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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1072-1084页

作者： xuwei wang Yeshuang Xu State Key Laboratory of Ocean Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

The boundary condition is a crucial factor affecting the permeability variation due to *** experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss *** samples are filled into seven soil storerooms connected in *** evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are *** the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated *** the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage *** relationship between ΔR_(f) and Ci is different with the boundary *** exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test.

关键词： Suffusion Permeability Experimental investigation Boundary effect Horizontal seepage

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中国民航客运发展对入境旅游影响的空间效应——基于省域数据的空间计量分析

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云南地理环境研究 2024年第1期36卷 38-45页

作者：王旭伟谢童平江西师范大学管理科学与工程研究中心江西南昌330022 共青科技职业学院经济与管理学院江西九江332020

推动民航客运与入境旅游融合发展对加快中国入境旅游复苏具有重要意义。基于2008—2019年中国31个省域的面板数据,运用全局莫兰指数分析了入境旅游发展的空间自相关特征,运用空间面板杜宾模型分析了民航客运发展对入境旅游影响的空间效... 详细信息

推动民航客运与入境旅游融合发展对加快中国入境旅游复苏具有重要意义。基于2008—2019年中国31个省域的面板数据,运用全局莫兰指数分析了入境旅游发展的空间自相关特征,运用空间面板杜宾模型分析了民航客运发展对入境旅游影响的空间效应。研究表明:(1)中国省域入境旅游发展呈现显著的空间正相关特征,即入境旅游发展水平较高的省域在空间上集聚,入境旅游发展水平较低的省域在空间上集聚,但这种空间集聚特征具有弱化的趋势。(2)民航客运对中国入境旅游发展具有重要影响。在其他因素不变的条件下,民航客运发展水平提升1%,本省域的入境旅游规模会扩大0.22%,相邻省域的入境旅游规模会减少0.25%。(3)中国省域入境旅游发展对公路通达水平、对外开放水平、旅行社接待能力、空气污染程度较为敏感,而对高铁发展水平、旅游资源禀赋、酒店服务水平不敏感。要以推动民航客运高质量发展为着力点,提升入境旅游竞争力。要以全面深化民航客运合作为纽带,优化中国入境旅游发展格局。

关键词：民航客运入境旅游高铁空间面板杜宾模型空间效应

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Logistic回归法和机器学习算法构建子痫前期预测模型的比较

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中华围产医学杂志 2024年第7期27卷 572-581页

作者：许兴能陈胜柱周嘉怡杨思王旭薇余波澜广州医科大学附属第三医院妇产科广州510150 广东省产科重大疾病重点实验室(广东省妇产疾病临床医学研究中心、粤港澳母胎医学高校联合实验室) 广州510150 广州医科大学附属第三医院生物样本库广州510150

目的利用医院电子病历系统首页信息和临床检验数据通过logistic回归(logistic regression,LR)法和机器学习算法构建子痫前期(preeclampsia,PE)预测模型,同时比较机器学习算法和LR构建模型的预测性能。方法基于2012年1月1日至2019年12月3... 详细信息

目的利用医院电子病历系统首页信息和临床检验数据通过logistic回归(logistic regression,LR)法和机器学习算法构建子痫前期(preeclampsia,PE)预测模型,同时比较机器学习算法和LR构建模型的预测性能。方法基于2012年1月1日至2019年12月31日在广州医科大学附属第三医院就诊孕产妇的围产期数据和柔济妊娠检验数据库信息,根据临床诊疗指南和相关文献报道关联整合后选取数据量较为完整的孕24~28周共2736例孕妇的28项临床相关指标作为PE预测模型构建数据。将其中PE患者作为PE组(n=245),其余非PE患者中采用欠采样法选择255例为对照组。使用随机森林算法(random forest,RF)及极端梯度上升算法(eXtreme Gradient Boosting,XGB)和LR模型分别构建PE疾病预测模型。模型构建完成后,在2019年6月至2022年12月开展的PE前瞻性队列研究获得数据中(PE组38例,对照组80例),进行PE预测准确性的外部验证。采用准确度、灵敏度、特异度、受试者工作特征曲线下面积比较不同模型的预测效能。结果3种预测模型构建时纳入的指标提示,尿酸、肌酐、年龄、孕早期体重指数、尿素、甘油三酯、红细胞计数、嗜酸性粒细胞计数、总胆固醇、中性粒细胞计数、尿蛋白、丙氨酸氨基转移酶以及尿潜血是影响PE预测模型的指标。RF、XGB和LR模型在训练集和测试集中的受试者工作特征曲线下面积分别为0.851(95%CI:0.730~0.891)、0.955(95%CI:0.865~0.987)、0.884(95%CI:0.767~0.923)和0.845(95%CI:0.723~0.868)、0.907(95%CI:0.791~0.919)、0.851(95%CI:0.755~0.893)。在测试集中,RF、XGB和LR模型的准确度、灵敏度与特异度分别为0.803、0.607、0.958,0.864、0.790、0.927和0.832、0.661、0.971。在外部验证集中RF、XGB和LR预测模型的准确度分别为0.822、0.814和0.763;灵敏度分别为0.737、0.789和0.605;特异度分别为0.863、0.825和0.838,其中XGB模型的约登指数最高,为0.614。结论相对于传统的建模方法,利用机器学习算法可以在真实临床检测数据中建立更加有效的PE预测模型。

关键词：子痫前期预测模型 Logistic回归模型随机森林算法极端梯度上升算法

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Kinetic Analysis of Vectored Electric Propulsion System for Stratosphere Airship

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第5期33卷 559-565页

作者： Nie Ying Zhou Jianghua Yang Yanchu wang Sheng wang xuwei Academy of Opto-electronics Chinese Academy of Sciences Beijing 100094 P. R. China University of Chinese Academy of Sciences Beijing 100094 P.R. China

To enhance the controllability of stratosphere airship,a vectored electric propulsion system is *** using the Lagrangian method,a kinetic model of the vectored electric propulsion system is established and validated through ground *** fake gyroscopic torque is first proposed,which the vector mechanism should overcome besides the inertial torque and the gravitational *** fake gyroscopic torque is caused by the difference between inertial moments about two principal inertial axes of the propeller in the rotating plane,appears only when the propeller is rotating and is proportional with the rotation *** is a sinusoidal pulse,with a frequency that is twice of the rotation *** the fake gyroscope torque pulse and aerodynamic efficiency,three blade propeller is recommended for the vectored propulsion system used for stratosphere airship.

关键词： stratosphere airship vectored electric propulsion system kinetic model vector torque fake gyroscopic torque blade number

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邵氏无痛手法联合中药塌渍、牵引治疗神经根型颈椎病49例疗效观察

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中国民族民间医药 2024年第13期33卷 92-95页

作者：王旭伟崔改琴程斌郑州市颈肩腰腿痛医院腰腿痛科河南郑州450000

目的:观察邵氏无痛手法联合中药塌渍、牵引对神经根型颈椎病患者的临床疗效。方法:选取98例神经根型颈椎病患者,随机数字表法分为对照组(n=49)、观察组(n=49)。对照组给予中药塌渍配合牵引治疗,观察组在对照组基础上给予邵氏无痛手法治... 详细信息

目的:观察邵氏无痛手法联合中药塌渍、牵引对神经根型颈椎病患者的临床疗效。方法:选取98例神经根型颈椎病患者,随机数字表法分为对照组(n=49)、观察组(n=49)。对照组给予中药塌渍配合牵引治疗,观察组在对照组基础上给予邵氏无痛手法治疗。比较两组颈椎活动度、颈椎等长肌力、疼痛和压痛视觉模拟评分量表(VAS)、颈部功能障碍指数(NDI)、血清前列腺素E 2(PGE 2)、P物质(SP)、临床疗效。结果:治疗后观察组颈椎活动度(前屈、后伸、左旋、右旋)、颈椎等长肌力(前屈、后伸、左侧屈、右侧屈)高于对照组(P<0.05);治疗后观察组疼痛和压痛VAS评分、NDI评分低于对照组(P<0.05);治疗后观察组PGE 2、SP低于对照组(P<0.05);观察组总有效率(91.84%)高于对照组(75.51%)(P<0.05)。结论:邵氏无痛手法联合中药塌渍、牵引治疗CSR患者疗效确切,可改善颈椎功能、减轻疼痛程度。

关键词：神经根型颈椎病邵氏无痛手法中药塌渍牵引功能活动疼痛程度

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Identification and characterization of genes involved in the jasmonate biosynthetic and signaling pathways in mulberry(Morus notabilis)

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Journal of Integrative Plant Biology 2014年第7期56卷 663-672页

作者： Qing wang Bi Ma Xiwu Qi Qing Guo xuwei wang Qiwei Zeng Ningjia He State Key Laboratory of Silkworm Genome Biology Southwest University

Jasmonate （JA） is an important phytohormone regulating growth, development, and environmental response in plants, particularly defense response against herbivorous insects. Recently, completion of the draft genome of the mulberry （Morus notabilis） in conjunction with genome sequencing of silkworm （Bombyx mori） provides an opportuni-ty to study this unique plant-herbivore interaction. Here, we identified genes involved in JA biosynthetic and signaling pathways in the genome of mulberry for the first time, with the majority of samples showing a tissue-biased expression pattern. The analysis of the representative genes 12-oxophy-todienoic acid reductase （OPRs） and jasmonate ZIM-domain （JAZs） was performed and the results indicated that the mulberry genome contains a relatively smal number of JA biosynthetic and signaling pathway genes. A gene encoding an＆amp;nbsp;important repressor, MnNINJA, was identified as an alternative splicing variant lacking an ethylene-responsive element binding factor-associated amphiphilic repression motif. Having this fundamental information wil facilitate future functional study of JA-related genes pertaining to mulberry-silkworm interactions.

关键词： Jasmonate mulberry (Morus notabilis) pathway silkwormCitation: wang Q, Ma B, Qi x, Guo Q, wang x, zeng Q, He N (2014)Identification and characterization of genes involved in the jasmonatebiosynthetic and signaling pathways in mulberry (Morus notabilis). J

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Drought weakens the positive effect of plant diversity on community biomass

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Journal of Plant Ecology 2024年第4期17卷 141-153页

作者： Yanhui Hou Xiaona Li Yanxia Hu xuwei Lu Yue Ma Wenmin Li Xiran Lü Zimo Li Yaxuan Bai Chao wang Institute of Grassland Flowers and EcologyBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China College of Grassland Science Shanxi Agricultural UniversityJinzhong 030801China College of Landscape Architecture and Art Henan Agricultural UniversityZhengzhou 450002China College of Agriculture and Forestry Hebei North UniversityZhangjiakou 075000China

Drought can greatly impact the biodiversity of an ecosystem and play a crucial role in regulating its ***,the specific mechanisms by which drought mediate the biodiversity effect(BE)on community biomass in above-and belowground through functional traits remain poorly ***,we conducted a common garden experiment in a greenhouse,which included two plant species richness levels and two water addition levels,to analyze the effects of biodiversity on aboveground biomass(AGB),belowground biomass(BGB)and total biomass(TB),and to quantify the relationship between BEs and functional traits under drought *** analysis focused on partitioning BEs into above-and belowground complementarity effect(CE)and selection effect(SE)at the species level,which allowed us to better understand the impacts of biodiversity on community biomass and the underlying *** results showed that plant species richness stimulated AGB,BGB and TB through *** decreased AGB,BGB and TB,*** addition,the aboveground CE was positively associated with the variation in plant *** in above-and belowground were negatively correlated with the community mean plant height and root length,***,drought weakened the aboveground CE by decreasing variation in plant height,resulting in a reduction in AGB and *** findings demonstrate that the complementarity of species is an important regulator of community biomass in above-and belowground,the dynamics of biomass under environmental stress are associated with the response of sensitive compartments.

关键词： biodiversity effect drought plant height root length aboveground biomass belowground biomass

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Pickering emulsion transport in skeletal muscle tissue:A dissipative particle dynamics simulation approach

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Chinese Journal of Chemical Engineering 2024年第4期68卷 65-75页

作者： xuwei Liu Wei Chen Yufei Xia Guanghui Ma Reiji Noda Wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Division of Environmental Engineering Science Graduate School of Science and TechnologyGunma University1-5-1 Tenjin-choKiryuGunma 376-8515Japan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Lymph node targeting is a commonly used strategy for particulate vaccines,particularly for Pickering ***,extensive research on the internal delivery mechanisms of these emulsions,especially the complex intercellular interactions of deformable Pickering emulsions,has been surprisingly *** gap in knowledge holds significant potential for enhancing vaccine *** study aims to address this by summarizing the process of lymph-node-targeting transport and introducing a dissipative particle dynamics simulation method to evaluate the dynamic processes within cell *** transport of Pickering emulsions in skeletal muscle tissue is specifically investigated as a case *** factors impacting the transport process are explored,including local cellular tissue environmental factors and the properties of the Pickering emulsion *** simulation results primarily demonstrate that an increase in radial repulsive interaction between emulsion particles can decrease the transport ***,larger intercellular gaps also diminish the transport efficiency of emulsion droplet particles due to the increased motion complexity within the intricate transport space compared to a single *** study sheds light on the nuanced interplay between engineered and biological systems influencing the transport dynamics of Pickering *** insights hold valuable potential for optimizing transport processes in practical biomedical applications such as drug ***,the desired transport efficiency varies depending on the specific *** instance,while a more rapid transport might be crucial for lymph-node-targeted drug delivery,certain applications requiring a slower release of active components could benefit from the reduced transport efficiency observed with increased particle repulsion or larger intercellular gaps.

关键词： Pickering emulsion Skeletal muscular cells Transport phenomena Dissipative particle dynamics Drug delivery

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Effects of Atmospheric Pressure on Developmental Characteristics and the Stability of Air Entraining Agent for Concrete

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 979-989页

作者：李立辉牛开民 TIAN Bo CHEN Xin FU Ziqian ZHU xuwei School of Civil Engineering Chongqing Jiaotong UniversityChongqing 400074China Transportation Science and Engineering Harbin Institute of TechnologyHarbin 150090China Research Institute of Highway Ministry of TransportBeijing 100088China

In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA(air-entraining agent)solution bubbles,AEA solution experiments and AEA solution bubble experiments were,respectively,conducted in Peking(50 m,101.2 kPa)and Lhasa(3,650 m,63.1 kPa).Surface tensions and inflection-point concentrations were tested based on AEA solutions,whilst developmental characteristics,thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA *** study involved three types of AEAs,which were TM-O,226A,and *** experimental results show that initial sizes of TM-O,226A,and 226S are,respectively,increased by 43.5%,17.5%,and 3.8%.With the decrease of ambient pressure,the drainage rate and the drainage index of AEA solution bubbles *** experiments show that the liquid film thicknesses of all tested AEA solution bubbles are in micron *** the atmospheric pressure decreases from 101.2 to 63.1 kPa,the liquid film thicknesses of three types of AEA solutions decrease in various degrees;and film elasticities at critical thicknesses *** film of 226S solution bubbles is the most stable,presenting as a minimum thickness *** should be noted that elastic coefficient of liquid film only represents the level at critical thickness,thus it can not be applied as the only evaluating indicator of bubble *** a type of AEA,factors affecting the stability of its bubbles under low atmospheric pressure include initial bubbles size,liquid film thickness,liquid film elasticity,ambient temperature,etc.

关键词： air-entraining agent surface tension bubble size liquid film thickness liquid film elasticity atmospheric pressure

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Astronomical forcing and sedimentary noise modeling of lake-level changes in the Middle Eocene Chezhen Sag,Bohai Bay Basin,eastern China

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Frontiers of Earth Science 2024年第2期18卷 446-459页

作者： xuwei LUAN Jinliang ZHANG Na LI Tao CHEN Long SUN Xuecai ZHANG Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Management Center of Oil and Gas Exploration Sinopec Shengli OilfieldDongying 257000China

The accurate determination of geological age is a key to understanding the history and process of paleolake evolution and oil and gas exploration in continental lake ***,improving the accuracy of geological age has always been a difficult scientific problem.A 609-m-thick,continuous lacustrine mudstone and sandstone succession in Chezhen Sag(eastern China)provides an ideal middle Eocene sedimentary record for establishing a high-resolution stratigraphic chronology *** on spectrum analysis and sliding window spectrum analysis of the natural gamma(GR)logging data of well Che 271(C271)in Chezhen Sag,the periods of 405 kyr and 40.1 kyr were filtered by a Gaussian bandpass filter,and a“floating”astrochronological time scale(ATS)was *** total number of 405 kyr eccentricity cycles were 13.6 and 40.1 kyr obliquity cycles were 138 which recorded from the upper member 4(Es4U)to the member 3(Es3)of the Eocene Shahejie Formation,and the depositional duration was 5.53 *** Coefficient(COCO)analysis and evolutionary Correlation Coefficient(eCoCo)analysis found that the optimal sedimentary rate of different *** noise simulation revealed the history of paleolake water changes in the Middle Eocene in the Chezhen Sag,according to which four sequences are *** study shows that the lake level change of Chezhen Sag in the middle Eocene shows prominent 1.2 Myr cycles and an antiphase well-coupled relationship with obliquity ***,we propose a model to explain the relationship between the orbital cycle and lake level change in the continental lake *** the obliquity of the earth increases,the middle and high latitudes of the earth will be closer to the sun,the direct sunlight will be higher,and the meridional sunshine will increase,thus accelerating the evaporation process of lake basin *** the seasonal changes are obvious(maximum period of 1.2 Myr ultra-long obliquity),this effect is more signific

关键词： Chezhen Sag cyclostratigraphy astrochronological time scale sedimentary noise

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