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部分线性变系数模型中误差方差的估计(英文)

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应用数学 2008年第2期21卷 378-383页

作者：魏传华吴喜之中央民族大学理学院统计学系北京100081 中国人民大学应用统计科学研究中心

作为部分线性模型与变系数模型的推广,部分线性变系数模型是一类在建模中应用非常广泛的模型.本文基于Profile最小二乘方法给出了模型中误差方差的估计并证明了该估计的渐近正态性.最后通过数值模拟验证了我们所提估计方法的有效性.

关键词：渐近正态性误差方差部分线性变系数模型 Profile最小二乘估计

Dual-curvilinear beam enabled tunable manipulation of high-and low-refractive-index particles

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Photonics Research 2024年第7期12卷 1427-1436页

作者： ZHENG YUAN CHENCHEN ZHANG YUAN GAO WENxiANG YAN xiAN LONG zhi-CHENG REN xi-LIN WANG JIANPING DING HUI-TIAN WANG National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics Nanjing 210093China

We present an innovative approach for the simultaneous agile manipulation of high-refractive-index(HRI) and low-refractive-index(LRI) particles. Our method involves introducing a dual-curvilinear optical vortex beam(DC-OVB) generated by superimposing a pair of curved beams: HRI and LRI particles are controlled by the bright curve and the dark channel between the two curves, respectively. The proposed DC-OVB provides customizable motion paths and velocities for both LRI and HRI particles. Each curve of the DC-OVB can support a distinct orbital flow density(OFD), enabling the application of torques to HRI and LRI particles, guiding them to orbit along specified trajectories and prompting them to execute various curvilinear motions simultaneously,including curvilinear movement, revolution, and rotation.

关键词： tunable refractive beam

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-zhi Zang Qing-Wei Dong Guang-xi Wan xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Bioengineered skin organoids:from development to applications

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Military Medical Research 2024年第3期11卷 449-466页

作者： Zi-Xuan Hong Shun-Tian Zhu Hao Li Jing-zhi Luo Yu Yang Yang An xi Wang Kai Wang Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Department of Hepatopancreatobiliary Surgery the Third Affiliated Hospital of Soochow UniversityChangzhou 213000JiangsuChina Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China State Key Laboratory of Cardiovascular Disease Fuwai HospitalBeijing 100037China Beijing Key Laboratory of Metabolic Disorder Related Cardiovascular Disease Capital Medical UniversityBeijing 100050China

Signifcant advancements have been made in recent years in the development of highly sophisticated skin *** as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical *** inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic *** review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with ***,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic *** review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations.

关键词： Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine

SENP3 Promotes Mantle Cell Lymphoma Development through Regulating Wnt10a Expression

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Current Medical Science 2024年第1期44卷 134-143页

作者： Yan-ni MA Yun-ding ZOU zhi-long LIU Gui-xian wu Yuan-ze ZHOU Cheng-xin LUO xiang-tao HUANG Ming-ling xiE Shuang-nian XU xi LI Department of Hematology Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Department of Hematology the Third Affiliated Hospital(Daping Hospital)Third Military Medical University(Army Medical University)Chongqing 400042China

Objective SUMO-specific protease 3(SENP3),a member of the SUMO-specific protease family,reverses the SUMOylation of SUMO-2/3 *** of SENP3 has been proven to be involved in the development of various ***,its role in mantle cell lymphoma(MCL),a highly aggressive lymphoma,remains *** study was aimed to elucidate the effect of SENP3 in *** The expression of SENP3 in MCL cells and tissue samples was detected by RT-qPCR,Western blotting or *** cells with stable SENP3 knockdown were constructed using short hairpin *** proliferation was assessed by CCK-8 assay,and cell apoptosis was determined by flow *** sequencing(mRNA-seq)was used to investigate the underlying mechanism of SENP3 knockdown on MCL development.A xenograft nude mouse model was established to evaluate the effect of SENP3 on MCL growth in *** SENP3 was upregulated in MCL patient samples and *** of SENP3 in MCL cells inhibited cell proliferation and promoted cell ***,the canonical Wnt signaling pathway and the expression of Wnt10a were suppressed after SENP3 ***,the growth of MCL cells in vivo was significantly inhibited after SENP3 knockdown in a xenograft nude mouse *** SENP3 participants in the development of MCL and may serve as a therapeutic target for MCL.

关键词： mantle cell lymphoma SENP3 cell proliferation apoptosis

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese Journal of Natural Medicines 2024年第02期 161-170页

作者： SUN Zeshi LIN Shan wu zhi-Li DONG Hong-Yuan XU xi-Ke LI Hui-Liang WANG Jinxin School of Pharmacy Second Military Medical University State Key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical Industry China State Institute of Pharmaceutical Industry

Our continued works on the chemical constituents of Ginkgo biloba(G. biloba) leaves has led to the isolation of two novel phenylbutenoids(1, 2), along with five previously unidentified terpene glycosides(3-7). Among them, compounds 1 and 2 represent unique(Z)-phenylbutenoids, 3-6 are megastigmane glycosides, and 7 is identified as a rare bilobanone glycoside(Fig. 1). This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from G. biloba. The chemical structures of these compounds were elucidated through extensive spectroscopic analysis, including HR-ESI-MS and various 1D and 2D NMR experiments. Furthermore, the absolute configurations of these molecules were determined using Mosher's method, ECD experiments, and Cu-Kα X-ray crystallographic analyses.

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Iso-propagation vortices with OAM-independent size and divergence toward future faster optical communications

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Advanced Photonics 2024年第3期6卷 51-59页

作者： Wenxiang Yan Zhaozhong Chen xian Long Yuan Gao Zheng Yuan zhi-Cheng Ren xi-Lin Wang Jianping Ding Hui-Tian Wang Nanjing University School of Physics National Laboratory of Solid State Microstructures Nanjing University Collaborative Innovation Center of Advanced Microstructures University of Glasgow James Watt School of Engineering Nanjing University Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics

Recognized in the 1990s, vortex beams' ability to carry orbital angular momentum(OAM) has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication. However, inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM, limiting vortex beams' applicability in areas such as spatial mode multiplexing communication, fiber-optic data transmission, and particle manipulation. These domains necessitate vortex beams with OAM-independent propagation *** introduce iso-propagation vortices(IPVs), vortex beams characterized by OAM-independent propagation behavior, achieved through precise radial index configuration of Laguerre–Gaussian beams. IPVs display notable transmission dynamics, including a reduced quality factor, resilience post-damage, and decreased and uniform modal scattering under atmospheric turbulence. Their distinctive attributes render IPVs valuable for potential applications in imaging, microscopy, optical communication, metrology, quantum information processing, and light–matter interactions. Notably, within optical communication, the case study suggests that the IPV basis, due to its OAM-independent propagation behavior, provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques, consequently augmenting information capacity.

关键词： orbital angular momentum optical communication structured light optical vortices

Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-zhi Xu Shi-Yu Zhang xin-Yi Pan Chang-Lin Lan Jie Ren xi-Chao Ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data

Tungsten pnictides for water electrolysis:advances and perspectives

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Tungsten 2024年第4期6卷 675-695页

作者： Xue Kang xi-Han Tan Ning Han Jian-Feng Hou Chen-Min Yao zhi-Jie Chen Bing-Jie Ni Department of Chemistry and Chemical Engineering Lyuliang University Department of Materials Engineering State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of Education Hubei Key Laboratory of Stomatology School & Hospital of Stomatology Wuhan University School of Civil and Environmental Engineering The University of New South Wales

Hydrogen fuel is recognized as a promising energy carrier for the sustainable development of global energy system and the green hydrogen production via water electrolysis attracts great *** development of cost-effective electrocatalysts for water electrolysis is important for enhancing green hydrogen production ***,tungsten pnictides(phosphides and nitrides) have emerged as promising catalysts for water electrolysis,and efficient tungsten pnictide-based catalysts with different nanostructures,compositions,and surface chemical properties have been *** this review,recent progress in the design of tungsten pnictide-based electrocatalysts for water electrolysis is comprehensively *** synthesis of tungsten pnictide-based electrocatalysts are discussed ***,current achievements in developing efficient tungsten pnictide electrocatalysts for water electrolysis are detailed,and four key catalyst design strategies(i.e.,nanostructure control,heteroatom doping,defect engineering,and heterostructure design) are *** physicochemical properties-catalytic performance relationship of tungsten pnictide-based electrocatalysts is also *** last,perspectives in this field are put forward for guiding further research on the design and application of high-performance tungsten pnictide-based electrocatalysts.

关键词： Electrocatalysts Hydrogen evolution reaction Oxygen evolution reaction Tungsten nitrides Tungsten phosphides