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基于投影寻踪模型的特高含水油藏剩余油可采潜力评价方法

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油气地质与采收率 2024年第1期31卷 137-144页

作者：刘晨冯其红何逸凡张先敏周文胜中国石油大学(华东)石油工程学院山东青岛266580 海洋石油高效开发国家重点实验室北京100028 中海油研究总院有限责任公司北京100028 中海石油(中国)有限公司天津分公司天津300459

影响特高含水油藏剩余油可采潜力的因素极其复杂,且各因素的影响程度差异明显,常规方法多以剩余油饱和度或剩余油储量丰度等单一指标评价剩余油潜力,难以有效指导特高含水油藏剩余油挖潜。在充分考虑特高含水油藏剩余油可采潜力影响因... 详细信息

影响特高含水油藏剩余油可采潜力的因素极其复杂,且各因素的影响程度差异明显,常规方法多以剩余油饱和度或剩余油储量丰度等单一指标评价剩余油潜力,难以有效指导特高含水油藏剩余油挖潜。在充分考虑特高含水油藏剩余油可采潜力影响因素的基础上,综合表征储层非均质性、剩余油可采储量规模、水淹状况以及油水分流能力的差异,构建了特高含水油藏剩余油可采潜力量化评价指标体系,并考虑不同指标对剩余油可采潜力控制程度的差异,将加速遗传算法与投影寻踪模型相结合来确定各评价指标的客观权重,从而构建了剩余油可采潜力指数,形成特高含水油藏剩余油可采潜力量化评价新方法。以渤海Q油田南区主力产层NmIL砂体为例,开展特高含水油藏剩余油可采潜力量化评价,结果表明,新方法可综合表征不同区域位置的储层物性、可采储量丰度和油水分流能力对剩余油可采潜力的影响,实现了主力产层NmIL砂体剩余油可采潜力分布的差异化定量评价,优势可采潜力区域刻画明显,将其作为NmIL砂体下一步井网加密调整潜力区域,以精准指导加密水平井的部署,为特高含水油藏剩余油挖潜提供了一种全新的分析方法与思路。

关键词：特高含水期剩余油可采潜力指数投影寻踪优势潜力丰度

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不同钙离子浓度可通过内质网应激影响人腹膜间皮细胞上皮间质转化

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中华危重病急救医学 2024年第1期36卷 50-55页

作者：郭宝珠程锦绣靳鑫贺玉桃孙羡敏河北北方学院附属第一医院肾内科河北张家口075000

目的探讨不同钙离子浓度通过内质网应激(ERS)对人腹膜间皮细胞(HPMC)上皮间质转化(EMT)的影响。方法体外培养HPMC细胞株HMrSV5并分组处理,对照组、高钙1组、高钙2组分别用含1.25、1.75、2.25 mmol/L钙离子浓度的培养基处理,溶剂对照组用... 详细信息

目的探讨不同钙离子浓度通过内质网应激(ERS)对人腹膜间皮细胞(HPMC)上皮间质转化(EMT)的影响。方法体外培养HPMC细胞株HMrSV5并分组处理,对照组、高钙1组、高钙2组分别用含1.25、1.75、2.25 mmol/L钙离子浓度的培养基处理,溶剂对照组用含1.25 mmol/L生理钙离子浓度及0.1%二甲基亚砜(DMSO)的培养基处理,高钙+溶剂组用含2.25 mmol/L钙离子浓度及0.1%DMSO的培养基处理,高钙+4-苯基丁酸(4-PBA)组用含2.25 mmol/L钙离子浓度及1 mmol/L ERS抑制剂4-PBA的培养基处理。各组处理48 h后,光镜下观察细胞形态学变化;采用免疫荧光染色观察细胞中上皮细胞表型标志蛋白紧密连接蛋白-1(ZO-1)和间质细胞表型标志蛋白α-平滑肌肌动蛋白(α-SMA)的表达;采用荧光定量聚合酶链反应(PCR)检测细胞中EMT标志基因E-钙黏蛋白(E-cadherin)、ZO-1、α-SMA和波形蛋白(Vimentin)的表达;采用蛋白质免疫印迹试验(Western blotting)检测细胞中ERS标志蛋白磷酸化蛋白激酶R样内质网激酶(p-PERK)、磷酸化真核翻译起始因子2α(p-eIF2α)、转录激活因子4(ATF4)和C/EBP同源蛋白(CHOP)的表达。结果与对照组比较,高钙1组和高钙2组HMrSV5细胞变细长、呈纤维化样改变,ZO-1的荧光强度增加、α-SMA的荧光强度减弱,提示细胞从上皮细胞向间质细胞转化;细胞中E-cadherin、ZO-1的mRNA表达明显降低,α-SMA、Vimentin的mRNA表达及p-PERK、p-eIF2α、ATF4、CHOP的蛋白表达明显升高,且高钙2组上述标志基因或蛋白表达较高钙1组变化更明显〔E-cadherin mRNA(2^(-ΔΔCt)):0.53±0.05比0.75±0.09,ZO-1 mRNA(2^(-ΔΔCt)):0.42±0.06比0.69±0.06,α-SMA mRNA(2^(-ΔΔCt)):1.81±0.16比1.32±0.14,Vimentin mRNA(2^(-ΔΔCt)):2.05±0.22比1.48±0.16,p-PERK蛋白(p-PERK/β-actin):0.81±0.09比0.59±0.06,p-eIF2α蛋白(p-eIF2α/β-actin):0.87±0.10比0.50±0.06,ATF4蛋白(ATF4/β-actin):0.93±0.10比0.72±0.06,CHOP蛋白(CHOP/β-actin):0.79±0.09比0.46±0.04,均P<0.05〕。与溶剂对照组比较,2.25 mmol/L高钙处理后,细胞形态学变化、EMT标志基因及ERS标志蛋白的表达变化与高钙2组较对照组的变化趋势一致;与高钙+溶剂组比较,高钙+4-PBA组细胞恢复多边形、鹅卵石样的上皮细胞特征,ZO-1的荧光强度增加、α-SMA的荧光强度减弱,细胞中E-cadherin、ZO-1的mRNA表达明显增加〔E-cadherin mRNA(2^(-ΔΔCt)):0.86±0.09比0.57±0.04,ZO-1 mRNA(2^(-ΔΔCt)):0.81±0.06比0.48±0.05,均P<0.05〕,α-SMA、Vimentin的mRNA表达及p-PERK、p-eIF2α、ATF4、CHOP的蛋白表达明显降低〔α-SMA mRNA(2^(-ΔΔCt)):1.21±0.13比1.77±0.15,Vimentin mRNA(2^(-ΔΔCt)):1.30±0.14比1.94±0.20,p-PERK蛋白(p-PERK/β-actin):0.38±0.04比0.92±0.11,p-eIF2α蛋白(p-eIF2α/β-actin):0.34±0.05比1.05±0.13,ATF4蛋白(ATF4/β-actin):0.57±0.06比0.97±0.11,CHOP蛋白(CHOP/β-actin):0.51±0.04比0.90±0.12,均P<0.05〕。结论1.75 mmol/L和2.25 mmol/L的高钙离子浓度可通过激活ERS的方式促进HPMC发生EMT。

关键词：腹膜透析腹膜纤维化人腹膜间皮细胞上皮间质转化钙离子浓度内质网应激

Lunar titanium abundance characterization using Chang'E-1 IIM data

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 170-178页

作者： WANG xianmin NIU RuiQing Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China

Lunar titanium characterization is an important goal of the China Lunar Exploration Program. We suggest a method to determine the lunar titanium abundance using Chang'E-1 IIM (Interference Imaging Spectrometer) imagery. Using samples from Apollo and Luna landing sites, the method firstly establishes the spectral parameters that possess good non-linear correlations with lunar titanium abundance. Secondly, the method estimates lunar titanium abundance using a DT-SVM (Decision Tree Method C5.0-Support Vector Machine) method. Namely, according to the established spectral parameters, it uses the C5.0 algorithm to classify the titanium abundance into the 4 classes of very low, low, intermediate and high. Then, in terms of the spectral parameters and the corresponding classes, it employs the SVM to estimate the titanium abundance. The method makes good use of hyperspectral information, analyzes the nonlinear correlations between spectral characteristics of lunar soils and the composition parameter, and well determines the titanium abundance. Validated by the Apollo and Luna station samples, the RMSE (root mean square error) is 0.72wt% TiO2 and the correlation coefficient of the measured and predicted values is 97.29%. So, the method proposed in this paper has a good predictive capability for TiO2 abundance on the lunar surface. The maps of TiO2 content in the partial region of Sinus Iridium, the Apollo 17 landing site and the Apollo 16 landing site are constructed by our method. This paper demonstrates the potential of IIM data for the investigation of lunar surface chemistry and mineralogy.

关键词： Moon titanium IIM Chang'E-1

A POSTERIORI ERROR ESTIMATES OF A NON-CONFORMING FINITE ELEMENT METHOD FOR PROBLEMS WITH ARTIFICIAL BOUNDARY CONDITIONS

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Journal of Computational Mathematics 2009年第6期27卷 677-696页

作者： xianmin Xu Zhiping Li LMAM & School of Mathematical Sciences Peking University Beijing 100871 China

An a posteriori error estimator is obtained for a nonconforming finite element approximation of a linear elliptic problem, which is derived from a corresponding unbounded domain problem by applying a nonlocal approximate artificial boundary condition. Our method can be easily extended to obtain a class of a posteriori error estimators for various conforming and nonconforming finite element approximations of problems with different artificial boundary conditions. The reliability and efficiency of our a posteriori error estimator are rigorously proved and are verified by numerical examples.

关键词： a posteriori estimate nonconforming finite element method artificial boundary conditions

谷子抽穗期基因SiGI的表达与单倍型变异分析

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植物遗传资源学报 2024年第9期25卷 1552-1564页

作者：姚琦智慧孟强袁迪张彬刁现民贾冠清山西农业大学农学院中国农业科学院作物科学研究所

谷子抽穗期是决定品种适应性的关键性状，解析抽穗期关键基因的表达规律及其单倍型变异特点可为提升品种改良效率奠定基础。本研究通过全基因组关联分析，发现了一个与抽穗期紧密相关的关联信号，该信号定位于谷子5号染色体的11062649 b... 详细信息

谷子抽穗期是决定品种适应性的关键性状，解析抽穗期关键基因的表达规律及其单倍型变异特点可为提升品种改良效率奠定基础。本研究通过全基因组关联分析，发现了一个与抽穗期紧密相关的关联信号，该信号定位于谷子5号染色体的11062649 bp处，该位点附近存在一个拟南芥抽穗期基因AtGI的同源基因SiGI。使用qRT-PCR技术研究短日照（10 h光照/14 h黑暗）条件下SiGI 24 h节律变化规律，并对其进行了组织时空表达及亚细胞定位分析。利用697份谷子品种，分析SiGI编码区和启动子区的遗传多态性和单倍型变异规律，并对单倍型的表型效应进行鉴定。结果显示，SiGI在光周期响应组织（根、茎、叶等）中高表达，亚细胞定位于细胞核，在傍晚表达量上调，呈现出24 h节律性表达模式。SiGI在不同谷子品种中存在丰富的多态性，其中，启动子Hap-6单倍型较Hap-3单倍型品种的相对表达量显著上调了约1.5倍（P=0.0083）。在8个不同种植环境下，Hap-6单倍型品种的抽穗期显著提前，并在4个环境中株高显著降低。结果表明SiGI基因的Hap-6单倍型具有早熟且对产量影响较小的优势，可作为优异单倍型用于分子育种选择。

关键词：全基因组关联分析单倍型分析节律性表达抽穗期谷子

A level set method for reliability-based topology optimization of compliant mechanisms

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Science China(Technological Sciences) 2008年第4期51卷 443-455页

作者： ZHANG xianmin OUYANG GaoFei School of Mechanical Engineering South China University of TechnologyGuangzhou 510640China

Based on the level set model and the reliability theory, a numerical approach of reliability-based topology optimization for compliant mechanisms with multiple inputs and outputs is presented. A multi-objective topology optimal model of compliant mechanisms considering uncertainties of the loads, material properties, and member geometries is developed. The reliability analysis and topology optimization are integrated in the optimal iterative process. The reliabilities of the compliant mechanisms are evaluated by using the first order reliability method. Meanwhile, the problem of structural topology optimization is solved by the level set method which is flexible in handling complex topological changes and concise in describing the boundary shape of the mechanism. Numerical examples show the importance of considering the stochastic nature of the compliant mechanisms in the topology optimization process.

关键词： compliant mechanism reliability analysis topology optimization level set method

湿润烧伤膏对糖尿病足创面组织中MMP-2、MMP-9、Bcl-2、Bax水平的影响

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中国烧伤创疡杂志 2024年第2期36卷 85-89页

作者：韩芳侯献敏郑州大学附属郑州中心医院创面修复中心河南郑州450007

目的探讨湿润烧伤膏(MEBO)对糖尿病足创面组织中基质金属蛋白酶(MMP)-2、MMP-9、B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)水平的影响。方法选取2020年5月至2022年5月郑州大学附属郑州中心医院收治的55例糖尿病足患者作为研究对象,按... 详细信息

目的探讨湿润烧伤膏(MEBO)对糖尿病足创面组织中基质金属蛋白酶(MMP)-2、MMP-9、B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)水平的影响。方法选取2020年5月至2022年5月郑州大学附属郑州中心医院收治的55例糖尿病足患者作为研究对象,按照不同治疗方法将其分为MEBO组(35例)和VSD组(20例),MEBO组患者局部创面采用MEBO治疗,VSD组患者局部创面采用负压封闭引流(VSD)治疗,对比观察两组患者创面面积,创面组织中MMP-2、MMP-9、Bcl-2、Bax水平及临床疗效。结果治疗第7、21天,MEBO组患者创面面积均明显小于VSD组(t=2.719、5.268,P=0.009、P<0.001),创面组织中MMP-2、MMP-9、Bax水平均明显低于VSD组(MMP-2:t=2.138、2.202,P=0.037、0.032;MMP-9:t=2.129、2.476,P=0.038、0.017;Bax:t=3.623、3.038,P=0.001、0.004),Bcl-2水平均明显高于VSD组(t=2.040、3.054,P=0.046、0.004);治疗21 d后,MEBO组患者中显效23例、有效10例、无效2例,明显优于VSD组患者的显效8例、有效7例、无效5例(Z=-2.126,P=0.033)。结论MEBO可通过降低糖尿病足创面组织中MMP-2、MMP-9、Bax水平以及提高Bcl-2水平促进创面愈合。

关键词：湿润烧伤膏负压封闭引流糖尿病足基质金属蛋白酶-2 B细胞淋巴瘤-2 基质金属蛋白酶-9 Bcl-2相关X蛋白

Design and Myoelectric Control of an Anthropomorphic Prosthetic Hand

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Journal of Bionic Engineering 2017年第1期14卷 47-59页

作者： Nianfeng Wang Kunyi Lao xianmin Zhang Guangdong Province Key Laboratory of Precision Equipment and Manufacturing Technology South China University of Technology Guangzhou 510640 China

This paper presents an anthropomorphic prosthetic hand using flexure hinges, which is controlled by the surface electromyography （sEMG） signals from 2 electrodes only. The prosthetic hand has compact structure with 5 fingers and 4 Degree of Freedoms （DoFs） driven by 4 independent actuators. Helical springs are used as elastic joints and the joints of each finger are coupled by tendons. The myoelectric control system which can classify 8 prehensile hand gestures is built. Pattern recognition is employed where Mean Absolute Value （MAV）, Variance （VAR）, the fourth-order Autoregressive （AR） coefficient and Sample Entropy （SE） are chosen as the optimal feature set and Linear Discriminant Analysis （LDA） is utilized to reduce the dimension. A decision of hand gestures is generated by LDA classifier after the current projected feature set and the previous one are ＂pre-smoothed＂, and then the final decision is obtained when the current decision and previous decisions are ＂post-smoothed＂ from the decisions flow. The prosthetic hand can perform prehensile postures for activities of daily living and carry objects under the control of EMG signals.

关键词： electromyography anthropomorphic prosthetic hand myoelectric control pattern recognition prehensile gestures

Pseudo-rigid-body Model for Corrugated Cantilever Beam Used in Compliant Mechanisms

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 122-129页

作者： WANG Nianfeng LIANG Xiaohe ZHANG xianmin Guangdong Province Key Laboratory of Precision Equipment and Manufacturing Technology South China University of Technology State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Common compliant joints generally have limited range of motion, reduced fatigue life and high stress concentration. To overcome these shortcomings, periodically corrugated cantilever beam is applied to design compliant joints. Basic corrugated beam unit is modeled by using pseudo-rigid-body method. The trajectory and deformation behavior of periodically corrugated cantilever beam are estimated by the transformation of coordinate and superposition of the deformation of corrugated beam units. Finite element analysis（FEA） is carried out on corrugated cantilever beam to estimate the accuracy of the pseudo-rigid-body model. Results show that the kinetostatic behaviors obtained by this method, which has a relative error less than 6%, has good applicability and corrugated cantilever beam has the characteristics of a large range of motion and high mechanical strength. The corrugated cantilever beam is then applied to design a flexible rotational joint to obtain a larger angle output. The paper proposes a pseudo-rigid-body model for corrugated cantilever beam and designed a flexible rotational joint with large angle output.

关键词： corrugated beam pseudo rigid body method compliant mechanisms