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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG heli liu Lemeng ZHANG Yiran HU Denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical and Manufacturing Engineering University of CyprusNicosia 1678Cyprus Quaker Houghton Deutschland GmbH Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming *** has been found that these tribological conditions vary spatially and historically with process parameters and contact *** time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application ***,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant *** this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the *** modelling techniques for transient behaviours for metal forming applications are also *** accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

经阴道彩色多普勒超声诊断IVF-ET术后宫内外复合妊娠效果及腹腔镜手术后妊娠结局

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中国计划生育学杂志 2024年第5期32卷 1117-1120页

作者：尚琴琴刘何利河北省沧州市中西医结合医院 061001

目的:探究经阴道彩色多普勒超声在体外受精-胚胎移植(IVF-ET)术后宫内外复合妊娠(HP)诊断应用及腹腔镜手术效果。方法:回顾性分析2020年3月-2022年12月本院生殖医学科接收的80例IVF-ET后HP患者临床资料,分析其超声诊断正确率、临床表现... 详细信息

目的:探究经阴道彩色多普勒超声在体外受精-胚胎移植(IVF-ET)术后宫内外复合妊娠(HP)诊断应用及腹腔镜手术效果。方法:回顾性分析2020年3月-2022年12月本院生殖医学科接收的80例IVF-ET后HP患者临床资料,分析其超声诊断正确率、临床表现、超声声像图特征、腹腔镜手术及妊娠结局。结果:经阴道彩色多普勒超声诊断确诊71例,诊断正确率为88.8%,4例(5.0%)延迟诊断,5例(6.3%)误诊;异位妊娠67例(83.8%)位于子宫附件,13例(16.3%)位于宫角/间质;65例(81.2%)有盆腔积液;超声征象32例(40.0%)为附件区或宫角包块,4例(42.5%)为孕囊或胚芽,14例(17.5%)为胎心及心管搏动。患者均行腹腔镜手术治疗,其中9例(11.3%)发生严重并发症,6例(7.5%)中转开腹手术治疗,50例(62.5%)妊娠自然分娩,21例(26.3%)剖宫产,9例(11.3%)流产。结论:经阴道彩色多普勒超声诊断IVF-ET术后HP的主要手段,诊断符合率近90%,对临床有一定指导意义。

关键词：体外受精-胚胎移植宫内外复合妊娠诊断经阴道彩色多普勒超声腹腔镜手术妊娠结局

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表观遗传修饰调控相分离在神经发育和神经疾病发生中的作用

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军事医学 2024年第2期48卷 148-153页

作者：刘贺丽姜慧慧吴海涛南华大学衡阳医学院军事科学院军事医学研究院研究生协作培养基地湖南衡阳421001 军事科学院军事医学研究院军事认知与脑科学研究所北京100850

近年来生物大分子的液-液相分离在一系列生物学过程中的重要作用已被广泛接受,包括基因的转录和翻译调控、应激反应、自噬以及突触结构的建立等。异常的相分离与多种人类疾病相关,包括神经发育失调和神经退行性疾病。研究表明,与表观遗... 详细信息

近年来生物大分子的液-液相分离在一系列生物学过程中的重要作用已被广泛接受,包括基因的转录和翻译调控、应激反应、自噬以及突触结构的建立等。异常的相分离与多种人类疾病相关,包括神经发育失调和神经退行性疾病。研究表明,与表观遗传修饰相关的一些蛋白也表现出液-液相分离的特征,暗示了表观遗传修饰可能通过调控相分离来调控神经发育和神经疾病。该文概括了表观遗传修饰和相分离在神经发育和疾病中的重要作用,并重点关注表观遗传修饰调控相分离在神经发育和疾病中的重要作用。结合表观遗传修饰和相分离将有助于深入理解神经发育和疾病发生的机制,并进一步为相关疾病的治疗提供新的靶点和策略。

关键词：表观遗传修饰液-液相分离生物凝聚体神经发育神经疾病

超声引导微波消融术与开放式手术治疗甲状腺良性大结节的临床疗效比较

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成都医学院学报 2024年第2期19卷 294-297页

作者：郑斌高峰李静艳魏玮刘何利黄梅张震河北省沧州中西医结合医院超声科沧州061001

目的比较超声引导微波消融(MWA)术与开放式手术治疗甲状腺良性大结节的临床效果。方法选取2020年4月至2022年4月在沧州中西医结合医院收治的96例甲状腺良性大结节患者为研究对象,按照随机数字表法将其分为开放组(实施开放式手术)和MWA... 详细信息

目的比较超声引导微波消融(MWA)术与开放式手术治疗甲状腺良性大结节的临床效果。方法选取2020年4月至2022年4月在沧州中西医结合医院收治的96例甲状腺良性大结节患者为研究对象,按照随机数字表法将其分为开放组(实施开放式手术)和MWA组(实施超声引导MWA术),每组48例。比较两组手术相关指标、结节清除率、甲状腺激素水平、术后并发症发生情况。结果与开放组相比,MWA组手术时间、术中失血量、术后住院天数更少(P0.05)。促甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)在组间及时间的主效应比较,差异有统计学意义(P<0.05)。与开放组相比,术后3、6个月MWA组TSH明显降低(P<0.05),FT3、FT4明显升高(P<0.05)。MWA组并发症发生率(4.17%)低于开放组(18.75%)(P<0.05)。结论超声引导MWA术与开放式手术对甲状腺良性大结节的治疗效果均较好,但超声引导MWA术在减少手术时间、术后并发症及住院时间方面具有优势,并能充分保留甲状腺功能。

关键词：微波消融开放式手术甲状腺良性大结节并发症

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Study on contact fatigue of a wind turbine gear pair considering surface roughness

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Friction 2020年第3期8卷 553-567页

作者： heli liu Huaiju liu Caichao ZHU Zhangdong SUN Houyi BAI State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400030China Hubei University of Automotive Technology Shiyan 442002HubeiChina Chongqing Wangjiang Industrial Co.Chongqing 400071China

Contact fatigue issues become more and more crucial in gear industry as they significantly affect the reliability and service life of associated mechanical systems such as wind turbine *** contact fatigue behavior is mostly determined by the mechanical properties of materials and stress fields near the contact area,which is further influenced by the lubrication and surface roughness due to pressure *** this study,a numerical model incorporating the lubrication state,tooth surface roughness,residual stress,and mechanical properties of the material is developed to determine the contact fatigue behavior of a megawatt level wind turbine carburized *** variations of the hardness and residual stress along the depth were characterized by the Vickers hardness measurement and X-ray diffraction test,*** elastohydrodynamic lubrication theory was applied to predict the contact pressure distribution,highlighting the influence of the surface roughness that stemed from the original measurement through an optical *** stress histories of the studied material points during a complete contact loading cycle were fast calculated using the discreteconcrete fast Fourier transformation(DC-FFT)*** Dang Van diagrams under different working conditions were determined to estimate the contact fatigue failure *** effect of the root mean square(RMS)value of the surface roughness on the failure risk at critical material points were discussed in *** revealed that the surface roughness significantly increases the contact fatigue failure risk within a shallow area,and the maximum risk appears near the surface.

关键词： carburized gear contact fatigue surface roughness residual stress Dang Van criterion

Tribological behavior of coated spur gear pairs with tooth surface roughness

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Friction 2019年第2期7卷 117-128页

作者： Huaiju liu heli liu Caichao ZHU Peitang WEI Jinyuan TANG State Key Laboratory of Mechanical Transmissions Chongqing University State Key Laboratory of High Performance Complex Manufacturing Central South University

Coating is an effective way to reduce friction and wear and to improve the contact-fatigue lives of gear components, which further guarantees a longer service life and better reliability of industrial machinery. The fact that the influence coefficient linking the tractions and stress components could not be expressed explicitly increases the difficulty of coated solids contact analysis. The complicated tribological behavior between tooth surfaces influenced by lubrication and surface roughness further adds difficulty to the coated gear pair contact problems. A numerical elastohydrodynamic lubricated(EHL) contact model of a coated gear pair is proposed by considering the coupled effects of gear kinematics, coating properties, lubrication, and surface roughness. The frequency response function and the discrete convolute, fast Fourier transformation(DC-FFT) method are combined to calculate the surface deformation and the subsurface stress fields at each meshing position along the line of action(LOA). The Ree-Eyring fluid is assumed to incorporate the non-Newtonian effect, which is represented in the generalized Reynolds equation. Influences of the ratio between the Young's modulus of the coating and the substrate on the contact performance, such as pressure, film thickness, tooth friction coefficient, and subsurface stress field, are studied. The effect of the root mean square(RMS) value of the tooth surface roughness is studied by introducing the roughness data, deterministically measured by an optical profiler.

关键词： coating gear elastohydrodynamic lubrication (EHL) surface roughness

Erratum to:Study on contact fatigue of a wind turbine gear pair considering surface roughness

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Friction 2022年第7期10卷 1135-1135页

Erratum to Friction(2019)https://***/10.1007/s40544-019-0277-3 The article“Study on contact fatigue of a wind turbine gear pair considering surface roughness”,written by heli liu,Huaiju liu,Caichao ZHU,Zhangdong SUN,Houyi BAI,was erroneously originally published online without open *** online first publication this was corrected and the article is now an open access *** article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License(http://***/licenses/by/4.0/).

关键词： online roughness fatigue

Effects of Three Humic Acid Foliar Fertilizers on Quality and Photosynthetic Characteristics of Hawthorn

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Asian Agricultural Research 2024年第7期16卷 48-52页

作者： Jia WANG Xinyu LUO heli SHANG Dongsheng LAN Qi liu Jingtao ZHU College of Horticultural Science&Technology Hebei Normal University of Science&TechnologyQinhuangdao 066000China Bureau of Agriculture and Rural Affairs of Kuancheng Manchu Autonomous County Chengde 067300China Hebei(Chengde)Hawthorn Industry Technology Research Institute Chengde 067304China

[Objectives]To investigate the effects of three foliar fertilizers on photosynthetic characteristics,fruit quality and yield of hawthorn.[Methods]Taking hawthorn foliar fertilization as the reference,the photosynthetic rate,transpiration rate,intercellular CO 2 concentration,stomatal conductance and single fruit weight of hawthorn leaves were measured under different concentrations of foliar fertilizer.[Results]The results showed that the photosynthetic rate,transpiration rate and stomatal conductance of hawthorn leaves increased significantly,while the intercellular CO 2 concentration ***,the fish protein peptide foliar fertilizer performed best,with net photosynthetic rate and transpiration rate increased by 57.22%and 57.51%,*** the three foliar fertilizers significantly reduced the intercellular CO 2 *** addition,fertilization significantly increased the single fruit weight of hawthorn,and the effect of fermented fulvic acid foliar fertilizer was the most significant,with the highest growth rate of 68.49%.[Conclusions]Spraying foliar fertilizer significantly increased the content of Vc,titratable acid,anthocyanin and soluble solids of hawthorn fruit,among which fermented fulvic acid foliar fertilizer had the optimal effect.

关键词： Hawthorn Humic acid Fulvic acid Fish protein peptide Leaf function Fruit quality

不同浓度丙氨酰谷氨酰胺用于胃肠肿瘤术后患者肠外营养比较的随机对照临床试验

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中国普通外科杂志 2023年第10期32卷 1539-1551页

作者：梁宏岩葛杰刘婷赵庭雨谢凯强刘合利唐密密中南大学湘雅医院药学部湖南长沙410008 国家老年疾病临床医学研究中心(湘雅医院) 湖南长沙410008 中南大学湘雅医院胃肠外科湖南长沙410008

背景与目的:合理的营养支持可为胃肠肿瘤术后患者提供营养物质、并促进患者康复。肠外营养中添加丙氨酰谷氨酰胺(Ala-Gln)有助于改善患者临床结局,但关于Ala-Gln的占比浓度,国内、外药品说明书及临床实际应用有明显不同。因此,本研究探... 详细信息

背景与目的:合理的营养支持可为胃肠肿瘤术后患者提供营养物质、并促进患者康复。肠外营养中添加丙氨酰谷氨酰胺(Ala-Gln)有助于改善患者临床结局,但关于Ala-Gln的占比浓度,国内、外药品说明书及临床实际应用有明显不同。因此,本研究探究肠外营养中不同占比浓度Ala-Gln对胃肠肿瘤患者术后营养、肝肾功能、炎症/免疫状态等的影响,以期为Ala-Gln规范使用提供参考。方法:本研究为随机对照临床试验,纳入2021年6月—2022年4月入住中南大学湘雅医院胃肠外科胃肠肿瘤术后行肠外营养支持患者,并将患者随机分为低占比组(肠外营养中Ala-Gln剂量占总氨基酸20%)与高占比组(肠外营养中Ala-Gln剂量占总氨基酸30%),两组患者均在术后第1天开始通过中心静脉给予肠外营养制剂支持(1次/d,持续输注8~12 h)。在术前、肠外营养结束后1 d进行营养指标、肝肾功能及炎症/免疫指标监测,在医院病历系统收集患者术后感染/并发症、术后住院时间及住院费用等信息。结果:本研究纳入77例患者,低占比组39例,高占比组38例。两组患者的一般资料、术前所有营养、肝肾功能及炎症免疫指标差异均无统计学意义(均P>0.05)。重复测量方差分析结果显示,肠外营养结束后1 d,所有患者的前白蛋白、总蛋白(TP)、血清白蛋白(ALB)、血红蛋白、总胆汁酸水平,以及T淋巴细胞(CD3+、CD4+、CD8+)、免疫球蛋白(IgG、IgA、IgM)水平均较术前明显降低,总胆红素、直接胆红素、丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、尿素的术后水平,以及炎症因子、辅助性T细胞/抑制性T细胞比值(Th/Ts)、补体C4术后水平均较术前明显升高(均P0.05);TP(P=0.032)和ALB(P=0.008)存在分组与时间交互作用。多元线性回归进一步分析结果显示,试验分组对TP和ALB结果无明显影响(均P>0.05)。两组患者术后感染/并发症发生率、术后住院时间及住院费用差异均无统计学意义(均P>0.05)。结论:肠外营养中添加不同占比浓度Ala-Gln(占总氨基酸20%vs.占总氨基酸30%)对胃肠肿瘤术后患者的营养、肝肾功能指标以及术后恢复的影响无显著差异,在免疫调节方面,较高的Ala-Gln占比对T淋巴细胞免疫调节作用更优。临床上应该结合患者情况,选择合适的Ala-Gln占比浓度。

关键词：胃肠肿瘤胃肠外营养谷氨酰胺临床对照试验

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结直肠癌液体活检的临床应用进展

中国普通外科杂志 2019年第9期28卷 1143-1149页

作者：刘鹏刘合利中南大学湘雅医院胃肠外科湖南长沙410008

结直肠癌(CRC)是严重危害公众健康的一类疾病。早诊断早治疗已经成为改善CRC患者预后的关键。近年来,液体活检以其无创性、实时性及可重复性等优势在临床工作中发挥越来越重要的作用。笔者对各种液体活检技术在CRC中的临床应用进行综述。

关键词：结直肠肿瘤液体活检肿瘤细胞,循环循环肿瘤DNA 综述文献