95 research outputs found

    我国农村剩余劳动力的历史成因

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    当前,“三农”问题是制约我国经济健康运行的瓶颈,而农业剩余劳动力的转移则成了“三农”问题的关键,目前其已处于具有决定意义的新阶段。农业剩余劳动力的成因不同,转移模式也不尽相同。本文从推进和拉动两方面来探究我国农业剩余劳动力出现的历史成因,从而为我国农业剩余劳动力的转移模式提供参考

    货币市场基金风险识别与控制

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    本文从货币市场基金管理人的角度来全面识别货币市场基金面临的各种风险,并提出相应的风险控制对策

    响应面法提取公石松总黄酮工艺优化研究

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    目的:采用响应面法优化公石松总黄酮微波提取工艺。方法:先摸索液料比、反应时间、微波功率、反应温度四个微波提取条件,然后依据Box-Benhnken试验设计拟用四因素三水平方法,以公石松总黄酮提取率为响应值进行响应面试验,最后对不同公石松样品的总黄酮进行对比分析。结果:得出最佳提取工艺条件为:液料比30∶1(ml·g-1)、反应时间6.72 min,微波功率699.99 W,反应温度90℃,公石松总黄酮的提取率可达到1.02%。结论:微波提取工艺优化后公石松总黄酮的提取率可达1.02%;公石松叶子中的总黄酮含量高于茎,成熟期的总黄酮含量高于未成熟期。福建省教育厅中青年教师教育科研项目(编号:JAT171141);;漳州卫生职业学院课题项目(编号:ZYZ201701

    The Research of OpenGL Geometric Transformation and Conversion of the Windows Screen Coordinates

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    分析openGL三维图形显示流程,讨论其坐标变换过程,推导了openGL坐标与Windows屏幕坐标的转换关系,给出了在MFC下实现openGL图形编程的方法。By analysing the processes of openGL 3D graphics and discussng it's coordinate alternation process,the thises derives the trans-formation relationship between openGL coordinate and the Windows screen coordinate. Meanwhile it gives the openGL graphical pro-gramming approach under the platform of MFC.福建省教育厅B类课题(JB0527

    失地农民可持续生计的理论模型研究

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    在国内,可持续生计的理论主要用来研究失地农民问题,但大部分此类研究都缺乏理论模型的指导。为了使失地农民可持续生计问题的研究有一个基本的分析框架,本文在前人研究的基础上对失地农民可持续生计的概念模型和图示模型进行了进一步探讨。国家社科基金青年项目“失地农民可持续生计问题研究”(编号:07CZZ025);教育部人文社科研究青年项目“失地农民可持续生计问题研究”(编号:06JC630014);江西省社会科学研究“十一五”规划项目“江西省失地农民就业问题研究”(编号:08SH12)的阶段性成果之

    Analysis of Epistatic and QE Interaction Effects of QTLs for Grain Shape in Rice

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    本研究利用基于明恢86x佳辐占水稻重组自交系(rECOMbInAnT InbrEd lInE,rIl)构建的SSr遗传图谱,总标记数为131。联合两季的稻米粒长(gl)、粒宽(gW)、长宽比(l/W)表型数据,应用混合线性模型方法进行QTl定位,并作加性效应、上位效应以及加性QTl、上位性QTl与环境(QTl-by-EnVIrOnMEnT,QE)的互作效应分析。检测到粒长、粒宽和长宽比的加性效应QTlS分别为6个、4个和4个,贡献率分别为23.67%、21.41%和25.78%;检测到8对粒长的上位性QTlS,5对粒宽的上位性QTlS,2对长宽比的上位性QTlS,贡献率分别为16.75%、22.36%和7.55%;环境互作检测中,发现共有9个加性QTlS和7对上位性QTlS与环境发生了互作。结果表明,上位效应在粒形性状的遗传与加性效应一样起了重要作用,环境互作效应对粒形性状有一定的影响。A linkage map consisting of 131 markers was constructed by using a recombinant inbred line (RIL) population derived from the indica-indica rice cross Minghui86×Jiafuzhan.Quantitative trait loci (QTLs) was located with a mixed linear model (QTLmapper1.6) based on the grain shape parameters such as grain length (GL), grain width (GW) and length-width ratio (L/W), and made analysis of additive effects, epistatic, and the interaction effects of QTL-by-environment (QE).Six, four and four QTLs were detected to have significant additive effects for GL, GW and L/W, and the contribution rate were 23.67%、21.41% and 25.78%, respectively.Eight, five and two pairs of epistatic QTLs with significant additive-by-additive (AA) interaction effects were identified for three traits, and the contribution rate were 16.75%、22.36% and 7.55%, respectively.Significant QE interactions were found for nine additive QTLs and seven pairs of epistatic QTLs.The results indicated that the epistatic effects played an important role on the inheritance of grain shape, and the environmental factor had certain effects on the three traits.福建省自然科学基金项目(X0750053);厦门大学科技创新计划项目(XDKJCX20063004)共同资

    NUMERICAL ANALYSIS OF LOAD-MOMENT INTERACTION DIAGRAM FOR HIGH STRENGTH CONCRETE COLUMN REINFORCED WITH CONCRETE FILLED STEEL TUBE

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    介绍了以圆钢管为钢骨的劲性高强混凝土柱的抗震性能研究的试验概况,在此基础上采用条带有限元法进行了弯矩-轴力相关曲线的数值分析,计算结果与试验结果大致吻合,可以用于确定该类柱在偏压状态下的极限承载力。The general situation of earthquake-resistant behavior experiments of high concrete columns reinforced with concrete filled steel tube is presented.Based on the experimental results,the numerical analysis of load-moment interaction diagram for the columns is completed using strip finite element analysis method.The calculation results are in basic agreement with those of the experimental values,so the numerical analysis method can be used to determine the ultimate bearing capacity of the columns under eccentric compression

    Progress of Organic Chemistry(2011~2012)

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    本文综述了中国大陆地区有机化学研究人员2011至2012年两年内在合成方法学、有机合成化学、元素有机化学以及天然产物化学等领域获得的重要成果。文章中共引用参考文献355篇,其中110多篇手性金属配合物和有机小分子催化的不对称反应、金属催化的碳氢键活化等合成方法学论文和30余篇氟有机化学论文基本来源于德国《应用化学》(国际版)和《美国化学杂志》。本文汇集了中国有机化学家两年中合成的150多个具有生物活性和化学结构多样性的天然产物,其中不乏具有高度挑战性的复杂天然分子。在近两年中中国有机化学家从陆地和海洋的生物体内发现各种不同类型新天然产物90多个。This biennale report reviewed the major achievements of organic chemistry involved to synthetic methodologies,synthetic chemistry,element-organic chemistry,and natural product chemistry in Mainland of China.There were 355 references cited in this report.Among them,about 110 papers related to the synthetic methodologies as well as about 30 papers of organofluorine chemistry reported herein were collected solely from ACIE and JACS.The report presented the synthesis of more than 150 natural products with diverse chemical structures and bioactivities,including some complex molecules with high synthetic challenge as well as the isolation of more than 90 new natural products with various structural types from continental or /and marine creatures,which were reported by Chinese chemists in 2011 ~ 2012

    “推进一流本科教育,提高人才培养质量”的理念、路径与方法(笔谈)

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    建设世界一流大学需要高度重视本科教育。\"推进一流本科教育,提高人才培养质量\"的前提是要理解本科教育的本意,从不同维度反思\"我们需要什么样的本科教育\"\"什么是好的本科教育\"\"如何推进一流本科教育\"等问题。从宏观层面看,本科教育的使命是为了促进每一个大学生\"成才\"和\"成人\"。从现实需求看,一流本科教育不可忽视跨学科人才培养,需要按照学科标准、职业标准和学生标准对专业进行重新分类,为跨学科专业设置、新工科建设以及高校专业设置与调整开辟理论空间。目前,我国本科教育的最大问题是培养目标不明确,面临学术型与应用型的抉择。好的本科教育需要基于本科生\"关键能力\"的培养,彻底消除他们对于专业的陌生感,满足他们对于理智的好奇心,撤除横亘在大学与社会之间的藩篱并激发他们的创新创业精神。具体来说,一流本科教育是一流\"教\"与\"学\"的统一,需要一流的投入和一流的教育管理,需要在教学改革中侧重技术层面的突破。一流本科教育不是一流大学的\"专利\",不是\"一类本科\",没有固定模式,更不能盲目追求学术GDP。对于应用型本科高校而言,在\"一流本科教育\"中要结合学校特点和办学实际,做出异于\"双一流\"建设高校的现实抉择。作为一类特殊性质的高校,中外合作大学在建设一流本科教育的过程中,要在引入国外优质高等教育资源的基础上,强调对相关资源的消化、吸收、融合、创新,从而培养出符合社会主义现代化建设要求的高素质国际化人才。国家社会科学基金教育学一般项目“新时代中国特色高等教育话语体系构建研究”(BIA180200);;教育部国别和区域研究专项资金资助课题“高等学校专业设置规划与质量保障体系研究

    Promotion of proliferation of luminal B breast cancer cells by mesenchymal stem cells and its underlying molecular mechanisms

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    目的分析人脐带间充质干细胞(hUC-MSCs)对Luminal B型乳腺癌细胞生长增殖的影响,并初步探讨其可能的分子机理。方法绿色荧光蛋白(GFP)和荧光素酶共表达慢病毒感染人Luminal B型乳腺癌细胞BT474,并经嘌呤霉素筛选两周后,于荧光显微镜下观察GFP的表达情况,IVIS Kinetic成像系统拍照以观察和记录慢病毒感染后BT474细胞荧光素酶的表达情况;荧光显微镜下直接观察,结合MTS实验分析hUC-MSCs共培养或其浓缩上清处理对GFP和荧光素酶共表达BT474细胞生长增殖的影响;Western blot法检测hUC-MSCs浓缩上清处理对BT474细胞Akt和MAPK信号通路激活情况以及下游细胞周期调控蛋白Cyclin D1表达的影响;常规RT-PCR法检测hUC-MSCs中NRG-1、NRG-2、IGF-Ⅰ、IGF-Ⅱ和EGF等配体的表达。荧光素酶表达强度与细胞数量的相关性经由Excel软件行统计学分析,MTS实验数据则经由SPSS13.0统计软件行统计学分析。结果荧光显微镜和IVIS Kinetic成像系统的观察结果分别证实,GFP和荧光素酶经慢病毒载体系统的介导可在BT474细胞中成功地共表达,且荧光素酶的表达强度与细胞数量呈直线相关。MSCs共培养或其浓缩上清处理均可显著促进Luminal B型乳腺癌细胞BT474的生长增殖,其细胞存活比例分别为各自对照组的148.06%(P<0.005)和147.99%(P<0.001);MSCs浓缩上清处理同时激活BT474细胞内Akt和MAPK信号通路,并上调细胞周期调控蛋白Cyclin D1表达。此外,RT-PCR结果显示,hUC-MSCs中NRG-1和EGF的mRNAs水平呈高表达,而NRG-2、IGF-Ⅰ和IGF-Ⅱ等配体的mRNAs表达也可见。结论 MSCs可通过表达并分泌NRG-1等配体,从而激活Luminal B型乳腺癌细胞BT474的下游Akt和MAPK信号转导通路以上调细胞周期调控蛋白Cyclin D1的表达,进而促进其生长增殖。Objective To investigate the effect of human umbilical cord mesenchymal stem cells(hUC-MSCs) on proliferation of luminal B breast cancer cells and its underlying molecular mechanisms. Methods Human luminal B breast cancer cells BT474 were infected with GFP and luciferase co-expressing lentiviruses and then subjected for selection with Puromycin for 2 weeks. The expression of GFP and luciferase was detected by fluorescent microscopy and IVIS Kinetic image system, respectively. The effect of coculture or treatment with conditioned medium of hUCMSCs on proliferation of BT474 was analyzed with MTS assay. Western blot was carried out to detect the effect of treatment with conditioned medium of hUC-MSCs on the activation of both Akt and MAPK signalings in BT474, as well as the expression of downstream cell cycle regulator Cyclin D1. Regular RT-PCR was applied to analyze the mRNAs expression of ligands such as NRG-1, NRG-2, IGF-Ⅰ, IGF-Ⅱ, and EGF in hUC-MSCs. The correlation between relative luciferase activity and cell number was analyzed with Excel software, while MTS assay data was statistically analyzed with SPSS 13.0 software. Results The co-expression of GFP and luciferase in BT474 via lentiviral expression system was visualized by fluorescent microscopy and IVIS Kinetic image system. The linear correlation between relative luciferase activity and cell number was determined by curve fitting analysis. Coculture or treatment with conditioned medium of hUC-MSC significantly promoted the proliferation of BT474, with survival rates being 148.06 %(P < 0.005)and 147.99 %(P < 0.001)of control, respectively. In addition, treatment with conditioned medium of hUC-MSC was shown to induce activation of both Akt and MAPK signalings, which further upregulated the expression of Cyclin D1. Moreover, high mRNAs expression levels of both NRG-1 and EGF, as well as moderate mRNAs expression levels NRG-2, IGF-Ⅰ, and IGF-Ⅱ were showed by RT-PCR. Conclusion Our results here demonstrated that MSCs may promote the proliferation of luminal B breast cancer cells through paracrine of ligands such as NRG-1, which in turn results in the activation of both Akt and MAPK signalings and upregulation of the expression of Cyclin D1.国家自然科学基金面上项目(81272922);; 福建省自然科学基金面上项目(2016J01577);; 福州总医院院内课题国际合作研究专项(2015G01
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