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人口红利向人才红利转变的政治经济学分析——基于国际分工的不平等交换视角

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经济学家 2024年第10期 54-63页

作者：楼俊超金哲汗浙江大学马克思主义理论创新与传播研究中心

中国的人口红利得益于改革开放的经济体制改革。改革开放后,大量农村人口涌入城市,构成庞大的产业后备军,为经济发展提供了大量劳动力。但随着劳动力再生产成本提高,中国的生育率逐渐下降,人口红利正在消失。不过,中国长期的人口红利为... 详细信息

中国的人口红利得益于改革开放的经济体制改革。改革开放后,大量农村人口涌入城市,构成庞大的产业后备军,为经济发展提供了大量劳动力。但随着劳动力再生产成本提高,中国的生育率逐渐下降,人口红利正在消失。不过,中国长期的人口红利为人才红利的培育提供了坚实基础。中国的人口红利是国际分工的产物,在不平等交换的视角下,实际上将中国置于国际交换中的劣势地位。本文从国际分工的不平等交换切入,剖析了人口红利和人才红利的实质,指明只有从依靠劳动力数量的人口红利转向依靠劳动力质量的人才红利,才能根本改善中国的经济发展前景。因此,必须培养创新型人才,优化创业环境,提高教育质量,倡导终身学习,完善人才政策,加强思想教育,优化产业结构,实现人尽其才,以期推动人口红利向人才红利转变。

关键词：人口红利人才红利不平等交换国际分工

基于倾向性匹配的胆汁反流对胃黏膜影响及CDX2表达分析

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世界华人消化杂志 2024年第4期32卷 261-266页

作者：季怡帆楼晓军浙江中医药大学嘉兴学院联合培养基地浙江省嘉兴市314000 浙江中医药大学附属嘉兴市中医医院消化内科浙江省嘉兴市314000

背景胆汁反流的发病率逐年上升,其对胃粘膜癌前病变的作用存在争议.拟采用倾向性评分匹配方法减少混杂因素的干扰,以探讨胆汁反流对胃黏膜的影响及作用机制.目的通过回顾性研究探讨胆汁反流对胃粘膜损伤的作用,评估其对组织病理学的影... 详细信息

背景胆汁反流的发病率逐年上升,其对胃粘膜癌前病变的作用存在争议.拟采用倾向性评分匹配方法减少混杂因素的干扰,以探讨胆汁反流对胃黏膜的影响及作用机制.目的通过回顾性研究探讨胆汁反流对胃粘膜损伤的作用,评估其对组织病理学的影响以及分子表达.方法收集2023-07/2023-12嘉兴市中医院155例慢性胃炎伴胆汁反流患者,随机选取同期227例慢性胃炎患者为对照组.通过倾向性评分匹配(propensity score matching,PSM)调整混杂因素后,依据新悉尼系统行组织学分级,并以免疫组化方法检测胃粘膜尾型同源框基因2(caudal type homeobox 2,CDX2)表达,分析两组胃粘膜组织病理学改变以及与CDX2表达相关性.结果PSM 1:1匹配后两组基线资料无统计学差异,匹配后慢性胃炎伴胆汁反流组胃黏膜慢性炎症反应、炎症活动性、萎缩、肠上皮化生(intestinal metaplasia,IM)严重程度均高于慢性胃炎组,差异有统计学意义(P<0.05).Spearman相关性检验结果显示CDX2阳性表达与IM显著正相关(r=0.629,P<0.01),与萎缩、胆汁反流呈正相关(r=0.269,r=0.282,P<0.01).结论胆汁反流可加重胃黏膜损伤,是胃粘膜炎症反应、萎缩、IM的危险因素.同时胆汁反流可能通过影响CDX2表达参与IM过程.

关键词：胆汁反流胃粘膜肠上皮化生 CDX2 倾向性评分匹配

基于Eu^(3+)-生物质碳量子点探针的比率型荧光传感体系检测盐酸四环素

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分析测试学报 2024年第4期43卷 600-606页

作者：李春雨赵卓君白万乔高楼军延安大学化学与化工学院陕西省化学反应工程重点实验室陕西延安716000

该文以橙皮为原料制备的碳量子点(CDs)与铕离子(Eu^(3+))构建双发射比率型荧光探针(Eu^(3+)-CDs)并用于抗生素盐酸四环素的检测。在370 nm激发波长下,Eu^(3+)-CDs荧光探针在425 nm处出现较强的蓝色荧光峰,在617 nm处出现较弱的红色荧光... 详细信息

该文以橙皮为原料制备的碳量子点(CDs)与铕离子(Eu^(3+))构建双发射比率型荧光探针(Eu^(3+)-CDs)并用于抗生素盐酸四环素的检测。在370 nm激发波长下,Eu^(3+)-CDs荧光探针在425 nm处出现较强的蓝色荧光峰,在617 nm处出现较弱的红色荧光峰。随着盐酸四环素浓度的逐渐增大,Eu3+与盐酸四环素螯合形成的配合物增多,在425 nm处的CDs荧光(I_(F425))逐渐减弱,而617 nm处铕配合物的荧光(I_(F617))逐渐增强,可基于荧光强度比I_(F617)/I_(F425)的变化对盐酸四环素进行测定。考察了Eu^(3+)的浓度、pH值和反应时间对探针荧光强度的影响。在最佳条件下,该双发射比率型荧光探针对盐酸四环素具有特异性识别能力,荧光强度比(I_(F617)/I_(F425))与盐酸四环素浓度在10~100µmol/L范围内存在良好的线性关系,相关系数r^(2)=0.9926,检出限为5.09µmol/L。该方法成功用于猪肉中盐酸四环素含量的检测,加标回收率为102%~110%,相对标准偏差为0.20%~2.4%,具有较好的实用性。

关键词：双发射比率型荧光探针碳量子点(CDs) 铕离子(Eu^(3+)) 盐酸四环素

A General Synthesis Method for Covalent Organic Framework and Inorganic 2D Materials Hybrids

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Precision Chemistry 2024年第8期2卷 398-405页

作者： Yifan Zhu Yunrui Yan Yuren Feng Yifeng Liu Chen-Yang Lin Qing Ai Tianshu Zhai Bongki Shin Rui Xu Hongchen Shen Qiyi Fang Xiang Zhang Dayanni Bhagwandin Yimo Han Hanyu Zhu Nicholas R.Glavin Pulickel M Ajayan Qilin Li jun lou Department of Materials Science and Nanoengineering Rice UniversityHoustonTexas 77005United States Department of Civil and Environmental Engineering Rice UniversityHoustonTexas 77005United States NSF Nanosystems Engineering Research Center Nanotechnology-Enabled Water Treatment Rice UniversityHoustonTexas 77005United States UES Inc.BeavercreekOhio 45432United States Materials and Manufacturing Directorate Air Force Research LaboratoryWright-Patterson AFBOhio 45433United States Department of Chemistry Rice UniversityHoustonTexas 77005United States

Two-dimensional(2D)inorganic/organic hybrids provide a versatile platform for diverse applications,including electronic,catalysis,and energy storage *** recent surge in 2D covalent organic frameworks(COFs)has introduced an organic counterpart for the development of advanced 2D organic/inorganic hybrids with improved electronic coupling,charge separation,and carrier ***,existing synthesis methods have primarily focused on few-layered film structures,which limits scalability for practical ***,we present a general synthesis approach for a range of COF/inorganic 2D material hybrids,utilizing 2D inorganic materials as both catalysts and inorganic building *** leveraging the intrinsic Lewis acid sites on the inorganic 2D materials such as hexagonal boron nitride(hBN)and transition metal dichalcogenides,COFs with diverse functional groups and topologies can grow on the surface of inorganic 2D *** controlled 2D morphology and excellent solution dispersibility of the resulting hybrids allow for easy processing into films through vacuum *** proof of concept,hBN/COF films were employed as filters for Rhodamine 6G removal under flow-through conditions,achieving a removal rate exceeding 93%.The present work provides a simple and versatile synthesis method for the scalable fabrication of COF/inorganic 2D hybrids,offering exciting opportunities for practical applications such as water treatment and energy storage.

关键词： Covalent organic frameworks Transition-metal dichalcogenides Lewis acid catalysts Hexagonal boron nitride Hybrid Materials

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竹笋营养成分及其提取方法研究进展

世界林业研究 2024年第2期37卷 53-59页

作者：邵琼郭帆李雯卞方圆楼君杨慧敏国家林业和草原局竹子研究开发中心杭州310012 竹林生态与资源利用国家林业和草原局重点实验室杭州310012 杭州市富阳区农业技术推广中心杭州311400

中国竹资源非常丰富,有200多个竹种的竹笋可以食用,是世界上最大的竹笋生产和出口国。随着人们对绿色食品需求的增加,竹笋资源的开发利用已引起各国学者的关注。文中综述竹笋营养成分的组成、特点及不同竹种之间的差异,分析了竹笋营养... 详细信息

中国竹资源非常丰富,有200多个竹种的竹笋可以食用,是世界上最大的竹笋生产和出口国。随着人们对绿色食品需求的增加,竹笋资源的开发利用已引起各国学者的关注。文中综述竹笋营养成分的组成、特点及不同竹种之间的差异,分析了竹笋营养成分中膳食纤维、多糖、蛋白质、氨基酸、甾醇、黄酮等在改善消化系统、降低心血管疾病、控制血糖、抗炎、抗氧化等方面的作用机制和健康功效,并探讨主要营养成分提取技术和加工方法,最后提出竹笋次生代谢产物高值化利用、开发具有抗氧化等多功能竹笋新产品、新设备、新工艺等研究方向,以为竹笋产品深加工提供参考。

关键词：竹笋营养成分高值化利用

超声谐振式盲文点显胞元的挤压膜建模及实验研究

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振动工程学报 2024年第2期37卷 218-225页

作者：赵琪啸李国平韩凯项四通魏燕定娄军强宁波大学机械工程与力学学院浙江宁波315211 浙江大学浙江省先进制造技术重点研究实验室浙江杭州310027

目前传统的盲文书籍已经难以满足盲人的阅读需求,本文基于超声振动产生的挤压膜提出了一种超声谐振式盲文点显胞元。理论推导了决定挤压膜气动力学特性的Reynolds方程,利用挤压膜的“活塞效应”得到了输出托浮力的力学模型及近似解,利... 详细信息

目前传统的盲文书籍已经难以满足盲人的阅读需求,本文基于超声振动产生的挤压膜提出了一种超声谐振式盲文点显胞元。理论推导了决定挤压膜气动力学特性的Reynolds方程,利用挤压膜的“活塞效应”得到了输出托浮力的力学模型及近似解,利用搭建的实验平台开展了盲文点显胞元的振动特性测试和输出性能测试。结果表明:该盲文点显胞元的谐振频率为30.8 kHz,激励电压峰峰值在130~200 Vpp时,可以形成稳定且具备一定托浮能力的挤压膜。理论计算值与实验实测数据基本吻合,实验中三种不同质量的试样可被托起13.92~47.71μm的高度,盲文点显胞元具备足够的输出性能。

关键词：超声振动盲文点显压电作动器挤压膜效应

Surface Dislocation Nucleation Mediated Deformation and Ultrahigh Strength in Sub-10-nm Gold Nanowires

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Nano Research 2011年第12期4卷 1261-1267页

作者： Yang Lu jun Song Jian Yu Huang jun lou Department of Mechanical Engineering ＆ Materials Science Rice University Houston TX 77005 USA Department of Mining ＆ Materials Engineering McGill University Montreal QC H3A 2B2 Canada Center for Integrated Nanotechnologies （C1NT） Sandia National Laboratories Albuquerque NM 87185 USA Present address： Department of Materials Science and Engineering MIT Cambridge MA 02139 USA

The plastic deformation and the ultrahigh strength of metals at the nanoscale have been predicted to be controlled by surface dislocation nucleation. In situ quantitative tensile tests on individual 〈111〉 single crystalline ultrathin gold nanowires have been performed and significant load drops observed in stress-strain curves suggest the occurrence of such dislocation nucleation. High-resolution transmission electron microscopy （HRTEM） imaging and molecular dynamics simulations demonstrated that plastic deformation was indeed initiated and dominated by surface dislocation nucleation, mediating ultrahigh yield and fracture strength in sub-lO-nm gold nanowires.

关键词： Nanowires in situ transmission electron microscope (TEM) mechanical characterization dislocation nucleation plasticity

Two dimensional heterostructure： perfect platform for exploring interface interaction

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Science Bulletin 2017年第6期62卷 381-382页

作者： Jiangtan Yuan Weibing Chen jun lou Department of Materials Science and Nano Engineering Rice University Houston TX 77005 USA

Two-dimensional(2D)materials have been attracting great amount of attentions from researchers worldwide due to their exotic mechanical,optical,electrical,thermal and catalytic properties,which could enable their potential applications in future multifunctional *** interests in 2D materials were initially inspired by the successful exfoliation and characterization

关键词： Mo WS

Evaluation of a risk factor scoring model in screening for undiagnosed diabetes in China population

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第10期12卷 846-852页

作者： Jian-jun DONG Neng-jun lou Jia-jun ZHAO Zhong-wen ZHANG Division of Endocrinology Department of Medicine Qilu Hospital of Shandong University Jinan 250012 China Division of Endocrinology Department of Medicine the Second Hospital of Shandong University Jinan 250033 China Division of Endocrinology Department of Medicine Shandong Provincial Qianfoshan Hospital Jinan 250014 China Division of Endocrinology Department of Medicine Provincial Hospital Affiliated to Shandong University Jinan 250021 China

Objective:To develop a risk scoring model for screening for undiagnosed type 2 diabetes in Chinese ***:A total of 5348 subjects from two districts of Jinan City,Shandong Province,China were *** A (2985) included individuals from east of the city and Group B (2363) from west of the *** questionnaires and a standard oral glucose tolerance test (OGTT) were completed by all *** on the stepwise logistic regression analysis of Group A,variables were selected to establish the risk scoring *** validity and effectiveness of this model were evaluated in Group ***:Based on stepwise logistic regression analysis performed with data of Group A,variables including age,body mass index (BMI),waist-to-hip ratio (WHR),systolic pressure,diastolic pressure,heart rate,family history of diabetes,and history of high glucose were accepted into the risk scoring *** risk for having diabetes increased along with aggregate *** Youden index was closest to 1,the optimal cutoff value was set up at *** this point,the diabetes risk scoring model could identify diabetes patients with a sensitivity of 83.3% and a specificity of 66.5%,making the positive predictive value 12.83% and negative predictive value 98.53%.We compared our model with the Finnish and Danish model and concluded that our model has superior validity in Chinese ***:Our diabetes risk scoring model has satisfactory sensitivity and specificity for identifying undiagnosed diabetes in our population,which might be a simple and practical tool suitable for massive diabetes screening.

关键词： Diabetes mellitus Screening Questionnaire Risk factor score