EI CAS 2005年第2期247-253,共7页
A new fault location method based on six-sequence fault components was developed for parallel lines based on the fault analysis of a joint parallel transmission line. In the six-sequence fault network, the ratio of ... A new fault location method based on six-sequence fault components was developed for parallel lines based on the fault analysis of a joint parallel transmission line. In the six-sequence fault network, the ratio of the root-mean square value of the fault current from two terminals is the function of the line imped- ance, the system impedance, and the fault distance away from the buses. A fault location equation is given to relate these factors. For extremely long transmission lines, the distributed capacitance is divided by the fault point and allocated to the two terminals of the transmission line in a lumped parameter to eliminate the influence of the distributed capacitance on the location accuracy. There is no limit on fault type and syn- chronization of the sampling data. Simulation results show that the location accuracy is high with an average error about 2%, and it is not influenced by factors such as the load current, the operating mode of the power system, or the fault resistance. 展开更多
关键词 fault location joint parallel line six-sequence components two-terminal
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Study on the Effect of Variation of Flow in Sequencing Batch Reactor Using PCA and ANOVA
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作者 Govindasamy Vijayan R. Saravanane T. Sundararajan 《Journal of Geoscience and Environment Protection》 2017年第4期56-74,共19页
Wastewater treatment using Sequencing Batch Reactor (SBR) technology is one of the state-of-the art wastewater management systems. In this technology equalization, biological treatment and secondary clarification are ... Wastewater treatment using Sequencing Batch Reactor (SBR) technology is one of the state-of-the art wastewater management systems. In this technology equalization, biological treatment and secondary clarification are performed in a single reactor in a time control sequence. SBR system is idler for the areas where the available land is limited, since it operates in less space and very cost effective even on small scales. The control of the operational parameters during the process of biological wastewater treatment is often complicated due to the dynamic change in the composition and characteristics of the raw wastewater, flow rates and other parameters influencing the complex nature of the treatment process and the process in SBR has a unique cyclic batch operation. The performance of the SBR was studied using pilot and real plant at Puducherry. The parameters considered in this study are flow, Mixed Liquor Suspended Solids (MLSS), pH, temperature, influent and effluent of Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD). As a part of the study, the effect of constant flow and varying flow on the organic loading of the influent TSS, BOD and COD and their influence on the organic load of the effluent parameters were examined to identify the level of significance of the parameters in relation to the flow. The impact of flow on other parameters was also examined. The experimental data obtained from pilot and real plants were analyzed using multi variate statistical analyses like correlation analysis, Principal Component Analysis (PCA) and Analysis of variance (ANOVA). The statistical analysis revealed that constant flow had no significant role and the influent parameters alone had the critical role, whereas varying flow as well as the influent parameters had the significant role on the performance of SBR. 展开更多
关键词 sequencING BATCH Reactor (SBR) Mixed LIQUOR Suspended Solids (MLSS) Principal component ANALYSIS (PCA) ANALYSIS of Variance (ANOVA)
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挖掘机工作过程动力特性仿真及主构件参数多目标优化设计方法 被引量:2
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作者 林述温 陆哲 +3 位作者 危世佳 陈剑雄 顾天奇 谢钰 《中国机械工程》 北大核心 2025年第6期1371-1379,共9页
现有挖掘机主构件参数优化设计方法无法保证挖掘作业全过程多工况位置工作性能最优,且没有考虑作业过程中的能耗特性。研究了以典型工况作业全过程动力和能耗特性为目标的挖掘机工作装置主构件参数多目标优化设计方法。通过对基于ADAMS... 现有挖掘机主构件参数优化设计方法无法保证挖掘作业全过程多工况位置工作性能最优,且没有考虑作业过程中的能耗特性。研究了以典型工况作业全过程动力和能耗特性为目标的挖掘机工作装置主构件参数多目标优化设计方法。通过对基于ADAMS的参数化挖掘机虚拟样机的动力学仿真,分析了四种典型工况作业过程的液压缸驱动力和功率特性,确定了工作装置的优化工况,建立了新的综合考虑挖掘机典型工况作业过程液压缸驱动力传动比和功率特性的多目标优化数学模型,并结合实例对挖掘机整机工作装置参数化虚拟样机的铲斗、斗杆和动臂主构件参数进行顺序多目标优化。优化结果表明:该优化设计方法可显著提高挖掘机作业全过程工作装置传递动力的性能,降低液压缸能耗。 展开更多
关键词 挖掘机 主构件参数 虚拟样机 过程特性 多目标优化 顺序优化
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