Purpose:The 5th Plenary Session of the 19th Communist Party of China(CPC)Central Committee clearly states that developing science and technology through self-reliance and self-strengthening provides the strategic unde...Purpose:The 5th Plenary Session of the 19th Communist Party of China(CPC)Central Committee clearly states that developing science and technology through self-reliance and self-strengthening provides the strategic underpinning for China’s development.Based on this background,this paper explores a metric model for assessing national scientific research strength through collaboration on research papers.Design/methodology/approach:We propose a novel metric model for assessing national scientific research strength,which sets two indicators,national scientific self-reliance(SR)and national academic contribution(CT),to reflect“self-reliance”and“self-strengthening”respectively.Taking the research papers in quantum technology as an example,this study analyzes the scientific research strength of various countries around the world,especially China in quantum technology.Findings:The results show that the research of quantum technology in China has always been relatively independent with fewer international collaboration papers and located in a more marginal position in cooperation networks.China’s academic contribution(CT)to global quantum technology research is increasing and has been greater than that of the United States in 2020.Combining the two indicators,CT and SR,China’s research strength in the quantum field closely follows the United States,and the United States is the most powerful with high research autonomy.Research limitations:This paper only reflects China’s scientific research strength in quantum technology from collaboration on research papers and doesn’t consider the segmentation of quantum technology and the industrial upstream and downstream aspects,which need further study.Practical implications:The model is helpful to better understand the national scientific research strength in a certain field from“self-reliance”and“self-strengthening”.ScienceOriginality/value:We propose a novel metric model to measure the national scientific research strength from the perspective of“self-reliance”and“self-strengthening”,which provides a solid basis for the assessment of the strength level of scientific research in countries/regions and institutions.展开更多
目的:探讨重症监护病房(intensive care unit,ICU)获得性肌无力(ICU acquired weakness,ICUAW)患者肌肉超声回声与血浆炎性因子的相关性,以及其对ICUAW的诊断价值和预后的预测价值。方法:选择重庆市急救医疗中心ICU住院患者,分别在第1、...目的:探讨重症监护病房(intensive care unit,ICU)获得性肌无力(ICU acquired weakness,ICUAW)患者肌肉超声回声与血浆炎性因子的相关性,以及其对ICUAW的诊断价值和预后的预测价值。方法:选择重庆市急救医疗中心ICU住院患者,分别在第1、3、7天使用床旁超声检测患者肌肉回声,获得的总体肌肉回声评分(global muscle echogenicity score,GEM),测定血清白细胞介素-6(interleukin-6,IL-6)和降钙素原(procalcitonin,PCT)浓度,采用医学研究理事会肌力评分法(medical research council scales,MRC-ss)评估肌肉力量。根据患者入ICU第7天MRC-ss评分将患者分为ICUAW组和非ICUAW组,分析比较2组患者GEM、IL-6、PCT的差异及各指标的相关性。利用受试者工作特征(receiver operator characteristic,ROC)曲线分析以上参数对ICUAW诊断效能,分析GEM、IL-6、PCT对ICUAW患者的预测预后价值。结果:ICUAW组第3天GEM、第7天IL-6浓度、GEM高于非ICUAW组(P<0.05)。GEM与第7天IL-6水平呈正相关(r=0.221),第7天GEM与MRC-ss评分呈负相关(r=-0.581)。ROC曲线分析显示,第7天GEM对ICUAW有诊断预测价值,ROC曲线下面积(area under the curve,AUC)为0.838,使用GEM、IL-6、PCT联合诊断,AUC=0.885(P<0.05)。ICUAW组Barthel指数评分(Barthel index,BI)低于非ICUAW组,ICUAW组中总体肌肉超声回声评分(global muscle echogenicity score,GEM)高的患者BI低于GEM低的患者(P<0.05)。结论:ICU住院患者GEM与IL-6、PCT浓度相关,其对ICUAW具有一定的诊断价值,并能够预测ICUAW患者的预后。展开更多
针对水泥稳定级配碎石混合料配合设计方法的不足,引入混合料目标级配的概念,提出填充料、嵌挤料、骨架料等配合比设计专用名词。以广东省普遍应用的水泥稳定级配碎石基层混合料级配范围为基础,采用统计归纳的方法,建立9条运营良好的高...针对水泥稳定级配碎石混合料配合设计方法的不足,引入混合料目标级配的概念,提出填充料、嵌挤料、骨架料等配合比设计专用名词。以广东省普遍应用的水泥稳定级配碎石基层混合料级配范围为基础,采用统计归纳的方法,建立9条运营良好的高速公路花岗岩类混合料填充料、嵌挤料、骨架料等相关通过率与7 d无侧限强度关系,并拟合各强度影响因素与无侧限强度之间的关系(校正决定系数Adj R 2=0.9178),构建了花岗岩类水泥稳定级配碎石配合比设计方法。新的配合比设计方法解决了水泥稳定级配碎石基层混合料级配设计目标不明确、经验要求高、设计工作量大等问题,且可在设计初期预估无侧限强度。展开更多
As most Mg alloy products are now produced by a casting process,the development of high strength cast Mg alloys can promote their further applications and has already become one of the hot research areas of Mg alloys....As most Mg alloy products are now produced by a casting process,the development of high strength cast Mg alloys can promote their further applications and has already become one of the hot research areas of Mg alloys.The present paper reviews the strengthening mechanisms,tensile properties and modification results of commercial high strength cast Mg alloys;as well as the development of Mg-Gd,Mg-Nd and Mg-Sn based alloys.It concludes that precipitation strengthening is the most important strengthening mechanism in high strength cast Mg alloys,which contributes more than 60%of yield strength in solution&peak-aged(T6)cast Mg alloys.For the yield strength,the alloys follow the sequence of Mg-Gd(Y)-Ag>Mg-Gd(Y)-Zn>Mg-Gd-Y/Sm/Nd>Mg-Y-Nd(WE series)>ZK61>Mg-Nd>AZ91>Mg-Sn.Mg-Gd(Y)-Ag based alloys are the strongest cast Mg alloys at present,followed by Mg-Gd(Y)-Zn based alloys.The high yield strengths of Mg-Gd(Y)-Ag and Mg-Gd(Y)-Zn cast alloys are due to the co-precipitation of basal and prismatic meta-stable phases.展开更多
基金supported by National Key R&D Program of China(Grant No.2019YFA0707201)the open fund of ISTIC-Springer Nature Joint Lab for Open Science(Grant No.HX20211292).
文摘Purpose:The 5th Plenary Session of the 19th Communist Party of China(CPC)Central Committee clearly states that developing science and technology through self-reliance and self-strengthening provides the strategic underpinning for China’s development.Based on this background,this paper explores a metric model for assessing national scientific research strength through collaboration on research papers.Design/methodology/approach:We propose a novel metric model for assessing national scientific research strength,which sets two indicators,national scientific self-reliance(SR)and national academic contribution(CT),to reflect“self-reliance”and“self-strengthening”respectively.Taking the research papers in quantum technology as an example,this study analyzes the scientific research strength of various countries around the world,especially China in quantum technology.Findings:The results show that the research of quantum technology in China has always been relatively independent with fewer international collaboration papers and located in a more marginal position in cooperation networks.China’s academic contribution(CT)to global quantum technology research is increasing and has been greater than that of the United States in 2020.Combining the two indicators,CT and SR,China’s research strength in the quantum field closely follows the United States,and the United States is the most powerful with high research autonomy.Research limitations:This paper only reflects China’s scientific research strength in quantum technology from collaboration on research papers and doesn’t consider the segmentation of quantum technology and the industrial upstream and downstream aspects,which need further study.Practical implications:The model is helpful to better understand the national scientific research strength in a certain field from“self-reliance”and“self-strengthening”.ScienceOriginality/value:We propose a novel metric model to measure the national scientific research strength from the perspective of“self-reliance”and“self-strengthening”,which provides a solid basis for the assessment of the strength level of scientific research in countries/regions and institutions.
文摘目的:探讨重症监护病房(intensive care unit,ICU)获得性肌无力(ICU acquired weakness,ICUAW)患者肌肉超声回声与血浆炎性因子的相关性,以及其对ICUAW的诊断价值和预后的预测价值。方法:选择重庆市急救医疗中心ICU住院患者,分别在第1、3、7天使用床旁超声检测患者肌肉回声,获得的总体肌肉回声评分(global muscle echogenicity score,GEM),测定血清白细胞介素-6(interleukin-6,IL-6)和降钙素原(procalcitonin,PCT)浓度,采用医学研究理事会肌力评分法(medical research council scales,MRC-ss)评估肌肉力量。根据患者入ICU第7天MRC-ss评分将患者分为ICUAW组和非ICUAW组,分析比较2组患者GEM、IL-6、PCT的差异及各指标的相关性。利用受试者工作特征(receiver operator characteristic,ROC)曲线分析以上参数对ICUAW诊断效能,分析GEM、IL-6、PCT对ICUAW患者的预测预后价值。结果:ICUAW组第3天GEM、第7天IL-6浓度、GEM高于非ICUAW组(P<0.05)。GEM与第7天IL-6水平呈正相关(r=0.221),第7天GEM与MRC-ss评分呈负相关(r=-0.581)。ROC曲线分析显示,第7天GEM对ICUAW有诊断预测价值,ROC曲线下面积(area under the curve,AUC)为0.838,使用GEM、IL-6、PCT联合诊断,AUC=0.885(P<0.05)。ICUAW组Barthel指数评分(Barthel index,BI)低于非ICUAW组,ICUAW组中总体肌肉超声回声评分(global muscle echogenicity score,GEM)高的患者BI低于GEM低的患者(P<0.05)。结论:ICU住院患者GEM与IL-6、PCT浓度相关,其对ICUAW具有一定的诊断价值,并能够预测ICUAW患者的预后。
文摘针对水泥稳定级配碎石混合料配合设计方法的不足,引入混合料目标级配的概念,提出填充料、嵌挤料、骨架料等配合比设计专用名词。以广东省普遍应用的水泥稳定级配碎石基层混合料级配范围为基础,采用统计归纳的方法,建立9条运营良好的高速公路花岗岩类混合料填充料、嵌挤料、骨架料等相关通过率与7 d无侧限强度关系,并拟合各强度影响因素与无侧限强度之间的关系(校正决定系数Adj R 2=0.9178),构建了花岗岩类水泥稳定级配碎石配合比设计方法。新的配合比设计方法解决了水泥稳定级配碎石基层混合料级配设计目标不明确、经验要求高、设计工作量大等问题,且可在设计初期预估无侧限强度。
基金supported by the National Natural Science Foundation of China(51201103&51304135)the Specialized Research Fund for the Doctoral Program of Higher Education(20110073120008)+2 种基金the New Century Excellent Talents in University of Ministry of Education of China(NCET-11-0329)the Program of Shanghai Subject Chief of Engineering(14XD1425000)the Assembly Pre-research Project(51312030706)
文摘As most Mg alloy products are now produced by a casting process,the development of high strength cast Mg alloys can promote their further applications and has already become one of the hot research areas of Mg alloys.The present paper reviews the strengthening mechanisms,tensile properties and modification results of commercial high strength cast Mg alloys;as well as the development of Mg-Gd,Mg-Nd and Mg-Sn based alloys.It concludes that precipitation strengthening is the most important strengthening mechanism in high strength cast Mg alloys,which contributes more than 60%of yield strength in solution&peak-aged(T6)cast Mg alloys.For the yield strength,the alloys follow the sequence of Mg-Gd(Y)-Ag>Mg-Gd(Y)-Zn>Mg-Gd-Y/Sm/Nd>Mg-Y-Nd(WE series)>ZK61>Mg-Nd>AZ91>Mg-Sn.Mg-Gd(Y)-Ag based alloys are the strongest cast Mg alloys at present,followed by Mg-Gd(Y)-Zn based alloys.The high yield strengths of Mg-Gd(Y)-Ag and Mg-Gd(Y)-Zn cast alloys are due to the co-precipitation of basal and prismatic meta-stable phases.