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Linkage Map Construction and Quantitative Trait Loci Analysis for Bolting Based on a Double Haploid Population of Brassica rapa

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Journal of Integrative Plant Biology 2007年第5期49卷 664-671页

作者： Xu Yang Yang-jun Yu Feng-Lan Zhang Zhi-Rong Zou Xiu-Yun zhao De-Shuang Zhang Jia-Bing Xu College of Horticulture Northwest A & F University Yangling 712100 China National Engineering Research Center for Vegetables Beijing 100089 China

Early bolting of Chinese cabbage （Brassica rapa L.） during spring cultivation often has detrimental effects on the yield and quality of the harvested products. Breeding late bolting varieties is a major objective of Chinese cabbage breeding programs. In order to analyze the genetic basis of bolting traits, a genetic map of B. rapa was constructed based on amplified fragment-length poiymorphism （AFLP）, sequence-related amplified poiymorphism （SRAP）, simple sequence repeat （SSR）, random amplification of polymorphic DNA （RAPD）, and isozyme markers. Marker analysis was carried out on 81 double haploid （DH） lines obtained by microspore culture from F1 progeny of two homozygous parents： B. rapa L. ssp. pekinensis （BY）（an extra-early bolting Chinese cabbage line） and B. rapa L. ssp. rapifera （MM）（an extra-late bolting European turnip line）. A total of 326 markers including 130 AFLPs, 123 SRAPs, 16 SSRs, 43 RAPDs and 14 isozymes were used to construct a linkage map with 10 linkage groups covering 882 cM with an average distance of 2.71 cM between loci. The bolting trait of each DH line was evaluated by the bolting index under controlled conditions. Quantitative trait loci （QTL） analysis was conducted using multiple QTL model mapping with MapQTL5.0 software. Eight QTLs controlling bolting resistance were identified. These QTLs, accounting for 14.1% to 25.2% of the phenotypic variation with positive additive effects, were distributed into three linkage groups. These results provide useful information for molecular marker-assisted selection of late bolting traits in Chinese cabbage breeding programs.

关键词： bolting index Chinese cabbage doubled haploid population genetic map quantitative trait Ioc

Evaluation of the effect of myocardial perfusion after percutaneous coronary intervention in coronary artery disease by using intracoronary myocardial contrast echocardiography and two other angiographic techniques

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Frontiers of Medicine 2007年第1期1卷 62-67页

作者： WANG Hong HUANG Lan JIN jun SONG Yaoming GENG zhaohua YU Xuejun QIN jun zhao Gang GAO Yunhua LIU Zheng YANG Li Department of Cardiology Xingqiao HosipitalThird Military Medical UniversityChongqing 400037China Department of Ultrasoundy Xingqiao HosipitalThird Military Medical UniversityChongqing 400037China

Detection of abnormal myocardial perfusion is crucial to the prognosis of patients with coronary artery disease(CAD)after they have undergone percutaneous coronary intervention(PCI).The objective of this study is to evaluate the effect of myocardial perfusion by three different methods—intra-coronary myocardial contrast echocardiography(ICMCE),corrected thrombolysis in myocardial infarction frame count(CTFC),and coronary blood flow velocity(BFV)—and to determine the value of these different methods in the evaluation of the effect of myocardial perfusion *** the study sixty-eight patients were divided into four groups based on selective coronary angiography results:group A(normal coronary artery),group B(75%–95%coronary artery stenosis),group C(coronary artery stenosis>95%)and group D(acute total coronary occlusion).The effect of myocardial reperfusion was evaluated using the above mentioned three methods 15 min after ***-MCE was also performed before PCI in group *** quantitative parameters of MCE involved:contrast peak intensity,time to peak intensity and area under the curve,representing myocardial blood volume,reperfusion velocity and myocardial blood flow,*** difference was found in CTFC between the coronary artery stenosis group and the normal *** was slower in group D than in group A(P<0.05).The myocardial blood volume and the myocardial blood flow of the IC-MCE quantitative parameters were markedly lower in group C compared with those in group A(P<0.05),and there were significant differences in the three MCE parameters between group D and group A(P<0.05).For those patients with acute or total occlusion,the levels of myocardial perfusion before and after PCI were similar,as determined by IC-MCE and visually analyzed from 61 segments(P<0.05).Quantitative IC-MCE evaluation of myocardial reperfusion is more accurate than with the other two ***,with qualitative IC-MCE the level of myocardial reperfusion can be viewed di

关键词： percutaneous coronary intervention coronary artery disease intra-coronary myocardial echocardiography corrected thrombolysis in myocardial infarction frame count blood flow velocity

Composition of phenolic compounds in wastewater from the fixed-bed gasification of Baishihu coal

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International Journal of Coal Science & Technology 2021年第6期8卷 1461-1467页

作者： Yuan zhao Beijing Research Institute of Coal Chemistry China Coal Research InstituteBeijing 100013China State Key Laboratory of Coal Mining and Clean Utilization Beijing 100013China

Crude phenols extracted using organic solvent from the wastewater of a typical fixed-bed gasification process was used as a raw material,and the distillation range was *** wide and narrow fractions of the raw material derived from distillation range analysis were cut using a real boiling point distillation *** phenolic compounds in the different fractions were then qualitatively and quantitatively analyzed by gas chromatography after derivatization *** yield of the<290℃fraction was 68.50%(mass fraction).A total of 33 effective phenolic compounds were identified in this fraction,and the percentage of identified phenols was nearly 80%.The contents of eight phenolic compounds were high,with phenol being the most abundant(26.34%)followed by catechol(13.44%).The contents of the remaining six abundant phenols ranged from 4%to 8%.The sum of the contents of m-cresol and p-cresol exceeded 12%,and the content of 5-indenol was nearly 8%.The yield of the fraction rich in low-grade phenols(<230℃)was 35.40%.The content of phenol in this fraction was more than 40%,the total content of cresol was over 23%,and the total content of m-cresol and p-cresol was nearly 20%.At room temperature,the 235-245℃and 245-260℃fractions were white crystals in which the catechol content was approximately 50%,and the 5-indenol content was more than 10%.The contents of these two high-value-added phenolic compounds are low in typical coal tar,making them difficult to ***,due to their strong polarity and good water solubility,catechol and 5-indenol are enriched in gasification wastewater by water selection,allowing their further extraction.

关键词： Gasification wastewater Phenolic compounds Derivatization pretreatment Gas chromatography

Parameter comparison of white matter diffusion tensor imaging （DTI） in rhesus macaques （Macaca mulatta）

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Zoological Research 2014年第3期35卷 182-185页

作者： Yin MO Fang CHAO Ming SONG Ci-Rong LIU Hui-Lang LIU Xi-ying QIAN Xu-Dong zhao Department of Medical Imaging the First Affiliated Hospital of Kunming Medical University Kunming 650032 China National Laboratory of Pattern Recognition Institute of A utomation Chinese Academy of Sciences Beijing 1 O0190 China Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan province Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Department of Neurology the First Yunnan Provincial Hospital Kunming 650032 China Laboratory of Primate Neuroscience Institute of Biophysics Chinese Academy of Sciences Beo'ing 100101 China

In this study, we analyzed diffusion tensor imaging （DTI） results of brain white matter in rhesus macaques （Macaca mulatta） with four different parameter settings and found that the sequence A （b=1000 s/mm^2, spatial resolution=1.25 mm ×1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） and B （b=800 s/mm^2, spatial resolution= 1.25 mm× 1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） could accurately track coarse fibers. The fractional anisotropy （FA） derived from sequence C （b=1000s/mm^2, spatial resolution=0.55 mm×0.55 mm×2.5 mm, direction number=33, NSA=3） was too fuzzy to be used in tracking white matter fibers. By comparison, the high resolution and the FA with high contrast of gray matter and white matter derived from sequence D （b=800 s/mm^2, spatial resolution=1.0 mm×1.0 mm ×1.0 mm, numbers of direction=33, NSA=3） qualified in its application in tracking both thick and thin fibers, making it an optimal DTI setting for rhesus macaques.

关键词： DTI Whiter matter Rhesus macaque

Consensus of multi-vehicle cooperative attack with stochastic multi-hop time-varying delay and actuator fault

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Journal of Systems Engineering and Electronics 2021年第1期32卷 228-242页

作者： CAI Guangbin zhao Yushan zhao Yang HU Changhua College of Missile Engineering Rocket Force University of EngineeringXi’an 710025China School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China

A consensus-distributed fault-tolerant(CDFT)control law is proposed for a class of leader-following multi-vehicle cooperative attack(MVCA)systems in this *** particular,the switching communication topologies,stochastic multi-hop timevarying delays,and actuator faults are considered,which may lead to system performance degradation or on certain occasions even cause system ***,the estimator of actuator faults for the following vehicle is designed to identify the actuator faults under a fixed *** the CDFT control protocol and trajectory following error are derived by the relevant content of Lyapunov stability theory,the graph theory,and the matrix *** CDFT control protocol is proposed in the same manner,where a more realistic scenario is considered,in which the maximum trajectory following error and information on the switching topologies during the cooperative attack are ***,numerical simulation are carried out to indicate that the proposed distributed fault-tolerant(DFT)control law is effective.

关键词： leader-following multi-vehicle cooperative attack(MVCA) switching topology fault-tolerant control stochastic multi-hop time-varying delay stochastic actuator fault

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互注意力融合图像和点云数据的3D目标检测

光学精密工程 2021年第9期29卷 2247-2254页

作者：陈俊英白童垚赵亮西安建筑科技大学信息与控制工程学院陕西西安710055

为了利用图像信息辅助点云数据提高3D目标检测精度,需要解决图像特征空间和点云特征空间自适应对齐融合的问题。本文提出了一种多模态特征自适应融合的3D目标检测深度学习网络。首先,对点云数据体素化,基于体素内的点云特征学习体素特... 详细信息

为了利用图像信息辅助点云数据提高3D目标检测精度,需要解决图像特征空间和点云特征空间自适应对齐融合的问题。本文提出了一种多模态特征自适应融合的3D目标检测深度学习网络。首先,对点云数据体素化,基于体素内的点云特征学习体素特征表示,用3D稀疏卷积神经网络获取点云数据的特征,同时用ResNet神经网络提取图像特征。然后通过引入互注意力模块自适应对齐图像特征和点云特征,得到基于图像特征增强后的点云特征。最后在此特征基础上应用区域提案网络和分类回归多任务学习网络实现3D目标检测。在KITTI 3D目标检测数据集上的实验结果表明:在小汽车的简易、中等、困难三个不同检测难度等级上,平均检测精度分别为88.76%,77.63%和76.14%。该方法能够有效融合图像信息和点云信息,提高3D目标检测的准确率。

关键词： 3D目标检测深度学习点云数据图像数据注意力机制

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双剪统一强度理论下复合裂纹的研究

长安大学学报（自然科学版） 2005年第3期25卷 58-61页

作者：赵均海魏雪英长安大学建筑工程学院陕西西安710061

应用双剪统一强度理论,研究了复杂应力下Ⅰ、Ⅱ、Ⅲ型复合断裂问题,给出了包含反映材料拉压性能差异的参数α及反映中间主应力效应的参数b的双剪统一强度断裂因子,通过改变拉压性能差异系数和中间主应力作用效应系数,退化得到不同屈服... 详细信息

应用双剪统一强度理论,研究了复杂应力下Ⅰ、Ⅱ、Ⅲ型复合断裂问题,给出了包含反映材料拉压性能差异的参数α及反映中间主应力效应的参数b的双剪统一强度断裂因子,通过改变拉压性能差异系数和中间主应力作用效应系数,退化得到不同屈服准则和不同材料下的断裂因子。当取不同的参数时,该统一解退化为双剪应力屈服准则解、MohrCoulomb解、Tresca和Mises解。结果表明,该双剪统一强度断裂因子可以适应于各种不同材料和不同受力情况,能充分发挥材料潜力,有重要的工程应用价值。

关键词：结构工程双剪统一强度理论断裂准则断裂因子

Simple and cost-effective determination of ciprofloxacin hydrochloride by electrical micro-titration

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Chinese Chemical Letters 2017年第7期28卷 1406-1412页

作者： Xu-Zhi Zhang Meng-Shi Huang Qian-Qian Yang Dong-Sheng Ding jun zhao Wen-Rong Yang Ke-Ming Qu Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao National Laboratory for Marine Science and Technology College of Marine Sciences Shanghai Ocean University School of Life and Environmental Sciences Deakin University

By employing an electrical micro-titration system, in which a capacitively coupled contactless conductivity detector（C^4D） was used to monitor the reaction process in real time, herein a novel method for determining ciprofloxacin hydrochloride（CIPHCl） was developed for the first time. Mode 1： Standard CIPHCl solutions at different concentrations were loaded into reaction cells, respectively, and were titrated with standard Ag^＋. Upon the titration, the formation of a precipitate alters the number of ions in the solution, raising the change of conductivity, which was monitored by a special C-4 D to construct a titration curve. The endpoint of the titration was located from the peak of the curve. Between the elapsed time and the initial concentration of titrand, a linear relationship was established over the range of2.0–8.0 mmol/L. Mode 2： Standard Fe^3＋ took the place of Ag^＋, and was used as titrant to recognize ciprofloxacin contributed to the formation of complexation, which also resulting a change of solution conductivity. Under optimized conditions, a working range of 1.0–5.0 mmol/L CIPHCl was found. Because the reaction solutions were isolated from the working electrodes, this pioneer work shows significant simplicity and cost-effectiveness, by eliminating the requirements for detector exchange/renewal between different measurements, and by involving no auxiliary chemicals. Both of the two approaches were applied successfully to determine CIPHCl in tablet samples. And the results were in good agreement with those obtained by reference method.

关键词： Ciprofloxacin hydrochloride Determination Micro-titration Capacitively coupled contactless conductivity detector Pharmaceutical analysis

The Continuous Weakening of Ideology in the Construction of China-Saudi Arabia Relations:A Historical Review

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Asian Journal of Middle Eastern and Islamic Studies 2020年第4期14卷 554-566,I0006页

作者： Rui Wu jun zhao Middle East Studies Institute Shanghai International Studies UniversityShanghaiChina

In international politics,the formulation and implementation of foreign policy guided by ideology often impede the normal development of bilateral relations between state *** the founding of the People’s Republic of China,the relationships between China and Saudi Arabia have experienced twists and turns,which roughly reflect a relational evolution from the initial political opposition and lack of interaction to the current comprehensive strategic *** this process,a prominent feature is that the ideological interference has decreased with the strengthening of China-Saudi *** article explores the underlying causes behind this phenomenon by starting from the basic historical facts of ideological interference that changed from strong to weak in bilateral relationships between China and Saudi *** regard to the reasons for the weakening of ideology,this article holds that the change of the international distribution of power from one of bipolarity to multipolarity is the starting point and the main external political factor;the consideration of national interests is the essential factor;the pluralistic value orientation is another vital factor that continuously extends the tolerances of both sides’foreign *** factors are superimposed on each other and jointly weaken ideological considerations in China-Saudi *** should be noted that ideological interference has not completely *** specific times and events,it may still become an obstacle to the development of China-Saudi Arabia relations.

关键词： China Saudi Arabia China-Saudi Arabia relations ideology causes