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黄土丘陵区典型植被生态系统功能的权衡关系

草地学报 2024年第4期32卷 1234-1242页

作者：张飞郑诚袁浏欢林子琦姚宏斌温仲明西北农林科技大学草业与草原学院陕西杨陵712100 中国科学院教育部水土保持与生态环境研究中心陕西杨陵712100

为探究黄土高原植被恢复形成各群落生态系统功能权衡关系,本研究以植被恢复形成的灌木、自然草地、撂荒草地及乔木群落为对象,采用均方根偏差法(Root mean square deviation,RMSD)研究了生物量生产、土壤含水量、土壤养分含量、物种多样... 详细信息

为探究黄土高原植被恢复形成各群落生态系统功能权衡关系,本研究以植被恢复形成的灌木、自然草地、撂荒草地及乔木群落为对象,采用均方根偏差法(Root mean square deviation,RMSD)研究了生物量生产、土壤含水量、土壤养分含量、物种多样性4种生态系统功能差异及其权衡关系。结果表明:各植被类型间生态系统功能差异显著;各植被类型最高权衡均出现在生物量与其他生态系统功能间,RMSD在0.27~0.53间变化;乔木群落生态系统功能严重失衡,需要降低生物量促进各功能协调发展;灌木群落和自然草地群落生态系统功能中度失衡,是较为适合该区域的植被恢复的类型,两种群落分别需要改善土壤养分含量和土壤含水量;撂荒草地失衡程度最轻但生态系统功能低下,需要提升物种多样性及生物量。研究结果为黄土高原植被恢复调控与可持续发展提供依据。

关键词：黄土丘陵区植被恢复植被类型生态系统功能权衡关系

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AZGP1P2/UBA1/RBM15 Cascade Mediates the Fate Determinations of Prostate Cancer Stem Cells and Promotes Therapeutic Effect of Docetaxel in Castration-Resistant Prostate Cancer via TPM1 m6A Modification

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Research 2024年第3期6卷 151-167页

作者： hong Wang Jj Liu Xiaojun Zhu bin Yang Zuping He Xudong yao Department of Urology Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghaiChina Urologic Cancer Institute School of MedicineTongji UniversityShanghaiChina. Department of Urology Surgery The Affiliated Hospital of Inner Mongolia Medical UniversityHohhotChina. The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province School of MedicineHunan Normal UniversityThe Engineering Research Center of Reproduction and Translational Medicine of Hunan ProvinceChangshaChina Shanghai Key Laboratory of Reproductive Medicine Shanghai Jiao Tong University School of MedicineShanghaiChina.

Prostate cancer(PCa)is a common malignant tumor with high morbidity and mortality *** prostate cancer stem cell(PCSC)model provides novel insights into the pathogenesis of PCa and its therapeutic ***,the roles and molecular mechanisms of specific genes in mediating fate decisions of PCSCs and carcinogenesis of PCa remain to be *** this study,we have explored the expression,function,and mechanism of AZGP1P2,a pseudogene of AZGP1,in regulating the stemness and apoptosis of PCSCs and treatment resistance of docetaxel in castration-resistant prostate cancer(CRPC).We revealed that AZGP1P2 was downregulated in CRPC cell lines and PCSCs,while it was positively associated with progression-free *** of the AZGP1P2 enhanced the sensitivity of docetaxel treatment in CRPCs via inhibiting their *** pull-down associated with mass spectrometry analysis,co-immunoprecipitation assay,and RNA immunoprecipitation assay demonstrated that AZGP1P2 could bind to UBA1 and RBM15 as a“writer”of methyltransferase to form a ***1,an E1 ubiquitin-activating enzyme,contributed to RBM15 protein degradation via ubiquitination *** RNA immunoprecipitation assay displayed that RBM15 controlled the mRNA decay of TPM1 in m6A ***,a xenograft mouse model and patient-derived organoids showed that the therapeutic effect of docetaxel in CRPC was increased by AZGP1P2 in ***,these results imply that AZGP1P2 mediates the stemness and apoptosis of PCSCs and promotes docetaxel therapeutic effect by suppressing tumor growth and metastasis via UBA1/RBM15-mediated TPM1 mRNA decay in CRPC.

关键词： Prostate TPM1 m6A

Elevation of basal lacustrine sediments along the mid-lower reaches of the Yangtze River and its implications for the reconstruction of Holocene water levels

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Science China Earth Sciences 2024年第9期67卷 2924-2936页

作者： Shuchun yao Chunhai LI bin XUE Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The middle and lower reaches of the Yangtze River,a primary region for freshwater lakes in China,have undergone significant transformations throughout the *** changes,driven by factors such as sea-level rise,climate change,and human activities,have led to the progressive elevation of water levels in this *** a result,a floodplain has emerged,characterized by the formation of numerous shallow lakes along the river ***,the pattern of water-level changes in the main channel of the Yangtze River during the Holocene remains *** gap in knowledge poses challenges for understanding sediment transport dynamics,the interactions between the river and its adjacent lakes,and the prevention and control of flood disasters in the Yangtze River *** shed light on these issues,our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the Yangtze River ***,we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river’s main *** findings reveal that,particularly along the Jingjiang section,the basal elevation of most lakes is lower than the Yangtze River’s water level during the dry ***,the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang *** the tidal reach,especially within the Taihu Lake basin,the basal elevation of lakes typically falls below sea ***,lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the Yangtze River’s annual average and dry season water *** the widespread presence of lakes along the middle and lower reaches of the Yangtze River,our study introduces a new proxy for reconstructing the mean water level of the mid-lower Yangtze River in the *** analyzing sediments from Nanyi Lake and Chenyao Lake in the lower Yangtze River,we a

关键词： Middle and lower Yangtze River Holocene Water level Floodplain lakes Basal sediment elevation

Process-driven susceptibility assessment of glacial lake outburst debris flow in the Himalayas under climate change

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Advances in Climate Change Research 2024年第3期15卷 500-514页

作者： bin ZHOU Qiang ZOU Hu JIANG Tao YANG Wen-Tao ZHOU Si-Yu CHEN hong-Kun yao Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China

Global warming is causing glaciers to retreat and glacial lakes to expand in the Himalayas,which amplifies the risk of glacial lake outburst debris flows(GLODFs)and poses a significant threat to downstream lives and ***,the complex interplay between GLODF occurrences and associated indicators,coupled with the lack of a comprehensive susceptibility indicator system that considers the entire GLODF process,presents a substantial challenge in assessing GLODF susceptibility in the *** study proposes a process-driven GLODF susceptibility assessment indicator system responding to climate change that considers the complete process of GLODF formation,incorporating relevant parameters about upstream,themselves,and downstream of glacial ***,to mitigate subjective factors associated with traditional evaluation methods,we developed three novel hybrid machine-learning models by integrating classic machine-learning algorithms with the whale optimization algorithm(WOA)to delineate the distribution of GLODF susceptibility in the *** the hybrid models effectively predicted the GLODFs occurrence,with the WOA-SVC model demonstrating the highest prediction *** 34%of the catchments exhibit high and very high susceptibility levels,primarily concentrated along the north and south sides of the Himalayan ridge,particularly in the eastern and central *** capturing the physical formation process of hazards,such as topographic potential(highest relative importance value of 40%),can precisely identify GLODF.A total of 128 catchments pose potential transboundary threats,with 24 classified as having a very high susceptibility level and 25 as having a high susceptibility ***,the border region between China and Nepal is a prominent hotspot for transboundary threats of *** findings can provide valuable clues for disaster prevention,mitigation,and cross-border coordination in the Himalayas.

关键词： Glacial lake outburst debris flow Susceptibility assessment Climate change Himalayas

Restoring cosmological concordance with axion-like early dark energy and dark matter characterized by a constant equation of state?

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Communications in Theoretical Physics 2024年第7期76卷 74-82页

作者： Yan-hong yao Xin-He Meng School of Physics and Astronomy Sun Yatsen University 2 Daxue RoadTangjiaZhuhaiChina School of Physics Nankai University 94 Weijin RoadNankaiTianjinChina

The Hubble tension persists as a challenge in *** early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the S_(8)*** that a negative dark matter(DM)equation of state(EoS)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EDE model in this paper by replacing the cold dark matter(CDM)with DM characterized by a constant EoS w_(dm)(referred to as WDM hereafter).We then impose constraints on this axion-like EDE extension model,along with three other models:the axion-like EDE model,ΛWDM,and Λ*** constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on S_(8)(i.e.S_(8)=0.766±0.017,determined through the joint analysis of KID1000+BOSS+2dLenS).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the S_(8)tension to a level similar to that of the axion-like EDE model.

关键词： Hubble tension early dark energy noncold dark matter S8 tension

Observer-Based Adaptive Robust Precision Motion Control of a Multi-Joint Hydraulic Manipulator

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1213-1226页

作者： Zheng Chen Shizhao Zhou Chong Shen Litong Lyu Junhui Zhang bin yao State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027 Ocean College Zhejiang UniversityZhoushan 316021China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050000 State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907 USA

Hydraulic manipulators are usually applied in heavy-load and harsh operation ***,when faced with a complex operation,the traditional proportional-integral-derivative(PID)control may not meet requirements for high control ***-based full-state-feedback control is an effective alternative,but the states of a hydraulic manipulator are not always available and reliable in practical applications,particularly the joint angular velocity *** that it is not suitable to obtain the velocity signal directly from differentiating of position measurement,the low-pass filtering is commonly used,but it will definitely restrict the closed-loop bandwidth of the whole *** avoid this problem and realize better control performance,this paper proposes a novel observerbased adaptive robust controller(obARC)for a multi-joint hydraulic manipulator subjected to both parametric uncertainties and the lack of accurate velocity ***,a nonlinear adaptive observer is first designed to handle the lack of velocity measurement with the consideration of parametric ***,the adaptive robust control is developed to compensate for the dynamic uncertainties,and the close-loop system robust stability is theoretically proved under the observation and control ***,comparative experiments are carried out to show that the designed controller can achieve a performance improvement over the traditional methods,specifically yielding better control accuracy owing to the closed-loop bandwidth breakthrough,which is limited by low-pass filtering in fullstate-feedback control.

关键词： handle Observer filtering

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji Wang Ning Qi hong-yao Yin Yu-Jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

Metal-soil interface adhesion in clay clogging during shield tunneling:Theoretical model and experimental validation

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Underground Space 2024年第2期15卷 188-202页

作者： Yong Fang bin Zhuo Yubo Wang Hu Luo Junfeng Sun Yuxiang yao Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

Clogging is a major geohazards risk in mechanized tunnelling through cohesive *** clogging results from the high adhesion between the clay and *** on the water film theory and Reynolds fluid equation,the interfacial adhesion between metal and soil is simplified in this study as viscous hydrodynamic behavior between *** the influence of capillary force and the viscous force of water film at the interface between metal and soil,a theoretical calculation model of interfacial adhesion between metal and soil is *** influence of water film thickness and separation rate on the interfacial adhesion between metal and soil is qualitatively ***,the adhesion stress between the clay and the metal surface was tested with a pullout test and the influence of moisture content,pullout rates and types of clay minerals on the adhesion stress was ***,the calculation model of adhesion force was compared with the experimental *** calculation model of soil adhesion stress established in this paper can quantitatively describe the relationship between soil adhesion force and moisture content and can also qualitatively reveal the influence mechanism of soil moisture content on adhesion stress.

关键词： EPB clogging Adhesion stress Mechanics model Clays Mechanism analysis Experimental test

Soil conditioning of clay based on interface adhesion mechanism:Microscopic simulation and laboratory experiment

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Underground Space 2024年第5期18卷 239-255页

作者： Yong Fang bin Zhuo Ruyue Zhang Yubo Wang Liupan Dou Yuxiang yao Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

Clogging frequently occurs in the cutter head,excavation chamber or screw conveyor when an earth pressure balance(EPB)shield machine is tunneling in soft or silty clay ground with high clay mineral *** this paper,montmorillonite,kaolinite,and illite were selected as research objects,and molecular dynamics simulation and laboratory experiment were *** the microscopic scale,dynamic contact behavior and interfacial mechanical behavior of the interface between clay minerals and water/surfactant solution was simulated and the interfacial adhesion and conditioning mechanism between clay minerals and water/surfactant solution was ***,sodium dodecyl benzene sulfonate surfactant was selected as the main composition of the soil ***,the adhesion stress before and after soil conditioning and the contact angles between clay minerals and water/surfactant solution were tested and analyzed at the macroscopic *** result shows that the contact angle between droplet and clay mineral surface is an important parameter to characterize soil *** simulation rules of the microscopic contact angle are consistent with the experiment ***,the adsorption energy between microscopic substances is dominated by electrostatic force,which can reflect the adhesion stress between macroscopic *** adhesion stress can be effectively decreased by adding the surfactant to the soil conditioner.

关键词： EPB clogging Clay minerals Microscopic simulation Mechanism analysis Laboratory experiment Adhesion stress