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Winter wheat yield improvement by genetic gain across different provinces in China

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Journal of Integrative Agriculture 2024年第2期23卷 468-483页

作者： wei Chen jingjuan Zhang Xiping Deng Key Laboratory of Disaster Monitoring and Mechanism Simulating of Shaanxi Province/School of Geography and Environment Baoji University of Arts and SciencesBaoji 721013China Centre for Crop and Food Innovation Murdoch University90 South StreetMurdochWA 6150Australia State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China

The replacement of winter wheat varieties has contributed significantly to yield improvement worldwide,with remarkable progress in *** on two sets of data,production yield from the National Bureau of Statistics of China and experimental yield from literature,this study aims to(1)illustrate the increasing patterns of production yield among different provinces from 1978 to 2018 in China,(2)explore the genetic gain in yield and yield relevant traits through the variety replacement based on experimental yield from 1937 to 2016 in China,and(3)compare the yield gap between experimental yield and production *** results show that both the production and experimental yields significantly increased along with the variety *** national annual yield increase ratio for the production yield was 1.67%from 1978 to 2018,varying from 0.96%in Sichuan Province to 2.78%in Hebei Province;such ratio for the experimental yield was 1.13%from 1937 to *** yield gap between experimental and production yields decreased from the 1970s to the *** study reveals significant increases in some yield components consequent to variety replacement,including thousand-grain weight,kernel number per spike,and grain number per square meter;however,no change is shown in spike number per square *** biomass and harvest index consistently and significantly increased,whereas the plant height decreased significantly.

关键词： genetic gain winter wheat yield yield components

A new thinprep cytologic test of cervical cells and its application

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Frontiers of Medicine 2009年第2期3卷 227-229页

作者： Xiaojun ZHAO jingjuan wei Rong WANG Yajun GU Yunde LIU Clinical Laboratory Science Department of Tianjin Medical University Tianjin 300203China

In order to improve the quality of routine cervical smears,we investigated the new Thinprep cytologic test(TCT)for cervical *** this study,100 women who were enrolled were randomly divided into two *** one group,the TCT for cervical cells was applied(TCT group),and in the other group routine cervical smear was *** addition,the cells in the TCT group were screened by double sifters,and centrifuged using a separation medium so as to eliminate mucus,inﬂammatory cells and blood *** to the cell distribution and the thickness of the smear,the results were assigned to three groups,including satisfactory smears,less satisfactory smears and unsatisfactory *** TCT had a higher satisfactory rate(98%)compared to the routine cervical smear(32%)(P<0.01),indicating the TCT was superior to the routine cervical *** is concluded that the TCT is more ***,in comparison to the routine cervical smear,the TCT for cervical cells has 5 advantages which can greatly increase the cytological accuracy.

关键词： thinprep cytologic test cervical cells Papani-colaou smear

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高铁区位对中国异地投资的影响与异质性评价

地理科学 2024年第3期44卷 400-410页

作者：焦敬娟马王钰青王伟北京交通大学经济管理学院北京100044 中国铁路经济规划研究院有限公司经济与管理研究所北京100038 青岛大学旅游与地理科学学院山东青岛266071

作为一种特殊的跨区域重大基础设施,高速铁路(下文简称为“高铁”)开通减少沿线企业面临的要素约束,降低企业间的信息不对称和代理成本,促进沿线地区资本流动,影响城市间的异地投资。依托2008-2017年中国上市公司新建投资决策数据,以高... 详细信息

作为一种特殊的跨区域重大基础设施,高速铁路(下文简称为“高铁”)开通减少沿线企业面临的要素约束,降低企业间的信息不对称和代理成本,促进沿线地区资本流动,影响城市间的异地投资。依托2008-2017年中国上市公司新建投资决策数据,以高铁所引致的连通性和可达性等区位条件变化为切入,分析和评价高铁对异地投资的影响及其空间异质性。研究发现:①东部地区连通性提升更快,西部地区可达性改善更显著;巨特大城市与中小城市的可达性和连通性的绝对差距不断拉大。②异地投资主要流向东部地区和巨特大城市,但地区差异呈缩小态势。③高铁区位对异地投资有显著正向影响,并且可达性的影响程度大于连通性的影响。④高铁区位对不同地区、不同规模城市异地投资的影响呈现差异性,连通性促进资金向东部地区和巨特大城市流动,可达性则能够显著提升西部地区及小城市对异地投资的吸引。

关键词：高铁区位重大基础设施连通性异地投资空间异质性

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A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： wei wei Feng GUAN Xin FANG College of Intelligent Science National University of Defense Technology Naval Research Academy

A metamaterial vibration isolator, termed as wave-insulating isolator, is proposed, which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave insulation. It consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and narrow. The bandgap mechanisms, vibration isolation properties, effects of key parameters, and robustness to complex conditions are clarified. As experimentally demonstrated, the wave-insulating isolator can improve the vibration insulation in the ranges of [50 Hz, 180 Hz] and [260 Hz,400 Hz] by 15 dB and 25 dB, respectively, in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate O328 34A30 74K20

儿童特应性皮炎患儿血清IP-10和CXCR3水平及临床意义

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国际检验医学杂志 2023年第18期44卷 2254-2257页

作者：许颖尉景娟孙伟首都医科大学附属北京友谊医院临床检验中心北京100050

目的探讨儿童特应性皮炎(AD)患儿血清干扰素-γ诱导蛋白-10(IP-10)和趋化因子受体3(CXCR3)水平及临床意义。方法选取2020年3月至2022年3月在该院诊断为AD的114例患儿作为AD组,根据特应性皮炎评分(SCORAD)分为轻度组(38例)、中度组(42... 详细信息

目的探讨儿童特应性皮炎(AD)患儿血清干扰素-γ诱导蛋白-10(IP-10)和趋化因子受体3(CXCR3)水平及临床意义。方法选取2020年3月至2022年3月在该院诊断为AD的114例患儿作为AD组,根据特应性皮炎评分(SCORAD)分为轻度组(38例)、中度组(42例)、重度组(34例);同期选择在该院体检健康的108例儿童作为对照组。采用酶联免疫吸附试验(ELISA)检测血清IP-10和CXCR3水平,Pearson法分析AD患儿血清IP-10和CXCR3的相关性,绘制受试者工作特征(ROC)曲线分析IP-10、CXCR3对AD的诊断价值。结果与对照组比较,AD组血清IP-10和CXCR3水平均升高(P<0.05);重度组的IP-10、CXCR3水平和SCORAD评分均高于中度组和轻度组(P<0.05),中度组高于轻度组(P<0.05);相关性分析显示,AD组血清IP-10和CXCR3水平呈正相关(P<0.05);ROC曲线分析显示,二者联合诊断AD的曲线下面积大于IP-10和CXCR3单项诊断(P<0.05)。结论 AD患儿血清IP-10和CXCR3水平均升高,二者联合对AD具有一定的诊断价值。

关键词：特应性皮炎干扰素-γ诱导蛋白-10 趋化因子受体3 儿童

Humic acid-mediated transport of a typical soil passivation remediation product(chloropyromorphite)in saturated porous media

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Journal of Environmental Sciences 2024年第7期141卷 51-62页

作者： Xinying Li Mengjia Zhang Siyuan Li wei wei School of Environment Jiangsu Engineering Lab of Water and Soil Eco-remediationJiangsu Province Engineering Research Center of Environmental Risk Prevention and Emergency Response TechnologyNanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Conversion of labile Pb species into chloropyromorphite(CPY)using phosphorus-bearing amendments was considered to be an ideal strategy in soil passivation ***,the fate and transport of CPY in the soil are poorly *** study aims to fill the knowledge gap by evaluating the fate and transport of CPY under environmentally relevant conditions of humic acid(HA),pH,electrolyte concentration,and species through the saturated sandy *** showed that bare CPY colloids are basically immobile in sandy porous media while the co-existence of HA made the transport of CPY improved by30%-93.5%.Facilitated transport of CPY was attributed to the increased stability of CPY and the repulsive interaction between CPY particles and sands due to HA *** mobility of CPY was also increased with increasing pH from 5.0 to *** the pH was 9 with a10 mmol/L NaCl background solution,the stronger energy barrier between CPY and sand led to enhanced transport *** divalent Ca^(2+)had a more dramatic effect than monovalent Na^(+)on the aggregation and sedimentation of CPY colloids due to its effectivescreening of the surface charge of CPY and bridging interaction with CPY ***-LandauVerwey-Overbeek theory and attachment efficiency calculation indicated that high energy barriers were responsible for the high mobility of CPY colloids,while the retention of CPY in sands was mainly caused by secondary energy minimum and physically *** findings of this work can help to evaluate the fate of soil passivation remediation products in natural water and soil.

关键词： Chloropyromorphite DLVO theory Stability Saturated porous medium Transport

The Existence of a Meridional Curve in Closed Incompressible Surfaces in Fully Alternating Link Complements

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 73-80页

作者： wei LIN School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina

Menasco showed that a closed incompressible surface in the complement of a non-split prime alternating link in S^(3) contains a circle isotopic in the link complement to a meridian of the *** on this result,he was able to argue the hyperbolicity of non-split prime alternating links in *** et *** that if F■S×I\L is an essential torus,then F contains a circle which is isotopic in S×I\L to a meridian of *** author generalizes his result as follows:Let S be a closed orientable surface,L be a fully alternating link in S×I\If F ■ S×I\L is a closed essential surface,then F contains a circle which is isotopic in S×I\L to a meridian of L.

关键词： Fully alternating Incompressible surfaces Meridionally incompressible

Zeros of Complete Symmetric Polynomials over Finite Fields

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Journal of Systems Science & Complexity 2024年第4期37卷 1772-1788页

作者： CAO wei School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China

Wan and Zhang(2021) obtained a nontrivial lower bound for the number of zeros of complete symmetric polynomials over finite fields,and proposed a problem whether their bound can be *** this paper,the author improves Wan-Zhang's bound from three *** proposed results are based on the estimates related to the number of certain permutations and the value sets of non-permutation polynomials associated to the complete symmetric *** the author believes that there are still possibilities to improve the bounds and hence Wan-Zhang's bound.

关键词： Complete symmetric polynomial finite field permutation polynomial value set

High Speed Sintering:Assessing the Influence of Energy Input on Microstructure and Mechanical Properties of Polyether Block Amide(PEBA)Parts

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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： Jiang-Tao Sun Zhi-Yong Fan Yi-wei Mao wei Li wei Zhu Dao-Sheng Cai Qing-Song wei State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research Centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG Technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA