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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 role.Based 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 stability.Our 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 lowest.Seed morphological traits and underlying surface could generally explain the TWS.During 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 dispersal.Buried 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 distance.The results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed farther.Shape index and wind speed were the two significant influencing factors on the burial of seeds.The 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 long-distance dispersal are more complex.In summar

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

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New Rural Community Construction or Retention Development:A Comparative Analysis of Rural Settlement Transition Mechanism in Plain Agriculture Area of China Based on Actor Network Theory

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Chinese Geographical Science 2024年第3期34卷 436-452页

作者： qu Yanbo DONG Xiaozhen MA Wenqiu zhao Weiying School of Public Administration and Policy Shandong University of Finance and EconomicsJinan 250014China Institute of Land Science and Policy Shandong University of Finance and EconomicsJinan 250014China College of Engineering China Agricultural UniversityBeijing 100083China

It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization.

关键词： rural settlement transition(RST) actor network theory(ANT) transition path transition mechanism plain area China

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Development of small molecule drugs targeting immune checkpoints

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Cancer Biology & Medicine 2024年第5期21卷 382-399页

作者： Luoyi Chen Xinchen zhao Xiaowei Liu Yujie Ouyang chuan Xu Ying Shi Department of Oncology Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital School of MedicineUniversity of Electronic Science and Technology of China Institute for Breast Health Medicine State Key Laboratory of Biotherapy West China Hospital Sichuan University Acupuncture and Massage College Chengdu University of Traditional Chinese Medicine

Immune checkpoint inhibitors(ICIs) are used to relieve and refuel anti-tumor immunity by blocking the interaction, transcription, and translation of co-inhibitory immune checkpoints or degrading co-inhibitory immune checkpoints. Thousands of small molecule drugs or biological materials, especially antibody-based ICIs, are actively being studied and antibodies are currently widely used. Limitations, such as anti-tumor efficacy, poor membrane permeability, and unneglected tolerance issues of antibody-based ICIs, remain evident but are thought to be overcome by small molecule drugs. Recent structural studies have broadened the scope of candidate immune checkpoint molecules, as well as innovative chemical inhibitors. By way of comparison, small molecule drug-based ICIs represent superior oral bioavailability and favorable pharmacokinetic features. Several ongoing clinical trials are exploring the synergetic effect of ICIs and other therapeutic strategies based on multiple ICI functions, including immune regulation, anti-angiogenesis, and cell cycle regulation. In this review we summarized the current progression of small molecule ICIs and the mechanism underlying immune checkpoint proteins, which will lay the foundation for further exploration.

关键词： CD47 Immune checkpoints programmed death protein 1 signal-regulatory protein α small molecule drugs

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Trophic niche and adaptation in highland lizards:sex has greater influences than species matching

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Integrative Zoology 2024年第3期19卷 564-576页

作者： Shengnan YANG Jiapeng qu Ke TANG Xinquan zhao Huakun ZHOU Junhua HU Chengdu Institute of Biology Chinese Academy of SciencesChengduChina Qinghai Provincial Key Laboratory of Restoration Ecology for Cold Region Northwest lnstitute of Plateau BiologyChinese Academy of SciencesXiningChina University of Chinese Academy of Sciences BeijingChina Qinghai University XiningChina

The plateau environments are typically arid,cool,and high altitude,posing formidable challenges to wildlife survival due to resource scarcity and harsh conditions.Unraveling ecological adaptability in severe conditions requires a deeper understanding of the niche characteristics of plateau species.Trophic niche,which is a comprehensive indicator describing the energy acquisition strategy of animals,remains relatively understudied in plateau species.Here,by combining stable isotopes and morphological data,we quantified the trophic niches of two allopatric lizard species(Phrynocephalus vlangalii and P.erythrurus)that live in the hinterland of the Qinghai–Tibetan Plateau,and explored how their trophic niches correlate with morphological and environmental factors.While both trophic niche and morphological traits were similar between species,noteworthy distinctions were observed between male and female Phrynocephalus lizards.The morphological traits associated with predation(i.***.limb length and head size)and reproduction(i.***.abdomen length),annual mean temperature,and sex played influential roles in shifting trophic niches.These results imply that sexual dimorphism may facilitate inter-sex divergence in resource utilization,leading to trophic niche variations in the highland lizards.Furthermore,extreme environmental stress can constrain interspecific divergence in morphological and trophic traits.Our findings illustrate the dynamic variations of trophic niches in highland lizards,contributing to a more comprehensive understanding of the adaptation strategies employed by lizard species in plateau environments.

关键词： environmental adaptation Phrynocephalus Qinghai-Tibetan Plateau sexual dimorphism stable isotope

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Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action

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China Ocean Engineering 2024年第1期38卷 54-67页

作者： WANG Pi-guang LYU Si-yu qu Yang zhao Mi DU Xiu-li State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Tech-nologyBeijing 100124China

This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water depth.The governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible assumptions.The governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary conditions.The analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite water.The main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion ratios.The added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering applications.The calculation results show that the simplified formulas are in good agreement with the analytical solutions.

关键词： earthquake hydrodynamic pressure truncated cylinder added mass simplified formula

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Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： zhao Mi YU Wan-li WANG Pi-guang qu Yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic performance.In this study,a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD)approach,in which the unsteady,noncompressible Reynolds Averaged Navier‒Stokes(RANS)method is used.The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions.Subsequently,the finite element model is established by considering fluid/structure interactions to study the structural stress,displacement,strain distributions and flow field information of the structure under the uniform wind speed.Finally,the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect.The variation rules of the dynamic response of the one-way and twoway fluid−structure interaction(FSI)models under different wind speeds are analyzed,and the numerical calculation results are compared with those of the centralized mass model.The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine,which in turn affects the aerodynamic performance and structural stability of the blades.The structural dynamic response of the coupled model shows significant similarity,while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model.The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the twoway FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

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Lymphatic vessel:origin,heterogeneity,biological functions,and therapeutic targets

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Signal Transduction and Targeted Therapy 2024年第2期9卷 442-478页

作者： zhaoliang Hu Xushi zhao Zhonghua Wu Bicheng qu Minxian Yuan Yanan Xing Yongxi Song Zhenning Wang Department of Surgical Oncology and General Surgery The First Hospital of China Medical UniversityKey Laboratory of Precision Diagnosis and Treatment of Gastrointestinal Tumors(China Medical University)Ministry of Education155 North Nanjing StreetHeping DistrictShenyang 110001China

Lymphatic vessels,comprising the secondary circulatory system in human body,play a multifaceted role in maintaining homeostasis among various tissues and organs.They are tasked with a serious of responsibilities,including the regulation of lymph absorption and transport,the orchestration of immune surveillance and responses.Lymphatic vessel development undergoes a series of sophisticated regulatory signaling pathways governing heterogeneous-origin cell populations stepwise to assemble into the highly specialized lymphatic vessel networks.Lymphangiogenesis,as defined by new lymphatic vessels sprouting from preexisting lymphatic vessels/embryonic veins,is the main developmental mechanism underlying the formation and expansion of lymphatic vessel networks in an embryo.However,abnormal lymphangiogenesis could be observed in many pathological conditions and has a close relationship with the development and progression of various diseases.Mechanistic studies have revealed a set of lymphangiogenic factors and cascades that may serve as the potential targets for regulating abnormal lymphangiogenesis,to further modulate the progression of diseases.Actually,an increasing number of clinical trials have demonstrated the promising interventions and showed the feasibility of currently available treatments for future clinical translation.Targeting lymphangiogenic promoters or inhibitors not only directly regulates abnormal lymphangiogenesis,but improves the efficacy of diverse treatments.In conclusion,we present a comprehensive overview of lymphatic vessel development and physiological functions,and describe the critical involvement of abnormal lymphangiogenesis in multiple diseases.Moreover,we summarize the targeting therapeutic values of abnormal lymphangiogenesis,providing novel perspectives for treatment strategy of multiple human diseases.

关键词： therapeutic origin specialized

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Environmentally persistent free radicals in PM_(2.5)from a typical Chinese industrial city during COVID-19 lockdown:The unexpected contamination level variation

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Journal of Environmental Sciences 2024年第1期135卷 424-432页

作者： Lingyun Wang Wuduo zhao Peiru Luo Qingyun He Wenfen Zhang chuan Dong Yanhao Zhang College of Chemistry Zhengzhou UniversityZhengzhou 450001China Center of Advanced Analysis and Gene Sequencing Key Laboratory of Molecular Sensing and Harmful Substances Detection TechnologyZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China Institute of Environmental Science Shanxi UniversityTaiyuan 030006China

The outbreak of COVID-19 has caused concerns globally.To reduce the rapid transmission of the virus,strict city lockdown measures were conducted in different regions.China is the country that takes the earliest home-based quarantine for people.Although normal industrial and social activities were suspended,the spread of virus was efficiently controlled.Simultaneously,another merit of the city lockdown measure was noticed,which is the improvement of the air quality.Contamination levels of multiple atmospheric pollutants were decreased.However,in this work,24 and 14 air fine particulate matter(PM_(2.5))samples were continuously collected before and during COVID-19 city lockdown in Linfen(a typical heavy industrial city in China),and intriguingly,the unreduced concentration was found for environmentally persistent free radicals(EPFRs)in PM_(2.5)after normal life suspension.The primary non-stopped coal combustion source and secondary Cu-related atmospheric reaction may have impacts on this phenomenon.The cigarette-based assessment model also indicated possible exposure risks of PM_(2.5)-bound EPFRs during lockdown of Linfen.This study revealed not all the contaminants in the atmosphere had an apparent concentration decrease during city lockdown,suggesting the pollutants with complicated sources and formation mechanisms,like EPFRs in PM_(2.5),still should not be ignored.

关键词： PM_(2.5) EPFRs COVID-19 City lockdown Health risks

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An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-Ping Qiao Qing-Qing Li Wei-Guang He Dan zhao qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic imaging.In recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous media.However,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous media.In this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal equation.The novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat principle.Combined with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp contrasts.Several numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

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Emerging strategies for nerve repair and regeneration in ischemic stroke:neural stem cell therapy

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Neural Regeneration Research 2024年第11期19卷 2430-2443页

作者： Siji Wang Qianyan He Yang qu Wenjing Yin Ruoyu zhao Xuyutian Wang Yi Yang Zhen-Ni Guo Stroke Center Department of Neurologythe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of Neurologythe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Breast Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchunJilin ProvinceChina

Ischemic stroke is a major cause of mortality and disability worldwide,with limited treatment options available in clinical practice.The emergence of stem cell therapy has provided new hope to the field of stroke treatment via the restoration of brain neuron function.Exogenous neural stem cells are beneficial not only in cell replacement but also through the bystander effect.Neural stem cells regulate multiple physiological responses,including nerve repair,endogenous regeneration,immune function,and blood-brain barrier permeability,through the secretion of bioactive substances,including extracellular vesicles/exosomes.However,due to the complex microenvironment of ischemic cerebrovascular events and the low survival rate of neural stem cells following transplantation,limitations in the treatment effect remain unresolved.In this paper,we provide a detailed summary of the potential mechanisms of neural stem cell therapy for the treatment of ischemic stroke,review current neural stem cell therapeutic strategies and clinical trial results,and summarize the latest advancements in neural stem cell engineering to improve the survival rate of neural stem cells.We hope that this review could help provide insight into the therapeutic potential of neural stem cells and guide future scientific endeavors on neural stem cells.

关键词： bystander effect cell replacement extracellular vesicles ischemic stroke neural stem cells neural stem cell engineering

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