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颈动脉内中膜厚度与亚临床左心室收缩功能的关系

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南京医科大学学报（自然科学版） 2024年第4期44卷 491-498,510页

作者：李一博张雪梁君雅花木莲张思奇高云陈超赵熙璇何姗姗王新月周天娜何安霞刘鸣南京中医药大学附属医院(江苏省中医院)心内科江苏南京210029 南京中医药大学附属医院(江苏省中医院)高血压研究所江苏南京210029 南京中医药大学附属医院(江苏省中医院)功能检查科江苏南京210029 南京中医药大学附属医院(江苏省中医院)超声医学科江苏南京210029

目的:在江苏丹阳社区人群中探讨颈动脉内中膜厚度(carotid intima-media thickness,c IMT)与亚临床左心室功能的关系。方法:研究对象为2021年在江苏省丹阳市车站社区招募的受试者。使用GE Vivid E90超声仪测量分析c IMT;二维斑点追踪技... 详细信息

目的:在江苏丹阳社区人群中探讨颈动脉内中膜厚度(carotid intima-media thickness,c IMT)与亚临床左心室功能的关系。方法:研究对象为2021年在江苏省丹阳市车站社区招募的受试者。使用GE Vivid E90超声仪测量分析c IMT;二维斑点追踪技术采集左心室整体纵向应变(left ventricular global longitudinal strain,LVGLS)作为评估亚临床收缩功能的指标,二尖瓣口血流频谱和组织多普勒成像采集e’和E/e’比值作为评估亚临床舒张功能的指标。结果:研究共计纳入561例,年龄(58.2±11.7)岁,其中女339例(60.4%)。首先使用三分位法将cIMT作为分类变量分析,在单因素分析中,除了左心室射血分数外,LVGLS,E/A和e’均随着cIMT三分位数从低到高下降,而E/e’比值随着cIMT三分位数从低到高增加(均P_(trend)≤0.002)。然而,进一步进行多因素校正分析后,只有LVGLS仍随着c IMT三分位数从低到高下降(P<0.05)。进一步将c IMT自然对数转换后进行连续变量分析,结果与分类变量分析结果类似,仅有LVGLS与cIMT显著负相关(r=-0.087,P=0.041);并且在回归分析中也发现了类似的结果(β=-1.12,P=0.041)。结论:在江苏丹阳社区人群中,cIMT增厚与GLS减低独立相关。

关键词：颈动脉内中膜厚度亚临床左心室收缩功能整体纵向应变左心室舒张功能

Celastrol regulates the oligomeric state and chaperone activity of αB-crystallin linked with protein homeostasis in the lens

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Fundamental Research 2024年第2期4卷 394-400页

作者： Huaxia Wang Qing Tian Ying Zhang yibo Xi lidan Hu Ke Yao Jingyuan li Xiangjun Chen Eye Center of the Second Affiliated Hospital Zhejiang University School of Medicine88 Jiefang RoadHangzhou 310009China Institute of Translational Medicine Zhejiang University School of Medicine268 Kaixuan RoadHangzhou 310020China. State Key Laboratory of Membrane Biology School of Life SciencesTsinghua UniversityBeijing 100084China The Children’s Hospital Zhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityZheda Road 38Hangzhou 310027China

Protein misfolding and aggregation are crucial pathogenic factors for cataracts,which are the leading cause of visual impairment worldwide.α-crystallin,as a small molecular chaperone,is involved in preventing protein misfolding and maintaining lens *** chaperone activity of α-crystallin depends on its oligomeric *** previous work identified a natural compound,celastrol,which could regulate the oligomeric state of α*** this work,based on the UNcle and SEC analysis,we found that celastrol induced𝛼αB-crystallin to form large *** oligomer formation enhanced the chaperone activity of αB-crystallin and prevented aggregation of the cataract-causing mutant α*** interactions between𝛼αB-crystallin and celastrol were detected by the FRET(Fluorescence Resonance Energy Transfer)technique,and verified by molecular *** least 9 binding patterns were recognized,and some binding sites covered the groove structure of α***,αB-R120G,a cataract-causing mutation located at the groove structure,and celastrol can decrease the aggregates of α***,our results suggested celastrol not only promoted the formation of large αB-crystallin oligomers,which enhanced its chaperone activity,but also bound to the groove structure of its α-crystallin domain to maintain its structural *** might serve as a chemical and pharmacological chaperone for cataract treatment.

关键词： αB-crystallin Celastrol Interactions Oligomeric state Chaperone activity Structural stability

基于Halbach阵列电磁超声纵波换能器优化设计

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电工技术学报 2021年第21期36卷 4408-4417页

作者：蔡智超李毅博华东交通大学电气与自动化工程学院南昌330013

传统电磁超声纵波换能器换能效率低,水平偏置磁场弱且无法被充分利用,导致回波信号幅值小,影响检测结果的准确性。该文应用一种新型纵波换能器,其永磁体磁极方向按照Halbach阵列排布,能够显著增强水平磁场。为提高其回波幅值,利用有限... 详细信息

传统电磁超声纵波换能器换能效率低,水平偏置磁场弱且无法被充分利用,导致回波信号幅值小,影响检测结果的准确性。该文应用一种新型纵波换能器,其永磁体磁极方向按照Halbach阵列排布,能够显著增强水平磁场。为提高其回波幅值,利用有限元软件进行建模,分别采用正交试验和均匀试验方法,在考虑线圈匝数的前提下,对换能器参数进行优化。仿真结果表明,降低导线间距、导线宽度和导线高度,将永磁体提离距离固定在合适范围内,均可以增强回波信号;设置合适的激励电流频率,能够使得声衰减和回波幅值处于适中水平,有利于检测。实验结果表明,优化后的换能器相较于优化前回波幅值提高了83%。

关键词：电磁超声换能器纵波 Halbach阵列优化设计正交试验均匀试验

A Polyvinyl Alcohol/Acrylamide Hydrogel with Enhanced Mechanical Properties Promotes Full-Thickness Skin Defect Healing by Regulating Immunomodulation and Angiogenesis Through Paracrine Secretion

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Engineering 2024年第6期37卷 138-151页

作者： Peng Wang liping Qian Huixin liang Jianhao Huang Jing Jin Chunmei Xie Bin Xue Jiancheng Lai yibo Zhang lifeng Jiang Lan li Qing Jiang State Key Laboratory of Pharmaceutical Biotechnology Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing UniversityNanjing 210008China Jiangsu Engineering Research Center for 3D Bioprinting Nanjing 210008China Institute of Medical 3D Printing Nanjing UniversityNanjing 210093China Centre for Experimental Animals Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing UniversityNanjing 210008China College of Aeroplane Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China National Laboratory of Solid State Microstructures Department of PhysicsNanjing UniversityNanjing 210093China Department of Chemical Engineering Stanford UniversityStanfordCA 94305USA Department of Orthopedic Surgery The Second Affiliated Hospital Zhejiang University School of MedicineOrthopedic Research Institute of Zhejiang UniversityKey Laboratory of Motor System Disease Research and Precision Therapy of Zhejiang ProvinceHangzhou 310009China

Hydrogel-based tissue-engineered skin has attracted increased attention due to its potential to restore the structural integrity and functionality of ***,the mechanical properties of hydrogel scaffolds and natural skin are substantially ***,we developed a polyvinyl alcohol(PVA)/acrylamide based interpenetrating network(IPN)hydrogel that was surface modified with polydopamine(PDA)and termed *** Dopa-gel exhibited mechanical properties similar to native skin tissue and a superior ability to modulate paracrine ***,a tough scaffold with tensile resistance was fabricated using this hydrogel by three-dimensional *** results showed that the interpenetration of PVA,alginate,and polyacrylamide networks notably enhanced the mechanical properties of the *** modification with PDA endowed the hydrogels with increased secretion of immunomodulatory and proangiogenic *** an in vivo model,Dopa-gel treatment accelerated wound closure,increased vascularization,and promoted a shift in macrophages from a proinflammatory M1 phenotype to a prohealing and anti-inflammatory M2 phenotype within the wound ***,the focal adhesion kinase(FAK)/extracellular signal-related kinase(ERK)signaling pathway may mediate the promotion of skin defect healing by increasing paracrine secretion via the ***,proangiogenic factors can be induced through Rho-associated kinase-2(ROCK-2)/vascular endothelial growth factor(VEGF)-mediated paracrine secretion under tensile stress *** together,these findings suggest that the multifunctional Dopa-gel,which has good mechanical properties similar to those of native skin tissue and enhanced immunomodulatory and angiogenic properties,is a promising scaffold for skin tissue regeneration.

关键词： Polyvinyl alcohol/acrylamide hydrogel Mechanical property enhancement Paracrine effect Skin regeneration Signaling pathways

Numerical study on waste polyethylene pyrolysis driven by self-sustaining smoldering

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Science China(Technological Sciences) 2024年第2期67卷 627-638页

作者： PAN RuMing WU yibo GUENE LOUGOU Bachirou SHUAI Yong DEBENEST Gérald School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institut de Mecanique des Fluides de Toulouse(IMFT)-Universite de Toulouse CNRS-INPT-UPSToulouse 31400France

Polyethylene is the type of waste plastic that accounts for the most significant proportion of municipal solid *** polyethylene can be valorized via pyrolysis and produce value-added oil,gas,and *** the other hand,self-sustaining smoldering is an emerging technical means to deal with sand/soil contaminated by organic *** high-temperature heat generated by smoldering can be used as a heat source for pyrolyzing waste ***,this study investigates numerically the pyrolysis of waste polyethylene driven by self-sustaining smoldering.A novel 4-step lumped kinetic model is proposed for simulating the pyrolysis of waste *** results indicate that the operating parameters can determine the pyrolysis product yields by regulating the pyrolysis temperature and the volatile residence *** that higher temperatures and longer residence times favor the generation of shorter-chain pyrolysis products because of the intensified volatiles’secondary *** can be concluded that a high interface-wall heat transfer coefficient(400 W m^(-2)K^(-1)),a low PE content(0.20),a high char concentration(2.4%),and a moderate air velocity(0.040 m s^(-1))are beneficial to oil *** some extent,this study may broaden the boundaries for the application of self-sustained smoldering-driven pyrolysis.

关键词： self-sustained smoldering waste polyethylene thermal decomposition oil production waste valorization

Arbuscular mycorrhizal fungi reduce ammonia emissions under different land-use types in agro-pastoral areas

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Pedosphere 2024年第2期34卷 497-507页

作者： Huaisong WANG Rui GUO yibo TIAN Nan CUI Xinxin WANG Lei WANG Zhongbao YANG Shuying li Jixun GUO lianxuan SHI Tao ZHANG Institute of Grassland Science Northeast Normal UniversityKey Laboratory of Vegetation EcologyMinistry of EducationJilin Songnen Grassland Ecosystem National Observation and Research StationChangchun 130024China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesKey Laboratory of Dryland AgricultureMinistry of AgricultureBeijing 100081China Mountainous Area Research Institute of Hebei Province Hebei Agricultural UniversityBaoding 071001China College of Agronomy Liaocheng UniversityLiaocheng 252059China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life ScienceShandong UniversityQingdao 266237China Forestry and Grassland Bureau of Aohan Banner Chifeng 024005China

Ammonia(NH3)emissions,the most important nitrogen(N)loss form,always induce a series of environmental problems such as increased frequency of regional haze pollution,accelerated N deposition,and N *** mycorrhizal(AM)fungi play key roles in N ***,it is still unclear whether AM fungi can alleviate N losses by reducing *** potential mechanisms by which AM fungi reduce NH_(3)emissions in five land-use types(grazed grassland,mowed grassland,fenced grassland,artificial alfalfa grassland,and cropland)were explored in this *** showed that AM fungal inoculation significantly reduced NH3emissions,and the mycorrhizal responses of NH3emissions were determined by land-use *** equation modeling(SEM)showed that AM fungi and land-use type directly affected NH_(3)*** addition,the reduction in NH_(3)emissions was largely driven by the decline in soil NH_(4)^(+)-N and pH and the increases in abundances of ammonia-oxidizing archaea(AOA)amoA and bacteria(AOB)amoB genes,urease activity,and plant N uptake induced by AM fungal inoculation and land-use *** present results highlight that reducing the negative influence of agricultural intensification caused by land-use type changes on AM fungi should be considered to reduce N losses in agriculture and grassland ecosystems.

关键词： agricultural intensification grassland management functional genes plant N uptake N leaching N loss

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印度“重新重视”孟加拉湾:举措与制约

国际问题研究 2020年第6期 94-114,138,139页

作者：李益波北京印刷学院马克思主义学院

近年来,孟加拉湾在印度战略布局中的地位明显提升。印度与沿岸国家在高层互访、互联互通、安全合作及人文交流等领域取得突破。印度试图通过整合"邻国优先"和"东向行动"政策、提升与孟加拉湾沿岸国家的双边关系、推动并领导地区合作机... 详细信息

近年来,孟加拉湾在印度战略布局中的地位明显提升。印度与沿岸国家在高层互访、互联互通、安全合作及人文交流等领域取得突破。印度试图通过整合"邻国优先"和"东向行动"政策、提升与孟加拉湾沿岸国家的双边关系、推动并领导地区合作机制建设、积极提供区域公共产品、强化军事安全存在、改善区域互联互通水平、加强同域外国家的伙伴关系等措施,重塑孟加拉湾战略秩序,恢复和巩固印度传统优势地位。印度"重新重视"孟加拉湾的动力不仅与该地区地缘战略环境的巨大变化有关,也与印度自身的战略文化、实力变化、利益需求和威胁认知有着密切关系。尽管受制于自身实力、域内国家互信水平和域外大国介入博弈的不确定性等因素,但在可预见的一段时期内,印度在孟加拉湾地区的基础设施投入、海洋安全合作及多边机制建设方面还会继续发力,这将给环孟加拉湾地区安全秩序及"一带一路"倡议扎根当地带来多重影响。

关键词：印度孟加拉湾印度外交南亚形势

美国强化环孟加拉湾地区政策:措施、动因及影响

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太平洋学报 2020年第7期28卷 41-53页

作者：李益波北京印刷学院马克思主义学院北京102600

自特朗普政府提出印太地区的战略愿景以来,孟加拉湾对美国的重要性进一步显现。美国不断加大对该地区外交、安全方面的投入,试图通过采取离岸平衡战略,在保持其优势地位的基础上,推动印度扮演“责任承担者”角色,自己居于幕后成为保证... 详细信息

自特朗普政府提出印太地区的战略愿景以来,孟加拉湾对美国的重要性进一步显现。美国不断加大对该地区外交、安全方面的投入,试图通过采取离岸平衡战略,在保持其优势地位的基础上,推动印度扮演“责任承担者”角色,自己居于幕后成为保证区域安全的支配性力量。同时,美国还试图在该地区拓展伙伴关系,参与地区机制建设,运用排他性制度制衡策略阻挠中国在区域内的制度建设努力。美国在该地区采取的疏离或针对中国的举措明显出于“大国竞争”的战略考虑,这必然会压缩两国维护共同海洋利益的合作空间。同时,“下注印度”会诱导印度在孟加拉湾采取强势海洋政策,最终导致中印美在该地区的战略互动朝对抗性方向发展,干扰地区安全治理模式的选择与进程。美国在环孟加拉湾地区的政策调整能否达到其预期目的,还将受到自身实力相对衰落、印度的态度及区域内中小国家外交决策偏好等多重因素的制约。

关键词：孟加拉湾海洋安全大国竞争离岸平衡战略

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柱塞副温度场数学建模与性能分析

中南大学学报（自然科学版） 2018年第2期49卷 330-338页

作者：马俊李毅波潘阳中南大学机电工程学院湖南长沙410083 中南大学高性能复杂制造国家重点实验室湖南长沙410083

为完善轴向柱塞泵柱塞副性能分析理论体系,针对温度分布影响柱塞副性能问题进行研究,建立瞬时油膜厚度场、压力场和温度场模型以及柱塞副摩擦与泄漏模型,采用交错网格技术划分油膜网格,采用有限体积法求解能量方程和雷诺方程,以MATLAB... 详细信息

为完善轴向柱塞泵柱塞副性能分析理论体系,针对温度分布影响柱塞副性能问题进行研究,建立瞬时油膜厚度场、压力场和温度场模型以及柱塞副摩擦与泄漏模型,采用交错网格技术划分油膜网格,采用有限体积法求解能量方程和雷诺方程,以MATLAB仿真软件为依托耦合各物理场模型和柱塞微运动特性,对柱塞副动态温度场进行数值求解。研究温度对油膜压力分布、柱塞副轴向摩擦力和泄漏量的影响,并分析油膜不同入口温度对柱塞副性能参数的影响规律。研究结果表明:温度变化数值计算结果与实验结果基本一致;在柱塞副中引入动态温度后油膜压力峰值明显降低,轴向摩擦力有所下降,但柱塞副泄漏量增加较快;控制油膜入口油温能有效提高柱塞副工作性能。

关键词：柱塞副温度场泄漏量数值计算