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Conductivity characteristics of landslide considering porosity,saturation,temperature and ion concentration

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Journal of Mountain Science 2023年第8期20卷 2133-2148页

作者： XIONG Bo-bo YANG Shi-jie ZHAO Bing-qin lu xiao-chun TIAN Bin LI Cheng WU Xuan-xuan TU xiao-long College of Hydraulic and Environmental Engineering China Three Gorges UniversityYichang 443000China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443000China Hubei Energy Group luotian Pingtanyuan Pumped Storage Co. Ltd.Huanggang 438000China

High-density resistivity imaging method is widely used in landslide *** resistivity of rock and soil is closely related to factors,such as porosity,moisture content,saturation and *** this study,the resistivity test was designed to investigate the influence of physical factors and pore solution components on the resistivity of landslide *** and analytical results find that both moisture content and volumetric water content varies greatly under the same *** different temperatures,soil resistivity exhibits great *** the same temperature,the ion concentration and species in pore solutions have great influence on soil *** on the test results and grey correlation analysis,this study established a resistivity model by considering porosity,saturation,temperature and ion *** study lays a foundation for the high-density resistivity method to measure the moisture content of landslides.

关键词： Landslide monitoring High-density resistivity method Pore fluid composition Resistivity model

Improvement in cardiac function after sarcoplasmic reticulum Ca^2＋-ATPase gene transfer in a beagle heart failure model

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Chinese Medical Journal 2009年第12期122卷 1423-1428页

作者： MI Ya-fei LI xiao-ying TANG Li-jiang lu xiao-chun FU Zhi-qing YE Wei-hua Department of Cardiology Taizhou Hospital of Zhejiang Province Wenzhou Medical College Linhai Zhejiang 317000 China Department of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Department of Cardiac Surgery Chinese PLA General Hospital Beijing 100853 China

Background Heart failure （HF） is a major cause of morbidity and mortality worldwide, but current treatment modalities cannot reverse the underlying pathological state of the heart. Gene-based therapies are emerging as promising therapeutic modalities in HF patients. Our previous studies have shown that recombinant adeno-associated viral （rAAV） gene transfer of Sarco-endoplasmic reticulum calcium ATPase （SERCA2a） can be effective in treating rats with chronic heart failure （CHF）. The aim of this study was to examine the effects of SERCA2a gene transfer in a large HF animal model. Methods HF was induced in beagles by rapid right ventricular pacing （230 beats/min） for 30 days. A reduced rate ventricular pacing （180 beats/min） was continued for another 30 days. The beagles were assigned to four groups：（a） control group （n=4）; （b） HF group （n=4）; （c） enhanced green fluorescent protein group （n=4）; and （d） SERCA2a group （n=4）. rAAV1-EGFP （1×10^12 μg） and rAAV1-SERCA2a （1×10^12 μg） were delivered intramyocardially. SERCA2a expression was assessed by Western blotting and immunohistochemistry. Results Following 30 days of SERCA2a gene transfer in HF beagles its protein expression was significantly higher than in the HF group than in the control group （P 〈0.05）. Heart function improved along with the increase in SERCA2a expression. Left ventricular systolic function significantly improved, including the ejection fraction, left ventricular systolic pressure, maximal rate of rise of left ventricular pressure （＋dp/dtmax）, and the maximal rate of decline of left ventricular pressure （-dp/dtmax）（P 〈0.05）. Left ventricular end-diastole pressure significantly decreased （P 〈0.05）. The expression of SERCA2a in the myocardial tissue was higher in the SERCA2a group than in the HF group （P〈0.05）. Conclusions Intramyocardial injection of rAAV1-SERCA2a can improve the cardiac function in beagles induced with HE We expect further studies on SERCA2a＇s long-term safety, efficacy, dosage and

关键词： heart failure gene therapy sarco-endoplasmic reticulum calcium ATPase

Genome-wide association study for starch content and constitution in sorghum(Sorghum bicolor(L.) Moench)

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Journal of Integrative Agriculture 2019年第11期18卷 2446-2456页

作者： CHEN Bing-ru WANG chun-yu WANG Ping ZHU Zhen-xing XU Ning SHI Gui-shan YU Miao WANG Nai LI Ji-hong HOU Jia-ming LI Shu-jie ZHOU Yu-fei GAO Shi-jie lu xiao-chun HUANG Rui-dong College of Agronomy Shenyang Agricultural UniversityShenyang 110866P.R.China Molecular Improvement of Agricultural Crops Lab Liaoning Academy of Agricultural SciencesShenyang 110161P.R.China Institute of Crop Germplasm Resources Jilin Academy of Agricultural SciencesGongzhuling 136100P.R.China

Starch is the most important component in endosperm of sorghum ***,two types of starch are present:amylose(AM)and amylopectin(AP).The levels of AM and AP contents play a significant role in the appearance,structure,and quality of sorghum grains and in marketing *** the present study,a panel of 634 sorghum(Sorghum bicolor(L.)Moench)accessions were evaluated for starch,AM,and AP contents of grain,which included a mini core collection of 242 accessions from the International Crops Research Institute for the Semi-Arid Tropics(ICRISAT)in India,and 252 landraces and 140 cultivars from *** average starch content was 67.64%and the average AM and AP contents were 20.19 and 79.81%,*** developed a total of 260000 high-confidence single nucleotide polymorphism(SNP)markers in the panel of 634 accessions of *** using specific locus amplified fragment sequencing(SLAF-seq).We performed genome-wide association studies(GWAS)of starch,AM,and AM/AP of grain and SNP markers based on a mixed linear model(MLM).In total,70 significant association signals were detected for starch,AM,and AM/AP ratio of grain with P<4.452×10^-7,of which 10 SNPs were identified with significant starch,51 SNPs were associated with AM,and nine SNPs were associated with the AM/AP *** Gene Ontology(GO)analysis identified 12 candidate genes at five QTLs associated with starch metabolism within the 200-kb intervals,located on chromosomes 1,5,6,and *** these genes,Sobic.006G036500.1 encodes peptidyl-prolyl cis-trans-isomerase CYP38 responsible for hexose monophosphate shunt(HMS)and Sobic.009G071800 encodes 6-phospho-fructokinase(PFK),which is involved in the embden-meyerhof pathway(EMP).Kompetitive allele specific PCR(KASP)markers were developed to validate the GWAS *** C allele is correlated with a high starch content,while the T allele is linked with a low level of starch content,and provides reliable haplotypes for MAS in sorghum quality improvement.

关键词： sorghum genome-wide association mapping (GWAS) starch content amylose (AM) candidate genes KASP

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星间链路体制下的星地双向时间同步方法

宇航学报 2017年第7期38卷 728-734页

作者：吕宏春卢晓春武建锋中国科学院国家授时中心西安710600 中国科学院大学北京100049 中国科学院精密导航定位与定时技术重点实验室西安710600 中国科学院大学天文与空间学院北京101408 中国科学院大学电子电气与通信工程学院北京101408

推导了星地双向时间同步的数学模型,提出了在星间链路体制下进行星地双向时间同步的方法,计算了新一代导航试验卫星与西安站的相对钟差,通过对计算结果分别按1周、1天和1小时时长进行参数拟合,以及进行短期频率稳定度分析,验证了试验阶... 详细信息

推导了星地双向时间同步的数学模型,提出了在星间链路体制下进行星地双向时间同步的方法,计算了新一代导航试验卫星与西安站的相对钟差,通过对计算结果分别按1周、1天和1小时时长进行参数拟合,以及进行短期频率稳定度分析,验证了试验阶段星间链路体制下星地双向时间同步的精度和性能。结果表明,1周、1天和1小时的拟合时长星间链路体制下的星地时间同步精度分别达到了3.42纳秒、0.30纳秒和0.15纳秒,10000秒频率稳定度优于8×10^(-14)。

关键词：星间链路星地时间同步时分体制北斗卫星导航系统

GNSS导航信号常见畸变产生机理及对测距性能影响分析

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系统工程与电子技术 2015年第7期37卷 1611-1620页

作者：贺成艳郭际卢晓春卢鋆中国科学院国家授时中心陕西西安710600 中国科学院精密导航定位与定时重点实验室陕西西安710600 北京跟踪与通信技术研究所北京100049

在全球卫星导航系统(global navigation satellite system,GNSS)导航信号的产生、发射、传播和接收过程中各种环节的异常,都有可能对卫星信号质量产生影响。用户接收到异常信号后,会在一定程度上影响其位置、速度、时间(position,veloci... 详细信息

在全球卫星导航系统(global navigation satellite system,GNSS)导航信号的产生、发射、传播和接收过程中各种环节的异常,都有可能对卫星信号质量产生影响。用户接收到异常信号后,会在一定程度上影响其位置、速度、时间(position,velocity,time,PVT)性能。开展GNSS导航信号监测评估,可以在第一时间及时准确发现异常并快速告警,确保GNSS用户,特别是民航、海事等涉及生命安全领域相关用户的高效、可靠使用。然而,针对GNSS导航信号的各种异常的综合监测评估,目前国内外尚无全面而系统的研究成果,因此无法进行实时或准实时的信号异常自动识别与分析。文中提出建立GNSS导航信号畸变模型库的理念,针对GNSS导航信号的产生、发射、传播和接收过程中各类信号异常,通过仿真分析和实测数据验证,建立一套较完善的数学分析方法,研究GNSS导航信号各类常见畸变产生机理及特点,并在此基础上,定性或定量地给出不同程度的信号畸变对信号质量评估以及对用户定位的影响。本文的研究成果能够为卫星系统故障自动识别与快速定位提供支撑材料。同时,还可为卫星星上信号产生方面的设计者提供参考,在信号设计和优化过程中提供依据。

关键词：全球导航卫星系统导航信号畸变测距性能

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碳纤维表面对苯并噁嗪树脂固化动力学的影响

北京化工大学学报（自然科学版） 2005年第4期32卷 48-51页

作者：卢晓春信春玲杨小平余鼎声北京化工大学北京市新型高分子材料制备与加工重点实验室北京100029

采用非等温差示扫描量热法(DSC)研究了不同表面特征的碳纤维对苯并嗪树脂固化动力学的影响。用Kissinger方程分析计算了苯并嗪及其复合材料的固化反应表观活化能和反应级数。结果表明碳纤维表面的—OH和—COOH等弱酸性官能团对苯并... 详细信息

采用非等温差示扫描量热法(DSC)研究了不同表面特征的碳纤维对苯并嗪树脂固化动力学的影响。用Kissinger方程分析计算了苯并嗪及其复合材料的固化反应表观活化能和反应级数。结果表明碳纤维表面的—OH和—COOH等弱酸性官能团对苯并嗪的固化反应具有催化作用,同时碳纤维的加入对其固化反应具有延缓作用。碳纤维表面的环氧涂层对苯并嗪的固化反应温度、固化速率以及表观反应活化能和反应级数等也有明显的影响。

关键词：苯并噁嗪苯并噁嗪/碳纤维复合材料差示扫描量热法固化动力学

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考虑电流动态的无轴承异步电机解耦控制策略

控制理论与应用 2014年第11期31卷 1561-1567页

作者：卜文绍祖从林路春晓河南科技大学信息工程学院河南洛阳471023

目前的无轴承异步电机解耦控制策略没有考虑定子电流动态影响,限制了其控制性能的提高.为此,本文首先分析了电机的数学模型,在考虑转矩系统定子电流动态的前提下,建立了无轴承异步电机的状态方程;在系统可逆性分析的基础上,解析推导出... 详细信息

目前的无轴承异步电机解耦控制策略没有考虑定子电流动态影响,限制了其控制性能的提高.为此,本文首先分析了电机的数学模型,在考虑转矩系统定子电流动态的前提下,建立了无轴承异步电机的状态方程;在系统可逆性分析的基础上,解析推导出了无轴承异步电机的逆系统动态数学模型;基于逆系统方法,研究了转速、转子磁链和两个径向位移分量之间的动态解耦控制策略.仿真研究结果表明:控制系统具有优良的动态解耦性能和较强的抗负载挠动能力.所提出的解耦控制策略是有效的、可行的,并可在一定程度上简化控制系统结构.

关键词：异步电机无轴承转子解耦控制定子电流动态转子磁链定向控制逆系统建模

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时变路网下多配送中心多车型联合配送

科学技术与工程 2018年第36期18卷 111-119页

作者：王杨鲁晓春北京交通大学经济管理学院北京100044

随着电子商务发展,越来越多的城市、企业采用多配送中心模式,优化补货车辆、配送站点车辆出行时刻及出行路线的优化变得越来越重要。目前考虑城市时变速度特征的多车型联合配送中,对配送车辆出行时刻和配送路径联合优化角度的研究成果... 详细信息

随着电子商务发展,越来越多的城市、企业采用多配送中心模式,优化补货车辆、配送站点车辆出行时刻及出行路线的优化变得越来越重要。目前考虑城市时变速度特征的多车型联合配送中,对配送车辆出行时刻和配送路径联合优化角度的研究成果较少。基于此,主要构建基于时变速度多配送中心多车型联合配送模型;并设计基于禁忌搜索求解算法。收集了北京市城市配送大数据,以北京市公铁联运城市配送为应用背景,对算法进行了验证;通过计算发现本算法可以有效优化多配送中心多车型联合配送运输成本和时间成本,能够应用于北京这种特大城市的公铁联运城市配送方案中。

关键词：时变路网城市配送多配送中心联合配送

Recent Strategies and Advances in Hydrogel‑Based Delivery Platforms for Bone Regeneration

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Nano-Micro Letters 2025年第3期17卷 389-439页

作者： xiao Wang Jia Zeng Donglin Gan Kun Ling Mingfang He Jianshu Li Yongping lu Scientific and Technological Innovation Center for Biomedical Materials and Clinical Research Guangyuan Key Laboratory of Multifunctional Medical HydrogelGuangyuan Central HospitalGuangyuan 628000People’s Republic of China Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio‑Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023People’s Republic of China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone ***,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in *** have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological *** review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying ***,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential ***,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.

关键词： Hydrogel Bone regeneration Bioactive molecules Drug delivery Nano-/microscale carriers