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穿活动断裂带隧道抗错动易损性分析方法

岩土工程学报 2024年第10期46卷 2060-2068页

作者：禹海涛许桦霖卫一博同济大学土木工程防灾国家重点实验室上海200092 同济大学地下建筑与工程系上海200092

活动断层错动作用是导致穿断层隧道结构破坏的主要因素,因此评估穿断层隧道结构的抗错动性能对于隧道抗震设计至关重要,然而目前研究尚缺乏针对穿断裂带隧道结构抗错动性能的评估方法。为此,提出了一种面向穿活动断裂带隧道结构抗错动... 详细信息

活动断层错动作用是导致穿断层隧道结构破坏的主要因素,因此评估穿断层隧道结构的抗错动性能对于隧道抗震设计至关重要,然而目前研究尚缺乏针对穿断裂带隧道结构抗错动性能的评估方法。为此,提出了一种面向穿活动断裂带隧道结构抗错动性能评估的易损性分析方法。首先,基于概率断层位错危险分析(PFDHA)推导隧址区断层位错超越概率计算公式;其次,建立围岩-断层-隧道相互作用体系的有限元分析模型,并选定易损性分析指标,采用拟静力弹塑性分析方法得到隧道损伤与断层位错量之间的量化关系;最后采用隧址区断层位错超越概率计算公式计算出任意给定地震动水准条件下穿活动断裂带隧道结构的抗错动易损性。以某穿活动走滑断层隧道为例,依据所建立的易损性评估方法开展影响因素分析,探究了断层倾角对隧道结构抗错动性能的影响规律,结果表明:断层倾角越小,穿断层处隧道结构的易损性越小,且上盘侧隧道衬砌易损性显著高于下盘;隧道易损性对5~8级矩震级的变化更为敏感;隧道选线沿着近破裂带端部穿越可显著降低隧道结构的受损概率。该方法可以定量描述穿断层隧道在给定地震动强度下的易损性程度,可为穿活动断裂带隧道结构抗震设计与抗错动性能评估提供科学依据和分析手段。

关键词：穿断层隧道活动断裂带易损性地震响应 PFDHA

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A comparison of species composition and stand structure between planted and natural mangrove forests in Shenzhen Bay,South China

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Journal of Plant Ecology 2010年第3期3卷 165-174页

作者： Zhongkui Luo Osbert Jianxin Sun hualin xu MOE Key Laboratory for Silviculture and Conservation and Institute of Forestry and Climate Change Research Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Neilingding-Futian National Nature Reserve of Guangdong Shenzhen 518040China

Aims For assisting faster restoration of damaged or severely disturbed coastal ecosystems,selected mangrove species have been planted on previously mangrove-inhabited sites of the tropical and subtropical coasts of southern *** objective of this study was to understand the stand dynamics of the planted mangroves and their functional traits in comparison with natural mangrove forests under similar site *** Species composition,stand density,tree size distribution,and aboveground production were investigated along three transects in a 50-year-old planted mangrove stand and three transects in an adjacent natural mangrove stand in Shenzhen Bay,South *** were made on tree distribution by species,stand structure,and aboveground biomass(AGB)*** were performed on the spatial patterns of tree size distribution and species *** Findings We found that the planted and natural mangrove stands did not differ in stand density,average diameter at breast height(DBH),species composition,and *** distribution of AGB and frequency at species level were also similar between the planted and natural ***,the traits in stand structure were more variable in the planted stand than in the natural stand,indicating higher spatiotemporal heterogeneity in the development and succession of planted *** analyses show that both DBH and AGB were spatially auto-correlated within a specific range in the direction perpendicular to *** than 60%of the variance in these attributes was due to spatial *** Ripley’s K-function analysis shows that the two dominant species,Kandelia obovata and Avicennia marina,clumped in broader scales in the natural stand than in the planted stand and displayed significant interspecific competition across the whole *** is suggested that interspecific competition interacts with spatial autocorrelation as the underlying mechanism shaping th

关键词： coastal ecosystem forest restoration mangroves spatial autocorrelation species association

Temporal and vertical distribution of microphytobenthos biomass in mangrove sediments of Zhujiang (Pearl River) Estuary

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Acta Oceanologica Sinica 2013年第4期32卷 82-88页

作者： LIU Weiqiu ZHANG Jielong TIAN Guanghong xu hualin YAN Xiaohua School of Life Sciences Sun Yat-sen University Management Office of Qi'ao-Dangan Provincial Nature Reserve Guangdong Neilingding-Futian National Nature Reserve

Being a primary producer, Microphytobenthos （MPB） play an important role in the benthic ecosystem of mangrove swamps. The temporal and vertical distribution of MPB biomass, expressed as chlorophyll a （Chl a）, was investigated in mangrove swamps on the Qi＇ao island and the Futian Mangrove Nature Reserve, Guangdong Province, South China. Both locations are situated in the Zhujiang （Pearl River） Estuary. For each location, bi-monthly sampling was carried out at four sites during low tide period. Except one site on the Qi＇ao Island, which was in Phragrnites australis marsh, all sites were in mangrove swamps. The Chl a concentration in surface （0-1 cm） sediment ranged from 0.2/2g/cm3 to 8.3 #g/cm3 in the Qi＇ao Island and from 2.1/zg/cm3 to 15.6/2g/cm3 in the Futian Mangrove Reserve. The peak Chl a concentration occurred in winter or early spring, while the lowest Chl a concentration, with a value of about one quarter of the peak, was observed in summer or early autumn. The vertical distribution of Chl a concentration exhibited an exponential decline with depth, which indicated a muddy sediment with high organic matter, and the slope of the curve was positively related to Chl a concentration in the surface sediment. The MPB biomass of the Qi＇ao Island was significantly lower than that of the Futian Mangrove Reserve. Our results suggest that the overlaying water quality might influence the MPB biomass in surface sediments.

关键词： microphytobenthos mangrove biomass chlorophyll a vertical distribution

Seasonal Distribution of Meiofaunal Assemblages in the Mangrove Tidal Flat of Futian,Shenzhen,China

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Journal of Ocean University of China 2022年第4期21卷 955-964页

作者： SONG Yuanliu YAN Cunjun GAO Chunzi xu hualin HUA Er LIU Xiaoshou College of Marine Life Sciences Frontiers Science Center for Deep Ocean Multispheres and Earth SystemOcean University of ChinaQingdao 266003China Institute of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China Guangdong Neilingding-Futian National Reserve Administration Bureau Shenzhen 518040China

Meiofauna are fundamental components in mangrove ecosystem which play important roles in the energy flow and mat-ter *** order to reveal the spatio-temporal distribution of meiofaunal assemblages in mangrove habitats,sediment samples were collected in July(summer)and October(autumn)of 2013,January(winter)and April(spring)of 2014 in the mangrove tidal flat of Futian,Shenzhen,China.A total of 14 meiofaunal taxa were identified,including free-living marine nematodes,benthic copepods,polychaetes,oligochaetes,ostracods,isopods,***,there were also undetermined *** showed that the abun-dance range of meiofauna was(488.35±71.29)-(5136.36±623.38)ind(10 cm)−*** nematodes were the most dominant group,with an average abundance of(1869.56±227.92)ind(10 cm)−2,accounting for 98.35%of the total abundance of *** sea-sonal distribution of meiofauna showed that the abundance was the highest in summer,followed by those in spring,winter,and *** distribution showed that meiofauna were mainly distributed in the upper sediment layer(0-5 cm),with a proportion of 89.56%.Correlation analysis between meiofauna and environmental factors showed that meiofaunal abundance and biomass had significantly negative correlation with *** analysis between meiofaunal assemblages and environmental factors show-ed that meiofaunal assemblages were affected by the combined effects of temperature,salinity,sediment median grain size,water content,and chlorophyll a content.

关键词： meiofauna taxa composition abundance mangrove tidal flat seasonal distribution

In silico tests on sequence motif significances for human tissue specific genes

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Journal of Biomedical Science and Engineering 2013年第5期6卷 572-578页

作者： Xiujun Gong hualin xu School of Computer Science and Technology Tianjin University Tianjin China

Identification and analysis of tissue-specific (TS) genes and their regulatory activities play an important role in understanding the mechanisms of the organism, disease diagnosis and drug design. Although so far we are not clear about the mechanisms totally, the sequence features of TS genes are becoming an important clue. In this paper we used an integrated pipeline to discover sequences motifs for the promoter regions of TS genes. To test the significances of those motifs in a specific tissue, we used hypotheses test approaches including Bayesian hypothesis, Binomial distribution and traditional z-test. We finally got 2784, 1204 and 703 motifs respectively out of 3244 motifs obtained in discovery phase using above three tests from 3954 TS genes across 83 human tissues. 52.7% of those motifs can be found in public databases available.

关键词： Tissue Specific Genes Hypothesis Test Tissue Rich Motif Tissue Even Motif

A mixed-coordination electron trapping-enabled high-precision touch-sensitive screen for wearable devices

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Bio-Design and Manufacturing 2024年第4期7卷 413-427页

作者： Xi Zhang Junchi Ma hualin Deng Jinming Zhong Kaichen xu Qiang Wu Bo Wen Dongfeng Diao Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058China Shenzhen University General Hospital Shenzhen 518055China Research Center of Medical Plasma Technology Shenzhen UniversityShenzhen 518060China

Touch-sensitive screens are crucial components of wearable *** such as reduced graphene oxide(rGO),carbon nanotubes(CNTs),and graphene offer promising solutions for flexible touch-sensitive ***,when stacked with flexible substrates to form multilayered capacitive touching sensors,these materials often suffer from substrate delamination in response to deformation;this is due to the materials having different Young’s modulus *** results in failure to offer accurate touch screen *** this work,we demonstrate an induced charge-based mutual capacitive touching sensor capable of high-precision touch *** is enabled by electron trapping and polarization effects related to mixed-coordinated bonding between copper nanoparticles and vertically grown graphene ***,we used an electron cyclotron resonance system to directly fabricate graphene-metal nanofilms(GMNFs)using carbon and copper,which are firmly adhered to flexible *** being subjected to 3000 bending actions,we observed almost no change in touch *** screen interaction system,which has a signal-to-noise ratio of 41.16 dB and resolution of 650 dpi,was tested using a handwritten Chinese character recognition trial and achieved an accuracy of 94.82%.Taken together,these results show the promise of touch-sensitive screens that use directly fabricated GMNFs for wearable devices.

关键词： Flexible touch-sensitive screen Graphene-metal nanofilms Mixed coordination Wearable device

MicroRNA-126 deficiency affects the development of thymus CD4+SP cells through elevating IRS-1

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MicroRNA-126 deficiency affects the development of thymus CD...

The miR159a-DUO1 module regulates pollen development by modulating auxin biosynthesis and starch metabolism in citrus

第十二届全国免疫学学术大会

作者： chen chao xu hualin xu Lin Zunyi medical college

Recent evidence showed that microRNA-126(miR-126) was an important regulator in the development and function of immune cells including T ***,the potential role of miR-126 in the development of CD4T cells remains to be *** the present study,we firstly estimated the potential role of miR-126 deficiency on the development of CD4T cells in thymus using miR-126 knock down *** data showed that compared with those in control wild type(WT) mice,the volume and weight of thymus in miR-126 KD mice had no obvious ***,the total number of thymocytes in miR-126 KD mice increased ***,we found that the percentage and absolute number of thymic CD4SP cells in miR-126 KD mice decreased significantly at the age of 4 weeks and increased obviously at the age of 8 weeks,compared with these in WT *** analysis showed that the expression of activationassociated molecules including CD62 L,CD69 and CD44,as well as proliferation-associated nuclear antigen Ki-67,in CD4SP cells also significantly changed,*** aspect,we found that the expression of IRS-1,a putative target of miR-126,increased significantly in CD4SP ***,the expression of signaling molecules phosphor-Akt and phosphor-Erk also changed ***,our work firstly revealed a previous unknown role of miR-126 in the development of CD4SP cells in thymus,which might be ultimately benefit to the understanding of development of thymocytes.

关键词： miR-126 knock down thymus SP cells IRS-1

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Journal of Integrative Plant Biology 2024年第7期66卷 1351-1369页

作者： Yanhui xu Wenxiu Tian Minqiang Yin Zhenmei Cai Li Zhang Deyi Yuan hualin Yi Juxun Wu National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Cultivation and Protection for Non‐Wood Forest Trees of the Ministry of Education and Key Laboratory of Non‐Wood Forest Products of the Forestry Ministry Central South University of Forestry and TechnologyChangsha 410004China

Achieving seedlessness in citrus varieties is one of the important objectives of citrus *** sterility associated with abnormal pollen development is an important factor in ***,our understanding of the regulatory mechanism underlying the seedlessness phenotype in citrus is still ***,we determined that the miR159a-DUO1 module played an important role in regulating pollen development in citrus,which further indirectly modulated seed development and fruit *** the overexpression of csi-miR159a and the knocking out of DUO1 in Hong Kong kumquat(Fortunella hindsii)resulted in small and seedless fruit ***,pollen was severely aborted in both transgenic lines,with arrested pollen mitotic I and abnormal pollen starch *** additional cross-pollination experiments,DUO1 was proven to be the key target gene for miR159a to regulate male sterility in *** on DNA affinity purification sequencing(DAP-seq),RNA-seq,and verified interaction assays,YUC2/YUC6,SS4 and STP8 were identified as downstream target genes of DUO1,those were all positively regulated by *** transgenic *** lines,the miR159a-DUO1 module down-regulated the expression of YUC2/YUC6,which decreased indoleacetic acid(IAA)levels and modulated auxin signaling to repress pollen mitotic *** miR159a-DUO1 module reduced the expression of the starch synthesis gene SS4 and sugar transport gene STP8 to disrupt starch metabolism in ***,this work reveals a new mechanism by which the miR159a-DUO1 module regulates pollen development and elucidates the molecular regulatory network underlying male sterility in citrus.

关键词： auxin citrus male sterility miRNA pollen development seedlessness starch metabolism

Environmental remediation promotes the restoration of biodiversity in the Shenzhen Bay Estuary,South China

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Ecosystem Health and Sustainability 2022年第1期8卷 26-34页

作者： hualin xu Ke Liu Tianzhu Ning Gu Huang Qianmei Zhang Yuelin Li Mengqi Wang Yiming Fan Weili an Lingbo Ji Qinfeng Guo Hai Ren Neilingding-Futian National Nature Reserve Administration Bureau of Guangdong ShenzhenChina Department of Ecology South China Botanical GardenChinese Academy of SciencesGuangzhouChina University of Chinese Academy of Sciences BeijingChina CSCEC Aecom Consultans Co. Ltd Shenzhen BranchShenzhenChina Core Botanical Gardens Chinese Academy of SciencesGuangzhouChina School of Physics and Optoelectronic Engineering Foshan UniversityFoshanChina Zhongkai College of Agricultural Technology GuangzhouChina Eastern Forest Environmental Threat Assessment Center USDA Forest ServiceRTPNCUSA

Background:Rapid urbanization has greatly changed land-use patterns in many estuarine areas around the world,including the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)resulting in serious water pollution and ecosystem *** City has conducted comprehensive ecological management and restoration in the Shenzhen Bay since *** natural vegetation consisting of mangroves,semi-mangroves,wetland plants,and terrestrial plants were restored from the bund to the inner bank of the Fengtang *** and sewage flow diversion systems were *** non-point source and point-source sewage are now treated in municipal sewage treatment plants,then naturally flow through the constructed wetland,and then through a natural wetland,restored natural embankment,and finally through mangrove communities substantially improving water ***:The restoration of the wetland has increased animal and microbial diversity and has supported the establishment of a complex and stable food *** water purification and habitat restoration,the number of alien invasive plants in the estuarine ecosystem has decreased,and the diversity of native species of birds,fish,macrobenthos,amphibians,and reptiles has ***:These improvements indicate that human beings and nature can coexist in support of the sustainable development of Shenzhen City.

关键词： Coastal city sewage treatment ecological restoration mangrove bird diversity