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肝细胞肝癌组织中WDR4和EIF2A的表达及临床预后价值
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作者 陶珊珊 王竞 黄桂春 《徐州医科大学学报》 CAS 2024年第2期112-118,共7页
目的探讨肝细胞肝癌(HCC)组织中WD重复结构域4(WDR4)、真核翻译起始因子2A(EIF2A)的表达情况及临床预后意义。方法收集2019年1月—2020年1月南京大学医学院附属金陵医院收治的90例HCC患者的临床资料。利用R语言(4.2.1版本)分析癌症基因... 目的探讨肝细胞肝癌(HCC)组织中WD重复结构域4(WDR4)、真核翻译起始因子2A(EIF2A)的表达情况及临床预后意义。方法收集2019年1月—2020年1月南京大学医学院附属金陵医院收治的90例HCC患者的临床资料。利用R语言(4.2.1版本)分析癌症基因组图谱(TCGA)数据库下载的327对HCC癌组织和癌旁组织中WDR4 mRNA、EIF2A mRNA表达的转录组测序数据。免疫组织化学检测HCC癌组织、癌旁组织中WDR4、EIF2A表达。分析HCC癌组织WDR4、EIF2A表达与临床病理特征的关系。Kaplan-Meier法分析WDR4、EIF2A表达对HCC患者预后的影响。Cox回归模型分析HCC预后的影响因素。结果HCC癌组织WDR4 mR-NA、EIF2A mRNA表达高于癌旁组织,差异有统计学意义(P均<0.05)。HCC癌组织中WDR4、EIF2A表达阳性率高于癌旁组织,差异有统计学意义(P均<0.05)。HCC癌组织WDR4 mRNA与EIF2A mRNA表达呈正相关(r=0.404,P<0.001)。HCC癌组织中WDR4蛋白与EIF2A蛋白表达呈正相关(r=0.667,P<0.05)。肿瘤最大径>5 cm、TNM分期Ⅲ期及浸润型HCC癌组织中WDR4、EIF2A阳性率分别高于肿瘤最大径≤5 cm、TNM分期Ⅰ-Ⅱ期及非浸润型癌组织,差异有统计学意义(P均<0.05)。WDR4阳性组3年累积生存率明显低于WDR4阴性组,差异有统计学意义(P=0.016)。EIF2A阳性组3年累积生存率明显低于EIF2A阴性组,差异有统计学意义(P=0.022)。肿瘤TNM分期Ⅲ期、肿瘤最大径>5 cm、WDR4阳性、EIF2A阳性是HCC患者不良预后的独立危险因素。结论HCC组织中WDR4、EIF2A表达升高,两者与HCC不良临床病理特征有关,是评估HCC预后的肿瘤标志物。 展开更多
关键词 肝细胞肝癌 wd重复结构域4 真核翻译起始因子2A 临床病理特征 预后
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A real-time AI-assisted seismic monitoring system based on new nodal stations with 4G telemetry and its application in the Yangbi M_(S) 6.4 aftershock monitoring in southwest China 被引量:2
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作者 Junlun Li Huajian Yao +10 位作者 Baoshan Wang Yang Yang Xin Hu Lishu Zhang Beng Ye Jun Yang Xiaobin Li Feng Liu Guoyi Chen Chang Guo Wen Yang 《Earthquake Research Advances》 CSCD 2022年第2期3-10,共8页
A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.Howeve... A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.However,it is rather difficult for current seismic nodal stations to transmit data in real time for an extended period of time,and it usually takes a great amount of time to process the acquired data manually.To monitor earthquakes in real time flexibly,we develop a mobile integrated seismic monitoring system consisting of newly developed nodal units with 4G telemetry and a real-time AI-assisted automatic data processing workflow.The integrated system is convenient for deployment and has been successfully applied in monitoring the aftershocks of the Yangbi M_(S) 6.4 earthquake occurred on May 21,2021 in Yangbi County,Dali,Yunnan in southwest China.The acquired seismic data are transmitted almost in real time through the 4G cellular network,and then processed automat-ically for event detection,positioning,magnitude calculation and source mechanism inversion.From tens of seconds to a couple of minutes at most,the final seismic attributes can be presented remotely to the end users through the integrated system.From May 27 to June 17,the real-time system has detected and located 7905 aftershocks in the Yangbi area before the internal batteries exhausted,far more than the catalog provided by China Earthquake Networks Center using the regional permanent stations.The initial application of this inte-grated real-time monitoring system is promising,and we anticipate the advent of a new era for Real-time Intelligent Array Seismology(RIAS),for better monitoring and understanding the subsurface dynamic pro-cesses caused by Earth's internal forces as well as anthropogenic activities. 展开更多
关键词 Seismic dense array 4G data transmission real-time earthquake monitoring Machine-learning assisted processing real-time intelligent array seismology
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A Novel Real-Time State-of-Health and State-of-Charge Co-Estimation Method for LiFePO_4 Battery
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作者 乔荣学 张明建 +3 位作者 刘屹东 任文举 林原 潘锋 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期182-185,共4页
The state of charge (SOC) and state of health (SOH) are two of the most important parameters of Li-ion batteries in industrial production and in practical applications. The real-time estimation for these two param... The state of charge (SOC) and state of health (SOH) are two of the most important parameters of Li-ion batteries in industrial production and in practical applications. The real-time estimation for these two parameters is crucial to realize a safe and reliable battery application. However, this is a great problem for LiFePO4 batteries due to the large constant potential plateau in the charge/discharge process. Here we propose a combined SOC and SOH co-estimation method based on the experimental test under the simulating electric vehicle working condition. A first-order resistance-capacitance equivalent circuit is used to model the battery cell, and three parameter values, ohmic resistance (Rs), parallel resistance (Rp) and parallel capacity (Cp), are identified from a real-time experimental test. Finally we find that Rp and Cp could be utilized to make a judgement on the SOIl. More importantly, the linear relationship between Cp and the SOC is established to make the estimation of the SOC for the first time. 展开更多
关键词 of in is on SOC A Novel real-time State-of-Health and State-of-Charge Co-Estimation Method for LiFePO4 Battery SOH for
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Optimization of Quantitative Real-time PCR System on Amplification of Beta-glucosidase Gene Os1bglu4
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作者 Rouyi CHEN Jiang CHENG +2 位作者 Changxiang ZHENG Minna PAN Mariena KETUDAT-CAIRNS 《Agricultural Science & Technology》 CAS 2014年第7期1105-1108,1218,共5页
[Objective] This study aimed to establish a quantitative real-time PCR (qRT-PCR) system for detecting the expression of rice beta-glucosidase gene Os1bglu4.[Method] The PCR was conducted with SYBR Green Ⅰ method,us... [Objective] This study aimed to establish a quantitative real-time PCR (qRT-PCR) system for detecting the expression of rice beta-glucosidase gene Os1bglu4.[Method] The PCR was conducted with SYBR Green Ⅰ method,using the primers of reference gene actin or ubiquitin.[Result] Actin was more suitable to be the reference gene than ubiquitin.More accurate results were obtained when the 100 ng cDNA template was added at a large volume and a lower concentration.The primer concentration in the range from 0.2 to 0.8 μmol/L we set had no significant influence on the results,so,0.4 μmol/L was selected as the optimal primer concentration in this study.The amplification efficiency was greatly reduced when the annealing temperature was set at 64 ℃,therefore,annealing temperature was set at 60 ℃.Compared with the reaction system of 25 μl,the fluorescence intensity was significantly lower but the CT value did not change greatly in 10 μl system.So,the 10 μl reaction system was selected,which significantly reduces the research costs for the detection of a large amount of samples in future study. 展开更多
关键词 RICE Β-GLUCOSIDASE Quantitative real-time PCR Os1bglu4
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Instantaneous Real-Time Detection Technology of GLI on FY-4 Geostationary Meteorological Satellite
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作者 BAO Shutong LI Yunfei +2 位作者 TANG Shaofan LIANG Hua ZHAO Xuemin 《Aerospace China》 2017年第2期23-30,共8页
Lightning is a typical example of an instantaneous random point source target. It has close connection with severe convective phenomena such as a thunderstorm, whose distribution, variation, position and forecasting c... Lightning is a typical example of an instantaneous random point source target. It has close connection with severe convective phenomena such as a thunderstorm, whose distribution, variation, position and forecasting can be acquired through lightning observation. In this paper, we discuss the way to achieve instantaneous lightning signal intensification and detection from geostationary orbit by using the differences between the lightning signal and the slowly changing background noise such as that of cloud, land and ocean, combining three methods, spectral filtering, spatial filtering and background noise, enabling removal between frames. After six months of operation in orbit, lightning within the coverage of the Geostationary Lightning Imager was effectively detected, strongly supporting the case for shorttime and real-time early warning, forecasting and tracking of severe convective phenomena in China. 展开更多
关键词 FY-4 Geostationary Lightning Imager instantaneous lightning real-time detection severe convectivephenomena
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电子控制最佳扭矩分配4WD系统研究 被引量:23
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作者 郭立书 葛安林 +1 位作者 张泰 岳英杰 《农业机械学报》 EI CAS CSCD 北大核心 2002年第6期16-19,共4页
通过对行星齿轮式分动器工作过程的分析 ,以提高运动性能和行驶安全稳定性能、减少轮胎磨损为目的 ,研究提出一种新的控制前后传动轴扭矩分配的系统。根据前输出轴转速、后输出轴转速、方向盘转角和制动开关等信息 ,分正常、起步、转向... 通过对行星齿轮式分动器工作过程的分析 ,以提高运动性能和行驶安全稳定性能、减少轮胎磨损为目的 ,研究提出一种新的控制前后传动轴扭矩分配的系统。根据前输出轴转速、后输出轴转速、方向盘转角和制动开关等信息 ,分正常、起步、转向、制动、滑转控制和转速差控制等 6种工况 ,制定最佳扭矩分配方案 ,对系统实施控制。试验结果表明该系统明显优于其他四轮驱动 (4WD) 展开更多
关键词 电子控制 扭矩 4wd系统 分动器 汽车 行走系统
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基于EtherCAT实时以太网的48英寸转鼓4WD汽车交流电惯量底盘测功机的设计 被引量:2
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作者 张坤良 彭秀英 +6 位作者 王嘉钧 洪彬 李志宏 黄志勇 庞晓伟 李建兴 李江威 《小型内燃机与车辆技术》 2016年第4期55-58,共4页
根据车辆底盘测试技术的特点,将EtherCat总线系统引入到车辆测试中,开发出基于EtherCAT实时以太网的4WD汽车底盘测功机。通过采用实时以太网技术以及多传感器采集和变频控制技术等多技术相融合方式,构建了汽车功率、排放、滑行、加速、... 根据车辆底盘测试技术的特点,将EtherCat总线系统引入到车辆测试中,开发出基于EtherCAT实时以太网的4WD汽车底盘测功机。通过采用实时以太网技术以及多传感器采集和变频控制技术等多技术相融合方式,构建了汽车功率、排放、滑行、加速、动力等不同工况性能测试的平台。实车测试证明,该测试平台测试结果准确、可靠。 展开更多
关键词 ETHERCAT 实时以太网 4wd汽车底盘测功机
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4WD电动汽车转速闭环控制 被引量:3
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作者 卓桂荣 余卓平 +1 位作者 陈惠 陈辛波 《汽车技术》 北大核心 2004年第12期18-22,共5页
研究了4WD电动汽车的转速闭环控制。提出了模型跟踪2自由度转速闭环控制策略和基于观测器的车速估算方法。介绍了该控制方法的基本原理及实现技术。通过轮毂电机加载试验台的硬件在回路仿真、9自由度整车模型弯道制动及分离系数路面仿真... 研究了4WD电动汽车的转速闭环控制。提出了模型跟踪2自由度转速闭环控制策略和基于观测器的车速估算方法。介绍了该控制方法的基本原理及实现技术。通过轮毂电机加载试验台的硬件在回路仿真、9自由度整车模型弯道制动及分离系数路面仿真,验证了该控制方法的有效性。 展开更多
关键词 电动汽车 4wd 驱动防滑 横摆力矩控制
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粘性联轴节在4WD汽车上的应用 被引量:7
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作者 马天飞 王云成 林洪月 《兵工学报(坦克装甲车与发动机分册)》 1999年第1期49-54,共6页
该文介绍了粘性联轴节技术的发展.在分析粘性联轴节特性的基础上, 讨论了它在4WD汽车上的应用.
关键词 粘性联轴节 4wd汽车 轴间差速器 行驶性能
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基于ADAMS与Matlab联合仿真的4WD电动汽车模型建立 被引量:3
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作者 卢艳楠 周建辉 +1 位作者 岳立喜 马雷 《农业装备与车辆工程》 2012年第8期21-25,共5页
分析四轮独立驱动电动汽车各部分的工作组成,根据实验样车数据,使用ADAMS软件建立了整车的动力学模型和Matlab软件建立电机模型,驱动控制系统模型,发挥ADAMS软件和Matlab软件各自优点进行了联合仿真实验。对比场地实验表明该方法能较好... 分析四轮独立驱动电动汽车各部分的工作组成,根据实验样车数据,使用ADAMS软件建立了整车的动力学模型和Matlab软件建立电机模型,驱动控制系统模型,发挥ADAMS软件和Matlab软件各自优点进行了联合仿真实验。对比场地实验表明该方法能较好地模拟电动汽车控制过程中的电机及车辆状态变化情况,证明联合仿真模型满足仿真实验要求,为后续复杂环境下的实验提供理论参考。 展开更多
关键词 电动汽车 4wd 联合仿真 ADAMS MATLAB
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基于信号采集的电动4WD汽车滑转率计算的研究 被引量:1
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作者 桂临秋 罗杰 秦凯 《武汉理工大学学报(交通科学与工程版)》 2017年第2期344-348,共5页
利用GPS/INS组合系统和基于BP神经网络的车轮状态识别与车速估计系统获取汽车纵向速度.根据GPS的运行情况,当GPS信号在锁时,利用GPS/INS组合系统获取汽车纵向速度并训练BP神经网络;当GPS信号失锁时,利用BP神经网络识别车轮状态为打滑状... 利用GPS/INS组合系统和基于BP神经网络的车轮状态识别与车速估计系统获取汽车纵向速度.根据GPS的运行情况,当GPS信号在锁时,利用GPS/INS组合系统获取汽车纵向速度并训练BP神经网络;当GPS信号失锁时,利用BP神经网络识别车轮状态为打滑状态或者滚转状态,根据车轮状态结合汽车纵向加速度和车轮线速度计算汽车的纵向速度.通过实际的道路实验,验证了整个系统对汽车纵向速度获取的精确度,证实了该方法的可行性与可靠性. 展开更多
关键词 电动4wd汽车 驱动防滑 GPS/INS系统 BP神经网络
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4WD/WS电动车辆稳定性分层控制与轮胎力优化分配算法研究 被引量:1
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作者 孟腾飞 田晋跃 郑师虔 《机电工程》 CAS 北大核心 2018年第3期317-322,共6页
针对车辆稳定性分析中的运算难以解耦和轮胎力优化分配问题,对四轮独立驱动/转向电动车辆进行研究,提出了一种分层集成控制算法。上层力矩控制层以理想线性车辆模型输出作为控制目标,采用了滑模控制算法决策出车辆稳定所需施加的总的纵... 针对车辆稳定性分析中的运算难以解耦和轮胎力优化分配问题,对四轮独立驱动/转向电动车辆进行研究,提出了一种分层集成控制算法。上层力矩控制层以理想线性车辆模型输出作为控制目标,采用了滑模控制算法决策出车辆稳定所需施加的总的纵向力、侧向力和横摆力矩;下层力矩分配层,设计了带权重目标函数,充分考虑了轮胎力,在确保每个车轮都工作在稳定区域的前提下,把4个车轮的转向角和驱动力矩作为8个独立的控制变量,从而把车体运动所需的总控制力转化为控制变量的具体值,作为集成控制器的输出;选用低附着路面,设计了Carsim/Simulink联合仿真实验。研究结果表明:该分层集成控制算法能够很好地跟随驾驶员意图,确保车辆稳定行驶。 展开更多
关键词 4wd/WS电动车辆 轮胎力 车辆稳定性 分层控制算法
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A Novel 4WD Electric Vehicle Control Strategy Based on Direct Torque Control Space Vector Modulation Technique 被引量:1
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作者 Brahim Gasbaoui Abdelfatah Nasri 《Intelligent Control and Automation》 2012年第3期236-242,共7页
Four-Wheels-Drive (4WD) electric Vehicle (EV) controlled with Direct Torque Control based Space Vector Modulation (DTC-SVM) is presented, where the electrical traction chain was well analyzed and studied from the lith... Four-Wheels-Drive (4WD) electric Vehicle (EV) controlled with Direct Torque Control based Space Vector Modulation (DTC-SVM) is presented, where the electrical traction chain was well analyzed and studied from the lithium battery, the buck boost to the mechanical load behavior. The speed of four wheels is calculated independently during the turning with the electronic differential system computations which distributes torque and power to each in-wheel motor according to the requirements, adapts the speed of each motor to the driving conditions. The basic idea of this work is to maintain the initial battery state of charge (SOC) equal to 70% and the prototype was tested in several topology conditions and under speed. The simulations carried in Matlab/Simulink verified the efficiency of the proposed DTC-SVM controller, and show that the system has more favorable dynamic performance. Results also indicate that this strategy can be successfully implemented into the traction drive of the modern 4WD electric vehicles. 展开更多
关键词 4wd SVM-DTC CONTROL ELECTRIC VEHICLE SOC
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Artificial Intelligence Application’s for 4WD Electric Vehicle Control System 被引量:1
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作者 Abdelfatah Nasri Brahim Gasbaoui 《Intelligent Control and Automation》 2012年第3期243-250,共8页
A novel speed control design of 4WD electric vehicle (EV) to improve the comportment and stability under different road constraints condition is presented in this paper. The control circuit using intelligent adaptive ... A novel speed control design of 4WD electric vehicle (EV) to improve the comportment and stability under different road constraints condition is presented in this paper. The control circuit using intelligent adaptive fuzzy PI controller is proposed. Parameters which guide the functioning of PI controller are dynamically adjusted with the assistance of fuzzy control. The 4WD is powered by four motors of 15 kilowatts each one, delivering a 384 N.m total torque. Its high torque (338 N.m) is instantly available to ensure responsive acceleration performance in built-up areas. The electric drive canister of tow directing wheels and tow rear propulsion wheels equipped with tow induction motors thanks to their light weight simplicity and their height performance. Acceleration and steering are ensure by electronic differential, the latter control separately deriving wheels to turn at any curve. Electric vehicle are submitted different constraint of road using direct torque control. Electric vehicle are simulated in MATLAB SIMULINK. The simulation results have proved that the intelligent fuzzy PI control method decreases the transient oscillations and assure efficiency comportment in all topologies road constraints, straight, curved road, descent. 展开更多
关键词 4wd PI Adaptive FUZZY PI FUZZY CONTROLLER Direct TORQUE Control.SOC
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Identification of T-DNA Inserted Mutant Gene Transcription by Using Real-time PCR in Arabidopsis
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作者 YUAN Man BAI Xi CAI Hua LI Yong JI Wei ZHU Yanming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期41-47,共7页
AtERF4 (ethylene response factor) is a negative regulator in jasmonic acid mediated signal transduction pathway and ethylene mediated signal transduction pathway of Arabidopsis. It could respond to abscisic acid (... AtERF4 (ethylene response factor) is a negative regulator in jasmonic acid mediated signal transduction pathway and ethylene mediated signal transduction pathway of Arabidopsis. It could respond to abscisic acid (ABA) and ethylene stimulus ATSYR1 gene encodes a syntaxin localizing at the plasma membrane in Arabidopsis, which can be induced by abiotic stress. To identify mutation lines for gene functional analysis, real-time PCR was employed to detect the expression level of AtERF4 and ATSYR1 in homozygous T-DNA insertion mutant line, respectively. Real-time PCR is a powerful tool which can be used to detect steady-state mRNA levels specifically, sensitively and reproducibly. Comparing to other forms of quantitative RT-PCR, the amount of amplified products can be detected by real-time PCR instantly and thus is a preferable alternative. In this study, RNA with T-DNA inserting into exon could be detected in AtERF4 knock-out mutation line. The results indicated that AtERF4 had been trucked in transcription level. On the other hand, T-DNA inserting into the promoter of gene ATSYR1 had no effect on reducing the expression level ofATSYR1 gene. Further molecular and phenotype studies now are ongoing to clarify the potential consequences of AtERF4 and ATSYR1 deficiency in Arabidopsis 展开更多
关键词 Arabidopsis thaliana ERF4 SYR1 T-DNA insertion real-time PCR
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Comparison of Two Real-time PCR Technigues for Quantification of GMO Contents in Highly Processed Products of Soybean
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作者 YU Yanbo GAO Xuejun ZHANG Minghui LI Lu AO Jinxia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第1期37-42,共6页
The RR soybean was quantitatively detected by ABI Prism 7300 sequence detector with PCR primers and fluorescence probes were designed according to the sequences of endogenous Lectin gene and exogenous CP4-EPSPS gene, ... The RR soybean was quantitatively detected by ABI Prism 7300 sequence detector with PCR primers and fluorescence probes were designed according to the sequences of endogenous Lectin gene and exogenous CP4-EPSPS gene, and the PCR systems were based on SYBR Green I and TaqMan. The standard curve of ACt between CP4-EPSPS gene and Lectin gene of the RR soybean in standard materials was generated and a linear regression equation was obtained. Quantification methods were optimized through two different real-time PCR chemistries, i.e. SYBR Green I and TaqMan, and the RR soybean contents were quantified in five standard samples and seven highly processed products by the two assays. Both methods are proved to be specific, highly sensitive and reliable for both identification and quantification of soybean DNA. The results indicate that the two optimized PCR system can be used for the practical quantitative detection of RR soybean in highly processed products. 展开更多
关键词 RR soybean highly processed products CP4-EPSPS gene real-time PCR SYBR Green I TAQMAN
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Study of engaged performance regulation in controlled transfer clutch of 4WD car based on genetic sliding mode control
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作者 Zhang Yang Men Yongxin +1 位作者 Li Wei Ma Mingtu 《Engineering Sciences》 EI 2014年第5期38-44,共7页
This paper investigates an approach to improve the engagement quality of controlled transfer clutch mode in 4 wheel drive(WD) car from three considerations of reducing friction,smoothening responsiveness and alleviati... This paper investigates an approach to improve the engagement quality of controlled transfer clutch mode in 4 wheel drive(WD) car from three considerations of reducing friction,smoothening responsiveness and alleviating jerk.The method utilizes an improved sliding mode control with genetic algorithm instead of simplified mode to determine appropriate values of parameters in control close- loop.The simulation results show that the method is effective for improving the engagement quality of coupling satisfying different design needs for 4WD car,as well as robustness even if input torque is changed at a certain range. 展开更多
关键词 4wd transfer clutch sliding mode control genetic algorithm
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低坎高就 RAV4 2.0L 4WD
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作者 WILL 《产品可靠性报告》 2011年第11期18-19,共2页
长假刚刚过去,伴随着各个景点浏览数字此起彼伏地被刷新,身边也传来了这样或那样“被拥挤,走失或丢鞋”的故事,人们需要这样一款车:它能令你暂时挣脱都市的禁锢,远离钢筋水泥筑成的壁垒,能使灵魂得以彻底的释放。信马由缰,而且... 长假刚刚过去,伴随着各个景点浏览数字此起彼伏地被刷新,身边也传来了这样或那样“被拥挤,走失或丢鞋”的故事,人们需要这样一款车:它能令你暂时挣脱都市的禁锢,远离钢筋水泥筑成的壁垒,能使灵魂得以彻底的释放。信马由缰,而且越远越好。 展开更多
关键词 RAV42.0L4wd 轿车 四轮驱动系统 排量
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黄海304(4WD)型轮式拖拉机
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《农业机械》 2003年第6期57-57,共1页
黄海金马轮式拖拉机系列产品具有牵引力大、油耗低、功能多、操作方便、用途广泛和使用可靠等特点,适用于旱田、丘陵、菜园、园艺和多种农田作业,更是短途运输的理想工具,另可外选配有液压转向、驾驶室。
关键词 黄海304(4wd)型轮式拖拉机 技术参数 外形尺寸 整机质量 发动机
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猪TLR4基因在F18大肠杆菌抗性型和敏感型资源群体间的差异表达分析 被引量:7
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作者 包文斌 潘章源 +6 位作者 朱璟 叶兰 杜子栋 蔡家嘉 黄小国 朱国强 吴圣龙 《畜牧兽医学报》 CAS CSCD 北大核心 2011年第2期278-283,共6页
本研究旨在检测TLR4基因mRNA在猪各个组织的分布以及在F18大肠杆菌抗性型和敏感型群体间差异表达水平,为探讨该基因在免疫识别和F18大肠杆菌抗性中发挥的作用提供理论依据。本试验运用SYBR GreenⅠ实时荧光定量PCR技术进行定量测定。首... 本研究旨在检测TLR4基因mRNA在猪各个组织的分布以及在F18大肠杆菌抗性型和敏感型群体间差异表达水平,为探讨该基因在免疫识别和F18大肠杆菌抗性中发挥的作用提供理论依据。本试验运用SYBR GreenⅠ实时荧光定量PCR技术进行定量测定。首先,各取8头35日龄F18大肠杆菌抗性型和敏感型苏太仔猪组织样,包括心脏、肝脏、脾脏等11个组织,提取总RNA,以GAPDH基因为内参基因,进行实时荧光定量PCR。对TLR4基因mR-NA进行均一化处理,利用荧光阈值(Ct值)计算TLR4基因mRNA在各个组织以及F18大肠杆菌抗性型和敏感型群体间表达量。结果显示,TLR4 mRNA在猪各种组织中广泛表达,在肺、淋巴结、肾脏和脾脏等免疫器官中表达量较高,F18大肠杆菌敏感型的TLR4基因表达量普遍高于抗性型个体的表达量,在各个组织中(除胃外)TLR4表达量差异倍数从1.083到2.980不等;在肺、淋巴结、肾脏和胸腺组织中,F18大肠杆菌敏感型的TLR4基因表达量显著高于抗性型个体的表达量(P<0.05)。本研究结果表明,TLR4基因通过天然免疫识别机制对猪F18大肠杆菌病等革兰氏阴性疾病有一定的影响,TLR4基因表达量的下调与F18大肠杆菌的抗性具有一定程度的关系。 展开更多
关键词 TLR4基因 F18大肠杆菌 real-time PCR 表达谱
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