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ApcD is required for state transition but not involved in blue-light induced quenching in the cyanobacterium Anabaena ***7120

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Chinese Science Bulletin 2008年第21期53卷 3422-3424页

作者： DONG chunxia zhao JinDong State Key Lab of Protein and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

Pbycobilisomes(PBS) are able to transfer absorbed energy to photosystem I and Ⅱ,and the distribution of light energy between two photosystems is regulated by state *** this study we show that energy transfer from PBS to photosystem I(PSI) requires *** were unable to perform state transitions in the absence of *** apcD mutant grows more slowly in light mainly absorbed by PBS,indicating that ApcD-dependent energy transfer to PSI is required for optimal growth under this *** apcD mutant showed normal blue-light induced quenching,suggesting that ApcD is not required for this process and state transitions are independent of blue-light induced *** nitrogen fixing condition,the growth rates of the wild type and the mutant were the same,indicating that energy transfer from PBS to PSI in heterocysts was not required for nitrogen fixation.

关键词：蓝藻细菌光合体系藻胆蛋白体状态转移

New Layered SOA-Based Architecture for Multi-robots Cooperative Online SLAM

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Chinese Journal of Electronics 2014年第1期23卷 25-30页

作者： CAI Yunfei TANG Zhenmin zhao chunxia Institute of Pattern Recognition and Artificial Intelligence Nanjing University of Science and Technology

A new layered multi-robots architecture for cooperative online simultaneous localization and mapping based on Service-oriented architecture(SOA) is proposed. This architecture is constructed by the concepts of service-oriented and loosely coupled center *** methods make robots' underlying function realization be transparent in cooperation and avoid the impact affected by robot heterogeneous characteristics, which will be beneficial to the system construction, expansion, restructuring and maintenance. All data packages follow the SOA unified data format, which can avoid the impact affected by sensor heterogeneous characteristics. The point to point serving model reduces the path of data transmission which can improve the timeliness of the system. All of these features can satisfy the requirements of multi-robots cooperative online SLAM. The simulation results show the feasibility, applicability and practicability of this architecture.

关键词： Service-oriented architecture(SOA) Multi-robot cooperative online SLAM(MRCO-SLAM) Loosely coupled

A new approach of formation navigation derived from multi-robots cooperative online FastSLAM

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控制理论与应用（英文版） 2012年第4期10卷 451-457页

作者： Yunfei CAI Zhenmin TANG chunxia zhao Institute of Pattern Recognition and Artificial Intelligence Nanjing University of Science and Technology

A new formation navigation approach derived from multi-robots cooperative online FastSLAM is proposed. In this approach, the leader and follower robots are defined. The posteriori estimation of the leader robot state is treated as a relative reference for all follower robots to correct their state priori estimations. The control volume of individual follower will be achieved from the results of the corrected estimation. All robots are observed as landmarks with known associations by the others and are considered in their landmarks updating. By the method, the errors of the robot posterior estimations are reduced and the formation is well kept. The simulation and physical experiment results show that the multi-robots relative localization accuracy is improved and the formation navigation control is more stable and efficient than normal leader-following strategy. The algorithm is easy in implementation.

关键词： Multi-robots Formation navigation FastSLAM

Studies and Properties of Ceramics with High Thermal Conductivity

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Journal of Rare Earths 2006年第Z1期24卷 189-192页

作者： Chen Guangle Fan Shigang zhao chunxia Wang Kun Xia Shuqin Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China

The sintering technology of the AlN ceramics power were discussed. It is discussed that the compound sintering aids is consistent with the enhancement of the the thermal conductivity of AlN ceramics, and sintering technics is helped to the improvement of density. It is analyzed how to sinter machinable AlN ceramics with high thermal conductivity. And the microstructure of compound ceramics based on AlN was studied.

关键词： sintering aids hot-pressed high thermal conductivity machinable composite ceramics

Preparation and Characteristic of Glass-Ceramics with Super Low Thermal Expansion Coefficient

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Journal of Rare Earths 2006年第Z1期24卷 119-121页

作者： zhao chunxia Fan Shigang Chen Guangle Jiang Hui Wang Shengjun Wang Kun Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China

The preparation technics of glass-ceramics with super low coefficient of thermal expansion containing β-quartz solid solution as a main crystal phase based on the glass in the system Li2O-Al2O3-SiO2 was introduced. The composition of base glass, technics of melting and heat treatment effecting on characteristic of glass-ceramics was described. Specimens were prepared by melting, anneal and controlled two steps heat treatment. Crystal phase, microstructure and elementary distributing were studied by using XRD, SEM and EDS respectively. Prepared specimens show excellent transparency and super low thermal expansion coefficient of 2×10-8 ·K-1, which reaches international advanced level.

关键词： low thermal expansion Li2O-Al2O3-SiO2 transparent glass-ceramics

Emotional and Behavioral Problems of Left-Behind Children in Impoverished Rural China:A Comparative Cross-Sectional Study of First Grade Junior High School

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International Journal of Mental Health Promotion 2021年第1期23卷 1-13页

作者： Yuming Zhou chunxia zhao Fan He Xiaobo Tian Yi Zheng Jing Sun Beijing Anding Hospital Capital Medical UniversityThe National Clinical Research Center for Mental DisordersBeijing Key Laboratory of Mental DisordersBeijing Institute for Brain DisordersBeijing100088China United Nations Children’s Fund(UNICEF China Office) Beijing100600China School of Medicine Griffith UniversityQueensland4222Australia

Objective:To investigate the prevalence of emotional and behavioral problems and related factors of left-behind children in impoverished rural China(mainly in thefirst grade of junior high school).Methods:A cross-sectional survey of rural households in 27 poverty-stricken counties in 12 provinces across China was conducted using the Strengths and Difficulties Questionnaire(SDQ).Results:The prevalence of emotional and behavioral problems in left-behind children was 11.7%,and that of non-left-behind children was 8.9%.There was statistical difference between the two groups(P<0.01).There are no differences between the two groups in terms of the various factors of *** incidence of insomnia in the left-behind group was 58.3%,which was higher than that in the non-left-behind group 50.9%(P<0.01);loneliness(62.1%vs.51.8%,P<0.01);running away from home(23.1%vs.18.8%,P<0.01),and self-injury behavior(16.8%vs.12.2%,P<0.01).Left-behind children are more likely to have negative psychological feelings including insomnia,loneliness,self-injury,and run away from *** also experienced more bullying including maliciously teased by peers,intentionally excluded or isolated,physically threatened or *** of these factors are associated with their abnormal emotional and behavioural ***:The incidence of emotional and behavioral problems of left-behind children in rural areas in poverty-stricken areas is significantly higher than that of non-left-behind children;Logistic regression analysis showed that bullying behavior and abnormal psychological characteristics are significantly associated with left-behind adolescents abnormal emotional and behavioral development.

关键词： Rural areas left-behind children emotional and behavioral problems incidence related factors

High-performance fiber strain sensor of carbon nanotube/thermoplastic polyurethane@styrene butadiene styrene with a double percolated structure

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Frontiers of Materials Science 2022年第1期16卷 99-110页

作者： Dong XIANG Libing LIU Xiaoyu CHEN Yuanpeng WU Menghan WANG Jie ZHANG chunxia zhao Hui LI Zhenyu LI Ping WANG Yuntao LI School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China College of Materials Science and Engineering Chongqing UniversityChongqing 400030China School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China The Center of Functional Materials for Working Fluids of Oil and Gas Field Southwest Petroleum UniversityChengdu 610500China

In this work,a high-performance fiber strain sensor is fabricated by constructing a double percolated structure,consisting of carbon nanotube(CNT)/thermoplastic polyurethane(TPU)continuous phase and styrene butadiene styrene(SBS)phase,incompatible with TPU(CNT/TPU@SBS).Compared with other similar fiber strain sensor systems without double percolated structure,the CNT/TPU@SBS sensor achieves a lower percolation threshold(0.38 wt.%)and higher electrical *** conductivity of 1%-CNT/TPU@SBS(4.12×10^(-3) S·m^(-1))is two orders of magnitude higher than that of 1%-CNT/TPU(3.17×10^(-5) S·m^(-1))at the same CNT loading of 1 wt.%.Due to double percolated structure,the 1%-CNT/TPU@SBS sensor exhibits a wide strain detection range(0.2%-100%)and an ultra-high sensitivity(maximum gauge factor(GF)is 32411 at 100%strain).Besides,the 1%-CNT/TPU@SBS sensor shows a high linearity(R^(2)=0.97)at 0%-20%strain,relatively fast response time(214 ms),and stability(500 loading/unloading cycles).The designed sensor can efficiently monitor physiological signals and movements and identify load distribution after being woven into a sensor array,showing broad application prospects in wearable electronics.

关键词： double percolated structure strain sensor fiber carbon nanotube nanocomposite

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基于多任务混合噪声分布模型表示的视频跟踪

计算机工程与应用 2015年第13期51卷 15-24页

作者：亚森江.木沙赵春霞南京理工大学计算机科学与工程学院南京210094 新疆大学机械工程学院乌鲁木齐830046

视觉跟踪中,目标信息是不确定的非线性变化过程。随时间和空间而变化的复杂动态数据中学习出较为精确的目标模板并用它来线性表示候选样本外观模型,从而使跟踪器较好地适应跟踪作业中内在或外在因素所引起的目标外观变化是视觉目标跟踪... 详细信息

视觉跟踪中,目标信息是不确定的非线性变化过程。随时间和空间而变化的复杂动态数据中学习出较为精确的目标模板并用它来线性表示候选样本外观模型,从而使跟踪器较好地适应跟踪作业中内在或外在因素所引起的目标外观变化是视觉目标跟踪研究的重点。提出一种新颖的多任务混合噪声分布模型表示的视频跟踪算法,将候选样本外观模型假设为由一组目标模板和最小重构误差组成的多任务线性回归问题。利用经典的增量主成分分析法从高维数据中学习出一组低维子空间基向量(模板正样本),并在线实时采样一些特殊的负样本加以扩充目标模板,再利用扩充后的新模板和独立同分布的高斯-拉普拉斯混合噪声来线性拟合当前时刻的候选目标外观模型,最后计算候选样本和真实目标之间的最大似然度,从而准确捕捉当前时刻的真实目标。在一些公认测试视频上的实验结果表明,该算法将能够在线学习较为精准的目标模板并定期更新目标在不同状态时的特殊信息,使得跟踪器始终保持最佳的状态,从而良好地适应不断发生变化的视觉信息(姿态、光照、遮挡、尺度、背景扰乱及运动模糊等),表现出更好的鲁棒性能。

关键词：目标跟踪多任务增量子空间学习实时字典扩充

FMO3-TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection fraction:evidence from an Asian population

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Frontiers of Medicine 2022年第2期16卷 295-305页

作者： Haoran Wei Mingming zhao Man Huang Chenze Li Jianing Gao Ting Yu Qi Zhang Xiaoqing Shen Liang Ji Li Ni chunxia zhao Zeneng Wang Erdan Dong Lemin Zheng Dao Wen Wang Division of Cardiology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science&Technology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological DisordersWuhan 430030China Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesBeijing Key Laboratory of Cardiovascular Receptors ResearchBeijing 100191China The Institute of Cardiovascular Sciences Peking UniversityKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationBeijing 100191China Department of Cardiology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Cellular and Molecular Medicine Lerner Research InstituteCleveland ClinicClevelandOH 44195USA

The association among plasma trimethylamine-N-oxide(TMAO),FMO3 polymorphisms,and chronic heart failure(CHF)remains to be *** is a microbiota-dependent metabolite from dietary choline and carnitine.A prospective study was performed including 955 consecutively diagnosed CHF patients with reduced ejection fraction,with the longest follow-up of 7 *** concentrations of plasma TMAO and its precursors,namely,choline and carnitine,were determined by liquid chromatography-mass spectrometry,and the FMO3 E158K polymorphisms(rs2266782)were *** top tertile of plasma TMAO was associated with a significant increment in hazard ratio(HR)for the composite outcome of cardiovascular death or heart transplantation(HR=1.47,95%CI=1.13-1.91,P=0.004)compared with the lowest *** adjustments of the potential confounders,higher TMAO could still be used to predict the risk of the primary endpoint(adjusted HR=1.33,95%CI=1.01-1.74,P=0.039).This result was also obtained after further adjustment for carnitine(adjusted HR=1.33,95%CI=1.01-1.74,P=0.039).The FM03 rs2266782 polymorphism was associated with the plasma TMAO concentrations in our cohort,and lower TMAO levels were found in the ***,higher plasma TMAO levels indicated increased risk of the composite outcome of cardiovascular death or heart transplantation independent of potential confounders,and the FMO3 AA-genotype in rs2266782 was related to lower plasma TMAO levels.

关键词： chronic heart failure trimethylamine-N-oxide flavin monooxygenase 3 single nucleotide polymorphism