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Expansin Genes Expressed Differentially in Peduncle Elongation of Near-Isogenic Wheat Rht Lines

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Journal of Integrative Agriculture 2014年第10期13卷 2091-2101页

作者： WANG Jia-li LIU Dong-cheng GUO Xiao-li YANG Wen-long zhang ai-min State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences Institute of Shandong River Wetlands College of Biology China Agricultural University The Collaborative Innovation Center for Grain Crops in Henan College of AgronomyHenan Agricultural University

The introduction of reduced height （Rht） genes Rht-Blb and Rht-Dlb led to impressive increases in wheat （Triticum aestivum L.） yields during the Green Revolution. In the present study, the dynamic elongation of peduncle in a set ofnear-isogenic lines （NILs） carrying different Rht alleles （Rht-Blb, Rht-Dlb, Rht-Blc, Rht-Dlb＋Rht-Blb, and Rht-Dlb＋Rht-Blc） were investigated. The reduction of the final length of peduncle in NILs was dependent mainly on the elongation rate, which was reduced by Rht genes, during rapid elongation phase. Resin sections showed that Rht genes strongly reduced the cell extension in peduncle. The expression of expansin genes, which mediate cell wall loosening and leading to cell expansion, were analysed by using real- time quantitative PCR （qPCR）. Among the 23 possible wheat expansin genes, 17 were expressed in the peduncle. The spatial distribution of expression was further analysed for five expansins that showed high expression levels in the peduncles of Rht lines. Compared to wild type plants, the incorporation of Rht-Dlb allele decreased about 37 and 80% of the expression levels of ExpA 7 and ExpA3 in elongation zone, respectively. The presence Rht-Blc dwarfing genes, however, produced 53% reduction in the expression level of ExpA7, and seriously decreased about 70% of ExpB9 expression. Although the expression levels of five genes exhibited variability among the lines, an expansin gene, ExpB2, showed its expression level highly associated with the cell elongation rate in peduncle of different Rht lines.

关键词： expansin peduncle gene expression dwarfing gene

2020—2022年天津市南开医院临床常见胆道感染的病原学特征及危险因素分析

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中国中西医结合外科杂志 2024年第2期30卷 248-253页

作者：陈明慧张爱民薛海玲房杰贾晓冬天津市南开医院医学检验科天津300100 天津金域医学检验实验室有限公司天津300100

目的:分析天津市南开医院临床常见的胆道感染病原学特征及危险因素,为胆道感染的临床治疗用药提供依据。方法:选取2020年1月—2022年12月天津市南开医院收治的672例胆道疾病患者作为研究对象,根据是否发生胆道感染(BTI)将患者分为BTI组(... 详细信息

目的:分析天津市南开医院临床常见的胆道感染病原学特征及危险因素,为胆道感染的临床治疗用药提供依据。方法:选取2020年1月—2022年12月天津市南开医院收治的672例胆道疾病患者作为研究对象,根据是否发生胆道感染(BTI)将患者分为BTI组(n=361)和非BTI组(n=311);采集患者的年龄、性别、基础疾病情况、胆结石数量、抗菌药物使用情况和病原学检查结果等资料,分析胆石症患者并发BTI的危险因素与病原学特征。结果:胆汁培养共分离病原菌3534株,其中革兰阴性菌2375株,占67.20%;革兰阳性菌1058株,占29.94%;真菌92株,占2.60%。大肠埃希菌对环丙沙星的耐药率呈上升趋势(P65岁、有胆道手术史、结石数目>2个是胆石症患者并发BTI的独立危险因素(P<0.05)。结论:临床胆道感染分离的病原菌以革兰阴性杆菌最常见,耐药性不断变迁,应根据药敏结果合理用药;患者发生胆道感染与年龄、胆道手术史和胆结石数目有相关性,临床应增强感染防护。

关键词：胆道感染病原菌耐药性

The Combined Effects of Electromagnetic Stirring and Al-5C Master Alloy on Grain Refinement of AZ31 Magnesium Alloy

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Journal of Iron and Steel Research International 2012年第S1期19卷 222-225页

作者： zhang ai-min HAO Hai LI ming zhang Xing-guo School of Materials Science and Engineering Dalian University of Technology

Al-5wt.%C(similarly hereinafter)master alloy as a refiner has been developed by powder in situ synthesis process,and the combined effects of Al-5C refiner and EMS(electromagnetic stirring)on grain refinement of AZ31 alloy are *** results indicate that the A1-5C refiner and EMS can remarkably reduce the grain size of AZ31 alloy. The average grain size of AZ31 alloy decreased firstly and then increased with the increasing addition amount of the Al-5C master alloy,and the optimum addition amounts is 2wt.%.While the AZ31 alloy with 3wt.%Al-5C master alloy solidified under EMS,the average grain size further reduced and is less than that treated only by *** refining mechanism of AZ31 alloy refined by Al-5C master is owing to the polygonal Al_8(Mn,Fe)_5 particles acting as nucleating substrates for α-Mg *** more distribution of Al_8(Mn,Fe)_5 and Al4C3 particles generated by EMS contribute to the further refinement when treated by combining with Al-5C refiner.

关键词： AZ31 magnesium alloy grain refinement Al-5C refiner EMS

脾瘅方加减联合二甲双胍治疗肥胖型2型糖尿病的临床疗效及对其血脂、胰岛素抵抗指数的影响

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世界中西医结合杂志 2024年第3期19卷 591-595页

作者：张爱民赵燕燕胡磊磊曹艳华济宁市中医院内分泌科山东济宁272000

目的分析脾瘅方加减联合二甲双胍治疗肥胖型2型糖尿病(Diabetes mellitus type 2,T2DM)患者的临床疗效及对其血脂、胰岛素抵抗指数(Homeostatic Model Assessment of Insulin Resistance,HOMA-IR)的影响。方法选取2022年1月—2023年2月期间就诊于济宁市中医院的肥胖型T2DM患者100例作为研究对象,按随机数表法分为对照组和观察组,每组各50例。对照组常规服用二甲双胍0.5 g/次,3次/d;观察组在对照组基础上加用脾瘅方对症加减治疗。治疗12周后观察比较两组患者临床疗效,治疗前后血糖指标[血糖(Fasting blood glucose,FBG)、餐后2 h血糖(2-hour postprandial blood glucose,2 h PBG)、糖化血红蛋(Glycosylated hemoglobinA1c,HbA1c)]、中医证候积分、血脂指标[总胆固醇(Total cholesterol,TC)、甘油三酯(Triglycerides,TG)、低密度脂蛋白(Low density lipoprotein,LDL-C)]、胰岛素指标[空腹胰岛素(Fasting insulin,FINS)、胰岛素抵抗指数(Homeostasis Model Assessment-Insulin Resistance,HOMA-IR)、胰岛β细胞功能指数(Homeostatic model assessment ofβ-cell function,HOMA-β)]及炎症因子[白介素-6(Interleukin-6,IL-6)、超敏C反应蛋白(Highsensitivity C-reactive protein,hs-CRP)]水平。结果治疗后观察组临床总有效率94.00%(47/50)明显高于对照组78.00%(39/50),差异有统计学意义(P<0.05)。治疗后两组患者血糖FBG、2 h PBG、HbAlc指标及中医证候积分均较治疗前降低,差异有统计学意义(P<0.05);且观察组血糖FBG、2 h PBG、HbAlc指标及中医证候积分均明显低于对照组,差异有统计学意义(P<0.05)。治疗后两组患者血脂指标TG、TC、LDL-C均较治疗前降低,差异有统计学意义(P<0.05);且观察组血脂指标TG、TC、LDL-C均明显低于对照组,差异有统计学意义(P<0.05)。治疗后两组患者胰岛素FINS、HOMA-IR指标均较治疗前降低,HOMA-β指标均较治疗前升高,差异有统计学意义(P<0.05);且观察组胰岛素FINS、HOMA-IR指标明显低于对照组,HOMA-β指标明显高于对照组,差异有统计学意义(P<0.05)。治疗后两组患者炎症因子IL-6、hs-CRP水平均较治疗前降低,差异有统计学意义(P<0.05);且观察组炎症因子IL-6、hs-CRP水平均明显低于对照组,差异有统计学意义(P<0.05)。结论脾瘅方加减联合二甲双胍治疗肥胖型T2DM患者能有效调节血糖、血脂水平,改善胰岛素抵抗,减轻炎症反应,临床疗效显著。

关键词：脾瘅方二甲双胍肥胖型2型糖尿病血脂胰岛素抵抗指数

Wear behavior of copper material removal during fluid jet polishing:A comparative study between experiment and simulation

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Friction 2024年第8期12卷 1680-1695页

作者： Wenjing zhang Xin zhang Tiancheng ai Dan GUO Guoshun PAN State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Guangdong Provincial Key Laboratory of Optomechatronics Shenzhen 518057China

As a crucial part in micro-electromechanical manufacture,local ultra-precision processing of highly ductile copper is expected to be realized by fluid jet polishing(FJP),which widely utilized in optical *** copper exhibits different wear behavior from stiff and brittle material,there is currently no abrasive wear prediction model applicable for copper to investigate the polishing *** research reveals that the copper material removal is dominated by deformation wear rather than cutting wear through abrasive jet impact experiments and localized wear scars analysis.A three-dimensional gas-liquid-particle triphasic wear model for copper in FJP is developed by considering impact energy and wear mechanism ***,validation assessments at various working pressures and impingement angles achieve the goodness-of-fit up to 0.92–0.97 in quantitative comparison between simulations and experimental measurements,which demonstrate the wear prediction ability of the proposed *** investigation facilitates a better understanding of copper wear mechanism and provides theoretical guidance for FJP process optimization.

关键词： fluid jet polishing(FJP) wear mechanism computational fluid mechanics wear model material removal

Reliability ensemble averaging reduces surface wind speed projection uncertainties in the 21st century over China

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Advances in Climate Change Research 2024年第2期15卷 222-229页

作者： Zheng-Tai zhang Chang-ai XU Key Laboratory for Semi-Arid Climate Change of the ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

Accurate prediction of future surface wind speed(SWS)changes is the basis of scientific planning for wind *** studies have projected SWS changes in the 21st century over China on the basis of the multi-model ensemble(MME)of the 6th Coupled Model Intercomparison Project(CMIP6).However,the simulation capability for SWS varies greatly in CMIP6 multi-models,so the MME results still have large *** this study,we used the reliability ensemble averaging(REA)method to assign each model different weights according to their performances in simulating historical SWS changes and project the SWS under different shared socioeconomic pathways(SSPs)in *** results indicate that REA considerably improves the SWS simulation capacity of CMIP6,eliminating the overestimation of SWS by the MME and increasing the simulation capacity of spatial *** spatial correlations with observations increased from 0.56 for the MME to 0.85 for ***,REA could eliminate the overestimation of the SWS by 33%in *** for southeastern China,the SWS generally decreases over China in the near term(2020-2049)and later term(2070-2099),particularly under high-emission *** SWS reduction projected by REA is twice as high as that by the MME in the near term,reaching-4%to-3%.REA predicts a larger area of increased SWS in the later term,which expands from southeastern China to eastern *** study helps to reduce the projected SWS uncertainties.

关键词： Surface wind speed Uncertainty Multi-model ensemble Reliability ensemble averaging CMIP6

Effects of Ultrasonic Vibration and Electromagnetic Stirring on the Dispersion of TiB_2 Particles for AZ31 Magnesium Alloy

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Journal of Iron and Steel Research International 2012年第S1期19卷 359-362页

作者： FANG Can-feng WANG Lao-hu MENG Ling-gang HAO Hai zhang ai-min zhang Xing-guo School of Materials Science and Engineering.Dalian University of Technology

In-situ TiB_2/AZ31 composites were prepared by utilizing the SHS reaction of Al-Ti-B system in the molten magnesium,and the effects of external physical fields on the dispersion of TiB_2 particles were *** results show that high-energy ultrasonic vibration could effectively break up the particle clusters and make the TiB2 particles uniformly distributed in the melt of TiB_2/AZ31 *** compound field(high-energy ultrasonic field coupling with electromagnetic field)could not only distribute the TiB_2 particles into the matrix uniformly,but also make the grains of α-Mg free and uniform further than the ultrasonic field *** average grain size of as-cast TiB_2/AZ31 composites was reduced from 173μm to 94μm.

关键词： TiB_2/AZ31 magnesium matrix composites ultrasonic vibration electromagnetic field compound field

Improvement on Mixograph test through water addition and parameter conversions

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Journal of Integrative Agriculture 2015年第9期14卷 1715-1722页

作者： SUN Jia-zhu YANG Wen-long LIU Dong-cheng ZHAO Jun-tao LUO Guang-bin LI Xin LIU Yan-jun GU O Jin-kao zhang ai-min State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences Zhaoxian Institute of Agricultural Sciences Shijiazhuang Academy of Agriculture and Forestry Sciences

To improve Mixograph testing effect, Farinograph measurements were adopted as a quality standard and changes in water absorption and parameter conversion in Mixograph test were explored. Comparative study showed that increasing water absorption to about 73% and converting original parameters to compound parameters in Mixograph tests signiifcantly increased their predictive power for lfour quality. These efforts also enabled the adoption of ifxed water addition level in Mixograph test and simpliifed the test procedure signiifcantly. With the success in parameter conversions, Mixograph test results were successful y described by Farinograph parameters, which al ow breeders to compare and exchange test results easily. Al these changes optimized the ofifcial method of Mixograph test with simpliifed procedure and enhanced reliability and made the Mixograph being the superior tool for quality assessment in wheat-breeding programs.

关键词： Mixograph water absorption compound parameter constant water addition parameter conversion

Pricing Guaranteed minimum Death Benefits with Dollar Cost Averaging Under Time-changed Le′vy Models

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Acta Mathematicae Applicatae Sinica 2024年

作者： Jia-ming WANG Mei-qiao ai Zhi-min zhang College of Mathematics and Statistics Chongqing University

In this paper, we propose an efficient and accurate method for pricing Guaranteed minimum Death Benefit (GMDB) under time-changed Le′vy processes. Suppose that the GMDB payoff depends on a dollar cost averaging (DCA) style periodic investment, and the activity rate process in stochastic time change is modeled by a square-root process. We develop a recursive method to derive the closed form valuation formula by using the frame duality projection method. Numerical examples are reported for demonstrating the effectiveness of our approach and illustrating the interplay between contract parameters and the valuation.

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