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Exponential-Poisson Parameters Estimation in Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年

作者： Meng chen wang-xue chen Rui YANG Ya-wen ZHOU Department of Mathematics and Statistics Jishou University

In this article, the maximum likelihood estimators (MLEs) of the scale and shape parameters βandλfrom the Exponential-Poisson distribution will be considered in moving extremes ranked set sampling(MERSS). These MLEs will be compared in terms of asymptotic efficiencies. The numerical results show that these MLEs in MERSS can be real competitors against those in simple random sampling.

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Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-Lin Xiong Ji-Rong Mao Shuang-Nan Zhang wang-chen xue Chao Zheng Jia-Cong Liu Zhen Zhang Xi-Lu wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai Xin-Qiao Li Wen-Xi Peng Wen-Jun Tan chen-Wei wang Xiang-Yang Wen Yue wang Shuo Xiao Fan Zhang Peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

基于超分辨成像增强对拟南芥内质网动态变化的研究

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生物技术通报 2024年第4期40卷 67-76页

作者：张以恒刘家正王雪晨孙政哲薛雅郡汪沛韩华郑宏伟李晓娟北京林业大学理学院林木资源高效生产全国重点实验室北京100083 北京林业大学生物科学与技术学院林木、花卉遗传育种教育部重点实验室北京100083 北京林业大学生物科学与技术学院林木育种与生态修复国家工程研究中心北京100083 中国科学院自动化研究所多模态人工智能系统全国重点实验室北京100190 中国科学院大学未来技术学院北京100049 脑认知功能图谱与类脑智能交叉研究平台北京101499 华中科技大学计算机科学与技术学院武汉430074 中国科学院新疆生态与地理研究所乌鲁木齐830001

【目的】为了解决在植物细胞内质网的研究中,成像速度与成像分辨率难以同时满足准确识别精细结构和动态变化的瓶颈问题。【方法】使用结构光照明显微成像技术,对拟南芥活体材料中的内质网进行超分辨实时成像,并优化了自监督去噪框架(Bli... 详细信息

【目的】为了解决在植物细胞内质网的研究中,成像速度与成像分辨率难以同时满足准确识别精细结构和动态变化的瓶颈问题。【方法】使用结构光照明显微成像技术,对拟南芥活体材料中的内质网进行超分辨实时成像,并优化了自监督去噪框架(Blind2Unblind),以进一步提升快速显微成像的信噪比。【结果】建立了对时间序列成像中内质网结构进行定量分析的方法,并通过对环境胁迫下内质网结构动态变化的追踪进一步验证了方法的有效性。此外,各类参数的相关性分析显示管状内质网的面积和长度与生长端和三叉点的数量显著正相关,而内质网池和整体流的面积与管的面积和长度显著负相关。【结论】优化的自监督去噪框架提升了植物活细胞中结构光照明显微图像的信噪比,实现了管状内质网、内质网池、整体流、生长端和节点等复杂结构和动态的量化,各结构间存在复杂相关性。

关键词：拟南芥内质网动态超分辨率成像成像增强量化分析

Best Linear Unbiased Estimators of Location and Scale Ranked Set Parameters under Moving Extremes Sampling Design

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 222-231页

作者： Yan-fei DONG wang-xue chen Min-yu XIE Department of Mathematics and Statistics Jishou UniversityJishou 416000China Department of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

In the current paper,the best linear unbiased estimators(BLUEs)of location and scale parameters from location-scale family will be respectively proposed in cases when one parameter is known and when both are unknown under moving extremes ranked set sampling(MERSS).Explicit mathematical expressions of these estimators and their variances are *** relative efficiencies with respect to the minimum variance unbiased estimators(MVUEs)under simple random sampling(SRS)are compared for the cases of some usual *** numerical results show that the BLUEs under MERSS are significantly more efficient than the MVUEs under SRS.

关键词： location-scale parameters best linear unbiased estimator moving extremes ranked set sampling

Maximum Likelihood Estimator of the Location Parameter under Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 101-108页

作者： wang-xue chen Chun-xian LONG Rui YANG Dong-sen YAO Department of Mathematics and Statistics Jishou UniversityJishou 416000China

Cost effective sampling design is a problem of major concern in some experiments especially when the measurement of the characteristic of interest is costly or painful or time *** the current paper,a modification of ranked set sampling(RSS)called moving extremes RSS(MERSS)is considered for the estimation of the location parameter for location family.A maximum likelihood estimator(MLE)of the location parameter for this family is studied and its properties are *** prove that the MLE is an equivariant estimator under location *** order to give more insight into the performance of MERSS with respect to(w.r.t.)simple random sampling(SRS),the asymptotic efficiency of the MLE using MERSS *** using SRS is computed for some usual location *** relative results show that the MLE using MERSS can be real competitors to the MLE using SRS.

关键词： ranked set sampling moving extremes ranked set sampling maximum Likelihood estimator equivariant estimator fisher information number

Existence and Characteristics of Tonoplast-bound Protein Kinase in the Tip Cell of Maize Root

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Acta Botanica Sinica 2002年第6期44卷 661-666页

作者：陈硕陈珈王学臣中国农业大学生物学院

For understanding the function of tonoplast protein in plant cell signal pathway, we have identified an integral protein kinase activity from the highly purified tonoplast isolated from maize ( Zea mays L.) root by a new nonradioactive method in which a color labeled peptide was used as substrate. The protein kinase was Ca 2+ _dependent and CaM and phosphatidylserine_independent, like the calmodulin_like domain protein kinase (CDPK) in many plants. The optimal pH value and Ca 2+ concentration were 6.5 and 10 μmol/L, respectively. According to the optimal pH value and the effect of detergent, it could be inferred that the active site of this protein kinase is oriented toward the cytoplasm. Zn 2+ had no obvious effect on its activity, indicating that this protein kinase has no zinc_finger domain that exists in some mammalian protein kinases. At the same time, when tonoplast proteins were prephosphorylated in the presence of Ca 2+ and ATP, both the ATP_hydrolysis and the proton_transport activity of vacuolar H +_ATPase were stimulated. This stimulation could be reversed by an alkaline_phosphatase. These results indicate that a Ca 2+ _dependent protein kinase was located in the tonoplast, and a Ca 2+ _dependent phosphorylation, probably caused by this kinase, activated the vacuolar H +_ATPase activity. These results are helpful for further research on the function of CDPK in the course of signal transduction in plants.

关键词： protein kinase phosphorylation H +_ATPase tonoplast maize

Glycemic variability in insulin treated type 2 diabetes with well-controlled hemoglobin Alc and its response to further treatment with acarbose

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Chinese Medical Journal 2011年第1期124卷 144-147页

作者： SU Jian-bin wang xue-qin chen Jin-feng WU Gang JIN Yan Department of Endocrinology Second Affiliated Hospital of Nantong University Nantong Jiangsu 226001 China

Background Glycemic variability, an HbAlc-independent risk factor, has more deleterious effects than sustained hyperglycemia in the development of diabetic complications. This study analyzed the characteristics of glycemic variability in type 2 diabetes mellitus （T2DM） with HbAlc 〈6.5% in duration of twice daily premixed insulin treatment and the effect of further treatment with acarbose. Methods Eighty-six T2DM patients who used premixed insulin analogue （insulin aspart 30） twice daily and had HbAlc 〈6.5% and 20 controlled subjects with normal glucose regulation （NGR） were monitored using the continuous glucose monitoring （CGM） system. The mean amplitude of glycemic excursions （MAGE）, mean of daily differences （MODD） were used for assessing intra-day, inter-day glycemic variability. Hypoglycemia was defined as glucose level 〈3.9 mmol/L for at least 15 minutes in CGM. According to reference values of MAGE, T2DM patients were classified into two groups： Iow-MAGE group with MAGE 〈3.4 mmol/L （L-MAGE） and high-MAGE group with MAGE 〉3.4 mmol/L （H-MAGE）. H-MAGE group received further treatment with acarbose for 2 weeks and was monitored a second time with CGM system. Results After first CGM, L-MAGE group had 41 cases, and H-MAGE group had 45 cases. The MAGE and MODD of T2DM group were all higher than those of subjects with NGR （P 〈0.01）. Twenty-four percent （n=11） in H-MAGE group had a total of 13 hypoglycemic events, 10 of the 13 events occurred at night, meanwhile 5% （n=-2） in L-MAGE group had a total of 2 hypoglycemic events, which also occurred at night （hypoglycemic events： 24% vs. 5%, X2=6.40, P 〈0.01）. MAGE value was correlated with hypoglycemia value and 2-hour postprandial plasma glucose value （r=-0.32 and 0.26, respectively, P 〈0.05）. After further acarbose therapy and secondly CGM, MAGE and MODD values in H-MAGE group were all significantly decreased （40%, P 〈0.01, and 15%, P 〈0.05, respectively）, but remained higher than in the subjects with NGR （P 〈0.05）; 2%

关键词： glycemic variability type 2 diabetes HbAl c insulin treatment acarbose continuous glucose monitoring

Effect of ceramic work rolls on surface roughness of rolled SUS304 ultra-thin strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1704-1718页

作者： Peng-cheng Li Tao wang chen-chen Zhao Qi Liu Qing-xue Huang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip *** order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultra-thin strip,ABAQUS finite element model calculation,3D laser profilometry,and other methods were adopted based on the physical characteristics of Si_(3)N_(4) ceramic roll and 9Cr2MoV steel roll,like anti-flattening performance and oil *** surface morphology and roughness of SUS304 ultra-thin strip rolled by different material work rolls under oil lubrication conditions were *** results showed that under the rolling force of 10 kN,the maximum flattening amount of Si_(3)N_(4) ceramic roll was reduced by 35.14%compared to that of 9Cr2MoV steel *** reduction rate of SUS304 ultra-thin strip rolled by ceramic roll was 34.19%,while that rolled by steel roll was only 22%;Si_(3)N_(4) ceramic roll can further increase the number of alternating convex peaks and concave valleys in the rolled thin strip,reduce the profile steepness,reduce surface roughness,and enhance the planarization effect of surface micro-convex bodies,with improving surface quality and surface ***,the mechanism of Si_(3)N_(4) ceramic roll significantly improving the surface roughness of rolled SUS304 ultra-thin strip was proposed.

关键词： Ceramic work roll-Steel roll SUS304 ultra-thin strip Reduction Surface roughness

Ant-nest-inspired porous structure for MXene composites with high-performance energy-storage and actuating multifunctions

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Nano Research 2024年第7期17卷 6673-6685页

作者： Yi wang Guanfeng xue Zhiling Luo Wei Zhang Luzhuo chen Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials College of Physics and EnergyFujian Normal UniversityFuzhou 350117China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering Fuzhou 350117China

Integrating energy-storage devices(supercapacitors)and shape-deformation devices(actuators)advances the miniaturization and multifunctional development of soft ***,soft robots necessitate supercapacitors with high energy-storage performance and actuators with excellent actuation ***,inspired by ant nests,we present a porous structure fabricated by MXene-graphene-methylcellulose(M-GMC)composite,which overcomes the self-stacking of MXene nanosheets and offers a larger specific surface *** porous structure provides more channels and active sites for electrolyte ions,resulting in high energy storage *** areal capacitance of the M-GMC electrode reaches up to 787.9 mF·cm^(−2),significantly superior to that of the pristine MXene electrode(449.1 mF·cm^(−2)).Moreover,the M-GMC/polyethylene bilayer composites with energy storage and multi-responsive actuation functions are *** M-GMC is used as the electrode and the polyethylene is used as the encapsulation layer of the quasi-solid-state ***,the actuators fabricated by the bilayer composites can be driven by light or low voltage(≤9 V).The maximum bending curvature is up to 5.11 cm^(−1).Finally,a smart gripper and a fully encapsulated smart integrated circuit based on the M-GMC/polyethylene are *** smart gripper enables programmable control with multi-stage *** applications realize the intelligence and miniaturization of soft *** ant-nest-inspired M-GMC composites would provide a promising development strategy for soft robots and smart integrated devices.

关键词： MXene graphene ant nest supercapacitor actuator multi-functional