Two-dimensional plane strain consolidation of unsaturated soils considering the depth-dependent stress

In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress diffusion on the two-dimensional(2D)plane strain consolidation properties of unsaturated soils when the stress varies with time and depth.A series of semi-analytical solutions in terms of excess pore air and water pressures and settlement for 2D plane strain consolidation of unsaturated soils can be derived with the joint use of Laplace transform and Fourier sine series expansion.Then,the inverse Laplace transform of the semi-analytical solution is given in the time domain using a self-programmed code based on Crump’s method.The reliability of the obtained solutions is proved by the degeneration.Finally,the 2D plots of excess pore pressures and the curves of settlement varying with time,considering different physical parameters of unsaturated soil stratum and depth-dependent stress,are depicted and analyzed to study the 2D plane strain consolidation properties of unsaturated soils subjected to the depthdependent stress.

On Boolean elements and derivations in 2-dimension linguistic lattice implication algebras

A 2-dimension linguistic lattice implication algebra(2DL-LIA)can build a bridge between logical algebra and 2-dimension fuzzy linguistic information.In this paper,the notion of a Boolean element is proposed in a 2DL-LIA and some properties of Boolean elements are discussed.Then derivations on 2DL-LIAs are introduced and the related properties of derivations are investigated.Moreover,it proves that the derivations on 2DL-LIAs can be constructed by Boolean elements.

茄衣新品系川雪2号全国多点试验研究

为雪茄烟茄衣新品系川雪2号的品种审定、推广提供科学依据。以川雪2号及其他8份雪茄烟品系为试验材料,2021年在全国9个主要雪茄烟产区、2022年在全国8个主要雪茄烟产区开展多点试验。结果表明,川雪2号田间整齐、长势强,大田生育期88 d、免疫TMV、抗根黑腐病、综合抗病能力较强、田间自然发病率整体较轻;平均产量为1533.30 kg/hm^(2),平均产值为83234.70元/hm^(2),中上等烟比例为74.98%,产量、产值、中上等烟比例、评吸总分等在9个参试品系中排名靠前。川雪2号总体表现较好,可以进行一定规模的示范种植并开展相关配套栽培技术研究。

2型糖尿病老年病人心肌纤维化T1-Mapping与左心室应变参数的相关性分析

目的探究2型糖尿病(T2DM)老年病人心肌纤维化T1-Mapping参数与左心室应变参数之间的相关性。方法以2019年8月至2022年8月在孝感市中心医院就诊的T2DM病人82例为研究对象,根据病人的病程分为短期T2DM组40例(病程<5年)和长期T2DM组42例(病程≥5年),以同期招募的健康志愿者40例为对照组。比较各组间左心室应变参数及T1-Mapping参数。采用多元线性逐步回归法分析T1-Mapping参数的影响因素。采用相关性分析T1-Mapping参数与左心室应变参数的相关性。结果短期T2DM组病人左室周向峰值舒张应变率(PDSR)[1.25(0.95,1.50)1/s比1.40(1.20,1.70)1/s]较对照组降低(P<0.05),细胞外体积(ECV)[31.00(29.00,33.50)%比29.00(27.00,32.00)%]较对照组升高(P<0.05)。与对照组比较,长期T2DM组病人左室纵向峰值应变(PS)[−14.50(−12.38,−16.50)%比−16.15(−14.60,−18.30)%]、径向PDSR[(−2.58±0.83)1/s比(−3.32±0.88)1/s]、周向PDSR[0.90(0.70,1.20)1/s比1.40(1.20,1.70)1/s]、纵向PDSR[0.70(0.58,0.90)1/s比1.10(0.80,1.38)1/s]降低(P<0.05),ECV[34.00(32.00,35.00)%比29.00(27.00,32.00)%]升高(P<0.05)。与短期T2DM组比较,长期T2DM组病人左室纵向PS[−14.50(−12.38,−16.50)%比−16.15(−14.45,−18.38)%]、径向PDSR[(−2.58±0.83)1/s比(−3.61±0.76)1/s]、周向PDSR[0.90(0.70,1.20)1/s比1.25(0.95,1.50)1/s]、纵向PDSR[0.70(0.58,0.90)1/s比1.10(0.80,1.30)1/s]降低(P<0.05),ECV[34.00(32.00,35.00)%比31.00(29.00,33.50)%]升高(P<0.05)。多元线性回归分析结果示,糖尿病病程是T2DM病人ECV的独立影响因素(β=0.29,P<0.05)。Spearman相关性分析结果示,T2DM病人ECV与左室纵向PS(r_(s)=0.35,P<0.05)、纵向峰值收缩应变率(PSSR)(r_(s)=0.31,P<0.05)呈显著正相关,与左室周向PDSR(r_(s)=−0.29,P<0.05)、纵向PDSR(r_(s)=−0.43,P<0.05)呈显著负相关。结论心脏磁共振T1-Mapping可能发现T2DM病人早期心肌纤维化,T1-Mapping参数与左心室应变参数显著相关。

考虑超临界CO_(2)损伤的椭球形三维裂缝计算新模型

目前超临界CO_(2)压裂研究成果多集中于室内岩石损伤机理和劣化力学参数测试,对压裂形成的三维裂缝形态研究较少。为刻画超临界CO_(2)压裂过程的裂缝形态展布,基于Griffith断裂力学理论,建立了平面应变条件下椭球形裂缝扩展的三维计算新模型;结合前人室内测试结果,回归了岩石弹性力学参数与超临界CO_(2)多浸泡因素关联式,讨论了超临界CO_(2)压力、温度、施工排量、初始弹性模量、初始泊松比、缝内净压力、储层厚度等参数对裂缝扩展形态的影响。结果表明:针对上下存在水层的目的层采用超临界CO_(2)压裂时更应采取控缝高的措施;针对低渗储层,可优先考虑超临界CO_(2)压裂;超临界CO_(2)压裂工艺更适用于最小水平主应力大的储层;超临界CO_(2)压裂时,有助于低排量下获得相同的平均缝宽。研究成果对非常规油气水平井超临界CO_(2)压裂裂缝参数优化具有重要意义。

SARS-CoV-2重组痘苗病毒疫苗rVTT△TK-RBD的构建、筛选及免疫原性研究

目的 构建重组痘苗病毒载体疫苗rVTT△TK-RBD,并评价其安全性和免疫原性。方法 参考严重急性呼吸综合征冠状病毒2(SARS-CoV-2)基因序列合成受体结合域(RBD)基因,并将其插入自主构建的重组质粒pSTKE的多克隆位点上,构建重组痘苗病毒穿梭载体pSTKE-RBD,并转染到预先感染天坛株痘苗病毒(VTT)的BHK-21细胞内,经多轮的荧光噬斑筛选成功获得重组痘苗病毒rVTT△TK-RBD;通过滴鼻方式免疫小鼠后,检测rVTT△TK-RBD对BALB/c小鼠体质量的影响;通过肌肉免疫小鼠后,分析rVTT△TK-RBD对BALB/c小鼠产生的特异性抗体和中和抗体的水平;通过流式细胞术检测rVTT△TK-RBD对BALB/c小鼠T细胞亚群的影响。结果 利用同源重组、增强型绿色荧光蛋白(EGFP)筛选标记和多次荧光噬斑筛选,成功筛选获得了表达RBD的胸腺激酶(TK)基因缺失型重组痘苗病毒rVTT△TK-RBD,且PCR验证成功。BALB/c小鼠体内实验表明rVTT△TK-RBD具有较好的抗SARS-CoV-2的免疫原性且相比于亲本株VTT明显降低了对机体的毒性作用。结论 成功构建并获得SARS-CoV-2重组痘苗病毒疫苗rVTT△TK-RBD并通过各项试验证明其安全性和免疫原性。

Multi-attribute group decision making method under 2-dimension uncertain linguistic variables

A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their fuzzy subjective evaluation information.Firstly,in order to measure the 2DULVs more accurately,a new method is proposed to compare two 2DULVs,called a score function,while a new function is defined to measure the distance between two 2DULVs.Secondly,two optimization models are established to determine the weight of experts and attributes based on the new distance formula and a weighted average operator is used to determine the comprehensive evaluation value of each alternative.Then,a score function is used to determine the ranking of the alternatives.Finally,the effectiveness of the proposed method is proved by an illustrated example.

‘红福瑞鲤2号’和‘福瑞鲤2号’稻田养殖生长性能对比

研究旨在评估‘红福瑞鲤2号’在福建山区稻田养殖的可行性,并与‘福瑞鲤2号’进行比较以确定其潜在的优势。于2023年8—10月,在武夷山市岚谷乡岚峰稻花鱼养殖基地进行了生长性能对比试验。采用同塘比较法对‘红福瑞鲤2号’和‘福瑞鲤2号’在投饵和不投饵稻田养殖模式下进行生长性能对比分析。经过60 d的养殖试验,结果显示,在相同沟凼式稻田养殖条件下,无论投饵与否,‘红福瑞鲤2号’的成活率、体质量绝对增长率、体质量相对增长率、体质量特定生长率和产量均明显低于‘福瑞鲤2号’。投饵养殖模式下‘红福瑞鲤2号’和‘福瑞鲤2号’的体质量绝对增长率、体质量相对增长率、体质量特定生长率、体长绝对增长率、体长相对增长率和体长特定生长率均明显高于不投饵养殖模式;而在不投饵养殖模式下,‘红福瑞鲤2号’终末和初始平均体质量、平均体长均不存在显著差异。综上所述,初步研究结果表明,在当前的武夷山山区稻田养殖条件下,‘红福瑞鲤2号’相较于‘福瑞鲤2号’并没有表现出生长优势。这一发现为该地区稻田养殖鱼类品种的选择提供了试验参考。

松辽盆地深部基底地应力状态:来自松科2井地应力实测数据的证据

松辽盆地基底内的地应力状态是地震等地质灾害研究、盆地动力学分析和油气资源开发利用等领域的重要基础数据。岩心非弹性应变恢复法是近年来发展起来的基于钻孔岩心的近原位三维地应力测量方法。本文将岩心非弹性应变恢复法应用于松辽盆地大陆科学钻探松科2井(SK-2)深部地应力测量,获得了松辽盆地基底内近6~7 km的三维地应力状态,结果表明盆地基底内(6646~6846 m)为走滑断层应力环境(σ_(H)>σ_(V)>σ_(h)),最大水平主应力方向为近E-W方向。盆地基底内的应力状态与盆地内及周边邻近区域的震源机制解(震源深度7~15 km)所反演的应力环境相吻合。盆地基底处于以E-W向近水平挤压为主导的构造应力场,这种应力状态的形成,可能为西太平洋板块NW向挤压运动背景下,受控于NE-NEE走向的依兰—伊通断裂和敦化—密山断裂右行走滑产生的次级应力场。研究结果对于认识区域构造应力场背景及松辽盆地的形成与演化过程具有重要参考价值。

2'⁃岩藻糖基乳糖功能及其微生物生产菌种构建研究进展

2'⁃岩藻糖基乳糖(2'⁃fucosyllactose,2'⁃FL)在人乳寡糖中含量最高,占比可达30%。2'⁃FL能够有效促进婴儿大脑发育、提高婴儿免疫力,对青少年、成年人、老年人也大有裨益,已被广泛应用于婴幼儿配方奶粉、功能性食品饮料及医疗辅剂中。微生物合成2'⁃FL具有易实现大规模生产、可使用廉价原料作为底物等优势。目前2'⁃FL最主要的工业生产菌种为大肠杆菌,其他食品安全级菌株如酿酒酵母、枯草芽孢杆菌等也陆续被改造用来生产2'⁃FL,并已取得一定成效。该文对2'⁃FL作用于人体的机制、应用领域及2'⁃FL合成菌种构建现状等进行综述,并对未来发展趋势进行展望。

左心自动应变分析评价高脂血症对2型糖尿病患者左心功能的影响

目的 分应用左心自动应变分析评价2型糖尿病(T2DM)患者的左心功能,旨在验证高脂血症是否加剧T2DM患者左心功能障碍,并探讨与左心应变相关的危险因素。方法 选取86例T2DM患者,根据是否合并高脂血症分为DM1组(不合并高脂血症,n=43)和DM2组(合并高脂血症,n=43)。另选取43例健康志愿者作为对照组。对所有入组人员进行常规超声心动图和左心自动应变分析检查,获取常规超声测量值和左心室心尖四腔心整体纵向应变(GLSA4c)、左心室心尖三腔心整体纵向应变(GLSA3C)、左心室心尖两腔心整体纵向应变(GLSA2C)、左心室平均整体纵向应变(GLSavg)、左房储存应变(LASr)、左房通道应变(LAScd)、左房收缩应变(LASct)。比较各组间观察指标的差异,采用多元线性回归分析确定影响左心应变的独立危险因素。结果 与对照组相比,DM1组LVGLSA4C、LVGLSA3C、LVGLSA2C、LVGLSavg、LASr、LAScd明显减低(P<0.05)。DM2组LVGLSA4C、LVGLSA3C、LVGLSA2C、LVGLSavg、LASr、LAScd均低于其他两组(P<0.05)。预估总胆固醇与左心LVGLSA4C、LVGLSA3C、LVGLSA2C、LVGLSavg、LASr、LAScd绝对值呈负相关关系(P<0.001),甘油三酯与左心LVGLSA4C、LVGLSA3C、LVGLSA2C、LVGLSavg、LASr、LAScd绝对值呈负相关关系(P<0.001)。多元线性回归分析显示,LVGLSA4C、LVGLSA3C、LVGLSA2C、LVGLSavg、LASr、LAScd绝对值与TG独立相关(P<0.05)。结论 T2DM患者的左心应变明显受损,高脂血症可加剧糖尿病患者左心应变的恶化。TG可能是预测左心应变减低的独立危险因素。

Multisoliton Solutions of the (2+1)-Dimensional KdV Equation

Using the extension homogeneous balance method,we have obtained some new special types of soliton solutions of the (2+1)-dimensional KdV equation.Starting from the homogeneous balance method,one can obtain a nonlinear transformation to simple (2+1)-dimensional KdV equation into a linear partial differential equation and two bilinear partial differential equations.Usually,one can obtain only a kind of soliton-like solutions.In this letter,we find further some special types of the multisoliton solutions from the linear and bilinear partial differential equations.

左室压力-应变环评估肥胖2型糖尿病患者左室收缩功能的临床价值

目的探讨左室压力-应变环评估肥胖2型糖尿病(T2DM)患者左室收缩功能的临床应用价值。方法选取我院收治的T2DM患者84例,根据体质量指数(BMI)分为T2DM伴肥胖组41例(BMI≥25 kg/m^(2))和T2DM不伴肥胖组43例(BMI<25 kg/m^(2)),均行常规超声心动图和左室压力-应变环检查并获取相关参数,比较两组各参数的差异。采用多因素Logistic回归分析筛选肥胖T2DM患者左室收缩功能受损的独立影响因素;分析肥胖T2DM患者GLS和心肌做功参数与BMI的相关性。结果两组常规超声心动图参数比较差异均无统计学意义。T2DM伴肥胖组整体纵向应变(GLS)、整体有效功(GCW)、整体做功效率(GWE)均低于T2DM不伴肥胖组,整体无效做功(GWW)、整体做功指数(GWI)均高于T2DM不伴肥胖组,差异均有统计学意义(均P<0.05)。多因素Logistic回归分析显示,BMI、GWW、GWI均为肥胖T2DM患者左室收缩功能受损的独立危险因素(OR=1.973、1.619、1.748,均P<0.05),GLS、GCW、GWE均为独立保护因素(OR=0.847、0.814、0.781,均P<0.05)。肥胖T2DM患者GWI、GWW与BMI均呈正相关(r=0.673、0.633,均P<0.001),GLS、GCW、GWE与BMI均呈负相关(r=-0.611、-0.597、-0.681,均P<0.001)。结论肥胖可能会加重T2DM患者左室重构和收缩功能受损,左室压力-应变环在评估肥胖T2DM患者左室收缩功能中具有一定的临床应用价值。

新型简化胰岛素抵抗评价指标对T2DM患者左心室亚临床收缩功能受损的预测价值

目的分析新型简化胰岛素抵抗评价指标对2型糖尿病(T2DM)患者左心室亚临床收缩功能受损的预测价值。方法收集2021年6-12月就诊于空军军医大学第一附属医院内分泌科的150例左心室射血分数(LVEF)≥50%的T2DM患者进行回顾性分析。所有患者均接受二维斑点追踪超声心动图检查,并测量左心室整体纵向应变(GLS)。将受试者根据GLS值分为左心室亚临床收缩功能正常组(GLS≥18%组,n=80)与左心室亚临床收缩功能受损组(GLS<18%组,n=70)。此外,计算体重指数(BMI)、三酰甘油/高密度脂蛋白胆固醇比值(TG/HDL-C比值)、TG-葡萄糖(TyG)指数、TyG-BMI指数(TyG-BMI)、TyG-WHR指数(TyG-WHR)、胰岛素抵抗代谢指数(METS-IR),作为新型简化胰岛素抵抗评价指标,并进行两组间比较。采用Pearson相关分析法分析简化胰岛素抵抗评价指标与GLS的相关性。采用受试者工作特征(ROC)曲线下面积(AUC)评估新型简化胰岛素抵抗评价指标对GLS<18%人群的诊断效能。基于高血压分层的二元logistics回归分析简化胰岛素抵抗评估指标与GLS<18%的独立相关性。结果150例患者年龄(54.5±13.7)岁,其中男96例(64.0%),女54例(36.0%)。与GLS≥18%组比较,GLS<18%组患者的TG/HDL-C比值、Ty G指数、Ty G-BMI、METS-IR均明显增高,差异有统计学意义(P<0.05)。Pearson相关分析显示,TG/HDL-C比值、Ty G指数、Ty G-BMI、Ty G-WHR、METS-IR均与GLS呈负相关(P<0.05)。ROC曲线分析显示,Ty G指数对评价GLS<18%具有一定的预测价值(AUC=0.678,95%CI 0.591~0.765,P<0.001)。基于高血压分层且校正混杂因素后,二元logistics回归分析显示,Ty G指数与GLS<18%独立相关(OR=3.249,95%CI 1.045~10.103,P=0.042)。结论新型简化胰岛素抵抗评价指标与T2DM患者左心室亚临床收缩功能受损密切相关。TyG指数是识别该人群左心室亚临床收缩功能受损的有效指标。

二维斑点追踪分层应变技术对不同体质量指数2型糖尿病患者左心室收缩功能的评价

目的:应用二维斑点追踪(two-dimensional speckle tracking imaging,2D-STI)分层应变技术评价不同BMI的2型糖尿病(type 2 diabetes mellitus,T2DM)患者左心室纵向分层应变,以了解不同BMI对T2DM患者左心室收缩功能的影响。方法:入选2021年1月至2023年3月,就诊于开州区人民医院,初次诊断为T2DM的患者102例,根据不同BMI分为三组,正常体质量组(18.5 kg/m^(2)≤BMI≤24 kg/m^(2)),超质量组(24 kg/m^(2)<BMI<28 kg/m^(2))肥胖组(BMI≥28 kg/m^(2))。所有患者均连接心电模拟信号,采集常规超声心动图二维参数同时应用2D-STI分层应变技术获得左心室整体纵向收缩峰值应变(global longitudinal strain,GLS)、左室心内膜下纵向应变(longitudinal peak strain of subendocardial myocardial,LPSEndo)、中层纵向应变(longitudinal peak strain of middle myocardia,LPSMid)及心外膜下心肌纵向应变(longitudinal peak strain of subepicardial myocardial,LPSEpi)。比较各组超声心动图常规二维参数及应变间的差异。结果:从正常体质量组、超质量组到肥胖组GLS、LPSEndo、LPSMid、LPSEpi的绝对值逐渐减低(F=20.574、60.375、5.964、20.383,P<0.05),差异有统计学意义(P<0.05)。与正常体质量组相比,超质量组GLS、LPSEndo、LPSMid、LPSEpi的绝对值减低,差异有统计学意义(P<0.05)。与超质量组相比,肥胖组GLS、LPSEndo、LPSMid、LPSEpi的绝对值减低,差异有统计学意义(P<0.05)。ROC曲线显示LPSEndo诊断左心室收缩障碍的曲线下面积(AUC=91.2%,95%CI:0.840~0.959),最佳诊断界值为-21.9%,敏感度为66.7%,特异度为100%(P<0.05)。结论:2D-STI分层应变技术可定量分析不同BMI对T2DM患者左心室收缩功能的影响,为临床诊断及治疗提供质量要依据。

应变对析氢反应催化剂TiC_(2)性能影响的研究

应变工程是一种有效地用来调整原子薄膜材料的电子、磁性和光学性能的策略.利用第一性原理计算,我们表明应变也可以有效地调节Ti C_(2)的析氢反应(HER)的催化活性,这是电解水电化学制氢所必需的.我们主要考虑0-8%范围的拉伸应变,研究发现,在25%的氢覆盖率下双轴拉伸比单轴拉伸能更有效的提高HER活性,但b方向拉伸后的Ti C_(2)结构具有更高的氢最大覆盖率,且b方向的拉伸应变对不同氢覆盖率的Ti C_(2)单层片的催化性能都有很大的提高.电子结构计算表明,拉伸应变可以激活相对惰性的内部价电子,从而引起体系的失稳和催化活性的提高.在本工作中获得的见解可能有助于利用应变作为一种有效手段来提高二维材料的催化活性,并探索更有效地调整其电子结构和催化活性的新方法.

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2) thin films

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CMOS)technology.However,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin films.Fortunately,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress engineering.In this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented Si substrate has been reported.Structural analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin films.In addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been obtained.The results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

Subclinical impairment of left ventricular myocardium function in type 2 diabetes mellitus patients with or without hypertension

BACKGROUND Cardiovascular disease has been the leading cause of morbidity and mortality for type 2 diabetes mellitus(T2DM)patients over the last decade.AIM To determine whether layer-specific global longitudinal strain(GLS)combined with peak strain dispersion(PSD)can be used to assess left ventricle(LV)myocardium systolic dysfunction in T2DM patients or without hypertension(HP).METHODS We enrolled 97 T2DM patients,70 T2DM+HP patients and 101 healthy subjects.Layer-specific GLS and PSD were calculated by EchoPAC software in apical three-,four-and two-chamber views.GLS of the epimyocardial,middle-layer and endomyocardial(GLSepi,GLSmid,and GLSendo)were measured and recorded.Receiver operating characteristic analysis was performed to detect LV myocardium systolic dysfunction in T2DM patients.RESULTS There were significant differences in GLSepi,GLSmid,GLSendo,and PSD between healthy subjects,T2DM patients and T2DM patients with HP(P<0.001).Trend tests yielded the ranking of healthy subjects>T2DM patients>T2DM with HP patients in the absolute values of GLSepi,GLSmid and GLSendo(P<0.001),while PSD was ranked healthy subjects<T2DM<T2DM with HP(P<0.001).Layer-specific GLS and PSD had high diagnostic efficiency for detecting LV myocardium systolic dysfunction in T2DM patients,however,the area under the curve(AUC)for layer-specific GLS and PSD combined was significantly higher than the AUCs for the individual indices(P<0.05).CONCLUSION Layer-specific GLS and PSD were associated with LV myocardium systolic dysfunction in T2DM patients,T2DM patients with HP.T2DM patients with HP have more severe LV myocardium systolic dysfunction than T2DM patients without HP and normal control patients.The combination of layer-specific GLS and PSD may provide additional prognostic information for T2DM patients with or without HP.

Evaluation of left ventricular systolic function in type 2 diabetes mellitus patients with and without peripheral vascular disease

BACKGROUND Peripheral vascular disease(PVD)is a common complication of type 2 diabetes mellitus(T2DM).Patients with T2DM have twice the risk of PVD as nondiabetic patients.AIM To evaluate left ventricular(LV)systolic function by layer-specific global longitudinal strain(GLS)and peak strain dispersion(PSD)in T2DM patients with and without PVD.METHODS Sixty-five T2DM patients without PVD,57 T2DM patients with PVD and 63 normal controls were enrolled in the study.Layer-specific GLS[GLS of the epimyocardium(GLSepi),GLS of the middle myocardium(GLSmid)and GLS of the endocardium(GLSendo)]and PSD were calculated.Receiver operating characteristic(ROC)analysis was performed to calculate the sensitivity and specificity of LV systolic dysfunction in T2DM patients with PVD.We calculated Pearson’s correlation coefficients between biochemical data,echocardiographic characteristics,and layer-specific GLS and PSD.RESULTS There were significant differences in GLSepi,GLSmid and GLSendo between normal controls,T2DM patients without PVD and T2DM patients with PVD(P<0.001).Trend tests revealed a ranking of normal controls>T2DM patients without PVD>T2DM patients with PVD in the absolute value of GLS(P<0.001).PSD differed significantly between the three groups,and the trend ranking was as follows:normal controls<T2DM patients without PVD<T2DM patients with PVD(P<0.001).ROC analysis revealed that the combination of layer-specific GLS and PSD had high diagnostic efficiency for detecting LV systolic dysfunction in T2DM patients with PVD.Lowdensity lipoprotein cholesterol was positively correlated with GLSepi,GLSmid and PSD(P<0.05),while LV ejection fraction was negatively correlated with GLSepi,GLSmid and GLSendo in T2DM patients with PVD(P<0.01).CONCLUSION PVD may aggravate the deterioration of LV systolic dysfunction in T2DM patients.Layer-specific GLS and PSD can be used to detect LV systolic dysfunction accurately and conveniently in T2DM patients with or without PVD.

2型糖尿病对非缺血性扩张型心肌病患者左心室应变影响

目的:采用心脏磁共振特征追踪技术(CMR-FT)定量及延迟钆增强(LGE)特征定量、定性评估2型糖尿病(T2DM)对非缺血性扩张型心肌病(NIDCM)患者左室应变及组织特征的影响。方法:回顾性纳入行CMR检查的38例NIDCM患者及20名健康对照者,将NIDCM根据有无T2DM病史分为两组,比较三组间一般临床资料、左室结构及功能、应变参数及两组NIDCM患者的组织特征差异,并通过一元线性回归分析判断NIDCM患者左室心肌应变的临床重要预测因子。结果:NIDCM(T2DM+)组HbA1c、高血压患病率均高于NIDCM(T2DM-)组及对照组,差异具有统计学意义(P<0.05)。NIDCM(T2DM+)组心尖部周向及纵向应变、整体周向应变均较NIDCM(T2DM-)组降低,差异具有统计学意义(P<0.05)。两组NIDCM患者的LGE特征差异均无统计学意义。在一元线性回归分析中T2DM为NIDCM患者左室整体周向(β=0.35,P=0.031)及纵向应变(β=0.354,P=0.029)降低的重要临床预测因子。结论:CMR-FT技术可准确评估合并T2DM的NIDCM患者左室应变下降,且T2DM与NIDCM患者左室整体周向及纵向应变的降低显著相关。