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考虑非平稳因素的大件车与普通车流混行中小跨径桥梁安全评估

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中国公路学报 2024年第8期37卷 111-124页

作者：刘博韩万水赵卫华王涛刘修平王俊峰袁阳光长安大学公路学院广东省交通运输厅公路路政处西安建筑科技大学土木工程学院

为满足大件运输车辆与普通车流混合通行中小跨径桥梁安全评估的紧迫需求，提出了基于分项系数模式的混行车流通行桥梁可靠度评估方法。首先，输入考虑空间相关的路面不平整度，建立混行车流-桥梁耦合振动分析系统；其次，根据WIM系统实... 详细信息

为满足大件运输车辆与普通车流混合通行中小跨径桥梁安全评估的紧迫需求，提出了基于分项系数模式的混行车流通行桥梁可靠度评估方法。首先，输入考虑空间相关的路面不平整度，建立混行车流-桥梁耦合振动分析系统；其次，根据WIM系统实测车流数据，综合考虑分车道荷载差异与车辆特征参数相关性模拟普通车流荷载，在极值理论框架下将非平稳车载过程离散化建立混行车流极值模型；然后，基于可靠度理论开展对评估基准期、目标可靠指标及分项系数校准问题的研究，并确定了抗力非平稳退化模型；最后，采用构建的评估方法对工程实例开展应用分析。结果表明：混行车流相比大件车单车居中过桥的结构响应增幅可达到30%以上；普通车流模拟结果中重载货车的轴重、轴距分布均匀，与实际车流的分布特征基本相符；基于历史交通量确定的Logistic函数可较好地描述交通量非平稳增长规律；单次混行车流通行桥梁的目标可靠指标受混行车流年均通行次数的影响，呈现增长放缓的趋势；基于Gamma随机过程的抗力非平稳退化模型与连续不间断的退化进程相适应；通过对实例桥梁的安全评估，经校准后的分项系数对交通量增长不敏感，抗力退化相比交通量增长对混行车流通行安全的影响更为显著，综合考虑二者非平稳因素对结构安全评估尤为重要。所建立的评估方法可为大件运输车辆与普通车流混行中小跨径桥梁的安全评估提供参考。

关键词：桥梁工程中小跨径桥梁可靠度评估混行车流车-桥耦合振动非平稳因素

结直肠癌患者KDM6A蛋白表达与基因突变及错配修复的关系

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诊断病理学杂志 2024年第3期31卷 203-207页

作者：武景波刘慧李小静刘秀萍复旦大学附属上海市第五人民医院病理科上海200240

目的探讨结直肠癌(CRC)组织中KDM6A蛋白表达与KRAS/NRAS/BRAF/PIK3CA基因突变及DNA错配修复(MMR)的关系。方法收集111例手术切除CRC患者的标本,通过免疫组织化学检测KDM6A蛋白及DNA错配修复相关蛋白(MLH1、MSH2、MSH6和PMS2)表达,通过... 详细信息

目的探讨结直肠癌(CRC)组织中KDM6A蛋白表达与KRAS/NRAS/BRAF/PIK3CA基因突变及DNA错配修复(MMR)的关系。方法收集111例手术切除CRC患者的标本,通过免疫组织化学检测KDM6A蛋白及DNA错配修复相关蛋白(MLH1、MSH2、MSH6和PMS2)表达,通过扩增阻碍突变系统(ARMS)法检测KRAS/NRAS/BRAF/PIK3CA基因突变,通过统计学分析KDM6A蛋白表达与KRAS/NRAS/BRAF/PIK3CA基因突变、MMR及临床病理特征、预后关系,并通过TCGA数据库CRC数据对预后进行验证分析。结果KDM6A表达率在基因突变CRC患者中显著升高,KDM6A表达患者多为错配修复完整(pMMR)(P<0.05)。有脉管侵犯CRC患者的KDM6A表达率显著高于无脉管侵犯者(P<0.05)。KDM6A阳性组和阴性组CRC患者总生存期(OS)差异无统计学意义(P=0.470)。结论CRC患者中KDM6A表达与KRAS/NRAS/BRAF/PIK3C基因突变有关,更常见于pMMR患者,更易发生于有脉管侵犯患者,但与患者预后无关。

关键词：结直肠癌 KDM6A 基因突变错配修复预后

外周血PLR、Fib水平对老年COPD患者急性加重及病情程度的评估价值

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现代生物医学进展 2024年第12期24卷 2337-2340页

作者：夏洪梅刘秀平薛小花刘善红董志萍淄博市第一医院老年医学科山东淄博255200 淄博市第一医院临床药学科山东淄博255200 淄博市第一医院心内二科山东淄博255200

目的:探讨外周血血小板/淋巴细胞比值(platelet-to-lymphocyte ratio,PLR)、纤维蛋白原(fibrinogen,Fib)水平对老年慢性阻塞性肺疾病急性加重(acute exacerbation of chronic obstructive pulmonary disease,AECOPD)及病情程度的评估价值。方法:选取2020年1月至2022年12月期间我院呼吸与危重症医学科收治的老年AECOPD患者40例作为AECOPD组,根据病情程度将其分为Ⅰ级(n=9)、Ⅱ级(n=17)、Ⅲ级(n=14)。选取同期在我院门诊复诊的老年慢性阻塞性肺疾病稳定期(stable chronic obstructive pulmonary disease, SCOPD)患者40例作为SCOPD组。比较各组一般资料及PLR、Fib水平。采用logistic回归模型分析老年AECOPD的独立危险因素,通过受试者工作特征曲线(receiver operating characteristic curve, ROC)评估PLR、Fib对老年AECOPD的预测价值。结果:AECOPD组外周血PLR、Fib水平均高于SCOPD组(P<0.05);老年AECOPD不同临床分级患者PLR、Fib水平比较,差异有统计学意义(P<0.05),Ⅲ级最高,其次是Ⅱ级,Ⅰ级最低;Logistic回归分析显示,PLR、Fib的比值比分别为1.857、2.094,是老年AECOPD的独立危险因素(P<0.05);ROC曲线分析显示,PLR、Fib及二者联合预测老年AECOPD的曲线下面积分别为0.862、0.853、0.948,以二者联合预测价值最高(敏感度为87.50%,特异度为95.00%)。结论:外周血PLR、Fib水平与老年AECOPD患者病情程度相关,二者联合对老年AECOPD的诊断价值最高。

关键词：慢性阻塞性肺疾病急性加重血小板/淋巴细胞比值纤维蛋白原诊断

Effects of rock fragments on yak dung greenhouse gas emissions on the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2016年第11期13卷 2006-2014页

作者： DU Zi-yin WANG Xiao-dan liu xiu-ping CAI Yan-jiang Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Center for Agricultural Resources Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China

Dung deposition is an important pathway of nutrient return and redistribution in alpine grasslands of the Qinghai-Tibetan *** date,information on the greenhouse gas emissions of yak dung on alpine grasslands,especially where there are large amounts of rock fragments,is *** aim,therefore,was to evaluate variations in N_2O,CH_4,and CO_2 emissions from yak dung(CCD),and compare it to dung placed on rock fragments(RCD),alpine steppe soil(CSD),and a soil and rock fragment mixture(RSD) over a 30-day incubation *** results showed that the total N_2O emissions from treatments without soil were significantly(P < 0.05) lower than those from treatments with *** highest total CH_4 emissions were detected in the CSD treatment,while CH_4 losses from treatments without rock fragments were significantly(P < 0.05) greater than those with rock *** total CO_2 emissions from the RSD treatment was 6.30%–12.0% lower than those in the other three *** soil beneath yak dung pats elevated the globalwarming potential(GWP),while the addition of rock fragments to the soil significantly(P < 0.05) decreased the GWP by reducing emissions of the three greenhouse *** therefore suggest that interactions between rock fragments and alpine steppe soil are effective in decreasing yak dung greenhouse gas *** finding indicates that rock fragments are an effective medium for reducing greenhouse gas emissions from dung pats,and more attention should therefore be paid to evaluate its ecological impact in future *** results should help guide scientific assessments of regional GHG budgets in agricultural ecosystems where the addition of livestock manure to soils with large amounts of rock fragments is common.

关键词： Rock fragments Yak dung Nitrous oxide Methane Qinghai-Tibetan Plateau

Organic skeleton correspondence using part arrangements

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Applied Mathematics(A Journal of Chinese Universities) 2019年第3期34卷 326-339页

作者： LI Shu-hua liu xiu-ping CAO Jun-jie WANG Shi-yao School of Mathematical Sciences Dalian University of Technology

Shape correspondence between semantically similar organic shapes with large shape variations is a difficult problem in shape *** part geometries are no longer similar,we claim that the challenge is to extract and compare prominent shape substructures,which are recurring part arrangements among semantically related *** main premise is that the challenge can be solved more efficiently on curve skeleton graphs of shapes,which provide a concise abstraction of shape geometry and *** of directly searching exponentially many skeleton subgraphs,our method extracts the intrinsic reflectional symmetry axis of the skeleton to guide the generation of subgraphs as part *** any two subgraphs from two skeletons,their orientations are aligned and their pose variations are normalized for ***,the matchings of all subgraph pairs are evaluated and accumulated to the skeletal feature node *** comparison results with the state-of-the-art work show that our method significantly improves the efficiency and accuracy of the semantic correspondence between a variety of shapes.

关键词： shape correspondence skeleton symmetry axis shape substructure

Carbon sequestration of plantation in Beijing-Tianjin sand source areas

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Journal of Mountain Science 2018年第10期15卷 2148-2158页

作者： liu xiu-ping ZHANG Wan-jun CAO Jian-sheng YANG Bai CAI Yan-jiang Key Laboratory of Agricultural Water Resources Hebei Key Laboratory of Agricultural Water-Saving Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Environmental Sciences Division Oak Ridge National Laboratory Key Laboratory of Mountain Environment Evolvement and Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust hazards. The carbon sequestration dynamics can be used to assess the ecological effects of an ecological restoration project. Here, we conducted vegetation and soil study to assess the carbon sequestration in the plantations with 10 years old stands in Beijing-Tianjin sand source areas. The results at the site scales indicated that the average net increase of plantation ecosystem carbon stock was 33.8 Mg C ha^(-1), with an annual increase rate of 3.38 Mg C ha^(-1) yr^(-1). The average net increase of carbon varied among regions, vegetation types, and forest management activities. Soil bulk density in the top soil decreased slightly after 10-year implementation of the project. Coniferous forests and shrubs are suitable plant species for sand source *** restoration in the plantations is a practical and feasible and promising approach for enhancing ecosystem carbon sequestration potential.

关键词： Afforestation Carbon sequestration Carbon density Forest management Restoration Sand source control

Auxiliary Ligand Oriented CdⅡ-flexible Dicarboxylic Acid Coordination Frameworks:Syntheses, Structures and Properties

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1311-1319页

作者： CHEN Yong-Qiang ZHAI Jia-Xin TIAN Yuan liu xiu-ping College of Chemistry and Chemical Engineering Jinzhong UniversityYuciShanxi 030600China

Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(L1 = 3,3’-[1,3-benzenebis(carbonylimino)]bi(benzoate), L2 = 1,3-bi(4-pyridyl)propane, L3 = 4,4’-bipyridine). Complex 1 crystallizes in triclinic, space group P■ with a = 8.7415(5), b = 12.2247(7), c =16.2415(10) ?, β = 95.6790(10)°, V = 1525.11(16) ?3, Dc = 1.553 mg·m-3, C35H28CdN4O6, Mr = 713.02, F(000) = 724, μ(MoKα) = 0.770 mm–1, Z = 2, R/wR(I > 2σ(I))a = 0.0302/0.0773. However, complex 2 crystallizes in monoclinic, space group P21/n with a = 11.4986(7), b = 23.0911(14), c = 11.9943(8) ?, β = 115.9500(10)°, V = 2863.6(3) ?3, Dc = 1.598 mg·m-3, C32H24CdN4O7, Mr = 688.96, F(000) = 1392, μ(MoKα) = 0.820 mm–1, Z = 4, R/wR(I > 2σ(I))a = 0.0283/0.0631. The structures of two complexes were characterized. Complexes 1 and 2 have different one-dimensional(1D) chain structures. In addition, we have also made a preliminary study on the properties of the two complexes.

关键词： coordination framework auxiliary ligand structure property

顺义滨河森林公园林内小气候及人体舒适度效应分析

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科学技术与工程 2024年第17期24卷 7066-7072页

作者：律江李新宇段敏杰孟祥雪刘京宇赵英波闫琛玮刘秀萍北京市共青林场北京101399 北京市园林绿化科学研究院北京100102 园林绿地生态功能评价与调控技术北京市重点实验室北京100102 北京城市生态系统定位监测研究站北京100102

为探究城市绿地调节小气候、缓解城市热岛作用,以顺义滨河森林公园绿地为对象,选择硬质铺装为对照,于2022年3—11月,对不同植物群落空气温度、相对湿度、风速进行实地监测,研究不同植物群落间小气候及人体舒适度的改善提升效应。结果表... 详细信息

为探究城市绿地调节小气候、缓解城市热岛作用,以顺义滨河森林公园绿地为对象,选择硬质铺装为对照,于2022年3—11月,对不同植物群落空气温度、相对湿度、风速进行实地监测,研究不同植物群落间小气候及人体舒适度的改善提升效应。结果表明:春季降温效果最好(2.74℃),其次是夏季(2.05℃),一天内在14:00前时段降温效果最为显著;夏季增湿效果最高(6.88%),其次是秋季(5.62%);在减弱风速效果中春季幅度最高(0.2 m/s),其次是夏季(0.07 m/s),上午时间段内减弱风速程度较大。春夏秋三季均能不同程度提高人体舒适度,其中夏季最高(1.54),其次是春季(0.54),夏季全天及春季、秋季的12:00—14:00可为人们提供一个较为舒适的环境。可见植物群落优化提升对于提高城市绿地生态效益发挥、改善城市生态环境均有着重要的作用,研究结果可为城市绿地植物群落结构优化提升、经营管理及市民休闲出行供借鉴参考。

关键词：城市绿地顺义滨河森林公园植物群落小气候人体舒适度

STUDY OF KINETIC ANALYTICAL METHOD BASED ON CATALYTIC REACTIONS

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晋中学院学报 1998年第1期21卷 6-7页

作者： liu xiu ping

In this thesis a reviwe is presented for the advances of catalytic spec trophotometric method, three new catalytic reaction systems were presented, and its rela live catalytic spectrophotometric methods have been established by flow injection tech nique. Particulary the relative chemometric methods and theories were used in the field of kinetic - catalytic analysis, in order to solve the problems of multicomponents analysis.

关键词： kinetic - catalytic spectrophotometric method flow injection analysis.