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行硬膜外镇痛的初产妇孕期体重增加对产程和分娩方式的影响

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复旦学报（医学版） 2024年第5期51卷 684-690页

作者：马力胡蓉郭云冬黄绍强孙申复旦大学附属妇产科医院麻醉科上海200090 复旦大学附属妇产科医院产科上海200090 宁夏回族自治区人民医院麻醉科银川750002

目的评估行硬膜外镇痛(epidural analgesia,EA)的初产妇孕期体重增加(gestational weight gain,GWG)对产程和分娩方式的影响。方法本研究回顾性收集了2020年8月至2021年1月复旦大学附属妇产科医院所有单胎足月分娩并且行EA的初产妇的医... 详细信息

目的评估行硬膜外镇痛(epidural analgesia,EA)的初产妇孕期体重增加(gestational weight gain,GWG)对产程和分娩方式的影响。方法本研究回顾性收集了2020年8月至2021年1月复旦大学附属妇产科医院所有单胎足月分娩并且行EA的初产妇的医疗记录,采用t检验和χ2检验评估GWG超标对产程和分娩方式的影响。采用多元回归和多分类Logistic回归分析各因素对产程和分娩方式的影响。结果共计1283名产妇纳入研究,其中GWG超标(研究组)646名,GWG未达标/达标(对照组)637名。在倾向得分匹配(propensity score matching,PSM)之前,与对照组相比,研究组产妇孕前BMI值更高,孕龄更长,伴随症状人数更多(P<0.001)。PSM分析显示,GWG不会对产程及分娩方式产生影响。多元回归分析显示,催产素对第一产程(P=0.001)、第二产程(P<0.001)和分娩方式(P=0.002)均有显著影响,孕龄(P=0.003)对第一产程有显著影响,破膜方式(P=0.003)和合并糖尿病(P=0.015)对第二产程有显著影响,年龄(P<0.001)和孕龄(P=0.019)对分娩方式有显著影响。结论在使用EA的初产妇中,GWG超标产妇的产程和分娩方式与GWG未达标/达标产妇相比差异无统计学意义。

关键词：孕期体重增加(GWG) 产程硬膜外镇痛(EA) 初产妇

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我国民族地区政策性农业担保支农效率评价

河北农业科学 2024年第2期28卷 23-28,76页

作者：郭云冬陈文烈青海民族大学民族学与社会学学院青海西宁810007 青海民族大学经济与管理学院青海西宁810007

自我国政策性农业担保体系组建以来,有效实现了财政资金支农政策的延伸。当前乡村振兴背景下,实现政策性农业担保高质量发展,对提高农业担保支农效率具有重要作用。基于三阶段DEA模型,以2020年政策性农业担保数据为基础,对民族地区政策... 详细信息

自我国政策性农业担保体系组建以来,有效实现了财政资金支农政策的延伸。当前乡村振兴背景下,实现政策性农业担保高质量发展,对提高农业担保支农效率具有重要作用。基于三阶段DEA模型,以2020年政策性农业担保数据为基础,对民族地区政策性农业担保支农效率进行评价。结果表明:(1)民族地区政策性农业担保支农效率整体水平偏低,各省政策性农业担保支农效率差异显著。(2)环境因素和随机扰动因素对民族地区政策性农业担保支农效率影响明显。经济发展水平对政策性农业担保支农效率有明显的增强作用,农业受灾情况对政策性农业担保支农效率具有明显的削弱作用,农业科技水平则有利于政策性农业担保技术转化效率提升。提出持续扩大政策性农业担保投入规模、不断提升政策性农业担保资金使用效率的对策建议。

关键词： DEA 民族地区政策性农业担保支农效率

Elastic Constants of Superconducting MgB2 from Molecular Dynamics Simulations with Shell Model

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Communications in Theoretical Physics 2005年第5X期44卷 936-940页

作者： guo yun-dong CHEN Xiang-Rong YANG Xiang-dong GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China Department of Physics Neijiang Teacher's College Neijiang 641112 China International Centre for Materials Physics the Chinese Academy of Sciences Shenyang 110016 China

The elastic constants of superconducting MgB2 are calculated using a molecular dynamics method (MD)with shell model. The lattice parameters, five independent elastic constants, equations of state (EOS), Debye temperature, and bulk modulus of MgB2 are obtained. Meanwhile, the dependence of the bulk modulus B, the lattice parameters a and c, and the unit cell volume V on the applied pressure are presented. It is demonstrated that the method introduced here can well reproduce the experimental results with a reasonable accuracy.

关键词： MgB2 elastic constants shell model molecular dynamics

High Temperature Spectrum for v3 Band of Carbon Dioxide

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Communications in Theoretical Physics 2007年第5期47卷 892-896页

作者： SONG Xiao-Shu YANG Xiang-dong guo yun-dong WANG Jun CHENG Xin-Lu LING-HURong-Feng Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China School of Physics and Chemistry Guizhou Normal University Guiyang 550001 China

The total internal partition sums （TIPS） are calculated at the temperature up to 6000 K for 12 C16 02. Using the calculated partition functions, we produce the line intensities of v3 band of 12C1602 at several high temperatures. The results show that the calculated line intensities are in very good agreement with those of HITRAN database at the temperature up to 3000 K, which provides a strong support for the calculations of TIPS and line intensities at high temperature. Then the calculation is extended to further high temperature, and the simulated spectra of u3 band of 12C1602 at 5000 and 6000 K are reported.

关键词： partition functions carbon dioxide line intensities high temperature

Study on High-Temperature Spectra of Asymptotic Asymmetric-Top Molecule O_3

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Communications in Theoretical Physics 2008年第8期50卷 481-485页

作者： SONG Xiao-Shu guo yun-dong LING-HU Rong-Feng Lv Bing CHENG Xin-Lu YANG Xiang-dong School of Physics and Chemistry Guizhou Normal University Guiyang 550001 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China Department of Physics Neijiang Teacher＇s College Neijiang 641112 China

The line intensities of 001-000 transition of the asymptotic asymmetric-top Oa molecule at several temperatures are calculated by directly calculating the partition functions and regarding the rotationless transition dipole moment squared as a constant. The calculated values of the total internM partition sums （TIPS） are consistent with the data of HITRAN database with -0.61% at 296 K. The calculated line intensity data at 500 K and 3000 K are also in excellent agreement with the data in HITRAN database with less than 0.659% and 5.458% at 500 K and 3000 K, which provide a strong support for the calculations of partition function and fine intensity at high temperature. Then we extend the calculation to higher temperatures. The line intensities and simulated spectra of v3 band of the asymptotic asymmetric-top O3 molecule at 4000 and 5000 K are reported. The results are of significance for the studying of the molecular high-temperature spectrum including experimental measurements and theoretical calculations.

关键词： asymptotic asymmetric-top molecule line intensities partition functions high temperature spectrum

Phonon density of states and phonon dispersion of superconducting MgB2

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原子与分子物理学报 2006年第B4期23卷 241-245页

作者： guo yun-dong CAI Da-feng ZHOU Li-ping CHEN Xiang - rong YANG Xiang-dong Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 P. R. China Department of Physics Neijiang Teacher＇s College Neijiang 641112 P. R. ehina International Centre for Materials Physics Chinese Academy of Seiences Shenyang 110016 P. R. China

For the superconductor MgB2, we have calculated the phonon density of states (DOS), phonon dispersion and Eliashberg function throughout the Brillouin zone (BZ), using an empirical potential model. The calculated values are consistent with the theoretical and experimental values. The calculated results show our empirical potential model is available for MgB2.

关键词： MgB2 声子密度态经验位势模型超导体声子散射

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo Wenqing YANG Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen dong Yichao Zhu Xu guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped *** article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities *** better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between *** on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five *** the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami *** the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation

Recent Advances in Pd-Catalyzed Reactions Involving the “On-Water” Mechanism

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Chinese Journal of Chemistry 2024年第5期42卷 533-542页

作者： dong Wei guo-Qiang Lin State Key Laboratory of Systems Medicine for Cancer Shanghai Cancer InstituteShanghai Key Laboratory of Systems Regulation and Clinical Translation for CancerRen Ji HospitalShanghai Jiao Tong University School of MedicineShanghai200127 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China

As the chemical industry grapples with the need for more eco-friendly practices,the use of water as a reaction medium is gaining attraction in organic *** mini-review delves into Pd-catalyzed reactions that utilize the "on-water" mechanism,spanning from 2019 to late *** reactions are neatly categorized into several types: (A) Catalytic C—H activations,(B) Mizoroki- Heck-type reactions,(C) Suzuki-Miyaura reactions,and (D) Cyclization *** showcasing the potential of water as a sustainable reaction medium for organic transformations,these reactions leave no doubt about the importance of embracing eco-friendly practices in the chemical *** Scientists In 1980,a seminal work by Breslow et *** an acceleration of reaction rate in the Diels-Alder *** and co-workers noted a significant increase in the rate of the [2σ+2σ+2π] cycloaddition of quadricyclane and dimethyl azodicarboxylate (DMAD) when the reaction was conducted in water,as opposed to when it was carried out in organic *** term "on-water" was then coined to describe this *** strategy was further expanded to transition-metal catalyzed transformations by Ackermann in ***,Varma and Leazer disclosed a Pd-catalyzed Mizoroki-Heck type arylation of alkenes with diaryliodonium salts “on-water”.The enantioselective version of "on-water" process was not realized until 2014 by the Zhou *** on,the Schaub group described a Pd-catalyzed Suzuki–Miyaura coupling reaction of electron-poor aryl chlorides with water,using only 50 ppm of catalyst *** recently,Liu and Lin extended the "on-water" strategy to Pd-catalyzed double Mizoroki-Heck *** mini-review has focused on Pd-catalyzed reactions involving the “on-water” mechanism.

关键词： Pd-catalyzed “On-water” Green chemistry Aqueous reactions Mechanism Methodology and reactions Mizoroki-Heck reaction Cross-coupling