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海南省2015—2021年乙型肝炎流行病学特征分析及趋势预测

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中国热带医学 2024年第2期24卷 143-149页

作者：符振旺范世恒李卫霞海南省疾病预防控制中心传染病预防控制所海南海口570203 海南医学院公共卫生与全健康国际学院海南海口571199

目的分析海南省2015—2021年乙型肝炎(简称“乙肝”)的流行病学特征,预测不同人群乙肝发病趋势,基于流行特征及预测结果为乙肝防治工作提供科学依据。方法对海南省乙肝发病的流行病学特征进行描述性分析,基于灰色预测模型及多项式模型... 详细信息

目的分析海南省2015—2021年乙型肝炎(简称“乙肝”)的流行病学特征,预测不同人群乙肝发病趋势,基于流行特征及预测结果为乙肝防治工作提供科学依据。方法对海南省乙肝发病的流行病学特征进行描述性分析,基于灰色预测模型及多项式模型研究海南不同人群乙肝报告发病率规律,采用平均相对误差绝对值最小原则选择最佳模型,并预测未来发病率。结果海南省2015—2019年乙肝报告发病率呈逐年上升的趋势,2020年起出现了下降趋势,2017—2021年报告发病率在0~<15岁和15~<30岁年龄组均呈现下降趋势,60~<75岁和≥75岁年龄组发病率基本趋于平稳。30~<45岁和45~<60岁人群年均发病数、每年发病率均较高。乙肝年均报告发病率男女性别比约为2∶1。各职业中乙肝发病数以农民为主且年均占比为43.06%。乙肝报告年发病数存在地区差异性分布,其中5个市县逐年下降、1个市县先上升后下降,2个市县保持稳定,其他市县存在逐年上升的趋势。2022—2024年的发病率预测值分别为127.43/10万、116.05/10万和102.09/10万。结论近年来,海南省30岁以下人群的乙肝发病呈现了递减趋势,说明海南乙肝疫苗纳入儿童免疫规划等防控策略产生较好效果,需要重点加强对高发病率年龄组及高发性别的防治工作。不同地区乙肝发病存在差异,提示要继续加强存在逐年递增趋势地区的乙肝防控知识健康宣讲、筛查治疗和疫苗免疫接种等综合防控措施。

关键词：乙型肝炎海南省流行病学特征多项式模型灰色预测模型

液相色谱-离子色谱联用体系同时测定环境基质中的6种硝基芳烃类化合物和3种阴离子

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色谱 2024年第1期42卷 92-98页

作者：雷佳诚郑黄荣刘璐李巍霞中国计量大学标准化学院浙江杭州310018 中国标准化协会北京100037

同时测定环境土壤和水基质中的硝基芳烃类化合物和阴离子对于选择合适的硝基芳烃类化合物降解方法和实现地表水水质监测具有重要意义。本文通过两个六通阀和一根富集柱将高效液相色谱和离子色谱连接,搭建了色谱联用体系。系统操作可分为... 详细信息

同时测定环境土壤和水基质中的硝基芳烃类化合物和阴离子对于选择合适的硝基芳烃类化合物降解方法和实现地表水水质监测具有重要意义。本文通过两个六通阀和一根富集柱将高效液相色谱和离子色谱连接,搭建了色谱联用体系。系统操作可分为4个阶段:(A)样品加载到定量环;(B)分离硝基芳烃类化合物和阴离子;(C)阴离子在AG20柱中富集;(D)高效液相色谱和离子色谱分别测定硝基芳烃类化合物和阴离子。通过将液相色谱柱直接连接电导率检测器,确定阴离子流出液相色谱柱的时间,优化六通阀的切换时间,保证方法的准确性。在最优条件下,阴离子的检出限为0.005~0.020 mg/L,硝基芳烃类化合物的检出限为0.043~0.150 mg/L。3组不同加标浓度样品的平均回收率为88.20%~105.38%,相对标准偏差为2.0%~11.5%。该方法被用于检测5份地表水样品和5份土壤样品,硝基芳烃类化合物均未检出,3种阴离子在地表水样品中的检出量为0.41~55.3 mg/L,在土壤样品中的检出量为0.56~30.2 mg/kg。经过方法学验证和实际样品检测,证明该色谱联用体系检测方法自动化程度高,操作简单,重复性好,准确度高,具有广泛的适用性和较高的灵敏度,适用于环境基质中硝基芳烃类有机物和亚硝酸根离子等阴离子含量的快速测定。

关键词：离子色谱高效液相色谱硝基芳烃类化合物阴离子土壤环境水

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社会学视角下开放大学提升老年教育质量研究

山西开放大学学报 2024年第2期29卷 11-14页

作者：李伟霞山西开放大学山西太原030027

老年教育是终身教育的最后阶段,也是老年人继续社会化的重要途径,能够进一步满足老年群体自我价值实现的需要。新时代背景下,开放大学要进一步发挥体系办学优势,丰富老年教育内涵,创新老年教育形式,帮助更多老年人通过教育改变传统的老... 详细信息

老年教育是终身教育的最后阶段,也是老年人继续社会化的重要途径,能够进一步满足老年群体自我价值实现的需要。新时代背景下,开放大学要进一步发挥体系办学优势,丰富老年教育内涵,创新老年教育形式,帮助更多老年人通过教育改变传统的老年观,进而提升生活品质,为社会发展继续贡献力量。

关键词：社会学视角开放大学老年教育

The number of simple modules of a cellular algebra

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Science China Mathematics 2005年第6期48卷 735-745页

作者： li weixia XI Changchang School of Mathematical Sciences Beijing Normal University 100875 Beijing China School of Mathematical Sciences Beijing Normal University 100875 Beijing China

Let n be a natural number, and let A be an indecomposable cellular algebra such that the spectrum of its Cartan matrix C is of theform {n, 1,..., 1}. In general, not every natural number could be the number of non-isomorphic simple modules over such a cellular algebra. Thus, two natural questions arise: (1) which numbers could be the number of non-isomorphic simple modules over such a cellular algebra A ? (2) Given such a number, is there a cellular algebra such that its Cartan matrix has the desired property ? In this paper, we shall completely answer the first question, and give a partial answer to the second question by constructing cellular algebras with the pre-described Cartan matrix.

关键词： simple module, cellular algebra, Cartan matrix, spectrum.

Weight distribution of Preparata codes over Z_4 and the construction of 3-designs

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Science China Mathematics 2014年第6期57卷 1155-1162页

作者： li weixia SHEN Hao School of Mathematical Sciences Qingdao University Department of Mathematics Shanghai Jiao Tong University

In this paper,we calculate the number of the codewords(with Hamming weight 7)of each type in the Preparata codes over Z4,then give the parameter sets of 3-designs constructed from the supports of the codewords of each ***,we prove that the first two families of 3-designs are simple and the third family of the 3-designs has repeated blocks.

关键词： t-designs weight distribution Preparata codes over Z4

Safety Analysis of the Eco-Approach and Departure Application at a Signalized Corridor

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Tsinghua Science and Technology 2018年第2期23卷 157-171页

作者： weixia li Guoyuan Wu Yi Zhang Matthew J. Barth Department of Automation Tsinghua University Beijing 100084 China. Bourns College of Engineering-Center for Environmental Research and Technology (CE-CERT) University of California Riverside CA 92507 USA.

Various intelligent transportation systems and strategies for reducing vehicle fuel consumption and emissions have been developed. Energy and emissions could be reduced with the compromise of travel time in some environment-focused Connected Vehicle(CV) applications, which highlighted performance measures in terms of mobility and sustainability. Nevertheless, few studies have focused on safety assessment of such CV applications. In this study, a CV-based eco-driving application, namely, Eco-Approach and Departure(EAD), is selected as an example. A microscopic safety analysis tool, Surrogate Safety Assessment Model(SSAM), is utilized to assess the safety influence of EAD application in multiple scenarios. Further analysis is performed from two perspectives:(1) application users, i.e., EAD-equipped vehicles versus unequipped vehicles; and(2) traffic operators, i.e., overall traffic performance with and without the introduction of EAD. For each perspective, conflict statistics(e.g., frequency, time-to-collision distribution), overall and by type, are analyzed. Results indicate EAD is beneficial in improving the safety performance of equipped vehicles. The influence of EAD on overall traffic is scenario dependent, and a high penetration rate shows positive effects on network-wide safety benefits for most scenarios.

关键词： Eco-Approach and Departure(EAD) Surrogate Safety Assessment Model(SSAM) safety analysis conflict type Time-To-Collision(TTC)

MicroRNA encoded by the HSV-1 latency-associated transcript anti-apoptotic function in human mesenchymal stem cells

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Chinese Science Bulletin 2008年第11期53卷 1691-1698页

作者： ZHANG Jing li YongMei DU WenCai li GuangMing li weixia ZHU Ze Department of Medical Microbiolgy Tianjin Key Laboratory of Cellular and Molecular Immunology '13anjin Medical University Tianjin300070 China

Human mesenchymal stem cells (HMSCs) have emerged as a promising cell type for tissue repopulat-ing and for use as ex vivo gene delivery vehicles. Herpes simplex virus-1 (HSV-1) possesses many vector features, which make it especially suitable for HMSC applications. Here we performed real-time RT-PCR to detect the level of mature microRNA encoded by the HSV-1 latency-associated transcript (microRNA-LAT) in HMSCs cytoplasm with a specific stem loop reverse primer. Three small interfering RNAs (siRNAs) were chemically synthesized towards microRNA-LAT, TGF-β1 and SMAD3. The results demonstrate that HSV-1 and microRNA-LAT prevented HMSCs from undergoing cisplatin-induced apoptosis. In comparison with cells only treated with cisplatin, the apoptosis phenomenon with HSV-1 and microRNA-LAT were markedly reduced. The apoptosis rates of these two groups were both lower (Pling pathway components were by these means knocked down. Moreover, the levels of the mature microRNA-LAT were decreased in cis-platin-treated HMSCs. In conclusion, HSV-1 and microRNA-LAT exert their anti-apoptotic effect on HMSCs by down-regulation of the TGF-β signalling pathway. Thus HSV-1, having anti-apoptotic effect naturally encoded in its microRNA-LAT, is a good candidate to be developed for HMSC vector.

关键词：间叶细胞干细胞组织再生单纯疱疹病毒1 基因转录

基于磁珠配体垂钓和液相色谱-质谱联用技术的威廉环毛蚓抗血栓大分子活性成分研究

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中草药 2024年第13期55卷 4318-4326页

作者：吴娅丽韩冰李伟霞王晓艳张明亮张辉杨柳青唐进法河南中医药大学第一附属医院药学部河南郑州450003 河南省中药临床应用、评价与转化工程研究中心、河南省中药临床药学中医药重点实验室、河南省中药安全评价与风险防控工程研究中心河南郑州450003 河南中医药大学药学院河南郑州450046

目的通过构建靶蛋白固定化磁珠,从威廉环毛蚓Pheretima guillemi中垂钓出与靶蛋白(纤维蛋白原、纤溶酶原)直接作用的抗血栓活性大分子成分,并经液相色谱-质谱联用(LC-MS/MS)技术鉴定。方法优化并合成纤维蛋白原、纤溶酶原固定化羧基磁珠... 详细信息

目的通过构建靶蛋白固定化磁珠,从威廉环毛蚓Pheretima guillemi中垂钓出与靶蛋白(纤维蛋白原、纤溶酶原)直接作用的抗血栓活性大分子成分,并经液相色谱-质谱联用(LC-MS/MS)技术鉴定。方法优化并合成纤维蛋白原、纤溶酶原固定化羧基磁珠,分别通过固定化量、透射电镜、傅里叶红外光谱仪、激光纳米粒度分析仪表征功能化磁珠的靶蛋白固定量、微观形态、官能团及表面带电性;利用功能化磁珠从威廉环毛蚓抗血栓部位DPf3中垂钓与靶蛋白直接作用的抗血栓大分子活性成分,洗脱后经LC-MS/MS技术分析,并结合威廉环毛蚓物种蛋白质数据库比对鉴定。结果靶蛋白固定化磁珠的最佳制备方案为将纤维蛋白原(0.4 mg/mL)或纤溶酶原(1 mg/mL)与磁珠于4℃混旋孵育8 h,纤维蛋白原和纤溶酶原的最大偶联量分别为(9.84±2.17)μg/mg和(7.24±0.91)μg/mg;经表征,靶蛋白均已成功固定于磁珠表面。DPf3经纤维蛋白原、纤溶酶原固定化磁珠垂钓所得洗脱液经扫描比对,分别鉴定到20种和27种蛋白质,多属于丝氨酸蛋白酶类成分。结论通过磁珠配体垂钓策略和LC-MS/MS技术可从威廉环毛蚓中快速筛选和鉴定目标生物活性大分子,可为动物类中药大分子的分离鉴定提供参考。

关键词：威廉环毛蚓抗血栓大分子成分磁珠配体垂钓纤维蛋白原固定化磁珠纤溶酶原固定化磁珠

The Signless Dirichlet Spectral Radius of Unicyclic Graphs

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Journal of Mathematical Research with Applications 2017年第3期37卷 262-266页

作者： Guangjun ZHANG weixia li School of Mathematics and Physics Qingdao University of Science and Technology School of Mathematics and Statistics Qingdao University

Let G be a simple connected graph with pendant vertex set ?V and nonpendant vertex set V;. The signless Laplacian matrix of G is denoted by Q（G）. The signless Dirichlet eigenvalue is a real number λ such that there exists a function f ≠ 0 on V（G） such that Q（G）f（u） = λf（u） for u ∈ V;and f（u） = 0 for u ∈ ?V. The signless Dirichlet spectral radiusλ（G） is the largest signless Dirichlet eigenvalue. In this paper, the unicyclic graphs with the largest signless Dirichlet spectral radius among all unicyclic graphs with a given degree sequence are characterized.

关键词： signless Dirichlet spectral radius unicyclic graph degree sequence