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CNV-seq联合STR分型技术在早期自然流产物遗传学分析中的应用
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作者 金培芹 许阳 +1 位作者 熊英巧 彭新秀 《检验医学》 2026年第2期112-117,共6页
目的探讨基因组拷贝数变异测序(CNV-seq)和短串联重复序列(STR)分型联合检测在早期自然流产遗传学病因分析中的价值。方法选取2022年1月—2023年12月连云港市妇幼保健院自然流产患者529例。收集所有患者的流产物组织样本,采用CNV-Seq联... 目的探讨基因组拷贝数变异测序(CNV-seq)和短串联重复序列(STR)分型联合检测在早期自然流产遗传学病因分析中的价值。方法选取2022年1月—2023年12月连云港市妇幼保健院自然流产患者529例。收集所有患者的流产物组织样本,采用CNV-Seq联合STR分型检测染色体拷贝数变异(CNV)情况,对染色体非整倍体和>100 kb的CNV进行分析。对提示D、G组染色体和大片段CNV异常的流产物组织的生物学父母进行外周血G显带染色体核型分析。结果529例自然流产患者的流产物组织样本中检出322例染色体异常,其中染色体数目异常279例(染色体非整倍体异常240例、三倍体39例)、CNV异常43例(亚显微CNV 11例、大片段CNV 32例)。复发性CNV样本中有3例15q11.2微缺失综合征和2例16p11.2微缺失综合征均为家族性遗传,且父母均无明显临床表型。外周血染色体核型分析检出染色体平衡易位携带者6例、染色体罗氏易位携带者2例。结论CNV-seq联合STR分型检测可排除母源污染,检出三倍体异常,提高遗传学病因自然流产的整体检出率。对检出胚胎染色体存在D、G组非整倍体和大片段CNV异常的样本进行父母外周血染色体核型分析可以及时发现染色体平衡易位,为流产后临床管理和再生育提供指导,避免再次自然流产。 展开更多
关键词 拷贝数变异测序 短串联重复序列 核型分析 拷贝数变异 早期自然流产
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Leucine-Rich Repeat Protein Family Regulates Stress Tolerance and Development in Plants 被引量:1
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作者 HAO Zhiqi WANG Tingyi +4 位作者 CHEN Dongdong SHEN Lan ZHANG Guangheng QIAN Qian ZHU Li 《Rice science》 2025年第1期32-43,共12页
The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:tho... The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:those containing LRR domains along with other structural elements,which are further subdivided into five groups,LRR receptor-like kinases,LRR receptor-like proteins,nucleotide-binding site LRR proteins,LRR-extensin proteins,and polygalacturonase-inhibiting proteins,and those containing only LRR domains.Functionally,various LRR proteins are primarily involved in plant development and responses to environmental stress.Notably,the LRR protein family plays a central role in signal transduction pathways related to stress adaptation.In this review,we classify and analyze the functions of LRR proteins in plants.While extensive research has been conducted on the roles of LRR proteins in disease resistance signaling,these proteins also play important roles in abiotic stress responses.This review highlights recent advances in understanding how LRR proteins mediate responses to biotic and abiotic stresses.Building upon these insights,further exploration of the roles of LRR proteins in abiotic stress resistance may aid efforts to develop rice varieties with enhanced stress and disease tolerance. 展开更多
关键词 leucine-rich repeat CLASSIFICATION FUNCTION stress tolerance plant development
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混合STR图谱拆分方法及智能化趋势
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作者 毛哲华 徐珍 +3 位作者 杨帆 凃政 赵兴春 曾亮 《刑事技术》 2026年第1期57-66,共10页
在法医物证领域,解释和分析混合STR图谱因其复杂性和挑战性一直是备受关注的研究焦点,在疑难案件侦办方面有着广泛的应用。为提升混合STR图谱拆分的准确率和速度,适应复杂图谱噪声下低模板量的影响,国内外学者对混合STR图谱的拆分进行... 在法医物证领域,解释和分析混合STR图谱因其复杂性和挑战性一直是备受关注的研究焦点,在疑难案件侦办方面有着广泛的应用。为提升混合STR图谱拆分的准确率和速度,适应复杂图谱噪声下低模板量的影响,国内外学者对混合STR图谱的拆分进行了一系列研究。近几年,人工智能方法有望成为混合STR图谱拆分新的解决方案。本文综述了混合STR图谱拆分的相关研究进展,结合混合STR图谱拆分过程中的重点、难点,提出了人工智能算法在该领域潜在的应用方向,旨在为利用人工智能方法解决混合STR图谱拆分问题提供参考和思路。 展开更多
关键词 法医遗传学 DNA 混合str图谱 人工智能
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浙江汉族人群CODIS系统18个常染色体STR基因座多态性数据分析
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作者 陈德青 徐广涛 +7 位作者 金馨 孙奕欣 郑鹏宇 陈思微 马超男 陶怡宁 赵若雯 秦理想 《湖北医药学院学报》 2026年第1期52-57,65,共7页
目的:系统整理并分析近年浙江汉族人群CODIS系统18个常染色体STR基因座的文献数据,获取更精确的遗传学参数,为亲缘关系鉴定、个体识别及群体遗传学研究提供科学依据。方法:通过数据库检索相关文献,依据严格的纳入与排除标准筛选文献,最... 目的:系统整理并分析近年浙江汉族人群CODIS系统18个常染色体STR基因座的文献数据,获取更精确的遗传学参数,为亲缘关系鉴定、个体识别及群体遗传学研究提供科学依据。方法:通过数据库检索相关文献,依据严格的纳入与排除标准筛选文献,最终纳入21篇符合要求的文献进行数据提取与整合分析。结果:通过提取数据计算分析得出CODIS系统18个常染色体STR基因座的等位基因数目为11~40个、频率0.0001~0.5036;计算出纯合度(h)、杂合度(He)等6个法医学参数及对应范围;系统效能方面,累积个体识别能力为1-9.6162×10^(-21)、累积非父排除概率为1-2.2265×10^(-7),可满足个人识别和亲权鉴定需求。结论:本研究整合的数据可直接应用于司法实践中的亲缘关系鉴定和个体识别工作,同时为浙江汉族人群STR基因座的遗传学研究奠定基础。 展开更多
关键词 短串联重复序列(strs) CODIS系统 str基因座 多态性 等位基因频率
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Improvement of microstructure and microhardness of AZ31 Mg alloy sheet by cross-forging-bending repeated deformation with sharply increasing temperature
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作者 LU Li-wei LIANG Xing-jie +6 位作者 LI Min-hao WEI Yu-hui XI Yu-ze MA Min JING Lei WANG Li-fei DONG Jun 《Journal of Central South University》 2025年第11期4210-4227,共18页
In this study,AZ31 Mg alloy sheets were processed by a severe plastic deformation(SPD)technique called forging-bending repeated deformation(FBRD).The effect on the microstructure and microhardness of AZ31 Mg alloy thr... In this study,AZ31 Mg alloy sheets were processed by a severe plastic deformation(SPD)technique called forging-bending repeated deformation(FBRD).The effect on the microstructure and microhardness of AZ31 Mg alloy through FBRD was investigated with increasing temperature treatment and a 90°cross route.The results reveal that the effective strain increases with the number of passes.The flow uniformity is effectively enhanced due to alterations in shear deformation direction.After four passes of deformation,the average grain size is refined by 79.3%compared to the initial specimen.The grain refinement mechanism predominantly originates from the synergistic effects of discontinuous dynamic recrystallization(DDRX),continuous dynamic recrystallization(CDRX),and twinning-induced recrystallization(TDRX).The formation of{1012}extension twins(ET)significantly contributes to coarse grain subdivision and plastic deformation coordinated.Furthermore,pyramidal<c+a>slip activation effectively enhances the plasticity of Mg alloys.By post four-pass processing,the alloy exhibits a microhardness of 81.9HV,primarily governed by fine grain strengthening and dislocation strengthening mechanisms. 展开更多
关键词 AZ31 Mg alloy sheet forging-bending repeated deformation microstructure MICROHARDNESS
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Theoretical Modeling and Compensation of Errors in Industrial Robot Accuracy and Repeatability
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作者 Zhou Yang 《机械工程与设计(中英文版)》 2025年第2期14-17,共4页
Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechani... Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechanical wear,calibration issues,and environmental factors,can significantly impact the performance of industrial robots.This paper aims to explore the theoretical modeling of errors in industrial robot systems and propose compensation strategies to enhance their accuracy and repeatability.Key factors contributing to errors,such as kinematic,dynamic,and environmental influences,are discussed in detail.Additionally,the paper explores various compensation techniques,including geometric error compensation,dynamic compensation,and adaptive control approaches.Through the integration of error modeling and compensation methods,industrial robots can achieve improved performance,ensuring higher operational efficiency and product quality.The paper concludes by highlighting the challenges and future research directions for improving the accuracy and repeatability of industrial robots in practical applications. 展开更多
关键词 Industrial Robots ACCURACY repeatABILITY Error Modeling Compensation strategies Kinematic Errors Dynamic Errors Adaptive Control
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Complex plastome structural variation caused by intermolecular and intramolecular recombination accounts for leaf variegation in Heptapleurum ellipticum
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作者 Kainan Ma Shuaixi Zhou +1 位作者 Ying Liu Renchao Zhou 《Plant Diversity》 2026年第1期140-150,共11页
Plastome variation,including single spontaneous nucleotide substitutions and single insertions/deletions,is the major source of leaf variegation in plants.Additionally,one recent study has showed that a simple plastom... Plastome variation,including single spontaneous nucleotide substitutions and single insertions/deletions,is the major source of leaf variegation in plants.Additionally,one recent study has showed that a simple plastome structural variation,which is induced by one pair of small inverted repeats,can also result in leaf variegation.Here we show a complex plastome structural variation caused by intermolecular and intramolecular recombination across three pairs of small inverted repeats accounts for leaf variegation in a widely cultivated shrub Heptapleurum ellipticum(Araliaceae).This plastome structural variation contains two deletions and two duplications,resulting in dramatic expansion of IRs,substantial contraction of LSC and loss of 11 genes that essential for photosynthesis.Plastome heteroplasmy was detected in both green and albino sectors of variegated leaves.Relative to green sectors,albino sectors in the variegated leaves exhibit significantly reduced expression for the 11 genes lost in the mutated plastome as well as 26 other genes,but significantly increased expression for one gene related to translation apparatus.Optical and transmission electron microscopy observations showed that mesophyll cells of albino sectors possess plastids lacking grana lamellae,which likely carry the mutated plastome and contribute to albinism.In both sectors,the first layer of spongy mesophyll cells beneath the lower epidermis contains normal chloroplasts,suggesting periclinal division of the lower epidermis during development.Our study demonstrates that multiple small repeats can collectively mediate intra-and inter-molecular recombination in plastome and offers a new mechanism accounting for leaf variegation in plants. 展开更多
关键词 HETEROPLASMY Recombination PLASTOME structural variation VARIEGATION Small repeats
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The Increasing Trends of Short and Long Sleep Duration among Chinese Adults from 2010 to 2018:A Repeated Nationally Representative Cross-sectional Survey
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作者 Yun Chen Lan Wang +12 位作者 Mei Zhang Sifan Hu Yan Shao Xiao Zhang Chun Li Jie Chen Zhenping Zhao Yanhong Dong Lin Lu Maigeng Zhou Limin Wang Junliang Yuan Hongqiang Sun 《Biomedical and Environmental Sciences》 2026年第1期46-59,共14页
Objective This study aimed to determine the temporal trends in sleep duration among Chinese adults.Methods In this series of repeated nationally representative cross-sectional surveys(China Chronic Disease and Risk Fa... Objective This study aimed to determine the temporal trends in sleep duration among Chinese adults.Methods In this series of repeated nationally representative cross-sectional surveys(China Chronic Disease and Risk Factors Surveillance)conducted between 2010 and 2018,a total of 645,420 adult participants(97,741 in 2010;175,749 in 2013;187,777 in 2015;and 184,153 in 2018)were included in the trend analysis.Linear and logistic regression models were utilized to assess trends in sleep duration.Results In 2018,the estimated overall mean sleep duration among the Chinese adult population was7.58(SD,1.45)hours per day,with no significant trend from 2010.A significant increase in short sleep duration(≤6 hours)was observed in the total population,from 15.3%(95%CI:14.1%–16.5%)in 2010 to18.5%(95%CI:17.7%–19.3%)in 2018(P<0.001).Similarly,the trend in long sleep duration(>9 hours)was also significant,increasing in weighted prevalence from 7.2%(95%CI:6.3%–8.1%)in 2010 to 9.0%(95%CI:8.2%–9.9%)in 2018(P<0.001).Conclusion The prevalence of both short and long sleep durations significantly increased among Chinese adults from 2010 to 2018,highlighting the urgency of health initiatives to promote optimal sleep duration in China. 展开更多
关键词 Sleep duration Trend analysis repeated cross-sectional study Nationally representative survey CCDRFS
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Utility of liver surface-guided encirclement of hepatoduodenal ligament for the Pringle maneuver in minimally invasive repeat liver resection
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作者 Yoichi Kawano Takahiro Murokawa +18 位作者 Yuto Aoki Akira Hamaguchi Takashi Ono Takahiro Haruna DaigoYoshimori Toshiyuki Irie Junji Ueda Tetsuya Shimizu Akira Matsushita Mampei Kawashima Ryo Ga Hiroyasu Furuki Tomohiro Kanda Yukio Oshiro Keisuke Minamimura Masato Yoshioka Nobuhiko Taniai Yoshiharu Nakamura Hiroshi Yoshida 《World Journal of Gastroenterology》 2026年第1期126-138,共13页
BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly dev... BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly developed Pringle taping method guided by liver surface in MISRLR.METHODS We retrospectively reviewed 72 cases of MISRLR performed by a single surgeon at two centers from August 2015 to July 2024.Beginning in October 2019,a liver surface-guided encirclement of hepatoduodenal ligament(LSEH)was used for repeat Pringle taping.Perioperative outcomes including Pringle taping success,operative time,blood loss,conversion rate,morbidity,and mortality were assessed.RESULTS Laparoscopic and robotic approaches were used in 63 patients and 9 patients,respectively.The median operative time,blood loss,and hospital stay were 331.5 minutes,70 mL,and 8 days,respectively.Open conversion occurred in two cases(2.8%)due to severe adhesions and right renal vein injury.Clavien-Dindo grade≥III complications occurred in 5.6%of cases with no mortality.Anti-adhesion barriers were used in 54 patients(75.0%).LSEH was attempted in 57 cases,improving Pringle taping success from 33.0%to 91.4%(P<0.001).LSEH succeeded in all patients with prior open liver resection(n=11).Among 6 patients in whom LSEH failed,3 patients(50.0%)had undergone a third liver resection,and 1 patient had a history of distal gastrectomy with choledochoduodenostomy.CONCLUSION The newly developed LSEH technique for Pringle taping in MISRLR was feasible,enhancing safety and reproducibility even in patients with a history of open liver resection. 展开更多
关键词 Laparoscopic liver resection repeat liver resection Pringle maneuver Postoperative adhesion Minimally invasive liver resection Hepatocellular carcinoma Cancer of colon and rectum Liver metastasis Guidelines Second and third hepatectomies
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10%非缓冲福尔马林固定时间对人体骨骼STR检测的影响
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作者 高林林 洪亮 +3 位作者 周志全 蔡鸿勇 张明亚 汪旭峰 《刑事技术》 2025年第4期393-398,共6页
为了评价10%非缓冲福尔马林固定时间对人体骨骼STR检测的影响,本文选取了5根长骨,用电锯将骨干段分成12段,采用10%非缓冲福尔马林在常温浸泡固定,不同时间段取样,提取的DNA通过QuantiFiler?Trio DNA Quantifcation Kit进行定量,使用IDen... 为了评价10%非缓冲福尔马林固定时间对人体骨骼STR检测的影响,本文选取了5根长骨,用电锯将骨干段分成12段,采用10%非缓冲福尔马林在常温浸泡固定,不同时间段取样,提取的DNA通过QuantiFiler?Trio DNA Quantifcation Kit进行定量,使用IDentifer DNA(炎黄34)和SureID?X37试剂盒进行PCR扩增,最后经3500xL基因分析仪电泳获得样本STR分型数据。研究发现骨骼固定时间与DNA质量浓度成反比,与DNA降解指数成正比。在非缓冲福尔马林中固定10 d以内的骨骼,常染色体及X染色体检验均可以获得完整STR分型。固定时间在22 d以内的样本,STR的检出率可保持在77.33%以上。当固定时间延长至30 d后,样本的等位基因检出率大幅度下降至30%左右。当固定时间达到60 d后,所有样本的DNA定量结果降至0.02 ng/μL以下,只有部分样本检测到零星的小片段STR分型结果。综上,10%非缓冲福尔马林固定时间影响着骨骼所提取到的DNA,从而影响了人体骨骼STR的检出率。 展开更多
关键词 法医物证学 10%非缓冲福尔马林 固定时间 人体骨骼 短串联重复序列(str)
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江苏地区汉族人群6812例亲子鉴定案例中39个STR基因座突变特征分析
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作者 叶琴 居晓斌 +2 位作者 吴蕾 陈群 徐婷 《南京医科大学学报(自然科学版)》 北大核心 2025年第9期1293-1300,共8页
目的:分析江苏省汉族人群亲子鉴定中39个短串联重复序列(short tandem repeat,STR)基因座的突变特征。方法:选取2019年1月—2024年12月南京医科大学第一附属医院司法鉴定所受理的6812例亲子鉴定案例,采用GoldenEye^(TM) DNA身份鉴定系... 目的:分析江苏省汉族人群亲子鉴定中39个短串联重复序列(short tandem repeat,STR)基因座的突变特征。方法:选取2019年1月—2024年12月南京医科大学第一附属医院司法鉴定所受理的6812例亲子鉴定案例,采用GoldenEye^(TM) DNA身份鉴定系统检测39个STR基因座的突变情况,对突变率、突变来源和步数进行统计分析。结果:在6812例认定亲子关系的案例中,三联体1680例,二联体5132例。共发现214例突变案例,总突变率2.52%。其中,D12S391基因座突变率最高,达0.3297%(28/8492),其次为Penta E、FGA、D21S11、D18S51、D3S1358基因座,突变率均在0.20%以上。突变来源分析中,父源突变189例,母源突变20例,不明原因突变5例,父源突变显著高于母源(P<0.001)。203例(94.86%)突变为一步突变,二步突变9例,FGA和D21S11基因座三步突变各1例。结论:亲子鉴定中39个STR基因座总突变率较高,达2.52%,具有性别和地区差异,在亲子鉴定实践中需加以重视,该结果为江苏地区汉族人群STR基因座突变情况提供数据支撑,有助于提升复杂亲缘关系鉴定的准确性。 展开更多
关键词 亲子鉴定 短串联重复序列 基因突变 法医遗传学
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法医生物降解检材 快速高效DNA检测方法——15Mini-STR复合扩增体系构建
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作者 冯涛 龙兵 +4 位作者 彭清晨 程昱 高天珍 龙杰 李玥 《警察技术》 2025年第6期49-53,共5页
对25A-CSTR试剂盒300bp以上基因座重新设计引物,研究建立包含13个常染色体STR基因座、1个Y-indel以及1个性别基因座Amel的Mini-STR复合扩增体系,新建体系可与25A-CSTR试剂盒采用相同的扩增参数和电泳程序对提取产物进行检验,提升法医生... 对25A-CSTR试剂盒300bp以上基因座重新设计引物,研究建立包含13个常染色体STR基因座、1个Y-indel以及1个性别基因座Amel的Mini-STR复合扩增体系,新建体系可与25A-CSTR试剂盒采用相同的扩增参数和电泳程序对提取产物进行检验,提升法医生物降解检材检出效率。选择D21S11、Penta E、D19S433、D16S539、PentaD、D2S1138、D18S51、D22S1045、TPOX、FGA、D10S1248、D6S1043、D7S820、1个Y-indel以及1个性别基因座Amel,重新设计引物,优化反应体系并验证。结果表明,15Mini复合扩增体系通过验证性能稳定可靠,与25A-C STR试剂盒联用性强,灵敏度高,适合实际办案的需要。 展开更多
关键词 短串联重复序列 降解检材检测 str复合扩增
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The Construction of Active Source Repeated Monitoring in the Qilian Mountain, Gansu Province 被引量:4
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作者 Zhang Yuansheng Guo Xiao +11 位作者 Qin Manzhong Liu Xuzhou Wei Congxin Shen Xuzhang Yan Wenhua Zou Rui Yin Liang Wang Yahong Sun Dianfeng Feng Hongwu Zhang Lifeng Guo Yingxia 《Earthquake Research in China》 CSCD 2016年第3期333-341,共9页
The exciting source of the active source repeated monitoring is located in the Xiliushui Reservoir in Zhangye,Gansu Province. The system began operating normally on July 9,2015,and we had completed a period of 40 days... The exciting source of the active source repeated monitoring is located in the Xiliushui Reservoir in Zhangye,Gansu Province. The system began operating normally on July 9,2015,and we had completed a period of 40 days of continuous excitation experiment before November 10,2015. Our results reveal that the airgun source has good consistency and repeatability,and the detective system of active source can record signal clearly. The construction of active source repeated exploration projects has achieved some results,which can provide valuable experience for the research of active source repeated exploration. The observation data we obtained makes it possible to follow the temporal and spatial variations of the deep structure of the Qilian Mountain areas. 展开更多
关键词 Active source repeated monitoring Qilian Mountain Gansu Province
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Strength and Chloride Diffusion Behaviour of Three Generations of Repeated Recycled Fine Aggregate Concrete 被引量:2
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作者 ZHU Pinghua LIU Wenying +2 位作者 NIU Zhigang WEI Da HU Kun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第5期1113-1120,共8页
The feasibility of using different generations of recycled fine aggregate(RFA) in structural concrete in a chloride environment was evaluated by studying the performance of the RFA and the corresponding concrete. Th... The feasibility of using different generations of recycled fine aggregate(RFA) in structural concrete in a chloride environment was evaluated by studying the performance of the RFA and the corresponding concrete. The different generations of RFA were recycled by following the cycle of ‘concrete-waste concrete-fine aggregate-concrete'. The properties of three generations of repeatedly recycled fine aggregate(RRFA) were systematically investigated, and we focused on the compressive strength and splitting tensile strength and chloride ion permeability of the related structural concretes with 25%, 75%, and 100% replacement of natural fine aggregates with RFA. The results indicated that the quality of RRFA presents a trend of slow deterioration, but the overall performance of all RRFA still fulfils the quality requirements of recycled fine aggregate for structural concrete. All RRFA concretes achieved the target compressive strength of 40 MPa after 28 days except for the second generation of the recycled aggregate concrete and the third generation of the recycled aggregate concrete with 100% replacement, and all the concrete mixes achieved the target compressive strength after 90 days. The insights obtained in this study demonstrate the feasibility of using at least three generations of RRFA for the production of normal structural concrete with a design service life of 100 years in a chloride environment. 展开更多
关键词 repeated recycled concrete repeatedly recycled fine aggregate compressive strength chloride ion diffusion
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Structure and properties of AZ31B magnesium alloy sheets processed by repeatedly unidirectional bending at different temperatures 被引量:8
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作者 黄光胜 宋波 +1 位作者 徐伟 张雷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1815-1821,共7页
Repeatedly unidirectional bending(RUB) was applied to the magnesium alloy sheet to improve the basal texture.The effect of RUB temperature on resulting structure and room temperature properties was investigated.The te... Repeatedly unidirectional bending(RUB) was applied to the magnesium alloy sheet to improve the basal texture.The effect of RUB temperature on resulting structure and room temperature properties was investigated.The texture components of the sheet undergoing RUB at recovery temperature were similar to those of the sheet undergoing RUB at room temperature(RT).As the RUB temperature increased to above recrystallization temperature,the texture components became more disperse and the pyramidal components increased.With the increase of RUB temperature,the grain size near the surface of the sheets undergoing RUB tended to grow up.When the sheets were processed by RUB at medium-high temperature followed by annealing at 533 K,the yield strength and fracture elongation were lower than those of the cold rolled sheet;however,the Erichsen value was slightly higher than that of the cold rolled sheet.The sheet undergoing RUB at RT followed by annealing at 533 K represented the best mechanical properties. 展开更多
关键词 magnesium alloy sheets repeatedly unidirectional bending deformation temperature TEXTURE
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Effect of Deformation Temperatures on Microstructure of AQ80 Magnesium Alloy under Repeated Upsetting-Extrusion 被引量:5
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作者 Yutian Fan Liwei Lu +3 位作者 Hongliang Zhao Zhiqiang Wu Yong Xue Wen Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2023年第10期1649-1664,共16页
A new repeated upsetting-extrusion (RUE) process was proposed to improve the microstructure and the mechanical properties of Mg alloys. The effects of deformation temperature on the microstructure and microhardness of... A new repeated upsetting-extrusion (RUE) process was proposed to improve the microstructure and the mechanical properties of Mg alloys. The effects of deformation temperature on the microstructure and microhardness of RUEed AQ80 Mg alloy were studied. The results showed that Mg alloy is subjected to sufficient corner shear deformation, upsetting deformation, and extrusion deformation, resulting in a large and uniformly distributed effective strain after RUE deformation. The microstructure is refined to an average grain size of 2.1 μm by the continuous dynamic recrystallization (CDRX) mechanism at 250 °C. As the temperature increases to 300 °C, the discontinuous dynamic recrystallization (DDRX) mechanism is activated and the average grain size is refined to 1.6 µm by the combined effect of CDRX and DDRX. In comparison to their parent grains, the orientations of the CDRXed grains show a clearly preferred orientation, but those of the DDRXed grains are completely different. At 350 °C, {10-12} extension twins appear in the microstructure, and the twinning-induced recrystallization (TDRX) mechanism plays an important role in grain refinement. With the two strengthening mechanisms of fine-grained strengthening and dislocation strengthening, the microhardness of the 250 °C sample is greatly improved, with an increase of about 35.1% compared to the initial sample. 展开更多
关键词 AQ80 Mg alloy repeated upsetting-extrusion MICROstrUCTURE MICROHARDNESS
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Evaluation of Population Structure, Genetic Diversity and Origin of Northeast Asia Weedy Rice Based on Simple Sequence Repeat Markers 被引量:1
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作者 LI Mao-bai WANG Hui CAO Li-ming 《Rice science》 SCIE CSCD 2015年第4期180-188,共9页
Weedy rice exerts a severe impact on rice production by competing for sunlight, water and nutrients. This study assayed the population structure, genetic diversity and origin of Northeast Asia weedy rice by using 48 s... Weedy rice exerts a severe impact on rice production by competing for sunlight, water and nutrients. This study assayed the population structure, genetic diversity and origin of Northeast Asia weedy rice by using 48 simple sequence repeat markers. The results showed that weedy rice in Northeast Asia had a high genetic diversity, with Shannon's diversity index (I) of 0.748 and the heterozygosity (He) of 0.434. In each regional population, I value varied widely. The widest range of I (0.228-0.489) was observed in the weedy rice of Eastern China, which was larger than that of Northeast China and Korea (0.168-0.270). The F-statistics of regional populations (Fis, Fit and Fst) also showed higher values in the weedy rice of Eastern China than those of Northeast China and Korea All weedy rice accessions were grouped into two clusters in the unweighted pair group method with arithmetic mean cluster analysis dendrogram, namely Eastern China branch and Northeastern China plus Korea branch. There was significant differentiation in genetic characteristics in weedy rice of northeastern and eastern Asia, especially in Eastern China. 展开更多
关键词 weedy rice simple sequence repeat genetic diversity population structure weed control
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Screening for simple sequence repeat markers in Puccinia striiformis tritici based on genomic sequence 被引量:2
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作者 Gang-ming ZHAN Fu-ping WANG +4 位作者 Huai-yong LUO Shu-chang JIANG Wen-ming ZHENG Li-li HUANG Zhen-sheng KANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2015年第8期727-732,共6页
Puccinia striiformis f. sp. tritici (Pst) is the obligate biotrophic fungus responsible for stripe rust wheat. In this study, we developed and characterized 20 polymorphic microsatelUte markers from the genomic sequ... Puccinia striiformis f. sp. tritici (Pst) is the obligate biotrophic fungus responsible for stripe rust wheat. In this study, we developed and characterized 20 polymorphic microsatelUte markers from the genomic sequence of an isolate of Chinese Pst race C^32. Polymorphism at each simple sequence repeat (SSR) locus was determined using 32 Pst isolates from 7 countries. The number of alleles varied from 2 to 7 across isolates, and the observed and expected heterozygosities ranged from 0.33 to 0.97 (mean 0.62) and 0.23 to 0.73 (mean 0.51 ), respectively. As expected the genomic SSR markers were more polymorphic than the expressed sequence tag (EST)-SSR markers developed previously. These markers will be more useful for population genetics and molecular genetics studies in Pst. 展开更多
关键词 Microsatellites Simple sequence repeat stripe rust
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Relevance of MUC1 mucin variable number of tandem repeats polymorphism in H pylori adhesion to gastric epithelial cells 被引量:4
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作者 Natália R Costa Nuno Mendes +4 位作者 Nuno T Marcos Celso A Reis Thomas Caffrey Michael A Hollingsworth Filipe Santos-Silva 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第9期1411-1414,共4页
AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were per... AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (GP202 and MKN45) and GP202 clones expressing recombinant MUC1 with different VNTR lengths. RESULTS: Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P < 0.05) adhesion to all the cell lines and clones tested, when compared to the non-pathogenic strain HPTx30a. Bacteria showed a significantly higher (P < 0.05) adhesion to the GP202 cell line, when compared to the MKN45 cell line. Furthermore, both strains showed a significantly higher (P < 0.05) adhesion to GP202 clones with larger MUC1 VNTR domains. CONCLUSION: This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells. The extent of bacterial adhesion depends on the size of theMUC1 VNTR domain. The adhesion is further dependent on bacterial pathogenicity and the gastric cell line. MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa. 展开更多
关键词 HPYLORI MUC1 Variable number of tandem repeats POLYMORPHISM ADHESION MUCIN GAstrIC Infection
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Repeated Strike Process During Disconnector Operation in Ultra-High Voltage Gas-Insulated Switchgear 被引量:1
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作者 关永刚 蔡元纪 +4 位作者 陈维江 刘卫东 李志兵 岳功昌 张俊民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第3期247-253,共7页
Very fast transient over-voltage (VFTO), induced by disconnector operations in gas- insulated switchgears, has become the limiting dielectric stress at ultra-high voltage levels. Much work has been done to investiga... Very fast transient over-voltage (VFTO), induced by disconnector operations in gas- insulated switchgears, has become the limiting dielectric stress at ultra-high voltage levels. Much work has been done to investigate single-strike waveforms of VFTO. However, little study has been carried out investigating the repeated strike process, which would influence VFTO significantly. In this paper, we carried out 450 effective experiments in an ultra-high voltage test circuit, and conducted calculations through the Monte Carlo simulation method, to investigate the repeated strike process. Firstly, the mechanism of the repeated strike process is proposed, based on the ex- perimentai results. Afterwards, statistical breakdown characteristics of disconnectors are obtained and analyzed. Finally, simulations of the repeated strike process are conducted, which indicate that the dielectric strength recovery speed and polarity effect factor have a joint effect on VFTO. This study enhances the understanding of the nature of VFTO, and may help to optimize the disconnector designed to minimize VFTO. 展开更多
关键词 disconnector (DS) repeated strike process DISCHARGE statistical breakdowncharacteristics ultra-high voltage (UHV) very fast transient over-voltage (VFTO)
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