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Stable carbon isotope composition and intrinsic water use efficiency in plants along an altitudinal gradient on the eastern slope of Yulong Snow Mountain, china

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Ecological Processes 2024年第2期13卷 218-230页

作者： Feng Jiang Tao Pu Zi-Jing Xue Yan-Wei Ma xiao-Yi Shi Fu-xi Shi College of Geography and Environmental Sciences Zhejiang Normal University Yulong Snow Mountain Glacier and Environment Observation and research Station/State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of Forestry Jiangxi Agricultural University

Background Stable carbon isotope composition(δ13Cp) can be used to estimate the changes in intrinsic water use efficiency（iWUE） in plants,which helps us to better understand plants' response strategies to climate *** study focused on the variations in δ13Cpand iWUE for the different life-form plants（i.e.,herbs,shrubs,and trees）along an altitudinal gradient（3300,3600,3900,4100,4300,and 4500 m） on the eastern slope of Yulong Snow Mountain,southeastern margin of the Qinghai-Tibet *** response mechanisms of δ13Cpand iWUE for different life-form plants to altitude were thoroughly analyzed in this mountain *** The δ13Cpvalues of plants on the eastern slopes of Yulong Snow Mountain ranged from-30.4‰to-2..55‰,with a mean of-2..02.,indicating a dominance of *** δ13Cpand iWUE values varied among different life-form plants in the order of herbs> shrubs> trees,particularly in 3600,3900,and 4300 ***δ13Cpand iWUE values for herbs and shrubs increased with altitude and were mainly controlled by air *** two parameters for trees exhibited a trend of initial decrease followed by an increase with *** 3900 m,the δ13Cpand iWUE values decreased with altitude,influenced by soil ***,above 3900 m,the two parameters increased with altitude,mainly regulated by air *** addition,iWUE was positively correlated with leaf P content but negatively correlated with leaf N:P ratio,especially for herbs and trees,suggesting that P plays a key role in modulating iWUE in this *** The diffe rentiated responses of water availability for different life-form plants to a higher altitudinal gradient are regulated by air temperature,soil moisture,and leaf P content in the Yulong Snow *** results provide valuable insights into understanding the wate r-carbon relationships in high-altitude ecosystems.

关键词： Stable carbon isotope Water use efficiency Altitude Life form Yulong Snow Mountain

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Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： Yong Hu xi Lu Hai-Bo Wang Ji-Chao Fang Yi-Ning Wu Jian Fang Sun SINOPEC Petroleum Exploration and Production research institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-2. wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 2. wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

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A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： Jian Li Yu-xi Ji xiao-xiao Ni Kai-He Lv xian-Bin Huang Jin-Sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid research institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2.acrylamido-2.methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12.m L)after aging at high temperatures(up to2.0℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

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research on feed-pulse collaborative control method in micro-electrical discharge machining

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Advances in Manufacturing 2024年第2期12卷 270-287页

作者： Qiang Gao Ya-Ou Zhang Xue-Cheng xi Yuan-Ding Wang xiao-Fei Chen Wan-Sheng Zhao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China State Key Laboratory of Mechanical System and Vibration Shanghai200240People’s Republic of China Shanghai institute of Space Propulsion Shanghai201112People’s Republic of China

Reducing the short-circuit rate and increasing the effective discharge rate are important targets for improving the servo control effect of micro-electrical discharge machining(micro-EDM),as these two indicators are closely related to the machining efficiency and *** this study,a feed-pulse collaborative control(FPCC)method is proposed for micro-EDM based on two dimensions(space and time).In the spatial dimension,a feed control strategy with a discharge holding process is ***,in the time dimension,a forward-looking pulse control strategy is adopted,in which the pulse interval is adjusted based on a sequence analysis of feed commands and discharge *** experiments are carried out to determine the key parameters used in this method,including the discharge holding threshold and pulse interval adjustment value(T_(off_(adj))).The feed smoothness and discharge sufficiency analyses of the experimental results show that compared to the traditional double threshold average voltage method,the FPCC method reduces the number of long-distance retreats by 64%and improves the effective discharge time by 40%.

关键词： Micro-electrical discharge machining(micro-EDM) Electrode feed control Discharge pulse control Machining surface quality

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Technical alternatives for coke oven gas utilization in china: A comparative analysis of environment-economic-strategic perspectives

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Environmental Science and Ecotechnology 2024年第5期21卷 168-177页

作者： Zichen Di Feixia Lei Jiankai Jing Hao Peng xi Lu Fangqin Cheng institute of Resources and Environmental Engineering Shanxi UniversityTaiyuan030006PR China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing100084PR China institute for Carbon Neutrality Tsinghua UniversityBeijing100084PR China

china is the largest coke producer and *** is a pressing need to address the high emissions of air pollutants and carbon dioxide associated with traditional coking *** the nation pursues a transition towards carbon neutrality,expanding supply chains for coking plants to produce hydrogen,methanol,and other green alternatives has garnered significant ***,the relative advantages of these strategies have remained *** this study,we integrate a life cycle assessmenteconomic analysis-scenario analysis model to evaluate various coke oven gas(COG)utilization routes(COGtM:COG-to-methanol,COGtLNG:COG-to-liquefied natural gas,COGtSA:COG-to-synthetic ammonia,and COGtH:COG-to-hydrogen).The results indicate that COGtSA emerges as the preferred option for balancing environmental and economic ***,COGtM demonstrates economic viability but is associated with higher environmental *** being recognized as a significant strategic direction under carbon neutrality initiatives,COGtH faces economic feasibility and risk resilience *** encounters both financial and environmental challenges,necessitating strategic development from an energy security *** projected coking capacity is anticipated to experience a slight increase in the mid-term yet a significant decline in the long term,influenced by steel production *** potential future markets,COGtM is estimated to potentially capture a maximum market share of 16e34%in the methanol ***,against the backdrop of continuously expanding potential demand for hydrogen,COGtH holds advantages as a transitional solution,but in the long run,it can only meet a small portion of the *** can meet 7e14%of market demand and emerges as the most viable pathway from the viewpoint of balancing environmental and economic aspects and covering future markets.

关键词： Coke oven gas Life cycle assessment Economic analysis Comprehensive benefits Transformation strategy

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High-Order DG Schemes with Subcell Limiting Strategies for Simulations of Shocks,Vortices and Sound Waves in Materials Science Problems

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2183-2204页

作者： Zhenhua Jiang xi Deng xin Zhang Chao Yan Feng xiao Jian Yu College of Aeronautics Science and Engineering Beijing University of Aeronautics and AstronauticsBeijing100191China Department of Chemical Engineering Imperial College LondonLondonSW72AZUK Department of Engineering University of CambridgeCambridgeCB21PZUK Department of Mechanical Engineering Tokyo Institute of TechnologyTokyo152-8550Japan

Shock waves,characterized by abrupt changes in pressure,temperature,and density,play a significant role in various materials science processes involving *** high-energy phenomena are utilized across multiple fields and applications to achieve unique material properties and facilitate advanced manufacturing *** simulations of these phenomena require numerical schemes that can represent shock waves without spurious oscillations and simultaneously capture acoustic waves for a wide range of wavelength *** work suggests a high-order discontinuous Galerkin(DG)method with a finite volume(FV)subcell limiting strategies to achieve better subcell resolution and lower numerical diffusion *** switching to the FV discretization on an embedded sub-cell grid,the method displays advantages with respect to both DG accuracy and FV shock-capturing *** FV scheme utilizes a class of high-fidelity schemes that are built upon the boundary variation diminishing(BVD)reconstruction *** method is therefore able to resolve discontinuities and multi-scale structures on the subcell level,while preserving the favorable properties of the high-order DG *** have tested the present DG method up to the 6th-order accuracy for both smooth and discontinuous noise problems.

关键词： Discontinuous Galerkin finite volume subcell limiting shock associated noise computational aeroacoustics

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A Hybrid Approach for Predicting the Remaining Useful Life of Bearings Based on the RReliefF Algorithm and Extreme Learning Machine

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1405-1427页

作者： Sen-Hui Wang xi Kang Cheng Wang Tian-Bing Ma xiang He Ke Yang School of Mechatronics Engineering Anhui University of Science and TechnologyHuainan232001China institute of Energy Hefei Comprehensive National Science CenterHefei230031China

Accurately predicting the remaining useful life(RUL)of bearings in mining rotating equipment is vital for mining *** research aims to distinguish the features associated with the RUL of bearings and propose a prediction model based on these selected *** study proposes a hybrid predictive model to assess the RUL of rolling element *** proposed model begins with the pre-processing of bearing vibration signals to reconstruct sixty time-domain *** hybrid model selects relevant features from the sixty time-domain features of the vibration signal by adopting the RReliefF feature selection ***,the extreme learning machine(ELM)approach is applied to develop a predictive model of RUL based on the optimal *** model is trained by optimizing its parameters via the grid search *** training datasets are adjusted to make them most suitable for the regression model using the cross-validation *** proposed hybrid model is analyzed and validated using the vibration data taken from the public XJTU-SY rolling element-bearing *** comparison is constructed with other traditional *** experimental test results demonstrated that the proposed approach can predict the RUL of bearings with a reliable degree of accuracy.

关键词： Bearing degradation remaining useful life estimation RReliefF feature selection extreme learning machine

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Treadmill exercise improves hippocampal neural plasticity and relieves cognitive deficits in a mouse model of epilepsy

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Neural Regeneration research 2024年第3期19卷 657-662页

作者： Hang Yu Mingting Shao xi Luo Chaoqin Pang Kwok-Fai So Jiandong Yu Li Zhang Key Laboratory of CNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina State Key Laboratory of Brain and Cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Neuroscience and Neurorehabilitation institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina Department of Neurosurgery The First Affiliated Hospital of Bengbu Medical CollegeBengbuShandong ProvinceChina School of Psychology Shanghai University of SportShanghaiChina

Epilepsy frequently leads to cognitive dysfunction and approaches to treatment remain *** regular exercise effectively improves learning and memory functions across multiple neurological diseases,its application in patients with epilepsy remains ***,we adopted a 14-day treadmill-exercise paradigm in a pilocarpine injection-induced mouse model of *** assays confirmed the improvement of object and spatial memory after endurance training,and electrophysiological studies revealed the maintenance of hippocampal plasticity as a result of physical *** of the mechanisms underlying this effect revealed that exercise protected parvalbumin interneurons,probably via the suppression of neuroinflammation and improved integrity of blood-brain *** summary,this work identified a previously unknown mechanism through which exercise improves cognitive rehabilitation in epilepsy.

关键词： blood-brain barrier cognition hippocampus interneurons long-term potentiation microglial cell neuroinflammation spatial memory temporal epilepsy treadmill exercise

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Long noncoding RNAs HAND2.AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2.axis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1547-1563页

作者： Qiang Zou Hao-Wen Wang xi-Liang Di Yuan Li Hui Gao Department of Interventional Therapy Tianjin Medical University Cancer Institute and HospitalTianjin 300060China National Clinical research Center for Cancer Key Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030Heilongjiang ProvinceChina Department of Hematology and Oncology Linyi People’s HospitalLinyi 251500Shandong ProvinceChina Department of Comprehensive Oncology Baotou Cancer HospitalBaotou 014030Inner Mongolia Autonomous RegionChina

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2.AS1 was downregulated in HCC tissues,but its role in HCC progression is *** targeted microbubble destruction mediated gene transfection is a new method to overexpress *** To study the role of ultrasound microbubbles(UTMBs)mediated HAND2.AS1 in the progression of HCC,in order to provide a new reference for the treatment of *** In vitro,we transfected HAND2.AS1 siRNA into HepG2.cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,*** addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell ***,the UTMBs treated HepG2.cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2.TIMP2.overexpression vector,and we detected cell proliferation,apoptosis,invasion and *** vivo,we established a mouse model of subcutaneous transplantation of HepG2.cells and observed the effect of HAND2.AS1 silencing on tumor formation *** We found that UTMBs carrying HAND2.AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2.AS1 silencing eliminated the effect of ***,miR-873-5p targets the gene HAND2.AS1,which also targets the 3’UTR of *** miR-873-5p mimic counteracted the impact of ***,miR-873-5p mimic solely or in combination with pcDNA-TIMP2.had been transformed into HepG2.cells exposed to *** discovered that TIMP2.reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2.*** vivo results showed that HAND2.AS1 silencing sig

关键词： Hepatocellular carcinoma Ultrasound microbubbles Long noncoding RNA HAND2.AS1 miR-873-5p Tissue inhibitor of matrix metalloproteinase-2

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Identification of TMEM2.7 as a novel prognostic biomarker and potential therapeutic target in acute myeloid leukemia

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Genes & Diseases 2024年第4期11卷 90-93页

作者： Yunying Yao Zhizhou xi Min Wu Bo Jiao Jiaming Gao Donghe Li xi xie Pengfei Xu Jiaoyang Li Lei Yan Ruibao Ren Ping Liu Shanghai institute of Hematology State Key Laboratory for Medical GenomicsNational Research Center for Translational MedicineCollaborative Innovation Center of HematologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghai 200025China International Center for Aging and Cancer Hainan Medical UniversityHaikouHainan 570102China

Despite remarkable advances in molecular and cell biology of acute myeloid leukemia(AML),AML patients still frequently relapse and have low 5-year overall survival(OS)rates.1 It is worth noting that a recent study from the registry or clinical trial compilation has reported an improvement in the OS of adult AML patients,especially those under 60 years of age.

关键词： acute myeloid leukemia

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