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Journal of Reproduction and Contraception 2013年第1期24卷 38-44页

作者： Xiao-hong GUAN Yun FENG Xiao-wei LU Jian-quan CHEN Yi-juan SUN Hong-ying sha Reproductive Medical Center Ruijin Hospital Medical School of Shanghai Jiaotong University shanghai Transgenic Research Center Department of Neurosurgery Fudan University Huashan Hospital National Key Laboratory for Medical Neurobiology Fudan University

Objective To analyze the blastocyst formation and chromosome statuses of reconstructed embryos derived from human-goat interspecies somatic cell nuclear transfer （iSCNT）, exploring the development retardant factors. Methods Human specific point probes cep2, cep6, tel2 and 1.q1..2, 21.22.1. combining fluorescence in-situ hybridization （FISH） technology were used to test trophectoderm cells of blastocyst and blastomeres of development arrest nuclear transfer （NT） embryos. Results A total of 209 reconstructed embryos were recovered, and the rate of blastocyst formation was 3.8% （8/209）. FISH signals showed that chromosomal abnormalities were present in 2 blastocysts （2/8） and 1.6 development arrest embryos （1.6/201.. Conclusion The rate of blastocyst formation is low, and reconstituted embryos of development arrest showed extensive chromosome abnormalities, suggesting that a chromosomal mechanism may underlie their developmental arrest.

关键词： interspecies somatic cell nuclear transfer (iSCNT) preimplantation embryonicdevelopment fluorescence in-situ hybridization (FISH) chromosomal status

Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing Xu sha-sha Wang Da-chuan Xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1.p) where α+β=1.p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1.3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

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西双版纳热带季节雨林细根周转的研究

山地学报 2005年第4期23卷 4488-4494页

作者：房秋兰沙丽清中国科学院西双版纳热带植物园中国科学院西双版纳热带植物园云南昆明650223 中国科学院研究生院北京1.0039

研究了季节雨林0~20 cm土层中≤2 mm细根的生物量、分解量、死亡量、生长量和周转率,并比较了0~1. cm和1.~20 cm土层细根生物量的差异。结果表明:0~1. cm的细根生物量明显多于1.~20 cm的细根生物量;在0~20 cm土层中,季节雨林活细根和死... 详细信息

研究了季节雨林0~20 cm土层中≤2 mm细根的生物量、分解量、死亡量、生长量和周转率,并比较了0~1. cm和1.~20 cm土层细根生物量的差异。结果表明:0~1. cm的细根生物量明显多于1.~20 cm的细根生物量;在0~20 cm土层中,季节雨林活细根和死细根生物量分别为5 41. ***-2和707 ***-2;细根生物量的季节变化显著,其中活细根生物量的最大值出现在5月,最小值出现在8月;年分解量、年死亡量、年生长量和年周转率分别为391.***-2,1.061.***-2,3 776 ***-2和0.70 times.a-1.

关键词：西双版纳季节雨林细根生物量细根周转

Insight into the development of electrolytes for aqueous zinc metal batteries from alkaline to neutral

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Chinese Chemical Letters 2024年第2期35卷 232-241页

作者： An Duan sha Luo Wei Sun School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Aqueous zinc metal batteries are considered as promising candidates for next-generation electrochemical energy storage devices,especially for large-scale energy storage,due to the advantages of high-safety,high energy density and low *** the bridge connecting cathode and anode,electrolyte provides a realistic operating *** alkaline and neutral aqueous zinc metal batteries,issues associated with electrolyte and anode are still *** this review,we reveal the development and evolution of electrolytes for aqueous zinc metal batteries from alkaline to neutral via the description of fundamentals and challenges in terms of comparison and *** also elaborate the strategies in electrolytes regulation and highlight the basic roles and progresses in additives engineering.

关键词： Aqueous electrolytes Zinc metal batteries pH-dependent chemistry Electrolyte regulation Additives engineering

Spin-orbit torque effect in silicon-based sputtered Mn_(3)Sn film

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Chinese Physics B 2024年第10期33卷 394-399页

作者： sha Lu Dequan Meng Adnan Khan Ziao Wang Shiwei Chen Shiheng Liang School of Physics Hubei UniversityWuhan 430062China Key Laboratory for Intelligent Sensing System and Security of Ministry of Education Wuhan 430062China

Noncollinear antiferromagnet Mn_(3)Sn has shown remarkable efficiency in charge-spin conversion,a novel magnetic spin Hall effect,and a stable topological antiferromagnetic state,which has resulted in great interest from researchers in the field of spin-orbit *** research has primarily focused on the spin-orbit torque effect of epitaxially grown noncollinear antiferromagnet Mn_(3)Sn ***,this method is not suitable for large-scale industrial *** this study,amorphous Mn_(3)Sn films and Mn_(3)Sn/Py heterostructures were prepared using magnetron sputtering on silicon *** spin-torque ferromagnetic resonance measurement demonstrated that only the conventional spin-orbit torque effect generated by in-plane polarized spin currents existed in the Mn_(3)Sn/Py heterostructure,with a spin-orbit torque efficiency of ***,we prepared the perpendicular magnetized Mn_(3)Sn/CoTb heterostructure based on amorphous Mn_(3)Sn film,where the spin-orbit torque driven perpendicular magnetization switching was achieved with a lower critical switching current density(3.9×1.^(7)A/cm^(2))compared to Ta/CoTb *** research reveals the spin-orbit torque effect of amorphous Mn_(3)Sn films and establishes a foundation for further advancement in the practical application of Mn_(3)Sn materials in spintronic devices.

关键词： spintronics noncollinear antiferromagnetism spin-orbit torque

The Extended Hybrid Carrier-Based Multiple Access Technology for High Mobility Scenarios

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China Communications 2024年第1期21卷 53-68页

作者： Ge Song Xiaojie Fang Xuejun sha School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering *** this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless *** employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution *** implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is *** addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access *** proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility *** results have verified the feasibility and advantages of the proposed *** with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications.

关键词： extended hybrid carrier system high mo-Received:Jun.09,2023 Revised:Nov.20,2023 Editor:Yuanwei Liu bility communications multiple access

Establishment of a three-dimensional particle library for graded crushed stone based on a new aggregate morphology characterization method

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 117-130页

作者： Haitao Ge Aimin sha Zhenqiang Han School of Future Transportation Chang'an UniversityXi'an 710064China University of Strasbourg INSA StrasbourgCNRSICubeUMR 7357Strasbourg F-67000France School of Highway Chang'an UniversityXi'an 710064China Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China

The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate *** impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory *** discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular ***,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle *** this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate ***,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle *** model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different *** established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.

关键词： Particle library Discrete element method 3D laser scanning Coarse aggregate Morphology characterization Gradation design

基于模糊准则的小波特征选择在人脸识别中的应用

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信息与控制 2005年第1期34卷 50-53,65页

作者：史泽林李德强黄莎白中国科学院沈阳自动化研究所

提出一种基于模糊准则的小波特征选择方法来实现人脸识别.首先,利用模糊准则得到最优小波包分解;其次,亦利用模糊准则对最优小波包分解中特征(小波系数)的分类能力进行评价并排序;再次,选择鉴别能力强的特征并将它们输入到EFM模型以实... 详细信息

提出一种基于模糊准则的小波特征选择方法来实现人脸识别.首先,利用模糊准则得到最优小波包分解;其次,亦利用模糊准则对最优小波包分解中特征(小波系数)的分类能力进行评价并排序;再次,选择鉴别能力强的特征并将它们输入到EFM模型以实现降维,并使用基于最小二乘误差的线性鉴别函数实现分类.人脸识别实验结果表明基于模糊准则的小波特征选择方法的识别率要高于主元分析(PCA)算法.*

关键词：人脸识别小波特征主元分析识别率最优降维明基 EFM 小波系数最小二乘

An improved interval model updating method via adaptive Kriging models

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 497-514页

作者： sha WEI Yifeng CHEN Hu DING Liqun CHEN shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample ***,the surrogate model in IMU methods mostly adopts the one-time construction *** makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU ***,an improved IMU method via the adaptive Kriging models is *** method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey *** optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is *** the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity *** sampling is then performed in key subspaces based on the maximum mean square error(MMSE)*** interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy *** effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical *** results show that the updated results of the interval model are in good agreement with the experimental results.

关键词： interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number

Early screening for post-stroke depression and its effect on functional outcomes, quality of life, and mortality: A meta-analysis

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World Journal of Psychiatry 2024年第9期14卷 1397-1403页

作者： Jie Dai sha-sha Zhao Su-Xiang Zhang Department of Neurology 6 Cangzhou Central HospitalCangzhou 061001Hebei ProvinceChina

BACKGROUND Post-stroke depression(PSD)is a common and debilitating condition affecting stroke survivors,significantly impacting their recovery and overall quality of *** To assess the effects of early PSD screening on functional outcomes,quality of life,and *** From an initial pool of 1.65 articles,6 studies met the inclusion criteria and were selected for *** outcomes were measured using the functional independence measure(FIM).RESULTS The analysis revealed a significant improvement in FIM scores for a PSD scree-ning group compared to controls[standardized mean difference(SMD)=8.90,95%confidence interval(CI):4.65-1..1.,P1..Quality of life was assessed using the Stroke-Specific Quality of Life Scale,with the screening group showing significantly higher scores(SMD=20.83,95%CI:1..27-26.38,P1..Mortality analysis indicated a reduction in five-year mortality rates for the PSD screening *** Early PSD screening enhances functional recovery,improves quality of life,and reduces mortality rates in stroke ***,integrating PSD screening into routine stroke care improves long-term outcomes for patients.

关键词： Post-stroke depression Early screening Functional outcomes Quality of life Mortality