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两种路径置入完全植入式静脉输液港远期并发症发生情况的Meta分析

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广西医学 2020年第20期42卷 2685-2694页

作者：袁琳丽傅荣崔博南京大学医学院附属鼓楼医院内科江苏省南京市210093

目的系统分析经颈内静脉和锁骨下静脉置入完全植入式静脉输液港远期并发症的发生情况。方法计算机检索万方、维普、知网、中国生物医学文献数据库以及PubMed、Web of Science、Embase和Cochrane library数据库,搜集关于颈内静脉置入与... 详细信息

目的系统分析经颈内静脉和锁骨下静脉置入完全植入式静脉输液港远期并发症的发生情况。方法计算机检索万方、维普、知网、中国生物医学文献数据库以及PubMed、Web of Science、Embase和Cochrane library数据库,搜集关于颈内静脉置入与锁骨下静脉置入完全植入式静脉输液港远期并发症发生率的随机对照试验或队列研究。筛选文献后,提取相关资料,采用RevMan 5.3软件进行Meta分析及亚组分析。结果最终纳入20项研究共8530例患者,其中3项随机对照研究,17项队列研究。Meta分析结果显示,两种植入路径的导管感染发生率、输液港部位感染发生率和导管相关性血栓发生率差异无统计学意义(均P>0.05),而颈内静脉组的导管断裂发生率、导管移位发生率、导管功能障碍发生率低于锁骨下静脉组(均P0.05),而颈内静脉组的导管移位发生率和导管功能障碍发生率均低于锁骨下静脉组(均P0.05),而颈内静脉组的导管相关性血栓发生率、导管断裂发生率、导管移位发生率和导管功能障碍发生率均低于锁骨内静脉组(均P<0.05)。结论与经锁骨内静脉置入输液港相比,经颈内静脉置入输液港导管断裂、移位、功能障碍并发症发生率更低。

关键词：完全植入式静脉输液港置入路径锁骨下静脉颈内静脉远期并发症 Meta分析

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AMR语音编解码算法分析及优化

通信技术 2007年第12期40卷 391-393页

作者：黄桃李小文袁李林重庆邮电大学重庆400065

自适应多速率语音编解码技术共有八种速率,每一种速率都是基于代数码本线性预测技术语音编解码算法的。文中参照3GPPTS协议,分析了代数码本线性预测技术的编解码原理,并对其中的关键技术开环基音分析和固定码本搜索提出了优化方法。经... 详细信息

自适应多速率语音编解码技术共有八种速率,每一种速率都是基于代数码本线性预测技术语音编解码算法的。文中参照3GPPTS协议,分析了代数码本线性预测技术的编解码原理,并对其中的关键技术开环基音分析和固定码本搜索提出了优化方法。经过实验验证,改进后的算法降低了运算复杂度,并能获得良好的语音音质。

关键词：自适应多速率代数码本线性预测技术码本搜索

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei li Xue-yuan liu Yong-Min liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong li Jingyi ZHANG Yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Rational design of lipid-activatable NIR-II probes for precisely imaging atherosclerotic plaque

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Science China Chemistry 2025年

作者： Xinyu Xu yuan Ma Hui Cao li Xu Haoming Chen Sulai liu Wei Sun Guosheng Song Xiaobing Zhang State Key Laboratory for Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University Department of Hepatobiliary Surgery/Central Laboratory Hunan Provincial People's Hospital (The First Affiliated Hospital of Hunan Normal University) Department of Cardiology the First Affiliated Hospital of Nanjing Medical University Key Laboratory of Targeted Intervention of Cardiovascular Disease Collaborative Innovation Center for Cardiovascular Disease Translational MedicineNanjing Medical University Shenzhen Research Institute of Hunan University

Atherosclerosis(AS) is a prevalent condition associated with cardiovascular and cerebrovascular diseases, featuring lipid-laden plaque; however, the insufficient resolution and low sensitivity of traditional medical imaging techniques limit their application in lipid imaging. Currently, the second near-infrared(NIR-II) fluorescence imaging offers promising sensitivity and convenience. However, existing probes have limitations in terms of signal-to-background ratio, penetration depth, and tissue scattering. Herein, we use a molecular regulatory strategy to design a lipid-activatable probe Rh-965 with high specificity and NIR-II emission for improved imaging potential in deep tissues. The potential of Rh-965 for imaging plaque lipids in mice with AS is demonstrated by localizing carotid artery plaques using NIR-II imaging. The development of more stable lipid-activated NIR-II probes can significantly enhance atherosclerosis diagnosis and facilitate in vivo imaging in deeper tissues.

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Manufacture the conducting polymer with light

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Science China Chemistry 2025年第1期68卷 8-9页

作者： Yang li Tianyu li Yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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Thermally triggered topological polymerization in diacetylene-functionalized covalent organic framework toward enhanced memristive properties

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Science China Chemistry 2025年

作者： Panke Zhou Yuxing Huang Ziyue Yu Cong Zhang Qian Chen Yiping li Chao lin Xiong Chen State Key Laboratory of Photocatalysis on Energy and Environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COFs), namely Py-EDA and Py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/Py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/OFF current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within Py-BDA, thereby further promoting interlayer charge transfer and separation.

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A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： GUO Xingduo li Yinran li Rennian MA Yulong WEI Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake

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食物因素对桔小实蝇表皮碳氢化合物的影响

环境昆虫学报 2017年第4期39卷 805-812页

作者：雷妍圆林涛何丽云吕利华何余容李群臣广东省农业科学院植物保护研究所/广东省植物保护新技术重点实验室广州510640 华南农业大学农学院广州510642 广东省农业科学院农业生物基因研究中心广州510640

桔小实蝇Bactrocera dorsalis是为害园艺作物的重要检疫性害虫。本研究采用气相色谱-质谱联用(GC-MS)技术,分析了取食3种寄主植物杨桃、番石榴和芒果的桔小实蝇雄成虫表皮碳氢化合物组成和含量,并以人工饲料饲养作为对照进行了比较。结... 详细信息

桔小实蝇Bactrocera dorsalis是为害园艺作物的重要检疫性害虫。本研究采用气相色谱-质谱联用(GC-MS)技术,分析了取食3种寄主植物杨桃、番石榴和芒果的桔小实蝇雄成虫表皮碳氢化合物组成和含量,并以人工饲料饲养作为对照进行了比较。结果表明,4种食物源的桔小实蝇共含有42种表皮碳氢化合物,其碳原子数为C29-C37,主要为正构烷烃、一甲基烷烃和二甲基烷烃。取食杨桃、番石榴和芒果桔小实蝇表皮碳氢化合物种类分别为人工饲料的99.3%、91.4%和98.3%,4种食物源的桔小实蝇表皮碳氢化合物种类基本相同,主成分分析和判别分析可从含量上将各食物源的桔小实蝇区分开。不同食物源引起的差异体现在物质的含量上,而主要的组分种类相对稳定,说明食物因素不影响利用表皮碳氢化合物进行桔小实蝇种的鉴定。因此可提取种内共有物质作为种的特征峰,建立不同食物条件下桔小实蝇的指纹图谱,为检验检疫过程中实蝇种类的鉴定提供数据支持。

关键词：桔小实蝇气相色谱分析表皮碳氢化合物食物因素雄成虫