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基于主成分及聚类分析的药用菊花品种产量与品质综合评价

第四届智能化农业信息技术国际学术会议

作者： tieying xue {2. zhang beijing vocational college of Agriculture Post Code: 102.42.beijing China

＜正＞The key of Chinese agricultural information digitization （AID） is to apply computers to rural *** a developing country of agriculture,a vast group of technically talented people are badly needed,who are welcomed by peasants and are willing to stay in country *** are the features of New Rural Area （NRA） ? That means information digitization enters villages,touches farmers’ life and is applied to agricultural ***, the quantity and quality of higher vocational education （HVE） for computers are pretty essential in Chinese agricultural information digitization process.

关键词： Agricultural information digitization(AID) New Rural Area(NRA) higher vocational education(HVE) agricultural vocational college(AVC) talent standards training curriculum computer case study

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食品工业科技 2024年第5期45卷 271-280页

作者：黄振慈惠婷柳志勇薛玉前任秀霞薛璟祺张秀新枣庄职业学院山东枣庄277800 中国农业科学院蔬菜花卉研究所北京100081

为防止品种混杂,筛选药用或茶用菊花的专用品种,以不同产地来源的8个药用菊花品种16个样品为试材,采用超高效液相色谱法和比色法测定不同产地药用菊花的品质成分含量;并基于主成分分析和聚类分析,对不同产地药用菊花品种产量与品质进行... 详细信息

为防止品种混杂,筛选药用或茶用菊花的专用品种,以不同产地来源的8个药用菊花品种16个样品为试材,采用超高效液相色谱法和比色法测定不同产地药用菊花的品质成分含量;并基于主成分分析和聚类分析,对不同产地药用菊花品种产量与品质进行综合评价。结果表明,不同产地药用菊花品种单株花头数变异系数(39.03%)最大,是构成药用菊花单株花头干重的主要因素(r=0.800),以枣庄红心菊单株花头数(496.50)最多、单株花头干重最高;绿原酸、3,5-O-二咖啡酰基奎宁酸和总黄酮等药效成分在不同来源的样本中差异显著(P<0.05),上述三种成分在滁州产滁菊中相对含量较高,分别为3.75%、8.07%、16.08%,这与其品质成分综合评价结果一致,说明滁州滁菊药效较优。13个性状指标的主成分分析提取出药效因子、高产因子、总黄酮因子和花径因子4个主成分,其累计贡献率为84.34%;综合评价得分排在前3位的依次为枣庄引种的红心菊、早小洋菊、滁菊。结合聚类分析结果,判定在原产地,滁州滁菊适于药用;在枣庄引种地,红心菊为优选的高产品种,早小洋菊为综合品质优良的品种。通过建立药用菊花品种产量和品质的综合评价体系,可为我国药茶两用菊花新品种的引种筛选和药食同源利用提供理论依据。

关键词：药用菊花综合评价主成分分析聚类分析

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我国鸡蛋价格波动规律和影响因素研究——基于PVAR模型和空间计量模型

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数学的实践与认识 2024年第9期54卷 52-69页

作者：于力超张雅琳任雪雁白雪菲中央民族大学理学院北京100081 中国联合网络通信集团有限公司山东省分公司、中国联通反诈中心山东济南250013 青岛工程职业学院基础课与思想政治课教学研究部山东青岛266000 唐山银行股份有限公司数据金融部河北唐山063006

随着我国农产品市场的快速发展,农产品的价格受到政府和居民越来越多的关注.作为我国"菜篮子工程"中的重要产品,准确把握鸡蛋价格的波动规律与影响因素对稳定禽肉市场具有重要意义.采用全国30个省份(除西藏、港澳台等地)2.12.1月至2.2.... 详细信息

随着我国农产品市场的快速发展,农产品的价格受到政府和居民越来越多的关注.作为我国"菜篮子工程"中的重要产品,准确把握鸡蛋价格的波动规律与影响因素对稳定禽肉市场具有重要意义.采用全国30个省份(除西藏、港澳台等地)2.12.1月至2.2.年3月的月度面板数据,探究鸡蛋价格的空间效应及蛋用雏鸡价格、玉米价格、居民消费价格指数、禽流感疫情、新冠疫情累计新增等因素对鸡蛋价格的影响.首先,通过分析我国鸡蛋价格变化曲线与空间分布图,研究我国鸡蛋价格的季节性和周期性波动特征及空间分布特征;然后通过构建面板向量自回归模型(PVAR模型),基于变量协整关系检验、格兰杰因果检验以及脉冲响应分析等非空间计量方法,得到影响鸡蛋价格变动的显著因素;最后,将空间因素纳入考虑范围之内,在证实鸡蛋价格具有空间自相关性的基础上,通过Hausman、LM等检验方法确定选用含有固定效应的空间误差面板模型,基于此得出成本因素是我国鸡蛋价格波动的主要原因.由此提出分季节引导市场方向、完善鸡蛋运输体系、加强政府监管和对重点地区进行宏观调控等稳定鸡蛋市场的建议.

关键词：鸡蛋价格面板数据 PVAR模型空间计量模型莫兰指数

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锥形双螺杆加工含能材料熔融过程数值模拟

塑料 2024年第1期53卷 163-171页

作者：岳梦岩张军李明娟宋秀铎薛平重庆化工职业学院重庆401228 西安近代化学研究所陕西西安710065 北京化工大学机电工程学院北京100029

螺杆挤出机是连续加工含能材料的一种重要设备,药料经过挤出机的加热和剪切作用能顺利熔融并进一步塑化。通过网格无关分析得出网格数量大于12.万后,GCI(网格收敛指数)小于3%且最大压力变化幅度较小,确定采用网格数为12.12.5的网格进行... 详细信息

螺杆挤出机是连续加工含能材料的一种重要设备,药料经过挤出机的加热和剪切作用能顺利熔融并进一步塑化。通过网格无关分析得出网格数量大于12.万后,GCI(网格收敛指数)小于3%且最大压力变化幅度较小,确定采用网格数为12.12.5的网格进行模拟。首次使用FLUENT中的Solidification&Melting模型对锥形双螺杆挤出机加工含能材料的熔融过程进行模拟,得到熔融段熔体分数、流动速度和温度等参数;基于质量守恒定律模拟分析锥形双螺杆挤出机中药料熔融过程的压力变化。在此基础上,通过改变螺杆转速、机筒温度和螺杆温度,分析了工艺参数对熔融过程的影响;通过改变螺杆的槽深、导程和法向螺棱宽度,分析螺杆结构对熔融过程的影响。

关键词：含能材料熔融锥形双螺杆工艺参数螺杆结构模拟

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大蒜加工废水处理研究进展

食品与发酵工业 2024年第1期50卷 359-364页

作者：张成明刘明源吴江涛张丽魏峰耿雅雯李砚飞董保成李十中薛忠财徐州生物工程职业技术学院徐州市生物制药与废弃物综合利用工程技术研究中心江苏徐州221006 南京伯恩哈德新能源研究院有限公司江苏南京211500 泰州职业技术学院药学院江苏泰州225300 安徽润景信息科技有限公司安徽芜湖241000 河北青县新能源技术推广中心河北沧州062650 农业农村部农业生态与资源保护总站北京100125 清华大学核能与新能源技术研究院中美生物燃料联合研究中心北京100084 河北民族师范学院资源与环境科学学院河北承德067000

我国是世界上最大的大蒜生产国和出口国,蒜片是主要的出口品种之一。每生产1 t蒜片会产生2. t以上的大蒜加工废水。大蒜加工废水具有强烈的杀菌作用,给其生物法处理带来了困难。文章围绕大蒜加工废水的特点和组成、大蒜素抑菌机理、大... 详细信息

我国是世界上最大的大蒜生产国和出口国,蒜片是主要的出口品种之一。每生产1 t蒜片会产生2. t以上的大蒜加工废水。大蒜加工废水具有强烈的杀菌作用,给其生物法处理带来了困难。文章围绕大蒜加工废水的特点和组成、大蒜素抑菌机理、大蒜加工废水的生物法处理、膜分离、高级氧化等工艺展开综述,以期为改进现有大蒜加工废水处理工艺提供借鉴。

关键词：蒜片大蒜加工废水抑菌活性微生物菌群生物法处理高级氧化

Identification of Molecular Markers for a Aphid Resistance Gene in Sorghum and Selective Efficiency Using These Markers

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Journal of Integrative Agriculture 2012年第7期11卷 1086-1092页

作者： CHANG Jin-hua CUI Jiang-hui xue Wei zhang Qing-wen college of Agriculture and Biotechnology China Agricultural University Beijing 100096 P.R.China college of Agriculture Agricultural University ofHebei Baoding 071001 P.R.China Student Employment Guidance Center Baoding Vocational and Technical College Baoding 071001 P.R.China

In this study, an F2.segregated population obtained by hybridization between the aphid-sensitive sorghum strain Qiansan and aphid-resistant cultivar Henong 16 was used to establish an aphid-resistant pool and an aphid-sensitive pool. 192.pairs of AFLP （amplified fragment length polymorphism） marker primers were screened in these pools using BSA （bulked segregant analysis）. Three pairs of EcoR I-CTG/Mse I-CCT, EcoR I-CTG/Mse I-CAT, and EcoR I-AGT/Mse I-CCC showed linkage with aphis resistance. EcoR I-CTG/Mse I-CCT-475, EcoR I-CTG/Mse I-CAT-390, and EcoR I-AGT/Mse I-CCC- 350 （E42.M52.350） were mapped within 6, 10, and 13 cM distances with the aphid-resistant gene by using Mapmaker 3.0 software. The bands amplified by EcoR I-CTG/Mse I-CCT-475 and EcoR I-CTG/Mse I-CAT-390 were extracted, cloned, and sequenced. Specific primers of SCAR （sequence characterized amplified regions） were then designed from these bands. A specific band of 300 bp was amplified by a pair of SCAR primers designed based on the sequence obtained from the EcoR I-CTG/Mse I-CAT-390 marker. The SCAR marker was named SCAS0. The marker was used to detect the F2. BC1, and F2.3 populations. The selective efficiency was 86.8, 91.1, and 86.3% in the BC1, F2. and F2.3 populations, respectively. The average selective efficiency was 88.2..

关键词： sorghum bicolor aphid resistance gene molecular marker SCAR molecular assistant selection

H9N2.型禽流感病毒HA基因的克隆及其DNA疫苗的动物免疫试验

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生物化学与生物物理进展 2004年第2期31卷 163-166页

作者：何宏轩秦曦明张强哲汤义刘丽艳郑昌学段明星清华大学生物科学与技术系生物膜与膜生物工程国家重点实验室北京100084 河南职业技术师范学院动物科学系新乡453003

血凝素 (HA)是决定禽流感病毒的毒力强弱和免疫原性的主要蛋白质 .根据已发表的H9亚型AIV的HA基因序列 ,设计合成了 1对H9HA特异引物 ,以AIVA/Chicken/Henan/ 1 / 1 999/ (H9N2.)核酸为模板 ,通过RT PCR扩增出 1条 1 6kbcDNA片段 .将H... 详细信息

血凝素 (HA)是决定禽流感病毒的毒力强弱和免疫原性的主要蛋白质 .根据已发表的H9亚型AIV的HA基因序列 ,设计合成了 1对H9HA特异引物 ,以AIVA/Chicken/Henan/ 1 / 1 999/ (H9N2.)核酸为模板 ,通过RT PCR扩增出 1条 1 6kbcDNA片段 .将HA基因插入pVAX1中 ,构建了真核表达质粒pVAX H9.采用活体电击法免疫 3周龄SPF鸡 1 0只 ,剂量为 5 0 μg/只 ,3周后加强免疫一次 ,5周后以 1 0 0倍鸡胚感染剂量 (EID)的HA基因同源病毒对所有鸡进行攻毒 .其间每周检测抗体水平变化 ,6周后以棉拭子进行泄殖腔病毒分离 .结果为攻毒后免疫组鸡HI效价为 9log2. 1 0log2.,对照组为 2.og2. 4log2.;免疫组病毒分离数为 0 / 1 0 ,对照组为 1 0 / 1 0 .

关键词：禽流感病毒血凝素基因 RT-PCR 克隆 DNA疫苗

Distinctive effects of CD34- and CD133-specific antibody-coated stents on re-endothelialization and in-stent restenosis at the early phase of vascular injury

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Regenerative Biomaterials 2015年第2期2卷 87-96页

作者： xue Wu tieying Yin Jie Tian Chaojun Tang Junli Huang Yinping Zhao Xiaojuan {2. Xiaoyan Deng Yubo Fan Donghong Yu Guixue Wang Key Laboratory of Biorheological Science and Technology(Chongqing University) Ministry of EducationChongqing Engineering Laboratory in Vascular ImplantsBioengineering CollegeChongqing UniversityNo.174 ShazhengjieShapingbaChongqing 400044China School of Biological Science and Medical Engineering Beihang UniversityNo.37 XueYuan RoadHaiDian DistrictBeijing 100191China Department of Biotechnology Chemistryand Environmental EngineeringAalborg UniversityFredrik Bajers Vej 7Building H9220AalborgDenmark

It is not clear what effects of CD34-and CD133-specific antibody-coated stents have on reendothelialization and in-stent restenosis(ISR)at the early phase of vascular *** study aims at determining the capabilities of different coatings on stents(***,anti-CD133 and anti-CD34 antibodies)to promote adhesion and proliferation of endothelial progenitor cells(EPCs).The in vitro study revealed that the adhesion force enabled the EPCs coated on glass slides to withstand flow-induced shear stress,so that allowing for the growth of the cells on the slides for 48 *** in vivo experiment using a rabbit model in which the coated stents with different substrates were implanted showed that anti-CD34 and anti-CD133 antibody-coated stents markedly reduced the intima area and restenosis than bare mental stents(BMS)and gelatin-coated *** with the anti-CD34 antibody-coated stents,the time of cells adhesion was longer and earlier present in the anti-CD133 antibody-coated stents and anti-CD133 antibody-coated stents have superiority in re-endothelialization and inhibition of *** conclusion,this study demonstrated that anti-CD133 antibody as a stent coating for capturing EPCs is better than anti-CD34 antibody in promoting endothelialization and reducing ISR.

关键词： stent CD133 CD34 endothelial progenitor cells re-endothelialization

Role of the rhizosphere of a flooding-tolerant herb in promoting mercury methylation in water-level fluctuation zones

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Journal of Environmental Sciences 2022年第9期34卷 139-151页

作者： Juan Wang Yuping Xiang Xiaosong Tian Cheng zhang Guiqing Gong Jinping xue Tao Jiang Dingyong Wang Yongmin Wang Interdisciplinary Research Center for Agriculture Green Development in yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China Laboratory of Environmental Nanotechnology&Health Effect Chinese Academy of SciencesResearch Center for Eco-Environmental SciencesBeijing 100085China college of Resources and Safety Chongqing Vocational Institute of EngineeringChongqing 402260China Institut des Sciences Analytiques et des Physico-Chimie pour l’Environnement et les Materiaux(IPREM) UMR 5254CNRSUniversitede Pau et des Pays de l’AdourPau 64000France

The water-level fluctuation zone(WLFZ) has been considered as a hotspot for mercury(Hg) methylation. Flooding-tolerant herbs are gradually acclimated to this water-land ecotone, tending to form substantial root systems for improving erosion resistance. Accompanying rhizosphere microzone plays crucial but unclear roles in methylmercury(Me Hg) formation in the WLFZ. Thus, we conducted this study in the WLFZ of the Three Gorges Reservoir, to explore effects of the rhizosphere of a dominant flooding-tolerant herb(bermudagrass) on Me Hg production. The elevated Hg and Me Hg in rhizosphere soils suggest that the rhizosphere environment provides favorable conditions for Hg accumulation and methylation. The increased bioavailable Hg and microbial activity in the rhizosphere probably serve as important factors driving Me Hg formation in the presence of bermudagrass. Simultaneously, the rhizosphere environments changed the richness, diversity, and distribution of hgc A-containing microorganisms. Here, a typical ironreducing bacterium( Geobacteraceae) has been screened, however, the majority of hgc A genes detected in rhizosphere, near-, and non-rhizosphere soils of the WLFZ were unclassified. Collectively, these results provide new insights into the elevated Me Hg production as related to microbial processes in the rhizosphere of perennial herbs in the WLFZ, with general implications for Hg cycling in other ecosystems with water-level fluctuations.

关键词： Three Gorges Reservoir Water-level fluctuation zone Rhizosphere soil Methylmercury Mercury methylator