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Science China(life Sciences) 2022年第1期65卷 151-166页

作者： Yue Wang Yunfei Zheng weiran li Department of Orthodontics Peking University School and Hospital of StomatologyBeijing 100081China

Osteoclastogenesis in alveolar bone induced by compression stress triggers orthodontic tooth *** stress also stimulates angiogenesis,which is essential for ***,the effects of osteoclastogenesis induced by compression on angiogenesis are poorly *** vivo,we found the markers of angiogenesis increased during orthodontic bone *** vitro,osteoclast-derived exosomes increased proliferation,migration,and tube formation of human umbilical vein endothelial cells(HUVECs),as well as expression of vascular endothelial growth factor and *** promotive effects of exosomes derived from compressed osteoclasts were greater than those derived from osteoclasts without ***,we analyzed changes in the micro RNA transcriptome after compression stress and focused on micro RNA146 a-5 p(mi R-146 a),which was significantly decreased by *** of an inhibitor of mi R-146 a stimulated angiogenesis of HUVECs while mi R-146 a mimics repressed ***(ADP)was confirmed to be a target of mi R-146 a by dual luciferase reporter *** HUVECs treated with exosomes,we detected increased ADP which promoted *** of ADP in HUVECs reduced the promotive effects of *** results demonstrate that the decreased mi R-146 a observed in osteoclasts after compression promotes angiogenesis by targeting ADP,suggesting a novel method to interfere with bone remodeling induced by compression stress.

关键词： micro RNA-146a-5p adiponectin angiogenesis compression stress osteoclastogenesis exosomes

Tectonic Evolution of the North Depression of the South Yellow Sea Basin Since Late Cretaceous

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Journal of Ocean University of China 2016年第6期15卷 967-976页

作者： li Nan li weiran LONG Haiyan College of Marine Geoscience Ocean University of China

Abstract On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow Sea basin are quantitatively studied. The results show that the tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous can be divided into a rifting phase （late Cretaceous to Paleogene） and a post-rifting phase （Neogene to Quaternary）. The rifting phase can be further subdivided into an initial rifting stage （late Cretaceous）, an intensive rifting stage （Paleocene）, a rifting termination stage （Eocene）, and an inversion-uplifting stage （Oligocene）. Together, this division shows the characteristics of an episodic-evolved intracontinental rift-depression basin. The deformation of the north depression of the south Yellow Sea basin since late Cretaceous was mainly fault-related. The horizontal extension and tectonic subsidence were controlled by the activity of faults. The differential evolution of faults also caused variations in local uplift/subsidence movements and the regional heterogeneity in extension. The late Cretaceous initial rifting of the north depression of the south Yellow Sea basin is related to the Pacific-Eurasia convergence. From the Paleocene intensive rifting stage to present, the Pacific-Eurasia convergence and India-Eurasia convergence have played important roles in the evolution of this region.

关键词： subsidence history balanced cross-section tectonic evolution South Yellow Sea Basin

Exosomes derived from osteoclasts under compression stress inhibit osteoblast differentiation

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BIOCELL 2021年第2期45卷 427-444页

作者： YUE WANG YUNFEI ZHENG weiran li Department of Orthodontics Peking University School and Hospital of StomatologyBeijing10081China

Orthodontic tooth movement is triggered by orthodontic force loading on the periodontal ligament and is achieved by alveolar bone remodeling,which is regulated by intimate crosstalk between osteoclastogenesis and osteoblast *** the communication between osteoclasts and osteoblasts is influenced by orthodontic compression stress requires further *** this study,osteoclasts were differentiated for 10 *** day 4 of differentiation,the number of pre-osteoclasts peaked,as determined by the increased expression of RANK and the number of multinucleated *** 24 h of compression stress loading,on day 4,the number of osteoclasts increased,and the optimal magnitude of stress to promote osteoclastogenesis was determined as 1 g/***,the results of RNA-sequencing analysis showed that the miRNA expression profile changed markedly after compression loading and that many of the altered miRNAs were associated with cell communication functions.A series of indirect co-culture experiments showed an inhibitory effect of osteoclasts on osteoblast differentiation,especially after ***,we added osteoclast-derived exosomes to hPDLSCs during osteoblast *** derived from osteoclasts under compression(cEXO)showed a greater inhibitory effect on osteoblast differentiation,compared to exosomes from osteoclasts without compression(EXO).Therefore,we analyzed differentially expressed miRNAs associated with bone development functions in exosomes:miR-223-5p and miR-181a-5p were downregulated,whereas miR-133a-3p,miR-203a-3p,miR-106a-5p,and miR-331-3p were upregulated;these altered expressions may explain the enhanced inhibitory effect of compression stress.

关键词： Osteoclastogenesis Osteogenesis Compression stress Exosome microRNA

Chronological link Between the Abrupt Change of the Loess Grain Size Sequence and the Formation of River Terraces on the Eastern Margin of the Qinghai-Tibetan Plateau Since the Late Early-Pleistocene

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 723-732页

作者： liU Dongyan QIAO Yansong li weiran XIE Ruihuang PENG Shasha College of Marine Geoscience Ocean University of China Qingdao 266100 China Key Laboratory of Submarine Science and Prospecting Techniques Ministry of Education Qingdao 266100 China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China College of Physical andEnvironmental Oceanography Ocean University of China Qingdao 266100 China Department of Meteorology University of Hawaii at Manoa Honolulu 96822 USA

Based on the study of magnetostratigraphy,magnetic susceptibility and grain size of Garze A section on the southeastern margin of the Qinghai-Tibetan Plateau since the late early-Pleistocene,the basal age of Garze loess is located at～1.16 MaBP and a series of abrupt paleoclimatic changes is *** times of abrupt changes are of distinct series features,and the interval between each two adjacent abrupt changes is～50 kyr or～100 *** most significant abrupt changes occur at around 1.06,0.85,0.6,0.46,0.39 and 0.14 *** is a chronological link between the abrupt changes of paleoclimate and the formation of river terraces and it is almost simultaneous with a strengthening trend of neotectonic ***,maybe the climatic transition controll the timing of terrace formation,and the tectonic uplift originate potential energy and has a direct effect on channel incision, both the climatic transition and the tectonic uplift are *** are the products of the interaction of instable climatic variations and tectonic *** the loess-paleosol sequences,river terrace sequences are also controlled by the climate-tectonic coupling system and are ruled by climate-tectonic gyration with a～100 kyr paracycle,which may be the short eccentricity period of the earth.

关键词： Garze loess grain size terrace tectonic uplift the Qinghai-Tibetan Plateau

Kinetic study of the gas-phase reaction of O3 with three unsaturated alcohols

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Journal of Environmental Sciences 2018年第9期30卷 292-299页

作者： weiran li Yi Chen Shengrui Tong Yucong Guo Yunhong Zhang Maofa Ge The Institute of Chemical Physics School of Chemistry and Chemical Engineering Beijing Institute of Technology Beijing 100081 China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of SciencesBeijing 100190 China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Peking University Beijing 100871 China University of Chinese Academy of Sciences Beijing 100049 China CAS Research/Education Center for Excellence in Molecular Sciences Beijing 100190 China

Rate constants for the reactions of ozone with 1-octen-3-ol, 1-nonen-3-ol and 1-nonen-4-ol have been determined at 298 ±1 K and atmospheric pressure for the first time. The experiments were performed in a 100-L FEP Teflon film bag using absolute rate method; the rate constants were （1.91 ± 0.19） ×10^-17, （1.89 ± 0.20） × 10^-17, and （0.83 ± 0.08） × 10^-17 cm^3/（***） for 1-octen-3-ol, 1-nonen-3-ol, and 1-nonen-4-ol, respectively. The rate constants have been compared with those of unsaturated alcohols structural homologs, and used to estimate the reaction reactivity. The electronegativity of carbon-carbon double bond was calculated by atomic charges analysis. The calculated results show that the electronic effect of the lone pair electrons of hydroxyl oxygen is the main cause of the difference in rate coefficient. According to the obtained rate constants, the atmospheric lifetimes of studied unsaturated alcohols were also estimated, which indicates that the reaction with ozone is an important loss pathway in the atmosphere, especially in polluted areas.

关键词： Rate constant Ozone Unsaturated alcohols Atmospheric lifetime

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International Journal of Oral Science 2024年第3期16卷 398-412页

作者： Yunfan Zhang Jiale Yan Yuning Zhang Hao liu Bing Han weiran li Department of Orthodontics Peking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Laboratory for Digital and Material Technology of Stomatology&Beijing Key Laboratory of Digital Stomatology&Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health&NMPA Key Laboratory for Dental MaterialsBeijingChina

Compared with teenage patients,adult patients generally show a slower rate of tooth movement and more pronounced alveolar bone loss during orthodontic treatment,indicating the maladaptation of alveolar bone homeostasis under orthodontic ***,this phenomenon is not well-elucidated to date,leading to increased treatment difficulties and unsatisfactory treatment outcomes in adult *** to provide a comprehensive knowledge and further inspire insightful understanding towards this issue,this review summarizes the current evidence and underlying *** age-related abatements in mechanosensing and mechanotransduction in adult cells and periodontal tissue may contribute to retarded and unbalanced bone metabolism,thus hindering alveolar bone reconstruction during orthodontic *** this end,periodontal surgery,physical and chemical cues are being developed to reactivate or rejuvenate the aging periodontium and restore the dynamic equilibrium of orthodontic-mediated alveolar bone *** anticipate that this review will present a general overview of the role that aging plays in orthodontic alveolar bone metabolism and shed new light on the prospective ways out of the impasse.

关键词： alveolar metabolism homeostasis

Reaction mechanism and kinetics of Criegee intermediate and hydroperoxymethyl formate

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Journal of Environmental Sciences 2021年第7期33卷 128-137页

作者： Meifang Chen Shengrui Tong Zhen Wang weiran li Yanyong Xu Sufan Wang Maofa Ge College of Chemistry and Material Science Anhui Normal UniversityWuhu 241000China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Chinese Academy of Sciences Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Center for Excellence in Regional Atmos.Environ. Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

The reaction mechanism and kinetics of the simplest Criegee intermediate CH_(2)OO reaction with hydroperoxymethyl formate(HPMF)was investigated at high-level quantum chemistry *** has two reactive functional groups,-C(O)OH *** calculated results of thermodynamic data and rate constants indicated that the insertion reactions of CH_(2) OO with-OOH group of HPMF were more favorable than the reactions of CH_(2)OO with-C(O)OH *** calculated overall rate constant was 2.33×10^(−13) cm^(3)/(moleculesec)at 298 K and the rate constants decreased as the temperature increased from 200 to 480 *** addition,we also proved the polymerization reaction mechanism between CH_(2)OO and-OOH of *** theoretical study interpreted the previous experimental results,and supplied the structures of the intermediate products that couldn’t be detected during the experiment.

关键词： Criegee intermediates Hydroperoxymethyl formate Mechanism Kinetics Polymerization

Kinetic and mechanism studies of the ozonolysis of three unsaturated ketones

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Journal of Environmental Sciences 2020年第9期32卷 23-32页

作者： weiran li Meifang Chen Yi Chen Shengrui Tong Maofa Ge Yucong Guo Yunhong Zhang State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Material Science The key Laboratory of Functional Molecular SolidsMinistry of EducationAnhui Laboratory of Molecule-Based MaterialsAnhui Normal UniversityWuhu 241000China CAS Research/Education Center for Excellence in Molecular Sciences Beijing 100190China Institute of Chemical Physics School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Reaction rate constants and products of 1-octen-3-one,3-octen-2-one and 4-hexen-3-one with ozone were studied in a 100-L fluorinated ethylene propylene(FEP) Teflon film bag using absolute rate method at 298 ± 1 K and atmospheric *** rate constants were(1.09 ± 0.12) × 10-17,(3.48 ± 0.36) × 10-17 and(5.70±0.60) × 10-17 cm3/(molecule·sec),*** to the obtained rate constants,the effects of carbonyl were *** carbonyl group in β position has a net withdrawing effect with respect to an olefinic bond,then causing the decline of rate *** quantum chemical calculation was used to explain the results of rate *** products of ozonolysis were mainly aldehydes,which have significant influence on the formation of SOA,and hence play an important role in the *** this work,we detected the main products of reaction and proposed the reaction mechanism by combining the results of quantum chemical *** lifetime for three unsaturated ketones reacted with ozone was 36.4,11.4 and 6.9 hr for 1-octen-3-one,3-octen-2-one and 4-hexen-3-one,respectively.

关键词： unsaturated ozone mechanism

Safety Analysis of Riding at Intersection Entrance Using Video Recognition Technology

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Computers, Materials & Continua 2022年第9期72卷 5135-5148页

作者： Xingjian Xue linjuan Ge Longxin Zeng weiran li Rui Song Neal N.Xiong College of Landscape Architecture Central South University of Forestry and TechnologyChangshaHunan410004China College of Logistics and Transportation Central South University of Forestry and TechnologyChangshaHunan410004China Department of Mathematics and Computer Science Northeastern State UniversityTahlequahOK74464United States

To study riding safety at intersection entrance,video recognition technology is used to build vehicle-bicycle conflict models based on the Bayesian *** is analyzed the relationship among the width of nonmotorized lanes at the entrance lane of the intersection,the vehicle-bicycle soft isolation form of the entrance lane of intersection,the traffic volume of right-turning motor vehicles and straight-going non-motor vehicles,the speed of right-turning motor vehicles,and straight-going non-motor vehicles,and the conflict between right-turning motor vehicles and straight-going nonmotor *** to the traditional statistical methods,to overcome the discreteness of vehicle-bicycle conflict data and the differences of influencing factors,the Bayesian random effect Poisson-log-normal model and random effect negative binomial regression model are *** results show that the random effect Poisson-log-normal model is better than the negative binomial distribution of random effects;The width of non-motorized lanes,the form of vehicle-bicycle soft isolation,the traffic volume of right-turning motor vehicles,and the coefficients of straight traffic volume obey a normal *** them,the type of vehicle-bicycle soft isolation facilities and the vehicle-bicycle traffic volumes are significantly positively correlated with the number of vehicle-bicycle *** width of non-motorized lanes is significantly negatively correlated with the number of vehicle-bicycle *** periods and flat periods,the average speed of right-turning motor vehicles,and the average speed of straight-going non-motor vehicles have no significant influence on the number of vehicle-bicycle conflicts.

关键词： Video recognition technology vehicle-bicycle conflict intersection entrance random effect poisson-log-normal model random effect negative binomial regression model

Atmospheric oxidizing capacity in autumn Beijing:Analysis of the O_(3) and PM_(2.5) episodes based on observation-based model

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Journal of Environmental Sciences 2023年第2期124卷 557-569页

作者： Chenhui Jia Shengrui Tong Xinran Zhang Fangjie li Wenqian Zhang weiran li ZhenWang Gen Zhang Guiqian Tang Zirui liu Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Chemistry Liaoning UniversityShenyang 110036China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry of CMA Institute of Atmospheric CompositionChinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Atmospheric oxidizing capacity(AOC)is the fundamental driving factors of chemistry process(e.g.,the formation of ozone(O_(3))and secondary organic aerosols(SOA))in the ***,accurate quantification of AOC still remains *** this study,a comprehensive field campaign was conducted during autumn 2019 in downtown of Beijing,where O_(3) and PM_(2.5) episodes had been experienced *** observation-based model(OBM)is used to quantify the AOC at O_(3) and PM_(2.5) *** strong intensity of AOC is found at O_(3) and PM2.5 episodes,and hydroxyl radical(OH)is the dominating daytime oxidant for both *** photolysis of O_(3) is main source of OH at O_(3) episode;the photolysis of nitrous acid(HONO)and formaldehyde(HCHO)plays important role in OH formation at PM_(2.5) *** radicals loss routines vary according to precursor pollutants,resulting in different types of air pollution.O_(3) budgets and sensitivity analysis indicates that O_(3) production is transition regime(both VOC and NOx-limited)at O3 *** heterogeneous reaction of hydroperoxy radicals(HO_(2))on aerosol surfaces has significant influence on OH and O_(3) production *** HO_(2) uptake coefficient(γHO_(2))is the determining factor and required accurate measurement in real atmospheric *** findings could provide the important bases for coordinated control of PM_(2.5) and O_(3) pollution.

关键词： Pollution episode Observation-based model Atmospheric oxidizing capacity Heterogeneous reaction Hydroxyl radical Budgets