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Chinese Chemical Letters 2013年第9期24卷 849-852页

作者： Lei Chen Bin-Dong Li Qiu-xia xu Da-Bin Liu Chemical Engineering College Nanjing University of Science and Technology

A silica gel supported cobalt（lI） Schiff base complex was synthesized and used for the oxidation of alkyl aromatics using molecular oxygen as an oxidant under atmosphere pressure. The catalyst shows a high conversion of alkyl aromatics and selectivity to benzylic ketones, and could be reused at least 5 times without significant loss of catalytic activity.

关键词： Schiff base complex Aerobic oxidation Alkyl aromatics Supported catalyst

Association between central obesity and executive function as assessed by stroop task performance:A functional near-infrared spectroscopy study

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Journal of Innovative Optical Health Sciences 2018年第1期11卷 37-46页

作者： Zhangyan Deng Qin Huang Jiaai Huang Weixia Zhang Changzhu Qi xia xu Graduate School Wuhan Sports University Wuhan 430079P.R.China College of Health Science Wuhan Sports University Wuhan 430079P.R.China Hubei Key Laboratory of Exercise Training and Monitoring Wuhan Sports University 461 Luoyu Road Wuhan 430079P.R.China

Recent studies have suggested a link between executive function(EF)and *** oftenadopt body mass index(BM),which reflects the distribution of subcutaneous fat,as the solemarker of obesity;however,BMI is inappropriate to distinguish central obesity,which indicatesthe centralized distribution of visceral *** fat compared with subcutaneous fat repre-sents greater relative lipid turnover and may increase the risk of cognitive decline in older ***,the relationship between EF and central obesity is largely unknown,particularly inyoung ***,we used waist circumference(WC)as a marker of central obesity andinvestigated diferent sensitivities between BMI and WC in the brain function.A total of 26healthy young adults(aged 18-25 years;42%female)underwent functional near-infrared spec-troscopy *** was assessed using the Stroop task,which is a classical measurementof EF.A significant Stroop effect was observed in the behavioral and hemodynamic ***,we observed that behavioral interference on the Stroop task varied much more insubjects with higher BMI and WC than those subjects with *** BMI and WC wereassociated with a decreased hemodynamic response during the Stroop task specifically in the pre-frontal cortex(PFC).Compared to BMI,WC was more closely connected with inhibitory controland revealed right lateralized PFC *** findings suggest that WC is a reliable indicatorof brain function in young adults and propose a relationship bet ween EF and central obesity.

关键词： Executive function central obesity fNIRS young adult

TNFR2 expression on non-bone marrow-derived cells is crucial for lipopolysaccharide-induced septic shock and downregulation of soluble TNFR2 level in serum

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Cellular & Molecular Immunology 2011年第2期8卷 164-171页

作者： Lijie Rong Jingjing Deng xiaopu Zhao xiaoman Liu xia xu Zhihai Qin National Laboratory of Biomacromolecules China-Japan Joint Laboratory of Structural Virology and ImmunologyInstitute of BiophysicsChinese Academy of SciencesBeijingChina Graduate University of Chinese Academy of Sciences Institute of BiophysicsBeijingChina

Persistently high serum levels of soluble tumor-necrosis factor(TNF)receptor 2(sTNFR2)have been observed in septic shock and many inflammatory ***,its origin and regulation during these pathological processes are still largely *** this study,murine bone marrow(BM)chimeras selectively expressing TNFR2 on either BM-derived or non-BM-derived cells were generated and challenged with lipopolysaccharide(LPS).The results show that TNFR2 expression on non-BM-derived cells is crucial for both the sensitivity of mice to LPS and the downregulation of sTNFR2 in *** importantly,sTNFR2 was released from both BM-and non-BM-derived ***-BM TNFR1 expression influenced the sensitivity of mice to LPS challenge but not the level of serum *** results provide the first in vivo evidence for the origin and regulation of sTNFR2 in serum and could aid in the development of novel anti-TNF strategies against septic shock.

关键词： LPS non-BM-derived cells sTNFR2

基于机器学习的人工关节置换术后医院感染预测模型的构建与评价

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中华医院感染学杂志 2024年第12期34卷 1826-1830页

作者：甘文思干铁儿杨西帆余旭霞杨璐李文渊浙江大学公共卫生学院大数据健康科学系(浙江大学医学院附属第二医院临床大数据与统计中心) 浙江杭州310058 温州市中西医结合医院感染管理科浙江温州325000 浙江中医药大学附属第一医院(浙江省中医院)感染管理科浙江杭州310000

目的构建一种基于机器学习的预测模型,用于人工关节置换术后医院感染的预测.方法选择浙江省杭州市某三甲医院2017年1月-2022年11月进行人工关节置换手术的1800例住院患者作为研究对象,将数据集以3:1的比例随机分成训练集(1350例)和测试... 详细信息

目的构建一种基于机器学习的预测模型,用于人工关节置换术后医院感染的预测.方法选择浙江省杭州市某三甲医院2017年1月-2022年11月进行人工关节置换手术的1800例住院患者作为研究对象,将数据集以3:1的比例随机分成训练集(1350例)和测试集(450例).在训练集中应用递归特征消除方法进行自变量筛选,通过网格搜索方法确定逻辑回归、支持向量机(SVM)、决策树(DT)、极端梯度提升(XGBoost)和随机森林(RF)等五类模型的最佳参数.使用敏感度(TPR)、阳性预测值(PPV)、特异度(TNR)、阴性预测值(NPV)、F1分数、准确度和曲线下面积(AUC)等指标来评估模型性能,确定较优机器学习模型,并采用沙普利加性解释(SHAP)方法对较优模型中的变量重要性进行解释.结果1800例参与者中102例发生感染,发生率为5.67%;逻辑回归、DT、RF、SVM和XGBoost等五个模型在训练集中的AUC值达0.92、0.89、0.98、0.70、0.98;测试集中AUC值则分别为0.85、0.78、0.86、0.63、0.88;XGBoost、RF模型为较优的机器学习模型.SHAP结果显示围手术期抗菌药物使用天数、手术时间、年龄、国家医院感染监控系统(NNIS)评分、失血量是较为重要的预测因子.结论本研究建立了基于机器学习算法的人工关节置换术后医院感染风险预测模型,并比较了多种预测模型的效能,其中XGBoost、RF模型的总体性能较优,有利于及时准确地识别人工关节置换术后医院感染高危患者并实施有效的干预措施.

关键词：人工关节置换机器学习预测模型术后医院感染

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Nutrient resorption and stoichiometric responses of poplar(Populus deltoids)plantations to N addition in a coastal region of eastern China

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Journal of Plant Ecology 2021年第4期14卷 591-604页

作者： Dalong Jiang Qian Li Qinghong Geng Menghua Zhang Chonghua xu Guoqing Hu Caiqin Shen Honghua Ruan xia xu Department of Ecology Co-Innovation Center for Sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing210037China Advanced Analysis and Testing Center Nanjing Forestry UniversityNanjing 210037China College of Resources and Environment Shandong Agricultural UniversityTai’an 271018China Dongtai Forest Farm Yancheng 224200China

Aims Leaf nutrient resorption is sensitive to changes in soil ***,the effects of N deposition on nutrient resorption efficiency(NuRE)in plant macro-nutrients remain ***(Populus deltoids)is one of the most extensively cultivated hardwood species *** explored general patterns and dominant drivers of NuRE and stoichiometry of poplar plantations in response to N *** We conducted a 4-year N-addition experiment to explore NuRE and stoichiometric responses to N addition in two poplar(***)plantations(8-and 12-year-old stands)in a coastal region of eastern *** measured soil and foliar(green and senesced leaves)concentrations of nitrogen(N),phosphorus(P),potassium(K),calcium(Ca)and magnesium(Mg)for a series of N addition treatments including N_(0)(0 kg N ha^(−1)yr^(−1)),N_(1)(50 kg N ha^(−1)yr^(−1)),N_(2)(100 kg N ha^(−1)yr^(−1)),N_(3)(150 kg N ha^(−1)yr^(−1))and N_(4)(300 kg N ha^(−1)yr^(−1)).Important Findings Consistent for(both)8-and 12-year-old stands,N addition did not affect the NuRE and stoichiometry(with the exception of CaRE and CaRE:MgRE ratio).N resorption efficiency–P resorption efficiency(NRE–PRE)scaling slopes were consistently less than 1.0 under N *** results suggest that NRE generally decouples from PRE within each N ***,these results point to robust control of green leaf nutritional status on nutrient resorption processes as indicated by the positive relationships between NuRE and green leaf nutrient *** findings provided a direct evidence that growth in 12-year-old poplar plantations was N-limited in the coastal region of eastern China.

关键词： nutrient resorption efficiency N addition stoichiometry macro-nutrient green leaf nutrients poplar plantation

The fabrication strategies and enhanced performances of metal-organic frameworks and carbon dots composites: State of the art review

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Chinese Chemical Letters 2023年第3期34卷 7-23页

作者： Yanqiu Zhang Minrui Sun Mingguo Peng Erdeng Du xia xu Chong-Chen Wang School of Environmental and Safety Engineering Changzhou UniversityChangzhou 213164China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Energy Conservation&Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Metal-organic frameworks(MOFs) with large specific surface area, considerable pore volume, controllable structure, and high concentration of active metal sites have been applied widely in researches like catalysis and sensing. However, potential applications of MOFs in both photocatalysis and luminescence sensors are facing major challenges arising from their severe charge recombination, low utilization of solar energy, low quantum yield, limited charge transfer between the metal ions/clusters and the *** studies revealed that rational introduction of carbon dots(CDs) with excellent optical properties,unique quantum confinement and high conductivity can greatly enhance the functions of MOFs. In this paper, typical synthesis methods of these CD-MOF composites as well as their potential applications in photocatalysis and sensing are reviewed with emphasis. Representative examples of these CD-MOF composites are discussed, and key features and advantages of CD-MOF composites that will facilitate future applications are highlighted.

关键词： Carbons dots Metal-organic frameworks Synthesis Photocatalysis Sensors

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废旧沥青混合料厂拌热再生技术综述

现代交通与冶金材料 2024年第4期4卷 23-33,40页

作者：夏旭王鹏飞孙向进赵永利东南大学交通学院江苏南京211189

本文对废旧沥青混合料(RAP)厂拌热再生技术各环节关键技术问题和最新研究成果进行综述。分析了沥青老化机理和老化后的多尺度变化规律,总结基质沥青和SBS改性沥青的再生方法与再生剂研究进展。通过分析RAP的性能特点和变异性,引入了最... 详细信息

本文对废旧沥青混合料(RAP)厂拌热再生技术各环节关键技术问题和最新研究成果进行综述。分析了沥青老化机理和老化后的多尺度变化规律,总结基质沥青和SBS改性沥青的再生方法与再生剂研究进展。通过分析RAP的性能特点和变异性,引入了最新的预处理技术。评述了厂拌热再生沥青混合料和沥青路面的性能特点,对比了间歇式和连续式厂拌设备及工艺,介绍了工程应用情况和效益,明确了厂拌热再生技术在节能减排、经济环保方面的优势。本文在分析现有厂拌热再生技术最新研究进展的同时,提出了存在的问题和未来发展方向,助力厂拌热再生技术的革新和推广应用。

关键词：废旧沥青混合料厂拌热再生再生剂路用性能

Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： Yu-Zhao Yang Cheng xu Li-xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

PBX1 attributes as a determinant of connexin 32 downregulation in Helicobacter pylori-related gastric carcinogenesis

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World Journal of Gastroenterology 2017年第29期23卷 5345-5355页

作者： xiao-Ming Liu Can-xia xu Lin-Fang Zhang Li-Hua Huang Ting-Zi Hu Rong Li Xiu-Juan xia Lin-Yong xu Ling Luo xiao-xia Jiang Ming Li Department of Gastroenterology the Third Xiangya Hospital of Central South University Center for Medical Experiments the Third Xiangya Hospital of Central South University Department of Medical Statistics Xiangya School of Public Health Central South University

AIM To clarify the mechanisms of connexin 32 (Cx32) downregulation by potential transcriptional factors (TFs) in Helicobacter pylori (H. pylori)-associated gastric carcinogenesis. METHODS Approximately 25 specimens at each developmental stage of gastric carcinogenesis [non-atrophic gastritis, chronic atrophic gastritis, intestinal metaplasia, dysplasia and gastric carcinoma (GC)] with H. pylori infection [H. pylori (+)] and 25 normal gastric mucosa (NGM) without H. pylori infection [H. pylori (-)] were collected. After transcriptional factor array analysis, the Cx32 and PBX1 expression levels of H. pylori-infected tissues from the developmental stages of GC and NGM with no H. pylori infection were measured by real-time polymerase chain reaction (RT-PCR) and Western blot analysis. Regarding H. pylori-infected animal models, the Cx32 and PBX1 mRNA expression levels and correlation between the gastric mucosa from 10 Mongolian gerbils with long-term H. pylori colonization and 10 controls were analyzed. PBX1 and Cx32 mRNA and protein levels were further studied under the H. pylori-infected condition as well as PBX1 overexpression and knockdown conditions in vitro. RESULTS Incremental PBX1 was first detected by TF microarray in H. pylori-related gastric carcinogenesis. The identical trend of PBX1 and Cx32 expression was confirmed in the developmental stages of H. pylori-related clinical specimens. The negative correlation of PBX1 and Cx32 was confirmed in H. pylori-infected Mongolian gerbils. Furthermore, decreased PBX1 expression was detected in the normal gastric epithelial cell line GES-1 with H. pylori infection. Enforced overexpression or RNAi-mediated knockdown of PBX1 contributed to the diminished or restored Cx32 expression in GES-1 and the gastric carcinoma cell line BGC823, respectively. Finally, dual-luciferase reporter assay in HEK293T cells showed that Cx32 promoter activity decreased by 30% after PBX1 vector co-transfection, indicating PBX1 as a transcriptio

关键词： Helicobacter pylori Inflammation-carcinoma chain Connexin 32 PBX1 Carcinogenesis

东北春播区糜子核心种质及其DNA分子身份证构建

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作物学报 2024年第5期50卷 1181-1192页

作者：丁艺冰辛旭霞冯智尊曹越郭娟 Dipak K SANTRA 王瑞云陈喜明山西农业大学玉米研究所中国山西忻州034000 山西农业大学农学院中国山西太谷030801 内布拉斯加大学林肯分校农艺系小宗粮豆研究与推广中心美国内布拉斯加州斯克茨布拉夫69361 山西农业大学杂粮种质创新与分子育种山西省重点实验室中国山西太原030000

本研究以500份东北春播区糜子资源为材料,利用169个SSR标记,采用UPGMA聚类分组,进行分层抽样,构建核心种质,同时应用ID Analysis 4.0软件构建分子身份证。利用等位基因数(Na)等遗传多样性衡量指标评估核心种质的遗传差异,并利用PCOA分... 详细信息

本研究以500份东北春播区糜子资源为材料,利用169个SSR标记,采用UPGMA聚类分组,进行分层抽样,构建核心种质,同时应用ID Analysis 4.0软件构建分子身份证。利用等位基因数(Na)等遗传多样性衡量指标评估核心种质的遗传差异,并利用PCOA分析核心种质。结果表明,对169对SSR引物进行筛选,发现30对多态性好,利用30对SSR引物构建的糜子核心种质包含190份材料,占全部种质的38%,全部种质与核心种质的均检测出91个等位变异,保留了100%等位基因;有效等位基因数为2.2977~2.9975和2.2872~3.0173,平均值分别为2.8198和2.8297;Shannon多样性指数为0.9532~1.0990和0.9535~1.1162,平均值为1.0645和1.0667;观测杂合度为0.3434~0.8037和0.3162~0.7849,平均值为0.5399和0.5359;期望杂合度为0.5654~0.6672和0.5645~0.6707,平均值为0.6448和0.6473;Nei’s基因多样性指数为0.5648~0.6664和0.5628~0.6686,平均值为0.6441和0.6452;多态性信息含量为0.6657~0.8356和0.6493~0.8340,平均值为0.7974和0.7944。全部种质与核心种质的分子标记的相关指标进行t检验,结果无显著性差异,且PCOA分析表明核心种质与全部种质具有相似的遗传多样性和群体结构,同时发现8个SSR标记(RYW5、RYW8、RYW16、RYW28、RYW40、RYW53、RYW62和RYW67)可区分190份核心种质,构建了东北糜子核心种质的分子身份证。

关键词：糜子东北春播区 SSR 核心种质 DNA分子身份证