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Typical atmospheric haze during crop harvest season in northeastern China：A case in the Changchun region

Journal of Environmental Sciences 2017年第4期29卷 101-113页

作者： Wei Wei Chen Daniel Q.Tong Mo Dan Shi Chun zhang xue lei zhang Yue Peng Pan Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China . Cooperative Institute for Climate & Satellites University of Maryland College Park MD 20740 USA Center for Spatial Information Science and Systems George Mason University Fairfax VA 22030 USA Beijing Municipal Institute of Labor Protection Beijing 100054 China State key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

This study presents the mass concentrations of PM（2.5）,O3,SO2 and NOxat one urban,one suburban and two rural locations in the Changchun region from September 25 to October 272013. Major chemical components of PM（2.5）at the four sites were daily sampled and analyzed. Most of daily concentrations of SO2（7–82 μg/m^3）,O3（27–171 μg/m^3） and NOx（14–213 μg/m^3） were below the limits of the National Ambient Air Quality Standard（NAAQS）in China. However,PM（2.5）concentrations（143–168 μg/m^3） were 2-fold higher than *** PM（2.5）concentrations（~ 150 μg/m^3） were measured during the pre-harvest and harvest at the urban site,while PM（2.5）concentrations significantly increased from 250 to400 μg m^（-3） at suburban and rural sites with widespread biomass burning. At all sites,PM（2.5）components were dominated by organic carbon（OC） and followed by soluble component sulfate（SO4^（2-））,ammonium（NH4~＋） and nitrate（NO3^-）. Compared with rural sites,urban site had a higher mineral contribution and lower potassium（K~＋and K） contribution to PM（2.5）.Severe atmospheric haze events that occurred from October 21 to 23 were attributed to strong source emissions（e.g.,biomass burning） and unfavorable air diffusion ***,coal burning originating from winter heating supply beginning on October 18 increased the atmospheric pollutant emissions. For entire crop harvest period,the Positive Matrix Factorization（PMF） analysis indicated five important emission contributors in the Changchun region,as follows： secondary aerosol（39%）,biomass burning（20%）,supply heating（18%）,soil/road dust（14%） and traffic（9%）.

关键词： Aerosol Air quality Agriculture Biomass burning PM(2.5) PMF

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A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang xue zhang Jingjing Meng Qinghua lei Department of Earth Sciences ETH ZürichZürich8092Switzerland Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK Department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden Department of Earth Sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

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Effects of wind speed,underlying surface,and seed morphological traits on the secondary seed dispersal in the Tengger Desert,China

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Journal of Arid Land 2024年第4期16卷 531-549页

作者： QU Wenjie ZHAO Wenzhi YANG Xinguo WANG lei zhang xue QU Jianjun Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education Ningxia UniversityYinchuan 750021China University of Chinese Academy of Sciences Beijing 100049China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key *** on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its *** results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the *** morphological traits and underlying surface could generally explain the *** the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed *** seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long *** results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed *** index and wind speed were the two significant influencing factors on the burial of *** explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and lo

关键词： seed dispersal seed morphological traits wind speed vegetation regeneration wind tunnel Tengger Desert

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Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： xue-Qing Wang Cheng Song Ting lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

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Multilevel Micro Structures of the Clam Make the Sealing Even Tighter

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Journal of Bionic Engineering 2024年第3期21卷 1442-1452页

作者： Daobing Chen Xiaolong zhang Junqiu zhang Zhiwu Han Ruteng Wang Zhen Lin Yifeng lei Longjian xue Sheng Liu The Institute of Technological Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China

Excellent fluid sealing performance is crucial to ensuring the safety of important equipment,especially in aerospace field,such as space capsule and fuel *** frequently opening and closing of the sealing devices is particularly *** by this background,clams(Mactra chinensis)which can open and close their double shells with superior sealing performance,are studied in this ***,we show that the clam’s sealing ability is the result of its unique multilevel intermeshing microstructures,including hinge teeth and *** microstructures,which resemble gear teeth,engage with each other when the shell closes,forming a tight structure that prevents the infiltration of water from the ***,the presence of micron blocks prevents the penetration of finer *** simulation results of the bionic end seal components show that the multilevel microstructure has a superior sealing *** research is expected to be applied to undersea vehicles that require frequent door opening and closing.

关键词： Multilevel micro structures Opening and closing components Clam Sealing Bionic

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Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

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World Journal of Psychiatry 2024年第9期14卷 1319-1325页

作者： Gui-Bo Wang xue-Feng zhang Bing Liang Jie lei Jun xue Department of Pediatric Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Department of General Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective *** surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment *** To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic *** A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were *** observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the *** White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(Pleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

关键词： Pediatric abdominal infection Nucleic acid detection of broad-spectrum bacterial infection Bacterial culture Drug sensitivity testing Treatment effect Cost Mental health

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Light-driven sextuple theranostics:nanomedicine involving second near-infrared AIE-active Ir(Ⅲ)complex for prominent cancer treatment

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Science China Chemistry 2024年第7期67卷 2314-2324页

作者： xue Liu Jiangao Li Fei zhang Dingyuan Yan lei Wang Dong Wang Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Material Science and EngineeringShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Shenzhen 518172China

Light-driven cancer theranostics has shown inexhaustible and vigorous vitality by virtue of its high efficacy,prominent controllability and *** of an all-round theranostic material simultaneously affording both multimodal diagnosis imaging and synergistic phototherapy would be an appealing yet significantly challenging ***,a novel nanomedicine Ir@PPEG-MeEPO was ingeniously constructed by integrating beforehand1O2-charged amphiphilic polymer and well-tailored Ir(Ⅲ)complex IrDPTP,which was featured by second near-infrared(NIR-Ⅱ)aggregation-induced emission(AIE)tendency,efficient reactive oxygen species(ROS)generation,good photothermal conversion efficiency and high-performance hydrogen gas *** the best of our knowledge,IrDPTP held the longest emission wavelength among all reported AIE Ir(Ⅲ)***,Ir@PPEG-MeEPO was capable of controllably releasing ROS via triggered photothermal effect upon NIR irradiation,making it well-adapted to hypoxic environment of *** distinctive characteristics of Ir@PPEG-MeEPO endowed it with unprecedented performance on sextuple theranostics comprised of NIR-Ⅱfluorescence-photoacoustic-photothermal trimodal imaging and photodynamic-photothermal-hydrogen trimodal therapy,witnessed by the precise tumor diagnosis and complete tumor *** study would open up new perspectives for the exploration of superior nanomedicine for practical cancer theranostics.

关键词： aggregation-induced emission NIR-II emission cancer theranostics multimodal diagnosis imaging multimodal therapy

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Spatial transmission and meteorological determinants of tuberculosis incidence in Qinghai Province,China:a spatial clustering panel analysis

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Infectious Diseases of Poverty 2016年第1期5卷 376-388页

作者： Hua-Xiang Rao Xi zhang lei Zhao Juan Yu Wen Ren xue-lei zhang Yong-Cheng Ma Yan Shi Bin-Zhong Ma Xiang Wang Zhen Wei Hua-Fang Wang Li-Xia Qiu Department of Health Statistics School of Public HealthShanxi Medical UniversityNo.56 Xinjian South RoadTaiyuanShanxi 030001China Department of Epidemiology Richard M.Fairbanks School of Public HealthIndiana UniversityIndianapolisIN 46202USA Department of Biochemistry and Molecular Biology School of Basic Medical SciencesShanxi Medical UniversityTaiyuanShanxi 030001China Institute for Communicable Disease Control and Prevention Qinghai Center for Disease Control and PreventionXiningQinghai 810007China

Background:Tuberculosis(TB)is the notifiable infectious disease with the second highest incidence in the Qinghai province,a province with poor primary health care *** the spatial distribution of TB and related environmental factors is necessary for developing effective strategies to control and further eliminate ***:Our TB incidence data and meteorological data were extracted from the China Information System of Disease Control and Prevention and statistical yearbooks,*** calculated the global and local Moran’s I by using spatial autocorrelation analysis to detect the spatial clustering of TB incidence each year.A spatial panel data model was applied to examine the associations of meteorological factors with TB incidence after adjustment of spatial individual effects and spatial ***:The Local Moran’s I method detected 11 counties with a significantly high-high spatial clustering(average annual incidence:294/100000)and 17 counties with a significantly low-low spatial clustering(average annual incidence:68/100000)of TB annual incidence within the examined five-year period;the global Moran’s I values ranged from 0.40 to 0.58(all P-values<0.05).The TB incidence was positively associated with the temperature,precipitation,and wind speed(all P-values<0.05),which were confirmed by the spatial panel data *** 10°C,2 cm,and 1 m/s increase in temperature,precipitation,and wind speed associated with 9%and 3%decrements and a 7%increment in the TB incidence,***:High TB incidence areas were mainly concentrated in south-western Qinghai,while low TB incidence areas clustered in eastern and north-western *** with low temperature and precipitation and with strong wind speeds tended to have higher TB incidences.

关键词： Tuberculosis incidence Meteorological factors Spatial clustering Spatial panel data model

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Combination losartan with hyaluronic acid modified diethyldithiocarbamate loaded hollow copper sulfide nanoparticles for the treatment of breast cancer and metastasis

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Chinese Chemical Letters 2024年第3期35卷 406-414页

作者： Haili Hu Weiwei zhang lei lei Fan Tong Huilin zhang Yiwei zhang Wenqin Yang Yilu Tang Ruyi Lin xue Xia Jiamei Li Shiyong Song Huile Gao Key Laboratory of Drug Targeting and Drug Delivery Systems West China School of PharmacySichuan UniversityChengdu 610041China School of Pharmacy Henan UniversityKaifeng 475004China Department of Public Health Chengdu Medical CollegeChengdu 610500China

The application of photothermal therapy(PTT)is greatly limited by the low accumulation of photothermal agents,uneven photothermal distribution,and heat endurance of cancer *** still,despite PTT enhances immunogenicity,the anti-tumor immune efficacy is still unsatisfactory due to the inefficient immunogenic cell death(ICD)induction and poor infiltration of immune *** solve the above problems of PTT,we developed hyaluronic acid(HA)modified hollow copper sulfide nanoparticles encapsulating diethyldithiocarbamate(DDTC)to construct a breast tumor targeting and near infrared(NIR)photo-responsive drug delivery system(D-HCuS@HA),which further combined with losartan to improve the accumulation and penetration in the tumor *** irradiation,D-HCuS@HA realized enhanced PTT and released cytotoxic Cu(DDTC)_(2)to eliminate heat endurance tumor cells,thereby enhancing antitumor effect and inducing effective ***,the combination with losartan could remodel the tumor microenvironment,allowing more T cells to infiltrate into the tumor,and significantly inhibiting the occurrence and development of metastatic *** vitro/vivo results revealed the great potential of D-HCuS@HA combined with losartan,which provides a new paradigm for anti-tumor and anti-metastases.

关键词： Targeted drug delivery system Hollow copper sulfide nanoparticles Photothermal therapy Hyaluronic acid Breast cancer Anti-metastasis

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Weakly supervised point cloud segmentation via deep morphological semantic information embedding

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 695-708页

作者： Wenhao xue Yang Yang lei Li Zhongling Huang Xinggang Wang Junwei Han Dingwen zhang School of Automation Northwestern Polytechnical UniversityXi'anChina Institute of Mechanical and Electrical Engineering BeijingChina School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhanChina

Segmenting the semantic regions of point clouds is a crucial step for intelligent agents to understand 3D *** supervised point cloud segmentation is highly desirable because entirely labelling point clouds is highly time-consuming and *** the low-costing labelling of 3D point clouds,the scene-level label is one of the most effortless label ***,due to the limitation of classifier discriminative capability and the orderless and structurless nature of the point cloud data,existing scene-level method is hard to transfer the semantic information,which usually leads to the under-activated or over-activated *** this end,a local semantic embedding network is introduced to learn local structural patterns and semantic ***,the proposed network contains graph convolution-based dilation and erosion embedding modules to implement‘inside-out’and‘outside-in’semantic information dissemination ***,the proposed weakly supervised learning framework could achieve the mutual propagation of semantic information in the foreground and *** experiments on the widely used ScanNet benchmark demonstrate the superior capacity of the proposed approach when compared to the current alternatives and baseline models.

关键词： artificial intelligence computer vision deep learning

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