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Clinical effects of phospholipase D2 in attenuating acute pancreatitis

World Journal of Gastroenterology 2025年第2期31卷 52-60页

作者： Jin-wei niu Guo-Chao Zhang Wu Ning Hai-Bin Liu Hua Yang Chao-Feng Li Department of General Surgery China-Japan Friendship HospitalBeijing 100029China

BACKGROUND The objective of the current study was to elucidate the clinical mechanism through which phospholipase D2(PLD2)exerted a regulatory effect on neutrophil migra-tion,thereby alleviating the progression of acute *** To elucidate the clinical mechanism through which PLD2 exerted a regulatory effect on neutrophil migration,thereby alleviating the progression of acute *** The study involved 90 patients diagnosed with acute pancreatitis,admitted to our hospital between March 2020 and November 2022.A retrospective analysis was conducted,categorizing patients based on Ranson score severity into mild(n=25),moderate(n=30),and severe(n=35)*** data was collected for each *** blot analysis assessed PLD2 protein expression in patient ***-time reverse transcription polymerase chain reaction was used to evaluate the mRNA expression of chemokine receptors associated with neutrophil *** levels of inflammatory factors in patients were detected using enzyme-linked immunosorbent *** migration tests were conducted to compare migration of neutrophils across groups and analyze the influence of PLD2 on neutrophil *** Overall data analysis did not find significant differences between patient groups(P>0.05).The expression of PLD2 protein in the severe group was lower than that in the moderate and mild groups(P<0.05).The expression level of PLD2 in the moderate group was also lower than that in the mild group(P<0.05).The severity of acute pancreatitis is negatively correlated with PLD2 expression(r=-0.75,P=0.002).The mRNA levels of C-X-C chemokine receptor type 1,C-X-C chemokine receptor type 2,C-C chemokine receptor type 2,and C-C chemokine receptor type 5 in the severe group are significantly higher than those in the moderate and mild groups(P<0.05),and the expression levels in the moderate group are also higher than those in the mild group(P<0.05).The levels of C-reactive protein,tumo

关键词： Phospholipase D2 Neutrophil migration Acute pancreatitis Retrospective analysis Inflammatory response

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非对称因素下热轧机工作辊耦合振动机理研究

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塑性工程学报 2025年第1期32卷 242-254页

作者：张明丁子洪杨彦博牛国伟河北工程大学机械与装备工程学院河北邯郸056038 河北省冀南新区现代装备制造协同创新中心河北邯郸056000

针对实际热轧机振动现象,对热轧机轧制振动机理进行研究分析。考虑轧制变形区的动态特性,分别建立上下工作辊的轧制力模型与摩擦因数模型,体现实际轧制过程中上下工作辊不同的动态特性。结合上下工作辊不同的等效水平刚度和等效水平阻尼... 详细信息

针对实际热轧机振动现象,对热轧机轧制振动机理进行研究分析。考虑轧制变形区的动态特性,分别建立上下工作辊的轧制力模型与摩擦因数模型,体现实际轧制过程中上下工作辊不同的动态特性。结合上下工作辊不同的等效水平刚度和等效水平阻尼,建立热轧机结构模型,并对该模型进行模拟仿真分析。仿真结果表明,热轧机振动形式表现为上下工作辊在水平和扭转振动时均为反向振动,模拟振动频率与实际振动频率在一定误差范围内,模拟振动幅值与实际振动幅值相符。最后分析了热轧机结构和轧制工艺参数对热轧机振动的影响,并对其进行热轧机振动抑振分析,结果表明增大工作辊的最大静摩擦因数、适当增大下工作辊的半径可以有效控制热轧机振动的幅度。

关键词：轧制力模型摩擦因数模型非对称因素热轧机结构模型振动抑制

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Numerical study of a supercritical airfoil/wing with variable-camber technology

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Chinese Journal of Aeronautics 2020年第7期33卷 1850-1866页

作者： wei niu Yufei ZHANG Haixin CHEN Miao ZHANG School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Shanghai Aircraft Design and Research Institute Shanghai 201210China

Variable-camber technology is considered an effective way to adaptively improve the aerodynamic performance of aircraft under various flight *** paper studies the aerodynamic characteristics of the trailing-edge variable-camber technology by means of Computational Fluid Dynamics(CFD)and a drag decomposition ***-edge variable-camber technology can be simply realized by the continuous deflection of the flaps and ailerons of a wing.A supercritical airfoil is used to study the two-dimensional effect of variable-camber technology,and a wide-body airplane model is used to validate the three-dimensional improvement in the wing’s airfoil made by variable-camber *** optimization strategy for airfoil that incorporates variable-camber technology is *** optimization results demonstrate that the proposed method can obtain better results than the traditional segregated shape optimization.

关键词： Aerodynamic optimization CST method Drag decomposition Supercritical airfoil/wing Variable-camber technology

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机器学习预测肱骨近端骨折钢板内固定后继发性螺钉切出的风险

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中国组织工程研究 2025年第15期29卷 3179-3187页

作者：徐大星涂泽松纪木强许伟鹏牛维广州中医药大学广东省广州市510006 佛山市中医院三水医院骨科广东省佛山市528100 佛山市中医院骨科广东省佛山市528000 广东省中医院关节外科广东省广州市510120

背景:继发性螺钉切出关节面是肱骨近端骨折锁定钢板内固定术后的主要并发症之一,切出的螺钉会磨损关节盂和引起肩峰撞击,影响肩关节功能。因此,准确的风险预测有积极的临床意义。目的:通过机器学习方法筛选肱骨近端骨折钢板内固定后继... 详细信息

背景:继发性螺钉切出关节面是肱骨近端骨折锁定钢板内固定术后的主要并发症之一,切出的螺钉会磨损关节盂和引起肩峰撞击,影响肩关节功能。因此,准确的风险预测有积极的临床意义。目的:通过机器学习方法筛选肱骨近端骨折钢板内固定后继发性螺钉切出的风险因素,开发并验证风险预测模型,便于临床医生早期甄别并干预高风险患者。方法:收集2013年6月至2022年6月接受锁定钢板内固定治疗的214例肱骨近端骨折患者的临床资料作为训练组建立模型,将同一时间段另一医院收治的同类患者61例纳入外部验证组。按照患者术后是否出现继发性螺钉切出,分为螺钉切出组和螺钉维持组。训练组利用随机森林、支持向量机、逻辑回归3种机器学习算法构建预测模型;采用递归特征消除法、10折交叉验证重抽样作为变量的筛选方法,并将3种模型准确度最高时纳入变量的交集作为与螺钉切出高度相关的可靠风险变量。通过R语言软件构建动态预测模型,以网页计算器形式展示,并对模型进行内、外部验证。模型内部检验采用Bootstrap法重抽样1000次,使用受试者工作特征曲线下面积、校准曲线、临床决策曲线评价模型的区分度、校准能力及临床应用价值。通过Youden指数确定预测模型的最佳风险分界值,据此将外部验证组患者分为高、低风险组,根据模型风险预测能力的准确度来评价其稳定性和外延性。结果与结论:①机器学习算法筛选出继发性螺钉切出高度相关的4个风险变量,分别为肱骨近端内侧柱皮质支撑、三角肌结节指数、骨折类型及术后复位情况;②构建的风险预测模型表现出良好的区分度和准确度[曲线下面积=0.874,95%置信区间(0.827,0.922)],校准曲线显示模型预测风险和实际发生风险有较好的一致性;③临床决策曲线提示风险阈值概率在0.1-0.75范围内时,模型具有较好的临床适用性;④风险概率为26%是模型风险分层的最佳阈值,外部验证组利用模型风险分层预测螺钉切出的总正确率为84%;⑤结果说明该风险预测模型准确度和外延性较好,可为指导临床治疗提供依据。

关键词：肱骨近端骨折继发性螺钉切出机器学习影响因素风险预测模型

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A perspective on general direction and challenges facing antimicrobial peptides

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Chinese Chemical Letters 2017年第4期28卷 703-708页

作者： Meng Zhu Peng Liu Zhong-wei niu Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The emergence of drug resistant bacterium threatens the global public healthcare *** urgent need to obtain new antimicrobials has driven antimicrobial peptides（AMPs） research into *** we give a brief introduction of the recent progress of AMPs regarding their structures,properties,production and modification,and antimicrobial ***,this review will give an insight into the trends and challenges facing on this particular kind of antimicrobial materials.

关键词： Antimicrobial peptides(AMPs) Drug resistance Biomaterials Antimicrobial materials Antimicrobial mechanism

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Calculating standard captured γ spectra of formation elements

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Petroleum Science 2012年第4期9卷 463-468页

作者： Wu Wensheng Xiao Lizhi Zhang Lijuan niu wei State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China

Multi-element gamma-ray spectrum logging requires standard spectra of individual elements for its *** the standard element spectra are usually derived using Monte Carlo simulation of either a pure element or its oxide,we synthesized the standard neutron captured γ spectra（as would be observed using a NaI（Tl） detector） of elements H,Si,Ca and Fe from each element and its *** compare the standard spectra from the elements and oxides,we operated three simulations of sandstone,limestone and mixed formation of sandstone and limestone each with ten different porosities,and used the two kinds of standard spectra to analyze the mixed spectra modeled from sandstone and limestone *** results show that the standard element spectra from oxides have more prominent energy peaks than the standard spectra from pure *** calculated formation element contents are close to the theoretical values when the standard element spectra from oxides are used to analyze the formation mixed ***,the formation element standard spectra should be calculated from oxide models in the analysis of neutron captured γ spectra by logging tools.

关键词： Standard spectrum spectrum analysis neutron captured γ spectrum formation element

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SYMBOLIC COMPUTATION FOR THE QUALITATIVE THEORY OF DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2022年第6期42卷 2478-2504页

作者： Bo HUANG wei niu Dongming WANG LMIB-School of Mathematical Sciences Beihang UniversityBeijing 100191China Ecole Centrale de Pekin Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310051China Centre National de la Recherche Scientifique 75794 Paris Cedea 16France

This paper provides a survey on symbolic computational approaches for the analysis of qualitative behaviors of systems of ordinary differential equations,focusing on symbolic and algebraic analysis for the local stability and bifurcation of limit cycles in the neighborhoods of equilibria and periodic orbits of the systems,with a highlight on applications to computational biology.

关键词： biological systems center-focus limit cycles qualitative analysis symbolic computation

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Numerical simulation of the factors influencing dust in drilling tunnels:Its application

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Mining Science and Technology 2011年第1期21卷 11-15页

作者： niu wei Jiang Zhongan Tian Dongmei Key Laboratory of Ministry of Education for High Efficiency Exploitation and Safety of Metal Mine. Beijing University of Sdence and Technology Beijing 100083 China

Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a *** software package FLUENT was used to numerically simulate dust motion and the results were compared to observed *** simulation agrees with the data taken from an actual working face,which confirms the choice of mathematical model and numerical simulation method. Using the model we predict a set of conditions optimum for reducing dust concentrations at the mine working face.

关键词： Drivage working faceDust concentrationThe gas-solid two-phase flowVentilation method

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Microstructure and kinetics of hot deformation WE43 magnesium alloy

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Rare Metals 2008年第4期27卷 405-409页

作者： GAO Jiacheng WANG Qiang WANG Yong LI wei niu Wenjuan College of Materials Science and Engineering National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China

The effect of compression on the microstructures and flow behavior of WE43 magnesium alloy was investigated in this article. The relationship between flow stress and strain rate was discussed. According to the empirical formula ε = Aδ^n exp （-Q/R T）, the value of heat activation of WE43 magnesium alloys is 297,15 kJ/mol. A mechanism of deformation softening of WE43 alloy in testing hot deformation was identified to be dynamic recrystallization.

关键词： WE43 magnesium alloy hot deformation microstructure kinetics

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Threat Assessment Method Based on Intuitionistic Fuzzy Similarity Measurement Reasoning with Orientation

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China Communications 2014年第6期11卷 119-128页

作者： WANG Yi LIU Sanyang niu wei LIU Kai LIAO Yong State Key Laboratory of Astronautic Dynamics School of Mathematics and Statistics Xi’dian University Air Defense and Antimissile Institute Air Force Engineering University 95824 Unit

The aim of this paper is to propose a threat assessment method based on intuitionistic fuzzy measurement reasoning with orientaion to deal with the shortcomings of the method proposed in [Ying-Jie Lei et al., Journal of Electronics and Information Technology 29(9)(2007)2077-2081] and [Dong-Feng Chen et al., Procedia Engineering 29(5)(2012)3302-3306] the ignorance of the influence of the intuitionistic index's orientation on the membership functions in the reasoning, which caused partial information loss in reasoning process. Therefore, we present a 3D expression of intuitionistic fuzzy similarity measurement, make an analysis of the constraints for intuitionistic fuzzy similarity measurement, and redefine the intuitionistic fuzzy similarity measurement. Moreover, in view of the threat assessment problem, we give the system variables of attribute function and assessment index, set up the reasoning system based on intuitionistic fuzzy similarity measurement with orientation, and design the reasoning rules, reasoning algorithms and fuzzy-resolving algorithms. Finally, through the threat assessment, some typical examples are cited to verify the validity and superiority of the method.

关键词： Intuitionistic fuzzy reasoning Threat assessment Orientation Similaritymeasurement

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